Solar Photocatalytic Degradation of 4‐Chlorophenol in Kaolinite Catalysts

This research applies semiconductor photocatalysts, which are formed by metal ion exchange on the surface of kaolinite catalyst with cations, to the study of photocatalytic degradation of 4‐chlorophenol. The analysis results of catalyst properties shows that, after sintering at 400 °C, kaolinite catalyst has a particle size of between 10–100 nm indicating the nano level of synthesized catalysts. Under the same condition, kaolinite‐Ag/Zn catalyst works better in degradation efficiency than single kaolinite‐Ag and kaolinite‐Zn catalysts. Kaolinite‐Zn catalyst declines in degradation efficacy after 150 minutes and performs poorer than the other three types of kaolinite catalysts. In the experiments of different amounts of catalysts, when the concentration exceeds 0.1 wt%, utilization of light energy and degradation efficiency will be reduced due to shielding effect. When at different pH values, the higher the pH value, the more OH‐will be released and that is beneficial for reaction with substances and the increase of reaction rate. Finally multivariate analysis proves that there is one determining factor that influences the photocatalytic degradation of 4‐chlorophenol in kaolinite catalysts, named as “the factor with intermediates competition degree,” the one affecting the 4‐CP degradation at different weight percentages that is referred to as the “shielding effect factor.”     

L-卡尼丁分子压印聚合物作为手性分离色谱固定相的研究

以L－卡尼丁为模板分子，分别以α－甲基丙烯酸和丙烯酰胺为功能单体，乙二醇二甲基丙烯酸酯为 剂，采用分子压印技术合成了对L－卡尼丁具有高选择性的分子压印聚合物。将所得聚合物用作高效液相色谱固定相，研究了它们对外消旋卡尼丁盐酸盐的拆分能力，分析结果表明，α－甲基丙烯酸作为功能单体所得聚合物对外消旋卡尼丁盐酸盐具有良好的拆分作用，其分离因子α为1．89。     

磷脂酰胆碱与牛血清白蛋白相互作用的FT-IR研究

利用傅立叶变换红外(FT-IR)和拉曼(FT-Raman)光谱研究了高浓度磷脂酰胆碱(PC)与牛血清白蛋白(BSA)的相互作用,及Eu3＋对该作用的影响.FT-IR结果显示,PC/BSA混合体系中二者的相互作用主要发生在PC头部极性基团,且这一作用随BSA含量的增加而增强,作用后蛋白质二级结构中α螺旋的比例有所增加. FT-Raman光谱说明PC与BSA的相互作用影响磷脂CH链的排列有序程度. PC/BSA/Eu3＋体系的红外光谱显示, Eu3＋与PC的磷氧键发生了强相互作用,并使蛋白α螺旋的比例进一步增加.     

Fully quantum mechanical energy optimization for protein-ligand structure

We present a quantum mechanical approach to study protein-ligand binding structure with application to a Adipocyte lipid-binding protein complexed with Propanoic Acid. The present approach employs a recently develop molecular fractionation with a conjugate caps (MFCC) method to compute protein-ligand interaction energy and performs energy optimization using the quasi-Newton method. The MFCC method enables us to compute fully quantum mechanical ab initio protein-ligand interaction energy and its gradients that are used in energy minimization. This quantum optimization approach is applied to study the Adipocyte lipid-binding protein complexed with Propanoic Acid system, a complex system consisting of a 2057-atom protein and a 10-atom ligand. The MFCC calculation is carried out at the Hartree-Fock level with a 3-21G basis set. The quantum optimized structure of this complex is in good agreement with the experimental crystal structure. The quantum energy calculation is implemented in a parallel program that dramatically speeds up the MFCC calculation for the protein-ligand system. Similarly good agreement between MFCC optimized structure and the experimental structure is also obtained for the streptavidin-biotin complex. Due to heavy computational cost, the quantum energy minimization is carried out in a six-dimensional space that corresponds to the rigid-body protein-ligand interaction.     

