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Lanthanum(Ⅲ) sorption studies on poly[dibenzo-18-crown-6] and its separation from uranium(Ⅵ) and thorium(Ⅳ) in L-valine medium 被引量:2
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作者 S.R.Sabale D.V.Jadhav B.S.Mohite 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第5期825-829,共5页
The sorption study of La(Ⅲ) was carried out on poly[dibenzo-18-crown-6] and L-valine medium. The quantitative adsorption of La(Ⅲ) was found at 1×10-2 to 1×10-5 mol/L L-valine. The various eluting agents we... The sorption study of La(Ⅲ) was carried out on poly[dibenzo-18-crown-6] and L-valine medium. The quantitative adsorption of La(Ⅲ) was found at 1×10-2 to 1×10-5 mol/L L-valine. The various eluting agents were found efficient eluents for La(Ⅲ). The capacity of crown polymer for La(Ⅲ) was found to be 0.43 ±0.01 mmol/g. The tolerance limit of various cations and anions for La(Ⅲ) was determined. La(Ⅲ) was quantitatively separated from other metal ions in binary as well as multicomponent mixtures. The study was extended to sequential separation of La(Ⅲ), U(VI) and Th(IV). The good separation yields were obtained and had good reproducibility (±2%). The method incorporated the determination of La(Ⅲ) in real sample. The method was simple, rapid and selective. 展开更多
关键词 La(Ⅲ) L-VALINE poly[dibenzo-18-crown-6] SORPTION SEPARATION rare earths
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Surface Electrostatic Potentials of Polychlorinated Dibenzo-p-dioxins and Their Applications in the Quantitative Structure-properties Relationships 被引量:3
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作者 许惠英 王维 柴水英 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第6期793-798,共6页
Polychlorinated dibenzo-p-dioxins(PCDDs) are a group of important persistent organic pollutants.They are highly toxic and persistent in environment.In the present study,geometrical optimization and electrostatic pot... Polychlorinated dibenzo-p-dioxins(PCDDs) are a group of important persistent organic pollutants.They are highly toxic and persistent in environment.In the present study,geometrical optimization and electrostatic potential calculations have been performed for 75 PCDD congeners and dibenzo-p-dioxin(DD) at the HF/6-31G* level of theory.A number of statistically based parameters have been extracted.Linear relationships between vapor pressures(logpL),aqueous solubilities(logSw),n-octanol/water partition coefficients(logKow) of PCDDs and structural descriptors have been established by stepwise linear regression analysis.The result shows that the quantities derived from the surface electrostatic potentials Vmin,Π,and Vs,av+,together with Vmc(the molecular volume) and ELUMO(the energy of the lowest unoccupied molecular orbital) can be well used to express the quantitative structure-property relationships of PCDDs.Predictive capabilities of the models have also been demonstrated by leave-one-out cross-validation with the cross-validated correlation coefficient(Rcv) above 0.97.Based on these QSPR models,the predicted values have been presented for those PCDD congeners whose experimentally determined physicochemical properties are unavailable. 展开更多
关键词 QSPR polychlorinated dibenzo-p-dioxin molecular electrostatic potential
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Synergistic Effect in Mixed Capillary Gas Chromatographic Stationap Phases Containing Heptakis(2,3,6-tri-o-pentyl)-β-cyclodextrin and Dibenzo-18-crown-6 被引量:1
