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孔雀绿电极催化电位滴定法测定中草药中的锰

分析化学 2002年第5期30卷 568-570页

作者：董学芝李桂敏赵海兰魏林恒刘晓曼刘扬开封***届毕业生河南大学化学系河南大学化学系开封475001 郑州牧业高等专科学校工作

以氨三乙酸存在下锰催化高碘酸钾氧化孔雀绿的反应作指示反应 ,用孔雀绿选择性电极作指示电极 ,对于用催化电位滴定法测定微量锰进行了研究 ,选择了适宜的实验条件 ,并测定了中草药中的锰的含量 ,所得结果与原子吸收法一致。

关键词：催化滴定孔雀绿电极锰中草药

河南某市驾校地表灰尘多环芳烃组成、来源与健康风险

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环境科学 2017年第2期38卷 711-720页

作者：陈轶楠马建华段海静魏林恒河南大学资源与环境研究所开封475004 黄河文明传承与现代文明建设河南省协同创新中心开封475004

采集河南省某市29所驾校的地表灰尘样品,应用气相色谱-质谱联用仪(GC-MS)测定样品中16种优控PAHs含量,用终生致癌风险增量模型(ILCR)评价灰尘PAHs不同暴露情景下(情景1、2、3分别为驾校工作5 a、10 a和20 a)的健康风险,用比值法、成分... 详细信息

采集河南省某市29所驾校的地表灰尘样品,应用气相色谱-质谱联用仪(GC-MS)测定样品中16种优控PAHs含量,用终生致癌风险增量模型(ILCR)评价灰尘PAHs不同暴露情景下(情景1、2、3分别为驾校工作5 a、10 a和20 a)的健康风险,用比值法、成分谱法和主成分因子载荷法揭示PAHs来源.结果表明,驾校灰尘ΣPAHs含量在198.21~3 400.89μg·kg-1之间,平均908.72μg·kg-1.单体PAHs含量较高的是萘、菲、蒽、荧蒽,含量最低的是二苯并[a,h]蒽,低环PAHs占ΣPAHs的55.79%,高环占44.21%.3种情景下的平均健康风险为情景3(3.71×10-7)>情景2(1.85×10-7)>情景1(9.27×10-8),只有一个驾校(J11)在情景3存在潜在健康风险,其他情景下均无风险.皮肤接触灰尘是最主要的PAHs暴露途径,其占总风险的64.21%;其次是误食途径,占总风险的33.04%;吸入途径可忽略不计.驾校灰尘PAHs主要来源为化石燃料不完全燃烧源和混合源,农田区驾校灰尘PAHs的柴油/天然气动力车排放源、燃煤源和汽油车排放源贡献率分别为56.44%、26.55%和17.01%,工业区驾校混合源、汽油车和炼焦/燃煤排放源贡献率分别为76.26%、22.85%和0.89%,混合区驾校燃煤源、天然气/柴油动力车排放源和汽油车排放源的贡献率分别为45.57%、45.41%和9.02%.灰尘PAHs含量及健康风险与其周边环境、前期土地利用状况密切相关.

关键词：驾校地表灰尘 PAHs 健康风险来源组成

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催化滴定分析法的现状及进展

理化检验（化学分册） 2004年第7期40卷 423-426,429页

作者：魏林恒牛谦董学芝梁艳刘杨河南大学化学化工学院开封475001 三门峡西铁路医院

催化滴定是利用催化反应指示滴定终点的一种滴定分析方法,它兼具催化动力学分析法的高灵敏度和经典滴定分析法高准确度的特点,既适用于常量分析又适用于微量分析。此文就催化滴定在研究和应用方面的进展作出概述。

关键词：催化滴定进展终点指示综述

Hydrothermal Synthesis and Structure Characterization of a Novel 4,4′-Bipyridine Bridging Dumbbell-like Dimeric Pentamolybdate

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Chinese Journal of Structural Chemistry 2005年第9期24卷 991-996页

作者：王子梁魏林恒王敬平 School of Chemistry and Chemical Engineering Henan University Kaifeng 475001 China College of Environment and Planning Henan University Kaifeng 475001 China

