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TRITON X-100Product Number X-100, T9284, T8787, T8532 Storage Temperature 25°CCAS #: 9002-93-1Synonyms: X-100; TRITON X-1001; Octylphenol ethylene oxide condensate 1Product DescriptionAppearance: Liquid, clear to slightly hazy, colorless to light yellowSpecific gravity: 1.065 at 25°C (approx. 1.07 g/mL)1 Approximate Molecular Weight: 6251;effective molarity =1.7 M for the neat liquid.1UV absorption: λmax = 275 nm (E 1% = 23.9) and 283 nm (E 1% = 19.4) in methanol 2Typical values:Viscosity (Brookfield): 240 cps at 25°C 1Cloud point (1% aqueous solution): 63-69°C 1 Pour point: 7°C 1pH (5% aqueous solution): 6.0 to 8.01 Calculated HLB value: 13.51Critical micelle concentration (CMC): 0.22 to 0.24 mM 3,4The structure of Triton X-100 is very similar to that of Igepal CA-630 (Sigma I3021) and of Nonidet P-40 (no longer commercially available); the names aresometimes reported as synonyms.5 However, Triton X-100 is slightly more hydrophilic than Igepal CA-630. The two are not considered to be functionally interchangeable in most applications.Triton X-100 is a nonionic detergent, 100% active ingredient, which is often used in biochemicalapplications to solubilize proteins. Triton X-100 has no antimicrobial properties.1 It is considered acomparatively mild non-denaturing detergent and isreported in numerous references. It does absorb in the ultraviolet region of the spectrum, so it can interfere with protein quantitation by absorption at A 280nm . A number of polymeric resins have been used to remove X-100 from solution, including Amberlite hydrophobic XAD resins 6 and Rezorian A161 cartridges.3The "Triton X" series of detergents are produced from octylphenol polymerized with ethylene oxide. Thenumber ("-100") relates only indirectly to the number of ethylene oxide units in the structure. X-100 has an"average of 9.5" ethylene oxide units per molecule, with an average molecular weight of 625.1,3 In addition, lower and higher mole adducts will be present in lesser amounts, varying slightly within supplier's standard manufacturing conditions. A by-product formed during the reaction is polyethylene glycol, a homopolymer of ethylene oxide. Acid is also added to the product to neutralize the product after the base catalyzed reaction is completed. No antioxidants are added by Sigma or the manufacturer, but commercial preparations of Triton X-100 have been found to contain peroxides up to 0.22% hydrogen peroxide (H 2O 2) equivalents,7 which may interfere with biological reactions. Sigma offers X-100-PC and X-100R-PC as alternatives. TritonX-100 absorbs in the UV spectrum at approximately the same wavelength as proteins (280 nm). Sigma offers two "reduced", i.e., hydrogenated forms, X-100-RS and X-100R-PC that have significantly lower absorbance in this region.4For lysing cells, typically about 0.1% X-100 solution in water will be sufficient, and even up to 0.5%concentrations will usually not harm most enzymes being isolated.3 Many enzymes remain active in the