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红外光谱对碱土金属二元羧酸盐结构的研究 被引量:30
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作者 李小俊 胡克良 +1 位作者 黄允兰 周贵恩 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2002年第3期392-395,共4页
研究了三十种二元羧酸金属盐的红外光谱 ,讨论了金属离子和二元酸的种类对二元酸盐配位结构的影响 ,发现Mg盐、Ba盐、Sr盐为螯合配位 ,Ca盐、Zn盐中同时存在螯合配位和桥式配位。二元酸的种类对羧酸盐配位结构没有影响。对羧酸盐在常温... 研究了三十种二元羧酸金属盐的红外光谱 ,讨论了金属离子和二元酸的种类对二元酸盐配位结构的影响 ,发现Mg盐、Ba盐、Sr盐为螯合配位 ,Ca盐、Zn盐中同时存在螯合配位和桥式配位。二元酸的种类对羧酸盐配位结构没有影响。对羧酸盐在常温和熔融后的配位方式和结构上的差异的研究结果表明 ,Mg盐、Ca盐与Sr盐。 展开更多
关键词 红外光谱 碱土金属 结构 二元羧酸盐 配位方式
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硫脲衍生物受体的阴离子识别研究 被引量:15
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作者 梅明华 吴世康 《化学学报》 SCIE CAS CSCD 北大核心 2001年第7期1112-1115,共4页
设计、合成了双支链结构的萘基硫脲衍生物.利用吸收光谱和1H NMB表征了该化合物与不同链长的二羧酸盐阴离子的相互作用.实验结果表明,阴离子与主体化合物间通过多重氢键形成配合物、导致萘基硫脲衍生物光谱发生变化.测定了配合物的稳定... 设计、合成了双支链结构的萘基硫脲衍生物.利用吸收光谱和1H NMB表征了该化合物与不同链长的二羧酸盐阴离子的相互作用.实验结果表明,阴离子与主体化合物间通过多重氢键形成配合物、导致萘基硫脲衍生物光谱发生变化.测定了配合物的稳定性,发现衍生物对二羧酸盐阴离子的选择性取决于二羧酸阴离子链的长短.并根据实验结果提出了可能的配合物结合方式. 展开更多
关键词 硫脲 二羧酸盐 阴离子识别 衍生物 人工模拟受体 超分子化学
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新型PVC热稳定剂——二元羧酸盐的研究 被引量:6
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作者 刘艳斌 刘伟区 +1 位作者 石磊 侯孟华 《中国塑料》 CAS CSCD 北大核心 2006年第8期75-78,共4页
通过碱中和法制备了已二酸钙、癸二酸钙、癸二酸锌和复分解反应法制备了二聚酸钙,并通过红外检测和元素分析证明了二元羧酸盐的结构,采用刚果红法与热烘法研究了二元羧酸盐对PVC的热稳定作用。结果表明,二元羧酸盐都有不同程度的热稳定... 通过碱中和法制备了已二酸钙、癸二酸钙、癸二酸锌和复分解反应法制备了二聚酸钙,并通过红外检测和元素分析证明了二元羧酸盐的结构,采用刚果红法与热烘法研究了二元羧酸盐对PVC的热稳定作用。结果表明,二元羧酸盐都有不同程度的热稳定性。由于二元羧酸锌存在严重的“锌烧”缺陷,刚果红试纸变色时间较与其有相同羧酸基的钙盐短,如癸二酸钙为37.0min,癸二酸锌为8.0min。几种二元羧酸钙中癸二酸钙对PVC的热稳定效果最好,当其含量达到1%时,对PVC已具有较好的热稳定性效果。 展开更多
关键词 聚氯乙烯 二元羧酸盐 热稳定性
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Organic Carboxylate Ligand Tuned Topological Variations in Three Zn(Ⅱ)Coordination Polymers:Syntheses,Crystal Structures and Photoluminescent Properties 被引量:4
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作者 柳长庆 杨锦霞 +2 位作者 张鑫 覃业燕 姚元根 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第9期1470-1478,共9页
Three new Zn(Ⅱ) coordination polymers, namely [Zn2(suc)2(bib)2]n·nH2 O(1), [Zn(glu)(bib)]n·4 nH2 O(2), and [Zn(adp)(bib)]n(3)(bib = 1,4-bis(N-imidazolyl)butane, H2 suc = succinic acid... Three new Zn(Ⅱ) coordination polymers, namely [Zn2(suc)2(bib)2]n·nH2 O(1), [Zn(glu)(bib)]n·4 nH2 O(2), and [Zn(adp)(bib)]n(3)(bib = 1,4-bis(N-imidazolyl)butane, H2 suc = succinic acid, H2 glu = glutaric acid, H2 adp = adipic acid) have been hydrothermally synthesized and structurally characterized. Compound 1 features a 3D framework with 4-connected hxg-d topological network, compound 2 is comprised of 2D 44-sql-type sheets, and the adjacent 2D sheets are further packed into a 3D supramolecular architecture via intermolecular hydrogenbonding interactions, and compound 3 is a 3D framework with 4-fold interpenetrating dia topology. The structural comparison of these three compounds demonstrates that the topological variations can be well controlled by employing aliphatic dicarboxylate ligands with different spacer lengths. Moreover, the thermal stabilities and photoluminescent properties of them were also studied in detail. 展开更多
