阴离子存在下(OEP)MG(Ⅱ)的电化学氧化机理研究

用电化学滴定和现场光谱电化学方法研究考察了DCE中OH^-,F^-和Cl^-等阴离子存在下的(OEP)Mg(Ⅱ)的电极氧化过程.发现阴离子能与(OEP)Mg(目)轴向配位,形成五配位化合物,从而引起(OEP)Mg(Ⅱ)的氧化峰电位的负移;在生成二价环阳离子的过程中伴随后行化学反应.获得了反应产物的氧化还原峰电位.     

金属卟啉催化有机物与CO2的电羧化反应(III)

有机物与CO2直接电数化存在着过电位高电流效率低的缺点［1，2］．我们曾首次报道了金属卟啉对电羧化的催化[3]，证明其具有明显的催化作用．这种催化作用，类似于生物体中酶活性中心金属对批的作用，是对生物过程的模拟．通过研究酶在生物体中作用过程知，血红素、VB12，细胞色素P450叶绿素等，其平面轴向均有特定的配体，特定配体的轴向效应增强了活性中心的作用．为了增加金属叶琳催化电数化的活性，本文选用十二种生物肽和氨基酸以及四种有机碱作为轴向配体，在研究中以测定馆点（m．P．）、红外光谱（IR）、紫外吸收光谱（UV、气相…     

Experimental and theoretical investigation of stable diastereomeric conformations of biscarboline amides in solution

Stable axial conformations generally exist only when the single bond's (axis') rotation was sterically hindered in solution. Herein, we firstly show that two stable conformations could be observed in solution by ¹H and ¹³C NMR experiments when the single bond rotates freely. Its coalescence temperature was measured up to 120?°C when we took compound 13 as an example. The ratio of the two stable conformations was computed using quantum methods. The predicted results matched with the experimental results well. The conversion barrier between two conformers was estimated by potential energy scan (PES) and transition state (TS) calculations at the B3LYP/6-311 + G(d) level. Furthermore, its stereochemistry was also well studied by comparing theoretical electronic circular dichroism (ECD) spectra with the experimental one.     

Fractal axicons

Cantor rings are rotational symmetric pupils that are generated from a Cantor set of a given level of growth. These pupils have certain fractal properties. For example, it is known that when illuminated by a general spherical wavefront they provide self-similar patterns at transverse planes in the Fraunhofer region. In this paper, we study the response of Cantor rings when illuminated by a Bessel light beam conforming what we call fractal axicons. It is shown that, with this kind of illumination a close replica of the radial profile of the pupil is obtained along the optical axis, i.e., we show that the axial behaviour of these pupils has self-similarity properties that can be correlated to those of the diffracting aperture. The influence of several construction parameters is numerically investigated.     

Charged particle production and correlations at high transverse momentum at the CERN intersecting storage rings

We study the production of identified charged particles in pp collisions at a c.m. energy of 63 GeV in events with an identified high-p_T trigger particle. The measurements were performed at the CERN Intersecting Storage Rings using the Axial Field Spectrometer.Production ratios are presented as a function of p_T in the range 2.5 to 8 GeV/c.     

Kinetic Studies on Axial Coordination Reaction of Tetraphenylporphinatocobalt（Ⅱ） Chloride

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Assembling tetrapyrrole derivatives through axial coordination

Bis(4-pyridinolato) silicon(IV) phthalocyanine (1) binds with a series of zinc(II) tetrapyrrole derivatives with the two pyridyl ligands forming the corresponding 1:2 or 1:1 molecular assemblies. The molecular structure of the first axially linked trinuclear phthalocyanine-porphyrin array has also been determined.     

Energetics and conserved quantity of an axially moving string undergoing three-dimensional nonlinear vibration

Nonlinear three-dimensional vibration of axially moving strings is investigated in the view of energetics. The governing equation is derived from the Eulerian equation of motion of a continuum for axially accelerating strings. The time-rate of the total mechanical energy associated with the vibration is calculated for the string with its ends moving in a prescribed way. For a string moving in a constant axial speed and constrained by two fixed ends, a conserved quantity is proved to remain unchanged during three-dimensional vibration, while the string energy is not conserved. An approximate conserved quantity is derived from the conserved quantity in the neighborhood of the straight equilibrium configuration. The approximate conserved quantity is applied to verify the Lyapunov stability of the straight equilibrium configuration. Numerical simulations are performed for a rubber string and a steel string. The results demonstrate the variation of the total mechanical energy and the invariance of the conserved quantity.     

Influences of phase shift on superresolution performances of annular filters

This paper investigates the influences of phase shift on superresolution performances of annular filters. Firstly, it investigates the influence of phase shift on axial superresolution. It proves theoretically that axial superresolution can not be obtained by two-zone phase filter with phase shift π, and it gets the phase shift with which axial superresolution can be brought by two-zone phase filter. Secondly, it studies the influence of phase shift on transverse superresolution. It finds that the three-zone phase filter with arbitrary phase shift has an almost equal optimal transverse gain to that of commonly used three-zone phase filter, but can produce a much higher axial superresolution gain. Thirdly, it investigates the influence of phase shift on three-dimensional superresolution. Three-dimensional superresolution capability and design margin of three-zone complex filter with arbitrary phase shift are obtained, which presents the theoretical basis for three-dimensional superresolution design. Finally, it investigates the influence of phase shift on focal shift. To obtain desired focal shifts, it designs a series of three-zone phase filters with different phase shifts. A spatial light modulator (SLM) is used to implement the designed filters. By regulating the voltage imposed on the SLM, an accurate focal shift control is obtained.     

用ICP-AES双向观测同时测定土壤、沉积物和植物中常、微量元素

采用水平炬管设计的Optima3000DV全谱直读等离子体发射光谱仪 ,利用端视与侧视观测方式相结合 ,多元光谱拟合 (MSF)校正光谱干扰 ,用纯标准溶液配制混合标准系列作校准曲线 ,同时测定了土壤、沉积物和植物中Al、Ca、K、Mg、Na、Fe、Ti、As、Cd、Co、Cu、Mn、Mo、Ni、P、Pb、V、Zn18个常量、微量元素。经几个国家标准样品的验证 ,测定结果与推荐值基本相符 ,实际样品回收率土壤在92%～105 %之间 ,蔬菜在87.8%～104%范围。相对标准偏差分别为0.28%～4.23 %和0.26 %～3.66%。