Characterization of Cu（Ⅱ） Ion Adsorption Behavior of the Polyacrylic Acid-Polyvinylidene Fluoride Blended Polymer

A blended polymer adsorbent prepared using acrylic acid and polyvinylidene fluoride was used to remove copper from aqueous solutions. The polymer was prepared using thermally induced polymerization and phase inversion. The blended polymer was characterized by X-ray diffraction analysis （XRD）, environ- mental scanning electron microscopy （ESEM）, X-ray photoelectron spectroscopy （XPS）, and N2 adsorption/desorption experiments. The sorption data was fit to linearized adsorption isotherms of the Langmuir, Freundlich, and Dubinin-Radushkevich （D-R） isotherms models. The batch sorption kinetics was evaluated using pseudo-first-order, pseudo-second-order, and intraparticle diffusion kinetic reaction models. △H0 is greater than 0, AGo is lower than 0, and △S0 is greater than 0, which shows that the adsorption of Cu （Ⅱ） by the blended polymer is a spontaneous, endothermic process. The adsorption isotherm fits better to the Freundlich isotherm model and the pseudo-second-order kinetics model gives a better fit to the batch sorption kinetics. The adsorption mechanism is assumed to be ion exchange between the cupric ion and the carboxylic acid functional group of the blended polymer.     

动力学分光光度法同时测定Cu（Ⅱ）、Mg（Ⅱ）

本文应用动力学分光光度法,根据25℃,PH=9.50Cu(Ⅱ)和Mg(Ⅱ)与络合剂CLG的络合物与EDTA之间的络合取代反应的不同的反应速率,实现其同时测定。该法可用来测定Cu(Ⅱ)和Mg(Ⅱ)的标准混合物以及河水、井水和矿泉水。     

Pb（Ⅱ）－Cup络合物导数极谱波研究

在ＰＨ为５～６的ＨＡｃ－六次甲基四胺溶液中，Ｐｂ（Ⅱ）与铜铁试剂产生的络合物在单扫描示波极谱仪上可观察到一灵敏的导数极谱波，其峰电位为－０．６４Ｖ（ＶＳ，ＳＣＥ），峰电流与铅浓度在９．６×１０－８～５．８×１０－６ｍｏｌ·Ｌ－１范围内成线性关系，检测限为１．９×１０－６ｍｏｌ·Ｌ－１，用以测定铅锌矿中铅的结果良好．同时研究了形成铅－铜铁试剂络合物吸附波的条件和性质，并用极谱法测定其络合比为１：１．     

食品中痕量Cu(Ⅱ)、Pb(Ⅱ)的极谱测定

用单扫描极谱法研究了铜铁试剂(Cup)-六次甲基四胺(C6H12N4)-HAc体系的伏安行为,发现在pH为4.0~4.5,0.4 mol/L的六次甲基四胺中,铜(Ⅱ)、铅(Ⅱ)在铜铁试剂存在下,分别于-0.26 V(vs.SCE)-、0.58 V(vs.SCE)左右产生一尖锐、灵敏的二次导数极谱波.铜(Ⅱ)、铅(Ⅱ)的浓度分别在8.0×10-8~8.0×10-6mol/L、4.0×10-8~8.0×10-6mol/L的范围内与相应的峰电流成线性关系,检出限分别为1.0×10-8mol/L和6.0×10-9mol/L.该方法用于大米、大白菜中铜(Ⅱ)、铅(Ⅱ)浓度的测定,结果满意.     

城市大气重金属（Pb,Cd,Cu,Zn）污染及其在植物 …

通过对烟台市区不同大气污染区域绿化植物叶片中重金属Ｐｂ,Ｃｄ,Ｃｕ,Ｚｎ富积量和大气与土壤中相应重金属的含量研究分析发现,植物叶片中重金属Ｐｂ,Ｃｕ,Ｚｎ的富积与大气中Ｐｕ,Ｃｕ,Ｚｎ的相对含量呈显著的正相关,而植物叶片中Ｃｄ的富积量与大气中重金属的相对含量相关不显著,所研究的４种重金属的在植物叶片中的富积量与其生长土壤中的重金属的含量无相关性,研究证明,在所调查的５种市区绿化植物中以园叶片对大气     

Cu（Ⅱ）草酰胺衍生物热分解动力学研究

利用TG－DTG－DTA热分析技术，研究了N，N‘-双（氨烷基）草酰胺合铜（Ⅱ）配合物在动态空气气氛中的热稳定性；结合微分法（Achar法）和积分法（Coats-Radfen法）协同处理非等温TG数据，通过对比热分解动力学参数E和lnA,提出了配合物热分解反应机理；并由动力学补偿效应获得了E与lnA的数学表达式。     

Cu（Ⅰ）和Cu（Ⅱ）相互转化的热力学浅析

从热力学角度分析了Cu（I）和Cu（Ⅱ）在气态、固态和在溶液中的稳定性以及两的相互转化规律。     

Asymmetric epoxidation of <Emphasis Type="Italic">α</Emphasis>,<Emphasis Type="Italic">β</Emphasis>-unsaturated ketones using <Emphasis Type="Italic">α</Emphasis>,<Emphasis Type="Italic">α</Emphasis>-diarylprolinols as catalysts

Asymmetric epoxidation of α,β-unsaturated ketones has been extensively studied and several important procedures have been developed in the last decade. This review addresses the most significant advances in asymmetric epoxidation of α,β-unsaturated ketones using proline-derived α,α-diarylprolinols as catalysts. Special attention has been paid to the enantioselective epoxidation of chalcones, α,β-unsaturated trifluoromethyl, trichloromethyl ketones and β,γ-unsaturated α-keto esters based on the reseach of our group.     