关键词 zinc(Ⅱ) compound aliphatic dicarboxylate ligands hydrothermal reaction meso-helix hydrogen bond photoluminescence
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Protective Effect of Dimethyl-4,4'-Dimethoxy-5,6,5',6'-Dimethylene Dioxybiphenyl-2,2'-Dicarboxylate (DDB) against Carcinogen-Induced Rat Liver Nuclear DNA Damage 被引量:4
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作者 QlNG WEIGUO1 AND LIU GENGTAODepartment of Pharmacology, Institute of Materia Medico, Chinese Academy of Medical Sciences, 1 Xian Nong Tan Street, Beijing 100050,ChinaBeijing Institute for Cancer Research, Da-Hong-Luo-Chang Street, West District, Beijing, 100034 China.To whom correspondence should be addressed. 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1992年第3期201-207,共7页
The protective effect of DDB against carcinogen-induced DNA damage was examined in the present investigation. Preincubation of rat liver nuclei with DDB (1 mmol.L-1) resulted in 60% inhibition of binding of 3H-benzo (... The protective effect of DDB against carcinogen-induced DNA damage was examined in the present investigation. Preincubation of rat liver nuclei with DDB (1 mmol.L-1) resulted in 60% inhibition of binding of 3H-benzo (a) pyrene to nuclear DNA. Unscheduled DNA synthesis (UDS) induced by aflatoxin BI (10^(-7) mol.L-1) in freshly isolated rat hepatocytes was also inhibited by DDB (10^(-6)-10^(-3)mol.L-1). Oral administration of DDB at 200 mg.kg-1 once daily for 3 d induced a significant increase of liver cytosol glutathione-S-transferase and microsomal UDPG-transferase activity in mice. These results indicate that DDB is able to directly or indirectly antagonize certain carcinogen-induced DNA damages. 展开更多
关键词 DDB Dimethylene Dioxybiphenyl-2 2 Dimethoxy-5 6 5 dicarboxylate Protective Effect of Dimethyl-4 4 against Carcinogen-Induced Rat Liver Nuclear DNA Damage DNA
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发光型主体分子胍基芘识别二羧酸根阴离子 被引量:3
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作者 刘磊 童爱军 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2002年第2期273-277,共5页
在质子性溶剂甲醇中 ,发光型主体分子胍基芘通过氢键与二羧酸根阴离子结合 ,自组装形成 2∶1的主客体超分子复合物。本文采用前表面反射荧光检测 ,通过跟踪主体分子结合客体前后芘的激基二聚体与单体荧光强度比值的变化 ,研究了胍基芘... 在质子性溶剂甲醇中 ,发光型主体分子胍基芘通过氢键与二羧酸根阴离子结合 ,自组装形成 2∶1的主客体超分子复合物。本文采用前表面反射荧光检测 ,通过跟踪主体分子结合客体前后芘的激基二聚体与单体荧光强度比值的变化 ,研究了胍基芘对不同酸根数目、不同取代位置的苯取代羧酸盐、磺酸盐、长链二羧酸盐以及双羧基氨基酸的识别能力和识别选择性。结果表明 ,胍基芘对二羧酸根阴离子的识别能力与客体分子中两个羧基间的距离、分子的平面构型以及取代基的种类密切相关。 1,2 ,4,5 苯四甲酸根的识别效果远远好于其他二羧酸根阴离子。 展开更多
关键词 发光型主体分子 胍基芘 二羧酸根阴离子 分子识别 激基二聚体 前表面反射荧光 分子自组装 超分子 氢键
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Preparations and characterizations of two MOFs constructed with hydroxylphenyl imidazole dicarboxylate 被引量:2
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作者 Ji-Feng Wang Bing-Bing Shi Gang Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2015年第9期1059-1064,共6页
