2014课程学习资料4b
4b
Unit 4 American Dream Unit 4 美国梦Section B: Text B Ben Carson: Man Of Miracles课文提要本文讲述了出身卑微的本·卡森如何从一个街头打架少年成长为国际知名的脑外科医生的人生历程。
该篇给予读者的重要启示是：人生的道路多种多样，人要有雄心壮志，没有人生来就是失败者；发奋努力，就会成功。
Unit 4 American Dream Unit 4 美国梦Section B: Text B Ben Carson: Man Of Miracles重点词汇学习1. surroundings: n.周围的事物，环境[例句]1.Animals in zoos are not in their natural surroundings.（动物园中的动物没有自然环境。
）2.Good work cannot be done in unpleasant surroundings.（在不愉快的环境中是不能做好工作的。
）3. Children learn from their surroundings.（儿童向周围的事物学习。
）[辨析]surroundings, circumstances, environment, settingsurroundings 指“周围的事物，环境”。
circumstances 指某事或动作发生时的“情况”，常与under或in连用，表示“在…情况之下”，如：Under no circumstances will we give up.（在任何情况之下，我们都不会放弃。
）environment 表示围绕某一特定的人或物并对其产生某种影响的“环境氛围”。
如：A child’s character is greatly influenced by his home environment.（孩子的性格在很大程度受家庭环境的影响。
2014年4月全国网络统考资料《大学语文B》第4套模拟题及参考答案
大学语文B4一、判断题1、王勃与孟浩然齐名，并称"王孟"。
（）答案：错2、"我喜欢热闹，也喜欢安静。
"是递进复句。
（）答案：错3、夏衍写有剧本《法西斯细菌》和《风雪夜归人》。
（）答案：错4、《左传·郑伯克段于鄢》中的共叔段是个贪婪狂妄、愚昧无知的人物。
（）答案：对5、王安石是北宋最有成就的诗人之一。
（）答案：对6、小说《菉竹山房》主要通过细节描写渲染环境气氛。
（）答案：对7、《楚辞》鲜明的地方特色是最主要的特征。
（）答案：对8、春秋战国时期影响最大的是儒、墨、道、法四家。
（）答案：对9、《我的帝王生涯》是一部历史小说。
（）答案：错10、学术论文的选题只要确有价值，不必考虑其现实需要。
（）答案：错11、郁达夫的散文平淡冲和，幽默轻松。
（）答案：错12、从康熙末年到嘉庆末年，剧坛最重要的动向是以昆曲为代表的雅部声腔的衰落和以乱弹为代表的花部声腔的崛起。
（）答案：对13、《漳河水》的作者是李季。
（）答案：错14、《稼轩词》的作者是吴文英。
（）答案：错15、词是一种语言并不齐一的新格律诗。
（）答案：对16、细节描写是《始得西山宴游记》的突出特点之一。
（）17、《世说新语》是志人小说的代表作。
（）答案：对18、散文《黄鹂--病期琐事》主要表达了对养鸟人艰辛生活的同情。
（）答案：错19、"唐宋八大家"名称正式确立于茅坤的《唐宋八大家文钞》。
（）答案：对20、舒婷的《双桅船》曾获全国中青年诗人优秀诗歌奖。
（）答案：错二、选择题1、下列不属于20世纪90年代散文作家的是（）。
A：邓拓B：刘亮程C：陈丹青D：沈宏非答案： A2、剧作《霓虹灯下的哨兵》的作者是（）。
A：贺敬之B：宗福先C：沈西蒙D：丛深答案： C3、下列不属于"结构第一"这一理论命题范围的是（）。
A：立主脑B：减头绪C：密针线D：重案头答案： D4、诗集《会唱歌的鸢尾花》的作者是（）。
(完整版)香港朗文4B复习提要.doc
Chapter 1 Join our club参加我们的俱乐部及句型一、四会join (join us) club Drama Club Sports Club加入（加入我）俱部俱部体育俱部Gardening Club get fit keep fit find out园俱部得健康保持健康了解，出play music make music have fun come on演奏音制作音玩得开心来吧，加油act out a play dress up because improve (your English) 表演盛装 ,打扮因提高（你的英）pet interest grow take care of物趣种植照二、三会turn to healthy poster aplication forms向健康的海申表choose learn hand in suggest学上交建三、重点句型1. Which club do you want to join? 你想参加什么俱部？I want to join the ⋯ club.2. Why do you want to join ⋯club? 你什么想参加⋯⋯俱部？Because I like ⋯ ing. 因我喜⋯⋯Because I want to + 原形因我想⋯⋯3. It's time to + 原形干⋯⋯了。
4. I quite like English. 我相当喜英。
But I like drama best. 但是我最喜。
5. Let's join ⋯咱来加入⋯⋯复习提要I.四会单词Drama Club 俱部Sports Club 体育俱部English Club 英俱部Music Club 音俱部Art Club 俱部Gardening Club 园俱部have fun 玩得愉快keep fit 保持健康get fit 得健康improve 提高join 加入注意：1. get fit 是健康，是一个化的程，而 keep fit 是指在已健康的情况下，保持健康，两者有区。
牛津版4B全册教案
Unit 1第一课时一、教学内容Unit 1 A: Read and say.二、教学目标1、理解，掌握对话内容，用正确的语音语调朗读对话，初步表演对话。
2、正确运用日常交际用语Welcome to our school. Who’s that boy? I’m new here.3、能正确的听、说、读单词boy, woman, teacher, student, nurse三、教学重点能正确理解对话内容，朗读对话，初步表演对话四、教学难点流畅地朗读对话，并能在理解对话内容的基础上表演对话五、课前准备1、人物图片Mike ( student ), Miss Li( teacher ) Miss King ( nurse)Gao Shan (student )人物头饰Ben2、单词卡片student, teacher, woman, teacher ,boy六、教学过程（一） Free talk1、Hello, nice to meet you.2 、How are you ? / How are you this morning?3 、Are you happy today?4 、Welcome back to school.5、Good morning. Glad to meet you. Welcome back to school.（二） Presentation and practice: Ask and answer1、Good morning, boys and girls . Glad to meet you . Welcome back to school. 出示Welcome back to school. 理解并领读。
2、I have many pictures here .I like them very much. Do you like them?出示所有的图片3、根据出示的照片复习单词boy , girl，man, woman4、Do you know these boys and girls? (出示Mike , Gao Shan, NancyDavid, Helen 的照片）：(1) Who’s this boy? (Who’s that boy?)He’s _______. He’s a student. (学习新单词student )(2) Who’s this girl? (Who’s that girl?)She’s _________. She’s a student.5、Do you know these men and women?( 出示Miss Li, Miss GaoMiss King , Mr Green, Mrs Green 的照片）(1)Who’s this man? ( Who’s that man?)He’s _________. He’s a teacher.(学习新单词teacher)(2) Who’s this woman?(Who’s that woman)She’s __________. She’s a nurse. （学习新单词nurse?）（三） Play a game (通过游戏复习并学习新的日常交际用语)1、闭上眼睛猜一猜：(1) A: Who’s that ______?B: He’s(She’s) ________.A: He’s (She’s) a _________.B: You’re right. ( You’re wrong)(2) A: Excuse me. Are you _______?B:: No, I’m not.A: Are you _________?B: Yes , I am.2、让一学生戴上Ben 的头饰让另一学生猜T: Who’s this boy?S: He’s ________.T: No, you’re wrong.S: Are you ________?B: No, I’m not.S: Are you _________?B: No, I’m Ben.（四）Work in pairs1、Ben与老师对话:A: Hello, I’m Ben. I’m new here.B: Hello, I’m Miss Li. Nice to meet you.Welcome to our school.学习： I’m new here.Welcome to our school.2、学生与Ben 对话（五）朗读课文1、听录音，跟读。
2014全国卷IB4打印双面
