期刊文献+

二次检索

题名
关键词
文摘
作者
第一作者
机构
刊名
分类号
参考文献
作者简介
基金资助
栏目信息
共找到1,702篇文章
< 1 2 86 >
每页显示 20 50 100
Impact of Cr(Ⅲ) complexation with organic acid on its adsorption in silts and fine sands
1
作者 Zi-xuan Zhang Lin Wu +4 位作者 Xiang-ke Kong Hui Li Le Song Ping Wang Yan-yan Wang 《Journal of Groundwater Science and Engineering》 2024年第4期347-359,共13页
Trivalent chromium(Cr(Ⅲ))can form stable soluble complexes with organic components,altering its adsorption properties in the water-soil environment.This increases the risk of Cr(Ⅲ)migrating to deeper soils and trans... Trivalent chromium(Cr(Ⅲ))can form stable soluble complexes with organic components,altering its adsorption properties in the water-soil environment.This increases the risk of Cr(Ⅲ)migrating to deeper soils and transforming into toxic Cr(VI)due to the presence of manganese oxides in sediments.In this study,Citric Acid(CA)was selected as a representative organic ligand to prepare and characterize Cr(III)-CA complexes.The characteristics,mechanisms and environmental factors influencing the adsorption of Cr(Ⅲ)-CA on porous media(silts and fine sands)were investigated in the study.The results show that Cr(Ⅲ)coordinates with CA at a 1:1 molar ratio,forming stable and soluble Cr(Ⅲ)-CA complexes.Compared to Cr(III)ions,the equilibrium adsorption capacity of Cr(Ⅲ)-CA is an order of magnitude lower in silts and fine sands.The adsorption of Cr(Ⅲ)-CA in silts and fine sands is dominated by chemical adsorption of monolayers,following the pseudo-second-order kinetic equation and the Langmuir isotherm adsorption model.Varying contents of clay minerals and iron-aluminum oxides prove to be the main causes of differences in adsorption capacity of Cr(Ⅲ)-CA in silts and fine sands.Changes in solution pH affect the adsorption rate and capacity of Cr(Ⅲ)-CA by altering its ionic form.The adsorption process is irreversible and only minimally influenced by ionic strength,suggesting that inner-sphere complexation serves as the dominant Cr(Ⅲ)-CA adsorption mechanism. 展开更多
关键词 cr() cr()-citric acid Porous media ADSORPTION Inner-sphere complexation
下载PDF
以箬叶“炭”究Cr(Ⅲ)和Cr(Ⅵ)的检测与吸附综合实验
2
作者 张蕾 肖长生 +1 位作者 苏明伟 张洪权 《湖北第二师范学院学报》 2024年第8期20-26,共7页
本文以“科教融合”为导向,以湖北鹤峰的箬叶为原料,制备生物质炭和碳量子点并进行基本表征,以生物质炭吸附Cr(Ⅲ)和Cr(Ⅵ),以荧光淬灭法检测Cr(Ⅲ)和Cr(Ⅵ),吸附和检测过程绿色环保。结果表明生物质炭吸附Cr(Ⅲ)的吸附符合颗粒内扩散模... 本文以“科教融合”为导向,以湖北鹤峰的箬叶为原料,制备生物质炭和碳量子点并进行基本表征,以生物质炭吸附Cr(Ⅲ)和Cr(Ⅵ),以荧光淬灭法检测Cr(Ⅲ)和Cr(Ⅵ),吸附和检测过程绿色环保。结果表明生物质炭吸附Cr(Ⅲ)的吸附符合颗粒内扩散模型,吸附Cr(Ⅵ)符合准二级动力学模型,二者均为自发吸热过程。作为本科生综合教学实验,本实验不仅涉及多种无机化学、分析化学、物理化学、仪器分析的理论知识,还包含了制备、表征、数据处理、吸附机制分析等重要环节,同时融入了文化自信、地域文化和绿色化学等课程思政理念。该创新实验教学时长约为24小时,适合用于综合化学实验教学,实现了基础化学理论在实践中的有效应用,提升了化学专业学生的综合能力。 展开更多
关键词 箬叶 生物质炭 碳量子点 cr()和cr(Ⅵ) 检测与吸附
下载PDF
蛋白-多糖-Cr(Ⅲ)络合物的形成及其脱铬机制 被引量:1
3
作者 马宏瑞 杜佳怡 +2 位作者 党靖雯 郝永永 朱超 《皮革科学与工程》 CAS 北大核心 2024年第6期1-8,共8页