Using the hydrothermal reactions of Mn(Ⅱ) and Ba(Ⅱ) salts with 2-(3-hydroxylphenyl)-1H-imidazole-4,5-dicarboxylic acid(m-OHPhH3IDC),two novel metal-organic frameworks,namely,{[Mn(mOHPhHIDC)(H2O)]2H2On(1... Using the hydrothermal reactions of Mn(Ⅱ) and Ba(Ⅱ) salts with 2-(3-hydroxylphenyl)-1H-imidazole-4,5-dicarboxylic acid(m-OHPhH3IDC),two novel metal-organic frameworks,namely,{[Mn(mOHPhHIDC)(H2O)]2H2On(1) and {[Ba(m-OHPhH2IDC)2(H2O)3]-2H2O)n,(2) have been synthesized and structurally characterized by single-crystal X-ray crystallography,elemental analyses,and IR spectroscopy.Complex 1 features a novel non-interpenetrated three-dimensional(3,4)-connected network with one-dimensional open channels.Complex 2 exhibits a two-dimensional layered structure with rhombic grids.The role of the central metals in the formation of final architectures has been discussed.Furthermore,luminescent and thermal properties of the two complexes have been studied. 展开更多
关键词 Imidazole dicarboxylate Metal-organic frameworks Manganese Barium Property
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Crystal Structures and Photoluminescent Properties of Two Cd^(2+) Coordination Polymers Constructed from an 8-Hydroxyquinolinate Ligand 被引量:2
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作者 金锁 顾清韵 +2 位作者 陈静 王杨志 袁国赞 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第6期929-938,共10页
In order to perform a study on the structural modulation in the Cd(Ⅱ)-L architecture(HL =(E)-2-[2-(3-pyridyl)ethenyl]-8-hydroxyquinoline), two different dicarboxylic acids, namely, 2-aminoterephthalic acid(H... In order to perform a study on the structural modulation in the Cd(Ⅱ)-L architecture(HL =(E)-2-[2-(3-pyridyl)ethenyl]-8-hydroxyquinoline), two different dicarboxylic acids, namely, 2-aminoterephthalic acid(H_2ATA) and 4,4¢-biphenyldicarboxylic acid(H_2BPDC), are employed as the secondary auxiliary ligands. Two new complexes [Cd_2L_2(ATA)](1) and [Cd_2L_2(BPDC)·2MeO H· 4H_2O](2) with distinct 3D frameworks were obtained. In complex 1, ligands ATA bridge the 1D Cd(Ⅱ)-L infinite chains into a 3D polymeric coordination network. Complex 2 is a 3D porous framework, in which adjacent 2D Cd(Ⅱ)-L coordination layers were linked together by the coor- dinated BPDC ligands. The variant structures of two complexes indicate that the skeleton of dicarboxylate anions plays a great role in the assembly of such different frameworks. In addition, the photoluminescent properties(fluorescent emission, lifetime, and quantum yield) of polymers 1 and 2 were also investigated in the solid state. 展开更多
关键词 coordination polymer dicarboxylate crystal structure photoluminescence
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Measurement and Correlation for Solubility of Dimethyl-2,6-naphthalene Dicarboxylate in Organic Solvents 被引量:4
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作者 夏清 马沛生 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第2期215-220,共6页