The R- and AR-indices： Complementing the h-index

Based on the foundation laid by the h-index we introduce and study the R- and AR-indices. These new indices eliminate some of the disadvantages of the h-index, especially when they are used in combina-tion with the h-index. The R-index measures the h-core’s citation intensity, while AR goes one step further and takes the age of publications into account. This allows for an index that can actually in-crease and decrease over time. We propose the pair (h, AR) as a meaningful indicator for research evaluation. We further prove a relation characterizing the h-index in the power law model.     

Transpositional behaviour of the Ds element in the Ac/Ds system in rice

Insertional mutagenesis based on maize Activator/Dissociator (Ac/Ds) transposons is becoming a ma- jor approach used to produce a saturated mutant collection in rice. In this research, Ds-T-DNA trans- formed homozygotes were crossed with Ac-T-DNA transformed homozygotes in order to establish an Ac/Ds transposon system in rice. The successive investigation of Ds transposition from F1 to F5 gen- erations indicated that the frequencies of germinal transposition increased over successive genera- tions and reached 54.2% in F3 generation. The Ds transposition pattern revealed that a Ds transposition induced an approximately 170-bp deletion of T-DNA sequence and another Ds transposition carried a 272-bp T-DNA sequence. Using thermal asymmetric interlaced PCR (TAIL-PCR), some flanking se- quences of the Ds element were amplified. Analyses of 17 Ds-flanking sequences showed that five Ds were inserted into gene regions. The Ds could transpose not only to the linked sites but also to the unlinked sites. The frequency of inter-chromosomal transposition of Ds was 33.3%.     

Osmotically stress-regulated the expression of glutathione peroxidase 3 in Arabidopsis

Gene expression of glutathione peroxidase 3 (ATGPX3) in response to osmotic stress was analyzed in Arabidopsis using ATGPX3 promoter-glucuronidase (GUS) transgenic plants. High levels of GUS ex- pression were detected under osmotic stress in ATGPX3 promoter-GUS transgenic plants. Compared with the wild type, the growth and development of ATGPX3 mutants (atgpx3-1) were more sensitive to mannitol. In addition, the expression of RD29A, ABI1, ABI2 and RbohD in atgpx3-1 was induced by ABA stress. These results suggest that ATGPX3 might be involved in the signal transduction of osmotic stress.     

The permeability effect of microcystin-RR on <Emphasis Type="Italic">Escherichia coli</Emphasis> and <Emphasis Type="Italic">Bacillus subtilis</Emphasis>

Microcystins are a kind of cyclic hepatoxins produced by many species of cyanobacteria. Most previous work have been done on the toxic effects of microcystins on animals and plants. However, the reports about the effect of microcystins on microbial cells are very limited. In this work, the permeability of MC-RR on the cell outer membrane of Escherichia coli (E. coli) and Bacillus subtilis (B. subtilis) was discussed. The permeability effect of MC-RR on the cell outer membrane of E. coli and B. subtilis under different concentrations was demonstrated by a rapid and sustained reduction in the A₆₇₅ values of lysozyme-treated cells. The decrease of the absorbance values showed a time- and dose-effect. The extravasations of protein and carbonhydrate increased with the increment of the treated-concentration of MC-RR. The results showed that MC-RR could increase the permeability of cell outer membranes of E. coli and B. subtilis. The synergistic effects of MC-RR and lysozyme on bacteria indicated that MC-RR might play an ecological role in bacteria in combination with other substances in some aquatic environments.     

Functional analysis of the sbcD （dr1921 ） gene of the extremely radioresistant bacterium Deinococcus radiodurans

In eukaryotes, the Mre11-Rad50-Nbs1 (MRN) complex, which resides at the crossroads of DNA repair and checkpoint signaling, rapidly forms prominent foci at damage sites following double-strand break (DSB) induction. This complex carries out the initial processing of the DSB ends. Mutations in the genes that encode components of this complex result in DNA-damage hypersensitivity, genomic in- stability, telomere shortening, and aberrant meiosis. Therefore, the MR proteins are highly conserved during evolution. The bacterial orthologs of Mre11 and Rad50 are the SbcD and SbcC proteins, respec- tively. Deinococcus radiodurans, an extremely radioresistant bacterium, is able to mend hundreds of radiation-induced DSBs. The SbcD and SbcC proteins were identified as the products of the Dr1921 and Dr1922 genes. Disruption of the sbcD gene, by direct reverse-orientation insertional mutagenesis tech- nology, remarkably increases the cells’ sensitivity to various types of DNA damaging agents, such as ionizing radiation, ultraviolet irradiation, hydrogen peroxide, and mitomycin C. We also provide evidence that the drSbcD protein plays an important role in both growth and DNA repair in this organ- ism, especially in repair of DSBs generated after cellular exposure to 6000 Gy of IR. These results demonstrate that the drSbcD protein plays an important role in DSBs repair in D. radiodurans.