In this study, the formation of periodic ripples under a rigid wheel was investigated within the framework of finite element (FE) analysis. First, the capability of FEM to analyze periodic ripple formation was demonstrated under relatively low slippage. Then, a hypothesis for the generation ...
The atomic number of an element is equal to the total number of protons in the nucleus of the atoms of that element. The atomic number can provide insight into the electronic configuration of the element. For example, carbon has an electron configuration of [He] 2s22p2, since its atomic ...
The first to recognize these regularities was the German chemist Johann Wolfgang Döbereiner who, in 1829, noticed a number of triads of similar elements: Some triads Element Atomic massDensity chlorine 35.5 0.00156 g/cm3 bromine 79.9 0.00312 g/cm3 iodine 126.9 0.00495 g/cm3 calcium 40.1 1.55 ...
This number became known as an element’s atomic number. 后来,这个数字被称为元素的原子序数。 Today, elements on the periodic table are arranged by atomic number, which gives a more accurate understanding of element properties. 如今,元素周期表上的元素是按原子序数排列的,这使人们对元素的性质有了...
Alumna starts out the book by introducing the very necessary metal, aluminum, on her element page. Dr. Zinko rounds out the alphabet by presenting facts and other fun information about the metal, zinc, on his element page. Other members of the Metal Horn Tribe from Unimaise, plus some of...
Thevalenceof the elements (that is, the number of bonds formed with a standard element) is closelycorrelatedwith position in the periodic table, the elements in the main groups having maximum positive valence, or oxidation number, equal to the group number and maximum negative valence equal to ...
On 1 May 2014 a paper published inPhys. Rev. Lettby J. Khuyagbaatar and others states the superheavy element with atomic number Z = 117 (ununseptium) was produced as an evaporation residue in the48Ca and249Bk fusion reaction at the gas-filled recoil separator TASCA at GSI Darmstadt, ...
An element family is a set of elements sharing common properties. Elements are classified into families because the three main categories of elements (metals,nonmetals, and semimetals) are very broad. The characteristics of the elements in these families are determined primarily by the number of el...
T. et al. Synthesis of a new element with atomic number Z = 117. Phys. Rev. Lett. 104, 142502 (2010). Article ADS PubMed Google Scholar Khuyagbaatar, J. et al. 48Ca + 249Bk fusion reaction leading to element Z = 117: long-lived α-decaying 270Db and discovery ...
periodic table of elements 美 英 un.元素周期表;无素周期表 英汉 un. 1. 元素周期表 2. 无素周期表 例句