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101.
Yu. V. Torubaev A. A. Pasynskii P. Mathur 《Russian Journal of Coordination Chemistry》2008,34(11):799-804
A reaction of the tetramer [PhTeI]4 with Fe(CO)5 gave the monomeric complex (CO)3FeI2(Ph2Te2) (I) containing a diphenyl ditelluride molecule linked with cis-tricarbonyldiiodoiron. According to X-ray diffraction data, the Fe-Te distance in complex I (2.5724(6) ?) is appreciably shorter than the sum of the covalent Fe and Te radii and the Te-Te bond (2.7705(5) ?) is only
slightly longer than that in free Ph2Te2 (2.705(1) ?). In the reaction of Fe(CO)5 with PhTeI3, a complex with PhTeI as a ligand to the transition metal atom was obtained for the first time. Unlike free PhTeI, the resulting
complex (CO)3FeI2(PhTeI) (II) is stable in air at room temperature for several days. According to X-ray diffraction data, the ligand PhTeI (Te-C 2.126(4)
?, Te-I(3) 2.7548(5) ?) is stabilized by the coordination of tellurium to both the iron (Te-Fe 2.5451(6) ?) and iodine atoms
(Te(1)-I(1) 3.1634(5) ?). The latter coordination probably involves the vacant d orbital of tellurium and the lone electron pair on the iodide ligand.
Original Russian Text ? Yu.V. Torubaev, A.A. Pasynskii, P. Mathur, 2008, published in Koordinatsionnaya Khimiya, 2008, Vol.
34, No. 11, pp. 807–811. 相似文献
102.
Upadhyay SK Tehlan S Mathur P 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2007,66(2):347-352
A new benzimidazole-based diamide ligand-N,N'-bis(alanine-2-benzimidazolyl) hexanediamide (ABHA) has been synthesized and utilized to prepare Cu(II) complexes of general composition [Cu(ABHA)X2].nH2O,where X is an exogenous anionic ligand (X=Cl-,NO3-). Low temperature EPR spectra has been obtained that shows gparallel>gperpendicular>2.0024, indicating a tetragonal geometry in the solution state. The complexes display a quasi-reversible redox wave due to the Cu(II)/Cu(I) reduction process. E1/2 values shift anodically as NO3-相似文献
103.
We experimentally probe molecular ionization and dissociation of methane molecules in the gas phase upon their irradiation by intense pulses of white light that spans the wavelength range 500-850 nm. White light pulses are generated upon irradiation of BK7 glass by 36-fs-long pulses of intense 820 nm laser light. Comparison is made of the molecular fragmentation patterns obtained using white light that is depolarized with those obtained using single-color (820 nm) light that is highly chirped. On the basis of such comparison, we make hitherto-unavailable estimates of the in situ intensity of white light pulses. Results obtained using white light also indicate that resonances apparently do not play any role in the ionization dynamics that ensue upon irradiation by intense, broadband light; neither are the dynamics affected by the polarization properties of the 820 nm light that is used to generate the white light. 相似文献
104.
V. T. Aher M. M. Palrecha A. V. Kulkarni G. C. Shah P. K. Mathur 《Fresenius' Journal of Analytical Chemistry》1999,364(4):362-364
A differential pulse voltammetric (DPV) method is proposed for the determination of palladium in deoxo catalysts, which are
used in recombination units of the cover gas system of nuclear reactors. The electrode system consists of hanging mercury
drop electrode (HMDE)/ platinum auxillary/ Ag-AgCl reference electrode. The supporting electrolyte consists of 0.02 M diammonium
tartrate + 0.08 M ammonia-ammonium chloride buffer at pH 9.0. Fe, Cu, Pb, Ni, Co and Zn did not interfere. The interference
by Cd could be eliminated using 0.005 M EDTA. The relative standard deviation of the proposed method was about 4.0% at ∼ 0.5%
palladium content in the catalyst. The method is simple, rapid and free from any possible interferences.
Received: 8 December 1998 / Revised: 11 January 1999 / Accepted: 18 January 1999 相似文献
105.
