A large area plastic scintillator detector array for fast neutron measurements
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重庆2024年07版小学英语第四单元测验卷考试时间:100分钟(总分:140)A卷考试人:_________题号一二三四五总分得分一、综合题(共计100题)1、听力题:A _______ is a reaction that releases light and heat.2、听力题:A __________ is a visual representation of a chemical reaction.3、听力题:The playground is _______ (fun) for kids.4、What do you call the first letter of the alphabet?A. AB. BC. CD. D答案:A5、听力题:A __________ is a measure of how tightly packed particles are in a substance.6、听力题:The __________ is a region known for its handicrafts.7、What is 7 + 6?A. 12B. 13C. 14D. 15答案: B8、听力题:The chemical formula for amyl acetate is ______.My grandma loves to share her __________ (传统故事).10、How many eyes does a typical person have?A. OneB. TwoC. ThreeD. Four11、填空题:A ________ (大象) is the largest land animal and has a long trunk.12、听力题:The __________ is the movement of the earth's plates.13、听力题:The girl loves to ________.14、听力题:A solution that has a higher concentration of solute than solvent is called a ______ solution.15、community service project) addresses local challenges. 填空题:The ____16、What do we call a piece of furniture you sleep on?A. ChairB. SofaC. BedD. Table17、听力题:The Earth’s atmosphere protects us from harmful ______ (radiation).18、How many legs does a spider have?A. 6B. 8C. 10D. 1219、填空题:The __________ (历史的多样性视角) enrich discussions.20、填空题:I call my grandfather . (我称呼我的祖父为)They play _____ (football/piano) after school.22、What do you call the process by which plants lose water?A. PhotosynthesisB. TranspirationC. RespirationD. Germination答案:B23、What is the name of the famous bridge in San Francisco?A. Golden Gate BridgeB. Brooklyn BridgeC. Tower BridgeD. Sydney Harbour Bridge答案:A24、选择题:What do we drink in the morning?A. MilkB. WaterC. JuiceD. All of the above25、听力题:The balloon is ___ (floating/deflating).26、听力题:The process of breaking down food is a type of _____ reaction.27、听力题:The train is ______ (fast) and convenient.28、What is the name of the first artificial satellite launched into orbit?A. Sputnik 1B. Explorer 1C. Vanguard 1D. Luna 129、听力题:The boy has a new ________.30、What is the name of the first living creature in space?A. LaikaB. BelkaD. Yuri31、Which of these is a mode of transportation?A. AppleB. TrainC. ChairD. House32、What do you call a group of wolves?A. PackB. FlockC. SchoolD. Pride答案:A33、听力题:Astrobiology studies the possibility of ______ in the universe.34、填空题:My family has a ______ at home.35、听力题:A _______ is a process that involves cooling.36、听力题:She is _____ (drawing) with chalk.37、听力题:The chemical formula for carbon dioxide is __________.38、听力题:A sound's pitch is determined by its frequency, while its loudness is determined by its ______.39、填空题:My brother is my adventurous _______ who loves to explore nature.40、填空题:My best friend is __________. (忠诚)41、填空题:My mom cooks ______ (美味的) food.42、What is the capital of Mongolia?A. UlaanbaatarC. DarkhanD. Choibalsan43、听力题:A _______ is a process that uses heat to change a substance.44、听力题:A __________ is a mixture that has uniform composition throughout.45、听力题:My cousin is very ____ (funny) and makes me laugh.46、What do you call the act of making food ready for eating?A. CookingB. PreparingC. BakingD. Grilling答案: B47、填空题:The ______ (种植园) produces coffee beans.48、填空题:I enjoy spending time with my __________. (家人)49、听力题:The chemical formula for potassium perchlorate is _____.50、填空题:The kitten likes to _______ (睡觉) on my lap.51、What type of music is characterized by strong rhythms and often includes drums?A. ClassicalB. JazzC. RockD. Pop答案:C52、听力题:The ________ (teamwork) improves results.53、What is the capital of Bhutan?A. ThimphuB. ParoD. Phuentsholing答案:A54、What is the main ingredient used to make beer?A. CornB. WheatC. BarleyD. Rice答案:C55、What is the name of the fictional character who wears a red coat and has a pet fox?A. Peter PanB. Paddington BearC. Winnie the PoohD. The Gruffalo答案: B56、填空题:My ___ (小狗) loves to dig in the sand.57、What is the opposite of ‘strong’?A. WeakB. PowerfulC. ToughD. Sturdy58、填空题:The __________ (历史的丰富内涵) inspire creativity.59、选择题:What do we call the time when the sun rises?A. DawnB. NoonC. DuskD. Midnight60、How many players are on a soccer team?A. ElevenB. TenC. NineD. Twelve61、What do you call the liquid that comes from trees?A. GumC. SapD. Juice答案:C62、填空题:My neighbor, ______ (我的邻居), has two cats.63、填空题:The teacher helps _____ (学生) reach their goals.64、听力填空题:I think that every skill learned is a step towards our __________.65、What do you call a young goat?A. KidB. CalfC. FoalD. Lamb66、What do plants need to grow?A. Sunlight, water, and soilB. Darkness, salt, and airC. Sugar, heat, and rocksD. None of the above答案:A67、听力题:The capital of Vietnam is __________.68、What is the shape of a basketball?A. SquareB. TriangleC. RectangleD. Circle答案:D69、填空题:I enjoy doing ______ (运动) because it keeps me fit and active. My favorite is ______ (游泳).70、填空题:My cousin has a __________仓鼠. (可爱的)The _____ (ocean) is blue.72、听力题:A rainbow is formed by the ______ (refraction) of light.73、填空题:I have a _____ (跳棋) set that I play with my family.我有一个跳棋游戏,和家人一起玩。
最新高三英语阅读理解(科普环保)的基本方法技巧及练习题及练习题(含答案)一、高中英语阅读理解科普环保类1.犇犇阅读下列短文,从每题所给的A、B、C和D四个选项中,选出最佳选项。
A team of international scientists is due to set off for the world's biggest iceberg in a mission aiming to answer fundamental questions about the impact of climate change in the polar regions. The scientists, led by the British Antarctic Survey (BAS), are trying to reach a newly revealed ecosystem that had been hidden for 120,000 years below the Larsen C ice shelf.Last year, part of the Larsen C ice shelf calved (崩解) away, forming a huge iceberg-A68—which is four times bigger than London, and revealing life beneath for the first time. Now scientists say it is a race against time to explore these new ecosystems before they are transformed to the light. Marine biologist Dr Katrin Linse from the BAS is leading the mission."The calving of A68 provides us with a unique opportunity to study marine life as it responds to a huge environment change," she said. "It is important that we get there quickly before the undersea environment changes as sunlight enters the water."Professor David Vaughan, science director at the BAs, said, "We need to be bold (大胆的) on this one. Larsen C is a long way south and there's lots of sea ice in the area, but this is important science, so we will try our best to get the team where they need to be. He said climate change had already affected the sea around Antarctica and is warming some coastal waters. "Future warming may make some habitats warm. Where these habitats support unique species that are adapted to love the cold and not the warm, those species are going to either move or die."There is growing concern about the possible impact of climate change in the Antarctic. Earlier this month, a report revealed that melting ice sheets in Greenland and Antarctica are speeding up the already fast pace of the sea level rise. The research, published by the National Academies of Science, Engineering and Medicine, said, "At the current rate, the world's ocean will be, on average, at least 60cm higher by the end of the century." However, it found that the process is accelerating, and more than three quarters of the acceleration since 1993 is due to melting ice sheets in Greenland and Antarctica, the study shows.