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Synthesis, Crystal Structure and Properties of a New Coordination Polymer Constructed with 3-(4-hydroxypyridinium-1-yl)phthalic Acid
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作者 李付安 白素贞 +1 位作者 李兴武 陈权 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第5期701-706,共6页
A new nickel coordination polymer {[Ni(dpa)(bpe)(H2O)]2}n(1) has been hydro-thermally synthesized, and structurally characterized by UV spectroscopy, elemental analyses and single-crystal X-ray diffraction(H2... A new nickel coordination polymer {[Ni(dpa)(bpe)(H2O)]2}n(1) has been hydro-thermally synthesized, and structurally characterized by UV spectroscopy, elemental analyses and single-crystal X-ray diffraction(H2dpa=3-(4-hydroxypyridinium-1-yl) phthalic acid, bpe=μ-1,2-di(4-pyridyl) ethylene). It crystallizes in the triclinic system, space group P1 with a=8.779(2), b=10.909(3), c=12.739(3), α=72.45(2), β=75.13(2), γ=86.47(2)°, V=1124.1(5) 3, Z=2, Mr=516.14, Dc=1.525 g/cm3, μ=0.912 mm-1, Rint=0.0532, F(000)=532, the final R=0.0523 and wR=0.1089 for 3949 observed reflections(I〉2σ(I)). The coordination around the Ni center is a distorted octahedron coordination geometry involving two protonated H2dpa ligands, two bpe ligands, and one coordinated H2O molecule. The dpa2- anion, as a bridging ligand, connects two Ni centers to form binuclear units, which are linked together by the bpe ligands to form two-dimensional layers, and the interlayer hydrogen bonding further extends the 2D sheet into a 3D supramolecular framework. 展开更多
关键词 3-(4-hydroxypyridinium-1-yl) phthalic acid pOLYMER binuclear nickel unit
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MicroRNA-502-3p regulates GABAergic synapse function in hippocampal neurons 被引量:4
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作者 Bhupender Sharma Melissa MTorres +2 位作者 Sheryl Rodriguez Laxman Gangwani Subodh Kumar 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第12期2698-2707,共10页
Gamma-aminobutyric acid(GABA)ergic neurons,the most abundant inhibitory neurons in the human brain,have been found to be reduced in many neurological disorders,including Alzheimer's disease and Alzheimer's dis... Gamma-aminobutyric acid(GABA)ergic neurons,the most abundant inhibitory neurons in the human brain,have been found to be reduced in many neurological disorders,including Alzheimer's disease and Alzheimer's disease-related dementia.Our previous study identified the upregulation of microRNA-502-3p(miR-502-3p)and downregulation of GABA type A receptor subunitα-1 in Alzheimer's disease synapses.This study investigated a new molecular relationship between miR-502-3p and GABAergic synapse function.In vitro studies were perfo rmed using the mouse hippocampal neuronal cell line HT22 and miR-502-3p agomiRs and antagomiRs.In silico analysis identified multiple binding sites of miR-502-3p at GABA type A receptor subunitα-1 mRNA.Luciferase assay confirmed that miR-502-3p targets the GABA type A receptor subunitα-1 gene and suppresses the luciferase activity.Furthermore,quantitative reve rse transcription-polymerase chain reaction,miRNA in situ hybridization,immunoblotting,and immunostaining analysis confirmed that overexpression of miR-502-3p reduced the GABA type A receptor subunitα-1 level,while suppression of miR-502-3p increased