纳米

In the single crystal of C60 with a FCC structure,positron mainly appears outside the C60 molecule.The main annihilation space is the interspace between molecules.The calculated positron bulk lifetime in C60 is 352ps, which agrees with experiment value of 356ps in literature.In carbon nanotube bundles with different dimeters,as the diameter of carbon nanotubes increases,the main space where positron appears changes from the interspace of carbon tubes to the space inside carbon tubes,the radio between positron annihilation with valence eletrons and core eletrons becomes larger,the positron bulk lifetime in carbon nanotube increase rapidly first and come to be a constant at the end.The calculated positron lifetime of carbon nanotube with a dimeter of 0.8～1.6ns is 332～470ps,which agrees with the experiment value of 394ps.Positron annihilation has been studied in widly used compound semiconductors.

计算结果表明：在片层结构的石墨晶体中，正电子主要在石墨层间的空隙中湮没，计算出的石墨中的正电子寿命为208 pS，与文献中的实验结果215 ps符合很好；在金刚石单晶中，正电子主要在碳原子之间的空隙中存在并发生湮没，计算出的金刚石中的正电子寿命为115 ps，文献中的实验结果110 ps左右符合；在面心立方结构的C60晶体中，正电子主要在C60分子球壳内外侧及分子之间存在，C60球形分子中心正电子分布很少，正电子的湮没区域集中在C60分子之间的空隙区域，计算出的C60中的正电子寿命为352 ps与文献中的实验结果356ps相符合；对于不同管径碳米管束中的正电子分布，随着碳纳米管直径的增加，碳纳米管束中的正电子由主要在碳纳米管管间的区域出现转变为主要在碳纳米管管内中心的区域出现：碳纳米管束中的正电子与碳原子的价电子的湮没概率变得越来越大，与核心电子的湮没概率变得越来越小；碳纳米管束中正电子的湮没寿命先迅速增大，而后趋于一定值。

Nanometer pearl powder creates the fourth times of pearl cosmetic----nanometer times. We select carefully limnetic pearl with high quality, adopt advanced super-sonic airstream physical manufacturing technic. Through super-sophisticated machine, we produce nanometer pearl powder with average diameterof 40-100 nanometer ( 1 millimeter = 1000000000 nanometer), equivalent to one hundredth of human body's pore, that is to say, by nanometer technic, we can powder one bead of pearl with 8 millimeter diameter into 64 trillion pieces, which means, everyone on the earth can have more than 10 thousand pieces.

纳米珍珠粉开创珍珠美容第四时代—纳米时代，我们精选优质淡水珍珠，采用先进的超音速气流物理粉碎技术，通过超精密设备生产出的平均粒径在40-100纳米（ 1 毫米＝ 1000000000纳米）左右的纳米级珍珠粉，细度只有人体毛孔的1/100，也就是是说将一颗直径8毫米的珍珠通过纳米技术粉碎等分，可粉碎为64万亿粒，相当于每个地球人都可以拿到1万多粒。

Also, we can find that the diameter of carbon nanotubes affects the structure of Na nanowire obviously. In the carbon nanotube (4,4), the Na nanowire is monatomic linear strcture, while it is of helicity and larger diameter.

且碳纳米管的直径对纳米线的直径及结构有明显的影响，碳纳米管(4，4)中得到的纳米线为单原子排列的直线结构，而碳纳米管(6，6)中得到的纳米线则为直径较大的、带有一定螺旋性的线性结构。

The iron nanoparticles in inner core have good magnetism and targeting heating effect. The temperature can go up to 52 ℃ in the case that 0.1 g carrier (carbon-coated iron nanoparticles) is injected in a local point of pig's liver,while the temperature can go up to 42℃ in the case that pig's liver uniformly containing carrier of 0.4 wt.% and 45℃ in the case that pig's liver uniformly containing carrier of 0.6 wt.%. Carbon-coated iron nanoparticles also has good antioxidation and stability by an X-rays diffraction structural analysis.

铁纳米粒子磁场强，靶向效果好，有较佳的磁靶向发热效应，在动物病灶局部放置0.1 g碳包铁纳米粒子将能使发热温度平均升到52℃；而将碳包铁纳米粒子均匀与猪肝混合也有明显的产热效果：含量0.4%碳包铁纳米粒子的一组猪肝能将温度升到42℃，而含量0.6%碳包铁纳米粒子的一组猪肝能将温度升到48℃。X射线衍射表明借助于碳的包裹，碳包铁纳米粒子有好的抗氧化性和稳定性。

This new material and its science and technology have involved with nearly all the existing scientific and technical fields,which has been paid attention to by the scientific circle all over the world.