选取海藻酸钠(SA)、牛血清白蛋白(BSA)模拟制革废水处理过程中的多糖和蛋白,探讨了多糖、蛋白与Cr(Ⅲ)形成的不同络合物的特性及其稳定性。研究发现,SA和BSA与Cr(Ⅲ)结合后,所形成的络合物相对分子质量明显小于单独的配体,且主要通过配... 选取海藻酸钠(SA)、牛血清白蛋白(BSA)模拟制革废水处理过程中的多糖和蛋白,探讨了多糖、蛋白与Cr(Ⅲ)形成的不同络合物的特性及其稳定性。研究发现,SA和BSA与Cr(Ⅲ)结合后,所形成的络合物相对分子质量明显小于单独的配体,且主要通过配体分子内配位形成Cr(Ⅲ)络合物,络合物的零电荷点向pH中性偏移,增加了中和沉淀、絮凝沉淀的效果,但总铬去除率最高为85.62%。通过超声预处理与重捕剂协同絮凝剂的作用,络合物铬去除率可提高至98%以上,且不受pH的影响。此研究结果为非中性条件下铬的深度去除提供了理论和实践依据。 展开更多
关键词 制革废水 cr()络合物 絮凝沉淀 超声预处理 海藻酸钠 牛血清白蛋白
下载PDF
多参数MRI联合螺旋CT预测ⅢCr期宫颈癌同步放化疗后复发的临床价值 被引量:2
4
作者 兰姗 陈思 《中国CT和MRI杂志》 2024年第2期135-138,共4页
目的研究多参数MRI联合SCT预测ⅢCr期宫颈癌同步放疗(CCRT)后复发的临床价值。方法回顾性分析医院2018.01~2020.01间70例行同步放化疗后出现复发的ⅢCr期宫颈癌患者(复发组)以及66例无复发者的多参数MRI以及SCT检查资料,以临床诊断作为... 目的研究多参数MRI联合SCT预测ⅢCr期宫颈癌同步放疗(CCRT)后复发的临床价值。方法回顾性分析医院2018.01~2020.01间70例行同步放化疗后出现复发的ⅢCr期宫颈癌患者(复发组)以及66例无复发者的多参数MRI以及SCT检查资料,以临床诊断作为“金标准”,采用McNemar检验,分别计算多参数MRI以及SCT在诊断宫颈癌复发中的灵敏度、特异度及准确度,并绘制ROC曲线,分析多参数MRI联合SCT诊断宫颈癌复发的价值。结果经局部穿刺以及随访发现,共70例患者被证实为宫颈癌复发,66例患者为非复发,其中复发组患者MRI检查参数ADC_(min)、ADC_(max)、ADC_(mean)、K^(trans)、K_(ep)以及V_(e)水平显著低于对照组(P<0.05);以临床诊断作为“金标准”,检验发现,多参数MRI在诊断宫颈癌复发中的灵敏度及特异度分别为85.71%、89.39%。SCT在诊断宫颈癌复发中的灵敏度及特异度分别为55.71%、81.82%。绘制ROC曲线证实多参数MRI联合SCT在预测ⅢCr期宫颈癌同步放化疗后复发中的的AUC=0.941,95%CI(0.895~0.987),灵敏度及特异度分别为94.30%与93.90%。结论多参数MRI在诊断ⅢCr期宫颈癌CCRT后复发中的价值高于SCT,但两者联合使用能有效提高宫颈癌复发的临床诊断效果。 展开更多
关键词 多参数磁共振 螺旋CT cr期宫颈癌 同步放化疗 复发
下载PDF
磁性介孔碳负载纳米零价铁的制备及其去除高盐废水中Cr(Ⅲ)有机配合物 被引量:1
5
作者 张元培 王家宏 +1 位作者 黄金明 胡智 《无机化学学报》 SCIE CAS CSCD 北大核心 2024年第9期1731-1742,共12页
采用液相还原法制备了磁性介孔碳(Fe_(3)O_(4)@C)负载纳米零价铁(nano zero-valent iron,nZVI)复合材料(Fe_(3)O_(4)@C-nZVI),并将其用于高盐水中Cr(Ⅲ)-EDTA(EDTA:乙二胺四乙酸)的去除。扫描电镜、透射电镜、X射线衍射等表征表明nZVI... 采用液相还原法制备了磁性介孔碳(Fe_(3)O_(4)@C)负载纳米零价铁(nano zero-valent iron,nZVI)复合材料(Fe_(3)O_(4)@C-nZVI),并将其用于高盐水中Cr(Ⅲ)-EDTA(EDTA:乙二胺四乙酸)的去除。扫描电镜、透射电镜、X射线衍射等表征表明nZVI成功负载且分散良好,可磁性分离,在碳层保护下nZVI稳定性强,有利于材料的重复利用。nZVI的加人大大提高了Fe_(3)O_(4)@C-nZVI对Cr(Ⅲ)-EDTA的吸附能力,在pH=4.0、反应温度为25℃时,Fe_(3)O_(4)@C-nZVI对Cr(Ⅲ)-EDTA的最大吸附量为10.24 mg·g^(-1),显著高于Fe_(3)O_(4)@C(4.31 mg·g^(-1))。吸附Cr(Ⅲ)-EDTA的过程更符合Langmuir模型和准二级动力学模型。Fe_(3)O_(4)@C-nZVI对Cr(Ⅲ)-EDTA的吸附能力随着溶液pH值的增加先增加后减小;低浓度络合剂(EDTA、柠檬酸)会促进Cr(Ⅲ)-EDTA的吸附,而络合剂浓度增加时则表现为抑制;高浓度阳离子(Na^(+)、K^(+)、Ca^(2+))会促进Cr(Ⅲ)-EDTA的吸附。Fe_(3)O_(4)@C-nZVI在盐和络合剂环境中对Cr(Ⅲ)-EDTA仍表现出显著的吸附效果。经过3次再生循环后,Fe_(3)O_(4)@C-nZVI对Cr(Ⅲ)-EDTA的吸附量达6.90 mg·g^(-1)。X射线光电子能谱分析表明,Fe_(3)O_(4)@C-nZVI通过表面Fe(Ⅲ)与Cr(Ⅲ)-EDTA之间的配位作用形成FedO-EDTA-Cr(Ⅲ)配合物从而将Cr(Ⅲ)-EDTA去除,随后通过离子置换作用将Cr(Ⅲ)置换出来,置换出的Cr(Ⅲ)会与表面氧化铁共沉淀为Cr_(x)Fe_(1-x)(OH)_(3),进而沉积在nZVI表面被去除。 展开更多
关键词 磁性介孔碳 纳米零价铁 cr() 高盐废水 吸附机制
下载PDF
Cr(Ⅲ)对锰氧化菌P.putida MnB1活性及功能的影响规律与机制
6
作者 尹元雪 赵雨溪 +1 位作者 孙群群 童曼 《地质科技通报》 CAS CSCD 北大核心 2024年第1期298-305,共8页
三价铬(Cr(Ⅲ))与锰氧化菌在环境中通常伴同存在,锰氧化菌介导生成的锰氧化物是Cr(Ⅲ)的主要天然氧化剂,探究Cr(Ⅲ)对锰氧化菌活性和功能的影响对于阐明环境中的锰循环和铬的迁移转化行为具有重要意义。以锰氧化模式菌Pseudomonas putid... 三价铬(Cr(Ⅲ))与锰氧化菌在环境中通常伴同存在,锰氧化菌介导生成的锰氧化物是Cr(Ⅲ)的主要天然氧化剂,探究Cr(Ⅲ)对锰氧化菌活性和功能的影响对于阐明环境中的锰循环和铬的迁移转化行为具有重要意义。以锰氧化模式菌Pseudomonas putida MnB1为研究对象,通过批实验探究了Cr(Ⅲ)对MnB1活性与功能的影响及其机制。结果表明,Cr(Ⅲ)浓度高于0.05 mmol/L时会造成MnB1的显著死亡,且Cr(Ⅲ)浓度越高杀菌作用越显著,当Cr(Ⅲ)高于0.02 mmol/L时会推迟锰的生物氧化,当Cr(Ⅲ)浓度高于0.2 mmol/L时完全抑制锰的生物氧化。机制研究表明,Cr(Ⅲ)诱导产生的胞内活性氧和Cr(Ⅲ)颗粒引起的细胞膜通透性改变共同影响了MnB1的生长代谢和功能。研究结果为认识锰的生物地球化学循环和铬的迁移转化行为提供了新的理论依据。 展开更多
关键词 三价铬 锰氧化菌 活性氧 锰循环 铬污染
下载PDF
