Chemical Non-equilibrium Simulation of Anode Attachment of an Argon Transferred Arc

Plasma Chemistry and Plasma Processing - The diffuse and constricted arc attachment modes to the anode of an argon wall-stabilized transferred arc are investigated using a 2D chemical...     

双温度氦等离子体输运性质计算

获得覆盖较宽温度和压力范围内的等离子体输运性质是进行等离子体传热和流动过程数值模拟的必要条件.本文采用Saha方程计算等离子体组分, 采用基于将Chapman-Enskog方法扩展到高阶近似的方法, 计算获得了电子温度(T_e)不等于重粒子温度(T_h)的情形下, 在300 K到40000 K的温度范围内氦等离子体的黏性、热导率和电导率. 研究结果表明压力和热力学非平衡参数(θ =T_e/T_h)对氦等离子体的输运性质有较大的影响. 在局域热力学平衡条件下,计算获得的氦等离子体输运性质和文献报道的数据符合良好.     

Capillary electrophoresis with end-column amperometric detection of urinary 8-hydroxy-2'-deoxyguanosine

Urinary 8-hydroxy-2'-deoxyguanosine (8OHdG) is an excellent marker of oxidative DNA damage. Until now, urinary 8OHdG has been measured by high-performance liquid chromatography with electrochemical detection. A simple and sensitive method for the analysis of urinary 8OHdG by capillary electrophoresis with end-column amperometric detection has been developed in our laboratory. A single-step solid-phase extraction procedure was optimized and used for extracting 8OHdG from human urine. To improve the sensitivity of this method, a new focusing technique based on a dynamic pH junction was used. The limit of detection was 20 nM (signal-to-noise ratio S/N = 3), the linear range was 50 nM-10 microM, and the correlation coefficient was better than 0.999. The relative standard deviation (RSD) was found to be 0.57% for migration time, and 4.79% for peak current. To show the usefulness of the method, the urinary concentration of 8OHdG in nine healthy persons and ten cancer patients was determined. The urinary concentration of 8OHdG in cancer patients was significantly higher than that in healthy persons.     

多光子电离下醇类团簇中的反应

应用Nd:YAG(Spectra-Physics LAB-170)脉冲激光器输出的355nm紫外激光实现了对甲醇、乙醇及正丙醇的多光子电离,对每一种样品通过质谱技术都观测到了两个质子化团簇离子系列:(R..3OH)nH 和(R1,2,3OH)n(H2O)H (R1,2,3代表CH2、CH2CH2及CH2CH3CH2),结合在HF/STO-3G和B3LYP/6-31G 水平上的从头计算对其反应通道做了分析,发现其产生经过了团簇内部的质子转移反应及离子-分子反应,且质子主要来自于羟基上的氢离子.并结合从头算分析了(R1,2,3OH)nH 的结构,给出了幻数团簇(R1,2,3OH)3H 的构型.同时对(R1,2,3)n(H2O)H 系列只在n值较大时出现做了相应的解释.     

铜取代Dawson结构杂多钨磷酸电荷转移配合物的合成与性质研究

Two new charge-transfer complexes, (DMAH)₁₀［CuP₂W₁₇O₆₂］·DMF·2H₂O and (DMAH)₁₄［Cu₂P₂W₁₆O₆₂］ have been prepared in aqueous solution from N,N′-dimethylaniline(DMA) and copper substituted polyoxotungstates with Dawson Structure, and characterized by elemental analysis, ICP, TG, IR, diffusion reflectance electronic spectra, polarography, and CV. The results indicate that the structure of anion has little change after the charge-transfer complexes are formed, but the characteristic vibrational bands have some red shift or blue shift. The charge transfer takes place under sunlight. There is a new absorption band at 625 nm in the solid reflectance electronic spectra of the complexes, it is ascribed to the IVCT (W(V)→W(Ⅵ) band of the reduced anion ［CuP₂W₁₇O₆₂］^10-. The conductivities at room temperature of title complexes are 3.6×10^-9 S·cm^-1 and 5.4×10^-9 S·cm^-1, respectively. Both of them are weak semiconductors.     

