第一篇:儿童两分钟英语演讲
small kindness welfare of others.when we read the daily newspapers, we are frequently appraised of the big kindnesses performed by well-to-do philanthropists who donate large sums of money for the establishment of schools, libraries, free hospitals for the poor, orphanages, and the like.these, of course, are laudable acts of charity that deserve wide public acclaim.but in my estimation, those many minor acts of kindness performed daily ion assorted situations by public-minded citizens who receive no recognition or plaudits from the the billionaire philanthropist who has given away a million dollars for the establishment of a new old people’s home.all try remedy the situation by launching a personal campaign to perform a small kindness each day, no matter how inconsequential it may seem, so that our society will be a much better place to live in.平凡的善行
平凡的善行就是一些我们在日常生活当中所做的、简单的好事。不只对我们的亲友,结全然陌生的人也一样;不是为了报酬,完全是出自
一种为他人福祉的慷慨、无私的精神。
我们每天看报,常得知富有的慈善家所作“伟大的善行”。他们捐很多的钱盖学校、图书馆、免费为穷人看病的医院、孤儿院等等。当然这 值得民众赞美的慈善行为。但我认为,那些没受到大众传播媒介褒奖或赞扬、具有服务大众热忱的市民所作较小的善行,一样值得赞赏。我认为在上帝眼中,一个好心的白领阶级,即使在工作一天后极度疲惫,在挤满通勤者的火车上让位给老弱或残障者,也一样值得赞美,甚至比那些捐一百万元建造一座新的老人院的亿万慈善家更值得表
扬。
在任何国家的大城市,居民的共同倾向就是“自扫门前雪”。对于那些无法赶上这种快速竞争步调的人,气氛是冷默无情的。让我们发起个人运动,试着来修正这促情形。无论事情多么微不足道,每天是行一
善,那么我们的社会将会更适于居住。remuneration n.报酬 apprais v.报告,通知 philanthropist n.慈善家 orphanage n.孤儿院 laudable a.值得赞美的 acclaim n.称赞,喝采 plaudit n.赞扬 crippled a.残废的 atmosphere n.气氛
inconsequential a.不重要的篇二:两分钟的英语演讲稿
两分钟的英语演讲稿 中学生感恩英语演讲稿
the poet said: spring flowers to the door pushed open。i said: thanks giving to the door pushed open the living.if you carefully listen to the voices of flowers, are everywhere harmonious life movement.诗人说:花朵把春天的门推开了。我说:感恩把生活的门推开了。只要你用心去听花开的声音,生活到处都是和谐的乐章。
then, as a middle school student, how thanksgiving? 那么,作为一名中学生,怎样感恩呢?
first thanksgiving their parents, because everyones life is a continuation of the parents of one blood, all of the parents gave us love, let us enjoy the human world of affection and happiness, therefore, we would like to thank the parents.首先要感恩自己的父母,因为每个人的生命都是父母血脉的延续,父母给了我们全部的爱, 让我们享受到了人世间的亲情和幸福,因此,我们要感谢父母。
teachers are our growth领路人, are our friends, teachers care for us , their words and deeds, let us benefit for life, we pay for teachers efforts and sweat, we should thanksgiving teachers.老师是我们成长的领路人,是我们的朋友,老师爱护我们,言传身教,让我们受益终身,老师为我们付出心血和汗水,我们应该感恩老师。
同学是我们学习生活的同伴,同学间互相鼓励,互相帮助,共同战胜困难与挫折,共同品尝学习的成功与快乐,我们应该感谢天天与我们相伴的同学。
thanksgiving-fighting, thanksgiving unlimited!students, and society thanksgiving!let us always to the life caring and full of love and love!感恩无痕,感恩无限!同学们,学会感恩吧!让我们的生活永远走向关怀,充满真情和爱心!