(1)Why are the scientists eager to go to the iceberg?A. To study how the iceberg was formed.B. To study a newly discovered ecosystem.C. To explore a new way to prevent climate change.D. To explore the geography of the Larsen C ice shelf.(2)What do the underlined words "this one" in the fourth paragraph refer to?A. The Larsen C ice shelf.B. Climate change in Antarctica.C. The A68 iceberg with the ecosystem beneath it.D. The condition of animal species in Antarctica.(3)What can we learn about the A68 iceberg from the text?A. It is as big as London.B. It is part of an ice shelf in the Arctic.C. It will disappear in a very short time.D. It has uncovered an unknown ecosystem in Antarctica.(4)What can we infer from the last paragraph?A. There is no need to worry about climate change in Antarctica.B. The ice sheets in Greenland and Antarctica are melting at a steady rate.C. Many creatures living in deep water will die out due to climate change.D. By 2100, the sea level will have risen to a much higher level than now.【答案】(1)B(2)C(3)D(4)D【解析】【分析】本文是一篇说明文,南极地区的拉森C冰架崩解形成了一座巨大的冰山A68 iceberg。
2021年高考英语能力拓展之概要写作21科学与技术21.阅读下面短文,根据其内容写一篇60 词左右的内容概要。
Two years ago, Li Yuhua's daughter taught her how to shop online. Since then, the 51-year-old farmer in Wushan has been a regular online shopper. Shoppers like Li Yuhua are the new target for China's ecommerce giants, including Alibaba Group, which operates the Taobao platform, and . Rural China added 3 million more Internet users in the first half, taking the total number to 225 million, or 26.3%, of the country's total Internet population of 854 million, according to a report on rural ecommerce development released last week by the China International Electronic Commerce Center. That helped improve rural online sales in the first half of the year by 21% to 777.1 billion yuan (US$109.6 billion), outpacing the national growth rate by 3.2 percentage points.''However, it is a little bit early to say that China's ecommerce battlefield is moving to rural China, '' said Chen Tao, a senior analyst at consultancy Analysys. Unlike urban residents, most rural Chinese haven’t experienced ecommerce shopping. While that provides online platforms with one of the last undeveloped markets for ecommerce, progress has been slow due to the lack of infrastructure(基础设施)and logistics(物流)support.To address that problem, China's second-largest ecommerce operator, hired more deliverymen and tested drone(无人机) delivery services to improve service in rural China. Alibaba Group, China's largest ecommerce player, announced in April last year that it had invested US$717 million in Huitongda Network Co., which helps to boost sales in 15,000 towns across 18 provinces.Another inhibiting factor in the development of rural ecommerce is the income gap. In 2018, annual per capita disposable income(人均可支配收入)in rural areas was 14,600 yuan (US$2,065) compared with 39,300 yuan (US$5,559) in cities. ''Lower disposable incomes in rural areas limit the consumption,'' said analyst Chen. ''It also takes time to educate rural residents to acceptecommerce services as most of them are new to online. There is still a long way to go to popularize online shopping in rural China.''_______________________________________________________________________________ _______________________________________________________________________________ _______________________________________________________________________________ ___________________________________________________________________2.阅读下面短文,根据其内容写一篇60词左右的内容概要。
阅读理解When you think of Arcitc答案When you think of the Arctic(北极),you imagine an icy land of pure white snow.Others imagine it as the last reall y clean place left on Earth.We have polluted the deepest oc eans with plastic trash,and now,CNN sys,"It's the Arctic's turn."German scientists have recently found micro plastics(微塑料)in Arctic snow,the Associated Press reported.Micro pl astics are pieces of plastic smaller than 5 millimeter.Sadl y,the scientists found 1,800 pieces of micro plastic per li ter of snow.How is plastic pollution reaching the Arctic?According to scientists,"It's obvious that the majority of the micro plastic in the snow comes from the air."They fall off of pl astic objects and are moved by the wind,just like dust.They mix with ice in the air and fall to the ground as snow.Fin ding these plastics in Arctic snow means that we may breath e them in.An even higher amount of micro plastic was found in the snow around cites.Are they bad for us?Scientists cannot answer this quest ion for now,according to the World Health Organization.We d o know that our bodies cannot take in"large"pieces of microplastics.However,if the plastics are small enough,they can find ways into our bodies and stay there for a long time,w hich can be bad for our health.What's more,earlier studies have shown that micro plastics may contribute to lung cance r risk.Micro plastics have also been found in rivers and ocean s around the world.Previous research has found that they fl ow over long distances and into our oceans,damaging ecosyst ems(生态系统)along the way.They start in our waste water, when we wash clothes with plastic fibers.The waste water th en flows into rivers and out to sea,where they are eaten by sea animals.If people then eat these animals,it means that we're eating them as well.(1)According to the first two paragraphs,what happened to the Arctic?A.It became the last clean place on Earth.B.Much plastic trash was left for pick-up.C.It has already been polluted by micro plastics.D.1,800 pieces of micro plastic were found there.(2)What's the main idea of Paragraph 3?A.What is the Arctic snow like?B.How dangerous the micro plastics are!C.Where does the micro plastic come from?D.How to cut down on micro plastics in the Arctic?(3)What does the last paragraph tell us?A.We can't wash clothes with plastic fibers.B.Sea animals are in danger because of micro plastics.C.Micro plastics are mainly found in rivers and oceans.D.Micro plastics can be bad for the environment and our health.(4)Where can we probably find the passage?A.In a magazine.B.In a storybook.C.In an advertisement.D.In a guide book.【解答】(1)C(2)C(3)D(4)A【分析】(1)文章大意:本文主要介绍了北极已经被微塑料污染以及这种污染给环境和人类生活带来的影响。
