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41.
以MCl2和配体L(L=1,10-菲罗啉-5,6-二酮)为原料,合成了标题配合物MLCl2,M=NiⅡ,CuⅡ,ZnⅡ,并经元素分析、热谱、IR和摩尔电导表征.三者均为四配位的电中性配合物,热稳定性高于500K,易溶于DMF、DMSO和吡啶,可溶于乙腈和水.它们在DMF中于350nm和315nm附近显示出强的M-L荷移跃迁 相似文献
42.
The solvent extraction of cobalt(II), nickel(II) and copper(II) using 2,4-pent-dione (Hacac) and 4-phenyl-2, 4-but-dione (Hbzac)
is carried out by varying the reagent concentration and pH of the aqueous phase. Each of these metals is quantitatively separated
(≈ 98%) from their binary mixtures with monovalent (Ag), divalent (Mn, Zn, Cd, Hg, Mg, Sn, Pb) and trivalent (Cr, Fe) metals.
The extraction constants are calculated from the metal distribution data using linear regression analysis. The extracted species
is MA2 in each case. A most significant result is separation of copper(II) from iron(III) which otherwise interferes when extracted
from the acidic medium. 相似文献
43.
Dynamics of changes in microstresses during thermal decomposition of Cu(HCOO)2 crystals and their effect on the thermal decomposition kinetics were studied by IR spectroscopy at 105 to 120 °C. The formation of solid intermediate HCOOCu was observed, and the dynamics of its accumulation was followed. Kinetic regularities of transformation of HCOO groups were compared with those for gas evolution.For Communication 1, see Ref. 1.Translated from Izvestiya va Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 350–354, February, 1996. 相似文献
44.
Gurkan Hizal Umit Tunca Sermin Aras Humeyra Mert 《Journal of polymer science. Part A, Polymer chemistry》2006,44(1):77-87
Copper‐catalyzed controlled/living radical polymerization (LRP) of styrene (St) was conducted using the silica gel‐supported CuCl2/N,N,N′,N′,N″‐pentamethyldiethylenetriamine (SG‐CuCl2/PMDETA) complex as catalyst at 110 °C in the presence of a definite amount of air. This novel approach is based on in situ generation and regeneration of Cu(I) via electron transfer reaction between phenols and Cu(II). Sodium phenoxide or p‐methoxyphenol was used as a reducing agent of Cu(II) complexes in LRP. The number–average molecular weight, Mn,GPC, increases linearly with monomer conversion and agrees well with the theoretical values up to 85% conversion The molecular weight distribution, Mw/Mn, decreases as the conversion increases and reaches values below 1.2. The catalyst was recovered in aerobic condition and reused in copper‐catalyzed LRP of St. For the second run, the number–average molecular weights increased with monomer conversion and the polydispersities decreased as the polymerization proceeded and reached to the value <1.3 at 81% conversion. The recycled catalyst retained 90% of its original activity in the subsequent polymerization. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 77–87, 2006 相似文献
45.
The reaction system (NH4)3VS4/CuCl/PPh3/Et4NBr afforded a series of [VS4-Cun] dusters with various core configurations in the solid state at low heating temperature. The structural regularity of [VS4-Cun] dusters and the influence of the CuCl:(NH4)3VS4 ratio as well as that of reaction temperature and time on the formation of duster core have been summarized. The reaction mechanism of forming V-Cu-S clusters has also been explored. 相似文献
46.
本文研究了硫酸根阴离子对1-苯基-3-甲基-4-苯甲酰基吡唑酮-5(HPMBP,HL)及三辛胺(TOA)协同萃取镨(Ⅲ)及钕(Ⅲ)的影响。发现在SO_4~(2-)体系中协萃机理为:(LnL_3)_o+(HTOAL)_o(HTOA~+LuL_4~-)_o及(HLnL_4)_o+(TOA)_o(HTOA~+LnL_4~-)_o式中Ln~(3+)=Pr~(3+),下标“o”指示有机相中物种,无下标指示水相中物种。固体萃合物的红外光谱及元素分析数据确证了上述机理。 相似文献
47.
The study of the partitioning mechanism of methyl orange in an aqueous two-phase system 总被引:2,自引:0,他引:2
An aqueous two-phase system of dodecyl triethylammonium bromide (C12NE, cationic surfactant) and sodium dodecyl sulfate (SDS, anionic surfactant) mixture is proposed for the extraction of some dyes and porphyrin compounds. Transparent two phase-systems are formed when the surfactant concentrations and C12NE/SDS ratios are in certain regions. In this study, the aqueous two phase-systems were prepared by mixing 0.1 mol l−1 C12NE and SDS with a molar ratio of 1.7:1.0. The results showed that negatively charged chlorophyll (sodium copper chlorophyllin) and positively charged dye (methyl violet) were efficiently extracted into the upper phase. The negatively charged methyl orange (pH>7) was moved into the upper phase mostly while amphoteric methyl orange (pH<3) was distributed in the two phases uniformly. Except for hydrophobic force, charge interaction between solute and surfactant also play an important role in the extraction process. 相似文献
48.
49.
铜配合物具有多变的配位结构,可活化小分子,可用于氧转移、氧化加成、新陈代谢、均相催化等许多领域。还可以用作金属酶的化学模拟和配合物结构及反应性能研究方面[1-3]。本文以2,3 二羧酸 吡啶为辅助配体及[(PPh3)2Cu(BH4)]作为起始原料,室温下,通过取代反应合成了单核铜(Ⅰ)配合物[(PPh3)2Cu(C7H4NO4)],经元素分析、电导、光电子能谱、红外光谱及单晶XRD方法对配合物进行了表征。1 实验部分1 1 仪器和试剂意大利ERBA 1106元素分析仪,JA96 970等离子光谱仪,Nicolet170SX分析仪(CsI压片),AV 300Bruker分析仪(CDCl3溶剂,8… 相似文献
50.
催化动力学光度法测定痕量铜的研究 总被引:5,自引:1,他引:5
本研究了在氨水介质中铜(Ⅱ)催化过氧化氢氧化亮黄的褪色反应及其动力学条件,建立了一种超高灵敏、高选择性的测定环境试样中痕量铜的新方法,可测定0.004~0.5μg/25mL范围内的铜(Ⅱ)。 相似文献