物体内部三维位移场分析的数字图像相关方法

提出了物体内部三维位移场的数字图像相关分析方法，对物体变形前后，或连续变形的两个相邻状态的内部三维结构的数字图像，通过相关运算获得三维位移场.文中给出了三维相关法的体搜索窗口、相关函数及亚像素运算的相关系数拟合函数.数字模拟结果证明了三维相关法的正确性及可靠性.位移计算精度为0.02像素. 关键词： 数字图像相关 三维相关 亚像素     

A new naphthoquinone and other antibacterial constituents from the roots of Xanthium sibiricum

Reinvestigating the chemical constituents of the roots of Xanthium sibiricum led to the isolation of a new naphthoquinone (1), together with 13 known compounds (2–14). Their structures were elucidated by using spectroscopic analyses, including HR-ESI-MS, 1D and 2D NMR, and by comparing their NMR data with those of related compounds. Compound 1 showed moderate antibacterial activity against Escherichia coli, Bacillus subtilis, Micrococcus tetragenus and Staphylococcus aureus, while 6 and 12 showed stronger antibacterial activity than the positive control ciprofloxacin against E. coli, with minimum inhibitory concentration values of 0.17 and 0.35 μg/mL, respectively.     

Electronic structure and magnetism in full-Heusler compound Mn2ZnGe

The first-principle calculations within density functional theory are used to investigate the electronic structure and magnetism of the Mn₂ZnGe Heusler alloy with CuHg₂Ti-type structure. The half-metallic ferrimagnets (HMFs) in Mn₂ZnGe are predicted. The energy gap lies in the minority-spin band for the Mn₂ZnGe alloy. The calculated total spin magnetic moment is −2μ_B per unit cell for Mn₂ZnGe alloy, the magnetic moments of Zn and Mn(B) are antiparallel to that of Mn(A), and we also found that the half-metallic properties of Mn₂ZnGe are insensitive to the dependence of lattice within the wide range of 5.69 and 5.80 Å where exhibiting perfect 100% spin polarization at the Fermi energy.     

Diffusion of aluminum in MgO： A thermodynamic approach study

We have applied a thermodynamical model to calculate the diffusion coefficient of aluminum in MgO with the aid of bulk elastic properties. Our calculated diffusivities as a function of temperature and pressure are compared with the existing results derived from experimental or theoretical investigations. We find that the present model provides a satisfactory estimation for the activation volume and the activation enthalpy.     

TFA-catalyzed C–N bond activation of enamides with indoles: efficient synthesis of 3,3-bisindolylpropanoates and other bisindolylalkanes

An efficient TFA-catalyzed cleavage of C–N bonds in alkylation of indoles by tertiary enamides was described. A variety of bisindolylalkane derivatives, especially 3,3-bisindolylpropanoates, were expeditiously synthesized in good yields.     

Exact Solutions and Coherence Structures of Generalized Breor-Kaup Equations

Using the mapping method based on q-deformed hyperbolic functions, the exact solutions of generalized Breor-Kaup equations are obtained. Based on the solutions, two coherent structures, periodic-branch kink and nonpropagating kink, have been obtained. Moreover, one solitonal interaction form, two line solitons interaction on the kink background, has been found.     

The Influence of the Renormalization Condition to the Equation of State of the Nuclear Matter

In the relativistic σ-ω model, the influences of the parameters b, c, d in the potential U(σ) = (1/2!)bo2 - -(1/3!)cσ3 (1/4!)dσ4 to the incompressibility, effective mass and binding energy of the nuclear matter are studied in detail.The calculation of equation of state of nuclear matter shows that the values of b, c, d depend on the renormalization condition, we also find that a soft equation of state of nuclear matter can be obtained in a suitable renormalization condition, and the experimental incompressibility coefficient can be reproduced. These results are also used to study the thermal properties of hot A-resonant nuclear matter.self-interaction of σ meson, renormalization, hot and dense hadronic matter ``     

The complex Monge–Ampère equation with infinite boundary value

In this article we consider the complex Monge–Ampère equation with infinite boundary value in bounded pseudoconvex domains. We prove the existence of strictly plurisubharmonic solution to the problem in convex domains under suitable growth conditions. We also obtain, for general pseudoconvex domains, some nonexistence results which show that these growth conditions are nearly optimal.     

微波辐射下秸秆纤维微观结构的变化

利用原子力显微镜(AFM)对微波处理前后秸秆纤维表面的变化进行了研究,并结合XRD和FTIR研究了处理前后其化学结构及结晶形态的变化情况。结果表明,未经微波处理的秸秆纤维表面比较光滑,平均粗糙度(Ra)为(86.7±6.335)nm,均方根粗糙度(Rq)为(141.1±9.055)nm;经微波处理的秸秆纤维表面比较粗糙,并出现许多细小孔洞,其Ra为(445.0±28.14)nm,Rq为(558.9±33.458)nm,微波辐射处理前后秸秆纤维的表面形态差异较大。经微波辐射处理后,秸秆纤维在2θ=22.3°处的衍射峰移至21.8°,且峰宽稍有增加,在38.1°、44.3°、64.6°、78.9°处出现的4个衍射峰,除强度稍有增强,其峰形和位置与未经处理秸秆纤维的衍射峰基本一致,表明微波处理没有改变纤维的结晶形态。FTIR光谱表明,微波处理样中未产生新的官能团,但分子间氢键及分子内氢键发生变化。微波作用未引起秸秆纤维化学结构的变化。     

Coordination networks from Cu cations and tetrakis(methylthio)benzenedicarboxylic acid: tunable bonding patterns and selective sensing for NH(3) gas

This paper aims to illustrate the rich potential of the thioether-carboxyl combination in generating coordination networks with tunable and interesting structural features. By simply varying the ratio between Cu(NO(3))(2) and the bifunctional ligand tetrakis(methylthio)benzenedicarboxylic acid (TMBD) as the reactants, three coordination networks can be hydrothermally synthesized in substantial yields, which present a distinct evolution with regard to metal-ligand interactions. Specifically, Cu(TMBD)(0.5)(H(2)TMBD)(0.5)·H(2)TMBD (1) was obtained with a relatively small (1:1) Cu(NO(3))(2)/TMBD ratio, and crystallizes as an one-dimensional (1D) coordination assembly based on Cu(I)-thioether interactions, which is integrated by hydrogen-bonding to additional H(2)TMBD molecules to form a three-dimensional (3D) composite network with all the carboxylic acid and carboxylate groups remaining uncoordinated to the metal ions. A medium (1.25:1) Cu(NO(3))(2)/TMBD ratio leads to compound Cu(2)TMBD, in which Cu(I) ions simultaneously bond to the carboxylate and thioether groups, while an even higher (2.4:1) Cu(NO(3))(2)/TMBD ratio produced a mixed-cation compound Cu(II)(2)OHCu(I)(TMBD)(2)·2H(2)O (2), in which the carboxylic groups are bonded to (cupric) Cu(II) ions, and the thioether groups to Cu(I). Despite the lack of open channels in 2, crystallites of this compound exhibit a distinct and selective absorption of NH(3), with a concomitant color change from green to blue, indicating substantial network flexibility and dynamics with regards to gas transport.