塑料袋不能分解英语作文Plastic bags are a big problem. They are everywhere and they never go away. They can last for hundreds of years in the environment, causing harm to animals and polluting our oceans and land.The problem with plastic bags is that they are not biodegradable. This means that they do not break down naturally over time like other materials. Instead, theyjust break into smaller and smaller pieces, which can be harmful to animals if they ingest them.When plastic bags end up in the ocean, they can be mistaken for food by marine animals. This can lead to the animals getting sick or even dying because of the plasticin their stomachs. It's a big problem for the health of our oceans and the creatures that live in them.Plastic bags also contribute to the pollution of our land. They can be found littered everywhere, from citystreets to rural areas. This not only makes our environment look dirty and unattractive, but it also poses a threat to wildlife that may become entangled in the bags or mistake them for food.One of the biggest issues with plastic bags is that they are used for such a short amount of time before being thrown away. Many people use plastic bags just once or twice before disposing of them, which means that a huge amount of waste is created in a very short period of time.In conclusion, the problem with plastic bags is clear. They are a major source of pollution and harm to our environment. It's important for us to find alternatives to plastic bags and to reduce our use of them as much as possible.。
武汉2024年09版小学英语第五单元测验卷(有答案)考试时间:90分钟(总分:140)A卷考试人:_________题号一二三四五总分得分一、综合题(共计100题共100分)1. 听力题:The ______ is famous for her acting skills.2. 听力题:The _____ (star/planet) is bright.3. 听力题:The formula for ammonia is _______.4. 填空题:The otter holds hands when it _________ (睡觉).5. 填空题:The zebra has black and _________ (白色) stripes.6. 听力题:I want to ___ a new toy. (get)7. 听力题:A _______ is a large area of sand or pebbles along the edge of the sea.8. 填空题:Plants help regulate the ______ of the atmosphere by absorbing carbon dioxide.(植物通过吸收二氧化碳有助于调节大气中的气体。
)9. 填空题:_____ (果树种植) requires specific knowledge.10. 选择题:What do you call the place where we keep our cars?A. GarageB. KitchenC. Living RoomD. Bedroom答案: A11. 填空题:A ______ (植物分类) helps identify species.12. 填空题:The dolphin leaps joyfully out of the ______ (水).13. 选择题:What is the name of the holiday that celebrates the New Year?A. ChristmasB. ThanksgivingC. New Year's DayD. Independence Day答案:C14. 听力题:The ____ hops quickly and loves to chase after things.15. 填空题:The country known for its chocolate is ________ (比利时).16. 听力题:We need to ______ our homework. (finish)17. 听力题:The boy plays the ________.18. 选择题:What do you call a person who works in a restaurant?A. ChefB. WaiterC. CookD. All of the above答案:D19. 选择题:What is the value of 4 + 4 6?A. 2B. 4C. 6D. 8答案:AThe ancient Romans utilized ________ (混凝土) in their construction.21. 填空题:Seeds need ________ (阳光) and water to germinate.22. 填空题:My ________ (玩具名称) makes bubbles when I play with it.23. 填空题:My favorite animal is a ________ (小狗).24. 填空题:This girl, ______ (这个女孩), is studying to be a veterinarian.25. 填空题:My ________ (父母) always support me in my activities.26. 听力题:The process of oxidation involves __________ losing electrons.27. 填空题:My pet ___ (小鸟) sings every morning.28. 听力题:The chemical symbol for yttrium is _______.29. 填空题:We usually have ________ for lunch at school.30. 选择题:What is the main ingredient in chocolate?A. CocoaB. SugarC. MilkD. Butter答案:A31. 选择题:What is the main component of stars?A. WaterB. HydrogenC. OxygenD. CarbonHow many states are in the USA?A. 48B. 50C. 52D. 54答案:B33. 听力题:The _____ (socks) are mismatched.34. 听力题:A __________ is a mammal that is known for its intelligence.35. 选择题:What is the name of the famous fairy tale character who had long hair?A. CinderellaB. RapunzelC. Snow WhiteD. Sleeping Beauty36. 填空题:We have a ______ (特别的) day planned for school.37. 听力题:The _______ of a solution can change with temperature.38. 填空题:The first university in the world was established in ______ (摩洛哥).39. 选择题:What do we call a person who makes bread?A. BakerB. ChefC. CookD. Waiter40. 选择题:What do you call the animal that has a shell and moves slowly?A. RabbitB. SnailC. CatD. Dog答案: BWhat do you see in the sky at night?A. SunB. MoonC. CloudsD. Rain答案: B42. 听力题:A ____ is a playful animal that enjoys splashing in water.43. 填空题:My friend is a _____ (教师) who teaches math.44. 听力题:The ________ (networking) helps build connections.45. 选择题:What is the capital of Greece?A. AthensB. RomeC. ParisD. Madrid46. 填空题:When it rains, I love to watch the __________ flow. (水)47. 选择题:What is the name of the famous ancient city in Greece?A. AthensB. SpartaC. DelphiD. Corinth答案:A48. 填空题:I enjoy learning new ______ (技能) and hobbies to expand my interests.49. 填空题:I enjoy ______ (进行) creative writing.50. 填空题:Did you see the _____ (小狗) chasing its owner?A molecule with a net charge is called a(n) _______.52. 听力题:The chemical formula for phenylalanine is ______.53. 听力题:The _______ offers a variety of benefits.54. 听力题:The ______ shares her experiences with others.55. 选择题:What is the term for the natural satellite of the Earth?A. PlanetB. SunC. MoonD. Star答案: C56. 填空题:Did you see a _______ (小家鼠) in your house?57. ts can ________ (自我传播). 填空题:Some pla58. 填空题:I like to watch ________ (比赛) on TV.59. 听力题:I need to ________ my homework.60. 听力题:The __________ is the part of the atom that carries a negative charge.61. 听力题:Space is mostly _____, with very few particles.62. 填空题:The __________ were ancient monuments built by the Mayans. (金字塔)63. 听力题:A solution that has a low concentration of solute is called a ______ solution.64. 填空题:We should _______ (关心) our elders.My sister enjoys __________ (艺术创作).66. 听力题:A liquid has a definite volume but takes the shape of its ______.67. 选择题:Which holiday is celebrated on December 25th?A. ThanksgivingB. HalloweenC. ChristmasD. New Year答案:C68. 填空题:Plants can be used for __________ (食物和药物).69. 选择题:What do we call the system of governing a country?A. EconomyB. PoliticsC. GovernmentD. Law答案:C70. 听力题:I have two ___. (sisters)71. 听力题:I love ________ with my family.72. 听力题:I want to be a ___. (doctor)73. 