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青少年科技小论文题目怎么写高中英语

发布时间:2024-07-07 08:11:23

青少年科技小论文题目怎么写高中英语

In the modern world, many students are under too much But how can we solve this problems?The first,I think the most important thing is that we should learn to relax For example,we can listen to some interesting music,or we can read some The second,we can also pay a visit to somewhere beautiful to relax The third,we can talk our problems over with our teachers or our I do believe we can relieve our pressure by these

时下,许多人家用节能灯管换下日光灯管和白炽灯,但有一点要注意,在换灯管的操作中千万小心,别打破了灯管。无论灯管是新还是旧,打破都有毒。 日光灯、节能灯,都叫荧光灯。灯管内壁涂有荧光材料,管内装有汞蒸气和氩气。在一只40瓦的直管日光灯内含有约45~48毫克左右的汞。正常使用的荧光灯都是安全的,不会 对人体造成危害。若不慎打破了荧光灯管,灯管里的汞蒸气和有毒的荧光物质会迅速散布到室内空气中,会造成急性汞中毒。汞中毒,最初表现为一般性神经衰弱症状,如轻度头昏、头痛、健忘、乏力、多梦等,汞进入人体还会积累到肾、胸等组织和器官中,引起慢性汞中毒,出现精神症状,如性情抑郁孤僻而又急躁,易紧张激动与发怒而自己不能控制。手指、舌头、眼睛明显震颤,以手指及手部震颤最为突出。病情严重及病程长者牙齿松动并易脱落。 这算吗???

写科学小论文就是把自己在学科学、用科学的过程中看到、听到、想到的,经过整理、思考后将新的见解告诉大家。一篇科学小论文(以下简称小论文)应当包括论点、论据和论证三大要素。论点是小论文的灵魂,一般都以中心问题的形式出现,小作者围绕中心问题发表自己深刻而独特的见解。论据是为论点服务的,是为了使论点表述得更清楚明白而准备的事实材料。论证就是用论据证明论点的过程。科技小论文实际上是我们在课内外学科学活动中进行科学观察、实验或考察后一种成果的书面总结。它的表现形式是多种多样的:可以是对某一事物进行细致观察和深入思考后得出结论;可以是动手实验后分析得出的结论;也可以是对某地进行考察后的总结;还可以靠逻辑推理得出结论。那么,一篇高质量的科技小论文,要注意以下几点:一、选好课题撰写科技小论文,首先要考虑写什么,也就是课题的选择。选择课题是写好论文的关键。要注意以下原则:价值原则,即选题的理论价值和实用价值。要对其他的同学有启发、指导和参考的意义;可行原则,指主观和客观条件的可能性,即撰稿者个人的专业知识、理论修养、知识面、手头资料、实验条件、周围环境,不可贪大求深,应该量力而行;新颖原则,指课题应是他人未曾研究或研究过但未解决或完全解决,要注意“文贵创

科技小论文科技小论文,不混在一起的神奇水,这是在家就可以简单操作的科幻小发明。神奇水神奇的地方就在这里,有一杯颜料水和一杯普通的水,在颜料水的杯子上盖上一张明信片,倒过来,叠在另一个杯子上,再抽掉明信片,神奇的事发生了!在这时,大家都会想到,上面的水和下面的水一定会混在一起。可是,并没有!需要准备的东西有:两只杯子、明信片、一双筷子、颜料和食盐。在两个杯子里装水,其中一杯加一点颜料。往清水的那一杯里加入食盐,使它变为高浓度的食盐水。把明信片盖在装颜料水的杯子上,倒过来,同时用手紧紧摁住,不要让杯子里的水留出来。把盖上明信片的杯子叠在有盐水的杯子上。轻轻抽出中间的明信片。颜料水和食盐水不会混在一起。是很神奇吧!为什麽不会混在一起呢?高浓度的食盐水因为比颜料水重,所以颜料水不能混在食盐水中。虽然看不到食盐水里的盐,但是盐并没有消失。水的重量+物质溶液后的重量=水溶液的质量,也就是水100克+食盐10克=110克。所谓水溶液就是指盐等物质溶解在水中形成的溶液。水溶液的重量相当于物质溶解在水中后的总质量。是很神奇吧!五年级四班

