为了解碱式硫酸镁晶体结构和晶体生长过程,构建碱式硫酸镁超级晶胞模型,采用Materials Studio 7.0软件中的Morphology程序对碱式硫酸镁2×2×2超级晶胞及其(201)、(202)、(203)、(111)和(114)真空slab计算模型进行平衡态计算,...为了解碱式硫酸镁晶体结构和晶体生长过程,构建碱式硫酸镁超级晶胞模型,采用Materials Studio 7.0软件中的Morphology程序对碱式硫酸镁2×2×2超级晶胞及其(201)、(202)、(203)、(111)和(114)真空slab计算模型进行平衡态计算,计算了其主要显露面族的Distance值和晶面面积百分比等相关参数。计算结果表明,碱式硫酸镁生长符合螺旋位错生长机制,其形貌会呈现晶须状但其中会掺杂着六棱柱等不规则的结构与实验结果吻合。展开更多
In response to various environmental factors in offshore South China Sea,a group of microstructures of the screw dislocation are assembled in multiphase screw dislocations on the surface of the nacreous layer of Pteri...In response to various environmental factors in offshore South China Sea,a group of microstructures of the screw dislocation are assembled in multiphase screw dislocations on the surface of the nacreous layer of Pteria penguin from the coastal waters of Hainan Island,China.The results of the transmission and scanning electronic microscope testing show that organic matter periodically secreted by epithelial histology of mantle of Pteria penguin pre-forms the original screw dislocation growth tem-plate in the form of film,along with its function to select,identify,and adhere to the amorphous calcium carbonate particles as the fine organic venations diffused in the epitaxial screw growth area.With the inducement and screw modulation of the or-ganic film and venations,the amorphous calcium carbonate particles gradually evolve into the pseudohexagonal self.aragonite microsheet with long-range order and screw dislocation structure by location-selecting tropism and screw dislocation growth.Numerous micron-scale aragonite microsheets join in the cluster's interactive movement and screw dislocation self-assembly of the organic film,stacking forward along the axis C spirally and forming the nacreous layer with screw dislocation structure.展开更多
We systematically investigated the electrical nanoplates through field effect transistor and properties of spiral-type and smooth Bi2Se3 conductive atomic force microscopy （CAFM） measurement. It is observed that bot...We systematically investigated the electrical nanoplates through field effect transistor and properties of spiral-type and smooth Bi2Se3 conductive atomic force microscopy （CAFM） measurement. It is observed that both nanoplates possess high conductivity and show metallic-like behavior. Compared to the smooth nanoplate, the spiral-type one exhibits the higher carrier concentration and lower mobility. CAFM characterization reveals that the conductance at the screw-dislocation edge is even higher than that on the terrace, implying that the dislocation can supply excess carriers to compensate the low mobility and achieve high conductivity. The unique structure and electrical properties make the spiral-type Bi2 Se3 nanoplates a good candidate for catalysts and gas sensors.展开更多
文摘为了解碱式硫酸镁晶体结构和晶体生长过程,构建碱式硫酸镁超级晶胞模型,采用Materials Studio 7.0软件中的Morphology程序对碱式硫酸镁2×2×2超级晶胞及其(201)、(202)、(203)、(111)和(114)真空slab计算模型进行平衡态计算,计算了其主要显露面族的Distance值和晶面面积百分比等相关参数。计算结果表明,碱式硫酸镁生长符合螺旋位错生长机制,其形貌会呈现晶须状但其中会掺杂着六棱柱等不规则的结构与实验结果吻合。
基金supported by National Basic Research Program of China (Grant No. 49772096)National Basic Research Program of Hubei,China (Grant No. 2005ABA005)
文摘In response to various environmental factors in offshore South China Sea,a group of microstructures of the screw dislocation are assembled in multiphase screw dislocations on the surface of the nacreous layer of Pteria penguin from the coastal waters of Hainan Island,China.The results of the transmission and scanning electronic microscope testing show that organic matter periodically secreted by epithelial histology of mantle of Pteria penguin pre-forms the original screw dislocation growth tem-plate in the form of film,along with its function to select,identify,and adhere to the amorphous calcium carbonate particles as the fine organic venations diffused in the epitaxial screw growth area.With the inducement and screw modulation of the or-ganic film and venations,the amorphous calcium carbonate particles gradually evolve into the pseudohexagonal self.aragonite microsheet with long-range order and screw dislocation structure by location-selecting tropism and screw dislocation growth.Numerous micron-scale aragonite microsheets join in the cluster's interactive movement and screw dislocation self-assembly of the organic film,stacking forward along the axis C spirally and forming the nacreous layer with screw dislocation structure.
文摘We systematically investigated the electrical nanoplates through field effect transistor and properties of spiral-type and smooth Bi2Se3 conductive atomic force microscopy （CAFM） measurement. It is observed that both nanoplates possess high conductivity and show metallic-like behavior. Compared to the smooth nanoplate, the spiral-type one exhibits the higher carrier concentration and lower mobility. CAFM characterization reveals that the conductance at the screw-dislocation edge is even higher than that on the terrace, implying that the dislocation can supply excess carriers to compensate the low mobility and achieve high conductivity. The unique structure and electrical properties make the spiral-type Bi2 Se3 nanoplates a good candidate for catalysts and gas sensors.
