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Isothermal Crystallization Kinetics and Crystalline Morphologies of Poly(butylene adipate-co-butylene 1,4-cyclohexanedicarboxylate)Copolymers

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chinese Journal of Polymer Science 2018年第6期36卷 756-764页

作者： Fei Liu De-quan chi Hai-Ning Na Jin Zhu Ningbo Key Laboratory of Polymer Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China College of Materials Science and Engineering Qingdao University of Science and TechnologyQingdao 266042China

In this study, the isothermal crystallization kinetics and crystalline morphology of poly（butylene adipate-co-butylene 1,4-cyclohexanedicarboxylate）（PBAC）, which refers to a copolyester containing a non-planar ring structure, were investigated by differential scanning calorimetry and polarized optical microscopy, and compared with those of neat poly（butylene 1,4-cyclohexanedicarboxylate）（PBC）. The results indicate that the introduction of butylene adipate（BA） unit into PBAC did not change the intrinsical crystallization mechanism. But, the crystallization rate and ability, and equilibrium melting temperature of PBAC copolymers were reduced. All PBC and PBAC copolymers could only form high density of nucleation from melt at given supercooling, while no Maltese cross or ring-banded spherulites could be observed. PBAC copolymers with a high amount of BA unit became amorphous after quenching with liquid nitrogen from melt, while PBC and PBAC copolymers with a low amount of BA unit could still form a large amount of nuclei under the same treatment.

关键词： Poly(butylene adipate-co-butylene 1 4-cyclohexanedicarboxylate) Isothermal crystallization kinetics Crystalline morphology

Study on the Structural Effect of Maltoligosaccharides on Cytochrome c Complexes Stabilities by Native Mass Spectrometry

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Natural Products and Bioprospecting 2018年第1期8卷 57-61页

作者： quan chi Ying-Zhi Liu Xian Wang Key Laboratory of Analytical Chemistry of the State Ethnic Affairs Commission College of Chemistry and Materials ScienceSouth-Central University for NationalitiesWuhanHubei 430074People’s Republic of China

Noncovalent interactions between ligands and targeting proteins are essential for understanding molecular mechanisms of *** this work,we investigated the interaction of Cytochrome c(Cyt c)with maltoligosaccharides,namely maltose(Mal Ⅱ),maltotriose(Mal Ⅲ),maltotetraose(Mal Ⅳ),maltopentaose(Mal Ⅴ),maltohexaose(Mal Ⅵ)and maltoheptaose(Mal Ⅶ).Using electrospray ionization mass spetrometry(ESI-MS)assay,the 1:1 and 1:2 complexes formed by Cyt c with maltoligosaccharide ligand were *** corresponding association constants were calculated according to the deconvoluted *** order of the relative binding affinities of the selected oligosaccharides with Cyt c were as MalⅢ>MalⅣ>MalⅡ>MalⅤ>MalⅥ>MalⅦ.The results indicated that the stability of noncovalent protein complexes was intimately correlated to the molecular structure of bound *** relevant functional groups that could form H-bonds,electrostatic or hydrophobic forces with protein’s amino residues played an important role for the stability of protein *** addition,the steric structure of ligand was also critical for an appropriate interaction with the binding pocket of proteins.

关键词： Electrospray ionization mass spectrometry Maltoligosaccharides Cytochrome c complexes Structure-binding relationship

Growth and Cd Accumulation of Orychophragmus violaceus as Affected by Inoculation of Cd-Tolerant Bacterial Strains

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Pedosphere 2014年第3期24卷 322-329页

作者： LIANG Xia HE chi-quan NI Gang TANG Gui-E CHEN Xue-Ping LEI Yan-Ru School of Environmental and Chemical Engineering Shanghai University

Beneficial interactions between microorganisms and plants, particularly in the rhizosphere, are a research area of global interest. Four cadmium(Cd)-tolerant bacterial strains were isolated from heavy metal-contaminated sludge and their effects on Cd mobility in soil and the root elongation and Cd accumulation of Orychophragmus violaceus were explored to identify the capability of metalresistant rhizobacteria for promoting the growth of O. violaceus roots on Cd-contaminated soils. The isolated strains, namely, Bacillus subtilis, B. cereus, B. megaterium, and Pseudomonas aeruginosa, significantly enhanced the plant Cd accumulation. The Cd concentrations in the roots and shoots were increased by up to 2.29- and 2.86-fold, respectively, by inoculation of B. megaterium, as compared with the uninoculated control. The bacterial strains displayed different effects on the shoot biomass. Compared with the uninoculated plants, the shoot biomass of the inoculated plants was slightly increased by B. megaterium and significantly decreased by the other strains. B. megaterium was identified as the best candidate for enhancing Cd accumulation in O. violaceus. Thus, this study provides novel insight into the development of plant-microbe systems for phytoremediation.

