制度性歧视与社会公正——以厦门农民工为例

本文以厦门农民工为考察对象,着重调查他们在就业中遭遇到的不公平对待现象和他们的反应,以此反思歧视性就业制度产生和存在的原因和困境,笔者希望能够借此逐渐消除中国对农民工就业的制度障碍,以建立一个公平、公正的就业环境。国家社科基金资助课题《中国东南沿海城市“外来散工”研究》成果之一

配位反应中的物种保护策略

从有机合成的官能团保护研究出发,通过实例探讨了金属或配体的保护策略分别对配体或金属反应性的作用,包括金属离子保护在络合滴定中的应用,金属离子配位保护下的单核、多核配合物和配位聚合物对配体反应性的影响,以及配位原子保护下的金属原子簇的反应性。国家自然科学基金项目(No.21073150); 国家重点基础研究发展计划(973)项目(No.2010CB732303); 国家基础科学人才培养基金项目(No.J1210014

The stable and uniform characteristics of nitrogen in nitrogen doped titanium dioxide nano photocatalytic particles

Conference Name:8th China International Nanoscience and Technology Symposium (Cinsts 09). Conference Address: Xiangtan, PEOPLES R CHINA. Time:OCT 23-27, 2009.N doped TiO(2) nano particles were prepared by heating TiO(2) nano particles in NH(3) + C(3)H(8) 5vol% atmosphere. The stability and uniformity characteristics of the doped N in the prepared N doped TiO(2) nano particles were studied by X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption (TPD). We concluded that the doped N was uniform from the surface to the inside of TiO(2) nano particles and found that the desorption peak of the doped N was more than 900 K in vacuum, showing its high stability and potential of visible light photocatalytic application for N doped TiO(2) nano particles

Synchrotron radiation based nuclear resonant vibrational spectroscopy:Applications

文章上篇介绍了核共振振动能谱学的基础理论和实验方法。本篇将着重介绍其在铁基化学和铁基生物化学研究中的应用实例:首先讨论单铁玉红氧还蛋白溶液样品和晶体样品的核振能谱以及它们的对比情况;然后由简入繁,系统地叙述核振能谱学方法在铁硫蛋白、氢化酶、固氮酶等一系列重要的以铁硫为基础的多铁蛋白研究中的应用和相关的研究成果;作为非铁硫类蛋白的代表,作者也简述了一氧化碳肌红蛋白的核振能谱。以上述实例为基础,本篇最后综述了该能谱方法在理论上和实验上突出的优越性和它在国内外的发展前景。In the article in the last issue(Part 1), we discussed the theoretical concept and experimental aspects of nuclear resonant vibrational spectroscopy(NRVS).In this issue, we will focus on its practical applications in iron-specific chemistry and biochemistry.As an introduction, the NRVS techniques for solution and crystal samples of single iron rubredoxin are first described and compared.Then the recent research results of multi-iron iron-sulfur proteins such as ferredoxins,hydrogenases and nitrogenases are discussed in detail.As an example of non-iron-sulfur proteins,carbon monoxide bound myoglobin is also presented.Based on the above examples, the theoretical and experimental advantages and potential of NRVS are reviewed, and its future prospects at home and abroad are discussed.美国国家卫生研究院基金会; 美国科学基金会; 美国能源部科学基金

Synchrotron radiation based nuclear resonant vibrational spectroscopy:Introduction

