Transition-metal-free synthesis of 1,4-benzoxazepines via [4+3]-cycloaddition of para-quinone methides with azaoxyallyl cations

A formal[4+3]-cycloaddition reaction of ortho-hydroxyphenyl-substituted para-quinone methides(p-QMs)with in-situ generated azaoxyallyl cations is reported.The reaction occurs under very mild reaction conditions(transition-metal free,room temperature,cheap inorganic base)and provides a very efficient route to a series of biologically important 1,4-benzoxazepine derivatives in good to excellent yields.     

A Wire-Line Secure Communication System Based on CCFD Self-Interference Cancellation

This paper presents a design scheme of wire-line tele-phone system using self-interference (SI) cancellation technology in co-frequency co-time full-duplex (CCF...     

Non-Blind Image Deblurring Method Using Shear High Order Total Variation Norm

In this paper,we propose a shear high-order gradient(SHOG) operator by combining the shear operator and high-order gradient (HOG) operator.Compared with the HOG...     

手性大孔磷酸镓Hit-5的水热合成与晶体结构

本文采用水热合成法制备了一个三维手性大孔开放骨架磷酸镓Ga16P16O75·4[1,6-C6H18N2]·[C2H10N2]·2H2O(简称Hit-5).反应起始原料摩尔配比为:1 GaOOH:15 H3PO4:7.5 H2N(CH2)6NH2:0.5 C2H8N2:555 H2O.Hit-5属正交晶系,P21212空间群,晶胞参数:a=0.8671(1)nm,b=1.7945(1)nm,c=0.9101(1)nm,β=108.33(1)°,V=1.3443(2)nm3,Z=4.Hit-5的骨架是由Ga3P3六聚体和Ga4P4八聚体两个不同的二级结构单元通过共顶点联接构成三维纳米孔结构,在[001]方向呈现16-元环孔道.     

香花石形态所反映的一种可能的孪晶结构

香花石是我国发现的第一个新矿物,它的形态非常复杂.本文基于香花石形态上出现了左形与右形相聚的现象,对香花石形态进行了重新思考,认为同一单形的左形与右形不能相聚形成单晶体,只能形成孪晶,因此,对原香花石晶体图进行了一些修正,认为原香花石晶体图可能是一个孪晶图.这对深入认识晶体形态及晶体对称理论、澄清长期以来人们并没有足够重视的一些基本概念有重要意义.     

First Organic–Inorganic Hybrid Compounds Formed by Ge-V-O Clusters and Transition Metal Complexes of Aromatic Organic Ligands

Three compounds based on Ge-V-O clusters were hydrothermally synthesized and characterized by IR, UV-Vis, XRD, ESR, elemental analysis and X-ray crystal structural analysis. Both [Cd(phen)(en)]₂[Cd₂(phen)₂V₁₂O₄₀Ge₈(OH)₈(H₂O)]∙12.5H₂O (1) and [Cd(DETA)]₂[Cd(DETA)₂]_0.5[Cd₂(phen)₂V₁₂O₄₁Ge₈(OH)₇(0.5H₂O)]∙7.5H₂O (2) (1,10-phen = 1,10-phenanthroline, en = ethylenediamine, DETA = diethylenetriamine) are the first Ge-V-O cluster compounds containing aromatic organic ligands. Compound 1 is the first dimer of Ge-V-O clusters, which is linked by a double bridge of two [Cd(phen)(en)]²⁺. Compound 2 exhibits an unprecedented 1-D chain structure formed by Ge-V-O clusters and [Cd₂(DETA)₂]⁴⁺ transition metal complexes (TMCs). [Cd(en)₃]{[Cd(η₂-en)₂]₃[Cd(η₂-en)(η₂-μ₂-en)(η₂-en)Cd][Ge₆V₁₅O₄₈(H₂O)]}∙5.5H₂O (3) is a novel 3-D structure which is constructed from [Ge₆V₁₅O₄₈(H₂O)]¹²⁻ and four different types of TMCs. We also synthesized [Zn₂(enMe)₃][Zn(enMe)]₂[Zn(enMe)₂(H₂O)]₂[Ge₆V₁₅O₄₈(H₂O)]∙3H₂O (4) and [Cd(en)₂]₂{H₈[Cd(en)]₂Ge₈V₁₂O₄₈(H₂O)}∙6H₂O (5) (enMe = 1,2-propanediamine), which have been reported previously. In addition, the catalytic properties of these five compounds for styrene epoxidation have been assessed.     

