Probing terahertz surface plasmon waves in graphene structures

Epitaxial graphene mesas and ribbons are investigated using terahertz (THz) nearfield microscopy to probe surface plasmon excitation and THz transmission properties on the sub-wavelength scale. The THz near-field images show variation of graphene properties on a scale smaller than the wavelength, and excitation of THz surface waves occurring at graphene edges, similar to that observed at metallic edges. The Fresnel reflection at the substrate SiC/air interface is also found to be altered by the presence of graphene ribbon arrays, leading to either reduced or enhanced transmission of the THz wave depending on the wave polarization and the ribbon width.Comment: accepted for publication in Applied Physics Lette

Hexaaqua­magnesium(II) bis­{[N-(4-meth­oxy-2-oxidobenzyl­idene)glycyl­glycinato(3−)]cuprate(II)} hexa­hydrate

In the title complex, [Mg(H2O)6][Cu(C12H11N2O5)]2·6H2O, the CuII atoms lie at the center of the square plane of triple negatively charged O,N,N′,O′-tetra­dentate Schiff base ligands, which are coordinated by one phenolate O atom, one imine N atom, one deprotonated amide N atom and one carboxyl­ate O atom. The MgII center, which sits on an inversion center, is coordinated by six aqua ligands and exhibits a slightly distorted octa­hedral conformation. The asymmetric unit consists of an [N-(4-meth­oxy-2-oxidobenzyl­idene)glycyl­glycinato]cuprate(II) anion, one half of an [Mg(H2O)6]2+ cation and three free water mol­ecules. The cations and anions form columns by O—H⋯O hydrogen bonds

Research on Multifunctional Integrated Internet Platforms

Throughout the development of China’s Internet industry for more than 20 years, we can tease out three stages that can represent the trend of the times: the first stage can be called the Portal Era with the entire Internet industry dominated by portal websites. However, with several major portals ’transitions after being unable to maintain effective operation of their profit model, the Portal Era came to an end. The second stage we call Social Network Era , represented by Sina Mircroblog and WeChat. The former had successful transitions after several ups and downs and the latter is trending and promising. Also vigorously developing are various social websites and mobile apps. In the midst of the laughter of those entrepreneurs, the industry came to a third stage of development: The Era of E-business. These three stages did not appear one after another in chronological order. Social networks and e-business platforms in fact exist simultaneously with two groups of people hitting on different roads that lead to the same destination. Social networks and business platforms are now already inescapably intertwined with each other: social networks attract traffic for e-business platforms while e-business platforms provide profit in return. What is more, big Internet giants aim to create a theme park magnificently situated in the internet world to provide one-stop services like portal browsing, e-business, third party payment, social networking and entertainment. At the same time, social network leaders also gradually provided e-commerce .and the third party payment service without willing to pave way for others. Longer ago, with the smart phones sweeping the world, the mobile internet era approached quietly while online and offline businesses increasingly converged. Therefore, we have reasons to believe that the next important stage of Internet development will be named as the era of multi-functional integrated Internet platforms

Triaqua­bis{μ-N-[N-(4-meth­oxy-2-oxidobenzyl­idene)glyc­yl]glycinato(3−)}cadmium(II)dicopper(II) dihydrate

In the title compound, [CdCu2(C12H11N2O5)2(H2O)3]·2H2O, the CuII atoms are in a square plane of N2O2 atoms contributed by the tetra­dentate Schiff base trianion. The CuII atoms are coordinated by one phenolate O atom, one imine N atom, one amido N atom and one carboxyl­ate O atom. The CdII atom is connected via the carboxyl­ate groups, forming a heterotrinuclear CuII–CdII–CuII system. The CdII atom is seven-coordinate in a penta­gonal-bipyramidal geometry with four O atoms from two carboxyl­ate groups and three aqua ligands. The heterotrinuclear mol­ecules are linked to the uncoordinated water mol­ecules by O—H⋯O hydrogen bonds into a three-dimensional framework

Hexaaqua­cobalt(II) bis­{[N-(4-meth­oxy-2-oxidobenzyl­idene)glycylglycinato]nickel(II)} hexa­hydrate

In the title compound, [Co(H2O)6][Ni(C12H11N2O5)]2·6H2O, the NiII atom has a nearly square-planar coordination with two N and two O atoms of the N-(4-meth­oxy-2-oxidobenzyl­idene)glycylglycinate Schiff base ligand (L 3−). The CoII atom sits on an inversion center and is coordinated to six aqua ligands in a slightly distorted octa­hedral geometry. The [Co(H2O)6]2+ cations and [NiL]− anions form columns along the a axis by O—H⋯O hydrogen bonds. Additional hydrogen bonds between the uncoordinated and coordinated water molecules help to consolidate the crystal packing

Design and implementation of an integrated surface texture information system for design, manufacture and measurement

The optimised design and reliable measurement of surface texture are essential to guarantee the functional performance of a geometric product. Current support tools are however often limited in functionality, integrity and efficiency. In this paper, an integrated surface texture information system for design, manufacture and measurement, called “CatSurf”, has been designed and developed, which aims to facilitate rapid and flexible manufacturing requirements. A category theory based knowledge acquisition and knowledge representation mechanism has been devised to retrieve and organize knowledge from various Geometrical Product Specifications (GPS) documents in surface texture. Two modules (for profile and areal surface texture) each with five components are developed in the CatSurf. It also focuses on integrating the surface texture information into a Computer-aided Technology (CAx) framework. Two test cases demonstrate design process of specifications for the profile and areal surface texture in AutoCAD and SolidWorks environments respectively

Giant supercurrent states in a superconductor-InAs/GaSb-superconductor junction

Superconductivity in topological materials has attracted a great deal of interest in both electron physics and material sciences since the theoretical predictions that Majorana fermions can be realized in topological superconductors [1-4]. Topological superconductivity could be realized in a type II, band-inverted, InAs/GaSb quantum well if it is in proximity to a conventional superconductor. Here we report observations of the proximity effect induced giant supercurrent states in an InAs/GaSb bilayer system that is sandwiched between two superconducting tantalum electrodes to form a superconductor-InAs/GaSb-superconductor junction. Electron transport results show that the supercurrent states can be preserved in a surprisingly large temperature-magnetic field (T-H) parameter space. In addition, the evolution of differential resistance in T and H reveals an interesting superconducting gap structure