A Quasi-Rapid Extinction Population Dynamics and Mammoths Overkill

a r X i v :p h y s i c s /0210031v 1 [p h y s i c s .c l a s s -p h ] 7 O c t 2002Notes on Quasi-Homogeneous Functions in ThermodynamicsF.Belgiorno ∗Dipartimento di Fisica,Universit`a degli Studi di Milano,Via Celoria 16,20133Milano,Italy(February 2,2008)A special kind of quasi-homogeneity occurring in thermodynamic potentials of standard thermo-dynamics is pointed out.Some formal consequences are also discussed.PACS:05.70.-aI.INTRODUCTIONQuasi-homogeneous functions have been introduced in the framework of standard thermodynamics with the aim to studying scaling and universality near the critical point [1,2].A common synonymous of “quasi-homogeneous function”is “generalized homogeneous function”[see e.g.[1,2,3]].We wish to point out here that quasi-homogeneity can be an useful tool in the framework of standard thermodynamics,when one considers intensive variables as independent variables for the equilibrium thermodynamics description of a system.In fact,homogeneity for the fundamental equation in the entropy representation [and in the energy representation]is well-defined in terms of the standard Euler theorem for homogeneous functions [4].One simply defines the standard Euler operator (sometimes called also Liouville operator)and requires the entropy [energy]to be an homogeneous function of degree one.When the other thermodynamic potentials which are obtained from the entropy [energy]are taken into account by means of suitable Legendre transformations,then part of the independent variables are intensive [4].The thermodynamic potentials are still homogeneous of degree one in the extensive independent variables,but a different rescaling is appropriate for the independent variables.For example,let us consider the Gibbs potential G (T,p,N )for a system which is described by means of three independent variables T,p,N .G is homogeneous of degree one when the system is rescaled by λ,such a rescaling corresponding only to a rescaling N →λN ,because T and p are intensive and remain unchanged under rescaling of the system.This is evident because,as it is well known,one has G =µ(p,T )N ,where µis the chemical potential.Actually,one could also define G as a quasi-homogeneous function of degree one with weights (0,0,1).Then the behavior under scaling is better defined.A mathematical treatment of the same problem is found in Ref.[5].The approach we present here is characterized by the more general setting allowed by the technology of quasi-homogeneous functions;the sections on the Gibbs-Duhem equation and the on Pfaffian forms contain a further analysis of some formal aspects of standard thermodynamics.II.QUASI-HOMOGENEOUS FUNCTIONS AND THERMODYNAMICSGiven a set of real coordinates x 1,...,x n and a set of weights α≡(α1,...,αn )∈I R n ,a function F (x 1,...,x n )is quasi-homogeneous of degree r and type α[6]if,under dilatations by a scale factor λ>0one findsF (λα1x 1,...,λα1x n )=λr F (x 1,...,x n ).(1)A differentiable quasi-homogeneous function satisfies a generalized Euler identity:D F =r F,(2)where D is the Euler vector fieldD ≡α1x 1∂∂x n.(3)Notice that(2)is a necessary and sufficient condition for a differentiable function to be quasi-homogeneous[6].It is also interesting to define quasi-homogeneous Pfaffain forms.A Pfaffian formω=ni=1ωi(x)dx i(4)is quasi-homogeneous of degree r∈I R if,under the scalingx1,...,x n→λα1x1,...,λαn x n(5) onefindsω→λrω.(6) This happens if and only if the degree of quasi-homogeneity deg(ωi(x))ofωi(x)is such that deg(ωi(x))=r−αi∀i= 1,...,n.For a discussion about quasi-homogeneity and for further references,see[7].A.quasi-homogeneous potentials in standard thermodynamicsLet us consider a thermodynamic potential R(y1,...,y k,x k+1,...,x n)depending on k intensive variables y1,...,y k and n−k extensive variables x k+1,...,x n.R is required to be quasi-homogeneous of degree1and its type isα=(0,...,0k,1,...,1 n−k).(7) Then,one hasR=n i=k+1x i∂R∂x n≡x n r(y1,...,y n−1),(9)where r(y1,...,y n−1)is of degree zero.We recall that,given the fundamental equation of thermodynamics in the energy[entropy]representation,one can obtain other fundamental equations by means of the Legendre transform[4].It is easy to show that:the Legendre transform with respect to a variable of weightαof a quasi-homogeneous function of degree r is a quasi-homogeneous function of degree r with the weightαchanged into the weight r−αof the Legendre-conjugate variable (theorem2of[1]).Moreover,the partial derivative with respect to a variable of weightαof a quasi-homogeneous function R of degree r is a quasi-homogeneous function of degree r−αhaving the same type as R(theorem1of[1]).See also[7].These results allow to justify easily the following examples.For the free energy F(T,V,N),one has F=U−T S,thus F is a quasi-homogeneous function of degree1and of weights(0,1,1),andF(T,V,N)=V ∂F∂N.(10)Analogously,S(T,V,N)=V ∂S∂N.(11)[In fact,S=−∂F/∂T and theorem1of[1]can be applied].Moreover,given S(T,p,N),one hasS(T,p,N)=N∂S∂x i ;R a≡∂R∂x i.(17) Let us also define a1-formωR≡ka=1R a dy a+n i=k+1R i dx i(18)where R a are quasi-homogeneous functions of degree one X R a=R a and the R i are quasi-homogeneous functions of degree zero X R i=0.ThenωR is a quasi-homogeneous1-form of degree one,in the sense that it satisfies L XωR=ωR, where L X is the Lie derivative associated with X.One can also define a functionR≡i XωR,(19) where i X is the standard contraction operator.As a consequence,onefindsdR=d(i XωR)=−i X dωR+L XωR=−i X dωR+ωR(20) IfωR is a closed1-form(and then,exact in the convex thermodynamic domain),then dωR=0and dR=ωR,i.e.R is the potential associated withωR.Notice also that in the latter case onefinds−i X dωR =0(21)which corresponds to the Gibbs-Duhem equation.In fact,one hasdωR =ka =1dR a ∧dy a+ni =k +1dR i ∧dx i(22)andi X dωR =k a =1(i X dR a )dy a−ka =1dR a (i X dy a )+ni =k +1(i X dR i )dx i−ni =k +1dR i (i X dx i )=k a =1R a dy a −ni =k +1x i dR i =0,(23)where i X dR a =X R a =R a ,and i X dR i =X R i =0.The converse is also true,i.e.,if (21)is satisfied then from (20)follows that ωR is closed.The GD equation is then satisfied because of the equality of the mixed second derivatives of R (Schwartz theorem)and because of the quasi-homogeneous symmetry.In fact,by defining Q αβthe matrix of the second partial derivatives of R ,one findsni =k +1x idR i =ka =1n i =k +1x i Q ia dy a+n j =k +1ni =k +1x i Q ij dx j .(24)Then the Gibbs-Duhem equation (16)is equivalent tok a =1ni =k +1x i Q ia dy a=ka =1R a dy a(25)n j =k +1ni =k +1x i Q ij dx j =0.(26)The former formula (25)is implemented if both Schwartz theorem and the quasi-homogeneous symmetry are imple-mented.In fact,ka =1n i =k +1x i Q ia dy a=ka =1n i =k +1xi∂∂y a Rdy a =ka =1∂∂x iRdy a=k a =1∂R∂x i∂∂x i∂RIV.PF AFFIAN FORMδQ revLet us consider the Pfaffian formδQ rev for a system described by(T,V,N),where T is the absolute temperature; one hasδQ rev=C V N(T)dT+a(T,V,N)dV+b(T,V,N)dN.(30)δQ rev has to be integrable,i.e.,it satisfiesδQ rev∧d(δQ rev)=0,and it is known that T is an integrating factor for δQ rev,withδQ revT =C V N(T)TdV+b(T,V,N)TV+b(T,V,N)∂x i,(A2) thenP(y1,...,y k,x k+1,...,x n)≡ni=k+1B i(y1,...,y k,x k+1,...,x n)x i(A3)is a potential associated with ω.In fact,let us considerdP =ni =k +1B i (y 1,...,y k ,x k +1,...,x n )dx i+ni =k +1x i dB i (y 1,...,y k ,x k +1,...,x n )(A4)=ni =k +1B i (y 1,...,y k,xk +1,...,x n)dx i+ni =k +1xinj =k +1∂B i∂y a(y 1,...,y k ,x k +1,...,x n )dy a .(A6)The exactness of the Pfaffian form ωimplies that dω=0and,in particular∂B i∂x ia =1,...,k ;i =k +1,...,n,(A7)∂B i∂x ii,j =k +1,...,n(A8)Then,one obtainsni =k +1x ik a =1∂B i ∂x i(y 1,...,y k ,x k +1,...,x n )dy a(A9)=ka =1ni =k +1x i∂∂xj (y 1,...,y k ,x k +1,...,x n )dx j =ni =k +1x inj =k +1∂B j∂x iB j (y 1,...,y k ,x k +1,...,x n )dx j (A13)=0,(A14)because each B i is quasi-homogeneous of degree zero.。