胆固醇MIPs的合成及其免疫吸附性能评价和应用

胆固醇MIPs的合成及其免疫吸附性能评价和应用;胆固醇;分子印迹聚合物;固相萃取;效率;生物样品     

The spin dynamics of the random transverse Ising chain with a double-Gaussian disorder

The dynamical properties of one-dimensional random transverse Ising model （RTIM） with a double-Gaussian disorder is investigated by the recursion method. Based on the first twelve recurrences derived analytically, the spin autocorrelation function （SAF） and associated spectral density at high temperature were obtained numerically. Our results indicate that when the standard deviation σg （or OrB） of the exchange couplings Ji （or the random transverse fields Bi） is small, no long-time tail appears in the SAE The spin system undergoes a crossover from a central-peak behavior to a collectivemode behavior, which is the dynamical characteristics of RTIM with the bimodal disorder. However, when σJ （or σB） is large enough, the system exhibits similar dynamics behaviors to those of the RTIM with the Gaussian disorder, i.e., the system exhibits an enhanced central-peak behavior for large σJ or a disordered behavior for large σB. In this instance, SAFs exhibit a similar long-time tail, i.e., C（t） ~ t ^-2 for large t. Similar properties are obtained when Ji （or Bi） satisfy the double-exponential distribution or the double-uniform distribution. Besides, when both the standard deviations and the mean values of the exchange couplings are small, the effects of the Gaussian random bonds may drive the system undergo two crossovers from a triplet state to a doublet state, and then to a collective-mode state.     

方波电泳电场驱动下液膜马达的电致流动特征

液膜马达作为一种新颖的实验装置在基础研究和技术应用方面都将会发挥着重要的作用, 深入研究各种条件下液膜马达的电致流动特征是非常有意义的. 本文从理论上研究了均匀恒定外电场中的液膜马达在方波电泳电场驱动下的动力学特征, 解析地给出了液膜转动的线速度随时空变化的规律. 理论结果表明, 液膜会随着电泳电场频率的增大由对称性往复转动逐渐转变为振动, 这不仅有助于从理论上认识液膜马达振动的物理根源, 也为在实际应用中设计液膜搅拌机提供了一种新思路.     

Synthesis, Crystal Structure of a New Co(II) Complex with Pyrazine-2,3,5,6-tetracarboxylic Acid

Abstract A new complex [Co(H₂pztc)(bpy)H₂O] (H₄pztc = pyrazine-2,3,5,6-tetracarboxylic acid, bpy = 2,2′-bipyridine) has been synthesized by hydrothermal reactions of Co(NO₃)₂ · 6H₂O with H₄pztc and bpy and characterized by IR and X-ray diffraction single crystal structure analysis. It belongs to monoclinic system, P2₁/c space group with a = 13.454(2) ?, b = 12.939(2) ?, c = 11.4993(19) ?, α = 90°, β = 111.640(3)°, γ = 90°. This complex is assembled into 3D supramolecular architecture by hydrogen bonds (O–H···O, C–H···O). Index Abstract A new complex of cobalt(II) with pyrazine-2,3,5,6-tetracarboxylic acid and 2,2′-bipyridine is assembled by intermolecular hydrogen bonds forming 2D layer and 3D supramolecular network.      

两种反式-9,10-二氢-9,10-二乙基蒽-11,12-二羧酸为主体的氢键包合物的合成与晶体结构

合成了反式-9,10-二氢-9,10-二乙基蒽-11,12-二羧酸(EADA)及其与硼酸共同构建主体晶格的正四丁基铵阳离子管状包合物(n-C4H9)4N C18H13O-4?B(OH)3(1)和(n-C4H9)4N C18H13O-4(2),并通过单晶X射线衍射法对其进行了晶体结构测定.结果表明,晶体1属单斜晶系,P2(1)/c空间群,晶胞参数a=1.5699(1)nm,b=0.9955(6)nm,c=2.2933(1)nm,β=109.962(3)°,Z=4,R1=0.0434,wR=0.0759;晶体2属单斜晶系,C2/c空间群,晶胞参数a=1.4005(3)nm,b=1.2821(2)nm,c=1.7657(3)nm,β=100.388(1)°,Z=4,R1=0.0584,wR=0.0966.在晶体1中,EADA阴离子和硼酸分子的氢键四聚体链交错平行排列,生成具有矩形截面的管道式主体晶格,每个管道内包含了两列规则排列的正四丁基铵阳离子(n-C4H9)4N .在晶体2中,相互独立的EADA阴离子交错排列形成类蜂巢形截面的管道式主体晶格,正四丁基铵阳离子形成Z形长列被包合在这些管道里,阳离子的烃链穿插在管道壁中.