高中英语演讲稿:怎样才能学好英语
as everyone knows,english is very important today.it has been used but for myself,i learn english not only because of its importance and its usefulness,but also because of my love for it.when i learn english, i can feel a different way of thinking which gives me more room to touch the world.when i read english novels,i can feel the pleasure from the book which is different from reading the translation.when i speak english, i can feel the confident from my words.when i write english,i can see the beauty which is not the same as our chinese...i love english,it gives me a colorful dream.i hope i can travel around the world one day.with my good english, i can make friends with many people from different contries.i can see many places of great intrests.i dream that i can go to london,because it is the birth place of english.i also want to use my good english to introduce our great places to the english spoken people,i hope that they can love our country like us.i know, rome was not built in a day.i believe that after continuous hard study, one day i can speak english very well.if you want to be loved, you should learn to love and be lovable.so i believe as i love english everyday , it will love me too.i am sure that i will realize my dream one day!thank you!中学生三分钟英语演讲稿
good morning,dear teacher and my friends.it’s a very intresting topic today.i think my dad was a hero for me when i was a young child.wed go fishing, walks, and other fun things for a kid.every child has a good and great father, and so do i.my dad played a very important role in my daily life`````exactly speaking, in my past 16 years.my father always stands in the center of my life,from past till now and possibly in the future.my family was rather poor when i was in my childhood.we didnt have our own house and had to live in a shabby,small room rented from my fathers factory.the room was so small that there was little space for people to walk.i didnt have my own bed and had to sleep with my parents.this is terrible both for my parents and me.but father made this all different!he works very hard on his own business, now we have our own 2 housese,surly,i have my own room.and he take our family so much happiness, richer and richer.when i was little, i did everything with my dad.you could always find me sitting on his knee or walking and doing everything with him.every night he would read me a bed time story and make the voices of each character.i learnt a lot from my daddy.i learnt to never take things to seriously and to always smile.years pasted, my father is over 45 now.it is time for me to look after him and i am sure i will do and we will live an even better life.and i will say,i really love you dad,cause you are the hero in my mind.thank you so much!say no to junk food good morning, everybody!boys and girls, please raise you hand if you don’t like fried chicken wings.(你可现场问问题)how about double cheese burger? raise you hands if you don’t like french fries.i can see so many people like fried chickens, double cheese burgers and french fries.now let me ask you one more question: raise you hands if you like junk food.i can see that nobody likes junk food.right? boys and girls, do you realize that the one you were in favor just now are junk foods.junk food is a slang word for foods with limited nutritional value.foods that are high in salt, sugar, fat or calories and low nutrient content.are junk foods.boys and girls, listen up!junk foods may cause hypertension junk foods may increase various kinds of cancer, cardiovascular disease, diabetes, and obesity boys and girls, i am not standing here to scare you eating healthy