湖南省长郡中学2022-2023学年高二下学期第二次学情分析考试英语试题学校:___________姓名：___________班级：___________考号：___________一、阅读理解The Cool 2022 Travel DestinationsNational Geographic’s new list of the most amazing places to visit in 2022, “Best of World 2022” is an inviting mixture of global destinations that will inspire your appetite for travel in the New Year.NatureOur global editors picked the planet's 25 most exciting destinations for 2022! There is really something to appeal to everyone.The best places to enjoy nature include Northern Minnesota, which offers skies filled with thousands of shining stars as it has little or no light pollution.AdventureOne of the inspiring adventure ideas is an invitation to cycle a new bike trail. The route of the Paris to the sea La Seine à Vélo trail passes the house and famous water lilies (水仙) of Impressionist painter Claude Monet in Giverny.Culture and HistoryThis brand new 2022 list also celebrates several destinations recommended by UNESCO in honor of how UNESCO has been helping protect cultural and national treasures for 50 years.This selection of cultural centers takes in Procida, an island city located 40 minutes southwest of Naples by boat. This city, famous for its colorful buildings, plans to use its year to bring people a sense of community. Its year-long festival aims to encourage responsible travel throughout the year, and to avoid a crowd of visitors during the summer as happened in the past.FamilyThe best places for families include astonishing settings in the US and further away. One of these is Granada in Spain.At this palace, kids of all ages and their parents can appreciate the unique patterns and designs that promise “A colorful classroom for age-appropriate exploration of math conceptssuch as shapes, proportion (比例), and measurement”.1．Why does National Geographic offer the “Best of World 2022” ?A．To attract people to enjoy delicious food.B．To invite people to find amazing places.C．To explore the most exciting destinations.D．To increase people’s interest in traveling.2．What is the disadvantage of visiting the cultural centers in the past?A．It’s inconveniently located.B．There were too many people.C．Travelers were not responsible.D．Its colorful buildings faded away.3．What kind of destination best suits children who are interested in maths? A．Nature.B．Adventure.C．Culture and History.D．Family.There is no such thing as a perfect woman, and Nothing but Thirty screenwriter Zhang Yingji wanted to convey this message in telling the stories of three different women, who have found very different ways to climb their own mountains.Wang Manni is a woman who will climb any mountain as long as she finds it challenging. Zhong Xiaoqin is one who will only climb if she has someone to go along with her. She will not overexert herself, and she will definitely stop once she has reached a comfortable place. Gu Jia, on the other hand, has already started to think about reaching the peak before she even starts the climb, regardless of whether she is alone or has company.In a sense, the scriptwriter purposely created Gu Jia as the perfect woman of thirty. She is married, with a successful husband and a young son. She is living the dream, but Gu Jia does not feel complete. She feels lost. She is flawed. She has episodes of succumbing to her own greed and disregard to those around her.“She is someone who chases alter perfection.” said Tong Yao (who portrays Gu Jia). “Obviously, this is stressful for those around her. She hides things. She isn’t perfect, but in front of others, she has to stay perfect.”Her chase for perfection and her stubbornness to maintain this image has effected many of the relationships in her life. She chases after what she believes is right for others. Because of this, she and her husband start to see and value things differently, which puts a strain on their relationship.Gu Jia’s personal struggles give life to the character. Many viewers are able to relate to her, and, through her character, find a shadow of themselves. There’s still a lot left that we can learn from the women of Nothing but Thirty, but maybe like them, we too can find the courage in ourselves to walk on that road which is truly meant for us.4．According to the article, which of the following best describes Zhong Xiaoqin’s personality?A．Ambitious and goal-driven B．Moderate and contentC．Aimless and impulsive D．Visionary and independent 5．According to Paragraph 3, what is not true about Gu Jia’s life?A．She has her own worries and insecurities.B．She leads a seemingly perfect and enviable life.C．She can be greedy and insensitive to others’ feelings.D．She is discontented with life because of her husband.6．According to the passage, audiences have a preference for Gu Jia mainly because she________.A．is a perfectionist B．stands up to her husband C．balances her work and life well D．displays some identifiable traits 7．What is the main purpose of this passage?A．To call attention to the rise of feminism.B．To introduce the plot of Nothing but Thirty.C．To contrast the main characters of Nothing but Thirty.D．To encourage viewers to find inspiration in Nothing but Thirty.Are you a tea drinker? If so, you’re not alone. Every day around the world millions of cups of this popular brew are drunk, and it’s been that way for thousands of years. The oldest discovered tea is from the Han Dynasty, dating from 206BC to 220AD．But it’s thought that the tea trend really took off during the Tang Dynasty in the 8th Century, when it became China’s national drink. Now, Turkey, the Republic of Ireland and the UK are believed to bethe biggest tea—drinking nations, per capita.Tea is consumed in many ways-slurped, sipped or glugged. It can be poured from pots, infused or brewed in the cup using tea bags—and it’s this latter process that is causing concern. Research last year found some premium tea bags might be leaving billions of microscopic plastic particles in the cup. Scientists from McGill University in Montreal found that some ‘plastic’ tea bags shed high levels of micro plastics into water. However, The World Health Organization says such particles in drinking water do not appear to pose a risk.Most tea bags are made from paper, with a small amount of plastic used to seal them shut— made from oil. This has led to debate about whether they can be recycled, but many are still composted. However, gardener Mike Armitage has told the BBC that the plastic contained in the soil could be washed into streams and rivers and ultimately out to sea.Unilever, the owners of the tea brand PG Tips, said their tea bags are made with a small amount of plastic—used to seal them—and that they are suitable for composting. And the brand Yorkshire Tea said their bags do contain 25% polypropylene, but they were “actively developing plant—based and biodegradable alternatives”.While tea bag manufacturers might be doing their bit to reduce plastic pollution, it could be a good time to switch your favourite beverage to coffee, or if that isn’t your cup of tea then try using loose-leaf tea, which can have a better flavour.8．What is the main idea of paragraph 2?A．Tea can be consumed in many ways.B．The use of tea bags doesn’t appear to pose a riskC．The use of tea bags is causing concern.D．Some tea bags might be leaving microscopic plastic particles in the cup.9．What is not a possible solution to the problem caused by tea bags?A．reduce the amount of plastic used to seal tea bagsB．wash the plastic in the soil into streams, rivers and seaC．develop plant-based and biodegradable alternativesD．switch to coffee or try to use loose-leaf tea10．What is the author’s attitude towards the use of tea bags?A．Supportive B．Indifferent C．Opposed D．Neutral 11．What could be the best title for the text?A．Potential Plastic PollutionB．Chinese tea cultureC．What is your favorite drink?D．The Humble tea bagUsing the power of artificial intelligence (AI), scientists have revealed new insights into the creation and destruction of mass extinction. Contrary to conventional knowledge, their study suggests that larger extinctions are not always a form of “creative destruction” that allows new organisms (生物体) to radiate and evolve. Instead, it suggests that mass extinction is rarely associated with new species of radiation.Dr. Hoyal Cuthill, the lead study author from the University of Essex in the UK and the Tokyo Institute of Technology, said in a statement, “Some of the most challenging things to understand the history of life are the vast timelines involved and the number of species. New machine learning applications can help us understand this information in human-readable form. This means that we can, so to speak, hold the evolution of half a billion years in the palm of our hand and gain new insights from what we see.”They concluded that mass extinction and later radiation were not connected as previously thought. Within 5 percent of the most significant periods of disruption (中断), AI detected “big five” mass extinctions, seven more mass extinctions, two massextinction-radiation events, and 15 mass radiations. Most importantly, it discovers that massive radiation and extinction rarely occurred with each other, changing the view that greater extinction leads to a kind of deep cycle-like species radiation of nature. It appears that larger extinctions are certainly not the engine of evolutionary radiation. Take the Cambrian eruption for example and it was about 41 million years ago when a large group of animals first appeared on the record of the first fossil record and the dawn of a high mobile animal equipped with modern physical features.This new study found that a handful of other notable explosions of biodiversity, including the Cambrian eruption, usually occurred at a time when they were largely isolated (隔离) from extinction. Dr. Nicholas Guttenberg, a study co-author from the Tokyo Institute of Technology explained, “Ecosystems are dynamic and you don’t need anything to exist to allow something new to appear.”12．What does the first paragraph serve as?A．An explanation of artificial intelligence.B．A background of researchers’ study.C．The reasons for creative destruction.D．The result of researchers’ new study. 13．What can we infer from Dr. Hoyal Cuthill’s words?A．AI contributes a lot to the study of evolution.B．Understanding the history of life is very difficult.C．New AI machines learn applications better.D．Biological evolution can be controlled easily.14．What is the researchers’ discovery?A．Mass extinction is unlikely to cause evolutionary radiation.B．The first animal with modern features occurred during eruption.C．The volcanic eruption led to a mass extinction and radiation.D．The idea of deep cycle-like species radiation has turned out true.15．What is the text mainly about?A．New processes of biological evolution.B．New view of radiation from natural species.C．New understanding of mass extinction.D．New outbreaks of biological populations.二、七选五Which is more effective, group studying or studying alone?We’ve all experienced getting together with classmates to study for an upcoming exam and spending the entire time talking or joking around. You leave the group without accomplishing anything to get you ready for your exam.____16____. The following are some benefits of studying alone.____17____When you lock yourself away in your room, there tend to be less distractions than when you are studying in a group. Nobody is moving around or talking near you. There are literally no distractions, unless you’re the one who feels the need to clean everything when you study.Personal study environmentEveryone is different, which means everyone learns differently. You may require classical music, a comfortable room, and a cup of tea while you study. Someone else may require complete silence, and no snacks at all.____18____ Studying alone also allows you to use the study strategies that are the most effective for your learning style. Some students learnbest with flashcards, while others learn best when they reread chapters. ____19____ Personalize learning contentThere may be some topics in class that you really need to work on. ____20____. Besides, you can tailor learning methods by studying alone while group studying can’t. More crucially, you can consolidate the topics that are difficult to you over and over.A．You can learn whatever you like.B．Minimum distractions.C．That is what you can’t achieve in group studying.D．Find your learning style, and you can get better results.E．Only when you study alone, you’ re able to focus on exactly those topics.F．So if you are the one who can be so distracted, it’s strongly recommended that you should study alone.G．Studying alone allows you to set the perfect study environment so you get the most out of studying.三、完形填空As the late afternoon sun beat down, Brandon finished feeding his cows and decided to call it a day. His two sons, Louie, 6, and Everette, 3, had tagged along.As they ____21____ the house, the two boys ran ahead of their father. Unfortunately, Louie fell into a well for the board covering it had, over time, grown ____22____.When Brandon realized what had happened, he ran to the well, and instinctively, he jumped in. With several desperate ____23____ he grabbed Louie, who was ____24____. However, there was no way they could climb out.Looking up to see Everette, who was looking down at them from the ____25____ of the well, Brandon shouted, “Everette, you’re going to have to be a big boy and save us. Run to the road and ____26____ the mailbox until someone stops. Tell them we need help.” Everette did as he was told.Minutes passed like hours as Brandon and his trembling son waited for ____27____. Finally, Everette’s face appeared ____28____ the well. “Daddy, are you still down that hole?”“Yes. Did you get some help?”“No.”Brandon’s heart ____29____. “That’s OK, honey. But you have to go back out to the road and get someone to stop. OK, Everette?”“Ok, Daddy.”About 15 minutes later, Christi and Mark Mckenney were driving by ____30____ they noticed Everette. They ____31____ and asked if he was OK. “My daddy’s in a hole,” he told them.The couple piled Everette into their pickup and drove onto the ____32____, and the boy pointed them to the well. Forty—some minutes after he’d jumped into the well, Brandon and his son were eventually saved. Other than some slight ____33____, Brandon was fine, but Louie suffered hypothermia (体温过低). ____34____, he was healthy enough to return to school a week later.While the rescuers have been hailed as heroes, Mark isn’t ____35____ it. “We’re just neighbors helping neighbors. If there is a hero in this story, it’s three-year-old Everette. He’s a real lifesaver.”21．A．accounted B．allowed C．headed D．catered 22．A．fragrant B．fragile C．furious D．flexible 23．A．achievements B．attempts C．attacks D．arguments 24．A．alarmed B．amazed C．amused D．ashamed 25．A．inside B．opposite C．base D．top 26．A．stand by B．stick with C．draw on D．sort out 27．A．occasion B．rescue C．despair D．refuge 28．A．below B．near C．above D．beside 29．A．bled B．suffered C．exploded D．sank 30．A．when B．while C．as D．until 31．A．pulled away B．pulled over C．pulled together D．pulled back 32．A．farm B．road C．house D．board 33．A．infection B．twist C．scratches D．fantasy 34．A．Otherwise B．Moreover C．Still D．Therefore 35．A．making B．catching C．getting D．buying四、用单词的适当形式完成短文阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。

托福TPO7阅读原文及参考答案Part1托福TPO是我们托福阅读的重要参考资料，为了方便大家备考，下面小编给大家整理了托福TPO1阅读文本及题目答案Part2，希望大家喜欢。

