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1.
Me-NaHCO3-NH3-H2O体系和Me-NaOH-NaHCO3-H2O体系的热力学分析 总被引:1,自引:0,他引:1
通过对Me(Fe2+,Ni2+,Cu2+,Zn2+)-NaHCO3-NH3-H2O体系以及Me-NaOH-NaHCO3-H2O体系的热力学分析,得到各金属离子总浓度cMe与pH值的关系,确定了2种体系的完全共沉淀区域.热力学分析结果表明:在Me-NaHCO3-NH3-H2O体系中,Ni2+,Cu2+,Zn2+这3种离子和氨的配位能力很强.当总碳的浓度cC=1 mol·L-1且总氮的浓度cN=0.01 mol·L-1时,在pH=7.5~11范围内可实现完全共沉淀:当cN=0.05 mol·L-1且cC=3 mol·L-1时,在pH=70.5时可实现完全沉淀,但共沉淀范围较窄,不利于铁氧体组分的精确控制.在Me-NaOH-NaHCO3-H2O体系中,共沉淀区域由cC决定,当cC=1 mol·L-1,pH=7.5~11时可实现完全共沉淀. 相似文献
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通过对Fe3+/Ba2+/Co2+/Zn2+/Cu2+在NH4HCO3-NH3·H2O和NaOH-Na2CO3体系中的热力学分析,得到各金属离子总浓度(cMe)与pH值的关系,确定了2种体系中5种离子完全共沉淀的pH值范围.结果表明:在NH4HCO3-NH3·H2O体系中,Co2+、Zn2+、Cu2+3种离子和氨的配位能力很强,其中Cu2+与氨的配位能力最强,在相同的pH值条件下,Cu2+沉淀困难,5种金属离子的完全共沉淀区域由Cu2+决定.在NaOH-Na2CO3体系中,随总碳浓度(cc)的增加,Ba、Co、Zn、Cu的溶解度都随之减小,当cc=1.0 mol·L-1时,各金属离子完全共沉淀的pH值范围为7.5~11.在两种体系中,Fe的溶解度都是随pH值的增大而减小,最终达到平衡.以NaOH-Na2CO3 为沉淀剂.在pH=10.0的条件下,采用化学共沉淀法合成出了晶粒细小、粒度均匀的Y型纯相结构的平面六角铁氧体微粉. 相似文献
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通过对Fe^3+/Ba^2+/Co^2+/Zn^2+/Cu^2+在NH4HCO3-NH3·H2O和NaOH-Na2CO3体系中的热力学分析,得到各金属离子总浓度(cMe)与pH值的关系,确定了2种体系中5种离子完全共沉淀的pH值范围。结果表明:在NH4HCO3-NH3·H2O体系中,Co^2+、Zn^2+、Cu^2+ 3种离子和氨的配位能力很强,其中Cu^2+与氨的配位能力最强.在相同的pH值条件下,Cu^2+沉淀困难,5种金属离子的完全共沉淀区域由Cu^2+决定。在NaOH—Na2CO3体系中,随总碳浓度(cc)的增加,Ba,Co、Zn、Cu的溶解度都随之减小,当cc=1.0mol·L^-1时,各金属离子完全共沉淀的pH值范围为7.5~11。在两种体系中,Fe的溶解度都是随pH值的增大而减小,最终达到平衡。以NaOH-Na2CO3为沉淀剂,在pH=10.0的条件下,采用化学共沉淀法合成出了晶粒细小、粒度均匀的Y型纯相结构的平面六角铁氧体微粉。 相似文献