foods should start from the young so let us start from today let us say no to junk food boys and girls, it is not a matter how long you could live it is the quality of life that counts!god bless everybody!bye!ladies and gentlemen, good morning.it’s my great honor to be here and i am very happy to see you all.thank you for being here.what i am going to talk about today is how to speak good english.english may be the most important factor in deciding which countries are leaders in the future.the language of the most advanced management and technology is undoubtedly english.being able to absorb this information is really the key to the new century.in the 21century.we can’t go there and speak our own language because nobody is going to learn it in order to understand us.our asian rival, india, has surged ahead of other developing countries in information technology because of its superior english skills.unless we are able to master english, we will not be able to get our population to use it and take advantage of the new economy.there is an urgent need to have a workforce which is proficient in the language in view of the information technology onslaught.second, about learning english, i think laying a strong foundation is the first and most important step.in other words, you should read and speak english every day.memorizing new words and phrases is also helpful.of course, learning english takes some time, so don’t be impatient.remember, rome wasn’t built in a day.and then since english is not our native tongue, we must develop the muscles of your speech organs to produce unfamiliar sounds.when you read, read as loudly as possible, as clearly as possible and as quickly as possible.tongue muscles’ training is of importance in learning any foreign language.every time you move your mouth, your memory will deepen, your muscles will strengthen.you can make it.1-1 self-introduction 一口气英语演讲
ladies and gentlemen: im happy to be here.id like to introduce myself.my name is pat.everyone calls me pat.you can call me pat.im from taiwan.i was born in taiwan.i grew up in taiwan.right now, i’m a student.im eager to learn.i study very hard every day.i like being a student.i like going to school.i think its interesting and fun.im also learning english.i enjoy speaking english.its my favorite class.im a friendly person.i always try to be polite.i like to get along with everyone.i want to be your friend.i hope we can meet.what do you say? lets be friends.lets get together.please introduce yourself.介绍自己/女士们先生们:我很高兴来到这里,我想要介绍自己,我的名字是帕特,人人都叫我帕特,你们可以叫我派特.我来自台湾,我出生在台湾,我成长在台湾。现在,我是一名学生,我渴望学习,我每天都非常努力地学习。我喜欢当学生,我喜欢上学,我认为那是非常有趣的事,我也在学习英语,我喜欢说英语,这是我最喜爱的课。我是一个友善的人,我总是试着有礼貌,我愿意和大家好好相处,我想成为你的朋友,我希望我们能认识,你说怎么样?让我们作朋友吧,让我们聚在一起吧,请介绍一下你自己吧。1-2 my hobbies 我的业余爱好
我有很多业余爱好,我喜欢做很多事,让我来告诉你们一些.我喜欢电动玩具,电脑游戏也很棒,我可以整天玩这些东西,我喜欢搜集卡片,我用它们来玩游戏,我会和朋友交换卡片,我还喜欢运动,我喜欢户外活动,我喜欢新鲜的空气和阳光,骑脚踏车很有趣,溜直排轮(汗冰鞋)很棒,游泳是我最喜欢的运动。另外,我喜欢画画,我喜欢看漫画书,那请不要告诉我的父母,此外,我喜欢音乐,我喜欢唱歌,我正学习乐器。当然,我喜欢学习英语,我喜欢和外国人交谈,我爱看迪斯尼漫画,我喜欢做的事很多,我要说的也有很多,我会留到改天再说(且听下回分解)。1-3 my family i have a wonderful family.im lucky to be a part of it.let me tell you about them.my family name is lee.my family history is long and proud.there are five people in my family now.my parents love me very much.they do a lot for me.when i need help, they are always there my dad is a strong guy.hes honest and hardworking.hes like a superhero to me.my mom is a smart woman.she can do almost anything.i just cant praise her enough.i have two siblings.they are my older brother and younger sister.sometimes we argue, but we mainly get along.my family likes being together.we like eating out and going to the movies.we also enjoy hiking and having picnics.my family isnt perfect.we have our ups and downs.but we always forgive and make up.our motto is united together forever.ill always cherish my family.i hope your family is lovely, too.我有一个很棒的家庭,我很幸运是它的一分子。让我告诉关于这个家的事吧。我们家姓李,我的家族非常优秀,现在我们家有五口人,我的父母非常爱我,他们为我做了很多事,我什么时候需要帮助,他们总是给我帮助。我爸是个坚强的人,他是个诚实而勤劳的人,对我来说他就象超级英雄。我妈妈是个聪明的女人,她几乎会做任何事情,我再怎么称赞她也不为过,我有两个兄妹,他们是我的哥哥和妹妹,有时我们争吵,但大部分时间我们相处很好,我的家人喜欢吃饭和看电影,我们也喜欢去郊游和野餐,我们的家庭并不是完善无缺,我们的关系时好时坏,但我们总是很快就和好了,我们的座右铭是永远团结在一起,我要珍惜我的家庭,我希望你也喜欢你的家庭。1-4 my best friend 我最好的朋友