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作者 Li Ming YUAN Ruo Nong FU +3 位作者 Xue Xian CHEN Shi Hong GUl Rong Ji DAI (Chemistry Department of Yunnan Normal University.Kunming 650092)(Department of Chemical Engineering.Beijing institute of Technology,BEijing 100081)(Solar Energy Research Institute ofyunna 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第3期223-226,共4页
used-silical capillary columns containing heptakis(2、3、6-tri-o-pentyl)-β-cyclodextrinand dibenzo-18-crown-6 were prepared.By studying the selectivity of mixed stationary phases forsome solute pairs.as well a... used-silical capillary columns containing heptakis(2、3、6-tri-o-pentyl)-β-cyclodextrinand dibenzo-18-crown-6 were prepared.By studying the selectivity of mixed stationary phases forsome solute pairs.as well as comparing with the heptakis(2.3、6-tri-O-pentyl)-β-cyclodextrin and thedibenzo-18-crown-6 used as individual stationary phase、the synergistic effects were observed.These effects were affected by the column temperature.mixed ratio and linear velocity of carrier gas. 展开更多
关键词 Gas chromatography mixed stationary phase synergistic effect heptakis(2.3.6-tri-o-pentyl)-β-cyclodextrin dibenzo-18-CROWN-6
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Comparative Study on Thermodynamic Properties and Stabilities of Polychloro-phenazines and Polychlorinated Dibenzo-p-dioxin 被引量:2
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作者 韦晓燕 高树梅 +3 位作者 刘辉 王遵尧 王汇 王连生 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第4期397-404,共8页
The thermodynamic properties and molecular volumes (Vm) of 76 polychlorophenazines (PCPZs) have been calculated at the B3LYP/6-31G^* level by using density functional theory. The isodesmic reactions were designed... The thermodynamic properties and molecular volumes (Vm) of 76 polychlorophenazines (PCPZs) have been calculated at the B3LYP/6-31G^* level by using density functional theory. The isodesmic reactions were designed to calculate standard enthalpy of formation (△fH^θ) and standard free energy of formation (△fG^θ) of PCPZ congeners. According to the relative magnitude of their △fG^θ, the order of relative stability of PCPZ congeners was theoretically proposed. Comparing the results with those of polychlorinated dibenzo-p-dioxin (PCDD) isomers, it was found that S^θ, △fH^θ, △fG^θ, Vm and the order of relative stability of PCPZ congeners were quite similar to those of PCDDs. 展开更多
关键词 polychlorophenazines polyehlorinated dibenzo-p-dioxin density functional theory relative stability
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Synthesis and Crystal Structure of 3,3'-Dimethyl-dibenzo-18-crown-6 被引量:1
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作者 NIU Mei-Ju DOU Jian-Min WANG Da-Qi LI Da-Cheng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第6期757-760,共4页
3,3′-Dimethyl-dibenzo-18-crown-6 was synthesized and characterized by elemental analysis, FT-IR, ^1H NMR, UV, MS spectra and X-ray single-crystal diffraction. It belongs to orthorhombic, space group Pna21 with a = 8.... 3,3′-Dimethyl-dibenzo-18-crown-6 was synthesized and characterized by elemental analysis, FT-IR, ^1H NMR, UV, MS spectra and X-ray single-crystal diffraction. It belongs to orthorhombic, space group Pna21 with a = 8.0790(18), b = 16.780(4), c = 15.222(3) .A, Z= 4, V= 2063.6(8) A3 Dc = 1.250 g/cm^3,μ = 0.090 mm^-1, F(000) = 832, R = 0.0474 and wR = 0.1103. According to structural analysis, the title compound possesses a boat-like configuration. 展开更多