A 4, 4＇-bipyridine bridging dumbbell-like dimeric pentamolybdate [4, 4＇-H2bipy]3[4,4＇-Hbipy]2[（Mo5O17）2（4,4＇-bipy）] has been synthesized by hydrothermal synthesis and characterized by elemental analysis, IR spectrum, UV spectrum, TG and X-ray crystallography. The title compound crystallizes in triclinic, space group PI with a=10.578（2）, b=11.047（2）, c=16.576（3） A°, a=79.86（3）, β=75.34（3）, γ=79.40（3）°, C60H58Mo10MoN12O34, Mr=2450.58, V=1824.8（6）A°^3, Z=1, Dr=2.230 g/cm^3, F（000） = 1194,μ= 1.757 mm^-1, the final R=0.0252 and wR=0.0559 for 5506 observed reflections with I〉2σ（I）. The structural analysis indicates that the title compound contains a novel polyanion [（Mo5O17）2（4,4＇-bipy）]^8-, in which two identical （Mo5O17）^4- anions are buttres sed by a 4,4＇-bipyridine molecule through Mo-N bond.

关键词： polyoxometalates hydrothermal synthesis molybdenum

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开封市土壤动物及其对土壤污染的响应

土壤学报 2007年第3期44卷 529-535页

作者：宋博马建华李剑魏林恒殷秀琴东北师范大学城市与环境学院长春130024 河南大学环境与规划学院河南开封475001

将开封市城市用地划分为农田、公共绿地、文教用地、居住用地和工业用地五种类型,作为五个采样区,采集了土壤和土壤动物样品,运用土壤理化分析和生态分析的方法,研究了城市生态系统土壤中动物类群特征,以及土壤动物对土壤污染的响应。... 详细信息

将开封市城市用地划分为农田、公共绿地、文教用地、居住用地和工业用地五种类型,作为五个采样区,采集了土壤和土壤动物样品,运用土壤理化分析和生态分析的方法,研究了城市生态系统土壤中动物类群特征,以及土壤动物对土壤污染的响应。结果发现不同土地利用类型中土壤动物的组成不同,农田、城市绿地和文教用地中土壤动物的优势类群均为弹尾目、前气门亚目和线虫;居住用地为弹尾目和前气门亚目;工业用地为弹尾目和线虫。土壤动物的数量与pH值具有良好的相关性。土壤动物的多样性指数与土壤污染程度具有显著的负相关性,可以利用多样性指数指示土壤综合污染程度。

关键词：土壤动物城市土壤土壤环境开封市

Synthesis, Structure and Theoretical Calculation of Imidazolium 3,5-Dinitrobenzoate

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Chinese Journal of Structural Chemistry 2007年第12期26卷 1423-1428页

作者：王子梁魏林恒金邻豫王敬平 Institute of Molecule and Crystal Engineering College of Chemistry and Chemical Engineering Henan University College of Environment and Planning Henan University

The title adduct imidazolium 3,5-dinitrobenzoate has been synthesized in aqueous solution and characterized by elemental analyses, IR spectrum and X-ray crystallography. The title compound belongs to monoclinic, space group P21/n with a = 7.5540（9）, b = 21.333（2）, c = 7.7823（9）A, β = 102.741（2）^o, C10H8N4O6, Mr = 280.20, V= 1223.3（2）A^3, Z = 4, Dc = 1.521 g/cm^3, F（000） = 576, p = 0.129 mm^-1, the final R = 0.0433 and wR = 0.1092 for 2001 observed reflections with I 〉 2a（I）. The structural analysis indicates the component ions are linked by N-H...O hydrogen bonds into an infinite one-dimensional C2^2 （8） chain parallel to the [1 0 -1] direction. Moreover, the theoretical investigations of the title compound with HF/6-31G（d） method were performed, and its stability, frontier molecular orbital composition and Mulliken charge distribution were also discussed.