Investigation on Molecular and Crystal Structures of Metal Complexes with Aminopolycarboxylic Acids——Synthesis and Structure of K[In~Ⅲ(EDTA)(H_2O)]·2H_2O 被引量:2
7
作者 王君 陈冬松 +1 位作者 宋玉林 高敬群 《Rare Metals》 SCIE EI CAS CSCD 1998年第3期54-59,共6页
The title complex was synthesised and its molecular and crystal structures were determined by single crystal X ray reflection structure analysis. The crystal data are as follows: K[In Ⅲ(EDTA)(H 2O)]·2H 2O (... The title complex was synthesised and its molecular and crystal structures were determined by single crystal X ray reflection structure analysis. The crystal data are as follows: K[In Ⅲ(EDTA)(H 2O)]·2H 2O (EDTA=ethylene diamine N, N, N′, N′ tetraacetate), Monoclinic, C c space group, a=0.9096(2) nm,b=1.1996(2) nm, c =1.5144(3) nm, β =99.40(3)°, V =1.6302(6) 3, Z =3, D c=1.498 g·cm -3 , μ =1.325 mm -1 , F (000)=726, R =0.0320 and R W=0.0903 for 2315 observed independent reflections. The complex anion [In Ⅲ(EDTA)(H 2O)] - has a seven coordinate pseudo pentagonal bipyramidal (PB D 5h ) structure, in which the EDTA serves as a hexadentate ligand with two N atoms and four O atoms and one water molecule (H 2O) directly coordinated to the central metal ion In Ⅲ as a seventh ligand. 〓〓 展开更多
关键词 In Ethylenediaminetetraacetate (EDTA) complex Seven coordinate structures
下载PDF
Crystal Structure and Fluorescent Study of a Binuclear Europium(Ⅲ) Complex 被引量:3
8
作者 黄玲 刘荫秋 曾锡瑞 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第9期1126-1130,共5页
A novel binuclear Eu(Ⅲ) complex [Eu2(dpa dioxide)2(NO3)4(bpdioxide)-(EtOH)] (dpa dioxide = di-2-pyridylamine N,N'-dioxide, bpdioxide = 2,2'-bipyridine N,N'-dioxide) has been synthesized and it exhibits... A novel binuclear Eu(Ⅲ) complex [Eu2(dpa dioxide)2(NO3)4(bpdioxide)-(EtOH)] (dpa dioxide = di-2-pyridylamine N,N'-dioxide, bpdioxide = 2,2'-bipyridine N,N'-dioxide) has been synthesized and it exhibits strong and sharp fluorescent emission at 614 nm under UV radiation of 245 nm at room temperature. X-ray structural determination indicates two independent Eu(Ⅲ) ions in the structure with different EuO8N and EuOgN environments. The compound crystallizes in the triclinic system, space group P1, with a = 10.8089(7), b = 11.4670(8), c = 17.1440(12) A, α = 92.834(2), β = 93.854(3), γ = 95.433(2)°, Z = 2, Dc = 1.876 g/cm3, V= 2107.3(2) A3, F(000) = 1168.0, the final R = 0.032 and wR = 0.086 for 6331 observed reflections with I 〉 2σ(I). 展开更多
关键词 rare earth complex europium( LUMINESCENCE
下载PDF
Synthesis, Crystal Structure and Fluorescence Properties of a Terbium(Ⅲ) Complex with Biphenyl-2,3,3’,5’-tetracarboxylic Acid 被引量:2
9
作者 LI Rong-Fang ZHU Xin-Xin +2 位作者 LIU Xin-Fang FENG Xun Wang Li-Ya 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第6期985-990,共6页