核共振振动能谱学(简称核振能谱)是一种以同步辐射为实验基础的新型的振动能谱学方法。与红外、拉曼等传统的振动光谱学方法相比,核振能谱在理论上和实验上具有一系列突出的特点和优越性,从而在各学科,特别是在铁基化学和铁基生物化学的研究中有着广泛的应用。文章分为上下两篇,上篇介绍核振能谱的基本概念、基本理论、实验方法和实验条件等基础内容,并以简单的四氯化铁离子([fECl4]-)为例,演示由原始核振能谱到振动态密度函数(PVdOS)的分析流程。在选材上,文章侧重先进性、代表性和实用性;在叙述上,考虑到非同步辐射专业研究者的阅读需要,文章突出实验科学和应用科学的内容,力求简单明了、通俗易懂。下篇将系统介绍该能谱学方法在化学与生物化学中的应用实例。Nuclear resonant vibrational spectroscopy(NRVS) is a synchrotron radiation based and relatively new vibrational spectroscopy.It has great potential in studying iron-specific chemistry and biochemistry due to its theoretical and experimental advantages compared with traditional Fourier transform infrared and resonant Raman spectroscopy.This article is divided into two parts, with the second part to appear in the next issue.In this issue, we will introduce the basic concepts and theory of NRVS, as well as its experimental methods and instruments.The procedure to obtain the partial vibrational density of states(PVDOS) from a raw NRVS spectrum will also be illustrated using the simple chemical ion [FeCl4]-as an example.The topics are selected according to their novelty, relevance and practical applications, and the discussions are organized for easy comprehension by nonspecialists.In the next issue, we will focus on the chemical and biochemical applications of NRVS

Study on the Bond Valence Parameters for Tungsten-oxygen Bonds

根据键价理论中的指数方程sij=exp[(R0 -rij) /B] ,利用晶体结构报告中不同氧化态n的 3 2 9个W—O键长数据 ,选取不同的B值对键价参数R0 进行了拟合 ,建立了一系列R0 —n线性方程 ,并进而得到与W氧化态无关的键价参数R0 =0 1896nm和B =0 0 2 8nm .与文献数据比较 ,本文拟合的键价参数取得了较好的键价和计算结果 ,讨论了几个应用的实例 .Based on the equation s ij=exp[(R 0-r ij)/B] of bond valence approach and 329 W—O bond length data in literature, linear equations of bond valence parameter R 0 with oxidation state n in different B for W—O bonds were established. The new bond valence parameters R 0=0 1896 nm and B=0 028 nm independent of n were also derived. The parameters fitted in this work were proved to be more suitable for the bond valence calculations. Applications of these parameters to some examples were illustrated.国家重点基础研究发展规划 (No.0 0 1CB1 0 890 6)资助项

The correlation between metal oxidation state and bond valence parameters for M-O bonds (M = V, Fe and Cu). A simple method to search for the metal oxidation-state independent parameter pairs

Based on the latest available crystal data and the reported bond valence parameters, the linear correlation between the bond valence parameter R-0 with B = 0.37A for M-O bonds (M = V, Fe and Cu) and the metal oxidation state n is shown for the first time. For V-O bonds, a linear equation of R-0 similar to n is perfectly established as R-0 = 0.0250n + 1.674 (n = 2-5). Similarly, a linear equation for Fe-O bonds is fitted as R-0 = 0.0335n + 1.648 (n = 2-4), as well as R-0 = 0.0855n + 1.482 (n = 1-3) for Cu-O bonds fitted properly. In addition, the linear correlation between R-0 and n within certain range of B values for V-O and Fe-O bonds is also established. Consequently, the oxidation-state independent parameters (R-0, B) of (1.788, 0.32 A) for V-O bonds and (1.795, 0.30 A) for Fe-O bonds can be derived from the zero slope of the R-0 similar to n straight lines. However, a similar parameter pair for Cu-O bonds cannot be found using this unique approach

基于自动化技术的大学生腧穴压痛知觉阈调查

压痛阈(pressure pain threshold,PPT)是引起身体疼痛的按压力度,压痛知觉阈(pressure pain consciousness threshold,PPCT)是刚能感觉到疼痛时的按压力度。压痛知觉阈常简称为压痛阈,相对的有压痛耐受阈,即刚超出对压痛的耐受时施加的按压力度。按压力度与按压物触端的质地、按压速度、接触面积、按压力、局部压强均有关。本文报道运用自制自动化按诊装置[1,2]对人体多个部位的腧穴

Syntheses of a Series of Lactato Cobalt Complexes and Their Interaction with Bovine Serum Albumin