关键词 crown ether 3 3'-dimethyl-dibenzo-18-crown-6 SYNTHESIS crystal structure
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Application of Dibenzo-21-Crown-7 for Cesium Extraction from Geothermal Water
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作者 LIU Mingming GAO Daolin +2 位作者 ZHANG Nan YU Xiaoping DENG Tianlong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期350-351,共2页
Cesium as a kind of alkali metals has widely been used in catalysis,medicine,biology,magnetic fluid power and other high-tech fields(Liao and Yang,2012;Cao et al.,2011;Wang et al.,2011).Although there was abundant of
关键词 INTERMEDIATE dibenzo-21-crown-7 SYNTHESIS EXTRACTION
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Chromatographic separation of Be(Ⅱ) from Mg(Ⅱ), Ca(Ⅱ), Sr(Ⅱ) and Ba(Ⅱ) using poly[dibenzo-18-crown-6] and L-arginine
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作者 Sandip R. Sabale Baburao S. Mohite 《Journal of Chemistry and Chemical Engineering》 2009年第6期37-43,共7页
A simple and selective method for the separation of Be(Ⅱ) was developed using poly[dibenzo-18-crown-6] as a stationary phase in column chromatography. The study was carried out in L-arginine medium. 1.0-8.0 M HCl a... A simple and selective method for the separation of Be(Ⅱ) was developed using poly[dibenzo-18-crown-6] as a stationary phase in column chromatography. The study was carried out in L-arginine medium. 1.0-8.0 M HCl and CH3COOH, 0.5-8.0 M HBr, HClO4 and H2SO4, 0.2-1.0 M EDTA and 0.02-0.12 M ammonium oxalate were found to be an efficient eluents for Be(Ⅱ). The capacity of polymer was 0.554-0.01 mmol/g of crown polymer. The tolerance limit of various cations and anions were reported. Be(Ⅱ) was quantitatively separated from Mg(Ⅱ), Ca(Ⅱ), Sr(Ⅱ) and Ba(Ⅱ). The selective separation of Be(Ⅱ) was possible from multicomponent mixtures. The method was extended to determine Be(Ⅱ) from geological samples. Method was simple, rapid and selective having good reproducibility (approximately4-2%). 展开更多
关键词 Be(Ⅱ) poly[dibenzo-18-crown-6] L-ARGININE SEPARATION column chromatography
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Polychlorinated Dibenzofurans and Dibenzo-p-Dioxin in Tree Bark from an Industrialized Area: What the 2,3,7,8-Cl Substituted Congeners Tell Us, and What Is Missing
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作者 Mark H. Hermanson Glenn W. Johnson 《Journal of Environmental Protection》 2016年第3期351-357,共7页
We analyzed polychlorinated dibenzofurans (PCDF) and dibenzo-p-dioxins (PCDD) in 27 tree bark samples from the industrialized area near Sauget, Illinois, USA. The trees were located within 4 km of the W. G. Krummrich ... We analyzed polychlorinated dibenzofurans (PCDF) and dibenzo-p-dioxins (PCDD) in 27 tree bark samples from the industrialized area near Sauget, Illinois, USA. The trees were located within 4 km of the W. G. Krummrich (WGK) plant, the oldest and largest chemical plant in Sauget, with 24 of 27 samples collected from residential areas. The percent of total PCDF or PCDD profiles of ten 2,3,7,8- Cl substituted PCDF and seven PCDD congeners is homogeneous: 90% of the variance among the samples is explained by 3 eigenvalues in a principal components analysis. The homogeneity of the data suggests that samples were affected by similar types of sources which may have been influenced by electric power generation, chemical waste incineration, and large-scale thermal production of chlorinated chemicals. Quantitatively, the 2,3,7,8-Cl substituted congener analysis does not account for 90% of the concentration of tetra- and penta-Cl homologues and 80% of hexa-Cl and 50% of hepta-Cl homologues. The World Health Organization stated during establishment of toxic equivalence factors (TEF, 2005 version) that calculation of toxic equivalents (TEQs) is not suitable for abiotic matrices, such as tree bark, which are not involved in human exposures. Our results show that the non-2,3,7,8-Cl substituted congeners have high concentrations and should be included in analysis. 展开更多