A new terbium complex based on biphenyl-2,3,3’,5’-tetracarboxylic acid(H4bptc) has been synthesized, {[Tb(Hbptc)(H2O)4]×H2O}n(1). Its structure was determined by single-crystal X-ray diffraction analysi... A new terbium complex based on biphenyl-2,3,3’,5’-tetracarboxylic acid(H4bptc) has been synthesized, {[Tb(Hbptc)(H2O)4]×H2O}n(1). Its structure was determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR spectra and TG analyses. Title complex crystallizes in monoclinic, space group P21/n with a = 14.090(2), b = 8.0824(13), c = 15.5591(17) ?, V = 1775.4(5) ?3, Mr = 576.22, Dc = 2.156 g/cm3, μ(Mo Kα) = 4.059 mm-1, F(000) = 1128, Z = 4, the final R = 0.027 and w R = 0.0726 for 3296 observed reflections(I > 2σ(I)). Complex 1 exhibits a 2 D layer structure, and such layers are further united together into a three-dimensional supramolecular structure through π···π interaction and intricate hydrogen bonding. The fluorescence excitation and emission spectroscopy of 1 showed that H4 bptc is a kind of highly efficient sensitizer for terbium(Ⅲ) ion. The title complex also displays efficient ligand sensitized luminescence in the visible region with long lifetime of 2.02 ms in the solid state. 展开更多
关键词 terbium()complex π…πinteraction luminescence FLUORESCENCE lifetime
下载PDF
Hydrothermal Syntheses and Crystal Structures of Three Lanthanide(Ⅲ)Complexes Based on Carboxyl Derivatives of 1,10-Phenanthroline 被引量:5
10
作者 乔宇 尉兵 +5 位作者 李秀颖 车广波 刘春波 张兴晶 朱恩伟 刘凤 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第1期73-81,共9页
Three lanthanide(III) complexes [Ln(4-NCP)(1,4-BDC)]n·xn H2O(Ln = Pr(1), Sm(2), Nd(3). 4-HNCP = 2-(4-carboxyphenyl)imidazo(4,5-f)(1,10)phenanthroline, 1,4-H2 BDC = benzene-1,4-dicarboxylic acid... Three lanthanide(III) complexes [Ln(4-NCP)(1,4-BDC)]n·xn H2O(Ln = Pr(1), Sm(2), Nd(3). 4-HNCP = 2-(4-carboxyphenyl)imidazo(4,5-f)(1,10)phenanthroline, 1,4-H2 BDC = benzene-1,4-dicarboxylic acid) have been hydrothermally synthesized and characterized via elemental analysis, infrared spectrometry and single-crystal X-ray diffraction. Structural analyses revealed that complexes 1~3 possess similar porous three-dimensional frameworks with the point symbol {4^(12)·6~3}. Meanwhile, complexes 1~3 exhibit excellent thermal stabilities and complex 2 exhibits characteristic luminescent property. 展开更多
关键词 lanthanide( complex 2-(4-carboxyphenyl)imidazo(4 5-f)(1 10)phenanthroline benzene-1 4-dicarboxylic acid crystal structure luminescence
下载PDF
Synthesis and Crystal Structure of a Binuclear Gadolinium(Ⅲ) Complex Bridged by Cucurbit[6]uril 被引量:2
11
作者 Gui Ling ZHANG Zhi Yong WU +2 位作者 Yan Tuan LI Da Qi WANG Jian Min DOU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第1期93-96,共4页
A new cucurbit[6]uril bridsed binuclear complex {[Gd(H2O)6]2[Q6(H2O)]}C16·4H2O, where Q6 represents cucurbit[6]uril, has been synthesized and characterized by X-ray diffraction. The crystal structure shows th... A new cucurbit[6]uril bridsed binuclear complex {[Gd(H2O)6]2[Q6(H2O)]}C16·4H2O, where Q6 represents cucurbit[6]uril, has been synthesized and characterized by X-ray diffraction. The crystal structure shows that the complex has an extended cucurbit[6]uril-bridged structure consisting of two gadolinium(Ⅲ) ions, in which each gadolinium(Ⅲ) ion is coordinated with two neighboring carbonylic oxygen atoms of Q6 and six oxygen atoms of water molecules that leans toward one side of the portal. One disordered guest water molecule resides in the Q6 molecule cavity and occupies two different positions. Hydrogen bonds assemble the complcx to threedimensional supramolecular structure. 展开更多