2014年全国I卷英语AThe Cambridge Science Festival Curiosity Challenge Dare to Take the Curiosity Challenge!The Cambridge Science Festival (CSF) is pleased to inform you of the sixth annual Curiosity Challenge. The challenge invites, even dares school students between the ages of 5 and 14 to create artwork or a piece of writing that shows their curiosity how it inspires them to explore their world.Students are being dared to draw a picture, write an article, take a photo or write a poem that shows what they are curious about. To enter the challenge, all artwork or pieces of writing should be sent to the Cambridge Science Festival, MIT Museum, 265 Mass Avenue.Students who enter the Curiosity Challenge and are selected as winners will be honored at a special ceremony during the CSF on Sunday, April 21st. Guest speakers will also present prizes to the students. Winning entries will be published in a book. Student entries will be exhibited and prizes will be given. Families of those who take part will be included in celebration and brunch will be served.Between March 10th and March 15h, each winner will be given the specifics of the closing ceremony and the Curiosity Challenge celebration. The program guidelines and other related information are available at: http:// .21. Who can take part in the Curiosity Challenge?A. School students.B. Cambridge locals.C. CSF winners.D. MIT artists.22. When will the prize-giving ceremony be held?A. On February 8th.B. On March 10th.C. On March 15thD. On April 21st.23. What type of writing is this text?A. An exhibition guide.B. An art show review.C. An announcement.D. An official report.BPassenger pigeons (旅鸽) once flew over much of the United States in unbelievable numbers. Written accounts from the 18th and 19th centuries described flocks (群) so large that they darkened the sky for hours.It was calculated that when its population reached its highest point, they were more than 3 billion passenger pigeons—a number equal to 24 to 40 percent of the total bird population in the United States, making it perhaps the most abundant bird in the world. Even as late as 1870 when their numbers had already become smaller, a flock believed to be 1 mile wide and 320 miles (about 515 kilometers) long was seen near Cincinnati.Sadly the abundance of passenger pigeons may have been their undoing. Where the birds were most abundant, people believed there was an ever-lasting supply and killed them by the thousands, Commercial hunters attracted them to small clearings with grain, waited until pigeons had settled to feed, then threw large nets over them, taking hundreds at a time. The birds were shipped to large cities and sold in restaurants.By the closing decades of the 19th century, the hardwood forests where passenger pigeons nested had been damaged by American’s need for wood, which scattered (驱散) the flocks and forced the birds to go farther north, where cold temperatures and storms contributed to their decline. Soon the great flocks were gone, never to be seen again.In 1897, the state of Michigan passed a law prohibiting the killing of passenger pigeons but by then, no sizable flocks had been seen in the state for 10 years. The last confirmed pigeon in the United States was shot by a boy in Pike County, Ohio, in 1900. For a time, a few birds survived under human care. The last of them, known affectionately as Martha, died at the Cincinnati Zoological Garden on September 1, 1914.24. In the 18th and early 19th centuries, passenger pigeons____.A. were the biggest bird in the worldB. lived mainly in the south of AmericaC. did great harm to the natural environmentD. were the largest bird population in the US25. The underlined word ―undoing‖ probably refers to the pigeons’ ____.A. escapeB. ruinC. liberationD. evolution26. What was the main reason for people to kill passenger pigeons?A. To seek pleasure.B. To save other birds.C. To make money.D. To protect crops.27. What can we infer about the law passed in Michigan?A. It was ignored by the public.B. It was declared too late.C. It was unfair.D. It was strict.CA typical lion tamer（驯兽师）in people’s mind is an entertainer holding a whip(鞭) at a chair. The whip gets all of the attention, but it’s mostly for show. In reality, it’ the chair that does the important work. When a lion tamer holds a chair in front of the lion’s face, the lion tries to focus on all four legs of the chair at the same time. With its focus divided,the lion becomes confused and is unsure about what to do next. When faced with so many options, the lion chooses to freeze and wait instead of attacking the man holding the chair.How often do you find yourself in the same position as the lion? How often do you have something you want to achieve (e.g. lose weight, start a business, travel more)—only to end up confused by all of the options in front of you and never make progress?This upsets me to no end because while all the experts are busy debating about which option is been the people who want to improve their lives are left confused by all of