关键词 Tree Bark Polychlorinated Dibenzofurans Polychlorinated dibenzo-p-Dioxins Principal Components Analysis
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EXAMINATION OF POLYCHLORINATED DIBENZO-P-DIOXINS AND POLYCHLORINATED DIBENZOFURANS INTO PROCESS WATER OF KRAFT PULP BLEACHING MILL FROM ASPECT OF ENVIRONMENTAL WATER QUALITY
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作者 Hiroshi Ohi Tomoya Yokoyama Keiichi Nakamata 《天津科技大学学报》 CAS 2004年第A02期156-161,共6页
Process water of a pulp mill with kraft cooking, oxygen delignification and chlorine bleaching or chlorine dioxide (ECF) bleaching was examined from an aspect of a new level for environmental water quality in Japan. A... Process water of a pulp mill with kraft cooking, oxygen delignification and chlorine bleaching or chlorine dioxide (ECF) bleaching was examined from an aspect of a new level for environmental water quality in Japan. According to the new level, a concentration of dioxins consisting of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar polychlorinated biphenyls (PCBs) in environmental water is restricted to less than 1 pg- TEQ/L. We clarified that the 2,3,7,8-tetrachlorodibenzofuran (TCDF) concentrations were 0.5 pg/L or less. In addition, a main source of 1,3,6,8- and 1,3,7,9-tetrachlorodibenzo-p-dioxins in the process water seemed to be an agrochemical in water supplied from a river. 展开更多
关键词 多氯二苯并二啞英 牛皮纸纸浆 漂白 二氧化氯 环境水质量 环境标准
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磺化炭催化苯甲酸二甘醇酯化反应制备二甘醇二苯甲酸酯 被引量:1
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作者 徐伟斌 韩亚彤 +2 位作者 司玉玺 成有为 王丽军 《化学反应工程与工艺》 CAS 2024年第1期28-34,共7页
从精对苯二甲酸(PTA)氧化残渣回收苯甲酸(BA)制备环保增塑剂二甘醇二苯甲酸酯(DEDB),用于替代邻苯二甲酸酯类增塑剂的研究具有重要意义。本工作通过磺化将—SO3H基团负载到活性炭(AC)表面,成功制备了磺化炭(SAC)催化剂。并以BA和二甘醇(... 从精对苯二甲酸(PTA)氧化残渣回收苯甲酸(BA)制备环保增塑剂二甘醇二苯甲酸酯(DEDB),用于替代邻苯二甲酸酯类增塑剂的研究具有重要意义。本工作通过磺化将—SO3H基团负载到活性炭(AC)表面,成功制备了磺化炭(SAC)催化剂。并以BA和二甘醇(DEG)为原料,SAC为催化剂,考察了催化剂浓度、反应温度、酸醇物质的量比[n(BA):n(DEG)]、带水剂甲苯用量对直接酯化合成DEDB的影响。结果表明:原料n(BA):n(DEG)为2.2、催化剂与原料BA的质量比为2%、带水剂甲苯与原料BA的质量比为14%、反应温度为210℃为最佳反应工艺条件,此条件下BA的转化率为90.1%,DEDB的收率为82.6%。 展开更多
关键词 磺化炭催化剂 苯甲酸 二甘醇二苯甲酸酯
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某生活垃圾焚烧厂排放废气、飞灰、环境空气和土壤中各二噁英类单体分布特征 被引量:1
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作者 毛慧 张宗祥 于建飞 《环境化学》 CAS CSCD 北大核心 2024年第8期2758-2768,共11页
以某生活垃圾焚烧企业为研究对象,研究其烟道气废气、焚烧飞灰、企业周边环境空气和土壤中二噁英的水平和各二噁英类单体指纹分布特征,研究结果表明,废气中的二噁英呈现出冬季稍高于夏季的排放特征,呋喃对总∑TEQ的贡献率范围为72%-90%... 以某生活垃圾焚烧企业为研究对象,研究其烟道气废气、焚烧飞灰、企业周边环境空气和土壤中二噁英的水平和各二噁英类单体指纹分布特征,研究结果表明,废气中的二噁英呈现出冬季稍高于夏季的排放特征,呋喃对总∑TEQ的贡献率范围为72%-90%.飞灰作为垃圾焚烧中二噁英的主要捕集途径,TEQ浓度季度变化比废气更加明显,呋喃对总∑TEQ的贡献率范围为74%-81%.环境空气和土壤中二噁英的季度分布特征与废气、飞灰的分布特征一致,且主导风向土壤中二噁英的TEQ浓度明显高于次主导风向.环境空气单体指标中呋喃对总∑TEQ的贡献率与废气和飞灰规律一致,说明该区域环境空气中的二噁英与企业排放废气中的二噁英具有同源性.与废气、飞灰和环境空气相比,土壤中呋喃与二噁英的比值和呋喃对总∑TEQ的贡献率存在差异,说明土壤中的二噁英并非单一来源于企业排放废气.废气、飞灰、企业周边环境空气和土壤中的17种PCDD/Fs单体中含量最丰富的是O8CDD,PCDDs的浓度随着取代氯原子个数的增加而增大.17种PCDD/Fs单体中对毒性当量贡献最大的单体是2,3,4,7,8-P5CDF.2,3,7,8-T4CDD是引起废气中二噁英排放呈现出冬季稍高于夏季的特征污染因子,需要重点关注. 展开更多
关键词 生活垃圾焚烧企业 二噁英 飞灰 环境空气 土壤.