Solubility of dimethyl-2,6-naphthalene dicarboxylate in acetic acid, N,N-dimethylfonnamide, N,N-dimethyl acetamide, dimethyl sulphoxide, and N-methyl-2-ketopyrrolidine were determined using a dynamic method. The measu... Solubility of dimethyl-2,6-naphthalene dicarboxylate in acetic acid, N,N-dimethylfonnamide, N,N-dimethyl acetamide, dimethyl sulphoxide, and N-methyl-2-ketopyrrolidine were determined using a dynamic method. The measured systems were correlated by UNIFAC group contribution method. A new main group (aromatic ester, ACCOO) was defined to express the activity coefficients of the aromatic ester. New interaction parameters of the ACCOO group were expressed as the first-order function of temperature and were determined from the experimental data. The calculated results for the new interaction parameters were satisfactory. The measured systems were also correlated with the Wilson and 2-h models, and the results were compared with those of the UNIFAC model. 展开更多
关键词 solid-liquid equilibrium SOLUBILITY dimethyl-2 6-naphthalene dicarboxylate UNIFAC group contribution method activity coefficient
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有机锡农药的合成及其微胶囊的制备
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作者 钟桂云 《广东化工》 CAS 2023年第4期32-33,4,共3页
有机锡化合物作为除草剂、杀螨剂、杀菌剂等,广泛地在农业生产中应用。本文在前期研究的基础上,以具有良好杀菌活性的丁基和环己基混合烃基有机锡化合物作为母体,在有机胺存在下与二元羧酸反应合成离子型有机锡二元羧酸酯化合物,通过核... 有机锡化合物作为除草剂、杀螨剂、杀菌剂等,广泛地在农业生产中应用。本文在前期研究的基础上,以具有良好杀菌活性的丁基和环己基混合烃基有机锡化合物作为母体,在有机胺存在下与二元羧酸反应合成离子型有机锡二元羧酸酯化合物,通过核磁共振、红外、元素分析对产物进行结构鉴定,并测定了其杀菌活性,筛选出高活性的有机锡产物制成有机锡杀菌剂微胶囊,为有机锡农药的应用和农业生产提供帮助。 展开更多
关键词 微胶囊 有机锡 二元羧酸酯 杀菌活性 农药
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Three New Complexes Based on the Flexible Zwitterionic Dicarboxylate Ligand: Synthesis, Structures, and Properties 被引量:1
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作者 Qing Wang Bao Mu +3 位作者 Dandan Yang Lei Lv Changxia Li Rudan Huang 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2016年第2期225-232,共8页
Three new complexes have been prepared based on the transition metals and zwitterionic dicarboxylate ligand 1,1'-(1,4-phenylene-bis(methylene))-bis(pyridine-3-carboxylic acid) (L), whose formulas are {[Cd4(... Three new complexes have been prepared based on the transition metals and zwitterionic dicarboxylate ligand 1,1'-(1,4-phenylene-bis(methylene))-bis(pyridine-3-carboxylic acid) (L), whose formulas are {[Cd4(L)(SO4)]· (C1)6}n (1), [Zn(L)C12], (2), and [Co(L)C12], (3), respectively. Complexes 1-3 have been characterized by elemental analyses, IR spectroscopy, XRD, thermal analyses and single crystal X-ray (powder) diffraction. 1 crystallizes in monoclinic space group C2/m, displaying a 2-D layer structure with three unique Cd^2+ centers. 2 and 3 are iso- morphic structures with the orthorhombic Cmca space group. They exhibit a 1-D zigzag chain, which can be linked to generate a 2-D layer via hydrogen bonding interactions (C--H'"O). Moreover, electrochemical behavior reveals that the redox reaction of 3-CPE is a surface-controlled reaction. And the luminescent properties of the title comlexes have been investigated at room temperature. 展开更多