托福TPO7阅读原文Part1The Geologic History of the MediterraneanIn 1970 geologists Kenneth J. Hsu and William B.F. Ryan were collecting research data while aboard the oceanographic research vessel Glomar Challenger. An objective of this particular cruise was to investigate the floor of the Mediterranean and to resolve questions about its geologic history. One question was related to evidence that the invertebrate fauna (animals without spines) of the Mediterranean had changed abruptly about 6 million years ago. Most of the older organisms were nearly wiped out, although a few hardy species survived. A few managed to migrate into the Atlantic. Somewhat later, the migrants returned, bringing new species with them. Why did the near extinction and migrations occur?Another task for the Glomar Challenger's scientists was to try to determine the origin of the domelike masses buried deep beneath the Mediterranean seafloor. These structures had been detected years earlier by echo-sounding instruments, but they had never been penetrated in the course of drilling. Were they salt domes such as are common along the United States Gulf Coast, and if so, why should there have been so much solid crystalline salt beneath the floor of the Mediterranean?With question such as these clearly before them, the scientists aboard the Glomar Challenger processed to the Mediterranean to search for the answers. On August 23, 1970,they recovered a sample. The sample consisted of pebbles of hardened sediment that had once been soft, deep-sea mud, as well as granules of gypsum and fragments of volcanic rock. Not a single pebble was found that might have indicated that the pebbles came from the nearby continent. In the days following, samples of solid gypsum were repeatedly brought on deck as drilling operations penetrated the seafloor. Furthermore, the gypsum was found to possess peculiarities of composition and structure that suggested it had formed on desert flats. Sediment above and below the gypsum layer contained tiny marine fossils, indicating open-ocean conditions. As they drilled into the central and deepest part of the Mediterranean basin, the scientists took solid, shiny, crystalline salt from the core barrel. Interbedded with the salt were thin layers of what appeared to be windblown silt.The time had come to formulate a hypothesis. The investigators theorized that about 20 million years ago, the Mediterranean was a broad seaway linked to the Atlantic by two narrow straits. Crustal movements closed the straits, and the landlocked Mediterranean began to evaporate. Increasing salinity caused by the evaporation resulted in the extermination of scores of invertebrate species. Only a few organisms especially tolerant of very salty conditions remained. As evaporation continued, the remaining brine (salt water) became so dense that the calcium sulfate of the hard layer was precipitated. In the central deeper part of the basin, the last of the brine evaporated to precipitate more soluble sodium chloride (salt). Later, under the weight of overlying sediments, this salt flowed plastically upward to form salt domes. Before this happened, however, the Mediterranean was a vast desert 3,000 meters deep. Then, about 5.5 million years ago came the deluge. As a result of crustaladjustments and faulting, the Strait of Gibraltar, where the Mediterranean now connects to the Atlantic, opened, and water cascaded spectacularly back into the Mediterranean. Turbulent waters tore into the hardened salt flats, broke them up, and ground them into the pebbles observed in the first sample taken by the Challenger. As the basin was refilled, normal marine organisms returned. Soon layer of oceanic ooze began to accumulate above the old hard layer.The salt and gypsum, the faunal changes, and the unusual gravel provided abundant evidence that the Mediterranean was once a desert.gypsum: a mineral made of calcium sulfate and waterParagraph 1: In 1970 geologists Kenneth J. Hsu and William B.F. Ryan were collecting research data while aboard the oceanographic research vessel Glomar Challenger. An objective of this particular cruise was to investigate the floor of the Mediterranean and to resolve questions about its geologic history. One question was related to evidence that the invertebrate fauna (animals without spines) of the Mediterranean had changed abruptly about 6 million years ago. Most of the older organisms were nearly wiped out, although a few hardy species survived. A few managed to migrate into the Atlantic. Somewhat later, the migrants returned, bringing new species with them. Why did the near extinction and migrations occur?托福TPO7阅读题目Part11. The word "objective" in the passage is closest in meaning to○achievement○requirement○purpose○feature2. Which of the following is NOT mentioned in paragraph 1 as a change that occurred in the fauna of the Mediterranean?○Most invertebrate species disappeared during a wave of extinctions.○A few hardy species wiped out many of the Mediterranean's invertebrates.○Some invertebrates migrated to Atlantic Ocean.○New species of fauna populated the Mediterranean when the old migrants returned.Paragraph 3: With question such as these clearly before them, the scientists aboard the Glomar Challenger processed to the Mediterranean to search for the answers. On August 23, 1970, they recovered a sample. The sample consisted of pebbles of hardened sediment that had once been soft, deep-sea mud, as well as granules of gypsum and fragments of volcanic rock. Not a single pebble was found that might have indicated that the pebbles came from the nearby continent. In the days following, samples of solid gypsum were repeatedly brought on deck as drilling operations penetrated the seafloor. Furthermore, the gypsum was found to possess peculiarities of composition and structure that suggested it had formed on desert flats. Sediment above and below the gypsum layer contained tiny marine fossils, indicating open-ocean conditions. As they drilled into the central and deepest part of the Mediterranean basin, the scientists took solid, shiny, crystalline salt from the core barrel. Interbedded with the salt were thin layers of what appeared to be windblown silt.3. What does the author imply by saying "Not a single pebble was found that might have indicated that thepebbles came from the nearby continent"?○The most obvious explanation for the origin of the pebbles was not supported by the evidence.○The geologists did not find as many pebbles as they expected.○The geologists were looking for a particular kind of pebble.○The different pebbles could not have come from only one source.4.Which of the following can be inferred from paragraph 3 about the solid gypsum layer?○It did not contain any marine fossil.○It had formed in open-ocean conditions.○It had once been soft, deep-sea mud.○It contained sediment from nearby deserts.5. Select the TWO answer choice from paragraph 3 that identify materials discovered in the deepest part of the Mediterranean basin. To receive credit you must select TWO answers.○Volcanic rock fragments.○Thin silt layers○Soft, deep-sea mud○Crystalline salt6. What is the main purpose of paragraph 3?○To describe the physic al evidence collected by Hsu and Ryan○To explain why some of the questions posed earlier in the passage could not be answered by the findings of the Glomar Challenger○To evaluate techniques used by Hsu and Ryan to explore the sea floor○To describe the m ost difficult problems faced by the GlomarChallenger expeditionParagraph 4: The time had come to formulate a hypothesis. The investigators theorized that about 20 million years ago, the Mediterranean was a broad seaway linked to the Atlantic by two narrow straits. Crustal movements closed the straits, and the landlocked Mediterranean began to evaporate. Increasing salinity caused by the evaporation resulted in the extermination of scoresof invertebrate species. Only a few organisms especially tolerant of very salty conditions remained. As evaporation continued, the remaining brine (salt water) became so dense that the calcium sulfate of the hard layer was precipitated. In the central deeper part of the basin, the last of the brine evaporated to precipitate more soluble sodium chloride (salt). Later, under the weight of overlying sediments, this salt flowed plastically upward to form salt domes. Before this happened, however, the Mediterranean was a vast desert 3,000 meters deep. Then, about 5.5 million years ago came the deluge. As a result of crustal adjustments and faulting, the Strait of Gibraltar, where the Mediterranean now connects to the Atlantic, opened, and water cascaded spectacularly back into the Mediterranean. Turbulent waters tore into the hardened salt flats, broke them up, and ground them into the pebbles observed in the first sample taken by the Challenger. As the basin was refilled, normal marine organisms returned. Soon layer of oceanic ooze began to accumulate above the old hard layer.7. According to paragraph 4, which of the following was responsible for the evaporation of the Mediterranean's waters?○The movements of Earth's crust○The accumulation of sediment layers○Changes in the water level of the Atlantic Ocean○Changes in Eart h's temperature8. The word "scores" in the passage is closest in meaning to○members○large numbers○populations○different types9. According to paragraph 4, what caused most invertebrate species in the Mediterranean to become extinct?○The evaporation o f chemicals necessary for their survival ○Crustal movements that connected the Mediterranean to the saltier Atlantic○The migration of new species through the narrow straits○Their inability to tolerate the increasing salt content of the Mediterranean10. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.○The strait of Gibraltar reopened when the Mediterr anean and the Atlantic became connected and the cascades of water from one sea to the other caused crustal adjustments and faulting.○The Mediterranean was dramatically refilled by water from the Atlantic when crustal adjustments and faulting opened the Strait of Gibraltar, the place where the two seas are joined.○The cascades of water from the Atlantic to the Mediterranean were not as spectacular as the crustal adjustments and faulting that occurred when the Strait of Gibraltar was connected to those seas.○As a result of crustal adjustments and faulting and thecreation of the Strait of Gibraltar, the Atlantic and Mediterranean were connected and became a single sea with spectacular cascades of water between them.11. The word "Turbulent" in the passage is closest in meaning to○Fresh○Deep○Violent○TemperateParagraph 2 ■Another task for the Glomar Challenger's scientists was to try to determine the origin of the domelike masses buried deep beneath the Mediterranean seafloor. ■These structures had been detected years earlier by echo-sounding instruments, but they had never been penetrated in the course of drilling. ■Were they salt domes such as are common along the United States Gulf Coast, and if so, why should there have been so much solid crystalline salt beneath the floor of the Mediterranean? ■12. Look at the four squares [■] that indicate where the following sentence could be added to the passage.Thus, scientists had information about the shape of the domes but not about their chemical composition and origin.Where would the sentence best fit?13.Direction: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some sentences do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points.An expedition to the Mediterranean answered some long-standing questions about the ocean's history.●●●Answer choices○The Glomar Challenger expedition investigated changes in invertebrate fauna and some unusual geologic features.○Researchers collected fossils to determine which new species migrated from the Atlantic with older species.○Scientists aboard the Glomar Challenger were the first to discover the existence of domelike masses underneath the seafloor.○Samples recovered from the expedition revealed important differences in chemical composition and fossil distribution among the sediment layers.○Evidence collected by the Glomar Challenger supports geologists' beliefs that the Mediterranean had evaporated and become a desert, before it refilled with water.○Mediterranean salt domes formed after crustal movements opened the straits between the Mediterranean and the Atlantic, and the Mediterranean refilled with water.托福TPO7阅读答案Part1参考答案：1.○ 32.○ 23.○ 14.○ 15.○ 2, 46.○ 17.○ 18○ 29.○ 410.○ 211.○ 312.○ 313. The Glomar ChallengerSamples recovered fromEvidence collected by托福TPO7阅读原文翻译Part1参考翻译：地中海的地质历史1970年，地理学家Kenneth J. Hsu 和 William B.F. Ryan在海洋调查船Glomar Challenger号上收集调研资料。

继电保护英文中文对照表1－58：A 296－311：G 386－417：M 588－667：S 59－107:B 312－327:H 418－432：N 668－722：T 108－184:C 328－363：I 433－468：O 723－737：U 185－229：D 364：J 469－542:P 738－754：V 230－258:E 365：K 543－545:Q 755－762:W 259－295:F 366－385：L 546－587；R 763－771:Z序号英文全称中文解释1 A lagging power-factor 滞后的功率因数2 A mutualky induced e。