关键词： heavy metals phytoremediation plant-microbe systems rhizobacteria soil contamination

Fluoro-functionalized plant biomass adsorbent:Preparation and application in extraction of trace perfluorinated compounds from environmental water samples

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Journal of Environmental Sciences 2024年第3期137卷 703-715页

作者： Xi Tan Yan Shi Chun-Feng Ma quan chi Yu-Hang Yang Wen-Xiang Zhang Hua-Ming Xiao Xian Wang Key Laboratory of Analytical Chemistry of the State Ethnic Affairs Commission School of Chemistry and Materials ScienceSouth-Central Minzu UniversityWuhan 430074China School of Pharmaceutical Sciences South-Central Minzu UniversityWuhan 430074China Key Laboratory of Oilseeds Processing of Ministry of Agriculture Hubei Key Laboratory of Lipid Chemistry and NutritionOil Crops Research Institute of the Chinese Academy of Agricultural SciencesWuhan 430062China

Perfuorinated compounds(PFCs)are toxic and widely present in the environment,and therefore effective adsorbents are required to remove PFCs from environmental *** the present study,a new type of fuorinated biomass materials was synthesized via an ingenious fuorosilanization *** adsorbents were applied for the adsorption of 13typical PFCs,including perfuorocarboxylic acids(PFCAs)and perfuorosulfonic acids(PFSAs).By comparing their adsorption performance,Fluorinated cedar slag(FCS)was discovered to have the best absorption efficiency and enabled highly efficient enrichment of *** adsorption recovery of FCS with the investigated PFCs is greater than 90%under the optimal adsorption *** to the high affinity of F-F sorbent-sorbate interaction,FCS had good adsorption capacities of PFCs from aqueous solution,with the maximum adsorption capacity of 15.80 mg/g for PFOS and 10.71 mg/g for PFOA,***,the adsorption time could be achieved in a short time(8 min).Using the FCS absorbent,an innovative FCS-solid phase extraction assisted with high performance liquid chromatography-electrospray-tandem mass spectrometry(FCS-SPE-HPLC-ESI-MS/MS)method was first developed to sensitively detect PFCs in the environmental water *** intra-day and inter-day recovery rates of the 13 compounds ranged from 90.7%-104.3%,with the RSD of 2.1%-4.7%(intra-day)and 2.5%-8.5%(inter-day),*** research demonstrates the potential of the newly fuoro-functionalized plant biomass to adsorb PFCs from environmental water,with the advantages of high adsorption efficiencies,high antiinterference,easy operation and low economic cost.

关键词： Fluoro-functionalized biomass Perfuorinated compounds(PFCs) Adsorption efficiency Mass spectrometry(MS) Fluorinated cedar slag(FCS)

quantitative‑Profling Method of Serum Steroid Hormones by Hydroxylamine‑Derivatization HPLC-MS

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Natural Products and Bioprospecting 2019年第3期9卷 201-208页

作者： Qi Liu quan chi Ru-Ting Fan Hui-Dong Tian Xian Wang Key Laboratory of Analytical Chemistry of the State Ethnic Afairs Commission College of Chemistry and Materials ScienceSouth-Central University for NationalitiesWuhan 430074HubeiPeople’s Republic of China

A sensitive and rapid high performance liquid chromatography-mass spectrometry(HPLC-MS)method was developed and validated for simultaneous quantifcation of ten steroid hormones,including estrogens,androgens,progesterones,and corticosteroids four classes of *** following ten steroid hormones were analyzed:progesterone,21-deoxycortisol,estrone,4-androstenedione,testosterone,dihydro-testosterone,androstenone,dehydroepiandrosterone,corticosterone and *** deuterated isotopes were used as internal standards for *** preparation with and without derivatization were performed after liquid-liquid extraction,and the corresponding results were compared according to sensitivity and *** derivatization was found to improve the ionization efciency of the analytes for electrospray ionization MS *** gradient of mobile phase and experimental parameters for HPLC separation were *** lower limits of quantifcation were in the range of 0.05-5 ng mL^(−1) with wide linear range for the ten steroid *** intra-day precisionchieved,where within the acceptance limits of the FDA *** HPLC-MS analysis time was 6 *** method enables simultaneous quantifcation of steroids in human *** will be helpful for the serum steroid profling in order to understand various endocrinology diseases.

关键词： Steroids Derivatization High performance liquid chromatography–mass spectrometry(HPLC-MS) quantitative-profling

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铁卟啉与活性氮的相互作用

化学通报 2010年第1期73卷 18-23页

作者：池泉中南民族大学化学与材料科学学院武汉430074

在活性氮(RNS)与蛋白质的相互作用过程中,含铁卟啉蛋白/铁卟啉可以催化RNS转化为惰性的NO3-,阻止蛋白质的硝化;同时,含铁卟啉蛋白/铁卟啉也可通过高价铁氧化物及.NO2的产生来加速蛋白质的硝化。生理条件下,血红蛋白、肌红蛋白等含铁卟... 详细信息

在活性氮(RNS)与蛋白质的相互作用过程中,含铁卟啉蛋白/铁卟啉可以催化RNS转化为惰性的NO3-,阻止蛋白质的硝化;同时,含铁卟啉蛋白/铁卟啉也可通过高价铁氧化物及.NO2的产生来加速蛋白质的硝化。生理条件下,血红蛋白、肌红蛋白等含铁卟啉蛋白可清除多余的RNS;氧化应激条件下,过氧化物酶等含铁卟啉蛋白可以不同的方式催化加速RNS对蛋白质的硝化。

关键词：活性氮铁卟啉蛋白质硝化

Comparison of physiological responses to oxidative and heavy metal stress in seedlings of rice paddy, Oryza sativa L.

