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    E A. A great drain on energy B. Expensive transportation C. Extra cost D. Market history E. Making a profit F. Demand for the water 80． The cost of transporting water is determined largely by how far it has to be carried and how high it has to be lifted. Growing cities and towns may have to go hundreds of kilometers to find the water needed to satisfy their increasing thirst. California cities have long imported water from hundreds of kilometers away. And China is constructing three canals that are 1,156 kilometers, 1,267 kilometers, and 260 kilometers long to transfer water from the Yangtze River to Beijing and other rapidly growing areas in the northern provinces. 81． Pumping water out of the ground or over land to higher elevations is energy-intensive. Pumping 480 cubic meters of water a height of 100 meters requires some 200 kilowatt-hours of electricity. At a price of 10¢ per kilowatt-hour, the cost is $20-not including the cost of the pump, the well, and the piping. One hundred meters is not an unusual lift for wells tapping falling supplies of groundwater. In Beijing and other areas in northern China, for instance, lifts of 1,000 meters are sometimes required. 82． In most places water is not purchased or exchanged in a market. But formal water markets are developing in the western United States, Australia, and Chile. Where these water markets do exist, they provide examples of how high the scarcity value of the water-that is, the amount that other potential users would be willing to pay for it-can be. Water prices in Australia’s markets peaked at near 75¢ per cubic meter in December 2006, climbing 20-fold in a year in part due to prolonged drought. In the U.S. West, water prices typically range between 3 cents and 10 cents per cubic meter. 83． In India, water scarcity has prompted some farmers to profit by selling their water instead of farming. The water they formerly used to irrigate their crops is instead pumped from their wells and trucked to nearby cities. The farmers are harvesting water rather than food and at the same time promoting a rapid drop in underground water tables. 84． Another factor affecting how much people pay for water is the amount it is subsidized . Water subsidies can be very large. For instance, water revenues in the city of Delhi are less than 20 percent of what it spends each year to provide water. On average worldwide, nearly 40 percent of municipal suppliers do not charge enough for water to meet their basic operation and maintenance costs. 第Ⅱ卷 【查看更多】

     

