Saturday,the Canadian,24,said he fed off the energy of the thousands of Canadian fans who flooded the downtown area the night before his race.

VOA: standard.2010.02.28

So if we have a negative change in energy for any reaction as it's written, what that actually means is we're giving off energy as the reaction proceeds.

如果我们像这里写的这样,在任何一个反应过后，得，到的能量变化为负值,这就意味着我们在这个过程中放出了能量。

麻省理工公开课 - 化学原理课程节选

And instead of having the electron giving off energy as a photon, instead now the electron is going to take in energy from light and move up to that higher level.

与电子以光子形式施放能量不同,我们现在要从光中,获得能量到一个更高的能级。

麻省理工公开课 - 化学原理课程节选

"I heard the brushing-off ritual gets rid of all the harmful energy from my body,"

VOA: standard.2010.01.01

And when it falls back down that energy is given off.

当它回去的时候,它的能量也消耗殆尽了。

麻省理工公开课 - 固态化学导论课程节选

The Democrats say all this American energy is off limits."

VOA: standard.2009.05.23

So it's going to keep in mind the limitations, so let's start off with talking about ionization energy.

那么让我们将这些局限性记在心里，继续来讨论一下电离能。

麻省理工公开课 - 化学原理课程节选

"Someone could attack the industrial control systems that control all the valves, all the distribution systems, and are used to turn on and off various aspects involved with energy and the electrical power grid and oil and gas distribution networks,".

VOA: standard.2009.08.11

That makes sense because we're losing energy, we're going to a level lower level, so we can give off that extra in the form of light. And we can actually write the equation for what we would expect the energy for the light to be.

这很合理，因为我们在损失能量,我们要到一个更低的能级去,我们要以光的形式给出额外的能量,我们可以写下光能量的方程。

麻省理工公开课 - 化学原理课程节选

And what we predict as an energy difference between two levels, we know should correspond to the energy of light that's either emitted, if we're giving off a photon, or that's absorbed if we're going to take on a photon and jump from a lower to a higher energy level.

我们预测，两个能级之间的能量差，我们知道，它要么和发出的光有关,如果它发出光子的话，要么它吸收光子,从低能级跃迁到，更高能级上去。

麻省理工公开课 - 化学原理课程节选

At infinity, there's no stored potential energy, and it drops off more and more negative as one over R.

在无限远处，没有储存的势能，并且它向负方向减少，当距离超过R时。

麻省理工公开课 - 固态化学导论课程节选

So that's why we're giving off extra energy.

这也就是我们放出多余能量的原因。

麻省理工公开课 - 化学原理课程节选

So, one thing they did, because it was so easy to measure kinetic energy of electrons, is plot the frequency of the light against the kinetic energy of the electron that's coming off here. And in your notes and on these slides here, just for your reference, I'm just pointing out what's going to be predicted from classical physics.

他们做的其中一件事,因为测量电子动能是很容易的，就是画出光的频率,和出射电子动能之间的关系,在讲义的这里，仅仅是,为了做个比较，我要指出，经典物理所给出的预测,这个不作为对你们的要求。

麻省理工公开课 - 化学原理课程节选

we start high and go low, we're dealing with emission where we have excess energy that the electron's giving off, and that energy is going to be equal the energy of the photon that is released and, of course, through our equations we know how to get from energy to frequency or to wavelength of the photon.

当我们从高到低时，我们说的,是发射,电子有多余的能量给出，这个能量等于，发出,光子的能量，当然我们可以通过方程,从能量知道，光子的频率，和波长。

麻省理工公开课 - 化学原理课程节选

So z equals 7 -- this is the cut-off where, in fact, the sigma orbital is going to be higher in energy than the pi 2 p orbitals.

所以z等于7-这是分界点，实际上，sigma轨道能量,要比π2p轨道高。

麻省理工公开课 - 化学原理课程节选

z And what you need to remember is if the z 8 is equal to eight or greater, such as oxygen being the cut-off point, this sigma 2 p orbital is actually lower in energy than the pi 2 p orbitals, the molecular orbitals.

你们要记住如果,等于或者大于，就像O是分界点，这时sigma2p轨道,比π2p轨道能量更低。

麻省理工公开课 - 化学原理课程节选