听力题:I see ________ in the water.74. 听力填空题:I think technology is amazing, especially __________ because __________.75. ts can grow in _____ (沙土). 填空题:Some pla76. 选择题:Which animal is known for its ability to change colors?A. ChameleonB. FrogC. LizardD. Snake77. 听力题:The weather is ______ (cold) in winter.78. 选择题:How long does it take for the Earth to orbit the Sun?A. 24 hoursB. 30 daysC. 365 daysD. 10 months79. 听力题:A _______ is a reaction that involves the combination of substances.80. 填空题:________ (植物可持续性) is vital for future.81. 选择题:What is the capital of Venezuela?A. CaracasB. BogotaC. QuitoD. Lima82. 选择题:What is the name of the fairy tale character who had a magic mirror?A. CinderellaB. Snow WhiteC. RapunzelD. Belle83. 选择题:What is the opposite of "happy"?A. SadB. JoyfulC. ExcitedD. Angry答案: A. Sad84. 听力题:The Earth's crust is essential for sustaining ______.85. 选择题:What do you use to write?A. SpoonB. ForkC. PencilD. Plate答案: C86. 填空题:A _____ (小鸡) hatched from an egg.87. 选择题:Which of these is a holiday?A. MondayB. ChristmasC. JanuaryD. Summer88. 选择题:What do you call a baby dog?A. KittenB. PuppyC. CubD. Chick89. 听力题:I have a ______ of colorful markers. (set)90. 填空题:My favorite thing to do during summer is ______.91. 填空题:I like to watch ______ shows on television.92. 听力题:A beam of light can be ______ by a mirror.93. 选择题:Which of these is a primary color?A. PurpleB. OrangeC. BlueD. Brown94. 选择题:What do we call the process of changing from a caterpillar to a butterfly?A. MetamorphosisB. EvolutionC. TransformationD. Development答案:A95. 听力题:The Great Wall of China was built to protect against ________.96. 听力题:Water is made of ______ and oxygen.97. 选择题:What is the capital of Vietnam?A. HanoiB. Ho Chi Minh CityC. Da NangD. Nha Trang98. 填空题:My uncle is my funny _______ who tells great jokes.99. 听力题:The cat purrs when it is _____ happy.100. 填空题:My favorite TV show is ________ (喜剧).。
小学上册英语第2单元全练全测(含答案)英语试题一、综合题(本题有100小题,每小题1分,共100分.每小题不选、错误,均不给分)1.What is the main language spoken in the USA?A. SpanishB. FrenchC. EnglishD. German2.What is the term for the speed of light?A. 300,000 kilometers per secondB. 150,000 kilometers per secondC. 100,000 kilometers per secondD. 1,000 kilometers per second答案:A3.The ______ (小鸭) quacks all day long.4.The chemical symbol for ytterbium is ______.5.The ice cream is ________ cold.6.The chemical formula for glucose is _____.7.ts have unique adaptations that help them ______. (某些植物有独特的适应性,有助于它们生存。
) Some pla8.What is the color of grass?A. GreenB. YellowC. BlueD. Red9.What do you call a story with magical elements?A. BiographyB. FictionC. Non-fictionD. History10.We have a _____ (照片) on the wall.11.The _______ can be a perfect subject for drawing.12. A _____ (果园管理) requires knowledge and care.13.The _____ (cake/pie) is delicious.14.What do we call a person who studies the effects of globalization?A. Global SociologistB. AnthropologistC. Political ScientistD. Historian答案:A15.I enjoy _______ stories before bed.16.The _____ (图书) are interesting.17.I see a _____ bird in the tree. (red/quick/small)18.The clock shows _____ (three/four) o'clock.19.What do we call a person who studies the stars?A. AstronomerB. AstrologerC. ChemistD. Geologist答案:A20.She is a _____ (科学家) who studies the environment.21.She is _______ (playing) with dolls.22.The bobcat has spotted _______.23.What is the capital of Japan?A. TokyoB. SeoulC. BeijingD. Bangkok答案:A24.The _____ (penguin) waddles on the ice.25.Emily is a ______. She loves animals.26.The __________ (古代帝国) often expanded through conquest.27.The flower needs water and _______ (花需要水和_______).28. A chemical reaction involves the rearranging of ______.29. A __________ is a low area between hills or mountains.30.What is 10 4?A. 5B. 6C. 7D. 8答案:B31.What do you call a large, flightless bird native to Australia?A. EmuB. KiwiC. PenguinD. Ostrich答案:A32.I like to ride my ________ in the neighborhood.33. A ______ is a type of animal that can be found in the forest.34.What do we call a person who studies the weather?A. MeteorologistB. ClimatologistC. GeologistD. Astronomer35.What do we call the act of sharing knowledge?A. TeachingB. EducatingC. InstructingD. All of the Above答案:D36.What do you call a popular social gathering?A. PartyB. MeetingC. ConferenceD. Event答案:A37.What is a synonym for "happy"?A. SadB. JoyfulC. AngryD. Tired答案:B38.What do you call a person who studies animals?A. BiologistB. ZoologistC. EcologistD. Ornithologist答案:B39.Which fruit is known for having seeds on the outside?A. AppleB. StrawberryC. BananaD. Peach答案:B40.What is the name of the famous ship that sank in 1912?A. BritannicB. TitanicC. LusitaniaD. Queen Mary答案:B41. A _______ is a compound that contains carbon.42.I have a _____ (跳绳) for exercise.43.h Revolution marked the rise of ________ (民主). The Fren44.This ________ (玩具) is a gateway to adventure.45.The rabbit's coat changes color in _______ (冬天).46.I love to decorate my _________ (玩具房间) with colorful items.47.The capital of England is __________.48.The flowers are ___. (beautiful)49.The ________ (果冻) is made from fruits.50.When I grow up, I want to make a difference in the _______ (世界). I believe everyone can help.51.My favorite animal is a ______ (大象). It is the largest land animal and is very ______ (温和).52. A ________ is an area that receives a lot of rain.53. A nuclear reaction changes the nucleus of an _______.54.The __________ (历史的多元性) enriches our collective narrative.55.The ______ has thick fur for warmth.56.I love _______ (我的家) because it is very _______ (舒适).57.What is the name of the line that marks the boundary between daytime and nighttime on a planet?A. TerminatorB. EquatorC. MeridianD. Axis58.What do you call a story that is made up?A. BiographyB. FictionC. Non-fictionD. History答案:B59.The __________ (历史的参与者) play crucial roles in shaping events.60.When I want to get my dad's attention, I say, "Dad, !" (当我想引起我爸爸的注意时,我会说:“爸爸,!”)61.I can ______ (讲) a story very well.62.I brush my _____ (牙齿) every night.63.In which country is the Great Wall located?A. JapanB. IndiaC. ChinaD. Thailand64.The ancient civilizations of Europe are known for their ________ legacies.65.What is the capital city of Greece?A. AthensB. RomeC. IstanbulD. Cairo66. A ______ is a large area of flat land.67.My brother is very ________ (聪明).68.Chemical reactions can be reversed through _____.69.What is the name of the fairy tale character who has seven dwarfs?A. CinderellaB. Snow WhiteC. RapunzelD. Belle答案:B70.What is the color of the sky on a clear day?A. BlueB. GreenC. YellowD. Red答案:A71.The bear catches fish in the ______.72.Tectonic plates float on the __________ beneath them.73.How many sides does a square have?A. 3B. 4C. 5D. 6答案:B74. A dolphin jumps gracefully out of the _______ and plays.75.The ________ is known for its long neck.76.The _____ (grass) is green.77.Chemical bonds can be ionic or ______.78.I like to _______ (与朋友聚会)。
