The method combines an examination by positron emission tomography with a drug that lights up beta-amyloid.

VOA: special.2011.02.08

who conducted the experiment of hydrogen emission spectrum in a magnetic field.

塞曼做了一个,磁场中的氢原子光谱实验。

麻省理工公开课 - 固态化学导论课程节选

So, let's say we're looking at an element and we have an emission spectra, and we know that it has five distinct different kinetic energies in that spectrum.

比如我们正在研究一个元素,而且我们得到了它的光谱，知道了在它的光谱里,有五个分立的动能。

麻省理工公开课 - 化学原理课程节选

"Nobody else has been able to observe, with the detail that we can, the infrared emission from galaxies."

VOA: standard.2009.05.14

Radiation is the emission of energy.

辐射会发出能量。

麻省理工公开课 - 固态化学导论课程节选

In Copenhagen, experts and officials alike are putting the emphasis on what people and governments can do to cut the emission of greenhouse gasses.

VOA: standard.2009.12.09

And when we talked about that, what we found was that we could actually validate our predicted binding energies by looking at the emission spectra of the hydrogen atom, which is what we did as the demo, or we could think about the absorption spectra as well.

当我们讨论它时，我们发现,我们可以通过,观察氢原子,发射光谱，来预测，结合能，就像我们在演示实验里做的那样，或者我们也可以观察吸收谱。

麻省理工公开课 - 化学原理课程节选

"Now the question arises whether we can quantify it into a precise emission reduction targets number.

VOA: standard.2009.11.27

Absorption is just the opposite of emission, so instead of starting at a high energy level and dropping down, when we absorb light we start low and we absorb energy to bring ourselves up to an n final that's higher.

吸收就是发射的逆过程,与从一个高能量到低能量不同，当吸收光时，我们从低能量开始,吸收能量到一个更高的能量。

麻省理工公开课 - 化学原理课程节选

The State Council said the country will reduce its "carbon intensity" by 40 to 45 percent by the year 2020,as compared to 2005 emission levels.

VOA: standard.2009.11.26

Photon emission, perhaps.

光子发射，可能。

麻省理工公开课 - 固态化学导论课程节选

But observers say India and China remain wary of accepting legally binding emission cuts at a time when they are making their presence felt on the global economic scene.

VOA: standard.2009.11.27

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

Tiziana Bonapace,a senior economist with the UNESCAP, says developing countries need financial aid to assist them in developing low-emission technologies and agriculture methods and ensuring poverty reduction policies are maintained.

VOA: standard.2009.09.01

So what we need to do here is use the Rydberg formula, and actually you'll be given the Rydberg formulas in both forms, both or absorption and emission on the exams.

我们需要用到Rydberg公式，事实上，在考试时,我们会给你们Rydberg公式的两种形式。

麻省理工公开课 - 化学原理课程节选

The company says its goal is to generate electricity from natural,non-edible, renewable and sustainable resources indigenous to West Africa with projects that focus on reducing the emission of greenhouse gases.

VOA: standard.2009.09.13

So let's do a sample calculation now using this Rydberg formula, and we'll switch back to emission, and the reason that we'll do that is because it would be nice to actually approve what we just saw here and calculate the frequency of one of our lines in the wavelength of one of the lines we saw.

让我们用Rydberg公式,做一个例题，我们回到发射上,这么做是因为这样,可以用我们看到的波长,来验证我们计算的频率。

麻省理工公开课 - 化学原理课程节选

John Pershing,Washington's deputy special envoy for climate change, says President Obama supports U.S.emission reductions comparable to the European Union and Japan, but wants legally binding commitments from other countries as well.

VOA: standard.2009.09.28

Clinton,who insisted India can make emission cuts without harming its economy, said she is optimistic the two governments can reach a common approach before the world conference on climate change in Copenhagen in December.

VOA: standard.2009.07.20