presence of X-100; for example, Proteinase K, remains active in 1% (w/w) solutions of X-100.8Triton X-100 can be detected in the parts per million range by spectrophotometric measurement of theconcentration of a Triton-ammonium-cobalt-thiocyanate complex.9 Interfering substances in this assay have been discussed.15(OCH 2CH 2)x OHCCH 2C H 3C CH 3CH 3CH 3CH 3x = 9-10For a given application, the choice of a suitable surfactant depends on a number of variables, from its solubility, polarity and micelle size to the mechanism of its action with the target solute. The literature contains numerous articles:10-13!Choice of detergent for solubilization of(erythrocyte) membranes10!Effect of hydrophile-lipophile balance on(cytochrome) membrane solubilization11!Mode of interaction of polyoxyethylene glycol detergents with membrane protein12!General background on surfactants and use in protein purification13Preparation InstructionsTriton X-100 is soluble in all proportions at 25°C in water, benzene, toluene, xylene, trichloroethylene, ethylene glycol, ethyl ether, ethanol, isopropanol, and ethylene dichloride.1 At 10% (v/v) in water, it gives a clear to slightly hazy solution, from clear to slightly yellow in appearance.3Solutions are stable to autoclaving. At certain concentrations the solutions may be cloudy but dispersible above the cloud point; they should clear with stirring upon cooling.14Storage/StabilityTriton X-100 is considered stable for years if stored sealed at room temperature. For special applications, storage under argon or nitrogen at 2-8°C may be preferred. References1. Supplier data (Triton X-100 is a product of UnionCarbide.)2. Wexler, A.S., Anal. Chem., 35, 1936-1943 (1963).3. Sigma data.4. Tiller, G.E. et al., Anal. Biochem., 141, 262 (1984).5. The Merck Index, 11th ed., #6681 (1989).6. Holloway, P.W., Anal. Biochem., 53, 304 (1973).7. Ashani, Y. and Catrovas, G.N., Anal. Biochem.,109, 55-62 (1980).8. Enzymes of Molecular Biology, M.M. Burrell, Ed.(Humana Press, NJ, 1993), p. 307.9. Supplier method, based on work by Crabb, N.T.and Persinger, H.E., J. Amer. Oil Chem. Soc., 41,752-755 (1964) and Greff, R.A. et al., J. Amer. Oil Chem. Soc., 42, 180-185 (1965).10. Grant, D.A. and Hjerten, S., Biochem. J., 164, 465-468 (1977).11. Slinde, E. and Flatmark, T., Biochem. Biophys.Acta, 455, 796-508 (1976).12. Le Maire, M. et al., Eur. J. Biochem., 129, 525-532(1983).13. Methods in Enzymology, 182, 239-282 (1990):reviews by Neugebauer, J.M., Hjelmeland, L.M.,etc.14. Supplier information.15. Goldstein, S. & Blecher, M., Anal. Biochem., 64,130-135, (1975).ckv 4/21/99Sigma brand products are sold through Sigma-Aldrich, Inc.Sigma-Aldrich, Inc. warrants that its products conform to the information contained in this and other Sigma-Aldrich publications. Purchaser must determine the suitability of the product(s) for their particular use. Additional terms and conditions may apply. Please see reverse side ofthe invoice or packing slip.。