the level of GABA type A receptor subunitα-1 protein.Notably,as a result of the overexpression of miR-502-3p,cell viability was found to be reduced,and the population of necrotic cells was found to be increased.The whole cell patch-clamp analysis of human-GABA receptor A-α1/β3/γ2L human embryonic kidney(HEK)recombinant cell line also showed that overexpression of miR-502-3p reduced the GABA current and overall GABA function,suggesting a negative correlation between miR-502-3p levels and GABAergic synapse function.Additionally,the levels of proteins associated with Alzheimer s disease were high with miR-502-3p overexpression and reduced with miR-502-3p suppression.The present study provides insight into the molecular mechanism of regulation of GABAergic synapses by miR-502-3p.We propose that micro-RNA,in particular miR-502-3p,could be a potential therapeutic to rget to modulate GABAergic synapse function in neurological disorders,including Alzheimer's disease and Alzheimer's diseaserelated dementia. 展开更多
关键词 Alzheimer's disease GABAergic synapse gamma-aminobutyric acid type A receptor subunitα-1(GABRα1) microRNA-502-3p(miR-502-3p) miRNA in situ hybridization pATCH-CLAMp
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Effects of ω-3 fatty acids on toll-like receptor 4 and nuclear factor-κB p56 in lungs of rats with severe acute pancreatitis 被引量:12
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作者 Bin Wang Xiao-Wei Wu +4 位作者 Mei-Xia Guo Min-Li Li Xiao-Bing Xu Xin-Xin Jin Xiao-Hua Zhang 《World Journal of Gastroenterology》 SCIE CAS 2016年第44期9784-9793,共10页
AIM To determine the effects of ω-3 fatty acids(ω-3FA) on the toll-like receptor 4(TLR4)/nuclear factor κB p56(NF-κBp56) signal pathway in the lungs of rats with severe acute pancreatitis(SAP).METHODS A total of 5... AIM To determine the effects of ω-3 fatty acids(ω-3FA) on the toll-like receptor 4(TLR4)/nuclear factor κB p56(NF-κBp56) signal pathway in the lungs of rats with severe acute pancreatitis(SAP).METHODS A total of 56 Sprague-Dawley rats were randomly divided into 4 groups: control group, SAP-saline group, SAP-soybean oil group and SAP-ω-3FA group. SAP was induced by the retrograde infusion of sodium taurocholate into the pancreatic duct. The expression of TLR4 and NF-κBp56 in the lungs was evaluated by immunohistochemistry and Western blot analysis. The levels of inflammatory cytokines interleukin-6 and tumor necrosis factor-alpha in the lungs were measured by enzyme-linked immunosorbent assay. RESULTS The expression of TLR4 and NF-κBp56 in lungs and of inflammatory cytokines in serum significantly increased in the SAP group compared with the control group(P < 0.05), but was significantly decreased in the ω-3FA group compared with the soybean oil group at 12 and 24 h(P < 0.05).CONCLUSION During the initial stage of SAP, ω-3FA can efficiently lower the inflammatory response and reduce lung injury by triggering the TLR4/NF-κBp56 signal pathway. 展开更多
关键词 Severe acute pancreatitis ω-3 fatty acids Lung injury Toll-like receptor 4 Nuclear factor-κB p56 CYTOKINE
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18β-glycyrrhetinic acid inhibits proliferation of gastric cancer cells through regulating the miR-345-5p/TGM2 signaling pathway 被引量:3