m。

f 互感电动势3 a retarding torque 制动转矩4 Abnormal operating condition 不正常运行状态5 Abnormal overload 异常过载6 Abnormal overvoltage 事故过电压7 Abnormal state 非常态8 Above earth potential 对地电势9 Abrupt signal analysis 突变信号分析10 Absolute potential 绝对电势11 AC circuit breaker 交流断路器12 AC component 交流分量13 AC directional over current relay 交流方向过流继电器14 AC distribution system 交流配电系统15 AC reclosing relay 交流重合闸继电器16 Accelerating protection forswitching onto fault 重合于故障线路加速保护动作17 Acceleration Trend Relay（A TR）加速趋势继电器18 Accurate Working Current 精确工作电流19 Accurate Working voltage 精确工作电压20 Activate the breaker trip coil 起动断路器跳闸21 Adaptive features 自适应特性22 Adaptive relay protection 自适应继电保护23 Adaptive relaying 自适应继电保护24 Adaptive segregated directionalcurrent differential protection 自适应分相方向纵差保护25 Admittance relays 导纳型继电保护装置26 AI(artificial intelligence) 人工智能27 Air brake switch 空气制动开关28 Air breaker 空气断路器29 Air—blast circuit breaker 空气灭弧断路器30 Air-blast switch 空气吹弧开关31 Air-space cable 空气绝缘电缆32 Alarm 报警33 Alarm relay 报警信号继电器34 Alarm signal;alerting signal 报警信号35 Alive 带电的36 All—relay interlocking 全部继电连锁37 All—relay selector 全继电式选择器38 Amplitude Comparison 绝对值比较39 Analogue 模拟40 Angle of maximum sensitivity 最大灵敏角41 Annunciator relay 信号继电器42 Approximation component 逼近分量43 Arc extinguishing coil 灭弧线圈44 Arc suppressing coil 消弧线圈45 Arc suppressing reactor 灭弧电抗器46 Arcing fault 电弧接地故障47 Armature 电枢48 Asymmetric load 不对称负载49 Asymmetric short circuit 不对称短路50 Asynchronous resistance 异步电阻51 Asynchronous tractance 异步电抗52 Attacted armature relay 衔铁（磁铁）吸合式继电器53 Automatic quasi-synchronization 自动准同步54 Automatic reclosure 自动重合闸55 auto-put-into device of reserve—source 备用电源自动投入装置56 auto-recosing with self-synchronism 自同步重合闸57 Auxiliary contacts 辅助触点58 Auxiliary relay/intermediate relay 辅助继电器／中间继电器59 B sampling function B样条函数60 Back-spin timer 反转时间继电器61 Back—up over—speed governor 附加超速保护装置62 Back-up protection 后备保护63 Back—up ssystem 后备继电保护64 Biased differential relaying 极化差动继电保护系统65 Bi-directional relay 双向继电器66 Bi-stable 双稳态67 Black-out area 停电区68 Black-start 黑启动69 Blinker 继电器吊牌70 Bloching protection 闭锁式保护71 Blocking relay 连锁继电器72 Blocking signal 闭锁信号73 Blow—out coil 灭弧线圈74 Branch coefficient 分支系数75 Breaker contact point 断路器触点76 Breaker pount wrench 开关把手77 Breaker trip coil 断路器跳闸线圈78 Brushless excitation 无刷励磁79 Buchholtz protecter 瓦斯保护80 Bundle factor 分裂系数81 Bundle-conductor spacer 分裂导线82 Bus bar 母线;导电条83 Bus bar current transformer 母线电流变压器84 Bus bar disconnecting swich 分段母线隔离开关85 Bus compartment 母线室；汇流条隔离室86 Bus coupler CB 母联断路器87 Bus duct 母线槽;母线管道88 Bus hub 总线插座89 Bus insulator 母线绝缘器90 Bus line 汇流线91 Bus protection（Bus—bar protection）母线保护92 Bus protective relay 母线保护继电器93 Bus reactor 母线电抗器94 Bus request cycle 总线请求周期95 Bus rings 集电环96 Bus rod 汇流母线97 Bus section reactor 分段电抗器98 Bus structure 母线支架；总线结构99 Bus tie switch 母线联络开关100 Bus—bar chamber 母线箱101 Bus—bar fault 母线故障102 Bus—bar insulator 母线绝缘子103 bus—bar protection withfixed circuit xonnection 固定联结式母线保护104 Bus-bar sectionalizing switch 母线分段开关105 Bushing 套管106 bushing type xurrent transformer 套管式电流互感器107 Bypass 旁路108 Cable relay 电缆继电器109 Capacitance 电容110 Capacitance effect 电容效应111 Capacitance relay 电容继电器112 Capacitive current 电容电流113 Capacitor 电容器114 Capacitor of series compensation 串补电容115 Capacity charge 电容充电116 Capacity ground 电容接地117 Carrier channel 高频通道118 Carrier or pilot—wire receiver relay 载波或导引线接受继电器119 Carrier receiver 发讯机120 Carrier transmitter 收讯机121 Cascading outages 连锁故障122 Catch net （protecting net）保护网123 Chatter 颤振124 Circuit breaker 断路器125 Circuit breaker failure protection 断路器失灵保护126 Circuit control relay 电路控制继电器127 Clip-on leads 夹式引线128 Clock 时钟129 Close by local protection 保护合闸130 Close—up fault 近距离故障131 Closing coil 合闸线圈132 Closing relay 合闸继电器133 Coil adjuster 线圈调节器134 Coil curl 线圈135 Coil current 线圈电流136 Coil end leakage reactance 线圈端漏电抗137 Coil factor 线圈系数138 coil inductance 线圈电感139 Combined bus and transformer protection 母线和变压器共用保护140 Commissioning 投运141 Common-mode voltage 共模电压142 Communication channel 通讯通道143 Communication interface 通讯接口144 Compensation theorem（compensation principle) 补偿原理145 Compensation voltage（compensating voltage）补偿电压146 Compound relay 复合继电器147 Concentrated coil 集中绕组148 Concussion 震动149 Conductance relay 电导继电器150 Configuration control 组态控制151 Connection with 90degree ９０度接线152 Constant 常量153 Contact 触点154 Contact bounce 触点颤动155 Contact multiplying relay 触点多路式继电器156 Continuous load 持续负载157 Continuous rating 连续运行的额定值158 Converter relay 换流器继电器159 Coordination of relay settings 保护的整定配合160 Coordination time interval 保护配合时间阶段161 Core 铁芯162 Counting relay 计数继电器163 Coupler 耦合器164 Critical clearing time 极限切除时间165 Cross—country faults “越野式”双相同时接地故障166 Crystal can relay 晶体密闭继电器167 CT line-break ＣＴ断线168 Current actuated leakage protector 电流起动型漏电保护器169 Current attenuation 电流衰减170 Current balance type currentdifferential relay 电流平衡式差动电流继电器；差动平衡式电流继电器171 Current changer 换流器172 Current compensational ground distance relay 电流补偿式接地远距继电器173 Current consumption 电流消耗174 Current differential criterion 电流差动判据175 Current transformer 电流互感器176 Current transformer phase angle 电流互感器相角177 Current transformer saturation 电流互感器的饱和问题178 Current traveling wave 电流行波179 Current-balance relay 电流平衡式继电器180 Current-limiting relay 限流继电器181 Cut—off of supply 停止供电182 Cut—off push 断路器按钮183 Cut—off relay 断路继电器184 Cut—out relay 短路继电器185 Damping circuit 阴尼电路186 Dash current 冲击电流187 Data medium 数据载体188 Data processing 数据处理189 Data transmission 数据传输190 Dead zone(Blind spot）死区191 Definite time 定时限192 Definite time relay 定时限继电器193 Delay—action relay 缓动继电器194 Delta 三角形195 Differential mode interference 差模干扰196 Differential motion 差动197 Differential protection 差动保护198 Differential protection withpercentage restraining 具有比率制动的差动继电器199 Differential relay 差动继电器200 Differential relay with fast saturatedcurrent transformer带有速饱和变流器的差动继电器201 Differential relay with RestraintCharacteristic 具有制动特性的差动继电器202 Digital protection 数字式保护203 Digital signal processor 数字信号处理器204 Direct axis 直轴205 Directional contact 方向触点206 Directional distance relay 方向距离继电器207 Directional over-current protection 方向过流保护208 Directional over—current relay 方向过流继电器209 Directional pilot relaying 方向纵联继电保护210 Directional protection 方向保护211 Direct-to—ground capacity 对地电容212 Discharge 放电213 Disconnecting switch 隔离开关214 Discontinuous relay 鉴别继电器215 Discriminating zone 判别区216 Dislocation 损失、故障引起的混乱217 Disruption 瓦解、系统解列218 Distance protection 距离保护219 Distance relay（impedance relay) 阻抗继电器220 Distributed capacitance of long line 长线分布电容221 Distribution feeder 配电馈线222 Diviation character 偏移特性223 Double bus bar protection 双母线保护224 Double-ended clip—on leads 双头夹式引线225 Dropout current 回动电流226 Dry-type transformer 干式变压器227 Dual bus 双总线228 Dynamic attributes 动态特性229 Dynamoelectric relay 电动式继电器230 Earth fault 接地故障231 Earth—leakage protection 对地漏电保护232 Economic dispatch system 经济调度系统233 Electric capacity 电容234 Electric interlock relay 连锁继电器235 Electric reset relay 电复位式继电器236 Electrical apparatus（equipments）电器设备237 Electrical governing system 电力调速系统238 Electrical network(power network）电网239 Electrically operated valve 电动阀门240 Electro polarized relay 极化继电器241 electrolyte 电解质242 Electromagnetic brake 电磁制动243 Electromagnetic torque 电磁转矩244 Electromagnetical relay 电磁式继电器245 Electromechanic relay 机电的246 Electromotive force 电动势247 Emergency service 事故运行248 Emergency standby 事故备用249 Energy direction relay 能量方向继电器250 Equivalent circuit 等值电路251 Escapement/interlock/blocking 闭锁252 Excitation—loss relay 失磁继电器253 Expert system 专家系统254 Extermal characteristics 外特性255 Extinction coil 消弧线圈256 Extinguishing voltage 灭弧电压257 Extra high voltage 超高压258 Extra-high—voltage transmission line 超高压传输259 Fail safe interlock 五防装置260 Fail—safe unit 五防261 Failure rate 故障率262 False tripping 误动263 Fast ersponse 快速响应264 Fast—operate slow-release relay 快动缓释继电器265 Fast—release relay 快释放继电器266 Fault clearing time 故障切除时间267 Fault component 故障分量268 Fault detecting relay 故障检测继电器269 Fault diagnosis 故障诊断270 Fault line 故障线271 Fault location 故障定位272 Fault phase selection 故障选相273 Fault phase selector 故障选线元件274 Fault recorder 故障录波器275 Fault type 故障类型276 Fault-component algorithms 故障分量算法277 Faulted phase identification 故障相识别元件278 Faults recorder 故障录波279 Feedback 反馈280 Feeder 馈电线281 Fiber optical communication 光纤通信282 Fiber—Optic Pilot 光纤纵联保护283 Field application relay 励磁继电器；激励继电器284 Field failure protection of generator 发电机的失磁保护285 Field test 实地试验286 Filter 滤波器287 Finger 触点的接点288 Fourier algorithm 傅立叶算法289 Free—standing 独立的；无需支撑物的290 Frequency component 频率分量291 Frequency response 频率响应292 Frequency sensing 频率测量293 Frequency window 频窗294 Full—wave phase comparison protection 全波相位比较保护295 Fuse box（Fusible cutout）熔断器296 Gaseous shield 瓦斯保护装置297 Gas-Insulater switchgear GIS 气体绝缘组合电器298 Generator 发电机299 Generator cutout relay 发电机断路继电器300 Generator Negative Current Protection 发电机负序电流保护301 Generator out of step protection 发电机失步保护302 Generator protection 发电机保护303 Generator protection for negativesequence current 发电机负序电流保护304 Generator stator single phase earth fault 发电机定子绕组单相接地保护305 Generator stator winding short circuit faults 发电机定子绕组短路故障306 Generator-transformer set 发电机－变压器组307 Graded time settings 阶梯型时间配置308 Grading 等级309 Ground fault relay 接地故障继电器310 Ground—fault of ungrounded system 小电流接地系统311 Grounding apparatus 接地装置312 Half—cycle integral algorithm 半周积分算法313 Hard strap 硬压板314 Harmonic current 正弦电流315 Harmonic restraining 谐波制动316 Healthy phases 非故障相317 Heavy load 重负荷318 Hidden failures 隐形故障319 High impedance busbar differetial protection 高阻抗母线差动保护320 High resistance 高阻321 High sensitive relay 高灵敏度继电器322 High speed impedance relay 高速阻抗继电器323 High speed signal acquisition system 高速数字信号采集系统324 High tension electrical porcelain insulator 高压电瓷绝缘子325 High voltage line 高压线路326 High—frequency direction finder 高频测向器327 High-voltage relay 高压继电器328 Immune to electromagnetic interference 不受电磁干扰329 Impedance circle 阻抗圆330 Impedance compensator 阻抗补偿器331 Impedance converter 阻抗变换器332 Impedance mismatch 阻抗失配333 Impulsing relay 冲击继电器334 Inadvertent energization 过激磁335 Incorrect tripping 误动336 Inductance couping 电感耦合337 Induction coefficient 感应系数338 Induction cup relay 感应杯式继电器339 Induction disc relay 感应圆盘式继电器340 Induction type relay 感应式继电器341 Inductor 电感342 Infeed current 助增电流343 Inrush exciting current of transformer 励磁涌流344 Instantaneous protection 瞬时保护345 Instantaneous under voltageprotection with current supervision 电流闭锁电压速断保护346 Insulation supervision device 绝缘监视347 Insulator 绝缘子348 Insulator arcing horn 绝缘子角形避雷器349 Insulator arc—over 绝缘子闪络350 Insulator bracket 绝缘子托架351 Insulator cap 绝缘子帽352 Insulator chain 绝缘子串353 Inter turn faults 匝间短路354 Interlock 连锁355 Intermittent fault 间歇故障356 Intermittent fillet weld 间接角缝焊接357 Internal fault 内部故障358 Internal resistance 内阻359 Interrupting time 断路时间360 Intertripping underreach protection 远方跳闸欠范围保护361 Inverse phase sequence protection 逆相序保护362 Inverse power protection 逆功率保护363 Isolated neutral system 中性点绝缘系统364 Jumper connection 跳线365 Kalman filter algorithm 卡尔曼滤波算法366 Laplace and Fourier transforms 拉氏和傅里叶变换367 Leased line 租用线路368 LED 发光二极管369 Line trap 线路陷波器370 Load characteristic 负载特性371 Load flow calculations 潮流计算372 Load patterns 负荷形式373 Load schedule according to frequency change 按周波减载374 Load shedding 甩负荷375 Lockout relay 闭锁出口继电器376 Locus of measured impedance 测量阻抗轨迹377 Longitudinal differential protection 纵联差动保护378 Longitudinal differential relay 纵联差动继电器379 Loss of synchronism protection 失步保护380 Low impedance busbar protection 低阻抗母线保护381 Low—frequency component,subharmonic 低频分量,低次谐波382 Low-frequency high—voltage protection 低频高压试验383 Low-voltage protection 低压保护384 Low—voltage rekease relay 低压释放继电器385 Low—voltage relay 低压继电器386 Magnetic flux 磁通387 Magnetic induction 磁感应强度388 Magnetization curve 磁化曲线389 