关键词 uril binuclear gadolinium( complex crystal structure
下载PDF
Microwave assisted synthesis, spectroscopic, thermal, and antifungal studies of some lanthanide(Ⅲ) complexes with a heterocyclic bishydrazone 被引量:1
12
作者 K. Mohanan B. Sindhu Kumari G. Rijulal 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第1期16-21,共6页
A bishydrazone formed by the condensation of isatinmonohydrazone and salicylaldehyde reacted with lanthanide(Ⅲ) chloride to form complexes of the type [Ln(HISA)2Cl3], where, Ln=La(Ⅲ), Ce(Ⅲ), Pr(Ⅲ), Nd(... A bishydrazone formed by the condensation of isatinmonohydrazone and salicylaldehyde reacted with lanthanide(Ⅲ) chloride to form complexes of the type [Ln(HISA)2Cl3], where, Ln=La(Ⅲ), Ce(Ⅲ), Pr(Ⅲ), Nd(Ⅲ), Sm(Ⅲ), Eu(Ⅲ), or Gd(Ⅲ) and HISA= [(2-hydroxybenzaldehyde)-3-isatin]bishydrazone. Both reactions were carried out under microwave conditions. The ligand and the metal complexes were characterized on the basis of elemental analysis, molar conductance, magnetic susceptibility measurements, UV visible, infrared, far infrared, and proton NMR spectral data. The ligand acted as neutral tridentate, coordinating through the carbonyl oxygen, azomethine nitrogen, and phenolic oxygen without deprotonation. The ligand and lanthanum(Ⅲ) complex were subjected to X-ray diffraction studies. The X-ray diffraction pattern of ligand exhibited its crystalline nature and that of the lanthanum(Ⅲ) complex indicated its amorphous character. The thermal decomposition behaviour of the complex, [La(HISA)2Cl3], was examined in the temperature range of 40-800 ℃ using TG, DTG, and DTA. The ligand and the metal complexes were screened for their antifungal activities. 展开更多
关键词 microwave synthesis bishydrazones lanthanum( complex thermal decomposition antifungal activity rare earths
下载PDF
Crystal Structure of Binuclear Manganese(Ⅲ) Complex with Schiff-base Ligand,〔Mn_2(C_(22)H_(22)N_2O_2)_2(EtOH)_2 (bipy)〕(ClO_4)_2 被引量:1
13
作者 冯云龙 刘世雄 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1998年第2期125-128,共4页
The title complex, [Mn2L2(EtOH)2 (bipy )](ClO4)2 (L=N,N'-ethylenebis (1-phenyl-3-imino-1-butanonato), bipy = 4, 4'-bipyridine] crystallizes inmonoclinic system, space group P21/c with a= 12. 63O(5), b=13- 151 ... The title complex, [Mn2L2(EtOH)2 (bipy )](ClO4)2 (L=N,N'-ethylenebis (1-phenyl-3-imino-1-butanonato), bipy = 4, 4'-bipyridine] crystallizes inmonoclinic system, space group P21/c with a= 12. 63O(5), b=13- 151 (2), c=18. 3773001 reflections The two [MnL(EtOH)]+ units are joined by one 4, 4'-bipyridine molecule to form a centrosymmetric binuclear complex cation [Mn2L2(EtOH)2 (bipy]2+. The coordination geometry around Mn atoms is a distorted octahe-dron with equatorial plane N2O2 from the Schiff base ligand L. 展开更多