包头2024年05版小学3年级上册英语第3单元暑期作业(含答案)考试时间:90分钟(总分:120)B卷一、综合题(共计100题共100分)1. 听力题:We are going to the ___. (planetarium)2. 填空题:My favorite way to start a letter is with "Dear ." (我开始一封信的最喜欢方式是“亲爱的。
”)3. 填空题:The __________ (历史的启迪) enlightens minds.4. 听力题:The Age of Exploration began in the ________ century.5. 听力题:The chemical formula for methane is ________.6. 听力题:The __________ can indicate areas at risk of geological hazards.7. 填空题:My dad is a great __________ (模范) of kindness.8. 选择题:What is the term for a star that has exploded and left behind a dense remnant?A. SupernovaB. Neutron StarC. Black HoleD. Pulsar9. 填空题:Her favorite animal is a _______.What is the capital city of Japan?A. BeijingB. SeoulC. TokyoD. Bangkok答案: C11. 填空题:Different plants have different ______ (生长条件).12. 填空题:I can't wait to __________ (动词) with my __________ (玩具名) again.13. 选择题:What is the capital of Japan?A. TokyoB. KyotoC. OsakaD. Hiroshima答案: A14. 填空题:The ant works together in a _________. (群体)15. 填空题:The rainbow trout is a beautiful _________ (鱼).16. 填空题:My dad loves __________ (进行科技探索).17. 填空题:The park is _______ (适合家庭).18. 听力题:The study of ancient geological formations is known as ______.19. 选择题:What do you call the science of studying the stars and planets?A. BiologyB. ChemistryC. AstronomyD. Geology答案:CA ____(green roof) supports biodiversity in urban areas.21. 听力题:I have _____ of friends in my class. (lots)22. 选择题:What do we call the art of folding paper into shapes?A. OrigamiB. PaintingC. SculptingD. Drawing答案:A23. 填空题:The __________ (历史的反响) can lead to change.24. 选择题:What is the name of the famous mountain in Africa?A. KilimanjaroB. Mount KenyaC. Atlas MountainsD. Rwenzori Mountains25. 听力题:She has a _____ (dog/cat) at home.26. 填空题:My cousin is very __________ (活泼的) and friendly.27. 听力题:A __________ has a long neck and legs, often found in Africa.28. 听力题:I want to travel to _____ (France/Fridge).29. 选择题:What do we call the time when the sun rises?A. SunriseB. SunsetC. DuskD. Twilight答案: A30. 听力题:The city of Tbilisi is the capital of _______.I gave my friend a ________ for her birthday.32. 填空题:The toy robot can ______.33. 填空题:My grandma loves to _______ (动词) in her garden. 她的花园很 _______ (形容词).34. 听力填空题:I love learning about climate change and how to protect the __________.35. 填空题:I love to explore ________ (历史遗址) during trips.36. 选择题:What do you call a person who designs buildings?A. ArchitectB. EngineerC. ContractorD. Builder答案: A37. 选择题:What do you call the part of the plant that grows underground?A. LeafB. StemC. RootD. Flower38. 选择题:What do you call a scientist who studies space?A. BiologistB. ChemistC. AstronomerD. Physicist答案: C39. 听力题:The Earth's surface is composed of various geological ______.40. 填空题:The rabbit's fur keeps it _________. (温暖)41. 听力题:I like to _____ at the park. (play)My brother collects ________.43. 填空题:My grandma tells me stories about ______ (动物). They are always very ______ (有趣).44. 听力题:The chemical symbol for scandium is ______.45. 选择题:What is the main ingredient in pancakes?A. FlourB. SugarC. MilkD. Eggs46. 填空题:The prairie dog lives in _________ (地下).47. 听力题:The chemical formula for glucose is __________.48. 听力题:The Earth's ______ is made up of different types of ecosystems.49. 填空题:________ (植物生长机制) reveals secrets.50. 填空题:I find ________ (机械工程) very interesting.51. 听力题:The chemical formula for sodium phosphate is ______.52. 听力题:A ____ has soft fur and loves cuddling.53. 选择题:What is the name of the famous museum in Paris?A. LouvreB. UffiziC. MetD. Hermitage54. 填空题:We need to _______ (保护) endangered species.The _____ (花卉香气) enhances the atmosphere.56. 选择题:What do we call the hard outer covering of an egg?A. ShellB. YolkC. WhiteD. Albumen答案: A. Shell57. 选择题:Which shape has four equal sides?A. TriangleB. RectangleC. SquareD. Circle答案:C58. 填空题:A dolphin plays with ________________ (海浪).59. 填空题:My cousin is very __________. (有趣)60. 填空题:In spring, many trees start to grow new ______. (在春天,许多树开始长出新的叶子。
第二十二讲九年级 Units 13—14Ⅰ.单项填空1.—There are a lot of of bike riding.—I quite agree. It's good for the environment and it saves money.A.instructionsB.instrumentsC.advantagesD.products2.—She always thinks of others.—Yes. Everyone thinks she is a girl.A.caringB.hardworkingC.braveD.polite3.—Don't the waste paper.We can collect and recycle it.—You're right.Everyone should be a greener person.A. blow awayB. give awayC. throw awayD. put away4.—The milk shake tastes good. How do you make it?—It's easy. Just follow the .A.discussionsB. instructionsC.expressionsD. decisions5.[2018合肥50中三测]The price of housing in Hefei is so high that most young men can't afford a flat.A. buyingB. to buyC. boughtD. buy6.—It's his new book, but I think it is more interesting than his other books. —I agree with you. His latest book is up to his highest .A. choiceB. standardC. purposeD. wealth7.As a teacher, I love being with my students. You can't imagine how much they knowledge!A. are thirsty forB. are famous forC. are good forD. are responsible for8.[2018合肥45中三模]—Many teenagers put mobile gaming other things and spend too much time on it.—That's really bad.A. thanks toB. as forC. ahead ofD. along with9.[2018合肥瑶海区一模]How kind you are! You always do what you can me.A. helpB. helpingC. helpsD. to help10.—Mr. Black, could you tell me ?—At 10:00 tomorrow morning.A.where we'll go hikingB.when we'll have a meetingC.whether you'll come to my birthday partyD.how we'll go to ShanghaiⅡ.完形填空[2018宣城二模]When I was in primary school, I argued with a boy in my class. I have forgotten what the argument was about, but I 1 forget the lesson I learned that day.I thought he was wrong, but he thought I was wrong. I was very 2 .The teacher decided to teach us a lesson. She asked the boy to stand by one side of her 3 and me on the other. In the middle of her desk was a large object. She asked the boy what 4 it was. "White," he answered quickly.I couldn't 5 what he said. It was obviously black. Another argument 6 between him and me. The teacher asked us to 7 arguing and change places. Then she asked me the object's color. I had to answer, "White."8 , the object had two sides with different colors. From his side it was white and from my side it was black.Please remember that you must stand in the other person's shoes and look 9 the situation through his or her eyes. It's 10 for us in our life.1.A. ever B. always C. never D. just2.A. angry B. sad C. lucky D. happy3.A. desk B. body C. chair D. box4.A. size B. price C. color D. shape5.A. remember B. hear C. believe D. help6.A. opened B. started C. failed D. ended7.A. begin B. enjoy C. forget D. stop8.A. At last B. In fact C. First of all D. In a word9.A. at B. for C. up D. after10.A. difficult B. dangerous C. necessary D. impossibleⅢ.