Magnetizing 磁化390 Magnetizing inrush current 劢磁涌流391 Magnitude of current 电流幅值392 Main protection 主保护393 Manipulating organ 操作单元394 Manipulation 操作395 Man—machine interface 人机对话接口396 Margin 裕度397 Measured impedance 测量阻抗398 Measurement 测量399 Measurement signal 测量信号400 Measuring unit 测量元件401 Mechanism latch 机械锁402 Memory circuit 记忆回路403 Metallic fault 金属性故障404 Micro—processor based protective relay 微机继电保护405 Microwave link protection 微波保护406 Minimum load impedance 最小负荷阻抗407 Motor-field failure relay 电动机磁场故障继电器408 Moving coil relay 动圈式继电器409 Muktiole—reclosing breaker 多次重合闸断路器410 Multi-ended circuit protection 多端线路保护411 Multi-finger contactor 多触点接触器412 Multi-phase compensated impedance relay 多相补偿式阻抗继电器413 Multiple earth 多重接地414 Multi—zone rekay 分段限时继电器415 Mutual—induction 互感416 Mutual—induction of zero sequence 零序互感的影响417 Mutually coupled lines 有互感线路418 Negative direction 反方向419 Negative phase relay 负相位继电器420 Negative sequence impedance 负序阻抗421 Negative-phase sequence impendence 负相序继电器422 Network topology 网络拓朴423 Neutral auto—transformer 中性点接地自耦变压器424 Neutral displacement protection 中性点过电压保护425 Neutral—current transformer 零序电流互感器426 Neutral—point earthing 中性点接地427 No—load release 无跳闸428 Non-linear characteristics 非线性特性429 Non—sinusoidal signal 非正弦信号430 Normal inverse 反时限431 Normally closed contacts 常闭节点432 Normally open contacts 常开节点433 Object—oriented 面向对向434 Off-peak 非峰值的435 Off-position 断开位置436 Offset impedance relay 偏移特性阻抗继电器437 Ohm relay 电阻继电器438 Oil-immersed type reactor 油浸式电抗器439 Open-phase relay 断相继电器440 Operating characteristic 动作特性441 Operating eqution(criterion) 动作方程(判据)442 Operating load 运行负载443 Operating time 动作时间444 Operational(internal)over—voltage 操作(内部)过电压445 Optical link protection 光纤保护446 Option board 选择板447 Optoelectronic coupler 光电耦合器件448 Orthogonal 正交的449 Oscillation 振荡450 Oscillator coil 振荡线圈451 Oscillatory reactivity perturbation 振荡反应性扰动452 Oscillatory surge 振荡冲击453 Out flowing current 外汲电流454 Out going line 引出线455 Out of service 退出运行456 Out of step 失步457 Outlet 出口458 Output(executive) organ 出口(执行)元件459 Over current protection 过电流保护460 Over fluxing ptrtection 过励磁保护461 Over head line 架空线462 Over load 过负荷463 Over reach blocking scheme 超范围闭锁式464 Over voltage protection 过电压保护465 Over voltage relay 过压继电器531466 Over—current relay withunder—voltage supervision 低电压起动的过电流保护467 Over—load relay 过载继电器468 Over-load trip 过载跳闸469 Parallel 并联470 Parallel port 并联出口471 Peak value （交变量的）最大值472 Percentage differential protection 比率差动保护473 Percentage differential relay 比率差动继电器474 Permanent fault 永久性故障475 Permissive under reaching transfertrip scheme 欠范围允许跳闸式476 Permissive underreach protection 允许式欠范围保护477 Phase comparison protection 相位比较保护478 Phase comparison relay 相位比较继电器479 Phase segregated protection 分相保护480 Phase to phase fault 相间故障481 Phase-angle of voltage transformer 电压互感器的相角差482 Phase-shifting algorithm 移相算法483 Pilot protection 高频保护；纵联保护484 Pilot protection using distance relay 距离纵联保护485 Platform 平台486 Pneumatic 气动的487 Pockels effect 波克尔斯效应488 Polar characteristics 极化特性489 Polarized voltage 极化电压490 Pole-pairs 极对数491 Porcelain insulator 瓷绝缘子492 Positive sequence impedance 正序阻抗493 Potential transformer 电压互感器494 Power direction relay 功率方向继电器495 Power factlr relay 功率因数继电器496 Power failure 电源故障497 Power line carrier 电力线载波498 Power line carrier channel 高频通道499 Power line carrier protection 电力线载波保护500 Power relay 功率继电器501 Power rheostat 电力变压器502 Power swing(out of step)blocking 振荡(失步）闭锁503 Power system analysis and computation 电力系统分析与计算504 Power system control 电力系统控制505 Power system oscillation 电力系统振荡506 Power system splitting and reclosing 解列重合闸507 Power system transients 电力系统暂态508 Power—angle 功角509 Power-angle curve 功角特性曲线510 Power-transfer relay 电源切换继电器511 Power—transformer relay 电力传输继电器512 Primary 一次侧的513 Primary protection 主保护514 Private line 专用线路515 Proportional Brake LongitudinalDifferential Protection 比例制动式纵差保护516 Protection against overpressure 超压防护517 Protection against unsymmetrical load 不对称负载保护装置518 Protection criterion 保护判据519 Protection device 保护设备;防护设备520 Protection feature 保护特性521 Protection of generator-transformer set 发电机—-变压器保护522 Protection reactor 保护电抗器523 Protection screen 保护屏524 Protection switch 保护开关525 Protective cap 保护帽526 Protective casing 保护外壳527 Protective cover（protective housing）保护罩528 Protective device(protective gear）保护装置529 Protective earthing 保护接地530 Protective earthing outer insulation 保护接地外绝缘531 Protective equipment 保护设备532 Protective gap 保护间隙533 Protective ground 保护性接地534 Protective link 保护线路535 Protective panel 保护屏柜536 Protective relaying equipment 继电保护装置537 Protective switch 保护开关538 Protective system 保护系统539 Protective transformer 保护变压器540 PT line-break PT断线541 Pulse 脉冲542 Pulse relay（surge relay) 冲击继电器543 Quadrature 正交544 Quadrature axis 交轴545 Quasi—steady state 准稳态546 Rated armature current 额定电枢电流547 Rated burden/Rated load 额定负载548 Rated primary voltage 一次额定电压549 Rated secondary voltage 二次额定电压550 Ratio restrain 比率制动551 Reach（setting)of protection 保护范围（定值)552 Reactance 电抗553 Reactance bond 电抗耦合554 Reactance of armature reaction 电枢反应电抗555 Reactive power cimpensation 无功补偿器556 Reactor grounded neutral system 中性点电抗接地系统557 Receiver machine 收信机558 Reclaim time 复归时间559 Recloser 重合闸560 Rectangular wave 矩形波561 Rectifier bridge 整流桥562 Recursive least square algorihm 最小二乘算法563 Redundancy of relaying system 保护配置的冗余度564 Relay acceleration after auto-reclosing 重合闸后加速保护565 Relay acceleration before auto—reclosing 重合闸前加速保护566 Relay act trip 继电器操作跳闸567 Relay based on incremental quantity 增量（突变量)继电器568 Relay based on transient component 暂态保护569 Relay location 保护安装处570 Relay must—operate value 继电器保证启动值571 Relay overrun 继电器超限运行572 Relay system configuration 保护配置573 Remote backup protection 远后备保护574 Remote controlled 遥控的575 Remote Terminal Unit 远程终端设备576 Remote—control apparatus 远程控制设备577 Reserve bus 备用母线578 Residual current 零序电流支持(0) 中立（0) 反对(0) 单帖管理举报帖子使用道具｜引用｜回复回到顶部美女呀，离线，留言给我吧！admin小大2楼个性首页｜博客| 信息｜搜索| 邮箱| 主页| UC加好友发短信等级：管理员帖子:1714 积分：14741 威望：0 精华：14 注册:2003-12-30 16：34:32 发帖心情Post By：2008-9-3 10：14：51579 Residual current relay 零序电流继电器580 Residual magnetism 剩磁581 Resistance grounded neutral system 中性点接地方式582 Resultant torque 合成转矩583 Returning current of protection device 保护装置返回584 Reverse power flows 功率逆潮流585 Rotor 转子586 Rotor earth-fault protection 转子接地保护587 Rwliability 可靠性588 Sampling and holding 采样保持589 Sampling interruption service program 采样中断服务程序590 Satuation detection 饱和检测591 Saturation curve 饱和曲线592 SCADA 监控与数据采集593 Scalarproduct restraint differentrial relay 标积制动式差动继电器594 Scan 扫描595 Sealed transformer 密封式变压器596 Second harmonic escapement 二次谐波制动597 Secondary circuit 二次回路598 Section selectovity of protection 保护的区选择性599 Sectionalizer 分段断路器600 Security 安全性601 Segregated current differential protection 分相电流差动保护602 Selectivity 选择性603 Self excited 自励604 Self reset 自动复归605 Self—check 自检606 Self—energizing 自激的607 Self-induction 自感608 Self—polarize mho 自极化姆欧(导纳)继电器609 Self—polarizing 电流极化继电器610 Semiconductor diode 半导体二极管611 Semi—orthogonal wavelet 半正交小波612 Sensitive polarized 灵敏极化继电器613 Sensitivity 灵敏性614 Sequence of events recorder 事件顺序记录器615 Sequential tripping 顺序跳闸616 Serial port 串行接口617 Series 串联618 Series excited 串励619 Sesitive relay 灵敏继电器620 Setting calculation 整定计算621 Severe gas protection 重瓦斯保护622 Short circuit calculations 短路计算623 Short-term load forecasting 短期负荷预测624 Shunt 旁路;并联625 Shunt excited 并励626 Shunt running 潜动627 Shutter 挡板628 Sigle—phase transmission line 单相传输线629 Single-chip microcontroller 单片机630 Sinusoidal variations 正弦变量631 Slight gas protection 轻瓦斯保护632 Slow—to release relay 缓放继电器633 Soft strap 软压板634 Solenoid relay 螺管式继电器635 Spark gap 火花间隙636 Speed 速动性637 Splitphase transverse differential protection 裂相横差保护638 Spottily excited 他励639 Star 星形640 Start up（Pick up）起动641 Starting current of protection device 保护装置启动电流642 State estimation 状态估计643 Static distance relay 静态距离继电器644 Static relay 静电继电器645 Stator earth—fault protection 定子接地保护646 Stator ground protection based onzero sequence current 零序电流构成的定子接地保护647 Step—type distance relay 分段距离继电器648 Strap 压板649 Subsystem 子系统650 Successive approximation typw A/D 逐次逼近型A/D651 Superimposed component protection 叠加分量保护652 Surge guard 冲击防护653 Surge impedance 波阻抗654 Surge voltage 冲击电压655 Sustained faults 持续性故障656 Sustained overload 持续657 Switch cabinet 开关柜658 Switch station 开关站659 Switching surge 开关冲击660 Symmetrical 对称的661 Symmetrical comoinents 对称分量662 Synchronization check 同期检查663 Synchronized sampling 采样同步664 Synchronizing by reference parameter vector 参数矢量同步法665 Synchronous condenser 同步调相机666 Synchronous reactance 同步电抗667 Synchronous speed 同步转速668 Tap 分接头669 Telemeter data 遥测数据670 Temperature limiting relay 过热继电器671 Temporary fault 瞬时性故障672 Terminal board 端子排673 Terminal voltage 端电压674 Test—block 试验端子675 Test—plug 试验插头676 The applied voltage 外施电压677 The no-load power factor 空载功率因数678 Thermal protection 过热保护679 Thermostat relay 恒温继电器680 Three phase one shot reclosure 三相一次重合闸681 Three terminal line protection 三端线路保护682 Through—fault 穿越故障683 Thyristor 晶体管684 Tie line 联络线685 Time interval 时间间隔686 Time over—current 时限过电流687 Time pulse relay 定时脉冲继电器688 Time-current characteristic 时间-电流特性689 Time-delay relay 时间继电器690 Time-invariant 不变时的691 Timer relay 延时继电器692 Timing relay(Timed relay）定时继电器693 Topological information 拓朴信息694 Topology analysis 拓朴分析695 Torque-angle 转矩角696 Torsional vibration 扭转振动697 Tower 杆塔698 Transfer of auxiliary supply 后备电源切换699 Transformation matrix 变换矩阵700 Transformer protection schemes 变压器保护配置原则701 Transient analysis 暂态分析702 Transistor(type)relay 晶体管（型）继电器703 Transition impedance 过渡阻抗704 Transmission line malfunction 输电线路异常运行705 Transmitting relay 发送继电器706 Transverse differential protection 横差保护707 Transverse differential protectionfor Generator turn—to—turn faults 发电机横差保护708 Traveling wave 行波709 Traveling wave protection 行波保护710 Traveling wave relay 行波继电器711 Traveling wave signal 行波信号712 Trigger 触发器713 Trip by lical protection 保护跳闸714 Trip relay 跳闸继电器715 Trip switch 跳闸开关716 Tripping battery 跳闸用蓄电池717 Troidal 环形的;曲面；螺旋管形718 Turn to turn gault 匝间短路719 Two star connection scheme 两相星形接线方式720 Two—phase grounding fault 两相接地短路故障721 Two—phase short circuit fault 两相短路故障722 Two—position relay 二位置继电器723 Ultra—high voltage transmission 超高压输电724 Unavailability 不可用率;失效率725 Unbalance current 不平衡电流726 Unblocking signal 解除闭锁信号727 Under power protection 低功率保护728 Under power relay 低功率继电器729 Under-frequency protection 低频保护730 Under—groind cable 地埋电缆731 Under-impedance relay 低阻抗继电器732 Under—load relay 负载不足继电器733 Under-voltage protection 欠压保护734 Under—voltage relay 欠压继电器735 Under-voltage release736 Under—voltage trip 低电压跳闸737 Unit protection 单元式保护738 Vacuum circuit breaker 真空开关739 Vacuum—tube relay 电子管继电器740 Variable bridge principle protection 变电桥保护741 Vibration 振荡742 Voltage balance relay 电压平衡继电器743 Voltage differential relay 电压差动继电器744 Voltage dip 电压下降745 Voltage inception angle 电压初始角746 Voltage instability 电压不稳747 Voltage regulation 电压调节748 Voltage responsive relay 电压响应继电器749 Voltage selection relay 电压选择继电器750 Voltage sensor 电压传感器751 Voltage traveling wave 电压行波752 Voltage waveform destortion 电压波形畸变753 Voltage-controlled over-current relay 电压控制过电流继电器754 Volt-amphere characteristic 伏安特性755 Wave impedance 波阻抗756 Wave propagation velocity 波速757 Waveform 波形758 Waveform identification 波形识别法759 Wavelet transform 小波变换760 Weak power end protection 弱电源端保护761 Winding—to—winding insulation 绕组间的绝缘762 Window function 窗函数763 Zero drift 零点漂移764 Zero mode component of traveling wave 零模行波765 Zero—power-factor 零功率因数766 Zero—sequence current 零序电流767 Zero—sequence current compensation 零序电流补偿768 Zero-sequence current relay 零序电流继电器769 Zero—sequence current transducer 零序电流互感器770 Zero-sequence impedance 零序阻抗771 Zero-sequence protection 零序保护。