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Journal of Environmental Sciences 2000年第4期12卷 458-462页

作者： YU Guo\|ying, WANG Guo\|ping, HE chi\|quan (Lab for Wetland Process and Environment, Changchun Institute of Geography, The chinese Academy of Sciences, Changchun 130021,china E\|mail: yuguoying@***) 中科院长春地理所湿地环境开放实验室吉林长春 1 3 0 0 2

Physiological responses on the bases of activities of antioxidant enzymes: peroxidase, catalase, superoxide dismutase and glutathione reductase as well as estimation of total protein, lipid peroxidation and thiols in the form of protein, non\|protein, glutathione and phytochelatin measured in growing seedlings of paddy, Oryza sativa L., from day 2 to 8 were compared following treatment of seeds for 5h with oxidative agents, paraquat 5 × 10 -5 , 10 -4 , 10 -3 mol/L, H 2O 2 10 -3 , 5×10 -3 , 10 -2 mol/L, and CdCl 2 10 -5 , 10 -4 , 5×10 -3 mol/L. A significant induction of all antioxidant enzymes along with an increase in the levels of protein, lipid peroxidation and glutathione was noted in response to oxidative stress, CdCl 2 induced significant peroxidase and catalase activities but not superoxide dismutase. In a marked contrast from oxidative stress, CdCl 2 decreased glutathione reductase activity as well as glutathione levels but increased phytochelatin level. The different physiological responses thus underlined the crucial involvement of glutathione and phytochelatin in the oxidative and heavy metal\|linduced adaptive responses respectively.

关键词： adaptive response oxidative stress heavy metal antioxidant enzymes glutathione phytochelatin

3.5%NaCl腐蚀环境下2种航空铝合金材料疲劳性能试验研究

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工程力学 2017年第11期34卷 225-230页

作者：王池权熊峻江北京航空航天大学交通科学与工程学院北京100191

腐蚀环境下的疲劳性能是航空金属结构疲劳寿命设计的重要前提,为此,试验测定了2种航空铝合金材料(2E12-T3、7050-T7451)的光滑试样和缺口试样在干燥大气和3.5%Na Cl腐蚀环境下的疲劳性能,在试验数据的基础上进行性能对比,并对试样断口... 详细信息

腐蚀环境下的疲劳性能是航空金属结构疲劳寿命设计的重要前提,为此,试验测定了2种航空铝合金材料(2E12-T3、7050-T7451)的光滑试样和缺口试样在干燥大气和3.5%Na Cl腐蚀环境下的疲劳性能,在试验数据的基础上进行性能对比,并对试样断口进行扫描电镜(SEM)分析,研究了3.5%Na Cl腐蚀环境与载荷联合作用对腐蚀疲劳性能的影响机理,研究结果表明:3.5%Na Cl腐蚀环境对2种铝合金材料的疲劳性能均产生不利影响,且腐蚀与疲劳载荷的交互作用随着应力水平的降低而增强,疲劳性能下降更明显;与光滑试样相比,腐蚀环境对铝合金2E12-T3缺口试样疲劳性能的影响更大,但对铝合金7050-T7451缺口试样疲劳性能的影响却变小;在腐蚀环境下,裂纹尖端易发生电化学反应产生腐蚀产物和[H]离子,腐蚀产物的存在会阻碍裂纹闭合,同时,[H]离子导致裂纹尖端的氢脆效应,加快裂纹扩展,使疲劳性能降低。

关键词：疲劳腐蚀铝合金缺口 SEM

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蛋白质酪氨酸硝化的研究

化学进展 2006年第7期18卷 1019-1025页

作者：池泉黄开勋华中科技大学化学系武汉430074

蛋白质酪氨酸硝基化是一种重要的蛋白质翻译后修饰,与多种病症相关。经由过氧亚硝酸根(ONOO-)和NO2-/H2O2/血红素过氧化物酶体系是促使蛋白质硝化最主要的两种途径,其反应为自由基机理。本文对体内蛋白质硝基化的途径、机制及其生物学... 详细信息

蛋白质酪氨酸硝基化是一种重要的蛋白质翻译后修饰,与多种病症相关。经由过氧亚硝酸根(ONOO-)和NO2-/H2O2/血红素过氧化物酶体系是促使蛋白质硝化最主要的两种途径,其反应为自由基机理。本文对体内蛋白质硝基化的途径、机制及其生物学意义作了综述,指出蛋白质的硝化具有选择性,特定酪氨酸残基发生硝化能够改变蛋白质的结构和功能,影响其免疫应答和可能涉及的信号转导过程,从而具有重要的生物学意义。

关键词：酪氨酸硝化 3-硝基酪氨酸活性氮过氧亚硝酸根