Structures that should be Described in Higher-Symmetry, Centrosymmetric Space Groups. Part 2. The Structures of [Ni(C_5H_4NO-2-CH=N-CH_2CH_2-N=CH-2-C_5H_4NO)(H_2O)_2]- (ClO_4)_2, {Ni[C_5H_4NO-2-CH=N-CH(CH_3)CH_2-N=CH-2- C_5H_4NO](H_2O)_2}

1　ＩＮＴＲＯＤＵＣＴＩＯＮＳｅｖｅｒａｌｉｎｃｏｒｒｅｃｔｓｐａｃｅｇｒｏｕｐｓｈａｖｅｂｅｅｎｒｅ ａｓｓｉｇｎｅｄｂｙｍａｋｉｎｇｕｓｅｏｆｓｉｍｕｌａｔｅｄｓｔｒｕｃｔｕｒｅｆａｃｔｏｒｓ;ｈｏｗｅｖｅｒ,ｔｈｅｃｒｕｘｏｆｔｈｉｓｏｒａｎｙｓｐａｃｅｇｒｏｕｐｒｅｖｉｓｉｏｎｉｓｔｈｅａｃｃｕｒａｔｅｒｅｐｏｒｔｉｎｇｏｆｔｈｅｓｐａｃｅｇｒｏｕｐａｎｄａｔｏｍｉｃｃｏｏｒｄｉｎａｔｅｓｏｆｔｈｅｉｎｃｏｒｒｅｃｔｌｙｄｅｔｅｒｍｉｎｅｄｓｔｒｕｃｔｕｒｅｓｉｎｃｅｔｈｅｔｒｕｅｓｔｒｕｃ…     

Synthesis and Crystal Structure of O,O'-Diisopropyl-5-(4-chlorophenyl)-1-hydroxy-2E,4E-pentadienylphosphonate

1　INTRODUCTIONAbscisicacid(ABA)isoneofplanthormoneswhichwasisolatedfromyoungcottonfruitsin1963[1].Itnotonlyinhibitsplantgrowth,butalsoprotectsplantsa-gainstdeprivationofwaterduringdroughtdays[2].Hydroxyalkylphosphonicacidsandtheirderivativesappeartobeveryimportantfortheirwidebiologicalactivitiesintheinhibitionofenzymes,fungicidesandplantgrowthregulation[3].Wedesignedandsynthesizedthetitlecompound4,theunsaturatedphosphonateanaloguesofABA,whichexhibitsplantinhibitoryactivityontheelongati…     

从非线性与统计物理多重角度探讨数值地震预测

在科技文献中,地震常被比喻为非线性动力学过程或统计物理中的相变过程.文章探讨了如何从非线性力学中的分岔理论以及统计物理内的朗道相变理论出发,从势磊穿越,临界涨落与临界慢化等多个角度来分析和了解地震发生的全过程.文章作者试图在这些非线性力学与统计物理的基础上,综合地震过程中在时间与空间上应出现的前兆,解释如何可能做出具有普适性的数值地震预测.     

Ultrafast Internal Conversion Dynamics of 2-Chloropyridine by Femtosecond Time-Resolved Photoelectron Imaging

Ultrafast internal conversion dynamics of 2-chloropyridine were studied by femtosecond time-resolved photoelectron imaging spectroscopy coupled with time-resolved mass spectroscopy. The ultrafast internal conversion from the second excited state (S2) to the first excited state (S1) via an adjacent conical intersection within (162±5) fs was clearly observed from the time-dependence of the photoelectron spectra. The subsequent deactivations involved the coupling of S2/S0(the ground state) and S1/S0 conical intersections, which occurred on a timescale of about (5.5±0.3) ps, and led to the internal conversion to the ground state from the S2 and S1 states.     

Species separation of binary colloidal mixtures in the multi-Gauss potential: Effect of depletion

For the asymmetrical colloidal mixture subject to a confining potential and an external multi-Gauss potential, the separation of species is studied based on the classical density functional theory of simple fluids. The multi-Gauss potential consists of several Gauss barriers, which are distributed along the axial direction with uniform distance. The barrier width,barrier distance, and barrier height are individually adjusted to investigate their effects on the species separation. From the numerical results, it is concluded that in each condition, the competition between the external potential and the depletion potential determines the phase equilibrium and the separation. Species separation appears only in the region where the depletion is dominant. On the contrary, both species are absent in the regions where the external potential takes the absolute advantage.     

Dendritic growth and solute trapping in rapidly solidified Cu-based alloys

Rapid solidification of binary Cu-22%Sn peritectic alloys and Cu-5%Sn-5%Ni-5%Ag quaternary alloys was accomplished by glass fluxing, drop tube and melt spinning methods. The undercooled, by glass fluxing method, Cu-22%Sn peritectic alloy was composed of α(Cu) and δ(Cu41Sn11) phases. If rapidly solidified in a drop tube, the alloy phase constitution changed from α(Cu) and δ(Cu41Sn11) phases into a single supersaturated (Cu) phase with the reducing of droplet diameter, and the maximum solubility of Sn in (Cu)...     

Synthesis of the Complex Fluoride LiBaF_3 through a Solvothermal Process

The complex fluoride LiBaF3 is solvothermally synthesized at 180℃ and characterized by means of X-ray powder diffraction, scanning electron microscopy, thermogravimetric analysis and infrared spectroscopy. In the solvothermal process, the solvents, mole ratios of initial mixtures and reaction temperature play important roles in the growth of the single crystal.     

Two New Triterpenoid Glycosides from Elsholtzia bodinieri Vant

Elsholtzia bodinieri Vant (Labiatae) named Feng-Wei-Cha or Dong-Zi-Su, is a Chinese medicinal plant, which is distributed in Yunnan and Guizhou Province of China. It is used in treatment of cough, headache, pharyngitis, fever and heptatitis1. In order to seek for the relative bioactive components, we studied the chemical constituents of E. bodinieri, which have not been reported in the literature. Two new triterpenoid glycosides, hederagenin-3-O-b-D-xylopyranoside (1), dodecandral-3-O…