阅读理解A"Save the whales!" That was what the picture on Jake Smith's bedroom wall said. Jake liked having a picture that said something important, and that showed he cared. He just never expected to get a chance to save a real whale, one right in his own neighborhood.It was a Saturday morning when the newspaper first reported the whales' coming.A group of the animals were swimming close to the beach in Jake's hometown. All the local people rushed out to the beach to see them. They were expecting a beautiful show, better than a movie.Then one whale swam in the direction, directly towards land. It came with the waves(海浪), and when the waves left, its huge body was on the sand. Suddenly, Jake and his family and all the others were no longer sightseers. They had to become rescuers(救援者). A few people ran towards the animal. They pushed and tried to force the whale back into the water, but it was no use.An animal rescue team soon arrived in a truck with heavy lifting machinery, to help move the animal. Jake and his family couldn't do much on the beach, so they went back to their house and made sandwiches and hot tea for the rescuers. At least, Jake thought, they could help in some way.Back to the beach, they offered the food to the rescuers and were happy to see that it was needed. It was getting dark. Some people lined up their cars along the beach and shone the headlights on the sand. The rescuers would not give up. After trying many times they were finally able to lift the whale into the water. Everyone cheered when it headed out to the sea. It swam out about a mile and then disappeared for a moment under the sea. Then, in what looked like a jump of joy, it rose high above the water — a thank-you to those who had worked so hard to save its life.1. What does the picture on Jake's wall tell us about him?A.He lived near the ocean.B.He cared about the environment.C.He worked as an animal rescuer.D.He thought whales were the most beautiful animals.2. Why did the local people go down to the beach that morning?A.To swim with the animals.B.To help rescue the animals.C.To see the animals swimming.D.To watch a movie about animals.3. Jake and his family helped save the whale .A.by calling the rescue teamB.by asking their neighbors for helpC.by giving the rescuers food and drinkD.by controlling the people on the beach4. Who played the biggest role during the rescue?A.The Smiths.B.Jake's neighbors.C.The movie makers.D.The rescue team.5. Which of the following can be the best title of the passage?A.A Whale ShowB.Save the WhalesC.Jake's DreamD.The Whales' ComingB[2018重庆A卷改编]Scientists in Britain and the United States have made a new kind of enzyme(酵素)that eats plastics(塑料). With its help, plastics can be turned into smaller parts and go away quickly. Scientists believe that, in the future, it could solve the problem of plastic pollution.The enzyme is able to break down PET, a form of plastic. PET was first made in the 1940s and is now widely used to make plastic bottles. It can remain in the environment for many years and pollute large areas of land and water. So it has always been a headache to deal with the waste from PET and other plastics.The researchers made the discovery(发现)while examining the structure of a natural enzyme in Japan. They found that the natural enzyme was helping to break down PET plastics. So, they decided to make small changes to the enzyme by adding some amino acids(氨基酸). It made the natural enzyme's plastic-eating abilities work faster and better.John McGeehan, one of the lead researchers, said, "We've made an improved enzyme. It's better than the natural one. And we are trying to make more improvements to it." He went on, "The enzyme is not harmful to humans or animals, and it is friendly to the environment. So we are considering putting it into wider use."The team is now trying to make the enzyme break down PET in large quantities(大量地). "We'll see that the plastic pollution may be stopped with this technology. However, there is still a long way to go," John McGeehan added.6.According to the scientists, the enzyme may solve the problem ofpollution.A. airB. waterC. lightD. plastic7.The underlined phrase "break down" in the passage probably means " " in Chinese.A. 实验B. 生产C. 发明D. 分解8.Researchers discovered that a natural enzyme helped eat plastics .A. in BritainB. in the USC. in JapanD. in ChinaⅣ.书面表达时光精灵带走了三年相伴的岁月,却给我们留下了满满的收获。
备战 2021 高考英语原汁原味外刊热点话题阅读特辑day9: The Marine plastic problem is bound to get worse海洋塑料问题注定会越来越严重课前导读: 《科学》杂志上发表的一项新研究表明,流入世界海洋的塑料数量将急剧上升,对于这一趋势,那些试图减少塑料垃圾的努力将无济于事。
精彩英文 The annual inflow of plastic could nearly triple from 2016 to 2040, the study found, and even if companies and governments meet all their commitments to tackle plastic waste, it would reduce the projection for 2040 by only 7%, still a more-than twofold increase in volume. The study’s authors, the nonprofit Pew Charitable Trust and sustainability consulting firm Systemiq Ltd., set out a range of measures to stem the flow and called on businesses and governments to do more to reduce the use of plastic. They developed what they say is a first-of-its-kind model of the global plastics-supply chain—from production to consumption to disposal—using data and input from 17 experts from various regions. Consumer and regulatory pressure has prompted many of the world’s biggest consumer-goods companies to commit to making all their packaging reusable, recyclable or compostable within the next five years. Businesses have also pledged to use more recycled content in their packaging, often touting suchpromises to woo shoppers. Waste-reduction advocates say those commitments aren’t enough because they focus on recycling plastic, rather than making and using less of it. Companies like Walmart Inc.,Nestle and Procter & GambleCo. say they plan to eliminate unnecessary packaging and use more refillable containers, but few have set measurable targets for doing so. 【报刊词汇预习】 1. annual 每年的 adj 2. triple 三倍的 adj. 3. inflow 流入 n. 4. commitment 承诺 n. 5. tackle 处理 vt. 6. projection 投影 n. 7. volume 体积 n. 8. twofold 双重的 adj. 9. nonprofit 非营利性 adj. 10. sustainability 持续性/səˌsteɪnəˈbɪləti/ 11. consulting 咨询的 adj. 12. stem 阻止 vt 13. a first-of-its-kind 首创的 adj. 14. plastics-supply 塑料供应的 adj. 15. disposal 处置 n 16. data 数据 n 17. input~ (into/to sth)~ (of sth)投入资源(指时间、知识、思想等);投入;输入 vt/nHer specialist input to the discussions has been very useful. 她在这些讨论中提供的专家建议很有 助益。