关键词 zwitterionic dicarboxylate ligand tetranuclear complex electrochemial property luminescent property
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Expression of EGFP/SDCT1 fusion protein,subcellular localization signal analysis,tissue distribution and electrophysiological function study 被引量:1
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作者 BAI Xueyuan CHEN Xiangmei +4 位作者 FEN Zhe WU Di HOU Kai CHENG Genyang PENG Lixia 《Science China(Life Sciences)》 SCIE CAS 2004年第6期530-539,共10页
Full-length cDNA gene of sodium-dependent dicarboxylate co-transporter protein 1 (SDCT1) is cloned from normal human kidney tissue and inserted into EGFP (enhanced green fluorescent protein) expression vector along wi... Full-length cDNA gene of sodium-dependent dicarboxylate co-transporter protein 1 (SDCT1) is cloned from normal human kidney tissue and inserted into EGFP (enhanced green fluorescent protein) expression vector along with N-terminal and C-terminal truncated SDCT1 genes, so to construct the eukaryotic expression vectors of EGFP/SDCT1 fusion proteins, which are transfected into human renal tubular epithelial cells (HKC). Subcellular localizations of these fusion proteins are observed by laser confocal microscope to determine the localization signal of the SDCT1 protein. Duplex PCR analysis validates that the fusion protein genes have been in- tegrated into the genome of HKC. Western blot indicates that the fusion proteins have been ex- pressed in HKC. Confocal microscopy analysis shows that human SDCT1 predominantly locates on the plasma membrane, which is consistent with the results predicted by bioinformatics ap- proach; in HKC transfected with N-terminal truncated SDCT1 gene, the green fluorescence is mainly distributed on the plasma membrane; in HKC transfected with C-terminal truncated SDCT1 gene, the green fluorescence is mainly distributed in the cytoplasm. EGFP/SDCT1 mRNAs obtained by in vitro transcription are microinjected into Xenopus laevis oocytes for ex- pression and the trans-membrane currents are measured by using two-microelectrode volt- age-clamp technique. Na+ inward currents are present on cellular membrane of the injected oo- cytes. Immunohistochemical staining shows that human SDCT1 proteins are expressed on lu- men membrane of the renal proximal tubule, but are negative in distal tubule, collecting duct, renal interstitium and glomerulus. The above-mentioned studies suggest that human SDCT1 protein is located on the lumen membrane of the renal proximal tubule, the C-terminal sequence of the SDCT1 is required for delivery and targeting localization, and the plasma membrane lo- calization signal of the SDCT1 protein maybe locate in the C-terminal sequence. 展开更多
关键词 dicarboxylate co-transporter tricarboxylic acid cycle renal tubule subcellular localization.