青少年科技小论文题目推荐高中英语

据有幸飞上太空的宇航员介绍,他们在天际遨游地球映入眼帘的是一个晶莹的球体,上面蓝色和白色纹痕相互交错,周围裹着一层水蓝色的“纱衣”。可谁知道,这颗“宝石”正面临着资源危机,石油资源所剩无几,水资源被污染,大气层稀薄,有的地方甚至出现臭氧层的空洞,被太阳的紫外线无情的毁坏,森林资源大幅度减少,但还是被人们滥砍乱伐,或许你们没听见,地球母亲在呻吟啊!罪魁祸首不是别人,而是人类,是人类毫无节制地开采和破坏地球资源。拿石油来讲,它仅仅只够我们用五十年!于是人们开始“保护”地球资源,往汽油里添加乙醇(酒精)已是杯水车薪,而且要用大量的与人类息息相关食物——玉米等农作物来制作乙醇,乙醇本身就会破坏自然......在此,我向大家推荐一种新能源——太阳能,太阳能是取之不尽、用之不竭绿色环保能源。人们的科技水平已经能把太阳能转换成电能、热能等各种形式的能量,并且已开始应用。例如,我们用的太阳能热水器就是其中只一。太阳能热水器不但不利用和破坏地球资源,而且省时、省力、省钱。赤日炎炎的一天,当你出去工作,累的满头大汗,很想洗澡,这时却放出冰凉刺骨的自来水,使你打个哆嗦——感冒了。但是,如果有太阳能热水器,一回家就能冲个舒服的温水澡,冲掉你一身的疲惫;寒风呼啸的冬天,泡热水澡是最享受的一件事,此时,你只需打开太阳能热水器,热水哗啦啦的流出来,躺在浴池里尽情地享受只属于你的温暖吧!现在还发明了太阳能汽车。这种汽车不用烧汽油,而是靠车顶上的太阳能电池板吸收太阳光,并把太阳光转换为电能,储存下来,再由电能来带动汽车,没有发动机的噪音和尾气绝对环保。假如你坐在它的里面,只要打开卫星定位导航系统,输入你要去的目的地后,你只管听听音乐、欣赏路边风景,它会以最安全、最快捷的路线把你送到。太阳能是环保的绿色能源是我见过的最好的能源了。我们一定要好好地开发和利用上帝赐予我们宝贵的太阳能,让它为人类作出更多的贡献!

As human enters a age of information The advantages and disadvantages becomes increasingly The advantages are that internet made life much more convenient and People can shop, read, learn, interact and a whole lot more from their computer It draws the world closer and makes lifes There are also On the internet, everyone is invisisble, this makes online fraud and identitity theft increasingly popular and Also, on the internet, almost everyone can post or edit information, which means information on the web are not always Therefore, as we become more and more relient on the internt, it' ;s advantages and disadvantages should not be

