I showed you the distance between the letters 'A' and 'Z', between day and night."
VOA: special.2009.03.28
That statement says, get the value of x, which is this link, and give z a pointer to the same place.
这个声明的意思是,取得x的值,也就是连接指向的值,然后给z赋予一个指向同样位置的指针。
The first one uses something called Z a compressibility factor, z.
下面我们就来看几个例子,第一种办法是引入压缩系数。
"The book is Darwin's Universe: Evolution from A to Z, and it is a life's work,"
VOA: standard.2009.11.25
Yeah, I've still got a binding for z and I'm giving it the same test, but notice now I've got the two same commands but they have different indentation.
对,我还是对z进行了绑定,我还是要对它进行同样的测试,但是请注意现在我有了两个同样的命令,但是它们有不同的缩进。
Specifically, it's always the z that forms the sigma orbital, and the reason is at least at a minimum for this class we always define the internuclear axis as the z axis, so this is always the z axis, so it's always going to be the 2 p z's that are coming together head-on.
特别的,z总是形成sigma轨道,这是因为至少在这个课里面,我们总是定义核间轴为z轴,所以这总是z轴,所以2pz轨道总是,朝一个方向出现。
Suppose f of x, y, z equals k1, that is my equation, s1 and it gives me a solution s1.
假设我的方程是这样,然后给出了一个解。
It looks a little something like that, and the screen doesn't quite do it justice here, Z but there's two alphabets; A through Z, and then A through Z, -- but the inner A through Z is on a small -- it has a smaller diameter; so it's a ring of letters.
它看起就像那样的东西,那个画面做的不是这么公正,这里有两个字母表,A到Z,然后A到,但是戒指内部的A到Z是在一个小直径的上面-,它有一个小的直径,所以它是一个有字母的戒指。
So what we're going to see is less shielding, which means that it will actually feel a higher z effective.
那么我们将会看到更少的屏蔽,这意味着将会感受到更大的有效核电量。
They all have the same Z, the same proton number, but different A, which means number of neutrons varies.
有相同的Z,相同的质子数,但是不同的A,也就是中子数不同。
This now has, gee, a funny thing, x it says IF x is less than y AND x is less than z, then do something.
代码现在有,啊,一个有趣的东西,代码先是判断x是不是小于y并且,是不是小于z,然后做一些事情。
I then create a third variable called "z," add those two digits together, store the sum.
然后我声明了一个叫做“z“的变量“,把这两个数字加起来,把他们的总数存起来。
If we have a higher z effective, it's pulled in tighter, we have to put in more energy in order to eject an electron, so it turns out that that's why case 2 is actually the lowest energy that we need to put in.
而如果有效核电量更高,原子核的束缚也就更紧,我们不得不输入更多的能量来打出一个电子,这就是第二种情况,所需要输入的,能量更少的原因。
So our minimum that we're going to see is that the smallest we can have for a z effective 1 is going to be equal to 1.
所以我们能够看到的,最小的有效电荷量,等于。
And we know as we go across a row in the periodic table, what's happening is that z effective or the effective pull on the nucleus is increasing.
而我们知道沿着周期表的某一行向右看,有效核电量,或者说原子核的有效引力是在逐渐增大的。
9 or . 8 7 are possible, they actually aren't possible because even if we saw a total shielding, 1 the minimum z effective we would see is 1.
。39和0。87是可能的,实际上它们是不可能的因为即使,我们看到了一个完全的屏蔽,最小的有效电荷是。
And note that as Z increases, as the proton number increases the radius decreases for a given n number.
并注意到当Z不断增加,对于一个给定的n,即当质子数增加的时候,半径的n值就减小了。
So we should be able to calculate a z effective for any atom that we want to talk about, as long as we know what that ionization energy is.
我们应该可以计算出任何一个,我们想要谈论的原子的有效电荷量,只要我们知道电离能是多少。
The electron completely canceled out 1 it's equivalent of charge from the nucleus, such that we only saw in a z effective of 1.
电子完全抵消了来自原子核的等量电荷,这样我们仅仅看到有效的z为,在极端案例b中。
This is, in fact, a sigma 2 p z orbital is what this orbital is called.
这是这个轨道是因为,一个sigma2pz轨道。
Now, unlike high school math or in algebra Z where you call things X and Y and Z, in programming, in computer science, you're actually dealing with humans where it's useful to have a variable name that's more descriptive than X and Y and Z.
不像高中数学或者代数中,称为X和Y和,在程序设计和计算机科学里,你实际上是在和人打交道,在这里有个描述性比xyz更强的,变量名称是很重要的。
We know that it has to be equal to less than 2, because even if we had absolutely no shielding at 2 all, the highest z effective we could have is 2, so it makes perfect sense that we have a z effective that falls somewhere in the middle of those two.
我们知道它必须小于,因为即使完全没有一点屏蔽,最高的有效的z是,所以我们得到的有效电荷量处于,两者之间就非常讲得通了,让我们来看看另一个例子。
I'm binding a z to be some value, and then I'm going to run this.
我把z绑定到一个值上,然后运行下代码。
And if we experimentally know z what the ionization energy is, we actually have a way to find out what the z effective will be equal to.
我们实际上就有了一个办法,去找出有效的,等于多少,我们可以使用这里的方程。
But what you should be able to do is take a look at a list of answers for what we're saying z effective might be, and determining which ones are possible versus which ones are not possible.
但是你们应该能够做到的,是看一下这个可能的,有效电荷量的答案列表,并且确定哪些是可能的,哪些是不可能的。
Not only are we taking away an electron here, but we're also going to decrease shielding, so the electrons that are already in there are going to feel a higher z effective and will be pulling and the atom will be getting smaller.
这不只是因为我们拿走了一个电子,还因为我们这样做会减小屏蔽效应,这样留下的电子,将会感受到更大的有效核电量,也就会感受到更强的吸引力,使得原子变得更小。
The reason it's aluminum is because aluminum has a lower z effective, so it's not being pulled in as tightly by the nucleus, and if it's not being pulled in as tightly, you're going to have to put in less energy in order to ionize it, so that's why it's actually going to have the smaller ionization energy.
原因是,铝的有效核电量更少,所以没有被原子核束缚得更紧,而如果没有被束缚得更紧,你为了电离它所需要注入的能量也就更少,这就是,它的电离能会更低的原因。
In an extreme case b, we had a z effective of 2, so essentially what we had was no shielding at all.
我们有效的z是,所以本质上我们完全没有屏蔽。
It adds x to y and stores it into z. But if someone wants to be a even a little more snarky, what does this program do?
它把x加上y,再把结果存到z中,但是如果有人,想要做的有点不合常理点呢,那这个程序会做什么?
Already from this class if I told you that I gave you energies in some spectrum but they were off by a factor of four, what would you think? Maybe the Z is wrong.
从这节课开始,如果我告诉你我给了你,在某些光谱里的能量,但它们不属于四大元素之一,你会怎么想?也许Z是错的。
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