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作者 Xia Li Xiao-Ling Ma +8 位作者 Yi Nan Yu-Hua Du Yi Yang Dou-Dou Lu Jun-Fei Zhang Yan Chen Lei Zhang Yang Niu Ling Yuan 《World Journal of Gastroenterology》 SCIE CAS 2023年第23期3622-3644,共23页
BACKGROUND Gastric cancer(GC)is a common gastrointestinal malignancy worldwide.Based on cancer-related mortality,the current prevention and treatment strategies for GC still show poor clinical results.Therefore,it is ... BACKGROUND Gastric cancer(GC)is a common gastrointestinal malignancy worldwide.Based on cancer-related mortality,the current prevention and treatment strategies for GC still show poor clinical results.Therefore,it is important to find effective drug treatment targets.AIM To explore the molecular mechanism of 18β-glycyrrhetinic acid(18β-GRA)regulating the miR-345-5p/TGM2 signaling pathway to inhibit the proliferation of GC cells.METHODS CCK-8 assay was used to determine the effect of 18β-GRA on the survival rate of GES-1 cells and AGS and HGC-27 cells.Cell cycle and apoptosis were detected by flow cytometry,cell migration was detected by a wound healing assay,the effect of 18β-GRA on subcutaneous tumor growth in BALB/c nude mice was investigated,and the cell autophagy level was determined by MDC staining.TMT proteomic analysis was used to detect the differentially expressed autophagy-related proteins in GC cells after 18β-GRA intervention,and then the protein-protein interaction was predicted using STRING(https://string-db.org/).MicroRNAs(miRNAs)transcriptome analysis was used to detect the miRNA differential expression profile,and use miRBase(https://www.mirbase/)and TargetScan(https://www.targetscan.org/)to predict the miRNA and complementary binding sites.Quantitative real-time polymerase chain reaction was used to detect the expression level of miRNA in 18β-GRA treated cells,and western blot was used to detect the expression of autophagy related proteins.Finally,the effect of miR-345-5p on GC cells was verified by mir-345-5p overexpression.RESULTS 18β-GRA could inhibit GC cells viability,promote cell apoptosis,block cell cycle,reduce cell wound healing ability,and inhibit the GC cells growth in vivo.MDC staining results showed that 18β-GRA could promote autophagy in GC cells.By TMT proteomic analysis and miRNAs transcriptome analysis,it was concluded that 18β-GRA could down-regulate TGM2 expression and up-regulate miR-345-5p expression in GC cells.Subsequently,we verified that TGM2 is the target of miR-345-5p,and that overexpression of miR-345-5p significantly inhibited the protein expression level of TGM2.Western blot showed that the expression of autophagy-related proteins of TGM2 and p62 was significantly reduced,and LC3II,ULK1 and AMPK expression was significantly increased in GC cells treated with 18β-GRA.Overexpression of miR-345-5p not only inhibited the expression of TGM2,but also inhibited the proliferation of GC cells by promoting cell apoptosis and arresting cell cycle.CONCLUSION 18β-GRA inhibits the proliferation of GC cells and promotes autophagy by regulating the miR-345-5p/TGM2 signaling pathway. 展开更多
关键词 18β-glycyrrhetinic acid Gastric cancer MiR-345-5p TGM2 pROLIFERATION AUTOpHAGY
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18β-glycyrrhetinic acid promotes gastric cancer cell autophagy and inhibits proliferation by regulating miR-328-3p/signal transducer and activator of transcription 3 被引量:1