the conflicting information. The end result is that we feel like we cant’ focus or that we’re focused on the wrong things, and so we take less action, make less progress, and stay the same when we could be improving.It doesn’t have to be that way. Anytime you find the world waving a chair in your face, remember this: All you need to do is focus on one thing,. You just need to get started. Starting before you feel ready is one of the habits of successful people. If you have somewhere you want to go, something you want to accomplish, someone you want to become…take immediate action. If you’re clear about where you want to go, the rest of the world will either help you get there or get out of the way.28. Why does the lion tamer use a chair?A. To trick the lion.B. To show off his skills.C. To get ready for a fight.D. To entertain the audience.29. In what sense are people similar to a lion facinga chair?A. They feel puzzled over choices.B. They hold on to the wrong things.C. They find it hard to make changes.D. They have to do something for show30. What is the author’s attitude towards the expert mentioned in Paragraph 3?A. Tolerant.B. Doubtful.C. Respectful.D. Supportive.31. When the world is ―waving a chair in your face‖, you’re advised to _____.A. wait for a better chanceB. break your old habitsC. make a quick decisionD. ask for clear guidanceDAs more and more people speak the global languages of English, Chinese, Spanish, and Arabic, other languages are rapidly disappearing. In fact, half of the 6,000-7,000 languages spoken around the world today will likely die out by the next century, according to the United Nations Educational, Scientific and Cultural Organization (UNESCO).In an effort to prevent language loss, scholars from a number of organizations--UNESCO and National Geographic among them—have for many years been documenting dying languages and the cultures they reflect.Mark Turin, a scientist at the Macmillan Centre Yale University, who specializes in the languages and oral traditions of the Himalayas, is following in that tradition. His recently published book, A Grammar of Thangmi with an Ethnolinguistic Introduction to the Speakers and Their Culture, grows out of his experience living, working, and raising a family in a village in Nepal.Documenting the Thangmi language and culture is just a starting point for Turin, who seeks to include other languages and oral traditions across the Himalayan reaches of India, Nepal, Bhutan, and China. But he is not content to simply record these voices before they disappear without record.At the University of Cambridge Turin discovered a wealth of important materials -- including photographs, films, tape recordings, and field notes --which had remained unstudied and were badly in need of care and protection.Now, through the two organizations that he has founded--the Digital Himalaya Project and the World Oral Literature Project--Turin has started a campaign to make such documents, for the world available not just to scholars but to the younger generations of communities from whom the materials were originally collected. Thanks to digital technology and the widely available Internet, Turin notes, the endangered languages can be saved and reconnected with speech communities.32. Many scholars are making efforts to ______.A. promote global languagesB. rescue disappearing languagesC. search for language communitiesD. set up language research organizations.33. What does ―that tradition’in Paragraph 3 refer to?A. Having full records of the languagesB. Writing books on language teaching.C. Telling stories about language usersD. Living with the native speaker.34. What is Turin’s book based on?A. The cultural studiesB. The documents available at Yale.C. His language research in Bhutan.D. His personal experience in Nepal.35. Which of the following best describe Turin’s work?A. Write, sell and donate.B. Record, repair and reward.C. Collect, protect and reconnect.D. Design, experiment and report.EThe jobs of the future have not yet been invented. 36 By helping them develop classic skills that will serve them well no matter what the future holds.1. CuriosityYour children need to be deeply curious. 37 Ask kids, ―What ingredients (配料)can we add to make these pancakes even better next time ?‖and then try them out. Ingredients make the pancakes better? What could we try next time?2. CreativityTrue creativity is the ability to take something existing and create something new 38 There are a dozen different things you can do with them. Experimenting with materials to create something new can go a long way in helping them develop their creativity.3. Personal skillsUnderstanding how others feel can be a challeng e for kids. We know what’s going on inside our own head, but what about others? Being able to read people helps kid from misreading a situation and jumping to false conclusions. 