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青少年科技小论文题目大全高中英语

(一)征文主题:“创模”·责任·行动据我收集到的一份报告说:“环境问题是由于人类不合理地开发和利用自然源所造成的。触目惊心的环境问题主要有大气污染、水质污染、噪声污染、食品污染、不适当开发利用自然资源这五大类。”一个个铁一样的事实告诉我们,它们像恶魔般无情地吞噬着人类的生命。它威胁着生态平衡,危害着人体健康,制约着经济和社会的可持续发展,它让人类陷入了困境。为此我作出宣告:“只要我们——人类有时刻不忘保护环境的意识,有依法治理环境的意识,地球村将成为美好的乐园”。未来的天空一定是碧蓝的,水是清澈的,绿树成荫鲜花遍地,人类可以尽情享受大自然赋予我们的幸福。 古往今来,地球妈妈用甘甜的乳汁哺育了无数代子孙。原来的她被小辈们装饰得楚楚动人。可是,现在人类为了自身的利益,将她折磨得天昏地暗。人类只有一个地球;而地球正面临着严峻的环境危机。“救救地球”已成为世界各国人民最强烈的呼声。 我为周围环境的恶化而感到心痛,我想:作为未来接班人的青少年,如果不了解人类环境的构成和环境问题的严重性,无视有关环境保护的法律法规,不去增强环境保护意识,自觉履行保护环境的义务的话,我们的生命将毁在自己的手中,老天将对我们作出严厉的惩罚。为此我下定决心要从我做起爱护环境,保护我们这个赖以生存的家园,做一个保护环境的卫士。 在刚过去的一年中,我积极参加学校开展的植树活动,带领我们初二(二)班干部创立了“绿色天使”植绿护绿小组,鼓励队员们在校园里认养了一棵小树苗,利用课余时间给它梳妆打扮,为它长成参天大树打下了基础。在学校组织的“让地球充满生机”的签字活动中,我郑重地在上面签下自己的名字,并写下了自己对环保的决心和期望,对美好未来的憧憬。我积极参加学校在世界环境日举行的有奖征稿,认真查阅、收集各类资料,进行社会调查,撰写有关环境治理设想方面的文章,我经常去参加学校组织的环保讲座,观看环保方面的录相带,积极参预环保知识问答调查活动,认真填写每一项提问。我参与了“红领巾植绿护绿队”的网站建设,在上面发布大量的环保图片和环保知识,以及关于环保的各方面的法律知识,我国在环保方面发展动向、世界各国的环境保护情况;每个月我都利用网络、报纸,查找一些最新的不同的专题和板块“环保资讯”来告诉大家;还定期制作一些宣传板来宣传环保知识和生活中的环保常识。提高了大家的环保意识;号召同学们从不同的方面来关爱自己的家园,从身边的小事做起,为周围的环境奉献自己的一份力量!我积极动员身边的人一起来依法保护和建设人类共有的同样也是仅有的家园,为促进经济和社会的可持续发展,为人类的文明做出贡献。我还和同学们共同发起“养一盆花,认养一棵树、爱惜每一片绿地,让我们周围充满绿色”和“小用塑料袋不使用泡沫饭盒和一次性筷子,让我们远离白色污染”的倡议。让我们放下方便袋,拿起菜篮子,让我们共同走向美好的绿色的明天,走向辉煌、灿烂的未来! “真正检验我们对环境的贡献不是言辞,而是行动。”虽然我现在做得只不过是一些微小的事,但是我坚信要是我们人人都有保护环境的责任心,从自己做起,从小事做起,携手保护我们的家园,自然会给人类应有的回报。在温暖的摇篮——草原上小憩;在慈祥的笑脸——天空下成长,在爱的源泉——河流中沐浴

As human enters a age of information The advantages and disadvantages becomes increasingly The advantages are that internet made life much more convenient and People can shop, read, learn, interact and a whole lot more from their computer It draws the world closer and makes lifes There are also On the internet, everyone is invisisble, this makes online fraud and identitity theft increasingly popular and Also, on the internet, almost everyone can post or edit information, which means information on the web are not always Therefore, as we become more and more relient on the internt, it' ;s advantages and disadvantages should not be

青少年科技小论文初中英语怎么写

LPSometimesthisfeelingseemstobeoneofindifference,butitisaconventionofcitylifetocurbone‘VO城市生活和乡村和农场生活大不相同。大城市的人更注意尊重个人隐私。有时候这种感觉似乎是一种冷漠,但是它是城市生活的一个约俗,以遏制一个人对陌生人的个人事务的好奇。村民和农民有可能所有的邻居对表现出极大的兴趣。城市给聪明的年轻人提供了机会,来自村庄和农场的求职者有往大都市发展的稳定趋势