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作者 Yi Yang Yi Nan +7 位作者 Yu-Hua Du Shi-Cong Huang Dou-Dou Lu Jun-Fei Zhang Xia Li Yan Chen Lei Zhang Ling Yuan 《World Journal of Gastroenterology》 SCIE CAS 2023年第27期4317-4333,共17页
BACKGROUND Gastric cancer(GC)is one of the most common cancer types worldwide,and its prevention and treatment methods have garnered much attention.As the active ingredient of licorice,18β-glycyrrhetinic acid(18β-GR... BACKGROUND Gastric cancer(GC)is one of the most common cancer types worldwide,and its prevention and treatment methods have garnered much attention.As the active ingredient of licorice,18β-glycyrrhetinic acid(18β-GRA)has a variety of pharmacological effects.The aim of this study was to explore the effective target of 18β-GRA in the treatment of GC,in order to provide effective ideas for the clinical prevention and treatment of GC.AIM To investigate the mechanism of 18β-GRA in inhibiting cell proliferation and promoting autophagy flux in GC cells.METHODS Whole transcriptomic analyses were used to analyze and screen differentially expressed microRNAs(miRNAs)in GC cells after 18β-GRA intervention.Lentivirus-transfected GC cells and the Cell Counting Kit-8 were used to detect cell proliferation ability,cell colony formation ability was detected by the clone formation assay,and flow cytometry was used to detect the cell cycle and apoptosis.A nude mouse transplantation tumor model of GC cells was constructed to verify the effect of miR-328-3p overexpression on the tumorigenicity of GC cells.Tumor tissue morphology was observed by hematoxylin and eosin staining,and microtubule-associated protein light chain 3(LC3)expression was detected by immunohistochemistry.TransmiR,STRING,and miRWalk databases were used to predict the relationship between miR-328-3p and signal transducer and activator of transcription 3(STAT3)-related information.Expression of STAT3 mRNA and miR-328-3p was detected by quantitative polymerase chain reaction(qPCR)and the expression levels of STAT3,phosphorylated STAT3(p-STAT3),and LC3 were detected by western blot analysis.The targeted relationship between miR-328-3p and STAT3 was detected using the dual-luciferase reporter gene system.AGS cells were infected with monomeric red fluorescent protein-green fluorescent protein-LC3 adenovirus double label.LC3 was labeled and autophagy flow was observed under a confocal laser microscope.RESULTS The expression of miR-328-3p was significantly upregulated after 18β-GRA intervention in AGS cells(P=4.51E-06).Overexpression of miR-328-3p inhibited GC cell proliferation and colony formation ability,arrested the cell cycle in the G0/G1 phase,promoted cell apoptosis,and inhibited the growth of subcutaneous tumors in BALB/c nude mice(P<0.01).No obvious necrosis was observed in the tumor tissue in the negative control group(no drug intervention or lentivirus transfection)and vector group(the blank vector for lentivirus transfection),and more cells were loose and necrotic in the miR-328-3p group.Bioinformatics tools predicted that miR-328-3p has a targeting relationship with STAT3,and STAT3 was closely related to autophagy markers such as p62.After overexpressing miR-328-3p,the expression level of STAT3 mRNA was significantly decreased(P<0.01)and p-STAT3 was downregulated(P<0.05).The dual-luciferase reporter