时间:2018年06月24日 20:31:55

Bees play a crucial role on Earth-some even claim that if they go extinct,humanity would be next.So with the dramatic decline in bee population,should we be worried? What happens if the bees all die?蜜蜂在地球上扮演着重要的角色----甚至有人说如果蜜蜂灭绝了,下一个说是人类,所以,如今迅速减少的蜜蜂数量,是否值得我们担忧?如果蜜蜂灭绝会如何?Simply put,if a plant produces a flower,you can bet that bees help them reproduce.This long-standing,working relationship evolved with flowers being bright and fragrant to attract bees,and the bees fuzzy,velcro-like bodies helping them to efficiently transfer pollen from the male part of the plant to the female part.简而言之,如果一棵植物开了一朵花,那么蜜蜂肯定会帮它们繁殖,自古以来,它们有着固定的分工,花儿负责开得娇艳芬芳吸引蜜蜂,而蜜蜂那长着毛像魔术贴一样的身体则负责,将植物的花粉从雄花上移到雌花上。This seemingly simple mechanism is directly responsible for the production of 70% of fruits,vegetables,seeds and nuts that we consume on a daily basis.70% !Which translates into almost 0 billion in global agriculture revenue.This huge responsibility is accomplished by droves of commercial bees,reared by professional beekeepers for the sole purpose of being transported to farms and orchards to pollinate crops.这个看似简单的机制正是,70%水果,蔬菜,种子和坚果生产的直接原因,而这些食物是我们的日常所需,70%!就全球农业收益而言,相当于2000亿美金,这个巨大的收益是由一群商业蜜蜂完成的,专业养蜂人唯一的饲养目的就是,桨它们送去农场和果园为庄稼授粉。But since 2006,these hardworking,busy bees have been mysteriously disappearing.This Colony Collapse Disorder has seen an average of 1/3rd of commercial bees abandoning their hives.In fact,some beekeepers have even reported that 90% of their bees have simply buzzed off.In some colonies,mites,viruses and parasites have been to blame,but many are now looking at a class of insecticides called neonicotinoids.但是 2006年之后,这些勤恳忙碌的蜜蜂不知如何故不断消失减少,蜂群衰竭失调症导致,约三分之一的商业蜂抛弃了它们的蜂房,事实上,有养蜂人报告说,他们蜂房90%的蜜蜂都跑掉了,有些蜂群出问题,是因为螨虫,病毒和寄生虫,但是更多地方可能是受头号杀虫剂新烟新烟碱的影响。This neurotoxin is used to kill off crop eating insects and pests,but also affects the central nervous systems of bees when they consume contaminated nectar.And since nectar is brought back to hives,the entire colony can be affected,leading to mass confusion and disorientation.这种神经毒素被用于消灭吃庄稼的虫子和害虫,当蜜蜂吸食了被它污染的花蜜时,中枢神经系统就会受影响,花蜜被带回蜂房后,整个蜂群都会受影响,导致大规模的混乱和迷失方向。On top of this,other factors such as extremely cold and long winters,a lack of genetic diversity in commercial bees,and less variable nectar in the fields may be at fault.If the trend continues,entire food chains and webs may be at risk.Take almond planets for example;the hulls of these nuts are used as feed for farm cattle and chickens.另外,其他因素,例如极其漫长的严冬,商业蜂群缺少遗传多样性,田里花蜜种类单一都可能会造成问题,如果继续发展下去,整个食物链食物网都会出问题,以杏仁植物为例,这些坚果的外壳,过去曾用于喂养农场里的牛和鸡。Fewer bees means fewer almonds,which could mean declining livestock,and ultimately less milk,cheese,eggs and meat production.Not to mention almonds are used in cereal,baking and many other food products.Beef and dairy cows would also be harshly affected by the vanishing alfalfa fields which are used to harvest hay for cattle.蜜蜂减少杏仁花也会减少,这意味着家畜也会减少,最终牛奶,奶酪,鸡蛋和肉类都会减少,更不用说,杏仁还广泛用于谷物,烘焙和许多其他食品生产过程,苜蓿田的消失也会大大影响肉牛和奶牛,这种植物收割晒干后用于养牛。Looking for a morning buzz?Considering bees pollinate Coffea arabica,whose seeds we grind for coffee,you can count that out.Without bees,our diet would consist of mostly corn,wheat and rice,as they are wind pollinated plants.Like your clothes?Not only is cotton the biggest cash crop in the US,it also makes up about 35% of the world#39;s fiber use.So you can forget those blue jeans,towels,mattresses and high quality paper products.在找清晨活力?考虑到咖啡树是靠蜜蜂传份的,猜猜我们用来磨咖啡的豆子是谁的种子,没有了蜜蜂,我们的主要食物会是玉米,小麦和米饭,它们都是风媒传粉植物,喜欢你的衣物?棉花不仅是美国最重要的经济作物,它还是世界上35%纤维制品的原料.以后就不用惦记牛仔裤,毛巾,床垫,和高品质的纸制品了。Simply put,we#39;d be living in a completely different world without bees,not to mention suffering a substantial economic strain from their disappearance.So while we may not necessarily go ;extinct; should the downward trend persist,a world without the buzz of bees would definitely...sting!简而言之,没了蜜蜂,我们会生活在一个截然不同的世界,更别提蜜蜂消失带来的巨大的经济压力,因此,虽然继续让蜜蜂消失,我们也未必会灭绝,但是一个没有蜜蜂的世界,绝对会让人相当痛苦。 Article/201504/371200