a rXiv:089.794v1[nucl-ex]4Se p28A large area plastic scintillator detector array for fast neutron measurements P.C.Rout a ,b ,D.R.Chakrabarty a ,b ,V.M.Datar a ,b ,Suresh Kumar a ,E.T.Mirgule a ,A.Mitra a ,V.Nanal c and R.Kujur a a Nuclear Physics Division,Bhabha Atomic Research Centre,Mumbai-400085,India b Homi Bhabha National Institute,Bhabha Atomic Research Centre,Mumbai-400085,India c Department of Nuclear and Atomic Physics,Tata Institute of Fundamental Research,Mumbai-400005,Indiameasured neutron spectra in7Li(p,n1)7Be∗(0.429MeV)at E p=6.3to19MeV and12C+93Nb at E(12C)=40MeV.areal coverage,the detector was shown to have good TOF and position reso-lution using the timing information from both the PMTs.An array consisting of a number of such long scintillators stacked one above the other is a cheaper and simpler alternative to an array of a larger number of discrete detectors with a comparable efficiency.For example a1m2array with16bars of cross section6cm×6cm needs32PMTs of5cm diameter.An array of similar overall dimensions but more granularity could have256plastic scintillators each of size6cm×6cm and would require256PMTs.An array of49square plastic scintillators of size14cm×14cm could be viewed by12.7cm diameter PMTs or5cm diameter PMTs with light guides.Either option would increase the complexity and cost of the detector system.We have chosen to set up a 1m×1m plastic detector array consisting of16long scintillators.The paper is organized in four sections.Thefirst section gives details of the detector array.In the next section the measured time,position and energy response to electrons and monoenergetic neutrons is described.The electron measurements were carried out using radioactive sources while those for neu-trons were done using the7Li(p,n1)7Be*(0.429MeV)reaction at proton ener-gies from6.3to19MeV.The third section outlines the Monte Carlo simulation of the response of the plastic detector to fast neutrons.Finally,an example of a measured neutron spectrum in the reaction12C+93Nb at E(12C)=40MeV is presented to demonstrate the capability of the neutron detector array.2Description of Neutron Detector ArrayThe neutron detector array consists of16plastic scintillator bars(equiva-lent to Bicron BC-408and procured from SCIONIX,Holland)of square crossFig.1.A photograph of the plastic scintillator detector array taken with15bars. section[4].Each bar has a dimension6cm×6cm×100cm and is coupled to two5cm diameter XP2020PMTs,one each at either end.The scintillator has a light output of∼65%compared to that of anthracene,a scintillation decay time of∼4ns and a bulk attenuation length>3m.The polyvinyl toluene based plastic scintillator has a carbon to hydrogen ratio of∼1:1.1.The density and refractive index of the scintillator are1.03gm/cm3and1.58,respectively. The spectral sensitivity of the XP2020PMT peaks at420nm,with a quan-tum efficiency of∼25%,and matches the emission spectrum of the plastic scintillator.The PMTs have a fast response time(rise time∼1.3ns)and a gain of∼107at about2kV bias voltage.The PMTs are powered by a32 channel programmable high voltage power supply developed in-house[5].The plastic scintillators are stacked one above the other on a stand with wheels for horizontal movement of the array and a four bolt arrangement to adjust the height and level.A photograph of the array is shown in Fig.1.of the target.Q L lnThe efficiencies of the plastic scintillator for the two neutron energy groups mentioned above were estimated as follows.In the data analysis the num-ber(M)of BaF2detectors detecting the429keVγ-ray in coincidence was generated event by event.The events with M>1obviously correspond to ran-dom events.The yield of the n1group at each proton energy was obtained from the TOF spectra for the condition of M=1and E ee≥250keV.The neu-tron detection efficiencies were obtained from these yields,the target thickness and the angle dependent cross section of the n1group.This cross section was taken from Poppe et al.[7].The target thickness was obtained from the sin-glesγ-yield in all seven BaF2detectors measured at16MeV proton energy. The efficiency of the BaF2array for429keVγ-rays was calculated as26.7% using the Electron Gamma Shower(EGS)simulation program[8].The target thickness extracted using the angle integrated cross section from Ref.[7]was 2.8±0.3mg/cm2.The neutron detection efficiencies estimated from the above procedure were divided by the geometrical efficiency of the detector to get the intrinsic efficiencies.These are shown in Table1.These measured efficiencies, however,include the contributions of the scattered neutrons from the BaF2 array.This effect was estimated to be<7%from the Monte Carlo simulation discussed in the next section.4Monte Carlo simulation of the neutron detector arrayThe simulation of the response of the plastic detector array to fast neutrons has been performed by a Monte Carlo program developed in our laboratory. The processes by which neutrons of energy up to∼20MeV interact with the detector material were taken as(a)elastic scattering on hydrogen and12C,Measured and simulated intrinsic efficiency of plastic scintillator detector for mono-energetic neutrons in the absence(A)and presence(B)of the BaF2array.E n(MeV)Simulatedefficiency(%)efficiency(%)(B)27.4±2.827.222.7±3.222.3(b)inelastic scattering to the4.4and7.6MeV states in12C and(c)12C(n,α), 12C(n,p)reactions.Among these thefirst process is the dominant one.The cross sections were taken from Ref.[9].In the program,neutrons of a given energy are made incident on the plastic array,placed at a certain distance from the source,assuming angular isotropy. The energy dependent total interaction cross section determines whether the neutron scores a hit in the detector.If it scores a hit,the interaction process is chosen randomly on the basis of the relative magnitude of the respective cross section.If the process is elastic scattering on hydrogen,the scattering angle in the centre of mass(c.m.)system is chosen randomly.This decides the energy of the recoiling proton which is assumed to be fully deposited in the detector. In(n,p),(n,α)and(n,n′)3αprocesses,the energy of p andαwere calculated assuming isotropic emission in the c.m.system.For the(n,n′γ)process,the 4.4MeVγ-ray deposits energy depending on the attenuation length and the available path in the scintillator for a given propagation direction.The electron energy equivalent(E ee)of the deposited energy for heavy charged particles areParameters in the light response function for proton and alpha.Particles a2a40.970.1Alpha 5.9 1.01obtained using the following empirical expressionT e=a1T p−a2[1.0−exp(−a3T p a4)].