2023年高考英语语法重难点复习填空精练15篇附答案阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。

The home crowd erupted when China's Eileen Gu won the Women's Freeski Big Air gold in Beijing.Gu jumped into the top position with herdebut at the Winter Olympics.and a Chinese mother.She grew up in the United States.It wasin the world cup for the sport.Then,she decided to switch from representing themake...Through skiing,I hope to unite people,promote common understanding,create communication and forge friendships阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。

Six weeks before his 97th birthday,Giuseppe Paternòfulfilled the dreambecause his life story speaks of commitment,a theme that has resonated(产生共鸣)as millions of schoolchildren in Italy and elsewhere face extraordinary uncertainty during the coronavirus pandemic.Born in Palermo in 1923,the first of seven children in a“very poorschool.It was only after he retired,in the mid-1980s,that he returned to his books.“His story proves that dreams can come true and that you can remain young—if not in age at least in spirit—if you develop interests.”said RosellaUniversity of Palermo.Italy’s university system is based on a three-yearHe isn’t so sure.“I have to admit that in this moment,I don’tall the attention had been a bit tiring.Still,Mr.Paternòsaid,he阅读下面材料，在空白处填入适当的内容（1个单词）或括号内单词的正确形式。

一类具局部化源的快扩散方程解的熄灭孟繁慧;高文杰【摘要】研究一类具局部化源的快扩散方程解的熄灭性质.通过分析非线性扩散项和非线性源项对解熄灭的影响并借助一些特殊构造的上下解,得到了该问题解的临界熄灭指标.结果表明:当源项指标适当大时,该问题的解对于适当小的初值在有限时刻熄灭;当源项指标适当小时,其最大解不熄灭.【期刊名称】《吉林大学学报（理学版）》【年(卷),期】2013(051)006【总页数】5页(P1041-1045)【关键词】快扩散方程;局部化源;临界熄灭指标【作者】孟繁慧;高文杰【作者单位】长春金融高等专科学校,长春130028;吉林大学数学学院,长春130012【正文语种】中文【中图分类】O175.80 引言考虑如下快扩散方程：解的熄灭性质.其中：0＜m＜1；a，q＞0；Ω是ℝN（N≥1）中的有界光滑区域；x0是Ω中的一个固定点；非负函数u0∈L∞（Ω）.该模型是一个耦合局部化源的快扩散方程，具有较强的物理和生物学背景，可以用来描述具有内部源的流体在多孔介质中的扩散或种群密度的变化规律［1－3］.解的有限时刻熄灭与解的有限时刻爆破相对应，也是发展型方程的一个重要性质.自Kalashnikov［4］通过比较 Cauchy问题：的解及其显式解提出解的有限时刻熄灭概念以来，关于该问题的研究已引起人们广泛关注.目前，发展方程解的熄灭理论已日趋完善［5－12］.特别地，如下形式的快扩散方程：得到了广泛研究，其中0＜m＜1.当f（u）＝auq，a，q＞0时，借助积分估计和Sobolev嵌入定理，李玉祥等［13］证明了：如果q＞m，则对适当小的初值u0，问题（2）的唯一解在有限时刻熄灭；如果q＜m，问题（2）的最大解在Ω内是恒正的；对于临界情形q＝m，问题（2）的解是否熄灭取决于－Δ在Ω上第一特征值的大小.田娅等［14］和尹景学等［15］分别对p－Laplace方程证明了类似的结论.当时，韩玉柱等［16］证明了该问题的临界熄灭指标为q＝m.与具局部源相对应的问题为：当q＝m时，问题（2）的解是否熄灭取决于aμ的大小.这里μ＝∫Ωφ（x）dx，φ（x）是如下线性椭圆方程的唯一正解：基于上述结果，本文研究问题（1）解的临界熄灭指标.1 预备知识当m＞1时，问题（1）是退化的；当0＜m＜1时，问题（1）是奇异的，所以它没有古典解.为了对问题（1）定义恰当的弱解，对任意的0＜T＜∞，记引入如下检验函数类：定义1 如果函数u∈L∞（QT）满足下列条件：1）u（x，0）≤（≥）u0（x），x∈Ω；2）u（x，t）≤（≥）0，（x，t）∈ΓT；3）对任意的t∈（0，T）和任意的ξ∈F，则称函数u是问题（1）在QT上的一个弱下解（弱上解）.如果u既是弱上解、又是弱下解，则称u是问题（1）在QT上的一个弱解.线性椭圆方程解具有相关性质：本文令φ（x）为式（3）的唯一正解，并记问题（1）弱解的局部存在性证明过程是标准的［17］.考虑如下正则化问题：这里选取T＞0适当小，使得对任意的k∈ℕ，问题（4）在QT上存在唯一正解uk（x，t），且‖uk‖L∞（QT）关于k是一致有界的.事实上，对任意的k∈ℕ，下述常微分方程Cauchy问题的解都是问题（4）的一个上解：选取T＞0为问题（5）的最大存在区间即可.此外，由一致抛物型方程的比较原理［18］可知，若k＜l，则1／l≤ul≤uk.由于uk关于k单调递减，故可定义易验证U（x，t）是问题（1）的一个弱解.如果u是问题（1）的任意解，则有下面定义有界函数Φk和Fk，使其满足进一步可得用类似文献［17］的方法选取一个恰当的检验函数ξ并借助Gronwall不等式可得u≤uk，从而u（x，t）≤U（x，t）.如果v是问题（1）的一个下解，则同理可得v≤U.于是，U（x，t）是问题（1）的最大解，且满足下解比较原理.类似上述过程可得：命题1 假设v和u分别是问题（1）在QT上的非负上、下解，且存在δ＞0，使得u≥δ，则u≤v于QT.2 主要结果定理1 如果q＞m，则当初值u0适当小时，问题（1）的解在有限时刻熄灭；如果q＝m且aμ＜1，则问题（1）的解对任意有界非负初值都在有限时刻熄灭.证明：首先证明q＝m且aμ＜1的情形.通过构造一个在有限时刻熄灭的上解完成证明.设φ1（x）是问题的唯一正解，这里区域Ω1满足Ω⊂Ω1.如果记则由线性椭圆方程的强极值原理可知μ1＞μ，δ＞0.其中μ＝∫Ωφ（x）dx，φ（x）是问题（3）的唯一正解.注意到方程（6）的解对区域Ω1有连续依赖性及假设aμ＜1，从而可以选取适当的区域Ω1⊃Ω，使得aμ1＜1.设g（t）是下述常微分方程初值问题的唯一解：这里常数A＞0满足对任意的由0＜m＜1可知，g（t）是单调不增的，且在时刻熄灭.定义易见v（x，t）也在T0 时刻熄灭.直接验证可知，v（x，t）是问题（1）的一个上解.事实上，v（x，t）（在弱的意义下）满足：此外，对任意给定的0＜T＜T0，存在正常数C1，C2，使得于是在×［0，T］上对v（x，t）和u（x，t）应用命题1可得u（x，t）≤v（x，t）.由T＜T0的任意性和v（x，T0）＝0可知u（x，T0）＝0.定义（x，t）＝u（x，t＋T0），则（x，t）是问题（1）的满足初值条件（x，0）＝0的解.同理对任意的A＞0，（x，t）≤v（x，t）.由v（x，t）的熄灭时间T0与A的关系可知，对任意的t＞0，有（x，t）＝0，即对任意的t≥T0，u（x，t）＝0.表明u（x，t）在T0 时刻熄灭.下面考虑q＞m的情形.令易验证，对于充分小的正常数k，如下关系式成立：固定满足上述条件的常数k可知，当初值u0（x）适当小使得u0（x）≤v（x）成立时，v（x）即为问题（1）的一个上解.此外，它还是有正下界的.由命题1可得从而u（x，t）是下述问题的弱下解：其中注意到a1 和具有正相关性，故当u0 充分小使得a1μ＜1时，w（x，t）在有限时刻熄灭，从而u（x，t）也在有限时刻熄灭.证毕.定理2 如果q＜m或q＝m且aμ＞1，则对任意非负初值u0（x），问题（1）的最大解U（x，t）是不熄灭的.证明：由于问题（1）的最大解U（x，t）满足下解比较原理，所以为证明定理的结论，只需构造一个不熄灭的下解即可.设v（x，t）＝g（t）φ1／m（x），其中φ（x）是问题（3）的唯一正解.如果g（t）满足如下常微分方程：则g（t）是单调不减且上方有界的.此外，容易验证v（x，t）是问题（1）当q＜m时的一个不熄灭下解.事实上，当x∈Ω时，v（x，0）＝0≤u0（x）；当x∈∂Ω时，v（x，t）＝0，且v（x，t）（在弱的意义下）满足：如果q＝m且aμ＞1，选取g（t）使其满足：同理可验证v（x，t）是问题（1）的一个不熄灭下解.于是U（x，t）不可能在任何有限时刻熄灭.证毕.注1 当q＝m且aμ＝1时，易验证对任意的k＞0，kφ1／m（x）是问题（1）的一个稳态解.从而对任意光滑的正初值u0（x），问题（1）的最大解U（x，t）是不熄灭的.参考文献【相关文献】［1］Vazquez J L.The Porous Medium Equation［M］.Oxford：Clarendon Press，2007. ［2］CHEN You－peng，XIE Chun－hong.Blow－up for a Porous Medium Equation with a Localized Source［J］.Appl Math Comput，2004，159（1）：79－93.［3］CHEN You－peng，LIU Qi－lin，GAO Hong－jun.Boundedness of Global Solutions of a Porous Medium Equation with a Localized Source［J］.Non Anal：Theory，Methods ＆Applications，2006，64（10）：2168－2182.［4］Kalashnikov A S.The Nature of the Propagation of Perturbations in Problems of Non－linear Heat Conduction with Absorption［J］.USSR Comp Math Math Phys，1974，14（4）：891－905.［5］Diaz G，Diaz I.Finite Extinction Time for a Class of Non－linear Parabolic Equations ［J］.Comm Part Differ Equations，1979，4（11）：1213－1231.［6］Lair A V，Oxley M E.Extinction in Finite Time for a Nonlinear Absorption－Diffusion Equation［J］.J Math Anal Appl，1994，182（3）：857－866.［7］Galaktionov V A，Vazquez J L.Asymptotic Behavior of Nonlinear Parabolic Equations with Critical Exponents.A Dynamical System Approach［J］.J Funct Anal，1991，100（2）：435－462.［8］Galaktionov V A，Vazquez J L.Extinction for a Quasilinear Heat Equation with AbsorptionⅠ.Technique of Intersection Comparison［J］.Comm Part Differ Equations，1994，19（7／8）：1075－1106.［9］Galaktionov V A，Vazquez J L.Extinction for a Quasilinear Heat Equation with AbsorptionⅡ.A Dynamical System Approach［J］.Comm Part Differ Equations，1994，19（7／8）：1107－1137.［10］Ferreira R，Vazquez J L.Extinction Behavior for Fast Diffusion Equations with Absorption ［J］.Non Anal：Theory，Methods ＆ Applications，2001，43（8）：943－985.［11］Friedman A，Herrero M A.Extinction Properties of Semilinear Heat Equations with Strong Absorption ［J］.J Math Anal Appl，1987，124（2）：530－546.［12］Herrero M A，Velazquezj J J L.Approaching an Extinction Point in One－Dimensional Semilinear Heat Equations with Strong Absorptions［J］.J Math Anal Appl，1992，170（2）：353－381.［13］LI Yu－xiang，WU Ji－chun.Extinction for Fast Diffusion Equations with Nonlinear Sources［J］.Electron J Differ Equations，2005，2005（23）：1－7.［14］TIAN Ya，MU Chun－lai.Extinction and Non－extinction for a p－Laplacian Equation with Nonlinear Source ［J］.Non Anal：Theory，Methods ＆ Applications，2008，69（8）：2422－2431.［15］YIN Jing－xue，JIN Chun－hua.Critical Extinction and Blow－up Exponents for Fast Diffusive p－Laplacian with Sources［J］.Math Method Appl Sci，2007，30（10）：1147－1167.［16］HAN Yu－zhu，GAO Wen－jie.Extinction for a Fast Diffusion Equation with a Nonlinear Nonlocal Source ［J］.Arch Math，2011，97（4）：353－363.［17］Anderson J R.Local Existence and Uniqueness of Solutions of Degenerate Parabolic Equations ［J］.Commun Partial Differential Equations，1991，16（1）：105－143. ［18］Protter M H，Weinberger H F.Maximum Principle in Differential Equations ［M］.Englewood Cliffs：Prentice－Hall，1967.。

专业英语1psychology n.心理学mind n.心理；心灵；精神 soul n.灵魂behaviour n.行为 The scientific study of behaviour and mental processes 行为与心理过程的科学研究psychologist n.心理学家philosophy n.哲学 philosopher n.哲学家Empiricism n.经验主义，源于英国哲学家洛克，认为知识源于后天学习经验。

行为主义坚持这一观点，强调必须通过观察与实验来研究客观事实为对象的心理现象，例如外显行为。

Positivism n.实证主义，源于法国哲学家孔德，认为科学只研究可以观察到或经验到的事实，实证即只承认能确证的事实。

biology n.生物学 evolution n.进化 genetics n.遗传学physiology 生理学endocrine n.内分泌；激素physics n.物理学physicist n.物理学家 psychophysics n.心理物理学separate scientific discipline 独立的科学学科Principles of psychology 心理学原理structuralism 结构主义 conscious a.有意识的 introspection n.内省image n.意象；心象 sensation n.感觉，知觉feeling n.触觉，知觉，感觉；感情，情感 functionalism n.功能主义thought n.思想 psychoanalysis n.心理分析 therapy n.治疗，疗法The interpretation of dreams 梦的解析 unconscious mind 无（潜）意识心理Behaviourism行为主义 experimental psychology 实验心理学cognitive a.认知的 humanistic a.人本主义的cognitive psychology 认知心理学专业英语2variables 变量 aggression 攻击；侵犯 intelligence 智力operationalisation 操作化abstract concepts 抽象概念observable behaviour 可观察行为puzzle 测验智力的问题（或玩具）；难题reification （抽象概念等）具体化；观念与现象混淆 observations 观察法case studies 个案研究法 surveys 调查法 correlations 相关性experiments 实验法 independent variable 自变量dependent variable 因变量extraneous variables 外扰变量；无关变量controls 控制 confounding variables 混杂变量random 随机 constant 恒定 hypotheses 假设2-tailed hypotheses 双极假设 1-tailed hypotheses 单极假设operationalised variables 操作性的变量 statistically singnificant 统计学意义上的显着null hypotheses 零假设 significant effect 显着性效果manipulation of the independent variable 自变量的操纵laboratory 实验室 deliberately manipulates 仔细操纵strict control 严格控制 subject 被试natural environment 自然环境 quasi experiment 准实验专业英语3perception 知觉 sense 感觉；感官 visual perception 视觉，视知觉two-dimensional 二维的 retina 视网膜 three-dimensional 三维的viewpoint 观察点，注视点 shape constancy 形状恒常性size constancy 大小恒常性 luminescence 发光brightness constancy 明度恒常性 luminescence 发光brightness constancy 明度恒常性 illusions 错觉Necker cube 尼克尔立方体 Gestalt 格式塔emergent properties 突变特性 phi phenomenon 似动现象Law of Pragnanz 完形倾向性定律 proximity 邻近性similarity 相似性 continuity 连续性closure 闭合 figure-ground 图形-背景common fate 共同命运，以相同方向运动的物体会被组织在一起专业英语4attention 注意 sensory stimuli 感觉刺激focused or selective attention 集中或选择注意divided attention 分配注意 vision 视觉 hearing 听觉visual field 视野 target 目标；靶专业英语5encode 编码memory 记忆photon 光子；见光度（等于通过一平方厘米大的瞳孔看到每平方米一支蜡烛的照明度）represent 描述；代表；象征 imagery memory 形象记忆representation 表征 iconic (visual) 映象的；形象的echoic (auditory) 回声的；声象的 recall 回忆 tune 声调working memory 工作记忆 the central executive 中央执行器Visuospatial scratchpad 视觉空间模板 phonological loop 语音回路photographic (eidetic) memory 映象记忆 procedural memory 程序记忆implicit memory 内隐记忆enactive mode 动作性模式，指人们用“动作”来表达他们关于世界的知识和经验。