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Therapeutic Effect of Dimethyl Dimethoxy Biphenyl Dicarboxylate on Collagen-Induced Arthritis in Rats 被引量:1
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作者 Roba M Talaat Amira S Abo-EI-Atta +1 位作者 Sabah M Farou Karima I EI-Dosoky 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2015年第11期846-854,共9页
Objective: To study the effect of oral administration of dimethyl dimethoxy biphenyl dicarboxylate (DDB) on adjusting angiogeneic/inflammatory mediators and ameliorating the pathology of bones in rats with collagen... Objective: To study the effect of oral administration of dimethyl dimethoxy biphenyl dicarboxylate (DDB) on adjusting angiogeneic/inflammatory mediators and ameliorating the pathology of bones in rats with collagen-induced arthritis (CIA). Methods: Wistar rat model of CIA was set up using bovine collagen type H. Fifty rats were divided into five groups randomly: normal, CIA model, DDB treatment, methotrexate (MTX) treatment, and combined DDB+MTX treatment. Ankle joints of rats were imaged with digital X-ray machine to show the destruction of joints. Fore and hind paw and knee joints were removed above the ankle joint then processed for haematoxylin and eosin staining. Plasma levels of vascular endothelial growth factor (VEGF), platelet derived growth factor, interleukin-8 (IL-8), IL-4, tumor necrosis factor α (TNF-α), and cyclooxygenase-2 (COX-2) were quantified by enzyme-linked immunosorbent assay. Nitric oxide levels were detected by Griess reagent. Results: Compared with the CIA model group, a remarkable reduction in various angiogenic (VEGF and IL-8) and inflammatory mediators (TNF-α, IL-4 and COX-2) after treatment with DDB either alone or combined with MTX (P〈0.05 or P〈0.01). Histopathological and X-ray findings were confirmatory to the observed DDB anti-arthritic effect. The DDB-treated group showed amelioration in signs of arthritis which appeared essentially similar to normal. Conclusion: Our data shed light on the therapeutic efficacy of DDB in experimental rheumatoid arthritis (RA) compared with a choice drug (MTX) and it may be offered as a second-line drug in the treatment of RA. 展开更多
关键词 rheumatoid arthritis collagen-induced arthritis dimethyl dimethoxy biphenyl dicarboxylate ANGIOGENESIS INFLAMMATION
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A viologen-urea-based anion receptor:Colorimetric sensing of dicarboxylate anions 被引量:1
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作者 Zhi-Yun Dong Da-Wei Zhang +2 位作者 Xiao-Zhi Jiang Hui Li Guo-Hua Gao 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第8期688-690,共3页
Compound 1 bearing urea and viologen groups has been designed and synthesized.It could be used as a colorimetric receptor for dicarboxylate anions due to the significant color changes of the solution upon the addition... Compound 1 bearing urea and viologen groups has been designed and synthesized.It could be used as a colorimetric receptor for dicarboxylate anions due to the significant color changes of the solution upon the addition of dicarboxylates.More importantly,the color changes were related to the chain lengths of the dicarboxylates tested.UV-vis,'H NMR and HRMS studies demonstrated that receptor 1 utilized hydrogen bonds and electrostatic interactions to form 1:1 stoichiometry complexes with these anions.In addition,the generation of cation radical 1' during the complexation process was also detected by EPR. 展开更多
关键词 Colorimetric receptor Urea Viologen dicarboxylate