(5)The choice of the parameters a1to a4was guided by those given by Cecil et al.[9]with somefine tuning.These are presented in Table2.The light output due to recoiling12C nuclei is small and therefore neglected.The time of occurrence of the PMT signal was derived from the neutronflight times and the scintillation photon propagation time.The simulated left and right PMT times(T L,T R)and E ee from each event were used to generate TOF and E ee spectra provided E ee is greater than the experimental threshold.The TOF spectrum for a given neutron energy shows a peak with a width arising from the intrinsic time resolution of the plastic scintillator as well as the variation in the interaction position.The shapes of the simulated E ee spectra at neutron energies of7.1and12.7MeV compare well with the experiment as shown in Fig.11.The ratio of detected events to the number of incident neutrons gives the intrinsic neutron efficiency.The simulated intrinsic efficiencies of one plastic scintillator for neutrons of energies7.1and12.7MeV were obtained for the experimental threshold(E ee)of250keV.These are shown in the third column of Table1.The energy dependent neutron efficiencies for various thresholds areshown in Fig.12for a single plastic scintillator with the lead shield in front. It can be seen that while an increase in E ee does not substantially change the neutron detection efficiency at higher energies,it increases the effective threshold energy for neutron detection.The presence of the BaF2array near the target is a source of scattered neu-trons,some of which reach the plastic detector.In order to estimate their con-tribution to the measured efficiencies,the simulation program was extended to include the elastic and non-elastic processes from Ba and F in BaF2.The increase in the TOF of the elastically scattered neutrons is too small to distin-guish from that of the neutrons directly reaching the plastic.The non-elastic processes lead either to a loss of neutrons as in the(n,p),(n,α),(n,γ)reac-tions or to a low energy neutrons from the(n,n′)and(n,2n)reactions.These processes,therefore,do not contribute to the counts in the TOF peak.The in-trinsic efficiencies in the presence of BaF2are renormalised by the extra contri-bution in the TOF peak essentially due to elastic scattering.These are shown in the last column of Table1.The renormalised efficiencies are increased by <7%.These are however the upper limits because we have assumed isotropy in the scattering processes whereas the limited elastic scattering data shows forward peaked distribution(see for example Ref.[10]).It may be mentioned that the elastic scattering process on BaF2does not lead to any significant change in energy spectrum shown in Fig.11.the timing signal.The CFD thresholds were set at∼100keV.One of the CFD outputs was sent to the corresponding start channel of the time to digital converter(TDC)filtered through the condition that at least one of the BGO detectorsfire.The second CFD output was used to generate the QDC gate.The third output was used to define a valid event by combining signals from all the scintillators in a logic OR unit.This OR output(Plastic-OR)was used for the common QDC gate.The timing signals from the BGO detectors were time matched and sent to a multiplicity logic unit(MLU)[11].The time matched OR-output(BGO-OR) was used tofilter the plastic CFD signals as mentioned above.A coincidence between the BGO-OR and the Plastic-OR was used tofilter the RF signal derived from the beam pulsing system.Thefiltered RF was used as the com-mon stop for all the TDC channels.The left and right times of each plastic scintillator were measured with respect to thefiltered RF.In addition,the integrated charges(Q L,Q R),number of BGO detectorsfiring simultaneously (fold)and the RF-BGO time were recorded in an event by event mode.The time and energy calibrations were done as mentioned earlier.In the offline analysis,the TOF was derived from T L and T R.The zero of the time scale was determined from the prompt gamma peak in the TOF spectrum.The position information was obtained from the difference between the left and right time.Four position gates were decided by inspecting the position spec-tra.A TOF spectrum for a typical plastic scintillator with position gating on a quarter of its length and at least one BGO in coincidence is shown in Fig.15.The random background reduces drastically with the BGO coinci-dence requirement allowing the measurement of neutrons with low production cross section.The fold gated neutron time offlight spectra,after subtracting the random background for each position cut,were converted to energy spec-tra.The energy dependent efficiencies of the neutron detectors of the array for different position gates were calculated using the Monte Carlo simulation program mentioned earlier.The energy threshold used in the simulation was1)the uncertainty in fusion cross section used in the SMCC calculation and2)the presence of low energy electromagnetic transitions in the residues which are detected with poor efficiency and,hence,affect the J res to M prescription used in the calculation.6SummaryIn summary,we have set up a1×1m2plastic detector array for neutron time of flight measurements at the BARC-TIFR Pelletron laboratory.We have mea-sured the response of the detector to electrons using radioactive sources and mono-energetic neutrons using the7Li(p,n1)reaction.A Monte Carlo simula-tion program has been developed to simulate the response of the detector for neutrons and is in agreement with our measurements.The detector array was used to measure the energy differential neutron cross sections in the reaction 12C+93Nb at E(12C)=40MeV in coincidence with a14-BGO gamma mul-tiplicity array.The measured spectral shape is in reasonable agreement with a statistical model calculation.AcknowledgementsWe thank the Pelletron stafffor accelerator operation,Mechanical Design and Prototype Development Section,BARC,for fabricating the mechanical stand and the lead shield and H.H.Oza and M.S.Pose for their help during the experiment.We would also like to thank the anonymous referee for his critical comments.References[1] A.Mitra et al.,Nucl.Phys.A765(2006)277;ibid A707(2002)343.[2] A.Mitra et al.,Proc.DAE-BRNS 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