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1.
测定了一系列金属离子对没食子酸(GA)-KBrO3-H2SO4体系非催化振荡反应的影响。从实验中发现,金属离子对上述振荡反应的影响可分为三类:(1)Ce3+、Mn2+、Fe(phen)2+3、Bi3+和Cr3+,可促进GA-BZ体系的非催化振荡反应,同时可产生连续振荡等复杂振荡现象;(2)Cu2+、Zn2+、L3+a、Sm3+、Eu3+、Ni2+、Co2+、Hg2+、Ag+和Hg2+2对振荡反应具有强烈的抑制作用;(3)碱金属和碱土金属离子对振荡反应几乎不发生影响。对上述金属离子的影响机理进行了探索,说明金属离子的电极电势、金属离子与GA形成络合物或与Br-形成沉淀是影响上述振荡反应的主要原因,而金属离子与有机物中间体的偶合催化导致产生连续振荡反应  相似文献   

2.
高分子负载希夫碱对金属离子的吸附特性   总被引:2,自引:0,他引:2  
本文报导两种聚氯乙烯负载希夫碱,考察了它们对Cu^2+,Hg^2+,Ag^+,Co^2+,Ni^2+等金属离子的吸附作用。  相似文献   

3.
在γ-Al2O3中加入Zn2+,Mg2+,Cu2+或Cr3+后用漫反射光谱法研究了它们对随后加人的Co分布的影响,同时还研究了这些离子对水煤气变换反应催化剂CoMoK/Al2O3的催化活性的影响.发现Zn2+,Mg2+具有阻止Co进入载体内层的作用,Cu2+,Cr3+的作用则相反.四面体配位倾向强的金属离子能阻止Co进入载体内层,从而促进水煤气变换反应的催化活性,而八面体配位倾向强的金属离子的效果刚好相反.在650℃下,100gAl2O3含7gMgO时,Mg能最大限度地阻止Co向Al2O3内层扩散,从而提高了CoMok/Al2O3的催化活性.  相似文献   

4.
笼形聚氨肟树脂的研究:碱处理对吸附性能的影响   总被引:3,自引:1,他引:3  
研究碱处理的笼形聚氨肟树脂(BCAO)对二价金属离子的吸附行为。吸附结果若生成2:1配的,得Mg^2+,Ca^2+,Ba^2+,Mn^2+,Co^2+,Ni^2+,Zn^2+,Cd^2+,Pb^2+,Cu^2+离子的吸附效率分别是27.1、29.2、30.4、29.0、27.1、30.8、45.0、39.8、60.3、62.1%,Hg^2+离子的吸附效率高达105%,表明在吸附过程中同时生成2:1  相似文献   

5.
笼形聚偕氨肟树脂的研究:酸处理树脂的吸附性能   总被引:5,自引:3,他引:5  
笼形聚偕氨肟树脂(CAO)经盐酸处理垢,伯胺基转变成胺盐。酸处理笼形聚偕氨肟树脂(ACAO)对Mg^2+,Ca^2+,Ba^2+,Mn^2+,Co^2+,Ni^2+离子不吸附;对Zn^2+,Cd^2+,Cu^2+,Pb^2+离子的吸附效率在20%以下,但对Hg^2+离子的吸附效率则高达71.2%;对一些金属络阴离子的吸附效率顺序是Fe(CN)^2-6>Cr2O^2-7>MoO^2-4>PtCl^2  相似文献   

6.
以金属Ni(Ⅱ)离子为模板,合成了高分子多乙烯多胺络合吸附剂。研究了它们对重金属离子(Cu^2+,Ni^2+,Zn^2+,Co^2+)的吸附特性。结果表明,这类吸附剂对Cu(Ⅱ)、Ni(Ⅱ),Zn(Ⅱ)、Co(Ⅱ)离子的吸附容量分别达239.60、231.30、131.83、81.23mg/g(干);相应选择性顺序为Cu(Ⅱ)≈Ni(Ⅱ)>Zn(Ⅱ)>Co(Ⅱ)。  相似文献   

7.
研究了在抗坏血酸存在下的6mol/L HBr介质作流动相,以PTFE(聚四氟乙烯)负载的乙醚作固定相,反相萃取层析使微量Ga(Ⅲ),In(Ⅲ)与Fe^3+、Tl^3+、Mo^6+、Au^3+、Ti^4+、Bi^3+、Al^3+、Mg^2+、Ca^2+、Ni^2+、Co^2+、Cd^2+、Zn^2+、Pb^2+、Cu^2+等多种离子分离。留于柱上的铟、镓分别用HCl(4mol/L)-H2O2(3%)  相似文献   

8.
本文用KBr压片法测定了氨基膦酸树脂NP-500,SL—467,SL—411的H型、Na型以及分别吸附了Cu2+,Ni2+,Co2+离子后的红外光谱图.谱图分析发现,在相同的吸附条件下,同一种树脂分别吸附了Cu2+,Ni2+,Co2+后,其吸附量愈大,谱图中C-N-C谱峰的位移值越大,则树脂对该金属离子的选择性愈高。结果表明,NP-500,SL—467,SL-411树脂对过渡元素Cu2+,Ni2+,Co2+的选择性顺序为Cu2+>Ni2+>Co2+。另外,本文还观察到谱图中C-N-C谱峰的位移值随金属离子的负载量的增加而增大,有可能通过红外光谱法来研究氨基膦酸树脂对金属离子的负载量。  相似文献   