合成和表征了系列乳酸钴配合物,测定二水二乳酸钴配合物的结构,配合物中乳酸的羟基和羧基配位键平均键长分别为0.206 0(2)nM和0.206 8(2)nM。当[CO(HlACT)2(H2O)2](2)或[CO(HlACT)2(PHEn)].2H2O(4)配合物与牛血清白蛋白(bSA=bOVInE SEruMAlbuMIn)相互作用后,红外光谱显示乳酸或邻菲咯啉的特征吸收消失,钴离子与bSA出现新的配位,初步推定乳酸或邻菲咯啉配体被bSA中的强配体所取代。A series of lactate cobalt complexes are synthesized and characterized by spectral and structural analyses,including [Co(Hlact)2(H2O)2]·H2O(1),[Co(Hlact)2(H2O)2](2),[Co(Hlact)(phen)(H2O)2]Cl(3) and [Co(Hlact)2(phen)]·2H2O(4)(Lactic acid=H2lact;1,10-phenanthroline=phen).Their interactions with Bovine Serum Albumin(BSA) are investigated with infra-red spectra.国家自然科学基金(No.20805041);国家重点基础研究发展计划(No.2010CB126504)资助项

Pure Ti-based Mixed Oxides Prepared from the Thermal Decompositions of Molecular Precursors of Peroxo Complexes Coordinated with Tris(hydroxycarbonylmethyl)amine Trivalent Anion Titanate(Ⅳ)

在pH =2 5～ 4 0的条件下 ,以四氯化钛、过氧化氢和氨三乙酸为原料反应得到四种过氧酸钛配合物 (NH4) 4 [Ti2 O (O2 ) 2 (ta) 2 ]·4H2 O (1) ,K4[Ti2 O(O2 ) 2 (ta) 2 ]·6H2 O (2 ) ,Sr2 [Ti2 O(O2 ) 2 (ta) 2 ]·10H2 O (3 )和Ba2 [Ti2 O(O2 ) 2 (ta) 2 ]·10H2 O (4 )(H3 ta =C6H6O6N) .配合物的EA ,UV vis,IR和X射线单晶分析表明它们含有相同的双核过氧氨三乙酸钛的阴离子结构 ,钛原子与过氧基团、四齿氨三乙酸和桥氧七配位 .3和 4中的阳离子锶和钡分别与周围的水分子和羧基氧形成九配位和十配位 .配合物 1,3和 4在空气中 60 0℃分解 ,XRD分析表明分别得到金红石型TiO2 ,SrTiO3 和四方BaTiO3 纯相 .Different peroxo titanate(Ⅳ) complexes coordinated with tris(hydroxycarbonylmethyl)amine trivalent anion including ammonium, potassium, strontium and barium salts (NH 4) 4[Ti 2O(O 2) 2(ta) 2]·4H 2O (1), K 4[Ti 2O~(O 2) 2~(ta) 2]·6H 2O (2), Sr 2[Ti 2O(O 2) 2(ta) 2]·10H 2O (3) and Ba 2[Ti 2O(O 2) 2(ta) 2]·10H 2O (4) were obtained directly from the triad system of TiCl 4-H 2O 2-H 3ta [H 3ta=tris(hydroxycarbonylmethyl)amine] in pH 2.5～4.0. These complexes were characterized with elemental analysis, UV-vis and IR spectra. X-ray structural analysis shows that all complexes contain a similar dimeric anion structure, in which titanium atom is coordinated heptagonally by a peroxo group, a tetradenatate tris(hydroxycarbonylmethyl)amine trivalent anion ligand and a bridging oxygen atom. The cation Sr 2+ and Ba 2+ are coordinated enneahedrally and decagonally by water molecules and carboxyl groups of tris~(hydroxycarbonylmethyl)amine trivalent anion ligand respectively. The ammonium, strontium and barium salts can be decomposed stoichiometrically into the expected low-temperature phases of rutile TiO 2, SrTiO 3 and tetragonal BaTiO 3 at the temperature of 600 ℃ respectively, which has been confirmed by XRD characterization.国家重点基础研究发展规划 (No.0 0 1CB1 0 890 6);; 国家自然科学基金 (No.2 0 0 2 1 0 0 2 )资助项