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Syntheses and Characterizations of Two Manganese(Ⅱ)Coordination Polymers Containing Three-dimensional Interpenetrating Networks Constructed by Mixed Ligands 被引量:1
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作者 郝少云 郝增川 +1 位作者 刘永光 董桂英 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第1期118-126,共9页
Two new three-dimensional coordination polymers, namely [Mn(L)(bpdc)]n(1), [Mn(L)0.5(ndc)]n(2)(L = 1,4-bis(2-methylbenzimidazole)butane, H2 bpdc = 4,4'-biphenyldicarboxylic acid, H2 ndc = 2,6-naphthale... Two new three-dimensional coordination polymers, namely [Mn(L)(bpdc)]n(1), [Mn(L)0.5(ndc)]n(2)(L = 1,4-bis(2-methylbenzimidazole)butane, H2 bpdc = 4,4'-biphenyldicarboxylic acid, H2 ndc = 2,6-naphthalenedicarboxylic acid) have been successfully synthesized under hydrothermal conditions. Two complexes were characterized by physico-chemical, spectroscopic methods and single-crystal X-ray diffraction. Complex 1 shows a 3D → 3D 5-fold interpenetrated network with a 4-connected uninodal dia topology. Complex 2 possesses a 3D → 3D 3-fold interpenetrating architecture with a binodal(4,5)-connected xah topology. The fluorescence and thermal properties of the title complexes were discussed. 展开更多
关键词 bis(benzimidazole) catalytic property dicarboxylate fluorescence property manganese(Ⅱ)
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The Synthesis of α-DDB, β-DDB and Theoretical Study with AM1
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作者 Rui Yun GUO Jun Biao CHANG +2 位作者 Rong Feng CHEN Jing Xi XIE Da Yu YAN 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第6期491-494,共4页
The present paper reports the synthesis of two analogs of Schzandrin C (-DDB, (-DDB with the gallic acid as the starting material. The key step is the synthesis of monomer of (-DDB and (-DDB for coupling. (-DDB, (-DD... The present paper reports the synthesis of two analogs of Schzandrin C (-DDB, (-DDB with the gallic acid as the starting material. The key step is the synthesis of monomer of (-DDB and (-DDB for coupling. (-DDB, (-DDB have different yields in Ullmann coupling reaction under the same condition. The yield of (-DDB is little lower than that of (-DDB. The AM1 calculation demonstrates that ΔH of the Ullmann coupling reaction of (-DDB and (-DDB are different. The former is -175.76966KJ/mol and the later is -203.21246KJ/mol. This is in agreement with the fact that (-DDB has higher yield than (-DDB. 展开更多
关键词 Analogs of Schzandrin C BIPHENYL dimenthoxy dicarboxylate biphenyl AM1 calculation
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以9,10-双(咪唑基)蒽为配体的锌配合物的合成、晶体结构和荧光性质 被引量:3
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作者 施梅 喻敏 刘光祥 《无机化学学报》 SCIE CAS CSCD 北大核心 2020年第12期2367-2376,共10页
以9,10-双(咪唑基)蒽(DIA)和硝酸锌为原料,分别与对苯二甲酸(H2bdc)、二苯甲酮-4,4'-二羧酸(H2cdc)、反式-1,4-环己二甲酸(H2chdc)在溶剂热条件下反应,得到3个结构不同的配位聚合物[Zn2(DIA)(bdc)2]n(1)、{[Zn(DIA)(cdc)]·H2O}... 以9,10-双(咪唑基)蒽(DIA)和硝酸锌为原料,分别与对苯二甲酸(H2bdc)、二苯甲酮-4,4'-二羧酸(H2cdc)、反式-1,4-环己二甲酸(H2chdc)在溶剂热条件下反应,得到3个结构不同的配位聚合物[Zn2(DIA)(bdc)2]n(1)、{[Zn(DIA)(cdc)]·H2O}n(2)和[Zn(DIA)(chdc)]n(3)。对它们进行了X射线单晶衍射分析、元素分析、红外光谱分析和热重分析。单晶结构分析显示,配合物1是第一例拥有三维(4,7)-连接的{3^2.4.5^2.6}{3^2.4^8.5^4.6^^5.72}2拓扑结构;配合物2具有二维格子状结构,层与层之间通过O-H…O和π…π弱相互作用形成三维超分子结构;而配合物3具有二维两重贯穿的层状结构。结果说明有机羧酸的长度和刚柔性在配合物组装过程中起着非常重要的作用。此外,在室温下对3个配合物进行了荧光性质分析。 展开更多
关键词 锌配合物 双咪唑配体 羧酸配体 晶体结构 荧光性质
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Protective Effects of Dimethyl-4,4'-Dimethoxy-5,6,5',6'-Dimethylene Dioxybiphenyl-2,2'-Dicarboxylate on Damages of Isolated Rat Hepatocytes Induced by Carbon Tetrachloride and D-galactosamine 被引量:2