2025年北师大版英语高考复习试题与参考答案一、听力第一节（本大题有5小题，每小题1.5分，共7.5分）1、Listen to the following dialogue between two students, and answer the question.Student A: Hey, are you planning to follow the exam schedule strictly? Student B: Yeah, I always try to stick to a routine. How about you?Student A: Well, I like to mix it up a bit. It keeps me motivated.Question: What does Student A prefer when it comes to following an exam schedule?A. To follow the routine strictly.B. To mix up the schedule to stay motivated.C. To follow the schedule only when it’s convenient.D. To avoid any schedule altogether.Answer: BExplanation: Student A indicates that they like to mix up the schedule to stay motivated, which is equivalent to choice B.2、 Listen to the following conversation about a school trip, and complete the following sentence with the correct information.Teacher: Ok, everyone, we’re going to have a field trip next week. It’s a science-themed trip to the museum downtown.Student A: That sounds amazing! What are we going to learn there, though?Teacher: Well, you’ll get a behind-the-scenes look at how exhibits are put together, and you’ll interact with some of the curators. Plus, there are interactive displays where you can try out different experiments.Question: What will the students be able to do during the trip to the museum?A. Simply observe the exhibits without participating.B. Work with the curators to put together new exhibits.C. Participate in interactive experiments and discussions.D. Finish the field trip without visiting the museum.Answer: CExplanation: The teacher mentions that the students will be able to participate in interactive experiments and discussions, which corresponds to choice C.3.What does the man suggest doing?A) Having a picnic.B) Going to the cinema.C) Visiting the museum.D) Playing tennis.Answer: A) Having a picnic.Explanation: The woman mentions that it’s a beautiful day and asks the man what he thinks they should do. The man responds by suggesting they take advantage of the weather and have a picnic in the park. Therefore, the correct answer isA) Having a picnic.4.Where are the speakers most likely?A) At home.B) In a restaurant.C) On a bus.D) In a bookstore.Answer: B) In a restaurant.Explanation: The dialogue involves one speaker asking for recommendations on dishes and commenting on the menu, while the other speaker provides suggestions and describes the specials. This context strongly suggests that the conversation is taking place in a restaurant, making B) In a restaurant the correct choice.5、 Listening Section AQuestion: How is the woman going to the airport?A) By bus.B) By taxi.C) By subway.Answer: BExplanation:In the recording, the man asks, “Are you going to the airport by bus or by taxi?” The woman replies, “I decide to take a taxi because it will be faster.” Therefore, the correct answer is B) By taxi.解析：录音中，男士问：“你要去机场是乘公交还是打车？”女士回答：“我决定打车去，因为会更快。

TPO 07 Paragraph 11．The wordin thepassage is closest in meaning to○achievement○requirement○purpose○feature2．Which of the following is NOT mentioned in paragraph 1 as a change that occurred in the fauna of the Mediterranean?○Most invertebrate species disappeared during a wave ofextinctions.○A few hardy species wiped out many of the Mediterranean’sinvertebrates.○Some invertebrates migrated to Atlantic Ocean.○New species of fauna populated the Mediterranean whenThe Geologic History ofthe MediterraneanIn 1970 geologists Kenneth J. Hsu and William B.F. Ryan were collecting research data while aboard the oceanographicresearch vessel Glomar Challenger. An of this particular cruise was to investigate the floor of the Mediterranean and to resolve questions about its geologic history. One question was related to evidence that the invertebrate fauna (animals without spines) of the Mediterranean had changed abruptly about 6 million years ago. Most of the older organisms were nearly wiped out, although a few hardy species survived. A few managed to migrate into the Atlantic. Somewhat later, the1the old migrants returned.Paragraph 33．What does the author imply by○The most obvious explanation for the origin of the pebbles was not migrants returned, bringing new species with them. Why did the near extinction and migrations occur?■Another task for the Glomar Challenge r’s scientists was to try to determine the origin of the domelike masses buried deep beneath the Mediterranean seafloor. ■These structures had been detected years earlier by echo-sounding instruments, but they had never been penetrated in the course of dri lling. ■Were they salt domes such as are common along the United States Gulf Coast, and if so, why should there have been so much solid crystalline salt beneath the floor of the Mediterranean? ■With question such as these clearly before them, the scientists2supported by the evidence.○The geologists did not find as many pebbles as they expected.○The geologists were looking for a particular kind of pebble.○The different pebbles could not have come from only one source.4．Which of the following can be inferred from paragraph 3 about the solid gypsum layer?○It did not contain any marine fossil.○It had formed in open-ocean conditions.○It had once been soft, deep-sea mud.○It contained sediment from nearby deserts.5. Select the TWO answer choice from paragraph 3 that identify materials discovered in the deepest part of the Mediterranean basin. To receive credit aboard the Glomar Challenger processed to the Mediterranean to search for the answers. On August 23, 1970, they recovered a sample. The sample consisted of pebbles of gypsum and fragments of volcanicIn the days following, samples of solid gypsum were repeatedly brought on deck as drilling operations penetrated the seafloor. Furthermore, the gypsum was found to possess peculiarities of composition and structure that suggested it had formed on desert flats. Sediment above and below the gypsum layer contained tiny marine fossils, indicating open-ocean conditions. As they drilled into the central and deepest part of the Mediterranean basin, the3you must select TWO answers.○Volcanic rock fragments.○This silt layers○Soft, deep-sea mud○Crystalline salt6. What is the main purpose of paragraph 3?○To describe the physical evidence collected by Hsu and Ryan.○To explain why some of the questions posed earlier in the passage could not be answered by the findings of the Glomar Challenger.○To evaluate techniques used by Hsu and Ryan to explore the sea floor.○To describe the most difficult problems faced by the GlomarChallenger expedition.Paragraph 47. According to paragraph 4, which of the following was responsible for the evaporation of the Mediterranean’s scientists took solid, shiny, crystalline salt from the core barrel. Interbedded with the salt were thin layers of what appeared to be windblown silt.The time had come to formulate a hypothesis. The4waters?○The movements of Earth’s crust○The accumulation of sediment layers○Changes in the water level of the Atlantic Ocean○Changes in Earth’s temperature8. The word “scores” in the passage is closest in meaning to○members○large numbers○populations○different types9. According to paragraph 4, what caused most invertebrate species in the Mediterranean to become extinct?○The evaporation of chemicals necessary for their survival○Crustal movements that connected the Mediterranean to the investigators theorized that about 20 million years ago, the Mediterranean was a broad seaway linked to the Atlantic by two narrow straits. Crustal movements closed the straits, and the landlocked Mediterranean began to evaporate. Increasing salinity caused by the evaporation resulted in the extermination ofof invertebrate species. Only a few organisms especially tolerant of very salty conditions remained. As evaporation continued, the remaining brine (salt water) became so dense that the calcium sulfate of the hard layer was precipitated. In the central deeper part of the basin, the last of the brine evaporated to precipitate more soluble sodium chloride (salt). Later, under the weight of overlying sediments, this salt flowed plastically upward to5saltier Atlantic○The migration of new species through the narrow straits○Their inability to tolerate the increasing salt content of theMediterranean10. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.○The strait of Gibraltar reopened when the Mediterranean and the Atlantic became connected and the cascades of water from one sea to the other caused crustal adjustments and faulting.○The Mediterranean was dramatically refilled by water from the Atlantic when crustal adjustments and faulting opened the Strait of Gibraltar, the place where the two seas are joined.○The cascades of water from the form salt domes. Before this happened, however, the Mediterranean was a vast desert 3,000 meters deep. Then, about 5.5 million years ago came the deluge.tore into the hardened salt flats, broke them up, and ground them into the pebbles observed in the first sample taken by the Challenger. As the basin was refilled, normal marine organisms returned. Soon layer of oceanic ooze began to accumulate above the old hard layer.The salt and gypsum, the faunal changes, and the unusual gravel provided abundant6Atlantic to the Mediterranean were not as spectacular as the crustal adjustments and faulting that occurred when the Strait of Gibraltar was connected to those seas.○As a result of crustal adjustments and faulting and the creation of the Strait of Gibraltar, the Atlantic and Mediterranean were connected and became a single sea with spectacular cascades of water between them.11. The word “Turbulent” in the passage is closest in meaning to○fresh○deep○violent○temperateParagraph 212. Look at the four squares ■ that indicate where the following sentence could be added to the passage.Thus, scientists had information about the shape of the domes but not evidence that the Mediterranean was once a desert.gypsum: a mineral made of calcium sulfate and water7about their chemical composition and origin.Where would the sentence best fit?13．An expedition to the Mediterranean answered some long-standing questions about the ocean’s history.●●●Answer choices1. The Glomar Challenger expedition investigated changes in invertebrate fauna and some unusual geologic features.2. Researchers collected fossils to determine which new species migrated from the Atlantic with older species.3. Scientists aboard the Glomar Challenger were the first to discover the existence of domelike masses underneath the seafloor.4. Samples recovered from the■Another task for the Glomar Challenger’s scientists was to try to determine the origin of the domelike masses buried deep beneath the Mediterranean seafloor. ■These structures had been detected years earlier by echo-sounding instruments, but they had never been penetrated in the course of drilling. ■Were they salt domes such as are common along the United States Gulf Coast, and if so, why should there have been so much solid crystalline salt beneath the floor of the Mediterranean? ■8旗开得胜expedition revealed importantdifferences in chemical composition andfossil distribution among the sedimentlayers.5. Evidence collected by the GlomarChallenger supports geologists' beliefsthat the Mediterranean had evaporatedand become a desert, before it refilledwith water.6. Mediterranean salt domes formedafter crustal movements opened thestraits between the Mediterranean andthe Atlantic, and the Mediterraneanrefilled with water.9旗开得胜10Paragraph 11. Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.○The regularity and power of stone walls inspired Romans attempting to unify the parts of their realm.○Although the Romans used different types of designs when building their walls, they used regular controls to maintain their realm.○Several types of control united the Roman realm, just as design and cement held Roman walls together.○Romans built walls to unite the various parts of their realm into a single entity, which was controlled by powerful laws.2. According to paragraph 1, all of the following are controls that held together the roman world EXCEPTAncient Rome and GreeceThere is a quality of cohesiveness about the Roman world that applied neither to Greece nor perhaps to any other civilization, ancient or modern. Like the stone of Roman wall, which were held together both by the regularity of the design and by that peculiarly powerful Roman cement, so the various parts of the Roman realm were bonded into a massive, monolithic entity by physical, organizational, and psychological controls. The physical bonds included the network of military garrisons, which were stationed in every province, and the network of stone-built roads that linked the provinces with Rome. The organizational bonds were based on the common principles of law and administration and on the universal army of officials who enforced common standards of conduct. The psychological controls were built on fear and punishment —on the absolute certainty○administrative and legal systems○the presence of the military○a common language○transportation networksParagraph 23.The phrase “obsession with” in the passage is closest in meaning to○thinking about○fixation on○interest in○attitude toward4.According to paragraph 2, which of the following was NOT characteristic of Rome’s early development?○Expansion by sea invasion○T erritorial expansion○Expansion from one original settlement ○Expansion through invading armies5.Why does the author mention “Alexander the Great” in the passage?○T o acknowledge that Greek civilization that anyone or anything that threatened the authority of Rome would be utterly destroyed.The source of Roman obsession with unity and cohesion may well have lain in the pattern of Rome’s early development. Whereas Greece had grown from scores of scattered cities, Rome grew from one single organism. While the Greek world had expanded along the Mediterranean seas lanes, the Roman world was assembled by territorial conquest. Of course, the contrast is not quite so stark: in Alexander the Great the Greeks had found the greatest territorial conqueror of all time; and the Romans, once they moved outside Italy, did not fail to learn the lessons of sea power. Yet the essential difference is undeniable. The Key to the Greek world lay in its high-11also expanded by land conquest○T o comp are Greek leaders to Roman leaders○T o give an example of Greek leader whom Romans studied○T o indicate the superior organization of the Greek militaryParagraph 36.is closest in meaning to○accepted○combined○introduced○encouraged7.Paragraph 3 suggests which of thefollowing about the people of Latium?○Their economy was based on trade relations with other settlements.○They held different values than the people of Rome.○Agriculture played a significant r ole in the society. powered ships; the key to Roman power lay in its marching legions. The Greeks were wedded to the sea; the Romans, to the land. The Greek was a sailor at heart; the Roman, a landsman.Certainly, in trying to explain the Roman phenomenon, one would have to place great emphasis on this almost instinct for the territorial imperative. Roman priorities lay in the organization, exploitation, and defense of their territory. In all probability it was the fertile plain of Latium, where the Latins who founded Rome originated, that created the habits and skills of landed settlement, landed property, landed economy, landed administration, and a12○They possessed unusual knowledge of animal instinctsParagraph 48.Paragraph 4 indicates that somehistorians admire Roman civilization because of○the diversity of cultures within Roman society○its strength○its innovative nature○the large body of literature that it developed9.In paragraph 4, the author develops adescription of Roman civilization by○comparing the opinions of Roman intellectuals to Greek intellectuals○identifying which characteristics of roman civilization were copied from Greece○explaining how the differences between Roman and Greece developed as time passed○contrasting characteristics of Roman land-based society. From this arose the Roman genius for military organization and orderly government. In turn, a deep attachment to the land, and to the stability which rural life engenders,the Roman virtues: gravitas, a sense of responsibility, peitas, a sense of devotion to family and country, and iustitia, a sense of the natural order.Modern attitudes to Roman civilization range from the infinitely impressed to the thorough disgusted. ■As always, there are the power worshippers, especially among historians, who are predisposed to admire whatever is strong, who feel more attracted to the might of Rome than to the subtlety of Greece. ■At the same time, there is a solid body of opinion that dislikes Rome. ■For many, Rome is at best the imitator and the continuator of Greece on a larger scale. ■Greek civilization had quality; Rome,13civilization with characteristics of Greek civilization10.According to paragraph 4, intellectual Romans such as Horace held which of the following opinions about their civilization?○Ancient works of Greece held little value in the Roman world.○The Greek civilization had been surpassed by the Romans.○Roman civilization produced little that was original or memorable.○Romans valued certain types of innovations that had been ignored by ancient Greeks.Paragraph 5mere quantity. Greece was the inventor; Rome, the research and development division. Such indeed was the opinion of some of the more intellectual Romans.” had the Greeks held novelty in such disdain as we,” asked Ho race in his Epistle, “what work of ancient date would now exist?”Rome’s debt to Greece was enormous. The Romans adopted Greek14Paragraph 611.The wordin thepassage is closest in meaning to○abilities○areas○combinations○models12.Which of the following statements about leading Roman soldiers and statesmen is supported by paragraphs 5 and 6?○They could read and write the Greek language.○They frequently wrote poetry and plays.○They focused their writing on military matters.○They wrote according to the philosophical laws of the Greeks.Paragraph 413.Look at the four squares ■ that religion and moral philosophy. In literature, Greek writers were consciously used as models by their Latin successors. It was absolutely accepted that an educated Roman should be fluent in Greek. In speculative philosophy and the sciences, the Romans made virtually no advance on early achievements.Yet it would be wrong to suggest that Rome was somehow a junior partner in Greco-Roman civilization. The Roman genius was projected into newespecially into those of law, military organization, administration, and engineering. Moreover, the tensions that arose within the Roman state produced literary and artistic sensibilities of the highest order. It was no accident that many leading Roman soldiers and statesmen were writers of high caliber.15indicate where the following sentence could be added to the passage.They esteem symbols of Roman power, such as the massive Colosseum. Where would the sentence best fit?14.The Roman world drew its strength from several important sources●●●Answer choices1. Numerous controls imposed by Roman rulers held its territory together.2. The Roman military was organized differently from older military organizations.3. Romans valued sea power as did the Latins, the original inhabitants of Rome.4. Roman values were rooted in a strong attachment to the land and the stability of rural life.5. Rome combined aspects of ancient Greek civilization with its own contributions in new areas. civilization range from the infinitely impressed to the thorough disgusted. ■As always, there are the power worshippers, especially among historians, who are predisposed to admire whatever is strong, who feel more attracted to the might of Rome than to the subtlety of Greece. ■At the same time, there is a solid body of opinion that dislikes Rome. ■For many, Rome is at best the imitator and the continuator of Greece on a larger scale. ■Greek civilization had quality; Rome, mere quantity. Greece was the inventor; Rome, the research and development division. Such indeed was the opinion of some of the more intellectual Romans.” had the Greeks held novelty in such166. Educated Romans modeled their own literature and philosophy on the ancient Greeks disdain as we,” asked Horace in his Epistle, “what work of ancient date wo uld now exist?”17Paragraph 11.The wordin thepassage is closest in meaning to○emerged○was understood○spread○developed2.According to paragraph 1, why do researchers doubt that agriculture developed independently in Africa?○African lakes and rivers already provided enough food for people to survive without agriculture.○The earliest examples of cultivated plants discovered in Africa are native to Asia.○Africa’s native plants are very difficult to domesticate.○African co mmunities were not large enough to support agriculture.无老师网站:ibtsat3.In paragraph 1, what does theAgriculture, Iron, andthe Bantu PeoplesThere is evidence of agriculture in Africa prior to 3000 B.C. It may have developed independently, but many scholars believe that the spread of agriculture and iron throughout Africa linked it to the major centers of the Near East and Mediterranean world. The drying up of what is now the Sahara desert had pushed many peoples to the south into sub-Sahara Africa. These peoples settled at first in scattered hunting-and-gathering bands, although in some places near lakes and rivers, people who fished, with a more secure food supply, lived in larger population concentrations. Agriculture seems to have reached these people from the Near East, since the first domesticated crops were millets and sorghums whose18author imply about changes in the African environment during this time period?○The climate was becoming milder, allowing for a greater variety of crops to be grown.○Although periods of drying forced people south, they returned once their food supply was secure.○Population growth along rivers and lakes was dramatically decreasing the availability of fish.○A region that had once supported many people was becoming a desert where few could surviveParagraph 24.According to paragraph 2,camels were important because they ○were the first domesticated animal to be introduced to Africa○allowed the people of the West African savannahs to carve out large empires origins are not African but west Asian. Once the idea of plantingtheir own crops, such as certain varieties of rice, and they demonstrated a continued receptiveness to new imports. The proposed areas of the domestication of African crops lie in a band that extends from Ethiopia across southern Sudan to West Africa. Subsequently, other crops, such as bananas, were introduced from Southeast Asia.Livestock also came from outside Africa. Cattle were introduced from Asia, as probably were domestic sheep and goats.19○helped African peoples defend themselves against Egyptian invaders○made it cheaper and easier to cross the Sahara5.According to paragraph 2, which of the following were subjects of rock paintings in the Sahara?○Horses and chariots○Sheep and goats○Hyksos invaders from Egypt○Camels and cattleParagraph 36.What function does paragraph 3 serve in the organization of the passage as a whole○It contrasts the development of iron technology in West Asia and West Africa. Horses were apparently introduced by the Hyksos invaders of Egypt (1780-1560 B.C.) and then spread across the Sudan to West Africa. Rock paintings in the Sahara indicate that horses and chariots were used to traverse the desert and that by 300-200 B.C., there were trade routes across the Sahara. Horses were adopted by peoples of the West African savannah, and later their powerful cavalry forces allowed them to carve out large empires. Finally, the camel was introduced around the first century A.D. This was an important innovation, because the camel’s abilities to thrive in harsh desert conditions and to carry large loads cheaply made it an effective and efficient means of transportation. The camel transformed the desert from a barrier into a still difficult, but more20○It discusses a non-agricultural contribution to Africa from Asia.○It introduces evidence that a knowledge of copper working reached Africa and Europe at the same time.○It compares the rates at which iron technology developed in different parts of Africa.Paragraph 47.The wordin thepassage is closest in meaning to ○fascinating○far-reaching○necessary○temporary8.Theword in thepassage is closest in meaning to ○military○physical○ceremonial accessible, route of trade and communication.Iron came from West Asia, although its routes of diffusion were somewhat different than those of agriculture. Most of Africa presents a curious case in which societies moved directly from a technology of stone to iron without passing through the intermediate stage of copper or bronze metallurgy, although some early copper-working sites have been found in West Africa. Knowledge of iron making penetrated into the forest and savannahs of West Africa at roughly the same time that iron making was reaching Europe. Evidence of iron making has been found in Nigeria, Ghana, and Mali.This technological shift causein the complexity of African societies. Iron21○permanent9.According to paragraph 4, all of the following were social effects of the new metal technology in Africa EXCEPT: ○Access to metal tools and weapons created greater social equality.○Metal weapons increased the power of warriors.○Iron tools helped increase the food supply.○T echnical knowl edge gave religious power to its holders.Paragraph 510.Which of the sentences below best expresses the essential information in the highlighted sentence in the passage? Incorrect choices change the meaning in important ways or leave out essential information.○While American iron makers developed the latest furnaces, African iron makers continued using earlier represented power. In West Africa the blacksmith who made tools and functions. Iron hoes, which made the land more productive, and iron weapons, which made the warrior more powerful, had symbolic meaning in a number of West Africa societies. Those who knew the secrets of making ironand sometimes political power.22techniques.○Africans produced iron much earlier than Americans, inventing technologically sophisticated heating systems.○Iron making developed earlier in Africa than in the Americas because of the ready availability of carbon and iron ore.○Both Africa and the Americas developed the capacity for making iron early, but African metallurgy developed at a slower rate.Paragraph 611.The wordin thepassage is closest in meaning to○afraid of○displaced by○running away from○responding to12.Paragraph 6 mentions all of the following as possiblecauses of theright into the Iron Age, taking the basic technology and adapting it to local; conditions and resources.The diffusion of agriculture and later of iron was accompanied by a great movement of people23“Bantu explosion” EXCEPT○superior weapons○better hunting skills○peaceful migra tion○increased populationParagraph 613.Look at the four squares ■ that indicate where the following sentence could be added to the passage.T hese people had a significant linguistic impact on the continent as well.Where would the sentence best fit?14.Agriculture and iron working probably spread to Africa from neighboring regions.●●●Answer choices who may have carried these innovations. These people probably originated in eastern Nigeria. ■Their migration may have been set in motion by an increase in population caused by a movement ofthe desiccation, or drying up, of the Sahara. ■They spoke a language, prior-Bantu (“Bantu” means “the people”), which is the parent tongue of a language of a large number of Bantu languages still spoken throughout sub-Sahara Africa. Why and how these people spread out into central and southern Africa remains a mystery, but archaeologists believe that their iron weapons allowed them to conquer their hunting-gathering opponents, who still used stone implements. ■Still, the process is uncertain, and peaceful migration—or simply rapid241 .Once Africans developed their own crops, they no longer borrowed from other regions.2. The harshness of the African climate meant that agriculture could not develop until after the introduction of iron tools.3. The use of livestock improved transportation and trade and allowed for new forms of political control.4. As the Sahara expanded, the camel gained in importance, eventually coming to have religious significance.5. The spread of iron working had far-reaching effects on social, economic, and political organization in Africa.6. Today's Bantu-speaking peoples are descended from a technologically advanced people who spread throughout Africa. demographic growth—may have also caused the Bantu explosion. ■25。