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采用草酸共沉淀法制备YBCO粉末,计算了不同pH值下草酸盐共沉淀粉末的沉淀率,并对制取YBCO前驱体粉末过程中的Ba(NO3)2-Y(NO3)3-Cu(NO3)2-H2C2O4-H2O体系进行热力学分析,采用XRD对制备的YBCO进行了分析计算。结果表明:溶液中不同草酸根离子浓度下各离子沉淀完全的最佳pH范围不同,当草酸浓度为0.1 mol·L-1,pH为2~6时,溶液中离子的沉淀率达到99%以上。随着草酸根离子浓度增大,完全沉淀时,共沉淀液中各金属离子所需的pH值范围增大。热力学计算与试验结果吻合。草酸共沉淀法制备的YBCO粉末物相纯度高,杂质少,颗粒细小,平均粒径为35.4 nm。 相似文献
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对甲基苯磺酰化蛋氨酸镧配合物的合成 总被引:1,自引:0,他引:1
合成了一种新型对甲基苯磺酰化蛋氨酸镧配合物, 并利用红外光谱、 紫外光谱及热重分析对配合物及配体的结构进行了表征和确认. 以对甲基苯磺酰化蛋氨酸镧配合物作为修饰剂, 研制了修饰碳糊电极, 该电极对镧离子具有能斯特响应, 为此建立了溶液中镧离子的直接电位分析法. 修饰电极对镧离子的能斯特响应工作曲线方程为E(mV)=-19.50pCLa(III)-363.50, 相关系数R=0.9996,线性范围为4.0×10-2~4.0×10- 6 mol · L-1, 检测下线为1.6 ×10- 6 mol · L-1, pH响应范围是3.2~6.0. 试验了14种外加离子对测定的影响, 结果表明Ca2+, Mg2+, Zn2+, Ba2+, Cu2+, Co2+等金属离子对测定有微弱干扰. 利用该修饰电极对人工合成样品中镧离子含量进行测定. 相似文献
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结果表明:在1.0 g氯化铵存在下,当0.1 mol·L-1硫氰酸铵溶液和1.0×10-3mol·L-1十二烷基三甲基溴化铵(DTAB)溶液的用量分别为0.5,1.0 mL时,且溶液的总体为10 mL,硫氰酸铵DTAB汞(Ⅱ)三元缔合物可浮于盐水相上形成界面清晰的两相,从而使汞(Ⅱ)被定量浮选,而Zn2+,Mn2+,Ni2+,Co2+,Cu2+,Cd2+等离子在此体系中不被浮选,实现了汞(Ⅱ)与这些常见离子之间的定量分离,对合成水样中微量汞(Ⅱ)进行定量浮选分离测定,浮选率为98.2%~102.0%. 相似文献
9.
光谱法研究金属离子与肿瘤抑制蛋白p53的DNA结合结构域的相互作用 总被引:1,自引:0,他引:1
利用荧光滴定法研究了9种金属离子与序列特异性的DNA结合结构域(p53DBD)的结合反应,其结合能力依次为Fe3+>Zn2+>Cu2+>Ca2+>Mg2+>Ba2+>Mn2+>Ni2+>Co2+.圆二色谱研究结果表明,Ba2+, Ca2+, Co2+, Mn2+及Ni2+并未引起蛋白二级结构变化; Zn2+, Mg2+及Fe3+诱导蛋白结构细微调整;而Cu2+结合导致蛋白螺旋结构大量丢失.ANS结合研究结果表明, Mg2+与Zn2+相似,诱导p53DBD蛋白表面疏水性增强,而Fe3+引起p53DBD蛋白表面疏水性降低.因此,Mg2+和Fe3+可能是影响或调节p53活性的潜在因子之一. 相似文献
10.