关键词： imidazole 3,5-dinitrobenzoic acid crystal structure hydrogen bonds theoretical calculation mulliken

Crystal Structure, Hirshfeld Surface Analysis and Quantum Mechanical Study of a Cocrystal Based on 1,3-Di（4-pyridyl）propane and 3-（（4~′-Carboxybenzyl）oxy） Benzoic Acid

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Chinese Journal of Structural Chemistry 2013年第9期32卷 1367-1373页

作者：魏林恒王子梁李明雪 College of Environment and Planning Henan University College of Chemistry and Chemical Engineering Henan University

A cocrystal based on 1,3-di（4-pyridyl）propane and 3-（（4′-carboxybenzyl）oxy）benzoic acid,C13H14N2·C15H12O5,has been synthesized and characterized by single-crystal X-ray *** compound crystallizes in monoclinic,space group P21 /c with a = 11.639（4）,b = 9.808（3）,c = 20.854（6）,β = 91.242（7）°,V = 2380.0（13）3,C28H26N2O5,Mr = 470.51,Dc = 1.313 g/cm3,μ（MoKα） = 0.091 mm-1,F（000） = 992,Z = 4,the final R = 0.0677 and wR = 0.1477 for 4175 observed reflections（I 2σ（I））.Intermolecular N H···O hydrogen bonds link two kinds of components into a one-dimensional chain in [10-1] direction and adjacent chains are further arranged into a two-dimensional network by π···π and C H···π *** of intermolecular interactions and crystal packing via Hirshfeld surface analysis reveals that the close contacts are mainly focused on weak *** theoretical investigations with HF/6-31G（d） method were performed,and its stability,frontier molecular orbital composition and Mulliken charge distribution were also discussed.

关键词： crystal structure quantum Hirshfeld surface hydrogen bond cocrystal

Structural Investigation,Quantum Mechanical Study and Hirshfeld Surface Analysis of One Novel Adduct Based on Aminopyridinium and Biphenyl-2,4′-dicarboxylate

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Chinese Journal of Structural Chemistry 2013年第5期32卷 756-762页

作者：王子梁魏林恒李明雪 College of Chemistry and Chemical Engineering Henan University College of Environment and Planning Henan University

One novel adduct based on aminopyridinium and biphenyl-2,4′-dicarboxylate, C5H7N2＋·C14H9O4-, has been synthesized and characterized by X-ray structural study. The compound crystallizes in trigonal, space group P32 with a = 9.2886（16）, b = 9.2886（16）, c = 16.746（6） , γ = 120°, V = 1251.2（5） 3, C19H16N2O4, Mr = 336.34, Dc = 1.339 g/cm3, μ（MoKα） = 0.095 mm-1, F（000） = 528, Z = 3, the final R = 0.0438 and wR = 0.1119 for 3097 observed reflections （Ⅰ 〉 2σ（Ⅰ））. Its electronic structure was calculated at the RHF/6-31G（d） level and a detailed analysis of intermolecular interactions was used by Hirshfeld surface and fingerprint plot. Intermolecular N-H…O hydrogen bonds link two components generating R22（8） rings which are linked into three one-dimensional chains in the [100], [010] and [110] directions, and these chains are finally arranged into a three-dimensional framework by hydrogen bonds. Investigation of intermolecular interactions via Hirshfeld surface analysis reveals that the close contacts are mainly associated with the classical hydrogen bonding interactions. The HOMO-LUMO energy gap of the compound indicates a higher kinetic stability.

关键词： crystal structure quantum Hirshfeld surface fingerprint plot hydrogen bond

Syntheses,Crystal Structures and Theoretical Calculation of Two Transition Metal Dinuclear Complexes

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Chinese Journal of Structural Chemistry 2008年第11期27卷 1327-1332页

作者：王子梁魏林恒李明雪王敬平 Institute of Molecule and Crystal Engineering College of Chemistry and Chemical EngineeringHenan University College of Environment and Planning Henan University

Two transition metal dinuclear complexes of [Mn2（OOCC6H4SSC6H4COO）- （Phen）2（H20）]n 1 and [CuE（OOCC6H4S）2（Phen）2] 2 were hydrothermally synthesized by the reaction of equivalent metal dichloride with 2,2＇-dithiobis（benzoic acid）（HE-DTBB）. Structure analysis indicates that each Mn2＋ ion in I is coordinated by one chelate phen ligand, one bridging water molecule and three DTBB ligands forming Mn2＋ dinuclear units which are further linked into one-dimensional chain by DTBB ligand. Under similar reaction conditions, the 2,2＇-dithio- his（benzoic acid） ligand undergoes thiol reduction to form 2-mercaptobenzoic （H-2-MBA） in 2 where two Cu2＋ ions are coordinated by phen and MBA ligands only constructing a dinuclear unit.

关键词： coordination polymers crystal structure dinuclear theoretical investigation