第一篇Hi,I’m I'm 13 years old and I study in xxx Middle S My school is Every morning I get up at seven and have And then I go to school at half past Lessons begin at eight o’ We have four lessons in the morning and Chinese is my favourite We usually have 10 minute's break between two lessons and at about 12 o'clock we finish our morning I have lunch at school at twelve I like school lunch and I always have rice with meat and After lunch I often talk with my friends or play basketball with In the afternoon lessons start at half past one and finish at four o’ I play games after school with my friends and then go home at half past In the evening I do my homework and then watch TV At ten o’clock I go to It’s really a busy day but I like 第二篇 As we can see, the world population is growing rapidly day by So enough fresh water is needed to feed such a big What's more, with the development of industry, factories and vehicles produce poisonous gases or wastes, which consequently results in the pollution of Though fresh, a good amount of it can no longer be Only quite limited fresh water resource is available to human So it's high time for us human beings to take quick action to protect water Stop pollution and save water, otherwise, we cannot survive on the With fresh water, the world will be prosperous第三篇 保护水资源: As we can see, the world population is growing rapidly day by So enough fresh water is needed to feed such a big What's more, with the development of industry, factories and vehicles produce poisonous gases or wastes, which consequently results in the pollution of Though fresh, a good amount of it can no longer be Only quite limited fresh water resource is available to human So it's high time for us human beings to take quick action to protect water Stop pollution and save water, otherwise, we cannot survive on the With fresh water, the world will be 翻译如下:正如大家看到世界人口增长迅速日。 给这类大的人口需要有足够的淡水。 怎么还有与工业事务局研究工厂和车辆产生有毒气体或,因此导致污染的水的废物。 虽然新鲜的可以不再使用好的量。 只有很有限的新鲜水资源可供人类。 因此,它是我们人类采取快速行动,保护水资源的时候了。 停止污染和保存水,否则,我们不能生存在地球上。 新鲜的水世界将会繁荣。改革开放:It has been thirty years since China started reform and began a policy of opening up China to the outside This has resulted in great changes taking place in various With the nine-year compulsory education(九年制义务教育) program,all children have the chance to be In the past 30 years,China has made great progress in science and In 2003,China launched its first manned spaceship and fulfilled its first space walk in As economy is developing fast,people's living conditions have greatly In addition,there have also been great changes in The 29th Olympics were successfully hosted in Beijing and Chinese athletes won the most gold I'm really proud of the great achievements in the past 30 It is the leadership of the Communist Party and the great efforts of us Chinese people that made all these Nowadays,people are working hard towards a more advanced and harmonious I'm sure China will have a brighter future and Chinese people will live a happier 第四篇保护水资源: As we can see, the world population is growing rapidly day by So enough fresh water is needed to feed such a big What's more, with the development of industry, factories and vehicles produce poisonous gases or wastes, which consequently results in the pollution of Though fresh, a good amount of it can no longer be Only quite limited fresh water resource is available to human So it's high time for us human beings to take quick action to protect water Stop pollution and save water, otherwise, we cannot survive on the With fresh water, the world will be 翻译如下:正如大家看到世界人口增长迅速日。 给这类大的人口需要有足够的淡水。 怎么还有与工业事务局研究工厂和车辆产生有毒气体或,因此导致污染的水的废物。 虽然新鲜的可以不再使用好的量。 只有很有限的新鲜水资源可供人类。 因此,它是我们人类采取快速行动,保护水资源的时候了。 停止污染和保存水,否则,我们不能生存在地球上。 新鲜的水世界将会繁荣。改革开放:It has been thirty years since China started reform and began a policy of opening up China to the outside This has resulted in great changes taking place in various With the nine-year compulsory education(九年制义务教育) program,all children have the chance to be In the past 30 years,China has made great progress in science and In 2003,China launched its first manned spaceship and fulfilled its first space walk in As economy is developing fast,people's living conditions have greatly In addition,there have also been great changes in The 29th Olympics were successfully hosted in Beijing and Chinese athletes won the most gold I'm really proud of the great achievements in the past 30 It is the leadership of the Communist Party and the great efforts of us Chinese people that made all these Nowadays,people are working hard towards a more advanced and harmonious I'm sure China will have a brighter future and Chinese people will live a happier 翻译如下:这是三十年以来中国开始改革与开始的外部 This 中国开放政策,导致在各个领域发生的巨大变化。 于九年强制 education(九年制义务教育) 程序所有孩子都有机会被 In 在 30 年中国已取得很大进展科技 In 2003、 中国推出其第一次的载人的飞船和完成首次空间行走在 As 经济发展迅速、 人民生活条件大大改善。 此外,也有很大的变化在 The 29 奥运成功承载在北京和中国运动员赢得最大的金牌。 我的确感到自豪的丰功伟绩在过去的 30 It 是共产党的领导和我们中国人作出所有这些 Nowadays,people 正在努力向更先进,和谐 I 确信中国将会有一个光明的前景和中国人民将过幸福生活的努力。电脑利弊:The main disadvantages are: some of the young people are too obsessed with the network control poor, it will trap into the Relevant data show that young people indulge in network performance is more than 89 percent Online games will have a strong young vanity has led to some young people have an unhealthy psychological, severely hampered the normal development of young There are fighting games so that some young people think that real life can be like a virtual network of the world as ruled by the law of the jungle to the world today, leading toward the path of Play the role of those villains, so that boys like girls change, but it's like boys The trap of the second network, some people because of social discontent, the network's own desire to radiation, leading to others on the network by fraud, deceived many examples, list goes Many benefits, save time and effort before the provincial lesson entirely on hand-written, time-consuming and laborious, much more will have to Preparation of a computer is now "semi-automatic", and the school to teach all the prior knowledge input into the computer, after layout, modify, save, and finally print it out; the same can also copy the Computer is time-saving, labor-saving good helper, it gives me more time to study materials, the design of better teaching 第五篇I like badminton and basketball,basketball is my favourite sport,I like basketball I always wear a T-shirt,shorts and runners to play I can throw the basketball in the net, I think it is easy, but someone think it is hard, I can catch the basketball, On Sundays,I am a bbasketball I like to watch basketball game on TV, Yao Ming is my favourite basketball player, I want to be a real basketball player 第六篇Hello everyone !DO you like sports? Let me tell you whate my favorite sport Well I like tennis Becase of playing tennis makes me be healthy and You can run on the playgrond and enjoy it every So I really like playing tennis very mnch! 第七篇a meaningfull activity Last month I went to the hometown with my family,We decided to swim in the river where my father often swim when he was But when we got there,there was only a dirty river,so we thought we got to a wrong But there was a old man,he said:"Here is a place where you want to go"He look so sad when he said Then he said:"Two years ago,here was really a beutifu place,but one day,many visitors come here and threw rubbish The river be dirty and dirty,and it look like this now"When I heard this,I think we should protect our It was really a meaningful activity第八篇Our school has now started an activity called “Build Civilized Classes and a Harmonious C” The topic is “ Get Rid of Bad Habits and Greet Civilization” Bad habits do Some students throw rubbish everywhere or spit in Some wear long Others are even addicted to smoking and We require that the students break away from these bad We urge the students to wear their school uniform and be polite to During the activity, we’ll hold a picture show, a competition of classroom and dormitory decorations and so We all hope that we’ll build each class into a civilized one and our campus into a harmonious 第九篇My Birthday PartyIt’s J Today I am16 years I am going to have a party at home and I am waiting for all my friends to They are going to bring?lots of beautiful presents with My parents are preparing a lot of nice things to eat and At the party we are going to play games, sing songs, dance and listen to I think we will have a good