gene assay showed that the luciferase activity of miR-328-3p and STAT33’untranslated regions of the wild-type reporter vector group was significantly decreased(P<0.001).Overexpressed miR-328-3p combined with bafilomycin A1(Baf A1)was used to detect the expression of LC3 II.Compared with the vector group,the expression level of LC3 II in the overexpressed miR-328-3p group was downregulated(P<0.05),and compared with the Baf A1 group,the expression level of LC3 II in the overexpressed miR-328-3p+Baf A1 group was upregulated(P<0.01).The expression of LC3 II was detected after intervention of 18β-GRA in GC cells,and the results were consistent with the results of miR-328-3p overexpression(P<0.05).Additional studies showed that 18β-GRA promoted autophagy flow by promoting autophagosome synthesis(P<0.001).qPCR showed that the expression of STAT3 mRNA was downregulated after drug intervention(P<0.05).Western blot analysis showed that the expression levels of STAT3 and p-STAT3 were significantly downregulated after drug intervention(P<0.05).CONCLUSION 18β-GRA promotes the synthesis of autophagosomes and inhibits GC cell proliferation by regulating the miR-328-3p/STAT3 signaling pathway. 展开更多
关键词 18β-glycyrrhetinic acid miR-328-3p Signal transducer and activator of transcription 3 Cell proliferation Autophagy flow
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Cytochrome P450 monooxygenase-mediated eicosanoid pathway:A potential mechanistic linkage between dietary fatty acid consumption and colon cancer risk
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作者 Weicang Wang Jianan Zhang Guodong Zhang 《Food Science and Human Wellness》 SCIE 2019年第4期337-343,共7页
Human consumption of linoleic acid(LA,18:2ω-6,abundant in vegetable oils)is very high.Animal experiments showed that excessive LA intake increased azoxymethane-induced colon tumorigenesis,however,the impact of excess... Human consumption of linoleic acid(LA,18:2ω-6,abundant in vegetable oils)is very high.Animal experiments showed that excessive LA intake increased azoxymethane-induced colon tumorigenesis,however,the impact of excessive LA on colon cancer in human is not conclusive,making it difficult to make dietary recommendations for optimal intake of LA.Understanding the molecular mechanisms of LA on colon tumorigenesis could help to clarify its health effect,and facilitate development of mechanismbased strategies for preventing colon cancer.Recent studies show that the previously unappreciated cytochrome P450 monooxygenase-mediated eicosanoid pathway is upregulated in colon cancer and plays critical roles in its pathogenesis,and could contribute to the effects of dietary LA,as well asω-3 fatty acids,on colon tumorigenesis.In this review,we will discuss recent studies about the roles of cytochrome P450 monooxygenases in fatty acid metabolism and its roles in colonic inflammation and colon cancer,and how this information could help us to clarify the health impacts of dietary fatty acids. 展开更多
关键词 Linoleic acid polyunsaturated fatty acids ω-3 Fatty acids Colon cancer Colonic inflammation Cytochrome p450 EICOSANOIDS
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ICP-AES法同时测定精对苯二甲酸中微量金属元素 被引量:6
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作者 钱彦虎 《理化检验(化学分册)》 CAS CSCD 北大核心 2004年第7期403-404,407,共3页
