PCR是一座反应堆的核中子数会在反应堆能量增加后增加或减少的衡量标志。
The power coefficient of reactivity (PCR) is a measure of whether a particular reactor's nuclear neutron population will tend to increase or decrease after an increase in the reactor's power.
在一个原子的核内，中子和质子聚合在一起。
Neutrons and protons are bound together in the nucleus of an atom.
重水之所以重是因为水中氢的重量是普通氢的两倍（它的原子核中有一个质子和一个中子，而不仅仅是一个质子）。
Heavy water is heavy because the hydrogen in it weighs twice as much as ordinary hydrogen (it has a proton and a neutron in its nucleus, instead of just a proton).
同时还需要足够多的、可裂变的原子核用于中子进行撞击，换句话说，需要一个临界质量。
There also need to be enough fissionable atoms about for the neutrons to bumpinto—in other words, a critical mass.
在经历超新星后，假如剩下的残核小于三个太阳质量，爆炸的残余物质就将可能演变成旋转着的中子团。
Immediately after supernova, if the remnant core has a mass of less than three SUNS, one would expect a blob of degenerate neutron matter to be spinning in the explosion's wake.
氢融合技术可能需要超过20年才能被用于是用，无中子核融合技术提供了一种替代的方式。
While practical hydrogen fusion may be twenty years away, aneutronic fusion offers an alternative.
硼是一种可以吸收中子的元素，中子是一种存在于所有的原子核中的亚原子粒子。
Boron is an element with the ability to absorb neutrons, the sub-atomic particles that occur in the nucleus of all atoms.
产生的新组成包括两个新原子核(副产物)、一些光子(伽马射线)以及更多的自由中子，它们是参与核裂变反应并产生能量的关键。
Those new pieces include two new nuclei (byproducts), some photons (gamma rays), but also some more free neutrons, which is the key that makes nuclear fission a good candidate to generate energy.
重水因含重氢而得名。重氢是氢原子的一种，其原子核中含有一枚中子，加之正常氢元素中的质子，重量为一般氢原子的两倍。
Heavy water gets its name because it contains deuterium, a form of hydrogen that has a neutron in its nucleus as well as the usual proton and thus weighs twice as much as the ordinary sort.
当电子流通过灯泡中带正电荷的气体(质子和中子核)。
When electric currents (electrons) are passed through positively-charged gasses (protons and neutron nucleuses) inside bulbs.
在它们的原子核中质子数是相同的(这是一个元素定义性的特征)，但是中子的数量不同。
They have the same number of protons in their nuclei (this is the defining characteristic of an element), but different Numbers of neutrons.
重氢是原子核中多一个中子的氢。
A deuterium atom is a hydrogen with an extra neutron in its nucleus.
此时温度降到10亿摄氏度，质子和中子开始形成原子核-带电原子的内核。
At a temperature of one billion degrees Celsius, protons and neutrons start to come together to form nuclei, the charged cores of atoms.
所有原子在其核内都含有一个或一个以上的中子。
强核力的一部分也由中子提供，在大多数原子核内，中子比质子数量多，并且不带电荷。
Some of this force is also supplied by neutrons, which outnumber protons in most nuclei and have no electric charge.
通过分析和计算锕系核裂变截面和全套中子反应截面获取了一组锕系核的裂变位垒参数。
The fission barrier parameters for actinide nuclei were obtained by analysis and calculations of fission cross-sections and complete neutron reaction cross sections.
同位素：一种化学元素的两个或多个类型，它们的原子核具有相同的质子数，而中子数却不同。
Isotope: One of two or more species of atoms of a chemical element having nuclei with the same number of protons but different Numbers of neutrons.
在原子核内，中子和质子堆叠在一起，同样也根据量子力学互相交换能量。
Within an atom's nucleus, neutrons and protons jostle and change energy according to quantum mechanics, too.
难以捉摸的量子力学表明，中子“太多”和“太少”有时会重叠出现，因而一些特定的元素没有稳定的同位素(或称变体，核内中子数不同)。
And the vagaries of quantum physics mean that "too many" and "too few" sometimes overlap, and there is thus no stable isotope (or variant, with fewer or more neutrons) of a particular element.
中子与原子核或与电子并没有可察觉的电磁相互作用。
A neutron has no appreciable electromagnetic interaction with nuclei or with electrons.
氘核：氘原子的原子核，由一个质子和一个中子组成，被视为带单位正电荷的亚原子。
Deuteron: the nucleus of a deuterium atom consisting of a proton and a neutron regarded as a subatomic particle with unit positive charge.
科学家们知道：只有在中子撞击原子的原子核时，中子才可能处于游离状态。这种碰撞会改变原子核的运动轨迹。
Scientists know that a neutron is loose only when the neutron hits the nucleus of an atom. The collision changes the path of the nucleus.
虽然这颗星星的内部是大部分中子构成的流体，地壳是由破裂的原子，未知元素的原子核构成。
Though the interior of the star is a kind of fluid mass of mostly neutrons, the crust is composed of broken-up atoms, the nuclei of unknown elements.
查德威克认为这是由于铍原子核释放了不带电的粒子——他所称的中子所致。
Sir james chadwick's explanation was that the beryllium nuclei had released their non-electrical particles which he called neutrons.
中子和质子构成了原子核。
中子符合计数在核材料认证和管理中有着广泛的应用。
Neutron coincidence counting is widely used in the authentication and management of nuclear material.
中子测量技术是核保障领域非破坏性分析技术中重要方法之一。
Neutron measurement technology is one of important Non-destructive assay methods in nuclear safeguards field.
中子测量技术是核保障领域非破坏性分析技术中重要方法之一。
Neutron measurement technology is one of important Non-destructive assay methods in nuclear safeguards field.
应用推荐