我有一个最要好的朋友。我们是在学校认识的。我们是同一年级的。他是个勤勉的、用功的学生。他非常勤勉。我从他身上学到很多。他帮我学数学。我帮助他学英文。我们是很棒的学习团队。他诚实又可靠。我完全信任他。我们总是把秘密告诉对方。他忠诚而勇敢。曾经有个恶霸欺负我。他马上就来救我。他体贴而且有礼貌。他会做小礼物送我。他总是记得我是生日。跟他在一起很有趣。他会讲好笑的笑话。他的故事使我哈哈大笑。他是个很棒的听众。他知道我什么时候抑郁。当我举丧时他会使我振作。他是独一无二的。.我们会永远做朋友。我希望你也向我一样有一个这样的朋 1-5 my daily schedule 我的日子是平凡的,我确信(bet)我过的日子就跟你们一样,让我告诉你们我每天都会做的事,我的闹钟6点半响,我从容(慢慢)地起床。我醒来以后会伸个懒腰,我会脱掉睡衣,我会很快地洗把脸,我会刷牙和梳头。我穿上制服,我把上学要用的东西装进书包,然后,我就穿上运动鞋就出门了。我从来不会不吃早餐,我会在家里吃或在上学的途中吃,但是我总是吃得很着急。放学后,我就去补习班(cram school),我在那里再用功念一次书,我会把当天的家庭作业做完。最后,我就回到家,放松休息一下,和我家人一起吃晚饭,我会看一下电视,我大约在9:30睡觉,我会很快睡着。
第二篇:英语演讲,两分钟
Good morning, my dear teacher and my dear classmates, I’m very glad to stand here to give you a speech.As we all know with a heart of thanksgiving is very important to society.Yes, you may not be noble, but you must have a heart of thanksgiving.It is like a spice, if you start off with it, it will make your heart full of fragrance all the time.If you are a flower, please owe the sunshine.If you are a fruit, please owe the autumn.If you are a bird, please owe the sky.If you are a fish, please owe the ocean.What soul you have, what world you will have;what soul you have, what kind of life you will have.If your heart is clouded, your fate will be dark and gloomy;if you have the sunshine within, your life will be bright and happy.Life just like a mirror, when you smile to it, it will give you a same smile in return.So please be in a mood of thanksgiving to face the concerns of others and sincerely return.My topic is “Can money buy happiness”.As we all know, money can buy all the goods in our life, no matter how huge it is.A spaceship, for example, if you really feel your bank
account can afford it.However, when it comes to love, satisfaction, happiness and many other human feelings, it is completely not like this.The result of many recent research can support my point.They said that, though people received far more money than ever, their standard for happiness also rised.That means, if you had one yuan, a car might be your dream, but if you had one million, you might consider owning a space trip.So when people always hope for those they can not afford, they will push themselves to an unhappy situation.Anyhow, money equal wealthy in life but not happiness in mind.Only by changing our attitude to money and enjoying every day, can we obtain a truely happy future!
Life is What We Make It
Are you dissatisfied with today's success? It is the harvest from yesterday's sowing.Do you dream of a golden morrow? You will reap what you are sowing today.We get out of life just what we put into it.Nature takes on our moods: she laughs with those who laugh and
weeps with those who weep.If we rejoice and are glad the very birds sing more sweetly, the woods and streams murmur our song.But if we are sad and sorrowful a sudden gloom falls upon Nature's face;the sun shines, but not in our hearts, the birds sing, but not to us.The future will be just what we make it.Our purpose will give it its character.One's resolution is one's prophecy.Leave all your discouraging pessimism behind.Do not prophesy evil, but good.Men of hope come to the front.