39 ―Why do you think she’s crying?‖ ―Can you tell how that man is feeling by looking at his face?‖ ―If someone were to do that to you, how would you feel?‖4. Self Expression40 there are many ways to express thoughts and ideas –music, acting, drawing, building, photography. You may find that your child is attracted by one more than another.A. Encourage kids to cook with you.B. And we can’t forget science education.C. We can give kids chances to think about materials in new ways.D. So how can we help our kids prepare for jobs that don’t yet exist?E. Gardening is another great activity for helping kids develop this skill.F. We can do this in real life or ask questions about characters in stories.G. Being able to communicate ideas in a meaningful way is a valuable skill.第一节完形填空As a general rule, all forms of activity lead to boredom when they are performed on a routine (常规) basis. As a matter of fact, we can see this 41 at work in people of all 42 . For example, on Christmas morning, children are excited about 43 with their new toys. But their 44 soon wears off and by January those 45 toys can be found put away in the basement. The world is full of 46 stamp albums and unfinished models, each standing as a monument to someone’s 47 interest. When parents bring home a pet, their child 48 bathes it and brushes its fur. Within a short time, however, the 49 of caring for the animal is handed over to the parents. Adolescents enter high school with great 50 but are soon looking forward to 51 . The same is true of the young adults going to college. And then, how many 52 , who now complain (抱怨) about the long drives to work, 53 drove for hours at a time when they first 54 their driver’s license (执照)? Before people retire, they usually 55 to do a lot of 56 things, which they never had 57 to do while working. But 58 after retirement, the golfing, the fishing, the reading and all of the other pastimes become as boring as the jobs they 59 . And, like the child in January, they go searching for new 60 .41. A. principle B. habit C. weaker D. power42. A. parties B. races C. countries D. ages43. A. working B. living C. playing D. going44. A. confidence B. interestC. anxietyD. sorrow45. A. same B. extra C. funny D. expensive46. A. well-organized B. colorfully-printedC. newly- collectedD. half-filled47. A. broad B. passing C. different D. main48. A. silently B. impatientlyC. gladlyD. worriedly49. A. promise B. burden C. right D. game50. A. courage B. calmnessC. confusionD. excitement51. A. graduation B. independenceC. responsibilityD. success52. A. children B. students C. adults D. retirees53. A. carefully B. eagerlyC. nervouslyD. bravely54. A. required B. obtainedC. noticedD. discovered55. A. need B. learn C. start D. plan56. A. great B. strong C. difficult D. correct57. A. time B. moneyC. skillsD. knowledge58. A. only B. well C. even D. soon.59. A. lost B. chose C. left D. quit60. A. pets B. toys C. friends D. c olleagues第二节语法填空Are you facing a situation that looks impossible to fix?In 1969, the pollution was terrible along the Cuyahoga River Cleveland, Ohio. It 61 (be) unimaginable that it could ever be cleaned up. The river was so polluted that it 62 (actual) caught fire and burned. Now, years later, this river is one of 63 most outstanding examples of environmental cleanup.But the river wasn’t changed in a few days 64 even a few months. It took years of work 65 (reduce) the industrial pollution and clean the water. Finally, that hard work paid off and now the water in the river is 66 (clean) than ever.Maybe you are facing an impossible situation. Maybe you leave a habit 67 is driving your family crazy. Possibly you drink too much or don’t know how to control your credit card use. When you face such an impossible situation, don’t you want a quick fix and something to change immediately?While there are 68 (amaze) stories of instant transformation, for most of us the 69 (change) are gradual and require a lot of effort and work, like cleaning up a polluted river. Just be 70 (patience)第一节短文改错Nearly five years before ,and with the help by our father, my sister and I planted some cherry tomatoes (圣女果) in our back garden, since then---for all these year---we had been allowing tomatoes to self seed where they please. As result, the plants are growing somewhere. The fruits are small in size, but juicy and taste. There are so much that we often share them with our neighbors. Although we allow tomato plants to grow in the same place year after year, but we have never had any disease or insect attack problem. We are growing wonderfully tomatoes at on cost!第二节书面表达假定你是李华，计划暑假间去英国学习英语，为期六周。
4b复习课件
It’s my cake.
