He said the first 72 hours are critical in saving survivors, and he is still holding out hope for both Haitians and U.N.
VOA: standard.2010.01.14
.. I started out with the equally-weighted-- I was talking about stocks-- about n stocks that all have the same variance and are all independent of each other.
开始的时候我讲了等权重的-,我开始时讲了股票-,几支拥有相同方差的股票,彼此间相互独立。
And an electron is something where, i n fact, we might be able to, if we calculate it and see how that works out, actually observe some of its wave-like properties.
如果我们对电子做计算,并且知道如何算出来的,那么我们是可以观测到,电子的一些波动性质的。
The U.N.top climate official, Yvo de Boer reminded delegates they have their work cut out.
VOA: standard.2009.12.09
It turns out there's a new function strlen S-T-R-L-E-N that you probably have not used yet called strlen, S-T-R-L-E-N, programmers early on and still like to be succinct but communicates sufficiently what they mean.
结果这里有个新的函数,你可能没有使用过,叫做,早期的和现在的程序员喜欢简洁地,但是能充分的传达他们的意思。
The U.N.'s Yvo de Boer issued a stark reminder that the clock has run out.
VOA: standard.2009.12.08
n*pi/L It turns out it is n pi over l.
结果是。
Pachauri has ruled out stepping down as head of the U.N.panel.
VOA: standard.2010.01.23
And then one of the things that I suggested was that if we could figure out some way to order it, and in particular, if we could order it in n log n time, and we still haven't done that, but if we could do that, then we said the complexity changed a little bit.
这就涉及到了排序,如果可以想出一种来将其进行排序,甚至可以在n,log,n的时间内完成,虽然目前我们没做这件事,但是一旦开始做这件事,那么复杂性就是发生一些变化。
The talks taking place this week in Barcelona will be the last before a major U.N.summit in December where delegates will hash out a new deal to replace the Kyoto Protocol.
VOA: standard.2009.11.04
So if you're trying to make a more complicated organic molecule carbon-carbon bonds are one of the most difficult things to make in organic chemistry, and it turns out that c n minus is a very reactive molecule, so it's a good way, even though we'll go over some drawbacks in a second, it is a good way to make carbon-carbon bonds.
如果你要合成一个更复杂的有机分子,碳碳键是有机化学中,最难制造的键之一,而实际上氰离子是一种具有很高活性的分子,用它是一个好办法,尽管我们一会儿将看到它的一些缺点,但它的确是一个制造碳碳键的好方法。
The Palestinians say they decided to take the matter of statehood to the U.N.Security Council out of frustration that 16 years after the signing of the Oslo accords there is still no peace agreement.
VOA: standard.2009.11.16
So, it turns out that n is not the only quantum number needed to describe a wave function, however. There's two more you can see come out of it.
事实上,n不是描述一个波函数需要的,唯一的量子数,你们可以看到,还需要,两个量子数。
We'll get to discussing that, but what I want to point out here again is the fact that instead of just being dependent on n, the energy level is dependent on both n and l.
我们将要讨论它,但是我想指出的是事实上能级不只是与n有关,而是与n和l都有关系,而且n不再是。
So instead you'd have to maybe if you start with wavelength, go over there, and then figure out velocity and do something more like kinetic energy equals 1/2 n b squared to get there.
这时你要先从波长开始,到这,然后算出速度,然后像动能等于1/2nb平方得到这。
psi So we're going to for psi, and before that, we're going to figure out that instead of n just that one quantum number n, we're going to have a few other quantum numbers that fall out of solving the Schrodinger equation for what psi is.
我们要讲到,但在这之前,我们已经知道了,主量子数,现在我们需要知道,其他一些,解psi的薛定谔方程,所需要的量子数。
So there are two electron configurations in the n equals one shell, if we follow according to the selection rules that we spelled out last day.
如果根据上次课,我们阐明的原子光谱选择定则,我们就会知道在n等于1的那一层,有两种电子图像构型。
So what we'll do is this problem here, which is let's calculate out what the wavelength of radiation n would be emitted from a hydrogen atom if we start at the n equals 3 level and we go down to the n equals 2 level.
我们来做这个问题,让我们来计算一下,从n等于3到,等于2能级氢原子辐射的波长是多少。
And we can generalize to figure out, based on any principle quantum number n, how many orbitals we have of the same energy, n and what we can say is that for any shell n, there are n squared degenerate orbitals.
我们可以总结出来,在,主量子数为n的情况下,同一个能量上,有多少个轨道,我们可以说,对任何壳层,有n平方个简并轨道。
I was just finding very tunnel vision-like, the smallest elements at that moment in time which means I don't know anything about the other elements other than they are not the smallest and so no matter what with Selection Sort I had to repeat this again and again and again and if you do out the math it's roughly N squared steps in the worst case as well.
我只有一个狭窄的视野,只知道某时刻的最小元素,就意味着我并不知道其他元素的任何情况,只知道它们不是最小的,所以不管怎样,在选择排序中,我就得一遍一遍地重复选择过程,在最坏情况下,大概需要N的平方次比较。
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