离子色谱法同时测定茶叶中七种金属元素 总被引:9,自引:0,他引:9
在含有阴、阳离子双功能基的离子色谱柱上.选用草酸和氯化钠的梯度洗脱体系同时将 Cu2+,Ni2+,Zn2+,Cd2+,Co2+,Mn2+和Pb2+七种金属离子完全分离。柱后采用新的衍生试剂2-[(5-溴-2-吡啶)-偶氮]-5-二乙氨基苯酚(5-Br-PADAP)进行衍生反应,检测波长为560nm,方法的检出限达到μg·L-1级。应用于茶叶样品的测定,结果满意。 相似文献
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Keli Zhong Jie Zhao Xue Zhou Shuhua Hou Yanjiang Bian Jianrong Li Lijun Tang 《中国化学》2016,34(12):1329-1334
A new (8‐hydroxyquinolin‐2‐yl)methylene picolinohydrazide derivative ( L ) has been successfully synthesized and characterized. The probe L displays high selectivity to Co2+ in CH3CN/HEPES (1:1, V/V, 10 mmol·L?1, pH=7.4) with a fluorescence "ON‐OFF" response. The Co2+ ion recognition event possesses some distinct features including rapid response, high selectivity and sensitivity, good anti‐interference ability and being applicable within a wide pH range. Based on job's plot and ESI‐MS studies, the 1:1 binding mode was proposed. The binding constant of L and Co2+ is 1.63×108 L·mol?1 and the detection limit is 1.15 µmol·L?1. Natural water samples experiments revealed that probe L can be potentially applied to the detection of Co2+ in real environment. 相似文献
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Dmitry Yu. Naumov Anton I. Smolentsev 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(5):i49-i50
The structure of barium chlorite hydrate, Ba(ClO2)2·3.5H2O, has been determined by single‐crystal X‐ray analysis at 150 K. The structure is monoclinic, space group C2/c, with Z = 8. It contains layers of Ba2+ cations coordinated by ClO2− anions and water molecules. There are also solvate water molecules involved only in hydrogen bonding of the layers. Three solvate water O atoms are on sites of twofold symmetry, while all other atoms are in general positions. The full coordination environment of the Ba2+ cation consists of ten O atoms belonging to six chlorites and three water molecules, forming a bicapped square antiprism. 相似文献
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Yu‐Ling Wang 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(11):m522-m524
In the title compound, {[Zn(C10H8N2)(H2O)4](C6H5O4S)2·3H2O}n, the Zn atom, the bipyridine ligand and one of water molecules are located on twofold rotation axes. The Zn atom is coordinated by four O atoms from four water molecules and two N atoms from two 4,4′‐bipyridine molecules in a distorted octahedral geometry. The Zn2+ ions are linked by the 4,4′‐bipyridine molecules to form a one‐dimensional straight chain propagating along the c axis. The 4‐hydroxybenzenesulfonate counter‐ions are bridged by the solvent water molecules through hydrogen bonds to generate a two‐dimensional layer featuring large pores. In the crystal packing, the intralayer pores form one‐dimensional channels along the c axis, in which the one‐dimensional [Zn(C10H8N2)(H2O)4]2+ chains are encapsulated. Electrostatic interactions between cations and anions and extensive hydrogen bonds result in a three‐dimensional supramolecular structure. 相似文献
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Shuji Oishi Setsuo Kashino Hiroyuki Ishida Takeo Fukunaga 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(1):18-19
Single crystals of a new polymorph of the title compound, barium(II) 3,6-dichloro-2,5-dihydroxy-1,4-benzoquinone trihydrate, Ba2+·C6Cl2O42−·3H2O, have been grown in sodium metasilicate gel. Each Ba2+ cation is coordinated by eight O atoms. The Ba2+ cations are bridged by an O atom of a ligand around the centre of symmetry at Wyckoff position 4a and by the O atom of a water molecule around the centre of symmetry at Wyckoff position 4b, forming a sheet parallel to the (100) plane. Loose contacts are found around one of the water molecules, as observed in the Cmca form. 相似文献
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The interaction between mercuric ion and apoCopC in the absence or presence of cupric ion was investigated through difference UV spectra in Hepes buffer (10 mmol·L^-1) at pH 7.4. The results suggest that mercuric ion can bind to C- and N-terminal binding sites of apoCopC, and the conditional binding constants were calculated to be kN=(6.79± 1.12)× 10^6 mol^-1·L and kc=(3.06±0.05)× 10^5 mol^-1·L. Using urea as a chemical agent, the conformational stabilities of apoCopC and HgN^2+ -CopC-Hgc^2+ were monitored by fluorescence spectrum in Hepes buffer (50 mmol·L^-1) at pH 7.4. The free energy of stabilization is (14.69±0.85) and (16.66±0.55) kJ.mol^-1, respectively. HgN^2+ -CopC-Hgc^2+ is more stable than apoCopC. 相似文献
16.