Let’s eat it by the lake.
We are in cAlasrsenyoowu. biultl?N幻ick灯is片abse1n3t(缺席）
. Is he ill? Can you give him a telephone call?
A: Are those trousers the little rabbit’s ? B: I don’t think so.
A: Whose shirt is it ? B: It’s Daddy monkey’s. A: Which season do you like ? B: I like spring . It’s warm. I have picnics with my friends.
WWehaaret cinacnlayssonuoswe. eb?utWNihckatiscaabnseynto(缺u s席e）e? .In the tree, in the tree?
Is he ill? Can you give him a telephone call?
I can see a monkey. I can see a monkey, In the tree, in the tree.幻灯片 8
大声、流畅、有节奏读
大声、流畅、有节奏的表演读
We are in class now. but Nick is absent(缺席）
.
I1s.Sheuibllj?eCctasn 幻you灯gi片ve h1im6 a telephone call? 2.Whose cake is this?幻灯片 17 3.Are you ill?幻灯片 18 4.Doctor Wu幻灯片 19
全册要点整理电子版(英语朗文4B)
全册要点整理电子版(英语朗文4B)-CAL-FENGHAI-(2020YEAR-YICAI)_JINGBIANChapter 1 Join Our ClubKey words核心词汇（要求能够正确认读、拼写、互译）戏剧 d_________运动 s_________英语 E_________音乐 m_________美术 a_________园艺 g_________ 宠物 p_________ 数学 m_________社团 c_________ 最好的 b_______ 为什么w_______ 因为b__________Extension Words拓展词汇（要求能够正确认读、在语篇中理解意思）加入j_______ 海报p________ 表演a_______ 剧本p______十分喜欢 q________ l_________ 提高i____________ 学习l__________把宠物带学校来 b_________ my pet to school 真正好的图画a r________ g_______ p_______ 我喜欢运动胜过园艺。
（better than）______________________________________Key sentences & grammars主要句型和语法（要求能够正确认读、理解，并在相应语境中应用）1. 你为什么想要加入戏剧社团？____________________________________________________2. 因为我喜欢戏剧。
______________________________________________________________3. 我喜欢英语、绘画和戏剧。
不过我最喜欢的是戏剧。
_______________________________________________________________________________4. 我也最喜欢戏剧。
典范4b Lesson 14
小偷
Question
What
did Alex say?
词语解释
give
a grin
笑了笑
Questions
1.What did Chip asked?
2.What did Wilf say?
词语解释
dy 女士
2.again 又一次
Question
What
did Sally say?
2. Did the man stop? 3. Did the children raced as fast as they could?
词语解释
race
could
as fast as they
飞快的追上去
Questions！
1.What did Wilf yelled ?
2.What did Sally do? 3.Did the man stopped?
2.What did Sally took them see?
词语解释
gasped
倒吸了一口气
Questions！
1. Where did Sally go？
2.What did they think the man is doing?
词语解释
report
报告
stolen
偷
Questions！
Questions！
How many blue butterflies did Chip saw?
词语解释
have
seen
已经看见
Question
What
did Wilma ask for?