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Polychlorinated dibenzo-p-dioxins and dibenzofurans in different tissues of the cormorants (Phalacrocorax carbo) from Dongting Lake,China 被引量:4
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作者 Lirong Gaol Minghui Zheng Bing Zhang Wenbin Liu Ke Xiao Guijin Su Qinghua Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第10期1709-1713,共5页
Tissue distribution provides important information regarding the pharmacokinetic behavior of pollutants and is invaluable when analyzing the risk posed to avian species by the exposure to such kind of pollutants. In t... Tissue distribution provides important information regarding the pharmacokinetic behavior of pollutants and is invaluable when analyzing the risk posed to avian species by the exposure to such kind of pollutants. In this study, concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were determined in muscle, liver, spleen, kidney, stomach, gall bladder, skin, heart, pancreas, intestine and lung tissue extracts of cormorants collected from Dongting Lake, China. Tissue distribution results showed preferential accumulation of PCDD/Fs in both liver and skin. The total concentration of PCDD/Fs ranged from 421 to 5696 pg/g lipid weight. Octachlorinated dibenzo-p-dioxin (OCDD) was the predominant congener in all tissues and contributed between 31% and 82% to all 17 PCDD/Fs in different tissues. The liver/muscle ratios progressively increased with the degree of chlorination of PCDDs, except for OCDD. The relative toxic potential of PCDDs and PCDFs in tissues were calculated using the World Health Organization (WHO) Toxic Equivalency Factors (TEFs) for birds. The concentrations of WHO-toxic equivalent in different tissues ranged between 14.8 and 2021 pg/g lipid weight. These results indicated PCDD/Fs may have been bio-accumulated in cormorant via food-web. Furthermore, when compared with studies reported in the literatures, the PCDD/Fs levels in the cormorant collected from Dongting Lake were still relatively high. 展开更多
关键词 polychlorinated dibenzo-p-dioxins DIBENZOFURANS CORMORANT Dongting Lake DISTRIBUTION TISSUE
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环保增塑剂二甘醇二苯甲酸酯合成催化剂研究进展
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作者 李俊华 苗伟涛 《河南化工》 CAS 2024年第10期31-33,共3页
对环保增塑剂二甘醇二苯甲酸酯合成催化剂的研究进展进行了论述,重点列举了甲苯磺酸、杂多酸、固体超强酸、酸性离子液体、钛酸酯、氧化铝、氧化亚锡、微波辐射催化剂与催化反应条件、产品收率、污染程度、产品质量的关联情况,提出了二... 对环保增塑剂二甘醇二苯甲酸酯合成催化剂的研究进展进行了论述,重点列举了甲苯磺酸、杂多酸、固体超强酸、酸性离子液体、钛酸酯、氧化铝、氧化亚锡、微波辐射催化剂与催化反应条件、产品收率、污染程度、产品质量的关联情况,提出了二甘醇二苯甲酸酯合成催化剂研究方向。 展开更多
关键词 环保增塑剂 二甘醇二苯甲酸酯 合成 催化剂
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半挥发性有机污染场地的高级氧化修复技术
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作者 朱广森 霍云剑 纪元 《化工管理》 2024年第17期61-64,共4页
文章以上海市某污染场地为案例,针对污染因子为苯并[a]芘、二苯并[a,h]蒽的半挥发性有机污染场地类型,采用以亚铁激活过硫酸盐类氧化剂的高级氧化修复技术手段,通过实验室小试和中试试验确定工程应用硫酸亚铁和过硫酸钠的最佳药剂投加比... 文章以上海市某污染场地为案例,针对污染因子为苯并[a]芘、二苯并[a,h]蒽的半挥发性有机污染场地类型,采用以亚铁激活过硫酸盐类氧化剂的高级氧化修复技术手段,通过实验室小试和中试试验确定工程应用硫酸亚铁和过硫酸钠的最佳药剂投加比例,对污染场地中清挖出有机污染土壤进行筛分破碎、调节含水率、添加氧化药剂进行修复。修复后的土壤经过检测均达到修复要求,且整个修复过程未对地块的土壤和地下水造成二次污染。 展开更多
关键词 有机污染物 高级氧化 苯并[A]芘 二苯并[a h]蒽 土壤修复
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Aspects of formation and degradation of polychlorinated dibenzo-p-dioxins and dibenzofurans
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作者 Minghui Zheng Pengyan Liu +1 位作者 Zhicheng Bao Xiaobai Xu 《Chinese Science Bulletin》 SCIE EI CAS 1999年第14期1249-1257,共9页
The research progress on the mechanisms of formation and degradation of polychlorinated dibenzo-p-dioxins ( PCDDs ) and dibenzofurans ( PCDFs ) is reviewed. The primary sources of PCDD/Fs are chemical, thermal, photoc... The research progress on the mechanisms of formation and degradation of polychlorinated dibenzo-p-dioxins ( PCDDs ) and dibenzofurans ( PCDFs ) is reviewed. The primary sources of PCDD/Fs are chemical, thermal, photochemical and enzymatic reactions. Most of the thermal sources result in emissions into air. The studies on the photodegradation and biodegradation offer promise for destruction of PCDD/Fs in environment. 展开更多
关键词 POLYCHLORINATED dibenzo-P-DIOXINS POLYCHLORINATED DIBENZOFURANS mechanism FORMATION degradation.