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作者 FU TIEBO AND LIU GENGTAODepartment of Pharmacology, Institute of Materia Medica, Chinese Academy of Medical Sciences, 1 Xian Nong Tan Street, Beijing 100050,ChinaFox Chase Cancer Center. 7701 Burholme Avenue. Philadelphia, Pennsylvania 19111, USA.To whom correspondence should be addressed. 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1992年第3期185-194,共10页
The protective effect of biphenyl dimethyl dicarboxylate (DDB) on chemically induced damages was studied in isolated suspended rat hepatocytes. The experimental results showed that DDB (200μg/106 cells) efficiently p... The protective effect of biphenyl dimethyl dicarboxylate (DDB) on chemically induced damages was studied in isolated suspended rat hepatocytes. The experimental results showed that DDB (200μg/106 cells) efficiently protected the hepatocytes against carbon tetrachloride (CC14 10 mrnol.L-1) and D-galactosamine (1 mmol.L-1) induced damages. Membranal lipid peroxidation (malondialdehyde, MDA formation) and glutamic pyruvic transaminase (GPT) release from the hepatocytes were markedly decreased. The damage of the cell surfaces of the hepatocytes were also reduced as seen under a scanning electron microscope (SEM). Pretreatment with DDB (300 mg-kg-1) orally ameliorated the reduction of liver glycogen and blood glucose caused by ip injection of D-galactosamine (800 mg-kg-1) in mice. When normal rats were given DDB 300 mg-kg-1 once daily for 10 d, the free ribosomal protein and RNA in the liver increased significantly. These results indicate that DDB is of beneficial effects on both damaged and normal hepatocytes. 展开更多
关键词 Protective Effects of Dimethyl-4 4 Dimethylene Dioxybiphenyl-2 2 dicarboxylate on Damages of Isolated Rat Hepatocytes Induced by Carbon Tetrachloride and D-galactosamine Dimethoxy-5 6 5
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二元酸盐聚丙烯β晶型成核剂的制备及性能 被引量:3
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作者 吕志平 徐美玲 +1 位作者 万兆荣 王卫星 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2011年第12期110-113,共4页
利用邻苯二甲酸酐,甘氨酸和氢氧化钙制备了新型结构成核剂——N-甘氨酸基苯甲酰氨酸钙(PGCa)。利用TGA考察了其热稳定性,采用X射线衍射分析(XRD)和偏光显微镜(PLM)对其改性聚丙烯的结晶形态进行了表征,用差示扫描量热法(DSC)研究了其结... 利用邻苯二甲酸酐,甘氨酸和氢氧化钙制备了新型结构成核剂——N-甘氨酸基苯甲酰氨酸钙(PGCa)。利用TGA考察了其热稳定性,采用X射线衍射分析(XRD)和偏光显微镜(PLM)对其改性聚丙烯的结晶形态进行了表征,用差示扫描量热法(DSC)研究了其结晶行为,并测试了其力学性能。结果表明,PGCa是一种有效的β晶型聚丙烯成核剂。当PGCa质量分数为0.15%时,β晶型的相对含量可达74.2%,抗冲击强度由纯PP的12.07 kJ/m2提高到38.13 kJ/m2,拉伸强度和弯曲强度略有降低。 展开更多
关键词 聚丙烯 二元羧酸盐 Β晶型成核剂 性能
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Synthesis and Crystal Structure of a Novel Monomeric Di butyltin Dicarboxylate: nBu 2Sn O 2CCH 2CH(4 ClC 6H 4)Ge(OCH 2CH 2) 3N 2·H 2O
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《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1999年第2期9-13,共5页
nBu 2Sn O 2CCH 2CH(4 ClC 6H 4)Ge(OCH 2CH 2) 3N 2·H 2O( M r =1053.66) is an air stable compound which crystallizes in the monoclinic space group C2/c with a=21.182(5), b=12.174(3), c=17.108... nBu 2Sn O 2CCH 2CH(4 ClC 6H 4)Ge(OCH 2CH 2) 3N 2·H 2O( M r =1053.66) is an air stable compound which crystallizes in the monoclinic space group C2/c with a=21.182(5), b=12.174(3), c=17.108(4) , β=99.59(2)°, V=4350(3) 3, Z=4, F(000)=2104, μ =2.104 mm -1 . The refinement of structure with I≥3σ(I) for 1819 reflections converged at R =0.045. The coordination geometry around the Sn atom is best described as an askew pentagonal bipyramid, in which four carboxylate oxygen atoms ( Sn(1)-O(5), Sn(1)-O(5a)=2.099 and Sn(1)-O(4), Sn(1)-O(4a)=2.158 ) and an oxygen atom from an aqua ligand comprise the pentagonal plane, with two butyl groups occupying axial positions. 展开更多
关键词 DIORGANOTIN dicarboxylate crystal structure synthesis.
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