词语解释
2014年度会计人员继续教育培训课程考试试题及答案学习资料
2014年度会计人员继续教育培训课程考试试题及答案【1】【判断】【2分】新修订的《事业单位财务规则》共有十二章六十八条，增加了财务监督的内容。
【2】【判断】【2分】信息技术的采用必将彻底消除人为操纵因素，保护信息安全。
（）解析信息技术的采用应尽量消除人为操纵因素，保护信息安全。
【3】【判断】【2分】无形资产预期不能为行政单位带来服务潜力或经济利益的，也不应该按规定将该无形资产的账面价值予以核销。
（）【4】【判断】【2分】单位应当根据批复的预算安排各项收支，确保预算严格有效执行。
单位应当建立预算执行绩效考核机制。
（）解析根据《行政事业单位内部控制规范（试行）》要求：单位应当根据批复的预算安排各项收支，确保预算严格有效执行。
单位应当建立预算执行绩效考核机制。
【5】【判断】【2分】行政单位不需将各项支出全部纳入单位预算。
【6】【判断】【2分】单位应当加强内部控制关键岗位工作人员业务培训和职业道德教育，不断提升其业务水平和综合素质。
（）解析单位应当加强内部控制关键岗位工作人员业务培训和职业道德教育，不断提升其业务水平和综合素质。
【7】【判断】【2分】单位应当建立与建设项目相关的议事决策机制,严禁任何个人单独决策或者擅自改变集体决策意见。
（）解析《行政事业单位内部控制规范（试行）》要求单位应当建立与建设项目相关的议事决策机制,严禁任何个人单独决策或者擅自改变集体决策意见。
【8】【判断】【2分】行政单位取得资产时没有支付对价的，如果没有相关凭据也未经评估，其同类或类似资产的市场价格无法可靠取得，所取得的资产应当按照名义金额计量。
（）【9】【判断】【2分】行政单位的“其他应付款”主要核算行政单位因购买物资或服务、工程建设等应付的偿还期限在1年以内（含1年）的款项。
（）【判断】【2分】财政拨款结余是单位年度财政项目补助收支差额中，符合财政拨款结【10】余资金性质的数额。
（）【判断】【2分】事业单位开展非独立核算经营活动的，应当正确归集开展经营活动发【11】生的各项费用数；无法直接归集的，应当按照规定的标准或比例合理分摊。
4B_Project_1(1)_
go to bed
When do you go to bed?
:
：
8:40
…
read books
take a shower
：
go to school
8:40
read books /take a shower
What subjects do you have at school?
School subjects
Colourful school life
Design(设计): An ideal day (理想中的一天)
多彩，丰富有趣，而合理
Tips: 1. 从周一到周五选择一天进行设计。 2. 选择你喜欢的课程和活动。 3. 小组内只能用
英语讨论哦！
Nancy’s Monday
Colourful school life Show: Your ideal day
They have Chinese lessons, too.
After school, they go to different clubs（俱乐部）. Some of them have a swimming lesson.
The girls like to have a cooking lesson.
Sometimes, they have PE lessons in the playground.
Sometimes, they have PE lessons in the gym(体育馆).
They have different (不同的)kinds of English lessons every day, such as reading, spelling（拼）and writing.
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第三节化合物薄膜太阳能电池一、化合物半导体材料基础常用于太阳能电池的半导体材料有一些典型特点。
首先半导体材料的禁带不能太宽，用作薄膜材料的必须在太阳能光谱范围内有高的光吸收系数；其次材料电性能优秀，缺陷态较低，能保证一定的载流子寿命和扩散长度，载流子复合率尽可能低以保证较高的光电转换效率，当然材料便于工业化生产且性能稳定，对环境无污染等也很重要。
图4-16是截取的元素周期表中几种常用于太阳能电池的半导体材料，以四族为中心，集中在二~六族，以三、五族元素最多。
四族元素的价电子数刚好为4，可以自己配对形成稳定的共价键结构，这种由单一元素形成的是元素半导体。
其他族的元素则可以几种元素配合，形成总的价电子数为8的稳定共价键结构，这种结构的半导体被称为化合物半导体。
图4-17给出了各种半导体材料的禁带宽度（能隙）同理想和实际太阳能电池光电转换效率的关系。
