分裂的正则Hom-Leibniz-Rinehart代数

作为Hom-Leibniz代数胚的代数类比, 本文引入Hom-Leibniz-Rinehart代数的概念. 证明了分裂的正则Hom-Leibniz-Rinehart代数$L$写成$L=U+\sum_{\gamma}I_\gamma$, 其中$U$为极大交换子代数$H$的子空间和$I_\gamma$为$L$的理想, 若$[\gamma]\neq[d]$, 满足$[I_\gamma, I_d]=0$. 随后分别发展了分裂Hom-Leibniz-Rinehart代数的根和权的连通技术.最后研究了紧致的正则Hom-Leibniz-Rinehart代数的结构.     

Use of p-dimethylaminobenzalhyde as a colored reagent for determination of procaine hydrochloride by spectrophotometry

Spectrophotometric determination of procaine hydrochloride is described. The procaine hydrochloride reacts with p-dimethylaminobenzalhyde in glacial acetic acid to form an Schiff base which is a yellow compound, and its maximum absorption wavelength is at 455nm, ₄₅₅=3.46×10⁴. The absorbance for procaine hydrochloride from 0.2 to 15 μg ml⁻¹ obeys Beer's law. The linear regression equation of the calibration graph is C=5.866A−0.02, with a linear regression correlative coefficient is 0.9994 and relative standard deviation (RSD) of 1.7%; the detection limit is 0.1 μg ml⁻¹; recovery is from 92.0 to 110.0%. Effects of reaction medium, temperature, gentamycin, beneylpenicillin, kanamycin, streptomycin, foreign ions, and stand for time on the determination of procaine hydrochloride have been examined. The results obtained by this method agreed with those by the official method (dead-stop titration). This method is rapid and simple, and can be used for the determination of procaine hydrochloride in injection solution of procaine hydrochloride.     

1,2-萘醌-4-磺酸钠为显色剂吸光度差值法测定盐酸普鲁卡因

1,2-萘醌-4-磺酸钠与盐酸普鲁卡因在pH 4.70的条件下反应,产物在300和483 nm处有两个吸收峰,可用两波长下吸光度差值测定盐酸普鲁卡因,本文对吸光度差值与分析物浓度之间的关系作了理论推导。吸光度差值(ΔA)与盐酸普鲁卡因质量浓度在2.0~36.0 mg/L范围内具有良好线性关系,线性回归方程为:ρ=37.092 0ΔA-0.332 3,线性相关系数为0.999 1,相对标准偏差为1.49%,回收率为97%~105%。试验了pH值、放置时间及干扰离子对测定的影响。此法简便、快速、准确,可用于注射液中盐酸普鲁卡因含量的测定,与药典方法对照,结果满意。     

Theoretical study on the molecule C30H20: five carbon–carbon single bonds linking a dodecahedrane cage and a pentaprismane cage

Using geometry optimization and DFT method at the B3LYP/6-31G* level of theory for C₃₀H₂₀, an equilibrium geometry is identified that has the form of polyhedral hydrocarbon with five carbon–carbon single bonds linking a dodecahedrane cage and a pentaprismane cage. Thus, this molecule is a tri-cage molecule with two pentaprismane cages and one dodecahedrane cage. Vibrational frequencies and the infrared spectrum are computed at the same level of theory. The heat of formation for C₃₀H₂₀ has been estimated in this paper. The heat of formation of C₃₀H₂₀ as well as the vibrational analysis indicates that this molecule enjoys sufficient stability to allow for its experimental preparation.     

A chelating resin containing S, N and O atoms: Synthesis and adsorption properties for Hg(II)

A novel chelating resin containing S, N and O atoms (PSME-EDA) was synthesized by using poly(2-hydroxyethylmercaptomethylstyrene) (PSME) and diethanolamine (EDA) as materials. Its structure was characterized by elemental analysis, Fourier transform-infrared spectra (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The adsorption of the resin for Hg²⁺ was investigated. The saturated adsorption capacity of PSME-EDA for Hg²⁺ could reach to about 1.1 mmol/g at 25 °C when the initial Hg²⁺ concentration was 0.02 mol/l. Some factors affecting the adsorption such as temperature, reaction time and ion concentration were also studied. The results showed that adsorption was controlled by liquid film diffusion. The increasing of temperature was beneficial to adsorption. The Langmuir model was better than the Freundlich model to describe the isothermal process. The values of ΔG, ΔH, and ΔS calculated at 25 °C were −7.99 kJ mol⁻¹, 22.5 kJ mol⁻¹ and 34.4 J mol⁻¹ K⁻¹, respectively. The adsorption mechanism of PSME-EDA resin for Hg(II) was confirmed by X-ray photoelectron spectroscopy (XPS).     

