原子序数

Compared with iodine, Gold has a larger atomic number and X-ray absorption coefficient.

金与碘相比，有着更高的原子序数和X射线吸收系数。

The results show that the decomposition of alkaline earth metal nitrates become more difficult as the atomic number increases.

结果表明，碱土金属硝酸盐分解成为氧化物的难度随着原子序数的增大而增加。 Mg(NO3)2在550 ℃时就可以直接分解为MgO。

According to those experiments, it was found that the slope was decreased when the atomic number of the cation was increased for alkali metal chloride solutions and alkaline-earth metal chloride solutions.

分析这些实验数据后，发现直线的斜率随着碱金属和碱土金属氯化物盐溶液阳离子原子序数的增加而下降。

Atomic number Z = 25, atomic weight of 54938, the chemical symbol Mn, only the F there is a stable isotope, radioactive short-lived, there are three kinds of allotrope α,β,γ.

原子序数Z＝25，原子量54938，化学符号为Mn，只F有一种稳定同位素，放射性的寿命很短，有三种同素异形体α、β、γ。

Products Introduction: Silicon cycle, the department of the first type IV elements, is a non-metallic element, atomic number 14, atomic weight 28.80; density of 2.33g/m3; melting point of 1410 ℃; boiling point of 2355 ℃; resistively for 2140Ω.M; includes two types of stereotypes and crystal allotrope.

硅周期系第 IV 类元素，是非金属元素，原子序数14，原子量为28.80；密度为2.33g /m3；熔点为1410℃；沸点为2355℃；电阻率为2140Ω。m ；有无定型和晶体两种同素异形体。

Alpha decay commonly occurs in elements with atomic numbers greater than 83, but can occur in some rare-earth elements in the atomic-number range of 60 to 71.

发射α粒子的主要是重于铋(lutetium，原子序数83)和从钕(neodymium，原子序数60)到镏(Iutetium，原子序数71)的稀土元素，α衰变的半衰期，从1微秒(10-6秒)到约1017秒。

Alpha particle s have two positive charges and a mass of four atomic mass units; they are identical to helium nuclei.

因为α粒子有两个正电荷，质量为4，射出后产生的子核的正核电荷和原子序数都比母核小两单位，质量小四单位。

Any of a group of five chemically related nonmetallic elements including fluorine,chlorine,bromine,iodine,and astatine.

锕类任何化学性质相似，原子序数在89与103之间变化的放射性元素

For the request of the high resolution ability of X-ray imaging, the inorganic scintillating materials with high effective atomic numbers and high density are studied intensely.

针对X射线高分辨成像的要求，具有较高有效原子序数和较大密度的无机闪烁材料成为当今研究的热点，重点阐述了溶胶－凝胶法制备这类闪烁薄膜的研究现状，并对其今后的发展进行了展望。

Lanthanides belong to the sixth cycle of the periodic table Ⅲ B family, are all solid metal, they are La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, holmium, erbium, thulium, ytterbium, and lutetium were 15 kinds of metals and their periphery are two layers of electronic 5d16s2, while the peripheral third layer f orbital but never zero to 14, so the external electronic structure of 4f0-145d16s2, and therefore these elements in oxidation number are to 3, very close chemical properties, extraction, when it is difficult to separate them they are mostly multi-element mineral mix, more difficult to increase refining, and their atomic number of 57-71, one by one to increase the number of protons the nucleus, and thus extranuclear electron of gravity is also growing, so that atomic radius decreases with increasing atomic number Z, which makes lanthanides contraction, ionic radius is also reduced, which also makes Zr, Hf, Nb and Ta, Mo and W, the atom and ionic radius very close to each other they also determine a similar nature, resulting in difficult separation, also the tribe Ⅷ of the fifth cycle, ruthenium, rhodium, palladium, and the sixth cycle, osmium, iridium, platinum is very similar in nature, thus The six elements, said platinum group elements.

镧系元素属于周期表第六周期中ⅢB族，全部是固体金属，它们是镧、铈、镨、钕、钷、钐、铕、钆、铽、镝、钬、铒、铥、镱和镥共十五种金属元素，它们的外围两层的电子均是5d16s2，而外围第三层的f轨道电子却从零增加到14个，所以外围电子结构为4f0－145d16s2，而使这些元素氧化数均为＋3，化学性质极为接近，提炼时很难分开，它们的矿石又大多是多种元素混在一起的，更增加提纯难度，它们的原子序数为57－71，核内质子数逐个增加，因而对核外电子引力也不断增强，使原子半径随原子序数Z增加而减小，这就使镧系元素收缩、离子半径也缩小，这也使得Zr和Hf，Nb和Ta、Mo和W等原子和离子半径都很接近、也决定了它们彼此性质类似，以致难以分离、也使第Ⅷ族中第五周期的钌、铑、钯和第六周期的锇、铱、铂在性质上极为相似，因而称这六个元素为铂系元素。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。