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1.
Kinetic features of radical polymerization of styrene initiated by tert-butyl perbenzoate in the presence of tris(N,N-dimethyldithiocarbamato)cobalt(III) (CoL3) and its adduct with iodine (CoL3 · 2I2) were studied. The optimal concentration ratios of the activators and tert-butyl perbenzoate, providing fast styrene polymerization at 338–368 K, were determined.  相似文献   
2.
A new hydrolyzable tannin substance has been isolated from an anqueous hydrolysate of an aqueous-acetone extract of the fruit ofRosa platyacantha — 1-dehydrotrigalloyl--D-glucose — and it has been named platyacanthin. The substance is a minor component of the tannin complex.S. M. Kirov Kazakh State University, Alma-Ata. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 829–831, November–December, 1985.  相似文献   
3.
The crystal structure of the product of the condensation of (salicylideneamino)nitroguanidine with salicylaldehyde on a Ni2+ ion template, K[Ni(C15H10N5O4)] · DMF, has been studied. It was established that a planar Ni complex, consisting of isolated [NiL] anions and solvated [K+ · DMF] cations, is formed. The negative charge of the anion is localized mainly on the O atoms of the nitro group. The nitroguanidine fragment of the ligand occurs in the tautomeric form, which was not reported previously.Deceased in 1995Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 2273–2277, September, 1996.  相似文献   
4.
Tartratogermanates of alkaline metals and ammonium are synthesized for the first time using different solvents (water, acetonitrile) and starting reagents (GeO2 and GeCl4): dimeric Kat2[Ge2(OH)2(μ-Tart)2] · 4.5H2O (H4Tart is D-tartaric acid, Kat = Na (I) and K (II)) and polymer (NH4)2n [Ge2(μ-O)(μ-Tart)2] n · nCH3CN · nH2O (III). The complexes are characterized by elemental analysis, IR spectroscopy, and X-ray diffraction analysis. The structure of complex II contains binuclear isolated [Ge2(OH)2(μ-Tart)2]2-complexes. In complex III, the oxo ligands join the binuclear fragments into polymer chains.  相似文献   
5.
Russian Journal of General Chemistry - [Co(HydrHIz)] and [Ni(HydrHIz)]?2H2O (М = Co, Ni) complexes have been obtained via the reaction of M(CH3COO)2 with...  相似文献   
6.
Complexes of MX2(M = Co, Zn; X = Cl, Br) with 1-piperidinyl dimethylcarbamodithioate (L) of composition [MLX2] have been synthesized. The compounds have been studied by elemental analysis; X-ray diffraction; thermogravimetry; conductometry; magnetochemistry; and IR, 1H NMR, and electronic absorption spectroscopy. The ligand molecule is coordinated to the metal atoms in a bidentate chelating mode through the thione sulfur atom and the sulfenamide nitrogen atom to form a five-membered chelate ring. The structures of L and [ZnLBr2] have been determined by X-ray crystallography.  相似文献   
7.
The catalytic activity of citric (H4Citr) and malic (H3Mal) acids, their coordination compounds with germanium(IV) H2[Ge(HCit)2] and H2[Ge(Mal)2], and germanium dioxide GeO2 in polycondensation of maleic anhydride and ethylene glycol at various temperatures was studied (catalyst: ethylene glycol molar ratio 0.01: 1). The process kinetics was evaluated and the time of its completion was determined. The copolymerization kinetics of some of the prepared oligoesters with triethylene glycol dimethacrylate was studied, and the copolymer properties were determined.  相似文献   
8.
Four heterometallic tartratogermanate complexes, namely [Cu2Ge2(Tart)3(H2O)10] n · 3nH2O and (H3O)[LnGe2(Tart)3(H2O)6] · nH2O (Ln3+ = Gd, n = 3.5; Tm, n = 3; Yb, n = 3), have been prepared via the reaction between germanium tetrachloride and D-tartaric acid (H4Tart) in aqueous acetic acid. All complexes contain {Ge2(Tart)3} n 4n- polymer chains. The Cu2+ and Ln3+ atoms coordinate only Tart carbonyl oxygen atoms.  相似文献   
9.
In continuation of a systematic study of bis(citrate)germanates, we synthesized a number of heterometallic germanium(IV) and 3d metal complexes based in citric acid (H4Cit) with the molecular formula [M(H2O)6][Ge(HCit)2] · nH2O, where M = Fe, n = 4 (I); Co, n = 2 (II); Ni, n = 2 (III); Cu, n = 1 (IV); Zn, n = 3 (V). The complexes were characterized by elemental analysis, X-ray diffraction, thermogravimetry, and IR spectroscopy. The X-ray diffraction analysis of compound I was performed. Crystals are monoclinic, a = 10.091(4) Å, b = 11.126(4) Å, c = 10.996(4) Å, β = 100.966(6)°, V = 1212.1(8) Å3, Z = 4, space group P21/n, R1 = 0.0561 for 2266 reflections with I > 2σ(I). Compound I is composed of centrosymmetric octahedral complexes-[Ge(HCit)2]2? anions and [Fe(H2O)6]2+ cations—and crystallization water molecules. Structural units in compound I are combined by a hydrogen bond system.  相似文献   
10.
The systems ZnCl2–2-(7-bromo-2-oxo-5-phenyl-2,3-dihydro-1H-1,4-benzodiazepin-1-yl)acetohydrazide (Hydr)–propan-2-ol, ZnCl2–Hydr–pyruvic acid (HPv), and Zn(CH3COO)2–Hydr–isatin(HIz)–propan-2-ol were studied. Optimal synthesis conditions were determined, and the complexes [Zn(Hydr)2Cl2], [Zn(HydrHPv)2Cl2], and [Zn(HydrIz)2] were isolated. The complexes were characterized by elemental analysis, thermogravimetry, IR spectroscopy, and mass spectrometry. The electrical conductivities of the complexes were measured. The local environment of the central atom in the coordination entity was determined by X-ray absorption spectroscopy.  相似文献   
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