采用等离子体原子发射光谱法(ICP AES)测定精对苯二甲酸(PTA)中微量金属元素。讨论了影响因素,优化了操作参数。钠、铁、钴、锰、镍、铬六种元素回收率在94.0%~104.0%之间。此法对其它有机体中的金属元素测定有参考价值。
关键词 ICp-AES 精对苯二甲酸
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Co/MOFs-Pt修饰电极循环伏安法测定铅离子 被引量:3
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作者 黄华 任忠吕 +2 位作者 何艳梅 周进康 龙攀峰 《中北大学学报(自然科学版)》 北大核心 2017年第4期480-486,共7页
以对苯二甲酸、硝酸钴为原料,在N,N-二甲基甲酰胺溶剂中进行溶剂热反应合成钴金属有机框架化合物(Co/MOFs),利用X射线衍射、傅里叶红外光谱和比表面分析对产物进行表征.将Co/MOFs与纳米铂粒子复合修饰的玻碳电极(Co/MOFs-Pt),在醋酸盐... 以对苯二甲酸、硝酸钴为原料,在N,N-二甲基甲酰胺溶剂中进行溶剂热反应合成钴金属有机框架化合物(Co/MOFs),利用X射线衍射、傅里叶红外光谱和比表面分析对产物进行表征.将Co/MOFs与纳米铂粒子复合修饰的玻碳电极(Co/MOFs-Pt),在醋酸盐缓冲溶液中采用循环伏安法测定了铅离子Pb(Ⅱ)的电化学行为.研究了不同条件对Pb(Ⅱ)电化学测定的影响.结果表明,在醋酸盐缓冲溶液中,pH=5.0,扫描速度为120mV/s时,进行循环伏安法测定,在-0.76V处出现一个峰形较好的特征吸收峰;峰电流与Pb(Ⅱ)浓度在0.5~30μmol/L范围内呈良好的线性关系,相关系数为0.999 6,检出限为0.012μmol/L;连续测定6周,电极表现出较好的稳定性. 展开更多
关键词 对苯二甲酸 金属有机框架化合物 修饰电极 循环伏安法 pb(Ⅱ)
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配合物Na_2(4-apyH)_2[CoCl_2(H_2O)_4·(tp)_2]的合成及晶体结构
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作者 于文娟 陈宏基 +1 位作者 郭静仪 郑文杰 《暨南大学学报(自然科学与医学版)》 CAS CSCD 2003年第1期50-54,共5页
 为了研究过渡金属借助氢键引导的自组装,合成了线性刚性配体对二苯甲酸与钴(II)、4-氨基吡啶和水的配合物Na2(4-apyH)2[CoCl2(H2O)4·(tp)2](tpH2=p-phthalicacid,4-apy=4-aminopyridine).并采用X射线衍射法对配合物进行了晶体结...  为了研究过渡金属借助氢键引导的自组装,合成了线性刚性配体对二苯甲酸与钴(II)、4-氨基吡啶和水的配合物Na2(4-apyH)2[CoCl2(H2O)4·(tp)2](tpH2=p-phthalicacid,4-apy=4-aminopyridine).并采用X射线衍射法对配合物进行了晶体结构的测定.结果是结构简式C26H30CoN4O12Na2Cl2,相对分子质量Mr=766 35,三斜晶系,空间群为P1,晶胞参数a=7 875(2) A(1 A=10-10m),b=9 818(2) A,c=10 892(2) A,α=77.26(3)°,β=77 31(3)°,γ=84 22(3)°,V=800 1(3) A3,Z=1,Dc=1 590g·cm-3,μ=0 798mm-1,F(000)=393.结果表明:晶体分子中含三维氢键网状结构,每单元中心都以CoCl2O4六配位方式形成八面体构型. 展开更多
关键词 Na2(4-apyH)2[CoCl2(H2O)4·(tp)2] 对氨基苯甲酸 相对分子质量 晶体结构 合成 钴配合物
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Uncoupling tumor necrosis factor-αand interleukin-10 at tumor immune microenvironment of breast cancer through miR-17-5p/MALAT-1/H19 circuit
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作者 RAGHDA A.SOLIMAN RANA A.YOUNESS +5 位作者 TAMER M.MANIE EMAD KHALLAF MOHAMED EL-SHAZLY MONA ABDELMOHSEN HEBA HANDOUSSA MOHAMED Z.GAD 《BIOCELL》 SCIE 2022年第3期769-783,共15页
Triple Negative Breast Cancer(TNBC)immunotherapy has recently shown promising approach.However,some TNBC patients presented with resistance.One of the reasons was attributed to the excessive release of cytokines at th... Triple Negative Breast Cancer(TNBC)immunotherapy has recently shown promising approach.However,some TNBC patients presented with resistance.One of the reasons was attributed to the excessive release of cytokines at the tumor microenvironment(TME)such as Tumor necrosis factor alpha(TNF-α)and Interleukin-10(IL-10).Fine regulation of these cytokines’levels via non-coding RNAs(ncRNAs)might alleviate the immune quiescent nature of TME at TNBC tumors.However,the extrapolation of ncRNAs as therapeutic tools is highly challenging.Therefore,disentanglement the nature for the isolation of natural compounds that could modulate the ncRNAs and their respective targets is an applicable translational therapeutic approach.Hence,this study aimed to targeting the chief immune suppressive cytokines at the TME(TNF-αand IL-10)via ncRNAs and to examine the effects of Rosemary aerial parts extract on the expression levels of these ncRNAs in TNBC.Results revealed miR-17-5p as a dual regulator of TNF-αand IL-10.Moreover,an intricate interaction has been shown between