三正辛胺修饰电极伏安测定痕量金的研究

用化学修饰电极伏安测定痕量金,Kalcher K等曾采用阴离子交换剂碳糊修饰电极及打萨宗碳糊修饰电极检测100～300μg/L的金。本文采用三正辛胺(TOA)修饰玻碳电极,在1.5 mol/L介质中,Au(Ⅲ)在+0.16 V(vs SCE)处有一灵敏的不可逆还原峰。检出限为0.1μg/L。灵敏度比文献方法高千倍。Au(Ⅲ)浓度在5×10~(-7)～5×10~(-9)mol/L范围内峰高与浓度     

Progress on the application of electrochemiluminescence biosensor based on nanomaterials

In this review, we check out the number of published literature in the field of ECL biosensors trends during nearly a decade, and compare the research status of four different types of biosensors; summarize the application forms of nanomaterials in ECL biosensor. We have an overview of the building patterns and application example of the four main types of biosensors in the paper.     

中药片仔癀,六味地黄丸中的微量铬,铅和镉石墨炉原子吸收法测定

本文采用ＧＦ－ＡＡＳ加平台技术，基体改进剂，测定了中药片仔癀，六味地黄丸中铬、铅和镉的含量，铬、铅和镉的线性范围分别为０－０．８ｎｇ／ｍＬ，０－５０ｎｇ／ｍＬ，０－５ｎｇ／ｍＬ，回收率分别为１０２－１０３％，９９－１０１％，９７．５－９８％，本方法简便快速、准确。     

Development of a mild mercaptoethanol extraction method for determination of mercury species in biological samples by HPLC–ICP-MS

A mild, efficient and convenient extraction method of using 2-mercaptoethanol contained extractant solution combined with an incubator shaker for determination of mercury species in biological samples by HPLC–ICP-MS has been developed. The effects of the concentration of 2-mercaptoethanol, the composition of the extractant solution and the shaking time on the efficiency of mercury extraction were evaluated. The optimization experiments indicated that the quantitative extraction of mercury species from biological samples could be achieved by using 0.1% (v/v) HCl, 0.1% (v/v) 2-mercapoethanol and 0.15% (m/v) KCl extractant solution in an incubator shaker for shaking overnight (about 12 h) at room temperature. The established method was validated by analysis of various biological certified reference materials, including NRCC DOLT-3 (dogfish liver), IAEA 436 (tuna fish), IAEA MA-B-3/TM (garfish filet), IAEA MA-M-2/TM (mussel tissue), GBW 08193 (bovine liver) and GBW 08572 (prawn). The analytical results of the reference materials were in good agreement with the certified or reference values of both methyl and total mercury, indicating that no distinguishable transformation between mercury species had occurred during the extraction and determination procedures. The limit of detection (LOD) for methyl (CH₃Hg⁺) and inorganic mercury (Hg²⁺) by the method are both as 0.2 μg L⁻¹. The relative standard deviation (R.S.D.s) for CH₃Hg⁺ and Hg²⁺ are 3.0% and 5.8%, respectively. The advantages of the developed extraction method are that (1) it is easy to operate in HPLC–ICP-MS for mercury species determination since the extracted solution can be directly injected into the HPLC column without pH adjustment and (2) the memory effect of mercury in the ICP-MS measurement system can be reduced.     

Remarkably enhanced capacitance of ordered polyaniline nanowires tailored by stepwise electrochemical deposition

A stepwise deposition method was employed to create ordered polyaniline (PANI) nanowires with remarkably enhanced capacitance. Cyclic voltammetry, AC impedance, and galvanostatic charge/discharge cycling were employed to investigate the electrochemical performance of the PANI electrodes. The PANI-deposited electrode exhibits much higher capacitance than those prepared by one-step deposition method, which were mainly contributed from the unique nano structure of PANI and the increased biological, economical, and technical surface areas. The superior capacitive behaviors of the nano PANI electrodes show great potential in preparation of high efficient electrochemical capacitors or rechargeable batteries.     

An Environmentally Benign System for Synthesis of β-Hydroxylketones： L-Histidine Asymmetrically Catalyzed Direct Aldol Reactions in Aqueous Micelle and Water-like Media

The first histidine catalyzed direct aldol reactions of ketones with nitrobenzaldehydes in water and in poly（ethylene glycol） （PEG） were reported. It reveals that histidine is a good aldol catalyst for synthesis of β-hydroxylketones in water and in PEG, giving good to excellent yields of the respective products. Better enantioand regioselectivity were achieved using low molecular weight PEG as the media. The results show that histidine and PEG-200 or -300 may constitute a promising environmentally benign system for asymmetric synthesis of β-hydroxylketones.