第三篇:两分钟的英语演讲A heart of thanksgiving
Good morning, my dear teacher and my dear classmates, I’m very glad to stand here to give you a speech.As we all know with a heart of thanksgiving is very important to society.Yes, you may not be noble, but you must have a heart of thanksgiving.It is like a spice, if you start off with it, it will make your heart full of fragrance all the time.If you are a flower, please owe the sunshine.If you are a fruit, please owe the autumn.If you are a bird, please owe the sky.If you are a fish, please owe the ocean.What soul you have, what world you will have;what soul you have, what kind of life you will have.If your heart is clouded, your fate will be dark and gloomy;if you have the sunshine within, your life will be bright and happy.Life just like a mirror, when you smile to it, it will give you a same smile in return.So please be in a mood of thanksgiving to face the concerns of others and sincerely return.
第四篇:20篇你需要的两分钟英语演讲
大学物理阅读材料
第六篇 热核反应
第六篇 热核反应
能源是社会发展和进步的基石。如今,地球能源正面临严重短缺。煤、石油、天然气等天然能源矿藏的存量有限,随着人类多年的开采已经所剩无几。且不说这些宝贵的化工原料仅作为燃料使用所造成的极大浪费,就是谈到燃烧矿石燃料对环境所造成的严重污染和温室气体效应等后果,也让人们对直接消费这些天然能源再三反思。长期以来,人类一直在苦苦找寻体量大、污染少的新能源,以维持人类社会的持续发展。自从原子弹被研制成功并显示其巨大的威力后,立即引起了科学界对开发这种新能源——核能的巨大兴趣。
§6.1核能的利用
20世纪后半叶,核能的开发利用在世界范围内出现热潮,各种类型的核电站(也称作核反应堆)得到了异常迅速的发展。随着改革开放和国民经济发展的需要,我国也先后建成了数个核电站。但目前全世界所有核电站的原理,都是利用铀等大原子量的重核裂变成较轻的核而释放能量,也就是原子弹的反应机理。此类核裂变电站具有极大的运行安全风险和原料开采、处理以及反应后废料储藏、处理过程的极大核污染风险。15年前的乌克兰切尔诺贝利核电站、稍后的美国三里岛以及日本等都发生过极其严重的核事故灾难,至今还常有这些事故后遗症影响的报道见诸报端。其所依赖的核裂变原料铀不仅开采处理的过程非常困难和危险,就其在地球上的储量来说,也极其有限,因此,它远非是人们所希望的新能源。