自1984年德国科学家Gleiter提出了纳米晶材料的概念并首次获得人工制备的纳米晶体后，1987年美国的Siegel博士又研制成功纳米TiO2材料以来，世界各国材料科学家竞相开展对这种新材料的研究工作。1992年11月在墨西哥的坎昆召开了第一届国际纳米结构材料会议，同年出版了有关纳米材料的新杂志，这标志着有关纳米材料和纳米技术的研究进入了一个崭新的阶段。

By the testing means of electron-spectroscopy for chemical analysis , thermogravimetric analysis , differential scanning calorimetry , transmission electronmicroscopy , the results have shown that the emulsion polymerization in situ in the presence of nano-particle of calcium carbonate can happen smoothly and successfully and the surface of nano-particle of calcium carbonate have been capsulated by polymer of acrylates, which prevent from the agglomerating of nano-particles of calcium carbonate. Because the copolymer of acrylate has good compatibility with some plastics such as PVC, ABS, AS and so on, so the dispersion of nano-scale calcium carbonate as nanometer size in these plastics can be reached more easily and the effects of nanometer can happen.

通过X射线光电子能谱、热失重分析、动态扫描量热分析、透射电子显微镜等手段，证实在纳米碳酸钙原生粒子存在下，可以进行丙烯酸酯类的原位乳液聚合，乳液聚合顺利，纳米碳酸钙表面被丙烯酸酯类聚合物所包覆，使纳米碳酸钙粒子间的团聚不易发生，同时由于丙烯酸酯类聚合物与PVC、ABS、AS等极性聚合物具有较好的相容性，从而使纳米碳酸钙在聚合物基体中能达到纳米状态分散，从而发挥纳米效应。

By varying the kind and relative amount of the reacting agent, Se submicrotubes, Se nanorods, Se shuttles, urchin-like assembly of Se nanorods, Te nanowires, Te nanobelts, Te nanotubes, thornlike 1D assembly of Te nanothreads can be fabricated on a large scale. Both light and thermal effects play significant roles in this visible-light-assisted technique.

通过调节反应物的种类和配比，可以大规模地合成诸如硒亚微米管、硒纳米棒、硒梭标、(来源：ABd5C论文网www.abclunwen.com)硒纳米棒形成的海胆状结构、碲纳米线、碲纳米带、碲纳米管和棘状Te纳米丝等一维纳米组装结构。

They exhibit bending deformation following the direction of the nanotube curvature. At room temperature, a nanoparticle smaller than Au 70 often escapes from the carbon nanotube surface and can be captured again by the nanotube or coalesces with other nanoparticles to form a larger nanoparticle.

纳米颗粒在碳纳米管上形成以后，小于Au 70的纳米颗粒有可能脱离碳纳米管运动，它们在脱离后可能再度被碳纳米管俘获或者跟其他纳米颗粒结合并被重新吸附到碳纳米管上来。

By the combination of experimental results with theory of crystal growth, some growth models and growth mechanisms were proposed. Research results confirmed that pillar-shaped TaC whisker with spherical droplet at the end grew via a vapor-liquid-solid mechanism, pillar-shaped whisker with pyramid-like end was formed via a vapor-solid mechanism, awl-shaped TaC whisker with zigzag end formed via a liquid-solid mechanism, awl-shaped TaC whisker with growth step at the end has a growth mechanism of screw dislocation mechanism. The growth mechanism of dumbbell-shaped MgO nanowhisker and NaCl particle-decorated MgO nanowhisker is VS; C and MgO powder-yielded MgO nanowhisker was formed via a VLS mechanism, Mg powder-yielded MgO microwhisker and MgO microsized or nanosized crystal sheet grew via a VS mechanism. In the Si and SiO〓 nanostructures, Si nanowires formed in higher-temperature zone grew via oxide-assistant mechanism, while Si nanowires or nanorods formed in lower-temperature zone have a growth mechanism of VLS, and the growth mechanism of SiO〓 nanowires is VS.

研究确定呈平直柱状且头部带有球形颗粒的TaC晶须是通过气-液-固机制生长；头部呈之字型的锥状TaC晶须则通过液-固机制生长；晶须头部为四棱锥状的粗长TaC晶须的生长机制是VS机制；顶端呈锥状且有生长台阶的TaC晶须通过螺位错机制生长；哑铃状氧化镁晶须和氯化钠颗粒修饰的氧化镁纳米晶须的生长机制是气-固机制：当采用C+MgO粉提Mg源时形成的氧化镁纳米晶须的生长机制是VLS，而采用直接热蒸发Mg粉时得到的氧化镁微米晶须的生长机制为VS，纳米和微米晶片的生长机制均为VS机制；在高温区，硅纳米线的生长机制是助氧化机制，在低温区硅纳米线和纳米棒的生长机制是VLS机制，而氧化硅纳米线的生长中VS机制占主导地位。

Results revealed that tetraleg-nanorods are multi-crystalline, double-edged nanocombs with twins are bicrystalline, other structures, such as nanorods, namowires, nanobelts, nanoarays , nanomails, single-edged combs and nanosaws, are single wurtzite crystalline.

研究表明四针状纳米棒为多晶结构，孪晶双面纳米梳为双晶结构，纳米棒、纳米线、纳米带、纳米阵列、纳米钉以及多种单面齿状纳米结构均为单晶纤锌矿晶体结构。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。