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"With the changes in temperature vectors - disease vectors like mosquitoes have been reported to cause malaria in places that had never reported malaria cases,".
VOA: standard.2010.01.02
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And temperature then is associated with property And if it had changed, then the temperature between those two would have changed in a very particular way.
就与这种性质有关,如果它发生了改变，说明这,两者的温度,以特定的方式发生了改变。
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So, all I want to do now is look at the derivatives of the free energies with respect to temperature and volume and pressure.
我现在所要做的一切就是,考察自由能对,温度，体积和压强的偏导数。
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"It was a very simple wooden table with a fitted bulb that would adjust based on the baby's temperature, and had it constructed and implemented in her hospital.
VOA: standard.2009.12.18
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So temperature in Fahrenheit maybe with a space, just to get the aesthetics to look a little interesting.
华氏温度可能用一个间隔来，使其更加美观和有趣。
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Some of the challenges that you see here I mentioned before, so there are problems with drought, with pests, with temperature changes and the like.
我之前提到的,你们所见的这些挑战,如干旱问题,虫害问题以及温度变化之类的
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And then they found that they could freeze-dry this preparation of virus, and freeze-drying to lower the temperature, freeze it, then extract out all the water, so you're left with a powder, basically a powdered form of the virus, that could be shipped all over the world, and then reconstituted by adding water to it.
研究者们发现可以冷冻干燥这些病毒制剂,冷冻干燥就是就是降低温度,冷冻病毒,然后提取出所有水份,然后就剩下一些粉末,这主要是粉末状的病毒,这样就能将它运往全世界,并可以通过加水来恢复病毒的活性
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We know how the volume and temperature vary with respect to each other at constant pressure.
知道在恒定压强下,体积如何随着温度变化。
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You know how pressure changes with temperature at constant volume if you know the equation of state.
如果你知道状态方程,知道在体积恒定的时压强如何随着温度变化。
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T2 Is the temperature T2 in this process smaller or larger than if I were to do the process reversibly with the same endpoint pressure.
这里的末态温度,与经过可逆绝热过程,到达相同压强的末态温度相比哪个比较高呢？
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Now these quantities were useful because you could relate them. The slope of changes, with respect to volume or temperature of the energy with respect to quantities that you understood, that you could measure.
去得到这些量,这些量很有用，而且你们已经知道了，怎么把它们相互联系起来,像这种比例形式的量，能量比上温度或体,或其它你们懂的可以测量量。
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And then we can take the derivative with respect to temperature, it's just R over molar volume minus b.
这样我们求,压强对温度的偏导数，结果等于R除以摩尔体积V杠减去b的差。
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And if you go back into the 1800's when thermodynamics was starting, there were a zillion different temperatures scales Everybody had their own favorite temperature scale The one that we're most familiar with is the centigrade or Celsius scale where mercury was the substance, and the volume of mercury is the property.
如果你回头看看19世纪温度计,刚开始使用的时候，那时有不计其数的不同温标,每个人都有他们自己最喜欢的温标,我们最熟悉的是,摄氏温标，用水银,作为工作物质，水银的体积是所用的性质。
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In other words, the order of taking the derivatives with respect to pressure and temperature doesn't matter And what this will show is that dS/dp dS/dp at constant temperature, here we saw how entropy varies with volume, this is going to show us how it varies with pressure.
换句话说,对温度和压强的求导顺序无关紧要,结果会表明,恒定温度下的，对应我们上面看到的，熵如何随着体积变化，这个式子告诉我们，熵如何随着压强变化。
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It's just how much heat is involved when we change the temperature. Now, the products have some heat capacity associated with them right, it takes a certain amount of heat if we make their temperature change, to either put it in or take it away, depending on which direction the temperature is changing.
问题就是当我们改变温度时,有多少热量发生了转移,生成物具有一定的热容,如果我们改变,它们的温度，就要输入或,提取一定的热量,这取决于温度改变的方向。
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You take your room temperature liquid helium and you cool it with liquid nitrogen to 77 degrees Kelvin, the new, you're not quite there yet 77k unfortunately right? Then you take hydrogen you cool it would liquid nitrogen to 77, then you can use your hydrogen gas.
首先要有常温的氦气,拿液氮把它冷却到77k，那个新来的7,你不坐在那儿，对吧？,然后用液氮把氢气降温到,然后就可以使用这个氢气了，想要用氢气来做焦耳-汤姆孙实验。
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du/dT constant pressure is the direct derivative with respect to temperature here, which is sitting by itself under constant volume keeping this constant but there is temperature sitting right here too.
偏U偏T，p恒定是对,温度的直接微分，而它本身对体积不变,保持它不变，但是这里也有一个温度,这就是偏U偏V，T恒定。
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So in this experiment here, delta p is less than zero. You need to have this whole thing greater than zero. So delta T is less than zero as well. So if you're below the inversion temperature and you do the Joule-Thomson experiment, you're going to end up with something that's colder on this side than that side.
所以在这个实验中，Δp小于零,这全部都大于零,因此ΔT也小于零,所以如果在低于转变,温度的情况下做焦耳-汤姆孙实验,最后的结果是,这边的温度比这边低。
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