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791.
Srinivasan Natarajan Wilhelm Klein Martin Panthfer Leo van Wüllen Martin Jansen 《无机化学与普通化学杂志》2003,629(6):959-962
A room temperature reaction of zinc acetate, tributyl borate and N, N, N′N′‐tetramethylethylenediamine (tmen) in a mixture of water and 1‐butanol has given rise to a new bis‐(hexaborato)‐zincate, [(Me)2NH(CH2)2NH(Me)2][{Zn(B6O7(OH)6}2]·2H2O ( I ). The structure, determined by single crystal X‐ray diffraction, (P1, a = 8.3014(2), b = 9.2489(2), c = 10.442(2)Å, α = 107.71(3), β = 94.22(3), γ = 100.02(3)°, V = 749.6(3)Å3 = Z = 1, R1 = 0.0387, wR2 = 0.105), consists of anionic molecular Zn hexaborate units forming a herringbone arrangement, through strong hydrogen bond interactions, with the amine molecule situated between the chains. Compound I is the first bis‐(hexaborato)‐zincate, to our knowledge, that has been synthesized in the presence of an organic amine. 相似文献
792.
I. C. Pius Aruna Kadam M. Subba Rao V. K. Rao P. R. Natarajan 《Journal of Radioanalytical and Nuclear Chemistry》1990,146(3):151-158
Results of experiments on the adsorption of plutonium (IV) on alumina and their application to the recovery of plutonium from analytical waste solutions containing phosphoric-nitric acid are reported. Distribution ratios of plutonium (IV) between alumina and solutions containing varying concentrations of phosphoric acid and nitric acid are determined. The influence of various ions like UO2
2+, Fe3+, MoO4
2–, VO2+ and SO4
2– on the distribution ratio is evaluated. Saturation values of adsorption of plutonium (IV) on alumina and optimum conditions for loading and elution of plutonium on a column packed with alumina are described. 相似文献
793.
The β-ZnMoO4/MWCNT nanocrystal composites were synthesized using hydrothermal method. The physicochemical properties such as structure, morphology and bandgap of synthesized photocatalysts were characterized using PXRD, UV-vis DRS, FTIR, FT-Raman, SEM and TEM analytical methods. PXRD pattern shows the peak shift in the case of synthesized ZnMoO4/MWCNT which confirms the formation of nanocomposites. Moreover, the strong absorbance in UV region which was evidenced in UV-vis DRS spectra for all the case of synthesized ZnMoO4 and ZnMoO4/MWCNT composites. From the SEM and TEM images, the MWCNT was found to have adhered over the ZnMoO4 nanocrystals. Compared to bare β-ZnMoO4, β-ZnMoO4/MWCNT nanocrystal composites exhibited significant higher photocatalytic activity under ultraviolet light emitting diodes (UVLEDs) irradiation for the degradation of nitrobenzene (NB; 2.606 × 10?4 M). This may be due to the effective charge transfer in the composite and optimized electron hole pair recombination. The photocatalytic activity of the synthesized photocatalysts was also studied under visible LEDs and it is observed that the photocatalytic degradation of NB was 97%, 77%, 65% and 52% under the irradiation of UV, blue, green, and red LEDs respectively. 相似文献
794.
Karvembu Ramasamy Jayabalakrishnan Chinnasamy Natarajan Karuppannan 《Transition Metal Chemistry》2002,27(6):574-579
Hexacoordinated binuclear ruthenium(III) complexes of the type {[RuX2(EPh3)2]2(bis--dk)} [X = Cl or Br; bis--dk = thiobis(-diketone)] have been prepared by reacting [RuCl3(PPh3)3], [RuCl3(AsPh3)3], [RuBr3(AsPh3)3] or [RuBr3(PPh3)2(MeOH)] with thiobis(-diketones) in a 2:1 molar ratio in benzene, and characterized by analytical, spectroscopic (i.r., electronic e.p.r.) and cyclic voltammetric data. An octahedral structure has been proposed. The complexes are effective catalysts for the oxidation of PhCH2OH and cyclohexanol to PhCHO and cyclohexanone respectively using N-methylmorpholine-N-oxide as co-oxidant. Some of the complexes have been subjected to antifungal activity studies. 相似文献
795.