从理论上讲，能隙在1.4eV~1.5eV的材料具有最高的理论转换效率，Si显然不能满足，而化合物半导体材料却是能隙可以在1.1eV 到1.7eV 之間变换的直接半导体材料，光吸收系数非常大，适合薄膜化，不仅是禁带宽度，还可以通过对化合物组分的精确控制来调整材料的基本参数，例如晶格常数、带隙宽度等，也可以改变材料折射率、载流子迁移率、跃迁类型等等。
化合物半导体是非常优秀的薄膜太阳能电池材料。
图4-16 光伏电池中常用的半导体元素图4-17 光伏材料禁带宽度同变换效率的关系总之，相当于Si系列的太阳能电池，化合物半导体薄膜电池有以下特点：▪禁带宽度在1～1.7eV, 与太阳光谱匹配较好。
▪直接带隙材料，对阳光的吸收系数大，只要几个微米厚就能吸收阳光的绝大部分，因此是制作薄膜太阳电池的优选活性材料。
▪对温度不敏感，可在较高温度下使用；▪电子迁移率高，扩散长度大；▪重量轻、可在柔性基片上制作；▪无光电效率衰退效应。
化合物半导体可以通过掺杂和成分调整，改变导电类型。
化合物半导体也分为n型和p型，掺杂原理同Si半导体是一样的，例如化合物GaAs中掺Te，六价的Te替代五价的As 可形成施主能级，成为n型GaAs杂质半导体。
化合物GaAs中掺Zn（Mg），二价的Zn替代三价的Ga可形成受主能级，成为p型GaAs杂质半导体。
最为特殊的是化合物半导体的自掺杂作用，调整多元化合物半导体的成分，可以形成p型或n型半导体，不用外部掺杂，例如CIGS。
根据材料种类，化合物半导体薄膜电池主要分为三类。
分别是：▪III-V族：以GaAs、InP太阳能电池为代表，抗辐射能力强，主要用于空间和聚光电池；▪II-VI族：目前转换效率最高的是n型硫化镉(CdS)和p型碲化镉(CdTe)组成的太阳能电池。
性能稳定，可印刷制造，量产产品转换效率可达13%左右，但镉（Cd）有毒；▪多元：铜铟硒(CuInSe2)太阳能电池，又叫CIS电池。
引入元素Ga后可自由调整禁带宽度。
铜铟镓硒(CIGS)该电池目前处在兆瓦级中试生产阶段；二、几种典型的化合物薄膜太阳能电池特性及制备技术下面介绍几种已经商品化的化合物薄膜太阳能电池。
（一）II-VI族太阳能电池：CdS/CdTe薄膜太阳能电池CdTe因为其独有的四个特性非常适用于光吸收层（活性层）材料。
▪禁带宽度为1.45eV，对太阳能光谱非常匹配▪CdTe是直接带隙半导体材料，，光吸收系数很高▪强烈地趋向于生长成为符合化学匹配且为P型的半导体薄膜，同自然N型的CdS形成p-n异质结）▪目前正发展廉价生产的简单沉积技术，可快速大面积成膜：从pn结到电极全部可以用丝网印刷和烧结制成，制造方法简单，制造成本控制的很低，转换效率可达13%左右除此之外，CdTe电子迁移率高，对多结晶膜中晶粒大小要求低，在使用过程中没有光致衰降，稳定性好，如果采用50～100nm的N-CdS作为窗口层（2.4eV），理论效率可到30％，目前实验室可达开路电压0.88V，效率~19%，商业化电池效率平均～11％，最高可到13%。
但最大的问题镉（Cd）引起的公害，虽然CdTe是稳定化合物，而且薄膜化后用量少（1MWCdTe 组件250kg），但仍然被很多国家限制。
掺入后导致CdTe成n-型的元素有：In、Cl，导致其成p-型的元素有：Li、Na、Cu、N、P、Se等。
CdTe薄膜电池的经典结构如图4-18所示。
图4-18 CdTe薄膜电池的经典结构和能带结构CdTe电池制备时，首先在作为透明衬底的玻璃上沉积透明导电层（一般是In2O3或SnO2或两者结合。
然后沉积n型CdS膜，再沉积p型CdTe薄膜（通常3-7微米足够光吸收了），并进行特殊处理来改善CdS和CdTe之间p-n结的性能，例如在含氯（CdCl2）的气氛中400~500℃下退火数分钟等，最后在CdTe上沉积不透明低阻电极，例如Ni-Al，ZnTe：Cu等。
可以看出，生产过程中有含Cd物质的泄露等问题还是影响了该类电池的普及生产。
电池工作时，光通过玻璃衬底进入电池，光子穿过TCO膜和CdS膜，CdS是宽禁带半导体材料，禁带宽度为非常高2.42eV，因此虽然有光损失，同Si薄膜电池不同，在CdS薄膜中并没有光生载流子过程，CdTe薄膜才是电池的光吸收层。
这种仅仅用于构成pn结而本身不具备光吸收或光生载流子产生功能的部分被称为窗口层，在薄膜太阳能电池中经常采用。
光吸收后在p-n结附近产生电子-空穴对，在内建电场作用下电子穿过CdS/CdTe界面漂移到n型CdS薄膜中，空穴仍留在CdTe并聚集，最后经由背电极离开电池。
上图4-18显示了CdTe电池的能级结构示意图，CdS和CdTe有非常好的能级匹配。
电子在CdTe中有数ns的寿命，但由于电子迁移率高，有利于电子进入到CdS膜层中。
同非晶硅薄膜太阳能电池不同，由于CdS窗口层不产生光生载流子，因此是n-CdS作为面光面。