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    阅读下面两个材料并回答问题：
    【材料一】2011年10月3日，诺贝尔奖委员会宣布，美国科学家布鲁斯·巴特勒、卢森堡科学家朱尔斯·霍夫曼和加拿大科学家拉尔夫·斯坦曼获得2011年诺贝尔医学生理学奖。在长期进化过程中人体具备两种免疫机能：一是“固有免疫”，二是“获得性免疫”。布鲁斯·巴特勒、朱尔斯·霍夫曼的获奖领域在前者；而拉尔夫·斯坦曼的工作主要在后者。
    布鲁斯·巴特勒、朱尔斯·霍夫曼发现了由“Toll”基因编码的关键受体蛋白，该受体蛋白能识别病原微生物，并激活“固有免疫”，打开免疫反应的第一步；拉尔夫·斯坦曼发现的树突状细胞在免疫应答中作用，树突状细胞在体内游弋，发现并摄取病原体的特异性抗原，并报告给T淋巴细胞，T细胞将调动其他免疫细胞发生级联反应，最终消灭病原体。
    （1）材料中所描述的“固有免疫”就是_____________________免疫，这种免疫对所有的病原体都有防御作用。（1分）
    （2）下列有关“Toll”基因的叙述正确的是：_____________（单选）（1分）
    A．Toll基因只存在于免疫细胞中
    B．Toll基因编码受体蛋白，体现基因对性状的直接控制
    C．Toll基因编码的受体蛋白能识别病原微生物，体现了免疫细胞的特异性识别
    D．效应T细胞能与靶细胞密切接触就是该受体功能体现
    （3）下列有关树突状细胞的叙述正确的是：_____________________（不定项）
    A．树突状细胞在免疫中发挥作用，说明神经系统与免疫系统功能密切相关
    B．在细胞免疫和体液免疫中树突状细胞所起的作用没有明显差别
    C．树突状细胞能够处理和呈递病原体的抗原特异性
    D．树突状细胞可触发T细胞发生免疫反应
    E．树突状细胞可能是一种吞噬细胞
    【材料二】（根据南方周末《乔布斯的错误与诺奖得主的试验》整理）就在瑞典卡罗琳医学院宣布本年度诺贝尔医学奖的前3天，斯坦曼因胰腺癌不幸离世，他没能亲耳听到自己获奖的喜讯，令人惋惜。就在他离世死后的第6天“改变世界”的IT精英乔布斯也因胰腺癌英年早逝。
    两人所患的胰腺癌都是死亡率极高的恶性肿瘤。乔布斯患的是“胰腺内分泌型肿瘤”，该病症病情发展缓慢，能存活数年的患者不在少数。但这位著名的素食主义者曾一度拒绝手术治疗，导致肿瘤细胞转移，病情迅速恶化。
    而斯坦曼所患的病症为“胰腺外分泌型肿瘤”，该病患者的存活期往往只有数月。斯坦曼在2007年确诊胰腺癌后，就积极尝试基于树突状细胞的治疗性疫苗(DC疫苗)。借助这种“细胞免疫疗法”，他的生命从预期的数月延长至4年。
    （4）乔布斯癌变的细胞可能是_____________细胞，该细胞的分泌物与_________________。系统消灭癌细胞的过程是_____________（填一种特异性免疫）发挥作用。
    （5）斯坦曼所注射的DC疫苗是由其体内的树突状细胞和肿瘤细胞中提取的一种短肽（即治疗性疫苗），该短肽在免疫中作为_____________引起人体发生免疫反应。除树突状细胞外，斯坦曼体能够特异性识别这种短肽的细胞还有（至少写出3种）______________________________________。
    （6）有人认为DC疫苗对防治癌症有一定的疗效，原因是：通过免疫反应斯坦曼体内的免疫系统产生抗体，抗体与该短肽特异性结合，使短肽失效。你认为这个解释对吗，____________，请说出你的理由：_________________________。（共2分）
    （7）斯坦曼生前尝试注射过三种DC疫苗，却还是未能逃出死神的魔掌，请从免疫学的角度分析导致他死亡的可能原因是：________________________________________。

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    假如你是Li Lei, 下面是一封你的笔友Maria 给你发来的e-mail,请你根据e-mail 的内容给她写一封回信，与她交流看法，并帮她排忧解难。
    　　提示词语：listen to, mother’s love, care about, communicate with, get along with, smile
    写作要求：
    （1）语句通顺，书写工整；
    （2）可用所给提示词语，也可以适当发挥；
    （3）词数在60—80词左右
    Dear Li Lei,
    　　I’m afraid I’ve got a big problem recently. My mother talks too much to me. She always tells me, "Be careful while crossing the street." "Put on more clothes." "Did you do a good job at school?" and so on. I’m annoyed(烦恼)。What shall I do?  
    Yours,
    Maria
    _______________________________________________________________________________
    _______________________________________________________________________________
    _______________________________________________________________________________
    _______________________________________________________________________________
    _______________________________________________________________________________
    _______________________________________________________________________________
    _______________________________________________________________________________
    _______________________________________________________________________________
    ____________________________________________________

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    根据对话内容，选择恰当的句子补全下列对话。（每小题1分，共 5分）
    (At the doctor’s)
    A: Good morning, doctor!
    B:    【小题1】     What’s wrong?
    A: I have a sore throat.   【小题2】     
    B: How long have you been like this?
    A:   【小题3】   
    B: Have you taken your temperature?
    A: Yes. My temperature is OK.
    B:   【小题4】  Say “Ah”… You have a cold.
    A: Is it serious?
    B: Nothing serious.     【小题5】    You’ll get better soon.
    A: Thank you, doctor!