When my father was young, he practiced Chinese calligraphy every day and enjoyed Peking Opera with my grandfather on Now as his daughter, I type in English when communicating with my friends and enjoy surfing on the Internet during When I enjoy the pleasure and convenience that new technologies have brought me, some people cry out that as technology develops traditional cultures must be Is it true that we cannot have both? Different as my lifestyle is from that of my father, I still believe that the development of technology won't lead to the loss of On the contrary, it will facilitate the development of traditional Some people draw the conclusion that technology leads to the loss of tradition because they find nowadays many people,especially the young, take interest in new things like the Internet, thus make less contact with traditional However,decreased popularity isn't equal to With the development of technology, we have more choices of arts and In other words, many new forms of culture are coming into existence, which provide people with more choices rather than threaten the existence of the traditional In actuality, if we look at the tradition itself, we can find that great achievements have been made in many fields with the development of New operas are on show; new researches about history are going on; new facts about historical cities have been found; all of which can prove that technology can stay peacefully with In fact, technology works far beyond The development of technology boosts that of the On one hand,new technologies make the research for traditional cultures possible as well as provide advanced techniques of reserving historic Take calligraphy as an example, new ways of illumination, which is the fruit of Hi-tech, can prevent the color of scripts from On the other hand, the rapidly developing media such as the Internet and communication satellite provide traditional cultures with a stage to face the whole As we can see, after the short piece of ad of Shanghai E , more people will know the beautiful melody of "J"In addition, if we look back to history, we can find out that it was always in the era when economy developed greatly that cultures prospered the No doubt that the development of technology can guarantee that of economy, which eventually influences the prosperity of As we all see, the development of technology brings us richness, making the research and development of cultures affordable brings us more leisure time, making our desire to enjoy ntertainments After all, as the great philosopher Marx aid, "economy determine