可以看出，三个界面是影响载流子收集率的关键所在：CdS／TCO界面、CdTe／CdS界面以及CdTe/背接触界面，目前的研究结果表明后两者存在的问题较多。
CdTe／CdS界面可通过退火来改善，降低CdS和CdTe之间的晶格失配导致的缺陷态。
另一方面，能隙较高的低掺杂p型半导体同金属很难形成欧姆接触，由于金属的功函数和CdTe半导体费米能级的不匹配，界面处总有势垒（肖特基势垒）存在形成阻挡层接触，接触电阻较大。
改善的方法是形成一个高p掺杂的表面p+，利用隧道效应空穴穿过肖特基势垒，例如图4-18中在电极和CdTe之间插入的ZnTe层。
CdS/CdTe薄膜是少有的可低成本大面积制备的半导体薄膜，这也导致了尽管Cd有非常大的毒性，生产企业宁愿承担全部Cd回收的任务也进行规模化生产的原因。
CdTe太阳能电池常用制备方法主要有下列几种：▪气相传输沉积法(Vaper Transport Deposition；VTD)不需真空，利用传输气体导入受热蒸发的CdTe源，将CdTe颗粒带入下方的基板上进行沉积。
沉积速度相当快，每分钟可达20微米，利于高速生产，是目前主流技术，流程如下图4-19所示。
图4-19气相传输沉积法示意图▪近距离升华(Close-Spaced-Sublimation：CSS)可以同时进行自掺杂，容易制备性能均一的小厚度CdTe膜层。
但大规模效率不如VTD。
▪丝网印刷，然后烧结：最高13%，规模生产光电转换效率低CdS/CdTe组件的结构和制备同Si薄膜电池类似。
需要注意的是在刻痕分割单元电池（子电池）时，宽度越大串联电阻增加，填充因子下降，但过密的划痕导致其占有面积增大，影响光利用率。
单元电池的宽度同电池电流密度有关。
电流密度越大，电池宽度就可以越窄。
CdS/CdTe单元电池宽度约在9~10mm，而非晶硅薄膜电池宽度可到10~20mm，后面讲述的CIS电池电流密度高，电压低，宽度仅6mm即可。
Cd的全球储量：600万t；Te全球储量：5.3万t，1MW、厚度3微米、效率9.3%的CdTe光伏电池消耗Cd94Kg，由于高毒性，虽然目前应用不错，但是很容易被其他电池取代的。
下图4-20是美国firstsollar公司屋顶CdS/CdTe光伏电池组件阵列外观。
图4-20 美国firstsollar公司屋顶CdS/CdTe光伏电池组件阵列外观（二）III-V族薄膜太阳能电池的代表：GaAs系列太阳能电池因为非常优秀的高温性能和抗辐射能力，GaAs太阳能电池是作为可替代Si的空间太阳能电池登上应用舞台的。
随着宇宙空间技术的发展，AlGaAs/GaAs单结空间电池的效率（AM0,4m2）也达到了21.7%。
同时GaAs也是聚光太阳能电池的最好选择，AM0,100倍聚光AlGaAs/GaAs单结太阳能电池效率可达24.6%。
多结级联GaAs太阳能电池的效率可以更高，双结GaAs太阳能电池的极限效率为30%，三结GaAs太阳能电池的极限效率为38%，四结GaAs太阳能电池的极限效率为41%。
高效率的GaAs太阳能电池不论多结还是单结都选用了AlGaAs 作为窗口层，下图4-21是一个典型的单结AlGaAs/GaAs的结构示意图，在该电池中，pn结由p型和n型掺杂的GaAs 构成，AlGaAs是一个宽禁带材料，为p型半导体，基本不吸收光能产生光生载流子，而作为钝化窗口层。
图4-21 单结AlGaAs/GaAs的结构示意图对化合物薄膜太阳能电池来说，窗口层非常重要。
对窗口层的首要要求是禁带宽度要大，没有光生载流子过程，可以透过所需要的光。
窗口层的作用在于它具有表面钝化作用，一是避免真正的光吸收层同金属电极直接作用，降低表面复合。
窗口层大多同光吸收层的半导体材料出于同类，在晶格匹配上有优势，因此对半导体表面缺陷有缓解作用，二是可以减小电极同半导体材料之间的能级差，降低电极和光吸收半导体直接的接触电阻，提高短路电流和填充因子。
第三，窗口层还可以通过更重的掺杂，例如上图中的窗口层AlGaAs 比p-GaAs 层掺杂高，记为p+，起到表面钝化作用，将电子反射回体内，阻挡光吸收层产生的电子扩散到表面复合掉，同时促进空穴扩散到电极处流出。
也有时窗口层兼有形成pn结的任务，例如CdS/CdTe薄膜太阳能电池中的n型CdS窗口层。
另外，薄膜太阳能电池也可以形成重掺杂的背电场层，作用同晶体硅电池中一样，如上图4-21中的n+层。
作为空间用聚光太阳能电池，光的利用率更加重要，所以某些GaAs太阳能电池还具有聚光太阳能电池的特有结构：内部Bragg反射器。
Bragg反射器常用在半导体激光及其他半导体光学器件中，通过两种不同折射率材料的组成，在一个比较严格的光谱范围内，接近100%的光谱可以得到反射。
每种材料对于给定波长可以选择的厚度为四分之一波长厚度。
这种折射率交互的周期性重复结构可以反射未被吸收的光子以便于活性层再一次吸收，增大了光电流。