2021年托福阅读PASSAGE 77试题及答案PASSAGE 77It is estimated that over 99 percent of all species that ever existed have become extinct. What causes extinction? When a species is no longer adapted to a changed environment, it may perish. The exact causes of a species' death vary from situation to situation. Rapid ecological change may render an environment hostile to a species. For example, temperatures may change and a species may not be able to adapt. Food resources may be affected by environmental changes, which will then cause problems for a species requiring these resources. Other species may become better adapted to an environment, resulting in competition and, ultimately, in the death of a species. The fossil record reveals that extinction has occurred throughout the history of Earth. Recent analyses have also revealed that on some occasions many species became extinct at the same time—a mass extinction. One of the best-known examples of mass extinction occurred 65 million years ago with the demise of dinosaurs and many other forms of life. Perhaps the largest mass extinction was the one that occurred 225 million years ago, when approximately 95 percent of all species died, mass extinctions can be caused by a relatively rapid change in the environment and can be worsened by the close interrelationship of many species. If, for example, something were to happen to destroy much of the plankton in the oceans, then the oxygen content of Earth would drop, affection even organisms not living in the oceans. Such a change would probably lead to a mass extinction.One interesting, and controversial, finding is that extinctions during the past 250 million years have tended to be more intense every 26 million years. This periodic extinction might be due to intersection of the Earth's orbit with a cloud of comets, but this theory is purely speculative. Some researchers have also speculated that extinction may often be random. That is, certain species may be eliminated and others may survive for no particular reason. A species' survival may have nothing to do with its ability or inability to adapt. If so, some of evolutionary history may reflect a sequence of essentially random events.1. The word "it" in line 3 refers to(A) environment(B) species(C) extinction(D) 99 percent2. The word "ultimately" in line 8 is closest in meaning to(A) exceptionally(B) dramatically(C) eventually(D) unfortunately3. What does the author say in paragraph 1 regarding most species in Earth's history(A) They have remained basically unchanged from their original forms.(B) They have been able to adapt to ecological changes.(C) They have caused rapid change in the environment.(D) They are no longer in existence.4. Which of the following is NOT mentioned in paragraph 1 as resulting from rapid ecological change?(A) Temperature changes(B) Availability of food resources(C) Introduction of new species(D) Competition among species5. The word "demise" in line 12 is closest in meaning to(A) change(B) recovery(C) help(D) death6. Why is "plankton" mentioned in line 17?(A) To demonstrate the interdependence of different species.(B) To emphasize the importance of food resources in preventing mass extinction.(C) To illustrate a comparison between organisms that live on the land and those that live in the ocean.(D) To point out that certain species could never become extinct.7. According to paragraph 2, evidence from fossils suggests that(A) Extinction of species has occurred from time to time throughout Earth's history.(B) Extinctions on Earth have generally been massive(C) There has been only one mass extinction in Earth's history.(D) Dinosaurs became extinct much earlier than scientists originally believed.8. The word "finding" in line 20 is closest in meaning to(A) published information(B) research method(C) ongoing experiment(D) scientific discovery9. Which of the following can be inferred about the theory mentioned in Line 21-23?(A) Many scientists could be expected to disagree with it.(B) Evidence to support the theory has recently been found.(C) The theory is no longer seriously considered.(D) Most scientists believe the theory to be accurate.10. In paragraph 3, the author makes which of the following statements abouta species' survival?(A) It reflects the interrelationship of many species.(B) It may depend on chance events.(C) It does not vary greatly from species to species(D) It is associated with astronomical conditions.11. According to the passage , it is believed that the largest extinction of a species occurred(A) 26 million years ago(B) 65 million years ago(C) 225 million years ago(D) 250 million years agoANSWER KEYSPASSAGE 77 BCDCD AADAB C。