关键词 manganese() complex binuclear complex Schiff base crystal structure
下载PDF
含没食子酸-Cr(Ⅲ)络合物废水中Cr(Ⅲ)的去除
14
作者 霍昉 马宏瑞 +1 位作者 郝永永 李琴莲 《化工环保》 CAS CSCD 北大核心 2024年第3期377-383,共7页
以大分子络合物没食子酸(GA)-Cr(Ⅲ)与小分子络合物柠檬酸(CA)-Cr(Ⅲ)为对象,考察了二硫代氨基甲酸盐(DTC)类重金属捕集剂和季铵盐(QAS)类重金属捕集剂对Cr(Ⅲ)的去除效果,比较了混凝沉淀、超声等辅助处理技术对GA-Cr(Ⅲ)溶液中Cr(Ⅲ)... 以大分子络合物没食子酸(GA)-Cr(Ⅲ)与小分子络合物柠檬酸(CA)-Cr(Ⅲ)为对象,考察了二硫代氨基甲酸盐(DTC)类重金属捕集剂和季铵盐(QAS)类重金属捕集剂对Cr(Ⅲ)的去除效果,比较了混凝沉淀、超声等辅助处理技术对GA-Cr(Ⅲ)溶液中Cr(Ⅲ)去除效果的影响,筛选出适宜的除铬工艺为“混凝沉淀—重金属捕集”,并考察了该工艺对实际制革废水的处理效果。结果表明:在GA-Cr(Ⅲ)溶液中,Cr(Ⅲ)与GA络合形成了大分子聚合物,使Cr(Ⅲ)被包裹在分子内部,导致重金属捕集剂难以发挥作用,去除效果较差;经超声处理后,GA-Cr(Ⅲ)的络合结构遭到破坏,促使包裹在有机物间的Cr(Ⅲ)裸露出来,从而有利于重金属捕集剂捕集;混凝沉淀与DTC类重金属捕集剂联用时,对Cr(Ⅲ)的去除效果最好,GA-Cr(Ⅲ)溶液经该工艺处理后,Cr(Ⅲ)去除率可达79.6%;采用混凝沉淀与DTC/QAS类重金属捕集剂联用的方法对实际制革废水处理后,出水ρ(Cr)均低于1.5 mg/L,满足《污水综合排放标准》(GB8978—1996)中总铬的排放限值要求。 展开更多
关键词 没食子酸-cr() 重金属捕集剂 超声 絮凝
下载PDF
Synthesis and Crystal Structure of Novel Dimer of Bismuth(Ⅲ) Complex with Dithiotetrahydropyrrolocarbamate: [Bi(S_2CNC_4H_8)_2(NO_3)]_2
15
作者 YINHan-dong WANGChuan-hua MAChun-lin 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第5期565-567,共3页
A novel dimer of the bismuth(Ⅲ) complex with dithiotetrahydropyrrolocarbamate, [Bi(S_2CNC_4H_8)_2·(NO_3)]_2, was synthesized and the crystal structure was determined by X-ray single crystal diffraction. The crys... A novel dimer of the bismuth(Ⅲ) complex with dithiotetrahydropyrrolocarbamate, [Bi(S_2CNC_4H_8)_2·(NO_3)]_2, was synthesized and the crystal structure was determined by X-ray single crystal diffraction. The crystal belongs to a monoclinic system with space group P2_1/n, a=0.64718(13) nm, b=2.6738(6) nm, c=1.0423(2) nm, β=106.384(3)°, Z=4, V=1.730(3) nm^3, D_c=2.163 g/cm^3, μ=10.682 mm^(-1), F(000)=1072, R=0.0329, wR=0.0659. The structure shows a distorted pentagonal bipyramidal configuration with the seven-coordinated central Bi atom. In the crystal, the molecular packing in the unit cell reveals that the two adjacent molecules are symmetrically linked each other in the dimer by virtue of a couple of Bi-S interaction. 展开更多
关键词 Bismuth() complex Dithiotetrahydropyrrolocarbamate DIMMER crystal structure
下载PDF
Synthesis, Characterization and Crystal Structure of Quaternary Complex of Gadolinium (Ⅲ)
16
作者 朱龙观 蔡国强 +2 位作者 王国平 北川进 正冈重行 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第1期9-12,共4页
A new quaternary mixed anion complex of gadolinium(Ⅲ), [Gd(CH 3CH 2COO) 2(N O 3)(phen)] 2, was synthesized and structurally characterized. The ESR spectr um of the complex with effective g values of 5.314, 2 47... A new quaternary mixed anion complex of gadolinium(Ⅲ), [Gd(CH 3CH 2COO) 2(N O 3)(phen)] 2, was synthesized and structurally characterized. The ESR spectr um of the complex with effective g values of 5.314, 2 473 and 1.880 in poly crys talline powder at room temperature is quite different from the U spectrum. The c oordination number of Gd 3+ is nine with a monocapped square antiprism geom etry. And the stacking effect was observed in the complex. The crystal of the co mplex belongs to triclinic with space group P 1, a=0.9626(4) n m, b=0.9732(4) nm, c=1.1758(5) nm, α=102.45(1)°, β=108.16(1) °, γ=96.68(2)°, V=1.0018(7) nm3, Z=2, D c=1.80 g·cm -3 , μ(MoKα)=33.63 mm -1, F(000)=530, GOF=1.80, R=0.023 and R w=0.027. 展开更多