青少年科技小论文题目怎么写高中

我先告诉你什么是科技小论文。 一些同学把写科技小论文看得很平常,认为是科学工作者的事,对我们少年儿童是高不可攀的。这完全是一种误解,同学们不仅能写而且可以写出质量较高的论文来。 科学工作者写的科学论文,是指作者根据所制定的科研项目和确定的科研课题,通过实验、观察等手段,获得大量的科学数据,在此基础上,再进行分析研究,得出科学结论,从而写出的科研报告。同学们写的科技小论文,比科学工作者写的科学论文内容要短一些,不要过于高深。 科技小论文实际上是同学们在课内外学科学活动中进行科学观察、实验或考察后一种成果的书面总结。它的表现形式是多种多样的:可以是对某一事物进行细致观察和深入思考后得出结论;可以是动手实验后分析得出的结论;也可以是对某地进行考察后的总结;还可以靠逻辑推理得出结论…… 那么,科技小论文有没有质量标准呢?有。它必须具备“三性”=三种 要求 撰写科技小论文的方法和技巧。 这是编写科技小论文的技巧和方法:科技小论文是学生科学研究的总结,而不是文学作品。小论文的写法有一定的规范性,它包括以下内容: 1、论文题目:题目要与研究的内容相一致,不能文不对题。题目要求简洁、新颖、吸引读者。如《为什么咸蛋黄会出油?》这个题目简单明了,吸引读者。研究的题目不能太广,或过于深奥,不然无从下手。 2、引言:是论文的开场白,简单说明进行该研究的目的或作者是怎样想到要开展这方面的研究工作的起因。 3、材料和研究方法:要写清考察和观察对象、实验的材料及材料来源;采用什么研究方法以及具体研究步骤;使用了哪些仪器等,这都要如实交代清楚,以便经得起他人的重复试验。 4、结果:是论文的论据部分。除了用文字,还可用表格中的数据,图片,照片,这样具有说服力。数据的真实可靠是实验研究的关键所在。 5、讨论:这是论文的论证和论点部分。通过实验得出了什么科学结论。并要在理论的基础上加以说明。论点必须是以科学的研究方法和研究结果为依据,要恰如其分,实事求是。如果脱离实际,故意扩大研究成果,就失去论文的科学性,结果将会失去论文原本的真实性。 本次的科技小论文选题可以参考丛书的有关课题,通过观察、考察、实验等手段。也可围绕自己劳技创意和制作过程等方面内容进行论述。