Burkhard Schulz Julia Bricks Yan‐Qin Li Ute Resch‐Genger Günter Reck 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):o402-o404
1‐Methyl‐2‐[4‐phenyl‐6‐(pyridinium‐2‐yl)pyridin‐2‐yl]pyridinium diperchlorate, C22H19N32+·2ClO4−, (I), and 2‐[4‐(methoxyphenyl)‐2,2′‐bipyridin‐6‐yl]‐1‐methylpyridinium iodide, C23H20N3O+·I−, (II), both crystallize in the monoclinic space group P21/c. In contrast with the monocharged molecule of (II), the doubly charged molecule of (I) contains an additional protonated pyridine ring. One of the two perchlorate counter‐anions of (I) interacts with the cation of (I) via an N—H⋯O hydrogen bond. In (II), two molecules related by a centre of symmetry are connected by weak π–π interactions, forming dimers in the crystal structure. 相似文献
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Viktor A. Tafeenko Vladimir V. Chernyshev 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(6):m298-m300
The coordination of the 3‐cyano‐4‐dicyanomethylene‐5‐oxo‐4,5‐dihydro‐1H‐pyrrol‐2‐olate anion to ZnII, the apical sites of which are occupied by two water molecules, results in the formation of two‐dimensional layers of the title coordination polymer, {[Zn(C8HN4O2)2(H2O)2]·2H2O}n, in which the ZnII cations lie on inversion centres in space group C2/c, with water ligands in the apical sites of octahedral geometry. Hydrogen bonds between coordinated and lattice water molecules, and π–π stacking interactions between the anions link adjacent layers into a continuous framework. 相似文献
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Hong‐Chang Liang Marcel M. Hetu Kraig A. Wheeler Lev N. Zakharov Arnold L. Rheingold 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(11):m519-m521
In the title compound, [Zn(C2H3N)(C16H21N3O)](ClO4)2·H2O, the ZnII ion is coordinated by two pyridyl N atoms, one amine N atom, and an ethanol O atom from the N,N′,N′′,O‐tetradentate 2‐[bis(2‐pyridylethyl)amino]ethanol donor ligand. The fifth coordination site is filled by an acetonitrile N atom, and there is one solvent water molecule in the asymmetric unit. The 2+ charge of the cationic portion of the complex is balanced by two perchlorate counter‐anions. 相似文献
19.
Yu‐Xiang Gao Xi‐Quan Che Jing‐Wei Wang 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(9):m440-m442
In the novel title binuclear zinc(II) Schiff base complex, bis(μ‐11‐thiosemicarbazonoindeno[1,2‐b]quinoxaline‐8‐carboxylato)bis[(dimethyl sulfoxide)zinc(II)] dimethyl sulfoxide trisolvate, [Zn2(C17H9N5O2S)2(C2H6OS)2]·3C2H6OS, each ZnII atom is five‐coordinated and situated in a distorted square‐pyramidal environment, coordinated by two L2− ligands and one dimethyl sulfoxide molecule. Each L2− ligand, which coordinates to two ZnII atoms, has two parts. One part, acting in a tridentate chelating mode, coordinates to one ZnII atom through two N atoms and one S atom, while another part coordinates to another ZnII atom through a monodentate carboxylate group. The whole complex has a dimeric structure. The coordination mode of the nearly planar L2− ligand is quite different from the most common mode for Schiff bases. 相似文献