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Synthesis and crystal structure of a new polpouclear complex with a monomer of (3,4,9,10-dibenzo-1, 12-diaza-5, 8-dioxacyclopentadecane)-copper(Ⅱ) (μ-Cl)_2 zinc(Ⅱ) chloride
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作者 GOU, Shao-Hua XU, Zheng +2 位作者 YOU, Xiao-Zeng ZHENG, Pei-Ju DONG, Jun Coordination Chemistry Institute, Nanjing University, Nanjing 210008 Center of Analysis and Measurement, Fudan University, Shanghai 200433 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1992年第3期232-236,共0页
A polynuclear complex containing a monomer of Cu(Ⅱ)-Zn(Ⅱ) heterobinuclear unit was synthesized and characterized by IR spectra and magnetic moment. The crystal and molecular structure of the complex, CuZnC_(19)H_(24... A polynuclear complex containing a monomer of Cu(Ⅱ)-Zn(Ⅱ) heterobinuclear unit was synthesized and characterized by IR spectra and magnetic moment. The crystal and molecular structure of the complex, CuZnC_(19)H_(24)Cl_4N_2O_2, was determined by X-ray diffraction, it crystallized in monoclinic, P2_1 / m, a = 8.812 (2), b = 15.972(3), c = 8.831(1) A, β = 114.33(1)°, V = 1132.4A^3, Z=2, D_c= 1.710 g / cm^3, λ(Mo K_α) = 0.71073A, μ = 25.227 cm^(-1), R = 0.051. R_w = 0.063 for 1130 ob- served reflections with I> 3σ(I) . The coordinated octahedra of Cu(Ⅱ) and tetrahedra of Zn(Ⅱ) via bridging Cl atoms form a single chain polynuclear complex. The Cu, Zn and bridging Cl atoms are located on the crystallographic symmetry plane m which is perpendicular to 2N and 2O donor plane. 展开更多
关键词 Synthesis and crystal structure of a new polpouclear complex with a monomer of CHLORIDE copper diaza-5 dibenzo-1 dioxacyclopentadecane ZINC CL
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冠醚交联聚砜膜的制备及其锂镁分离性能 被引量:1
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作者 严峰 冯明娜 +2 位作者 郭宗华 王明霞 方洪波 《天津工业大学学报》 CAS 北大核心 2023年第2期13-21,共9页
