Crystal Fundamentals Explained
Crystal Fundamentals Explained
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27Local economists have appeared into their crystal balls and viewed a little something somewhat unpleasant.当地的经济学者们已预测到将会出现棘手的问题。《柯林斯英汉双解大词典》
the sound point out of numerous straightforward substances, that have an everyday condition and surfaces organized in similar designs
发晶的价值取决于发的颜色、罕见性及大小，一般是发色鲜艳、块度大的价格高。水胆水晶的价值主要取决于水胆及晶体的大小、透明度的高低。如果水胆较大并有一定形态，便可加工成较为珍贵的工艺品。另外水胆中的水也有一定的科学研究价值，通过它们可了解几百万年前地球上水的成分及变化。
Tetragonal: These crystals type prisms and double pyramids. The structure is sort of a cubic crystal, besides just one axis is for a longer time than another.
Fig. 4: Building blocks with different styles and floor chemistries immediate the formation of distinctive crystal symmetries.
⑧、雕刻：立体感强，工艺高，做工精细，成本高。分手工雕刻图形、机器雕刻文字。
光泽：玻璃光泽。断口处为油脂光泽。光泽，指宝石表面对光线反射的一种光学性质。观察水晶的光泽，可用手握着它，以灯光或窗户投进来的光线看表面反射，透明水晶亮度与光泽强弱有关。
The elements are uncovered in a number of crystal packing preparations. The commonest lattice structures for metals are These received by stacking the atomic spheres into probably the most compact arrangement.
13Nearly all personal computers have a quartz-crystal clock to control their Procedure.几乎所有的计算机都有一个石英晶体时钟来调节它们的运行。
Crystals with noticeable flat faces are referred to as euhedral crystals, even though People lacking described faces are named anhedral crystals. Crystals consisting of purchased arrays of atoms that are not generally periodic are referred to as quasicrystals.
There are two this kind of attainable periodic preparations. In Each and every, the first layer has the atoms packed into a airplane-triangular lattice in which each atom has 6 speedy neighbours. Figure two reveals this arrangement with the atoms labeled A
The sodium chloride crystal lattice is characterised because of the close packing from the optimistic sodium ions and adverse chloride ions. Just about every sodium ion is surrounded by six chloride ions, and each chloride ion is surrounded by six sodium ions, read more developing a remarkably steady and symmetrical construction.
Crystals are labeled generally speaking categories, like insulators, metals, semiconductors, and molecular solids. Just one crystal of the insulator is frequently transparent and resembles a piece of glass. Metals are shiny unless they have got rusted. Semiconductors are sometimes shiny and sometimes clear but are never rusty. Many crystals can be categorized as only one sort of solid, while some have intermediate behaviour. Cadmium sulfide (CdS) might be geared up in pure form and is an excellent insulator; when impurities are added to cadmium sulfide, it turns into an interesting semiconductor.
This crystal composition is responsible for the one of a kind Actual physical and chemical properties of sodium chloride, including its large melting point, electrical conductivity, and talent to type ionic bonds simply.