I M o t o w w w .e x t r o n .c , i n st a l l a t i o n i n s t r u o r e c o n n e c t i n g t h eu r ce .XTRA ™(XPA 1002, XPA 1002 Plus, XPA 1002-70V , XPA 1002-100V , XPA 2001-70V, XPA 2001-100V)This guide provides startup instructions for experienced, professional installers to set up and operate the XPA 1002 or XPA 2001 series audio power amplifiers. All references are to the XTRA Series Half-Rack user guide which can be found on .Step 1 — Powering Down EquipmentBe sure that power to the amplifier is turned off first.Turn off all other equipment and disconnect the power cables. Verify that the amplifier is disconnected from the power source before proceeding.Step 2 — Mounting and ApplicationsFor diagrams of typical application examples, see Application Examplesin the user guide. For further mounting instructions, see Mounting the XTRA Series Amplifier in the user guide.Step 3 — Captive Screw Audio Cable WiringWire the source output to the amplifier input 3.5 mm captive screw connectors as shown in the following illustration.XPA 1002, XPA 1002 Plus XPA 1002-70V/100VUnbalanced Dual Mono Input XPA 1002, XPA 1002 Plus XPA 1002-70V/100VBalanced Dual Mono InputUnbalanced Stereo Input Balanced Stereo InputStep 4 — Speaker WiringWire the speakers to the output connector of the amplifier using the included 4 pole (XPA 1002, XPA 1002 Plus, XPA 1002-70V/100V) or 2 pole (XPA 2001-70V/100V) captive screw connector as shown to the right.XPA 1002,XPA 1002 Plus XPA 1002-70V/100VXPA 2001 Series68-2354-50 Rev. C02 16Extron Headquarters+1.800.633.9876 (Inside USA/Canada Only)Extron USA - West Extron USA - East +1.714.491.1500 +1.919.850.1000 +1.714.491.1517 FAX +1.919.850.1001 FAXExtron Europe+800.3987.6673(Inside Europe Only)+31.33.453.4040 +31.33.453.4050 FAXExtron Asia+65.6383.4400+65.6383.4664 FAXExtron Japan+81.3.3511.7655+81.3.3511.7656 FAX Extron China+86.21.3760.1568 +86.21.3760.1566 FAXExtron Middle East+971.4.299.1800+971.4.299.1880 FAXExtron Australia+61.8.8351.2188+61.8.8351.2511 FAXExtron India1800.3070.3777 (Inside India Only)+91.80.3055.3777 +91.80.3055.3737 FAX© 2016 Extron Electronics All rights reserved. Step 5 — Setting the High Pass Filter (HPF)On XPA 1002-70V/100V and XPA 2001-70V/100V models, use a Tweeker to toggle the high pass filter switch between off (no filtering) and 80 Hz (default). Setting the switch to 80 Hz prevents the saturation of speaker input transformers by low frequency signals.Step 6 — Control WiringOn the XPA 1002, XPA 1002 Plus, XPA 2001-70V , and the XPA 2001-100V models, the 3.5 mm 5-pin captive screw remote control port (shown to the right) is used to control volume and standby mode through contact closure.Standby mode turns off all output, although the XPA is still receiving power. For detailed wiring instructions, see the user guide.On the XPA 1002-70V and XPA 1002-100V models, the 3.5 mm 2-pin captive screw remote control port (shown to the right) controls the standby mode only.Step 7 — Powering On EquipmentReconnect all power cables and switch on all other equipment before powering on the power amplifier. The front panel power