Hi, I#39;m Jessic嗨 我是JessicaAnd today, I#39;m going to be talking about a chemical demonstration今天我要讲的化学演示I like to call ;Money to Burn;叫作;烧钱;and chemist Dr. Bassam Shakhashir化学家Bassam Shakhashiri士here he is这就是他is actually going to be showing us the dem将为我们进行这个演示He#39;s the president of the American Chemical Societ他是美国化学学会主席and is performing this demo right here at MIT他在我们MIT进行了这个演示Let#39;s see if he has some money to bur看看他是怎么烧钱的What I#39;m going to do now i下面我将I#39;m going to reach in here, I#39;m going to take a dollar bil从钱包里拿出一张美钞and I#39;m going to put it into flame just like that像这样把它放到火焰里Was that too fast?这是否太快了What we always do in science is repeat the experiment在科学里 我们总喜欢重复实验So I think although it looks like a dollar bill它虽然看起来像美钞it#39;s not a real dollar bill但不是真正的美钞I bring it close to the flame我让它靠近火焰It disappears into thin air. It looks like magic, right?它瞬间消失掉了 这很像魔术 不是吗I love magi我很爱魔术Magic is engaging魔术很迷人but not informativ但说明不了问题How is that dollar bill burning up so quickly?那张美钞是如何快速燃烧掉的Well, it#39;s actually not a dollar bil实际上 它不是一张美钞It#39;s called flash pape而是一张闪光纸And it#39;s paper that has been treated with chemical这种纸用化学药剂处理过to make it burn quickly and leave no ashes让它能够快速燃烧 而且不留灰烬Now flash paper has been nitrate闪光纸被硝化过Practically what that means is tha实际也就是you soak the paper in a mixture of concentrated nitric and sulfuric acid将纸张浸入到浓的硝酸硫酸混合物中The cellulose in the paper then reacts with the aci纸张中的纤维素会同酸反应to produce nitrated cellulose and wate生成硝化纤维素和水The reaction is this反应是这样的So our nitric acid her这是硝酸mixes with the cellulose同纤维素反应Now this is actually just one unit in the big polymer that is cellulos这其实只是纤维素大聚合物中的一个单元It#39;s got lots of little units of C6H10O5纤维素包括很多单元So in this equation, I#39;m only writing one unit而这个方程中 我只写了一个单元And that#39;s creating nitrated cellulose and wate这会生成硝化纤维素和水Now the nitro group, the NO2, is the reactive grou硝基NO2是活性基团and it can be very reactive depending on the molecule that it#39;s in在有些分子中时 它的活性会非常高You#39;ve no doubt heard of nitroglycerin你们肯定听说过硝酸甘油which looks like thi它是这样的It#39;s an explosive liquid它是一种爆炸性液体Or TNT还有TNTwhich actually stands for trinitrotoluene全称是三硝基甲苯It looks like thi它是这样的So all of these molecules have nitro group in them所有这些分子中都有硝基And it#39;s the nitro or NO2 groups that make these molecules explosiv正是硝基NO2让这些分子具有爆炸性Now let#39;s watch what happens when Dr. Shakhashiri tries this again下面再来看Shakhashiri士的第二次尝试but this time with a real dollar bil不过这次 他将用到真正的美钞I#39;d like someone in the audience to我想问某位观众let me borrow from them a real one dollar bill借一张真正的一美元钞票Is there someone in the audience who would let me在座各位谁愿意who would trust me with a real one dollar bill?借一张一美元钞票给我吗Or a five-dollar bill五美元钞票也行Steve, how about a twenty-dollar bill, ha? Steve有二十美元钞票吗You#39;ve got a twenty-dollar bill?有二十美元钞票吗Okay, here#39;s one-dollar bill好的 一美元钞票It#39;s a real one dolla货真价实but you don#39;t know what I#39;m going to do with it, don#39;t you?你不知道我会拿它做什么 Article/201412/349951