而另一种核能,核聚变能,它很不同于我们在现存的核电站所利用的核能形式。正如现有核电站的发电机理是原子弹爆炸一样,利用核聚变能所建成的核电站的核能机理是热核氢弹。它是在当两个轻核聚合成一个较重的核时释放出巨大的能量。尽管同是核反应,聚变和裂变却有着极大的不同。由于要使两个轻核发生聚合必须克服巨大的排斥静电势,由实验资料得出,为使两个氘核相遇,它们间的相对速度必须大于每秒700公里,在如此高速下的氘核早已成为温度在5千万℃以上的物质的第四态——等离子体了。这也是我们把聚变称为热核反应的原因。
太阳是一个由高温等离子体组成的巨大能量源泉,它的光和热都是来源于经
大学物理阅读材料
第六篇 热核反应
久不熄的热核聚变反应。如果实现人工控制下氢元素的核聚变反应即受控热核反应,那么在地球上同样可以创造出一个个具有不竭能量的人造太阳。利用氢的同位素氘和氚的原子核实现核聚变的热核反应堆,人类在地球上可以建造类似于太阳上的热核聚变而放出能量的新能源装置。这种装置所提供的能源,不仅极少污染,而且廉价,资源无限,因此它是永久性解决人类能源问题的唯一途径,单靠海水为原料进行核聚变反应,就能满足人类100亿年的用电需求。
研究核聚变有两种途径,一种是磁约束类型,一种是惯性约束类型,托卡马克属于前者。50多年来,全世界共建造了上百个托卡马克装置,其中包括中国建造的大小不等的十多个此类装置。随着装置技术性建设的发展和实验结果的推动,科学家和工程师们追求先进形式的托卡马克装置,以获得更加理想的结果,更加接近核聚变反应堆的目标。全超导托卡马克的建造就是在这样的理念下应运而生的。
§6.2托卡马克磁约束装置
聚变核反应是一种非常理想的潜在新能源,近年来,磁约束聚变在托卡马克类型的装置上取得了突破性的进展,从而开发聚变能的科学可行性终于在托卡马克上得到了证实。正因为此,一个国际热核聚变工程实验堆(ITER)正在进行工程设计,其聚变输出功率可达1500MW。
HT-7U超导托卡马克是国家“九五”大科学工程,它是一个具有非园截面的大型超导托卡马克装置。纵场电源是一个大容量高稳定度全控整电源,极向场电源满足建立等离子体和感应加热所要求的磁通变化及波形要求,并实现对等离子体电流、位移、形状和电流分布等的控制。
§6.2.1核聚变与等离子体
质量数很小的两个适当的原子核在一定条件下重新组合成一个质量数较大的原子核,会释放出能量,这就是人类利用核能的另一重要途径即核聚变的理论依据。
1929年,有人提出太阳中产生能量的过程就是质子的聚变反应。这些反应能在温度高达15×106K的太阳中心发生。
聚变反应所需的原料直接或间接地都是氘核(D)。单位质量的氘聚变所放出的能量是单位质量235U裂变所放出能量的4倍左右。这是聚变核反应作为一
大学物理阅读材料
第六篇 热核反应
种潜在的新能源的突出优点之一。核反应是在原子核的热运动中发生的,所以称为热核反应,如果这种反应能够加以控制,则称为受控热核反应。计算得知温度达到108K-109K就可以发生聚变反应。要实现作为潜在能源的核聚变反应,只能通过高温等离子体的方法。在高温等离子体中氘核和电子处在几乎相同的高温状态中。而且,在等离子体中,氘核与电子作无规热运动,互相不断地碰撞着。因此,可以说高温等离子体物理学是核聚变的理论基础。
作为一种能源的核聚变反应堆,不仅要求等离子体的温度必须高到使离子能够克服彼此之间的库伦斥力而相互碰撞发生聚变反应,并且要求从等离子体发生聚变反应中释放的能量必须大于用以产生和维持高温等离子体所需的能量。劳逊作了核聚变等离子体中的能量平衡计算,设等离子体的密度为n,加热到温度T,该高温等离子体维持时间为τ。对于氘氘(D-T)反应,当等离子体温度为10keV时,实现能量收支平衡的nτ值是1020m-3s,如果实验上达到了劳逊判据要求的参考值,那就证明了核聚变的科学可行性。当Ti=30 keV时,nτ大约为1.5×1020m-3s,达到了热核点火条件。
§6.2.2磁约束托卡马克装置
核聚变等离子体温度极高,带电粒子的动能10 keV相当于温度108K(1eV=11600K)。磁约束就是利用磁场来将高温等离子体约束在一定的区域内(见图1),使之达到劳逊条件所要求的参数范围。