关键词 organic chemistry gadolinium() crystal s tructure mixed ligands ESR quaternary complex rare earths
下载PDF
Crystal Structure and Raman Spectrum of Neodymium(Ⅲ) Complex of p-Aminobenzoic Acid and 1,10-Phenanthroline
17
作者 郑晓梅 金林培 王明昭 《Journal of Rare Earths》 SCIE EI CAS CSCD 1994年第4期250-253,共4页
Crystal structure of tetra(1,10-Phenanthroline)neodymium (Ⅲ) tetra(4-aminobenzoate)-hydrate, [Nd(p-ABA)4·2Phen]H+3O·2Phen (p-ABA:p-aminobenzoate,Phen:1,10-phenanthroline) has been determined by X-ray diffra... Crystal structure of tetra(1,10-Phenanthroline)neodymium (Ⅲ) tetra(4-aminobenzoate)-hydrate, [Nd(p-ABA)4·2Phen]H+3O·2Phen (p-ABA:p-aminobenzoate,Phen:1,10-phenanthroline) has been determined by X-ray diffraction.The complex crystallizes in monoclinic, space group C2/c.The cell dimensions are a=1.9067 (5) nm,b=1.9192 (3) nm,c=2.0190 (4) nm,β=117.25 (2) °.V=6.568 (3) nm3, Mr= 1428.63,Z=4 and Dx= 1.45 g·cm-3.The coordination number of Nd atom is 10, and the coordinated polyhedron around the Nd atom is distorted trigonal prism. 展开更多
关键词 Neodymium() complex crystal structure Raman spectrum
下载PDF
Synthesis,Crystal Structure and Electrochemistry Properties of an Iron(Ⅲ) Complex Based on the 3,5-Pyridinedicarboxylate and Water Ligands
18
作者 冯勋 赵建社 +1 位作者 王利亚 师新阁 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第2期290-296,共7页
Reaction of 3,5-pyridine-dicarboxylic acid(3,5-PydcH2) with iron salt in hydrothermal condition results in the formation of a three-dimensional self-assembly network formulated as [C14H14Fe2N2O12]n,and it has been s... Reaction of 3,5-pyridine-dicarboxylic acid(3,5-PydcH2) with iron salt in hydrothermal condition results in the formation of a three-dimensional self-assembly network formulated as [C14H14Fe2N2O12]n,and it has been structurally characterized by elemental analysis,IR spectra and X-ray diffraction.It crystallizes in the monoclinic system,space group C2/c with a=9.9633(15),b=12.0942(18),c=7.4297(11)A and β=105.822o.The units of Fe2(pydc)2·2H2O are linked into a one-dimensional structure via the chelate carboxylate groups from the 3,5-pyridine-dicarboxylate.The interlayer hydrogen bonding interactions result in a three-dimensional supramolecular architecture.In the complex,the Fe(Ⅲ) ion displays a slightly distorted pentagonal bipyramidal geometry with seven coordination numbers.Cyclic-voltammetry measurement reveals the oxidation and reduction processes for the complex are quasi-reversible in nature. 展开更多
关键词 X-ray structure iron( complex TOPOLOGY CYCLIC-VOLTAMMETRY