Several new hexa-coordinated ruthenium(II) complexes of the type [Ru(CO)(LL)(B)] (where, LL = anthacac, anthdibm, 2-amtpacac or 2-amtpdibm; B = PPh3 or py or pip or morph) have been prepared by reacting [RuHCl(CO)(PPh3)3] or [RuHCl(CO)(PPh3)2(B)] with tetradentate Schiff bases such as bis(anthranilic acid)acetylacetimine (H2-anthacac), bis(anthranilic acid) dibenzoylmethimine (H2-anthdibm), bis(2-aminothiophenol) acetylacetimine (H2-2-amptacac) or bis(2-aminothiophenol) dibenzoylmethimine (H2-2-amtpdibm). The complexes have been characterised by elemental analyses and spectral (i.r., electronic spectra, 1H- and 31P-n.m.r.) data. An octahedral structure has been tentatively proposed for the complexes, which were also tested for their antibacterial properties. 相似文献
796.
Chain, ladder, layer, and three-dimensional metal phosphates were obtained by the reaction of amine phosphates with metal ions under mild hydrothermal conditions. The role of amine phosphates as intermediates in hydrothermal syntheses was corroborated by in situ NMR spectroscopy and X-ray diffraction studies. The picture shows a simple corner-shared linear chain structure formed in the reaction of piperazine phosphate with Zn(II) ions. 相似文献
797.
V. K. Rao I. C. Pius M. Subbarao A. Chinnusamy P. R. Natarajan 《Journal of Radioanalytical and Nuclear Chemistry》1986,100(1):129-134
A method for the precipitation of plutonium(IV) oxalate from homogeneous solutions using diethyl oxalate is reported. The precipitate obtained is crystalline and easily filterable with yields in the range of 92–98% for precipitations involving a few mg to g quantities of plutonium. Decontamination factors for common impurities such as U(VI), Am(III) and Fe(III) were determined. TGA and chemical analysis of the compound indicate its composition as Pu(C2O4)2·6H2O. Data are obtained on the solubility of the oxalate in nitric acid and in mixtures of nitric acid and oxalic acid of varying concentrations. Green PuO2 obtained by calcination of the oxalate has specifications within the recommended values for trace foreign substances such as chlorine, fluorine, carbon and nitrogen. 相似文献
798.
The oxidation by Br(V) of propan-2-ol follows the rate law (?d[Br(V)]/dt) = k4 [alcohol][Br(V)][H+]2. The initial reaction is complicated by the presence of the product bromide ion. The reaction is composed of two second order reactions—the first, a comparatively slow one and the second stage, a faster reaction which is mainly bromine oxidation. The pure bromate oxidation can be followed by the initial addition of mercuric acetate which prevents the accumulation of bromine in the system under these conditions. The reaction rate does not depend on the nature and structure of the alcohol. A mechanism involving a slow rate-determining formation of an alkyl-bromate ester followed by a fast decomposition to the products is in accord with the observed results. 相似文献
799.
Kaveri MV Prabhakaran R Karvembu R Natarajan K 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,61(13-14):2915-2918
The reactions of [RuHCl(CO)(PPh3)2(B)] (B = PPh3, pyridine or piperidine) and 2'-hydroxychalcones led to the formation of [RuCl(CO)(PPh3)(L)(B)] (L = chalconate). The new complexes have been characterized by analytical and spectral (IR, electronic, 1H NMR and 31P NMR) data. They have been assigned an octahedral structure. The complexes have been used as catalysts for the aerial oxidation of cinnamyl alcohol. Some of the complexes have been tested in vitro for growth inhibitory activity against the bacteria E. coli, S. typhi and Pseudomonas sp. and the fungi A. fumigatus. 相似文献
800.
Summary Complexes of furan and thiophene azo-oximes with iron(II), cobalt(III), nickel(II) and copper(II) have been prepared and characterised. Iron(II), cobalt(III) and copper(II) complexes are diamagnetic in the solid state. The diamagnetism of the copper(II) chelates is suggestive of antiferromagnetic interaction between two copper centres.1H n.m.r. spectral data suggest atrans-octahedral geometry for the tris-chelates of cobalt(III). Nickel(II) complexes are paramagnetic, in contrast to the diamagnetism of the analogous complexes of arylazooximes. The electronic spectra are suggestive of octahedral geometry for the iron(II), cobalt(III) and nickel(II) complexes, andD
4h
-symmetry for copper(II). Infrared data indicate N-bonding of the oximino-group to the metal ions. 相似文献