It#39;s a pretty baffling series of names and places.这一大串人名和地名确实有点儿让人头晕。But if you#39;re a historian trying to reconstruct the society and the religion of ancient Yemen, pretty well all you have to go on is inscriptions like this one.但历史学家重建古代也门社会与宗教信仰的工作几乎全部建立在这样的铭文上,它们的信息量很大。There are about 10,000 of them known, each one, it has to be said, more opaque than the other.大约每个都有10000,不得不说,一个比另一个更晦涩难懂。But if you actually unpick the inscription on this hand, it does in fact contain a great deal of information.但是如果你真正破解出铭文后,它实际上包含大量的信息。From it we learn that this bronze hand was dedicated at the temple of the god Ta#39;lab Riyam, in a place called Zafar, high in the Yemeni hills.专家破译出文字后,我们了解到,这只手曾被供奉在也门山丘高处一个叫萨法城的地方的塔拉布里阳神庙里。The owner of the hand, Wahab Ta#39;lab, tells us that he belongs to a clan, and that that clan in turn is part of a larger tribal organisation, whose god was Ta#39;lab.手的原主人瓦哈塔拉布来自某个部落,而这个部落属于一个规模更大的、信奉塔拉布神的族群。So, Wahab Ta#39;lab had obviously been named after his own god.因此, 塔拉布的名字显然来自他所敬拜的神祇。And as a further sign of faith he#39;s dedicated his hand publicly to Ta#39;lab, at the centre of the city of Zafar, where it would have been seen along with other offerings of gold, bronze or alabaster, representing human figures, animals, arrows, spear heads, that sort of thing.为了表现虔诚,他将自己的手公开献给萨法城中心的神庙,与人们献上的其他供品摆在一起,其中包 括塑造成人、动物、弓、箭头等形象的金、铜与雪花石奇制品。But in return for these offerings, the god Ta#39;lab was expected, in general terms, to see the donors alright.供奉者希望神能够赐福他们作为回报。But Wahab Ta#39;lab must have been pretty alright to start with, only a man of real wealth could offer a bronze hand as beautifully made as this.但瓦哈塔拉布一定相当富有,只有富人才能供奉如此精美的青铜手。But, by the international standards of the day, his whole society was wealthy.不过按照当时的国际标准,他整个族群的成员都很富有。At the time of our hand most of south Arabia was effectively one state-a confederation of tribes like Wahab Ta#39;lab#39;s, known to historians as the Himyarite kingdom.青铜手制作时期,几乎整个阿拉伯半岛南部都属于一个国家,一个由类似塔拉布所属族群所组成的城邦联合体,历史学家称之为希米亚里特王国。 Article/201507/387051

栏目介绍:搞笑英语轻松学通过不同的搞笑生活片段来学习日常口语,领域涉及生活的各个方面,让我们边看视频边学英语。正宗地道的口语,假一罚十。美剧电影真人秀都看过了之后还能看什么学口语呢?当然是看这些双语视频啦!又好玩,又原汁原味,又顺便学一两句地道英语,多痛快!快来看看吧! Article/201511/407218

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