9.
研究了在抗坏血酸存在下的6mol/LHBr介质作流动相,以PTFE(聚四氟乙烯)负载的乙醚作固定相,反相萃取层析使微量Ga(Ⅲ)、In(Ⅲ)与Fe3+、Tl3+、Mo6+、Au3+、Ti4+、Bi3+、Al3+、Mg2+、Ca2+、Ni2+、Co2+、Cd2+、Zn2+、Pb2+、Cu2+等多种离子分离。留于柱上的铟、镓分别用HCl(4mol/L)-H2O2(3%)及HBr(1mol/L)洗脱进行连续分离与测定。本方法已应用于地质样品中微量镓、铟的连续分离与测定  相似文献   

10.
李全民  张丽敏 《分析化学》1999,27(10):1208-1210
研究了丙醇-溴化十六烷基三甲胺9CTMAB)-(NH4)2SO4-水体系萃取分离泵的行为及与常见离子分离条件。试验表明:调节pH1.0或3.0,能使Hg从Fe^3+,Co^2+,Ni^2+m,Zn^2+,Mn^2+,Cu^2+,Al63+等离子混合液中分离出来。  相似文献   

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12.
The first alkali metal transition metal acetylides of general composition A2M0C2 (A = Na ? Cs, M0 = Pd, Pt) were obtained by solid state reactions of alkali metal acetylides with palladium and platinum. They are characterized by chains, which are separated by alkali metal ions. Analogous chains also separated by alkali metal ions are the characteristic structural feature of acetylides of composition AMIC2, which are accessible by reacting AC2H with MII in liquid ammonia (A = Li ? Cs, MI = Cu, Ag, Au). Despite their structural similarities they possess different properties, as acetylides of composition A2M0C2 are semiconductors with very small indirect band gaps and slightly extended C–C distances compared to a C–C triple bond, whereas acetylides of composition AMIC2 show a typical salt‐like behavior with C–C distances close to the expected value for a C–C triple bond of 120 pm. But with the help of simple chemical models these differences can be made plausible. Furthermore, it is shown that only by a combination of different methods (powder diffraction with X‐rays and neutrons, solid state NMR spectroscopy, Raman spectroscopy) it was possible to characterize this new class of compounds structurally and chemically.  相似文献   

13.
A novel one-pot reaction producing a metal vinylidene structure in a five-membered ring by cyclization of a multiyne has been achieved. The ring strain and the high stability of the cyclic metal vinylidene complexes have been analyzed experimentally and computationally. The metal vinylidene unit in a fused-ring complex is unreactive to both nucleophiles and electrophiles. It reacts however at the nearby carbonyl group achieving the unprecedented conversion of metal tributing factors for the aromaticity-driven process has been studied by DFT calculations.  相似文献   

14.
Zirconia powders are prepared by reaction of a zirconium precursor with an alkali metal nitrate. The major part of the reactions takes place before the melting points and then the reactions go slowly to completion at 450°C in the molten salts. The roles of the precursor and the alkali metal ion are discussed considering the reaction between two precursors, octahydrated zirconium oxychloride and zirconium tetrachloride, and two nitrates, LiNO3 and NaNO3, and some resulting physico-chemical differences. The obtained zirconia powders contain very small amounts of alkali metal ions which act as stabilizing agent. Their effect on the balance tetragonal-monoclinic ZrO2 depends upon the homogeneity of their distribution which is related to their ability to diffuse inside the bulk of particles and their polarizing power when located mainly on the surface.  相似文献   

15.
IntroductionPlatinumand gold surfaces can adsorb a wide vari-ety of ions, atoms and molecular functional groups,which is often accompanied by oxidation-reduction ordissociation of them. Numerous previous works havemade great progress in studying the surfa…  相似文献   

16.
A pair of diastereomeric dinuclear complexes, [Tp′(CO)BrW{μ-η2-C,C′2-S,P-C2(PPh2)S}Ru(η5-C5H5)(PPh3)], in which W and Ru are bridged by a phosphinyl(thiolato)alkyne in a side-on carbon P,S-chelate coordination mode, were synthesized, separated and fully characterized. Even though the isomers are similar in their spectroscopic properties and redox potentials, the like-isomer is oxidized at W while the unlike-isomer is oxidized at Ru, which is proven by IR, NIR and EPR-spectroscopy supported by spectro-electrochemistry and computational methods. The second oxidation of the complexes was shown to take place at the metal left unaffected in the first redox step. Finally, the tipping point could be realized in the unlike isomer of the electronically tuned thiophenolate congener [Tp′(CO)(PhS)W{μ-η2-C,C′2-S,P-C2(PPh2)S}Ru(η5-C5H5)-(PPh3)], in which valence trapped WIII/RuII and WII/RuIII cationic species are at equilibrium.  相似文献   

17.
金属及其配合物与生物分子相互作用机理的研究进展   总被引:3,自引:0,他引:3  
金属及其配合物与DNA、蛋白质、氨基酸等生物分子的作用机理研究,是诊断和治疗由金属引起的疾病的重要环节。本文对近十年来金属及其配合物与生物分子相互作用机理的研究进展进行了综述,并提出了该研究领域的新动向。  相似文献   

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20.
Nanocrystalline metals have received widespread interest and found various applications owing to their magnetic and catalytic properties and in energy‐related fields. A flexible approach for the growth of nanoalloys with controlled properties and well‐defined structures on the atomic scale is thus greatly desired. A new synthetic method that avoids incompatible reduction potentials and rates would be critical to grow metal nanostructures with high purities and the desired stoichiometries. A metal‐redox strategy that employs spontaneous oxidation/reduction reactions to grow nanocrystalline alloys using molecular‐scale zerovalent metal precursors is now described. The selection of suitable zerovalent metal species allows for thermodynamic control of the compositional stoichiometry during the temperature‐dependent formation of the metal alloy nanoparticles. A practical and scalable strategy for nanoalloy growth that can potentially produce key metal components of superior metallurgical quality for catalytic and magnetic systems has thus been developed.  相似文献   

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