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181.
Karasch Christian Popovic Milan Qasim Mohamed Bajpai Rakesh K. 《Applied biochemistry and biotechnology》2002,98(1-9):1173-1185
Data for alkali hydrolysis of 2,4,6-trinitrotoluene (TNT) in aqueous solution at pH 12.0 under static (pH-controlled) as well
as dynamic (pH-uncontrolled) conditions are reported. The experiments were conducted at two different molar ratios of TNT
to hydroxyl ions at room temperature. The TNT disappeared rapidly from the solution as a first-order reaction. The complete
disappearance of aromatic structure from the aqueous solution within 24 h was confirmed by the ultraviolet-visible (UV-VIS)
spectra of the samples. Cuvet experiments in a UV-VIS spectrophotometer demonstrated the formation of Meisenheimer complex,
which slowly disappeared via formation of aromatic compounds with fewer nitro groups. The known metabolites of TNT were found
to accumulate only in very small quantities in the liquid phase. 相似文献
182.
183.
The paper presents, in an abbreviated form, the results of some measurements which were carried out with the aim to obtain an efficient and stable performance of a helium gas-flow CEMS detector. 相似文献
184.
The crystal structure of the cyclopentadienyl vanadocene complex (η5‐C5H5)2V(N3)2 was determined. The molecule has a typical bent metallocene structure in which two η5‐bonded cyclopentadienyl rings and two nitrogen atoms of azide ligands occupy the pseudotetrahedral coordination sites around the vanadium(IV) center. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
185.
Milan Marčič 《International Journal of Theoretical Physics》1997,36(5):1199-1207
We deal with photon-electron scattering which occurs between two uncharged conducting parallel plates moving away from each
other at a constant velocity. The electromagnetic vacuum field between two plates is defined by the configuration of space
and also interacts with the electrons. We show the relevant operators for both the electron and photon fields and the computation
of the corresponding Feynman propagator,S-matrix, and scattering cross section, taking into account the influence of the changeable vacuum field. Correction terms
in the computedS-matrix and scattering cross section manifest the influence of the changeable vacuum field. We analyze an example for low-energy
scattering of the influence of the changeable vacuum field upon the scattering cross section. 相似文献
186.
The crystal structure of the first cyclopentadienyl vanadium(IV) pseudohalide complex, (η5‐C5H4CH3)2V(NCO)2, was determined. The molecule has a typical bent metallocene structure in which two η5‐bonded methyl‐cyclopentadienyl rings and two nitrogen atoms of cyanato ligands occupy the pseudotetrahedral coordination sites around the vanadium(IV) center. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
187.
Dipankar Mishra Subhendu Naskar Shyamal K. Chattopadhyay Milan Maji Parbati Sengupta Rupam Dinda Saktiprasad Ghosh Thomas C. W. Mak 《Transition Metal Chemistry》2005,30(3):352-356
The synthesis, crystal structure, redox and spectroscopic properties of trans-[Ru(bbpH2)(PPh3)2Cl]Cl are reported. In the crystalline solvate trans-[Ru(bbpH2)(PPh3)2cCl]Cl CHCl3 H2O, the molecular components are connected by strong intermolecular hydrogen bonding to form an infinite double column. 相似文献
188.
V. T. Baranov S. Bellucci V. M. Biryukov G. I. Britvich C. Balasubramanian V. Guidi G. Giannini V. N. Zapolsky V. I. Kotov A. E. Kushnirenko V. A. Maisheev G. Martinelli E. Milan V. A. Pikalov V. I. Terekhov U. Uggerhoj V. N. Chepegin Yu. A. Chesnokov 《JETP Letters》2005,82(9):562-564
Radiation emitted by positrons moving in a periodically deformed crystal has been experimentally observed for the first time. Radiation spectra have been measured in a wide energy range. Experimental evidence has been obtained for an undulator peak in a radiation spectrum, which is qualitatively consistent with calculations. Crystalline undulators ensure an equivalent magnetic field of 1000 T and a period in the submillimeter range and can therefore be used to generate x-ray and gamma radiation that is a hundred times harder than radiation in usual undulators. 相似文献
189.
This paper reports the investigation of the nanostructured surface morphology of novel arborescent polyisobutylene-block-polystyrene (PIB-PS) copolymers, in comparison with linear PS-PIB-PS triblock copolymers, using atomic force microscopy (AFM) in tapping mode. Arborescent PIB-PS samples displayed interesting new phase morphologies, which changed dramatically upon annealing but remained irregular. Linear PS-PIB-PS samples showed morphologies similar to those previously found by transmission electron microscopy (TEM) in cryomicrotomed bulk samples, ranging from spherical/cylindrical to lamellar nanometer-sized discreet PS phases dispersed in a continuous PIB matrix. Annealing the samples resulted in more ordered structures.Three-dimensional AFM image and section analysis indicated a height difference between PIB and PS in the block copolymers, which became more prominent during annealing. This feature was verified on compression moulded and protein coated samples. The arborescent PIB-PS materials displayed thermoplastic elastomeric behaviour with a tensile strength between 7 and 10 MPa and elongation ranging from 1000% to 1830%. In comparison, linear triblock samples had a tensile strength between 7 and 20 MPa and elongation ranging from 380% to 640%. Block copolymers with irregular elastomeric midsegments may emerge as a new class of TPEs. 相似文献
190.
A. Vermogen E. Picard M. L. Milan K. Masenelli‐Varlot J. Duchet G. Vigier E. Espuche J. F. Gérard 《Journal of Polymer Science.Polymer Physics》2008,46(18):1966-1975
Semi‐crystalline polymer‐clay nanocomposite properties are often considered only by their clay dispersion state. The purpose of this work is to highlight texture effects on semi crystalline polymer‐clay properties. Maleic anhydride‐grafted polyethylene nanocomposites with two different processing techniques (Blown Extrusion and Compression) were studied. The processing was shown to induce different crystalline lamellae orientation in the films but with no significant changes in the crystalline lamellae long period, degree of crystallinity, clay particle orientation morphology and dispersion. The impact of these specific textures on the nanocomposites barrier and tensile properties were reported. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1966–1975, 2008 相似文献