miR-17-5p and the oncogenic lncRNAs:MALAT1 and H19.Knocking down of MALAT1 and/or H19 caused an induction in miR-17-5p and reduction in TNF-αand IL-10 expression levels.miR-17-5p was found to be down-regulated,while TNF-α,IL-10,MALAT1 and H19 were up-regulated in BC patients.Forced expression of miR-17-5p in MDA-MB-231 cells reduced TNF-α,IL-10,MALAT1 and H19 expression levels,as well as several BC hallmarks.In a translational approach,ursolic acid(UA)isolated from rosemary induced the expression of miR-17-5p,MALAT1 and decreased H19 expression levels.In conclusion,this study suggests miR-17-5p as a tumor suppressor and an immune-activator miRNA in BC through tuning up the immunological targets TNF-α,IL-10 at the TME and the oncological mediators MALAT1 and H19 lncRNAs. 展开更多
关键词 Breast cancer Tumor microenvironment CYTOKINES TNF-α IL-10 miR-17-5p MALAT1 H19 lncRNAs miRNA Ursolic acid
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PTA废液回收利用技术 被引量:14
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作者 于文敦 刘晓东 +1 位作者 孙秀云 王连军 《化工环保》 CAS CSCD 北大核心 2001年第5期290-293,共4页
介绍了从精对苯二甲酸 (PTA )废液中回收醋酸 ,邻、对苯二甲酸 ,醋酸钴锰盐的回收工艺。醋酸得率为 90 % ,邻、对苯二甲酸得率为 70 % ,醋酸钴锰盐得率为 95 %。该技术成熟、合理 。
关键词 精对苯二甲酸废液 醋酸 苯二甲酸 醋酸钴锰盐 综合利用 pTA 废水处理
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稀土(铕-铽)-18冠6-对苯二甲酸配合物的荧光性能 被引量:11
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作者 赵永亮 安晓萍 +2 位作者 赵凤英 燕来 宝金荣 《发光学报》 EI CAS CSCD 北大核心 2004年第5期551-555,共5页
以对苯二甲酸(L′)为桥联配体,18冠6(L)为配体,稀土(Eu Tb)为中心离子,合成了一系列超分子化合物,对其进行了元素分析,红外光谱及荧光性能测量。确定了配合物的组成为(Eu1-xTbx)2L2L′(ClO4)4·H2O(6+3x);推测出Eu3+离子直接与冠醚... 以对苯二甲酸(L′)为桥联配体,18冠6(L)为配体,稀土(Eu Tb)为中心离子,合成了一系列超分子化合物,对其进行了元素分析,红外光谱及荧光性能测量。确定了配合物的组成为(Eu1-xTbx)2L2L′(ClO4)4·H2O(6+3x);推测出Eu3+离子直接与冠醚氧原子配位,而较小半径的Tb3+与18冠6则通过H2O配位。H2O分子与冠醚氧原子以氢键形式连结,对苯二甲酸以双齿形式桥联两个稀土离子冠醚配合物,形成双核结构单元;在此配合物中,Tb3+离子对Eu3+离子的发光有一定的敏化作用,而Eu3+离子对Tb3+离子的荧光却有强的猝灭作用。 展开更多
关键词 稀土(Eu-Tb)配合物 18冠6 对苯二甲酸 荧光性能
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微波辐射下双(2-苯并咪唑基)苯的合成 被引量:11
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作者 宋林青 徐贤伦 谭干祖 《精细化工》 EI CAS CSCD 北大核心 2000年第5期256-257,共2页
微波辐射条件下 ,利用对苯二甲酸和间苯二甲酸与邻苯二胺在多磷酸中的缩合反应 ,合成了 1 ,4 双 ( 2 苯并咪唑基 )苯和 1 ,3 双 ( 2 苯并咪唑基 )苯两种化合物 ,反应时间 1 2min ,产率分别为 77%和 84% ,该条件下的反应速度分别是常... 微波辐射条件下 ,利用对苯二甲酸和间苯二甲酸与邻苯二胺在多磷酸中的缩合反应 ,合成了 1 ,4 双 ( 2 苯并咪唑基 )苯和 1 ,3 双 ( 2 苯并咪唑基 )苯两种化合物 ,反应时间 1 2min ,产率分别为 77%和 84% ,该条件下的反应速度分别是常规条件下反应速度的 50和 2 0倍 ,且产率与常规反应相当。 展开更多
关键词 苯并咪唑基 微波辐射 合成 有机药物
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对-苯二甲酸邻菲罗啉铕镧配合物的红外光谱及荧光光谱研究 被引量:21
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作者 赵永亮 赵凤英 《中国稀土学报》 CAS CSCD 北大核心 2001年第5期398-401,共4页
用对 苯二甲酸铵和邻菲罗啉与氯化铕和氯化镧在乙醇 水溶液中反应 ,合成了对 苯二甲酸邻菲罗啉铕镧异核稀土配合物 ,测定了配合物的C ,H ,N和稀土元素的含量、红外光谱、紫外光谱及荧光光谱 ,确定了配合物的组成。结果表明 ,羧基氧和... 用对 苯二甲酸铵和邻菲罗啉与氯化铕和氯化镧在乙醇 水溶液中反应 ,合成了对 苯二甲酸邻菲罗啉铕镧异核稀土配合物 ,测定了配合物的C ,H ,N和稀土元素的含量、红外光谱、紫外光谱及荧光光谱 ,确定了配合物的组成。结果表明 ,羧基氧和邻菲罗啉氮原子均与稀土离子配位 ,桥联配体对 苯二甲酸根可有效的传送能量 。 展开更多
关键词 稀土 邻菲罗啉 -苯地甲酸 配合物 红外光谱 荧光光谱 桥联配体
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化纤废水中污染物对大型(Daphnia magna)繁殖的影响 被引量:7
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作者 袁有宪 王会平 《中国环境科学》 EI CAS CSSCI CSCD 北大核心 1998年第2期117-120,共4页