LED of the amplifier lights green.Step 8 — Adjusting Attenuation Adjust the audio attenuation using the rear panel adjustment potentiometers as shown below (see Rear Panel Features and Operation in the user guide for more information).XPA 1002 Series XPA 2001 SeriesLEVEL 12LEVELXPA 1002XPA 2001 SeriesStep 9 — Checking the LEDsCheck the limiter/protect and signal LEDs located on the front and rear panels if problems are encountered (see Rear Panel Features and Operation in the user guide for more information).or80 HzHPFOFF。
尾数问题例i: 积的尾数是几？分析与解：我们先来计算几种简单的情况，看看积的尾数有什么样的规律：3个位数子是:3,3X 3=9积的尾数是9,3X 3X 3=27积的尾数是7,3X 3X 3X 3= 81积的尾数是1,3X 3X 3X 3X 3=243积的尾数是3,3X 3X 3X 3X 3X 3=729积的尾数是9,3X 3X 3X 3X 3X 3X 3=2187积的尾数是7,3X 3X 3X 3X 3X 3X 3X3=6561积的尾数是1通过上面的计算，我们便可以发现尾数是按3, 9,乙1, 3, 9, 7, 1,……的规律不断依次重复出现的。
2005+ 4=501……1,可知积的尾数是3。
例2: 积的个位数是几？分析与解：积的个位数与©呑蔦二［…°积的个位数相同。
个位是6。
xg PN ........................... ..................... ....例3: 「积的尾数是几?<>2 .■- 9N …… SN Z 宀2 - 2 尸……” N分析与解：〜—~积的尾数与— ~2OCM-1^2 *积的尾数相同。
2,2X 2,2X 2X 2,2X 2X 2X2,2X 2X 2X2X 2,2X 2X 2X2X 2X 2,2X 2X 2X2X 2X 2X2,2X 2X 2X2X 2X 2X2X2,积的尾数分别是2, 4, 8, 6, 2, 4, 8, 6,…….......... y2004+ 4=501，可知聘三'的尾数是6,3N x x 92 ..................... ... 3N即' 的尾数是6。
例4: 8+88+888+8888+••…+耳482…438和的末三位数是多少？2005 个8分析与解一：个位上有2005个8相加，和是16040,和的个位写0, 向十位，进1604；十位上有2004个8相加，再加上进位的1604,和是17636,和的十位写6,向百位进1763；百位上有2003个8相加，再加上进位的1763,和是17787,和的百位写乙向千位进1778。
静伏暗出 一出即胜VICTOR ARS-100X重返球场今年，VICTOR献上神速系列全新战拍ARS-100X。
尾缀为「X」带有全面特性的旗舰速度拍，衔接平抽快挡与高速进攻之间的连贯性。
ARS-100X集结神速系列的技术特点。
在外观上导入透明前套以及透明后套，让消费者一窥新科技POWER RING 力量环以及FREE CORE悬浮核心科技的奥秘，同时创造ARS-100X锋芒暗藏的犀利性格。
它也被「世界冠军」阿山选用为新赛季战拍。
整体配置上，ARS-100X承袭神速系列经典的DYNAMIC-SWORD动力破风框型，并使用SRS高弹转生中管科技，使中管根基再加固，加速中管恢复力，提供进攻连贯性。
与此同时，搭载FREE CORE悬浮核心科技及POWER RING力量环，手感顺畅，刚柔并济，力量瞬发集中，一出即胜。
ARS-100X适合连贯精准突击或者主打控制、擅长变换球路的选手。
流畅破风·攻控连贯动力破风框+弹力盾弹力盾科技将高强韧玻璃纤维导入动力破风框拍框叠层设Copyright©博看网. All Rights Reserved.110 March 2022计，使击球时达成更佳的弹性与舒适手感。
经典动力破风框结合弹力盾加强技术发酵出流畅破风效果，实战中的平抽挡及连贯进攻都更加稳定精准，带来连续压迫的强劲攻势。
中管再创新·力量瞬发集中高弹转生中管（S.R.S）对于羽毛球拍中管技术的研制精进，VICTOR从未停下脚步。
全新Shaft Recovery System 高弹转生中管科技，以高T 数材料增强中管恢复效果，进一步激发中管弹性潜能，中管根基加固，带来更快的中管回弹效果，力量瞬发集中。
手柄强化·释放扎实打感FREE CORE悬浮核心科技+POWER RING力量环。
耳机的试用报告台湾SpearX声特MH-100耳机试用报告国粹精品——台湾SpearX MH-100耳机试用报告测试耳机：MH-100测试前端：HM603 ROCOO-P PC对比耳机：HD25amperior K450 HD598 MX400昨天刚收到包裹时候看到了精致的MH100躺在盒子里，说实话我的初步预算是这耳机和K450便携出街流持平就可以，所以也没有多少期待的感觉。
唯一令我感兴趣的就是终于有敢专门对高档头戴耳机下手的国产公司了。
小尺寸封闭式耳机大多都为了出街设计，因此价位并不高，调音容易趋向中下盘，我想是为了迎合更多普通消费者而不是发烧友那挑剔的耳朵。
毕竟这个价位单元硬素质摆在这里，低频做多了，外加收不回去，一挤就会出现发闷的感觉。
我是抱着这个心态去进行的试听的。
先说佩戴，刚拿到手看到如此小的耳罩我就晕了，这是要夹耳朵的节奏啊。
结果佩戴了一个多小时也没有夹耳朵的感觉。
这点做的真好。
可能是耳罩选材好的缘故。
结果刚开声就把我吓到了。
MH-100耳机的声场比我预期的大了好几圈，低频也拳拳到肉，最值得夸耀的就是那种在这个价位上变态的解析能力。
感觉直接就能把K450秒了。
可能是突如其来的惊喜冲昏了头脑，接下来一晚上听到的都是好声音。
我决定初步煲一煲，第二天再冷静下来写点东西。
20小时的磨合，耳机已经崭露了它的初步特点，在这里有好有坏。
我都一一点明。
700这个价位，SpearX声学选择了耳机取向中下盘以迎合更多人的耳朵，这点和我预料的一样，不过没猜到的是耳机并不很闷，这是由于声场不狭窄的缘故。
这种低端价位上，人声也非常有感情。
要说耳机的强处，那莫过于变态的解析力了。
这么高的解析在这个价位的耳机中还真少见。
可能是我听得不多的缘故。
但是我觉得足够和我常听的HD25与未上放的HD598有的一拼。
这么小的玩意包围感却非常厉害，加州旅馆的临场感十足，耳机声底非常干净，我觉得它应该是一个听乐器的耳机。
低频也是耳机的强处，渡口的定音鼓直接敲到胸口的感觉。