为什么说贵阳是祖国的第二春城》一文开头:"我住在贵阳,常听人们说'昆明是春城,贵阳是第二春城'。至于为什么,我也弄不明白,我决心记录天气预报,看贵阳真是第二春城吗?"由常言产生验证其科学性的欲望。有些文章的问题是在偶然观察中产生、发现的,你也可以开头先根据时间顺序叙述其过程,再适时提出问题。正文即分析问题、解决问题部分。它包括对提出问题作出假设、观察、实验、考察过程、发现的现象、判断、推理得出结论等,这是小论文的核心部分。应注意的是:研究步骤要写得详略得当,实验过程、数据的来历、现象要写清楚,叙述时应有一定的顺序。数据材料要准确,可设计成能说明问题的表格、图解,必要时可附上拍摄的照片、采集的标本等,以增强说服力。获得的结论要有自己独特的见解,并且和论据保持一致性,论据要有严密的逻辑性。文字要简洁生动,层次清晰,条理分明。结尾小论文的结尾应写你得出的结论和对某一问题的建议。《蚯蚓的视力》一文结尾:"噢,我明白了,蚯蚓是不折不扣的瞎子,它是*嗅觉来寻找爱吃的食物,用感光器来辨别光的强弱。"以得出结论做为结尾,同开头提出问题相呼应,收到良好效果。小论文的初稿完成后,还要反复修改。看开头是否简明扼要,论据是否典型真实,论证是否符合逻辑,论点是否新颖一致,段落是否衔接自然,语言是否通顺准确等。改好后再让同学和老师帮助修改,逐步完善。巧克力对心脏有好处除了改善精神状态,近年来,巧克力的防病作用开始得到科学家的重视。最近,《美国药物杂志》发表的一篇论文称,巧克力、尤其是黑巧克力含有一种天然抗氧化剂黄酮素,能防止血管变硬,同时增加心肌活力、放松肌肉,防止胆固醇在血管内积累,对防治心血管疾病有一定功效。其实,这已不是科学家第一次提出巧克力的防病功效,希腊和德国也有过类似的研究。去年9月,英国权威医学杂志《柳叶刀》发表了美国的一份研究报告,指出巧克力可预防心脏病。美国加州大学的安德鲁·瓦特豪斯也发现:黑巧克力和红酒、水果、蔬菜一样,含有酚醛类物质(黄酮素就是其中一种),能杀死导致癌症和心脏病的受损细胞。日本的研究还表明:从巧克力中提取的酚醛类物质能提高血液的免疫力。前不久,据《美国临床营养学杂志》报道,意大利拉奎拉大学的研究人员做了一个试验:让15名健康人连续15天每天吃100克黑巧克力,结果发现,他们的血压有所降低,而对胰岛素的敏感度则得到加强。但是,志愿者们连续15天每天吃100克白巧克力后,就没有收到这样的效果。因此,医生们估计,黑巧克力对糖尿病患者可能有一定的帮助作用。另外,英国伦敦西敏斯特大学的克洛博士发现,巧克力可以预防感冒。他指出,巧克力的气味能促使男性免疫系统产生一种名为“免疫球蛋白A”的抗体,它可以对付身体上的各种“小毛病”如感冒等。除了这些实实在在的保健防病作用,科学家们还指出,巧克力中还含有多种营养成分,比如有抗氧化作用的维生素E、镁;人体必需的钾、铁和鞣酸等,对儿童大脑发育大有好处的卵磷脂;果仁、牛奶巧克力还会加入一些其他的营养成分。另外,巧克力的原料可可豆中含有大量黄烷醇,它也具有保健防病的作用。在科学家们的研究中,巧克力的一些“害处”也得到了澄清。研究发现,巧克力中的脂肪不会影响胆固醇水平。胆固醇正常的人在连续食用一个月的可可酱或纯巧克力后,胆固醇指标并未升高。此外,研究还表明,巧克力既不会引发粉刺和暗疮,也不会造成龋齿。专家们推荐多吃黑巧克力由于近年来对巧克力的认识和舆论宣传不断加深、更新,所以,在欧洲等地,巧克力的消费量明显上升。在法国,10年来巧克力的产量上升了33%,达40万吨。在人们对巧克力的关注程度不断上升的同时,黑巧克力开始唱起了“主角”。一个原因是在巧克力的保健作用中,它显得特别“突出”;另外一个原因就是,黑巧克力是含糖量和脂肪含量最低的巧克力之一。在法国,有81%的人将黑巧克力作为购买巧克力的首选。去年,由于媒体纷纷报道黑巧克力的保健作用,日本各大商场甚至出现了抢购的场面。尽管巧克力好处很多,但是,这世上毕竟没有十全十美的食品。对于巧克力,专家们的意见仍然是“适量食用”。本报驻法国记者在法国卫生部的网站上看到,食品卫生公告就是用“适量”一词来指导人们食用巧克力。在巴黎,一家名叫“可可与巧克力”的食品店的店主诺拉女士告诉记者,巧克力虽然营养丰富,但是,它的热量不低,每天的食用量最好还是控制在100克以内。本报驻加拿大记者的朋友、营养保健食品专家詹姆斯博士也持有同样的观点。他认为,巧克力含糖较多,肥胖者还是少吃为妙;一般人每天的食用量也别超过100克。还有专家认为,巧克力的营养成分不均衡,容易产生饱腹感,影响正常饮食,故儿童不宜多吃。而成人吃多了巧克力,也可能产生厌食、恶心、无力、抵抗力变差等“巧克力综合征”。