Coupling matrix element of electron self-exchange reactions in solution

On the basis of the common feature among the electron transfer process and the ion hydration process as well as the relevant experimental kinetic data of electron transfer reaction,a new accurate hydration potential function scheme for the determination of electron transfer coupling matrix element is presented.The coupling matrix element between two hydrated ions of the reacting system in solution is calculated.The results and the applicability of this scheme are discussed.     

Oxygen Atom Adsorption and Diffusion on Pd Low-index Surfaces and （311） Stepped Surface

Introduction Atom adsorption on transition metal surfaces has attracted special attention as a base for understanding the fundamental processes of oxidative catalysis. Particularly interesting is the adsorption and diffusion of oxygen on well-defined metal surfaces. An oxygen covered palladium surface, for example, plays a central role in several important reactions such as oxidation of carbon monoxide and ammonia. In particular, the (100), (111), (110) surfaces and the interactions with oxyge…     

Spectrofluorimetric determination of human serum albumin using a doxycycline-europium probe

A new spectrofluorimetric method is proposed for determination of human serum albumin (HSA) with the limit of detection at ng levels. Using doxycycline (DC)-europium (Eu³⁺) as a fluorescent probe, in a buffer solution of pH 10.2, HSA can remarkably enhance the fluorescence intensity of the DC-Eu³⁺ complex at 612 nm and the enhanced fluorescence intensity of Eu³⁺ is proportional to the concentration of HSA. Optimum conditions for the determination of HSA are also investigated. The linear ranges for HSA are 0-9.2 and 9.2-34.5 μg ml⁻¹ with limits of detection of 64 and 115 ng ml⁻¹, respectively. This method is simple, practical and relatively free of interference from coexisting substances, as well as much more sensitive than most of the existing assays. The determination results for human serum and urine samples are identical to those by the AOAO method, with relative standard deviations of five determinations of 1.1-3.6%. By the Rosenthal graphic method, the binding number and association constant of human serum albumin with the probe are 1.8 and 3.71×10⁵ l mol⁻¹, respectively.     

氧原子在Pt低指数面上的吸附和振动

应用原子和表面簇合物相互作用的5参数Morse势方法（简称5-MP）对O-Pt低指数表面体系进行了研究,并获得了全部临界点特性.计算结果表明,氧原子在Pt(100)面上只存在四重吸附态.在缺行重构的(110)面上,氧原子仍吸附于三重位,随着覆盖度的增加还会嵌切吸附于长桥位;通过分析三重态振动指纹性质的遗传和遗变,确认实验观察到的59.49和40.90 meV损失谱分别为氧原子在三重位和长桥位吸附态的表面垂直振动.     

Study of a fluorescence quenching mechanism of enoxacin and its determination in human serum and urine samples

The maximum emission wavelength of dopamine is 317 nm with excitation at 290 nm. The relative fluorescence intensity of dopamine decreased in the presence of enoxacin, which showed that fluorescence quenching occurred. The Stern-Volmer (S-V) plot showed a nonlinear relationship between the relative fluorescence intensity of dopamine and the concentration of enoxain. The quenching mechanism was studied and the results suggested that both dynamic and static quenching processes were responsible for the observed positive deviation in the S-V plot. When the S-V plot was modified by logarithm, the linear relationship was obtained between logF ₀/F and C in the range of 0.10 to 13.0 μg/mL (where F ₀ is the relative fluorescence intensity of dopamine, F is the relative fluorescence intensity of dopamine in the presence of enoxacin, and C is the concentration of enoxacin). The fluorescence quenching method for the determination of enoxacin was developed. The linear regression equation of the calibration graph of enoxacin was C = 13.70 (logF ₀/F) − 0.5836, with the correlation coefficient 0.9984. The detection limit was 2.0 ng/mL and the relative standard deviation was 2.52%. The effects of pH, the stability of dopamine in the presence of enoxacin, and foreign ions on the determination of enoxacin have been examined. The recovery of enoxacin was from 94.9 to 103.0% in a human serum sample and from 94.9 to 108.0% in a urine sample. The method is simple, rapid, and can be used for the determination of enoxacin in human serum and urine samples with satisfactory results. The text was submitted by the authors in English.