How Much You Need To Expect You'll Pay For A Good Crystal
How Much You Need To Expect You'll Pay For A Good Crystal
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27Local economists have looked into their crystal balls and found anything somewhat terrible.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》
Bismuth (Bi) appears to be a metal, but the quantity of electrons obtainable for electrical conduction is similar to that of semiconductors. Actually, bismuth is termed a semimetal. Molecular solids are often crystals fashioned from molecules or polymers. They are often insulating, semiconducting, or metallic, according to the kind of molecules during the crystal. New molecules are continuously remaining synthesized, and a lot of are made into crystals. The volume of different crystals is enormous.
A standard idea in crystal constructions would be the unit mobile. It is the smallest unit of quantity that permits similar cells being stacked jointly to fill all space. By repeating the sample on the device cell repeatedly in all Instructions, the whole crystal lattice may be made. A cube is The only example of a device cell. Two other illustrations are demonstrated in Figure 1. The very first will be the unit cell for your confront-centred cubic lattice, and the second is for any entire body-centred cubic lattice. These buildings are discussed in the next paragraphs.
Fig. three: A library of lattice symmetries is usually accessed by modifying the particle core and DNA shell.
Fig. 4: Constructing blocks with unique shapes and area chemistries immediate the development of distinctive crystal symmetries.
结晶�?When sea h2o is allowed to evaporate, salt crystals are deposited. 海水蒸发后，盐的结晶体就沉淀下来。
对任何宝石来说，颜色都是非常重要的，水晶也不例外。如果是水晶晶体是有颜色的，如粉水晶、黄水晶、紫水晶等，其颜色评价的最高标准则是明艳动人，不带有灰色、黑色、褐色等其他色调。如粉水晶，颜色以粉红为佳；紫水晶，要求颜色为鲜紫，纯净不发黑；黄水晶，要求颜色不含绿色、柠檬色调，以金橘色为佳。对于发晶来说，晶体的颜色也是很重要的。相同发丝的金发晶，晶体完全无色（白水晶）和晶体略偏茶色，肉眼的视觉观感也是有差别的，所以前者的价格会高于后者。
1A crystal chandelier lit the area.一盏水晶吊灯照亮了房间。《柯林斯英汉双解大词典》
仿制钛晶树水晶：钛晶是水晶里价格最昂贵的，造假者当然也不会放过这么好的产品。天然的环境下，在水晶里能生长个像树一样的钛晶，完全是可能的，只是这样的货很少，那我们的造假专家是如何做的呢，白水晶底下打个洞，激光打点成板状的钛晶进去，就这样这块水晶的身价就能飙升几十倍。往往有的钛晶戒面，会采用将钛晶部位割成板状，与圆面的水晶粘合的方法来制作。
⑤化学稳定�?非常好，在常温下仅溶解于氢氟酸，不溶解于其它各类酸、碱。在高温高压条件下可溶解于碳酸钠溶液中。
地质学家目前为止对晶洞形成还没有广泛认同的理论，但相信晶洞可以在任何埋藏的空腔内形成。这些空腔可以是火成岩中的气泡、树根下的空穴，甚至动物挖的地洞。经过漫长时间，空腔的外壁变硬，溶解的矽酸盐或方解石沉积到内壁。再经过漫长的时间，缓慢渗入的矿物使得晶体在空腔内部结晶。
正常的水晶在生长时，多可以发现和柱形尖端棱线平行的生长纹（progress lines）。由于在地底、岩洞中的生长空间多狭窄，尤其在遇到地震时，或地壳变动时，甚至容易遭到其他矿石的挤压，常常会压迫产生不同的「晶面」。还有，当水晶还是在液态状的时候，常常也会包覆着其他的矿石、泥灰一起结晶成长，如金红石（稍后变成发晶）、火山泥灰（稍后变成幻影水晶）等等。所有的这些，都是「自然的一部分」，请不要视为「瑕疵」。
crystal, any good materials in which the ingredient atoms are organized in a very definite sample and whose floor regularity displays its interior symmetry.
Binary crystals are present in quite a few structures. Some pairs of things more info variety multiple structure. At room temperature, cadmium sulfide may crystallize possibly during the zinc blende or wurtzite composition. Alumina also has two attainable constructions at home temperature, α-alumina (corundum) and β-alumina. Other binary crystals show distinct buildings at diverse temperatures. Among the many most intricate crystals are People of silicon dioxide (SiO2), which has 7 various constructions at various temperatures and pressures; the commonest of such structures is quartz.