M. S. Alam A. A. S. Awwal P. McWhorter R. Venkatesh S. Mathur M. Dugar B. Grewal 《Optics & Laser Technology》2000,32(4)
A new synthetic discriminant-function-based amplitude modulated phase-only filtering technique is proposed for scale invariant pattern recognition. This technique has been found to yield improved correlation output when compared with the alternate techniques. The proposed technique is inherently suitable for optical implementation using the currently available spatial light modulators. Simulation results confirm the effectiveness of the proposed technique. 相似文献
106.
H-atoms in C2H5OH are rearranged by strong optical fields generated by intense, 100 fs long infrared laser pulses to form new bonds that lead to the H 3 + molecular ion. This observation appears to be against the expectation that exposure of molecules to intensities of the order of 1015 W cm?2 inevitably lead to multiple ionization of molecules followed by instantaneous Coulomb explosion into fragments. The polarization dependence of the H 3 + signal and of the energy content of H 3 + ions lead to believe that H-atom rear-rangement in ethanol occurs within a single 100 fs pulse. 相似文献
107.
S. P. Purohit K. C. Mathur 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2009,54(2):173-177
In this paper we report a study on the elastic scattering of electrons by lithium and sodium atoms in the presence of circularly
polarized resonant laser field within the framework of the two-state rotating wave approximation. The effect of laser on projectile
electrons is described by Volkov states. The frequency of the laser field is chosen to match with the 2s–3p (3s–3p) transition
frequency in lithium (sodium) atoms. The total and differential elastic cross sections with single photon exchange are calculated
for intermediate energies (50–150 eV) and laser intensity (107–1011 W cm-2).
An erratum to this article can be found online at http://dx.doi.org/.
An erratum to this article can be found at 相似文献
108.
Asmita Mukherjee R. Basu H. Dahiya L. Gamberg R. Godbole S. Gupta M. C. Kumar L. Magnea P. Mathews N. Mathur A. Mukherjee P. J. Mulders V. Ravindran A. Tripathi 《Pramana》2009,72(1):277-283
This is the report of the QCD working sub-group at the Tenth Workshop on High Energy Physics Phenomenology (WHEPP-X).
相似文献
109.
Shubhra Mathur Rishi Vyas Rohit Jain Praveen Kumar K. Sachdev S.K. Sharma 《Journal of Non》2011,357(16-17):3084-3087
Potentiodynamic polarization studies were carried out on nanocrystalline I, nanocrystalline II and nanocrystalline III states having crystallite size 35 ± 5 nm, 18 ± 2 nm and 10 ± 2 nm of the alloy Ti60Ni40 in 1 M H2SO4 aqueous medium. It was observed that the nanocrystalline III state exhibits superior corrosion resistance as compared to the nanocrystalline II and nanocrystalline I states of the alloy Ti60Ni40. XPS studies were also performed after corrosion test and it was observed that nanocrystalline III state contains only Ti2+ and Ti4+ species whereas nanocrystalline I and nanocrystalline II state contains Ti2+, Ti3+and Ti4+ along with some unoxidized metallic Ti0 in the case of nanocrystalline I state. Thus the small crystallite size and the presence of only Ti2+ and Ti4+ species in the form of TiO and TiO2 leads to the formation of a protective oxide film which is adherent, stable and improves the corrosion resistance of the nanocrystalline III state of the alloy Ti60Ni40. 相似文献
110.
Adsorption of Safranin-T from wastewater using waste materials- activated carbon and activated rice husks 总被引:6,自引:0,他引:6
Gupta VK Mittal A Jain R Mathur M Sikarwar S 《Journal of colloid and interface science》2006,303(1):80-86
Textile effluents are major industrial polluters because of high color content, about 15% unfixed dyes and salts. The present paper is aimed to investigate and develop cheap adsorption methods for color removal from wastewater using waste materials activated carbon and activated rice husk-as adsorbents. The method was employed for the removal of Safranin-T and the influence of various factors such as adsorbent dose, adsorbate concentration, particle size, temperature, contact time, and pH was studied. The adsorption of the dye over both the adsorbents was found to follow Langmuir and Freundlich adsorption isotherm models. Based on these models, different useful thermodynamic parameters have been evaluated for both the adsorption processes. The adsorption of Safranin-T over activated carbon and activated rice husks follows first-order kinetics and the rate constants for the adsorption processes decrease with increase in temperature. 相似文献