Numerical Study on an RBF-FD Tangent Plane Based Method for Convection–Diffusion Equations on Anisotropic Evolving Surfaces

In this paper, we present a fully Lagrangian method based on the radial basis function (RBF) finite difference (FD) method for solving convection–diffusion partial differential equations (PDEs) on evolving surfaces. Surface differential operators are discretized by the tangent plane approach using Gaussian RBFs augmented with two-dimensional (2D) polynomials. The main advantage of our method is the simplicity of calculating differentiation weights. Additionally, we couple the method with anisotropic RBFs (ARBFs) to obtain more accurate numerical solutions for the anisotropic growth of surfaces. In the ARBF interpolation, the Euclidean distance is replaced with a suitable metric that matches the anisotropic surface geometry. Therefore, it will lead to a good result on the aspects of stability and accuracy of the RBF-FD method for this type of problem. The performance of this method is shown for various convection–diffusion equations on evolving surfaces, which include the anisotropic growth of surfaces and growth coupled with the solutions of PDEs.     

光子四维量子态隐形传输

多维量子纠缠态比二维纠缠态可加载更多的信息,多维量子系统是量子信息处理中一个很重要的资源.本文采用已实现的光子四维纠缠态,给出了光子四维量子态的张量表达式,并描述了四维量子态隐形传输的一般表示方法;通过讨论光子四维量子态系统的量子通道参数矩阵和测量矩阵的特性,得到实现完全传输和非零概率传输的充要条件.最后,本文给出在多种量子通道下的四维态的量子隐形传态方案,这一过程在张量分析表示下十分清晰明了.     

Benzothiadiazole-based Conjugated Polymers for Organic Solar Cells

Benzothiadiazole(BT) is an electron-deficient unit with fused aromatic core, which can be used to construct conjugated polymers for application in organic solar cells(OSCs). In the past twenty years, huge numbers of conjugated polymers based on BT unit have been developed,focusing on the backbone engineering(such as by using different copolymerized building blocks), side chain engineering(such as by using linear or branch side units), using heteroatoms(such as F, O and S atoms, and CN group), etc. These modifications enable BT-polymers to exhibit distinct absorption spectra(with onset varied from 600 nm to 1000 nm), different frontier energy levels and crystallinities. As a consequence, BT-polymers have gained much attention in recent years, and can be simultaneously used as electron donor and electron acceptor in OSCs, providing the power conversion efficiencies(PCEs) over 18% and 14% in non-fullerene and all-polymer OSCs. In this article, we provide an overview of BTpolymers for OSCs, from donor to acceptor, via selecting some typical BT-polymers in different periods. We hope that the summary in this article can invoke the interest to study the BT-polymers toward high performance OSCs, especially with thick active layers that can be potentially used in large-area devices.     

An MPI+OpenACC-Based PRM Scalar Advection Scheme in the GRAPES Model over a Cluster with Multiple CPUs and GPUs

A moisture advection scheme is an essential module of a numerical weather/climate model representing the horizontal transport of water vapor. The Piecewise Rational Method(PRM) scalar advection scheme in the Global/Regional Assimilation and Prediction System(GRAPES) solves the moisture flux advection equation based on PRM. Computation of the scalar advection involves boundary exchange, and computation of higher bandwidth requirements is complicated and time-consuming in GRAPES. Recently, Graphic...