Definition: Minerals have been collected at Baveno for centuries. The locality,which gaveits name to the minerals bavenite and to the Baveno law for orthoclase twins,has producedsome of the world’s finest orthoclase crystals.巴韋諾雙晶bā wéi nuò shuāng jīng...[繼續(xù)閱讀]

    Definition: An uncommon twin law applicable in feldspar,in which the twin plane andcomposition surface are. A Baveno twin usually consists of two individuals.巴韋諾雙晶定律bāwéi nuò shuāng jīng dìng lǜ...[繼續(xù)閱讀]

    Definition: The Becke Line Test is a technique in optical mineralogy that helps determine therelative refractive index of two materials. It is done by lowering the stage (increasing the focaldistance) of the petrographic microscope and observing which dir...[繼續(xù)閱讀]

    Definition: The Berek compensator is an optical device that is capable of quantitativelydetermining the wavelength retardation of a crystal,fiber,mineral,plastic film or otherbirefringent material.貝累克補(bǔ)償器bèi lèi kè bǔ cháng qì...[繼續(xù)閱讀]

    Definition: a chart used to determine the coordinates in reciprocal space of X-ray reflectionsthat produce貝爾納圖bèi ěr nà túOrigin: named after John Desmond Bernal,who created the diagram for interpreting X-rayphotographs...[繼續(xù)閱讀]

    Definition: a crystal of low symmetry in which the index ellipsoid has three unequal axes二軸晶èr zhóu jīngExample:Based on geometric construction and theoretical derivation,the directions of the two kinds ofoptical axes in the biaxial crystal have been dedu...[繼續(xù)閱讀]

    Definition: The couple of reflections h, k, l and ,, is called a Friedel pair, or Bijvoetpair. Their intensities are equal if there is no absorption,but differ otherwise. Friedel’s law thendoes not hold. Generally speaking,when absorption is prese...[繼續(xù)閱讀]

    Definition: In mathematics,a binary operation is a calculation involving two operands,inother words,an operation whose arity is two. Examples include the familiar arithmeticoperations of addition,subtraction,multiplication and division. More precisely,a b...[繼續(xù)閱讀]

    Definition: a prism having a highly obtuse angle to facilitate beam splitting雙棱鏡shuāngléng jìngExample:The distribution curves of light intensity of orthogonal biprism interference is made fromexperimental results.通過實(shí)驗(yàn)結(jié)果作出正交雙棱鏡干涉的光強(qiáng)度分布曲線。Extend...[繼續(xù)閱讀]

    Definition: An n-gonal bipyramid or dipyramid is a polyhedron formed by joining an ngonal pyramid and its mirror image base-to-base. The referenced n-gon in the name of thebipyramids is not an external face but an internal one,existing on the primary symm...[繼續(xù)閱讀]