哈佛智商测试题及答案1. 问题：一个数字序列是 2, 4, 8, 16, 32, 64, 接下来是什么数字？答案：128。
这个序列是每个数字乘以2得到的。
2. 问题：如果所有的男人都是红色的，所有的女人都是蓝色的，那么一个红色的爸爸和一个蓝色的妈妈会生出什么颜色的孩子？答案：红色。
因为爸爸是红色的，孩子会继承父亲的性别特征。
3. 问题：一个房间里有三盏灯，外面有三个开关，每个开关控制一盏灯。
如果只能进入房间一次，如何确定哪个开关控制哪盏灯？答案：首先打开第一个开关，等待足够的时间（例如5分钟），然后关闭它。
接着打开第二个开关，然后立即进入房间。
此时，亮着的灯是由第二个开关控制的。
如果是热的但没亮的灯，是由第一个开关控制的。
剩下的一盏灯则是由第三个开关控制的。
4. 问题：有五个海盗，他们按照年龄从大到小排列，最年长的海盗有权决定如何分配100枚金币。
如果他们不同意分配方案，他们将投票决定是否杀死提出方案的人。
每个海盗都希望尽可能多地获得金币，并且都希望生存。
最年长的海盗应该提出怎样的分配方案，以确保自己获得最大利益？答案：最年长的海盗应该提出自己获得全部100枚金币，不给其他海盗任何金币。
这是因为在这种策略博弈中，最年长的海盗可以通过威胁其他海盗的生命来确保自己的利益最大化。
5. 问题：一个钟的时针和分针在一天内会重合多少次？答案：22次。
在一天内，除了12点整，时针和分针会在每个小时重合一次，但由于12点整时它们已经重合，所以一天内总共会有22次重合。
6. 问题：一个农场主有一块土地，他想将其分成7块相等的正方形土地。
如果这块土地是一个矩形，他需要多少篱笆？答案：如果这块土地是一个7x1的矩形，那么他需要16段篱笆。
因为每块正方形土地的边长是1，所以7块正方形土地排成一行，需要7段篱笆来分隔它们，再加上两端各需要4段篱笆，总共需要16段篱笆。
7. 问题：一个数字去掉最后一位是40，去掉第一位是13，这个数字是什么？答案：413。
在新托福阅读的考查中，每篇文章必会出现一类题，叫做"Insert Text Questions"，即插入句子题(简称插入题)。
考试中，考生会遇到一句话，问该句插入文中哪里最合适。
如下面例题：▇The raising of livestock is a major economic activity in semiarid lands, where grasses are general the dominant type of natural vegetation. ▇The consequences of an excessive number of livestock grazing in an area are the reduction of the vegetation cover and the trampling and pulverization of the soil.▇ This is usually followed by the drying of the soil and accelerated erosion. ▇Look at the four squares ▇ that indicate where the following sentence can be added to the passage。
This economic reliance on livestock in certain regions makes large tracts of land susceptible to overgrazing。
Where would the sentence best fit?(选自Official Guide P73)按照ETS官方指南上的解析，这类题型重点考查英文句子间的逻辑语义关系，即英文中句子与句子是如何衔接在一起的。
所以，只要掌握了英语句子间的衔接手法(cohesive devices)，这种问题便可迎刃而解。
那么，英文句子有哪些衔接手法呢？主要分为以下四种。
1. 代词(Pronouns)具体包括人称代词、指示代词和关系代词等(personal, demonstrative, relative, etc)。
在上下句的关联中，代词是最为紧密的一类词。
当作者再次谈及上句相关话题时，为了避免重复，遵循语言学的最简单化原理，作者会用代词指代该话题词。
例如，Speaking a foreign language is an enormous asset in the modern world. This is why so many junior high schools are now offering language classes。
Today's teachers are faced with a stark choice. They must decide whether to teach in a way that helps student pass standardized exams or teach in a way that actually helps students learn。
2. 定冠词the + 名词(specific articles+nouns)名词所指对象第一次出现时，用不定冠词a连接，当后句再次提及该名词对象时，为了表示它和前一句名词是同一关系，会用定冠词the引出。
例如，A woman is walking into our classroom. The woman is our teacher。
3. 重复话题词或同义近义改写(Repetition, synonym, or slight variation of a word)上下句的衔接也可以通过重复话题词实现，或者是对该话题词进行相关改写。
例如，To foster healthy relationships between children in a classroom, teachers should provide time for games and fun activities. Having healthy relationships with their peers helps children gain confidence useful in other parts of their lives. (重复话题词)Before choosing a public or private school for their children, parents should take into account the cost. The price of a private school is usually much higher than that of a public school. (话题词同义改写)4. 过渡性词和词组(Transitional phrases/transitional adverbs)上面讲到的三种句间关系属于隐性关系。
隐性关系通过上下句的语义关系体现。
现在，我们要讲的是句子间的显性关系，即通过明显的逻辑连词或副词来体现句间关系。
这些显性关系词包括以下类别。
