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We use here a low temperature fired clay, which is very easy to work with.
VOA: special.2009.09.09
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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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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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They were prepared at the same temperature as meat with the marinade mixes.
VOA: special.2010.06.01
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It's going to have some volume, temperature to begin with, and then we're going to do something to it.
气体有一定的，体积与温度，现在我们。
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Aspirin competes with many other medicines for reducing pain and high body temperature.
VOA: special.2010.12.14
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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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People with malaria develop a high body temperature.
VOA: special.2010.04.20
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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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"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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"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, 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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dS/dV And that, now, we know must equal dS/dV, with a positive sign. At constant temperature.
我们知道这个等于恒定温度下的，符号为正。
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I want to cool a gas with a Joule-Thomson experiment, what temperature do I have to be at?
给气体降温时,需要到达什么温度？
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That is, most processes that we're concerned with, they'll happen with something held constant like pressure or temperature or maybe volume.
这句话是说我们所关注的大部分过程，发生的时候都是保持某个量为常数,比如压强，温度或者体积。
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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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Because so much of what we do in chemistry does take place with constant temperature and pressure.
因为化学中我们所做的很多东西,都是在恒定的温度和压强下进行的。
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That is, it's easy to write down straight away that dG with respect to temperature at constant pressure S is minus S.
这就是说，可以很简单的写出dG在,恒定压强下对温度的偏导数,是负。
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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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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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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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This is real, unlike the Joule coefficient which is very small so that most gases have tiny Joule coefficients. So if you do a Joule experiment, you hardly measure a temperature change. With real gases, here you do actually measure it. You can feel it with your finger on your bicycle tire.
系数那样小以至于,大多数气体的焦耳系数,都很小，所以如果你做焦耳实验,很难测量出温度的变化,对于真实气体，你可以测量它，你能通过手指按在,自行车轮胎上来感觉到它。
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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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Therefore, from experiments, u is only a function of temperature for an ideal gas, H and therefore from these experiments, 0 we come out with delta H dH/dp is equal to zero.
因此，从实验可以得出,对于理想气体u只是温度的态函数，因此从这些实验中我们得到Δ,偏H偏p等于。
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Let's say we start from some V1 and p1 here, so high pressure, small volume and we end up with a high volume low pressure, under constant temperature condition.
例如我们要从压强比较高，体积比较小V1，p1出发,到达低压强，大体积的末态，过程中温度不变。
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pV Also A plus pV and G is minimized at equilibrium with constant temperature and pressure.
同时等于亥姆赫兹自由能A加上,同时在恒定的温度和压强下。
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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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