下载PDF
Thermodynamic Stability Research of Metal Complexes with a Tripodal Amide Ligand and Crystal Structure of its Cobalt(Ⅲ) Complex
19
作者 高东昭 陈毅雯 +2 位作者 赵为为 张国英 孙亚秋 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第9期1136-1142,共7页
A new Co(Ⅲ) complex with a tripodal amide ligand [CoL(N3)3] (L = N-acetyl- N',N'-bis-[(2-pyridyl)methyl]-ethylenediamine) has been synthesized and characterized structurally by X-ray diffraction. It crystal... A new Co(Ⅲ) complex with a tripodal amide ligand [CoL(N3)3] (L = N-acetyl- N',N'-bis-[(2-pyridyl)methyl]-ethylenediamine) has been synthesized and characterized structurally by X-ray diffraction. It crystallizes in orthorhombic, space group Pnma with a = 9.2515(19), b = 12.729(3), c = 17.273(4) A, V = 2034.0(7) A3, C16H20CoN13O, Mr = 469.38, Dc = 1.533 g/cm3, μ(MoKα) = 0.884 mm^-1, F(000) = 968, Z = 4, the final R = 0.0392 and wR = 0.0818 for 2430 observed reflections. In the complex, the amide ligand L acts as a tridentate fashion and coordinates to the Co(Ⅲ) ion through three nitrogen atoms, while the other three positions of the Co(Ⅲ) center are occupied by three terminal azide anions. The complex is connected as a 1D chain structure by intermolecular hydrogen bonds between the uncoordinated amide groups. In order to investigate the coordination ability, thermodynamic stability of the ligand L with the first-series transition metal ions (Co(Ⅱ), Ni(Ⅱ), Cu(Ⅱ) and Zn(Ⅱ)) has been studied by potentiometric titration, and the results show that the order of their stability constants conforms to the Irving-Williams sequence. 展开更多
关键词 thermodynamic stability TRIPODAL amide ligand Co( complex
下载PDF
Synthesis,Crystal Structure and Interaction with DNA of a Novel Chromium(Ⅲ) Complex Containing Salicylaldehyde Semicarbazone
20
作者 岳蕾 周荫庄 +2 位作者 刘金丽 屠淑洁 肖岭梅 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第7期789-796,共8页
The novel chromium(Ⅲ) complex with salicylaldehyde semicarbazone was synthesized and characterized by IR spectra and single-crystal X-ray diffraction analysis. The crystal belongs to the orthorhombic system, space ... The novel chromium(Ⅲ) complex with salicylaldehyde semicarbazone was synthesized and characterized by IR spectra and single-crystal X-ray diffraction analysis. The crystal belongs to the orthorhombic system, space group Pbca with a = 8.9849(13), b = 12.0475(16), c = 34.522(5)A, V = 3736.9(9)A3, Z = 8, C16H18C1CrN6O5, Mr= 461.81, De= 1.642 g/cm^3, F(000) = 1896,A(MoKα) = 0.799 mm^-1, the final R = 0.0370 and wR = 0.0827 for 2908 observed reflections with I 〉 2σ(I). The interaction between the chromium(Ⅲ) complex with calf thymus DNA (Ct-DNA) has been investigated by absorption spectroscopy, fluorescence spectroscopy and viscosity measurements. The results indicated that the complex was bonded to Ct-DNA through a non-classical intercalative mode. 展开更多
关键词 chromium( complex SEMICARBAZONE crystal structure calf thymus DNA
下载PDF
上一页 1 2 86 下一页 到第
使用帮助 返回顶部