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成都学纹绣价目表多少钱宜宾学做纹绣广安培训半永久 四川省哪里可以学习纹绣

自贡专业纹绣师Carbon dioxide is a potent greenhouse gas.二氧化碳是一种强力的温室气体。Levels of carbon dioxide, or CO2, in the atmosphere are increasing at an unprecedented rate.大气中的二氧化碳的浓度正在以前所未有的速度增长。But what impact do higher CO2 levels have on plants?但是空发中高浓度的二氧化碳对植物有什么样的影响呢?Plants use CO2 from the air along with sunlight and water to produce carbohydrates they use for energy.植物运用空气中的二氧化碳,与阳光、水一起产生能量所需的碳水化合物。This process is called photosynthesis.这个过程叫做光合作用。Higher atmospheric CO2 increases the rate of photosynthesis, and thus the amount of carbohydrates in plant leaves.二氧化碳浓度较高的大气增加了光合作用的速率,因此植物中碳水化合物的数量就会过剩。Sounds beneficial, right?听起来很有利,对吧?However, scientists have found that asCO2 levels go up, plant defenses might go down.然而科学家们发现随着二氧化碳浓度的升高,植物的防御将会降低。Researchers at the University of Illinois used a special open-air research facility that allowed them togrow soybean plants in different concentrations of CO2—without changing other factors such as sunlight, insects or rainfall.伊利诺伊大学的研究人员采用了特殊的露天研究设施,这些设施可以使他们在不同浓度的二氧化碳中种植大豆植物-不用改变其他的因素,如阳光,昆虫,或者雨水。They discovered that soybeans grown in fields with higher CO2 levels had much more insect damage and attracted more adult insect pests than those in plots with less CO2 in the air.他们发现在较高浓度二氧化碳中种植的大豆会遭受更严重的虫害,与在空气中二氧化碳浓度较低的地方相比,它们会吸引更多的成年害虫。The insects might have been attracted by the higher carbohydrate levels in the leaves of plantsgrown in high CO2.这些昆虫被植物叶子中由高浓度的二氧化碳产生的高含量的碳水化合物所吸引。But a higher carb diet wasnt the only thing that encouraged infestation.但是高碳水化合物的饮食并不是引起虫害的唯一原因。Normally, soybean plants under attack by insects will produce jasmonic acid.一般来说,被昆虫攻击的大豆植物都会产生抑制昆虫消化叶子能力的茉莉酸,This inhibits theinsects ability to digest leaves, which protects the plant from further attack.以保护植物免受进一步的损害。In high CO2atmospheres, the plants were unable to produce this defensive chemical.在高二氧化碳环境中,植物无法产生这种防御性化学物质。So, the dangers of rapidly increasing CO2 in our atmosphere might extend beyond climate change.所以二氧化碳急速增长所带来的危害可能远远不止气候变化。Since soybeans grown at higher CO2 would lose a crucial defense pathway and attractmore hungry beetles, other food crops might also be more vulnerable if CO2 levels continue torise.既然在高二氧化碳环境中种植的大豆会失去防御的关键通道并引来更多饥饿的甲虫,如果二氧化碳浓度继续升高的话,其它粮食作物可能也会变得更加脆弱。201410/336260成都/环亚纹绣培训学习绣眉纹眼多少钱 攀枝花学韩式雾状眉多少钱

成都国际纹绣培训半永久性化妆漂唇术培训Remember seesaws? Those things were great.还记得跷跷板吗?它可是伟大的发明,But there wasoften a problem.但仍然存在一个问题。Suppose theres a big kid on one side and a smaller kid on theother side.假设跷跷板的一边坐一个大点的孩子,而另一边坐一个 小点的孩子。The seesaw just stays in one position:跷跷板就只停留在一边:big kid on theground, smaller kid up in the air. No fun.大孩子那边,小孩子则悬在空中。这样就失去了跷跷板的乐趣。After a few differenttries, you probably realized that moving the big kid in towardthe center made it possible to rock a little.几次尝试后,你也许会发现让大孩子往中间坐久可以摇动一点。Move the big kid evenmore and you can achieve balance.Now the seesaw works.再让大孩子让中间挪动直至平衡后跷跷板就可以摇动了。Whats going on here?这到底是怎么回事?The answer is in the “center of mass.”就是“质心”。The center of mass is a pointsomewhere along the plank that holds the two kids where their average weight falls.质心是跷跷板上撑两个孩子平均重量的一个点。If you can getthe center of mass to be over the pivot point, the seesaw will be balanced.如果找到了是新的点,跷跷板就平衡了。Theres a simple way to figure out where the center of mass is.有一个简单的方法找出质心。If the big kid is two times as heavyas the little kid, then their mutual center of mass will be two times closer to the big kid than to thelittle kid.如果大孩子的重量是小孩子的2倍,那么质心的位置离大孩子的距离就比离小孩子距离近2倍。Three times heavier and the center of mass will be three times closer. And so on.重三倍,质心的位置就进三倍,以此类推。So the reason the heavy kid sits on the ground while the light kid is up in the air is that theirmutual center of mass is on the heavy kids side of the pivot.因此,重的小孩坐在地上而轻的小孩悬在空中的原因是,他们共同的质心在重的孩子这边。To make the seesaw work, theheavy kid must push that center of mass forward until it just touches the pivot.要想让跷跷板摇动,重的孩子就得往中间挪直到质心移到中心。Then theiraverage weight pushes right on the middle, letting the ends rock up and down.然后当他们的平均质量正好在中间,这样两头就可以上下摇动了。 /201410/338530 For decades, circumstances forced me to talk almost exclusively of peace.数十年来,迫于形势,我只能谈和平。But now, he told the journalists,the news had to be presented so as to create the impression that...但现在他告诉记者必须通过新闻来制造假象。There are matters which, if they cannot be achieved by peaceful means,must be enforced by means of violence.若一些事端不能通过和平方式解决则必须使用暴力。What was crucial was to say to the people...重要的是要告诉人民领导人永远是正确的...This was now important, said Hitler,in order to free the German people from the bondage of doubt.希特勒说,当前这点尤为重要,唯有这样,能让德国人摆脱疑虑。These were the scenes in Munich, in July 1939,for a celebration of German art.这是1939年7月,慕尼黑庆祝德国艺术节的场景。By the time these pictures were taken,Hitler had orchestrated the dismemberment of Czechoslovakia,and the British and French governments had warned Hitler that if the Germans moved on Poland, then there would be war.庆祝期间希特勒已策划进军捷克斯洛伐克,英法政府警告希特勒,若德国进军波兰,势必引发战争,德国媒体对此事的态度则大相径庭。The German press saw things very differently and with one voice had been telling the people that Germany was being treated unjustly.口径一致地向人民宣传德国受到了不公平待遇。That their Fuehrers legitimate demands were simply not being met.元首的合法要求没得到满足。 译文属201605/442052绵阳首秀美容纹绣培训学习半永久化妆PCD纹绣多少钱成都/素秀国际学校做专业绣眉多少钱




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