时下,许多人家用节能灯管换下日光灯管和白炽灯,但有一点要注意,在换灯管的操作中千万小心,别打破了灯管。无论灯管是新还是旧,打破都有毒。 日光灯、节能灯,都叫荧光灯。灯管内壁涂有荧光材料,管内装有汞蒸气和氩气。在一只40瓦的直管日光灯内含有约45~48毫克左右的汞。正常使用的荧光灯都是安全的,不会 对人体造成危害。若不慎打破了荧光灯管,灯管里的汞蒸气和有毒的荧光物质会迅速散布到室内空气中,会造成急性汞中毒。汞中毒,最初表现为一般性神经衰弱症状,如轻度头昏、头痛、健忘、乏力、多梦等,汞进入人体还会积累到肾、胸等组织和器官中,引起慢性汞中毒,出现精神症状,如性情抑郁孤僻而又急躁,易紧张激动与发怒而自己不能控制。手指、舌头、眼睛明显震颤,以手指及手部震颤最为突出。病情严重及病程长者牙齿松动并易脱落。 这算吗???

写科学小论文就是把自己在学科学、用科学的过程中看到、听到、想到的,经过整理、思考后将新的见解告诉大家。一篇科学小论文(以下简称小论文)应当包括论点、论据和论证三大要素。论点是小论文的灵魂,一般都以中心问题的形式出现,小作者围绕中心问题发表自己深刻而独特的见解。论据是为论点服务的,是为了使论点表述得更清楚明白而准备的事实材料。论证就是用论据证明论点的过程。科技小论文实际上是我们在课内外学科学活动中进行科学观察、实验或考察后一种成果的书面总结。它的表现形式是多种多样的:可以是对某一事物进行细致观察和深入思考后得出结论;可以是动手实验后分析得出的结论;也可以是对某地进行考察后的总结;还可以靠逻辑推理得出结论。那么,一篇高质量的科技小论文,要注意以下几点:一、选好课题撰写科技小论文,首先要考虑写什么,也就是课题的选择。选择课题是写好论文的关键。要注意以下原则:价值原则,即选题的理论价值和实用价值。要对其他的同学有启发、指导和参考的意义;可行原则,指主观和客观条件的可能性,即撰稿者个人的专业知识、理论修养、知识面、手头资料、实验条件、周围环境,不可贪大求深,应该量力而行;新颖原则,指课题应是他人未曾研究或研究过但未解决或完全解决,要注意“文贵创

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