为解决冠醚化合物用于传统液-液萃取分离锂镁时冠醚易于流失的问题,以二氨基二苯并14-冠-4(DAB14C4)和氯甲基聚砜(CMPSf)为原料,采用反应-相转化一锅法制备冠醚交联聚砜膜(DAB14C4-cr-PSf)。考察交联反应温度、反应时间、热处理时间及... 为解决冠醚化合物用于传统液-液萃取分离锂镁时冠醚易于流失的问题,以二氨基二苯并14-冠-4(DAB14C4)和氯甲基聚砜(CMPSf)为原料,采用反应-相转化一锅法制备冠醚交联聚砜膜(DAB14C4-cr-PSf)。考察交联反应温度、反应时间、热处理时间及反应液中冠醚浓度等因素对DAB14C4-cr-PSf膜中冠醚固载量的影响,探究DAB14C4-cr-PSf膜对Li^(+)的选择吸附性及锂镁分离性能。结果表明:当交联反应时间为8 h、反应温度为45℃、70℃热水处理1.5 h、冠醚质量分数为0.5%时,DAB14C4-cr-PSf膜达到最佳冠醚固载量(0.190 mmol/g);在Flow-through模式下,DAB14C4-cr-PSf对Li^(+)的吸附量(QLi)及锂镁分离因子(α)分别为8.55 mg/g和5.96;当有K^(+)、Na^(+)等离子共存时,DAB14C4-cr-PSf膜对于Li^(+)/K^(+)、Li^(+)/Na^(+)和Li^(+)/Mg^(2+)的分离因子分别为11.41、10.50和5.69,表明DAB14C4-cr-PSf膜对Li^(+)具有选择性吸附能力,且Li^(+)/Mg^(2+)的分离性能几乎不受干扰离子影响。 展开更多
关键词 冠醚交联聚砜膜 二氨基二苯并14-冠-4 多孔膜 锂离子 选择性吸附
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2,4-戊二醇二苯甲酸酯用量对新型载体催化剂性质和性能的影响
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作者 周俊领 凌永泰 李威莅 《石油化工》 CAS CSCD 北大核心 2023年第5期666-671,共6页
使用一种新型载体通过不同用量的2,4-戊二醇二苯甲酸酯(PDDB)制备了四种催化剂。利用FTIR,XPS,XRD以及元素分析和丙烯聚合评价等方法研究了不同PDDB用量对催化剂的组成、基团间相互作用、晶体结构和催化剂活性的影响。实验结果表明,随着... 使用一种新型载体通过不同用量的2,4-戊二醇二苯甲酸酯(PDDB)制备了四种催化剂。利用FTIR,XPS,XRD以及元素分析和丙烯聚合评价等方法研究了不同PDDB用量对催化剂的组成、基团间相互作用、晶体结构和催化剂活性的影响。实验结果表明,随着PDDB用量增加,催化剂中钛含量从7.4%(w)降至2.7%(w)后又增至3.6%(w);PDDB中羰基与基体存在多种相互作用,红外吸收峰位置向低波数偏移且峰形变宽;PDDB用量影响催化剂的晶体结构和钛元素的表面分布;催化剂性能也受PDDB用量的影响,当PDDB用量为7.6 mmol时催化剂的活性最好。 展开更多
关键词 载体 氯化镁 催化剂 聚丙烯 2 4-戊二醇二苯甲酸酯
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冠醚-咪唑型铁基超分子材料的合成、结构及电学性能
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作者 努尔曼·依斯马依力 胡宏志 +2 位作者 王娜 刘洋 刘尊奇 《新疆农业大学学报》 CAS 2023年第5期399-408,共10页
以咪唑、三氯化铁和二苯并-18-冠醚-6为原料,通过自然蒸发法在乙腈溶剂中获得了一种有机-无机杂化超分子材料(C_(3)H_(5)N_(2))^(+)(DB-18-Crown-6)(FeCl_(4))^(-)。通过红外光谱、单晶X-射线衍射、粉末X-射线衍射、热重分析、介电常数... 以咪唑、三氯化铁和二苯并-18-冠醚-6为原料,通过自然蒸发法在乙腈溶剂中获得了一种有机-无机杂化超分子材料(C_(3)H_(5)N_(2))^(+)(DB-18-Crown-6)(FeCl_(4))^(-)。通过红外光谱、单晶X-射线衍射、粉末X-射线衍射、热重分析、介电常数和电化学等对其结构和性能进行表征。结果显示,(C_(3)H_(5)N_(2))^(+)(DB-18-Crown-6)(FeCl_(4))^(-)在低温(100 K)和室温(293 K)的空间群为Ia,属于单斜晶系,在空间结构内超分子阳离子(C_(3)H_(5)N_(2))^(+)(DB-18-Crown-6)与阴离子(FeCl_(4))^(-)以N-H…O、C-H…O、C-H…Cl等氢键相互作用形成二维网状超分子结构。介电测试显示(C_(3)H_(5)N_(2))^(+)(DB-18-Crown-6)(FeCl_(4))^(-)在升温和降温的过程中均在160~200 K和220~260 K产生两个阶梯型介电异常峰,其循环伏安测试表明(C_(3)H_(5)N_(2))^(+)(DB-18-Crown-6)(FeCl_(4))^(-)具有明显的电子转移性能,显示(C_(3)H_(5)N_(2))^(+)(DB-18-Crown-6)(FeCl_(4))^(-)是一种新型的介电异常及电化学性能材料。 展开更多
关键词 二苯并-18-冠醚-6 咪唑 超分子材料 氢键 阶梯型介电异常
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