Definition:a rare barium,sodium aluminium silicate mineral 鈉鋇長石 nà bèi cháng shíFormula:BaNa2Al4Si4O16Origin:The name is derived from the chemical symbols of its composition....[繼續(xù)閱讀]

    Definition:A mineral occurring in small,green,transparent,monoclinic crystals. It is ahydrous phosphate of iron.板磷鐵礦bǎn lín tiě kuàngFormula:(Fe,Mg,Mn)3(PO4)2·4(H2O)Origin:named for Henry Ludlam(1824-1880),English mineralogist and collectorExample:Ludlami...[繼續(xù)閱讀]

    Definition:the occurrence or formation of twinned crystals 晶體孿生 jīng tǐ luán shēng,孿晶形成 luán jīng xíng chéngOrigin:late Old English twinn “double”,from twi-“two”;related to Old Norse tvinnr.Current verb senses date from late Middle EnglishExample:effect o...[繼續(xù)閱讀]

    Definition: the branch of chemistry or biochemistry concerned with measuring and studyingthe rates of reactions 動力學 dòng lì xuéOrigin:1864,from Greek kinetikos“moving,putting in motion,”from kinetos “moved,”v. kinein “to move”Example:study on nonisotherma...[繼續(xù)閱讀]

    Definition: (Mathematics) An (H,K) double coset in G,where G is a group and H and Kare subgroups of G,is an equivalence class for the equivalence relation defined on G by x～yif there are h in H and k in K with hxk=y. Then each double coset is of form HxK,...[繼續(xù)閱讀]

    Definition: a property of a gas,related to its partial pressure,that expresses its tendency toescape or expand,given by d=dμ/ RT,where μ is the chemical potential,R is the gasconstant,and T is the thermodynamic temperature逸度yì dùOrigin: 1625-1635; from La...[繼續(xù)閱讀]

    Definition:a symmetry element of some crystal lattices,in which the lattice is unaltered bya rotation about the axis combined with a translation parallel to the axis and equal to a fractionof the unit lattice distance in this direction螺旋軸luó xuán zhóuscre...[繼續(xù)閱讀]

    Definition:1.revolving or recurring in cycles; characterized by recurrence in cycles2.of pertaining to,or constituting a cycle or cycles3.chemistry of or pertaining to a compound that contains a closed chain or ring of atoms(contrasted with acyclic)環(huán)的huán...[繼續(xù)閱讀]

    Definition:(Chemistry) the ionic character of a solid電離度diàn lí dù,離子性O(shè)rigin: first known use: 1890Example:With approximate treatment by molecular orbital method,a new method for calculation ofionicity percentage of chemical bonds for inorganic compounds ...[繼續(xù)閱讀]

    Definition: the chemical element of atomic number 77,a hard,dense silvery-white metal自然銥zì rán yīIridium is a member of the transition series and is one of the densest metals. Iridium-platinumalloys are hard and corrosion-resistant and are used in jewelle...[繼續(xù)閱讀]