磁场对等离子体的约束能力在于磁场与等离子体之间有相互作用力。这些作用力包括三个方面,即磁场对等离子体中每个带电粒子的“洛伦兹力”;以及由此对等离子体产生的宏观效果磁应力;当等离子体中有电流通过时,除外加磁场产生的作用力外,电流本身产生的磁场还会产生一种箍缩力。
大学物理阅读材料
第六篇 热核反应
§6.2.3 EAST全超导托卡马克完成首次工程调试
由我国自行设计、研制的世界上第一个全超导托卡马克 EAST(原名HT-7U)核聚变实验装置,于2月1日到3月17日成功进行了首次工程调试。本次工程调试的主要目的是检验主机的性能以及相关分系统的能力,探索未来可行的运行模式,测量主机和主要分系统的关键技术参数,验证各种安全保护系统的可靠性, 为年内成功运行提供必要的数据和积累经验。在调试中,最受关注的低温调试和磁体通电测试获得圆满成功。
在真空和低温条件就位后,从3月13日到3月得离子体所的相关人员对纵场磁体和12个极向场磁体分别进行了260 次通电测试。最长通电时间达到5000秒,最大电流达到8200安培,相对应的装置中心场强已达到2特斯拉。总控系统、真空系统、低温系统、数据采集系统、水冷系统、电源系统、装置技术诊断系统、失超保护、真空磁位形测量系统、超导传输线、高温超导电流引线、铜电流引线以及等离子体控制系统运行正常,保证了通电测试的安全和成功。
图3 EAST(原名HT-7U)全超导托卡马克实验装置
“EAST(原名HT-7U)全超导托卡马克实验装置”是国家“九五”大科学工程,其开工报告于2000年10月获国家发改委正式批准。EAST装置集全超导和非圆截面两大特点于一身,且具有主动冷却结构,它能产生稳态的、具有先进运行模式的等离子体,国际上尚无成功建造的先例。等离子体所的科技人员经过5年多的自力更生、自主创新和艰苦奋斗,在2005年底基本完成了主机总装以及各分系统的研制和安装工作。他们解决了包括大型超导磁体研制与测试等许多超导托卡马克建设过程中的重大科学和技术问题,获得了一系列具有自主知识产权的、可对国民经济产生重要作用的高新技术。EAST的建设使中国聚变研究向前迈出
大学物理阅读材料
第六篇 热核反应
了一大步,赢得了国内外同行的敬佩和高度关注。
§6.3核聚变反应的研究和政治
随着中国、日本、韩国、俄罗斯、美国和欧盟6大ITER成员国6月28日在莫斯科敲定法国的卡达拉舍(Cadalache)为反应堆建设地,这一为期30年、共计投资将超过100亿欧元的国际超大型科学合作项目很快就将正式启动。“ITER”——拉丁文“道路”之意——是否真能为人类另辟蹊径,整个世界都在期待。酷暑严冬、暴风山洪„„被现代人类“剥削”的地球也在以自己的方式报复着人类。然而与生态气候所遭受的破坏相比,能源衰竭受到了更为广泛和急迫的关切。
实际上,宇宙中最常见的就是氢元素的聚变反应,所有的恒星几乎都在燃烧着氢。利用氢原子最容易实现的聚变反应是其同位素氘(读音刀,deuteri-um)与氚(读音川,tritium)的聚变。氘和氚发生聚变后,2个原子核结合成1个氦原子核,并放出1个中子和17.6兆电子伏特能量。每1升海水中含30毫克氘,30毫克氘聚变产生的能量相当于300升汽油,就是说,“1升海水等于300升汽油”。地球上海水中有45万亿吨氘,足够人类使用60亿年。ITER走向人间政治角力让ITER一波三折
事实上早在二战时期人类就早已实现了氘-氚聚变―――氢弹。但它比原子弹更具毁灭性和不可控性。如何将氢弹爆炸过程用人为手段大大减缓,其反应能量被缓慢而稳定地输出?这成为科学家们半个多世纪来为之奋斗的目标。
上个世纪50年代初,美国和苏联率先开始秘密地独立研究可控核聚变,然而随着研究的深入,理论和技术上遭遇的一个个障碍让各国认识到,只有开展广泛的国际合作才是加速实现核聚变能利用的唯一可行之路。热核聚变技术也成为冷战时期各国仍旧保持互通有无的特例。