    A．I’m feeling terrible.
    B．I’m sorry to hear that.
    C．Open your mouth.
    D．I have a fever.
    E. Take the medicine three times a day.
    F. Good morning, young man!
    G. Since yesterday morning.
     
     

     

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    实验室用铜制取硫酸铜，将适量硝酸分多次加入到铜粉与稀硫酸的混合物中，加热使之反应完全，通过蒸发、结晶得到硫酸铜晶体。
    （1）为了节约原料，硫酸和硝酸的物质的量之比最佳为：    ；为了吸收该反应中产生的尾气，请选择下列中合适的装置       。

    （2）为符合绿色化学的要求，某研究性学习小组进行如下设计：
    第一组：以空气为氧化剂法
    方案1：以空气为氧化剂。将铜粉在仪器B中反复灼烧，使铜与空气充分反应生成氧化铜，再将氧化铜与稀硫酸反应。
    方案2：将空气或氧气直接通入到铜粉与稀硫酸的混合物中，发现在常温下几乎不反应。向反应液中加少量FeSO4，即发生反应，生成硫酸铜。反应完全后，加物质甲调节pH ，铁元素全部沉淀（一般认为铁离子的浓度下降到10-5mol·L-1，就认为沉淀完全），然后过滤、浓缩、结晶。
    已知：Ksp[Cu((OH)2]≈10-22， Ksp[Fe((OH)2]≈10-16,  Ksp[Fe((OH)3]≈10-38
    请回答下列问题：
    如开始加入的铜粉为3.2 g，最后所得溶液为500 mL,溶液中含有铁元素0.005 mol。
    ①方案1中的B仪器名称是       。
    ②为了使铁元素全部沉淀，应调节pH至少为_________。
    ③方案2中甲物质可选用的是             。
    A．CaOB．NaOHC．CuCO3D．Cu2(OH)2CO3 E、Fe2(SO4)3
    ④反应中加入少量FeSO4可加速铜的氧化，用离子方程式解释其原因        。
    第二组：过氧化氢为氧化剂法
    将3.2g铜丝放到45 mL 1.5mol·L-1的稀硫酸中，控温在50℃。加入18mL 10%的H2O2，反应0.5h，升温到60℃，持续反应1 h后，过滤、蒸发浓缩、减压抽滤等，用少量95%的酒精淋洗后晾干，得CuSO4·5H2O 10.5g。
    请回答下列问题：
    ⑤反应时温度控制在50℃~60℃不宜过高的原因是         ，
    ⑥本实验CuSO4·5H2O的产率为         。

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    In the mid 1990s, people started doing business on the Internet. At that time, there were two kinds of companies. First, there were traditional companies which sold things in stores. Then, there were Internet companies which didn’t have stores, they sold things only over the Net.
    Traditional companies didn’t want to lose any business. Quickly, they created their own websites and began selling things over the Net. These are the so-called “brick and click” companies. Many stores are made of brick, and you click on your mouse to buy things with your computer. That’s where the name “brick and click” comes from.
    By the late 1990s, e-businesses like Amazon.com, Buy.com, and eToys.com were in trouble. Their profits(利润) were not very high, and there was a lot of competition. Many of these businesses lost a lot of money, and in 2000, many e-businesses were out of business.
    In the world of e-commerce(电子商务), companies are fighting for every dollar and every customer. Will brick and click companies win the war? Only time will tell.
    【小题1】Many traditional companies created their own websites in               .

    A．the early l990s B．the mid l990s
    C．the late l990sD．1990s
    【小题2】Why were Internet companies in a lot of trouble in the late 1990s?
    A．Competition was heavy.
    B．Their websites were bad.
    C．They didn’t know what to sell.
    D．Their profits were high.
    【小题3】Which would be a brick and click company?
    A．A clothing company with no website.
    B．A bookseller with five stores and an Internet site.
    C．A video seller with a big website but no stores.
    D．A restaurant.

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