4.1 时间关系then, next, later, finally, etc。
4.2 因果关系therefore, consequently, as a result, etc。
4.3 转折关系however, but, yet, nevertheless, on the other hand, etc。
4.4 解释关系that is, in other words, etc。
4.5 举例关系for instance, for example例如，Peers and older siblings have a major influence on how school children behave. For instance, young children often repeat bad words they hear from their friends or brothers and sisters。
有了上面的理论铺垫，我们再来看小插题就容易得多了！例如，前面给出的那道例题，▇The raising of livestock is a major economic activity in semiarid lands, where grasses are general the dominant type of natural vegetation. ▇The consequences of an excessive number of livestock grazingin an area are the reduction of the vegetation cover and the trampling and pulverization of the soil.▇ This is usually followed by the drying of the soil and accelerated erosion. ▇Look at the four squares ▇ that indicate where the following sentence can be added to the passage。
This economic reliance on livestock in certain regions makes large tracts of land susceptible to overgrazing。
Where would the sentence best fit?我们先读给出的这句话--This economic reliance on livestock in certain regions makes large tracts of land susceptible to overgrazing. 这个句子使用的衔接手法(cohesive device)属于代词指代前文话题词。
this 后面的名词economic reliance on livestock一定在上一句里出现。
于是，搜索段落，答案锁定在第二个方框前的那一句The raising of livestock is a major economic activity in semiarid lands, where grasses are general the dominant type of natural vegetation。
这句话与被插入的句子话题一致，都是在讲"经济上依赖牲口"这件事，所以应插入第二个方框。
同理，以下考题，请考生自测。
答案见文末。
Extinct but already fully marine cetaceans are known from the fossil record. ▇How was the gap between a walking mammal and a swimming whale bridged? ▇Missing until recently were fossils clearly intermediate, or transitional, between land mammals and cetaceans。
▇Very exciting discoveries have finally allowed scientists to reconstruct the most likely origins of cetaceans. ▇ In 1979, a team looking for fossils in northern Pakistan found what proved to be the oldest fossils whale。
Look at the four squares ▇ that indicate where the following sentence can be added to the passage。
This is a question that has puzzled scientists for ages。
Where would the sentence best fit?(选自Official Guide P64)Paragraph 3: ■Exhibitors, however, wanted to maximize their profits, which they could do more readily by projecting a handful of films to hundreds of customers at a time (rather than one at a time) and by charging 25 to 50 cents admission. ■About a year after the opening of the first Kinetoscope parlor in 1894, showmen such as Louis and Auguste Lumiere, Thomas Armat and Charles Francis Jenkins, and Orville and Woodville Latham (with the assistance of Edison's former assistant, William Dickson) perfected projection devices. ■These early projection devices were used in vaudeville theaters, legitimate theaters, local town halls, makeshift storefront theaters, fairgrounds, and amusement parks to show films to a mass audience.■Look at the four squares [■] that indicate where the following sentence can be added to the passage。