1985年,美国总统里根和苏联领导人戈尔巴乔夫在一次首脑会议上提议,要求“在核聚变能方面进行最广泛的、切实可行的国际合作”。美苏两国首脑随后又与核技术领域处于领先地位的法国的总统密特朗进行了几次高层会晤,支持在国际原子能机构(IAEA)主持下,进行国际热核实验反应堆,即ITER的概念设计和辅助研究开发方面的合作。
1987年,IAEA邀请欧共体(欧盟前身)、美国、苏联、加拿大和日本的代表在维也纳开会并达成协议,五方合作设计建造国际热核实验反应堆,并由此诞生
大学物理阅读材料
第六篇 热核反应
了第一个国际热核实验堆的概念设计计划,也被称为“人造太阳”计划。
随后,由于苏联解体和美国以需要重新审议核聚变计划为由退出计划,ITER受到了很大影响,日本和欧盟国家成为ITER的主体力量,并在2001年完成了ITER的工程设计修改方案。
2003年2月18日,美国宣布重新加入这一大型国际计划,中国也于同日加入该计划,19日,国际热核实验反应堆计划参与各方在俄罗斯圣彼得堡决定,将于2013年前在日本、西班牙、法国和加拿大四国中的一个国家中建成世界上第一座热核反应堆。
ITER的投资和建设规模之庞大,交叉学科种类之多,实验设备之复杂,都决定了它必须由多国合力完成。然而在大投入所蕴涵的不可估量的经济利益和政治角力之下,各国选址之争一度让ITER“搁浅”。
在欧盟的协调下,候选国之一西班牙主动放弃,变成以法国为代表的欧盟与日本之争。2003年,华盛顿的一次会议上形成“两军对垒”态势―――欧盟、中国和俄罗斯主张把反应堆建在核工业基础已经相当雄厚的法国南部城市卡达拉舍;而美国、韩国和日本则主张建在日本的六所村。因为没有选择加拿大作为反应堆候选国,2004年初,加国宣布由于缺乏资金退出该项目。至此,ITER的六方参与国确定为中国、美国、俄罗斯、欧盟、日本和韩国。
法日两国的选址拉锯战也从2003年进入白热化。得到中俄支持的欧盟表现出空前团结。今年年初,在法国促请下,欧盟还曾放出风声:如果僵局无法打破,欧盟和法国将联合有关合作者另起炉灶。
这显然不是最佳选择。所幸的是,随着主要支持者美国的态度基于政治需要而逐渐暧昧,日本也不得不放缓口气。美国一度支持日本,那既是对伊拉克战争中日本坚定挺美的回报,也是对反战法国的报复;而如今时过境迁,急欲从伊战泥潭中抽身的布什政府重新开始“鼓吹”跨大西洋联盟的重要性。此外,美国是否真心愿意日本这个有过历史恩怨的盟友在事关战略的能源问题上实现自给,还要打上一个大大的问号。
失去了最大的“靠山”,日本在得到欧盟方面承诺可以10%的投资获得20%承包合同以及更多就业岗位的交易条件下,还是半推半就地放弃了选址竞争。ITER开建前的最后一个障碍终于得以扫除。中国强势参建10%投入换100%产
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第六篇 热核反应
出
按照六方达成的方案,欧盟将负责ITER建造经费的40%,法国作为项目建设地负担10%;其余50%由其他五国均摊。在这个国际合作项目之下,每个成员都享有均等权利,也就是说,中国可以用10%的投入分享到ITER全部知识产权和科技及商业利益。
中国在热核聚变研究领域已经取得包括建成了全超导托卡马克装置的一系列重大成果,是ITER项目决定接纳中国的重要原因。根据计划,ITER将于2015年前全部建成。在法国卡达拉舍这个集聚全世界热核聚变领域多达数万名顶级科学家的总部,10%的科研人员都将是中国人。他们将参与这一前沿课题,同时吸收先进技术,促进我国基础科学和应用技术的快速发展。如果项目发展顺利,届时ITER还将在各参与国建立分支机构,造出更多的“太阳”。
作为世界上最大的发展中国家,中国对可替代能源有着巨大的需求。参与ITER的中方首席科学家日前在接受新华社记者采访时也毫不讳言,“中国参与这一计划的最终目的是在中国独立建造反应堆。” ITER六大关键词