为研究化纤工业对水域生态的长期效应,首次在实验室研究了化纤工业废水中主要污染物乙醛、对苯二甲酸、乙二醇对大型(Daphniamagna)生殖周期和繁殖数量的影响。实验结果表明,乙醛浓度低于6mg/L时,对大型首次... 为研究化纤工业对水域生态的长期效应,首次在实验室研究了化纤工业废水中主要污染物乙醛、对苯二甲酸、乙二醇对大型(Daphniamagna)生殖周期和繁殖数量的影响。实验结果表明,乙醛浓度低于6mg/L时,对大型首次和第二次生殖周期无影响。7~10mg/L时,使首次生殖周期推迟1~2d,使第二次生殖周期提前1~2d。对苯二甲酸浓度32mg/L以下时,对首次和第二次生殖周期基本无影响;64~256mg/L时,使首次生殖周期均推迟1~2d,第二次生殖周期均缩短1~2d。乙二醇浓度在1000mg/L以下时,对首次生殖周期无影响;2000~4000mg/L时,推迟首次生殖周期1d;浓度低于4000mg/L时,对第二次生殖周期无影响。乙醛浓度在5mg/L以下时,对首次和第二次繁殖数量无显著影响,浓度在6~10mg/L时,显著降低其繁殖数量,分别降低38.3%~74.1%和12.8%~65.3%。对苯二甲酸浓度低于32mg/L时,对首次繁殖数量无显著影响,浓度在64~256mg/L时,降低首次繁殖数量62.9%~75.3%;浓度低于16mg/L时,对第二次繁殖数量无显著影响,浓度在32~256mg/L时,使第二次繁殖数? 展开更多
关键词 大型溲 繁殖 化学纤维 废水 污染物 水体污染
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对苯二甲酸-铕-钇配合物的合成及荧光性质 被引量:3
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作者 沈新峰 杨良准 +3 位作者 张晨 张兰芬 任黎雯 余锡宾 《化学研究》 CAS 2007年第4期24-26,32,共4页
以对苯二甲酸(H2L)为配体,合成了系列(Eu1-xYx)2L3.3H2O固体粉末配合物.通过元素分析、紫外吸收光谱、X射线衍射和红外光谱确定了配合物的组成和结构,并通过荧光光谱研究了它们的荧光性质.结果表明钇掺入配合物后,能增强Eu3+的特征荧光... 以对苯二甲酸(H2L)为配体,合成了系列(Eu1-xYx)2L3.3H2O固体粉末配合物.通过元素分析、紫外吸收光谱、X射线衍射和红外光谱确定了配合物的组成和结构,并通过荧光光谱研究了它们的荧光性质.结果表明钇掺入配合物后,能增强Eu3+的特征荧光,当铕与钇的摩尔比为0.05∶0.95时荧光强度最强. 展开更多
关键词 对苯二甲酸 配合物 荧光光谱
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新型生物流化床处理PTA废水的研究 被引量:3
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作者 范俊 沈树宝 陈英文 《工业水处理》 CAS CSCD 2004年第8期40-42,共3页
在传统的一体式气-液-固三相内环流反应器的基础上提出并设计了一种新型分段式可调生物流化床反应器,用于处理对苯二甲酸实际生产废水,取得了良好的效果;同时初步构建了该反应器的动力学模型,并对该动力学模型进行了分析。
关键词 生物流化床 对苯二甲酸 生化
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2,4,6-三吡啶基三嗪-芳香羧酸镝配合物的合成及其荧光性能 被引量:1
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作者 李海燕 赵永亮 张雁冰 《发光学报》 EI CAS CSCD 北大核心 2011年第9期869-873,共5页
分别以2,4,6-三吡啶基三嗪(TPTZ)、对羟基苯甲酸和对苯二甲酸为配体,以Dy3+为中心合成了不同组成的5种配合物。对其进行了元素分析、紫外光谱、红外光谱、荧光激发和发射光谱的测定。推测配合物的组成分别为:(1)Dy(TPTZ)(NO3)3(C2H5OH).... 分别以2,4,6-三吡啶基三嗪(TPTZ)、对羟基苯甲酸和对苯二甲酸为配体,以Dy3+为中心合成了不同组成的5种配合物。对其进行了元素分析、紫外光谱、红外光谱、荧光激发和发射光谱的测定。推测配合物的组成分别为:(1)Dy(TPTZ)(NO3)3(C2H5OH).H2O;(2)Dy(TPTZ)2(NO3)3(C2H5OH).H2O;(3)Dy2(TPTZ)(NO3)6(C2H5OH).2H2O;(4)Dy(TPTZ)(C7H5O3)3(C2H5OH).2H2O;(5)Dy2(TPTZ)2-(C8H4O4)(NO3)4(C2H5OH).H2O。硝酸根的氧原子、芳香酸的羧基氧和稀土离子配位,TPTZ以主配位点和中配位点的氮原子与稀土离子成键。配合物的形成对配体的共轭π-π*跃迁影响不大。荧光强度测试表明,硝酸根、不同的芳香羧酸作为阴离子配体的镝配合物的发光强度有很大差别。芳香羧酸配体对镝配合物的荧光增强最大,镝离子浓度高,荧光强度也高。配合物(2)荧光强度大于配合物(1),配合物(3)荧光强度大于配合物(2),可见配体TPTZ多或者发光离子浓度高则配合物发光强度高;配合物(4)荧光强度强于配合物(1),表明对羟基苯甲酸吸收和传递光能强于硝酸根;配合物(5)的荧光强度是5个配合物中最高的,表明对苯二甲酸三重态能级与Dy3+的最低激发态能级匹配,对光的吸收和传递也好,同时也看出发光的Dy3+离子量增加,配合物的发光强度增强。 展开更多
关键词 2 4 6-三吡啶基三嗪 对羟基苯甲酸 对苯二甲酸 镝配合物
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P_6对苯型大理石树脂的开发研究 被引量:1
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作者 齐双春 邢广恩 《河北师范大学学报(自然科学版)》 CAS 北大核心 2005年第1期61-65,共5页
选用合适级别的对苯二甲酸、对苯二酚和环烷酸铜的复合阻聚体系,制备出了性能优良、成本较低的对苯型大理石专用树脂.其最佳工艺条件:饱和酸与不饱和酸的摩尔比为1.00,n(一缩二乙二醇)∶n(醇)=1.0∶10.0,3#催化剂用量为0.10%,反应温度为... 选用合适级别的对苯二甲酸、对苯二酚和环烷酸铜的复合阻聚体系,制备出了性能优良、成本较低的对苯型大理石专用树脂.其最佳工艺条件:饱和酸与不饱和酸的摩尔比为1.00,n(一缩二乙二醇)∶n(醇)=1.0∶10.0,3#催化剂用量为0.10%,反应温度为230~240℃. 展开更多
关键词 大理石树脂 不饱和聚酯树脂 对苯二甲酸
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高效液相色谱法测定PET瓶中对苯二甲酸迁移量的不确定度评定 被引量:6
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作者 刘肖肖 高晓哲 +1 位作者 陈畅 赵晓甫 《标准科学》 2019年第4期144-148,共5页
本文依据GB 31604.21-2016《食品安全国家标准食品接触材料及制品对苯二甲酸迁移量的测定》,采用高效液相色谱研究食品包装PET塑料瓶水基模拟物中对苯二甲酸迁移量不确定度的大小。并建立数学模型,从标准溶液配制、标准曲线拟合、测量... 本文依据GB 31604.21-2016《食品安全国家标准食品接触材料及制品对苯二甲酸迁移量的测定》,采用高效液相色谱研究食品包装PET塑料瓶水基模拟物中对苯二甲酸迁移量不确定度的大小。并建立数学模型,从标准溶液配制、标准曲线拟合、测量结果的重复性等方面,分析不确定度来源,然后计算合成不确定度。结果显示标准溶液配制中天平的最大允许误差对对苯二甲酸迁移量的影响最大,其次是校准曲线拟合求浓度过程的影响。日常检验中要对仪器进行检定和期间核查,保持仪器的稳定性和高灵敏度。 展开更多
关键词 pET塑料瓶 对苯二甲酸迁移量 不确定度 高效液相色谱法
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