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531.
Azido-nitrosyl complexes and their derivatives of the types [Cr(NO)(N3)5]3? and [Cr(NO)(N3)2(L-L)] [L-L = 2,2′bipyridine (bipy) and 1,10 phenanthroline (phen)] were synthesised directly from chromate ion using hydroxylamine hydrochloride, azide ion and hydroxyl ion and other appropriate ligands virtually in a single step process in an aqueous aerobic medium. The compounds are characterised by IR, molecular weight, molar conductance, magnetic susceptibility, esr and electronic spectral data. 相似文献
532.
D. C. Ghosh A. Roychowdhury I. K. Daftari D. K. Bhattacharjee T. Roy 《Annalen der Physik》1978,490(1):15-18
The models frequently applied to estimate the target mass in high energy interactions are used in conjunction with the HEISENBERG formula to obtain a semi empirical formulation for multiplicity. It is seen that the experimental data obtained by us and other authors on multiplicity fit into that formulation when considering the initial colliding systems to be either π - p or π - π. Also the values of Cos θ (θ being the emission angle of the secondaries in lab system) averaged over all emitted particles estimated from the above formulation are in good agreement with our experimental data. 相似文献
533.
A NUT-like metric is obtained by means of a complex coordinate transformation in the Brans-Dicke theory. 相似文献
534.
Pink-brown crystalline alkali-metal trifluoromonosulphatomanganates(III), A2[MnF3(SO4)] (A = NH4, Li, Na or K), have been synthesised in high yields by reacting KMnO4 or MnO(OH) with 40% HF and A2SO4 or by the reaction of MnO(OH) with 40% HF and A2S2O8 (A = NH4 or K). The chemicallly estimated oxidation state of manganese occurs between 2.9 and 3.1, and the room temperature magnetic moments lie in the range 4.0–4.2 BM. (NH4)2[MnF3(SO4)] on being pyrolysed at 340°C yields MnSO4. 相似文献
535.
N. Bera J. K. Bhattacharjee S. Mitra S. P. Khastgir 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,46(1):41-50
We find the energy levels of a free particle confined in a two
dimensional infinite potential well having super-circular boundary
(|x|n+|y|n=an where n is a rational number and a is a
positive real number) by perturbing about the equivalent circle
(n=2). The ground state energies are very accurate over a wide
range of n and can be improved further by introducing a
phenomenological constant
determined from the knowledge of exact
results available for diamond (n=1). For excited states, we find
that the shape effect can cause parametric resonance which can lead
to singlet-triplet crossing. 相似文献
536.
Abbott B Abolins M Abramov V Acharya BS Adams DL Adams M Alves GA Amos N Anderson EW Baarmand MM Babintsev VV Babukhadia L Baden A Baldin B Balm PW Banerjee S Bantly J Barberis E Baringer P Bartlett JF Bassler U Bean A Begel M Belyaev A Beri SB Bernardi G Bertram I Besson A Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Blazey G Blessing S Boehnlein A Bojko NI Borcherding F Brandt A Breedon R Briskin G Brock R Brooijmans G Bross A Buchholz D Buehler M Buescher V Burtovoi VS Butler JM Canelli F 《Physical review letters》2001,86(10):1955-1960
We report on a study of the ratio of inclusive three-jet to inclusive two-jet production cross sections as a function of total transverse energy in p&pmacr; collisions at a center-of-mass energy sqrt[s] = 1.8 TeV, using data collected with the D0 detector during the 1992-1993 run of the Fermilab Tevatron Collider. The measurements are used to deduce preferred renormalization scales in perturbative O(alpha(3)(s)) QCD calculations in modeling soft-jet emission. 相似文献
537.
Miscibility and Molecular Orientation of Carbazole in Mixed Langmuir and Langmuir-Blodgett Films
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Md. N. Islam D. Bhattachaxjee S. A. Hussain 《中国物理快报》2007,24(7):2044-2047
We report the miscibility and molecular orientation of carbazole (CA) molecules in the mixed Langmuir and Langmuir-Blodgett (LB) films of CA in polymethyl methacrylate (PMMA) and stearic acid (SA) matrices. The lr-A isotherm confirms the formation of stable Langmuir films of CA mixed with either PMMA or SA at airwater interface. 'Characteristics of area per molecule versus molefraction and collapse pressure versus molefraction reveal complete demixing of CA and the matrix PMMA/SA molecules in the mixed films. Absorption spectroscopy certainly confirms the fact that CA molecules have preferred orientation on the substrate of the LB films. 相似文献
538.
Miscibility of Two Components in a Binary Mixture of 9-Phenyl Anthracene Mixed with Stearic Acid or Polymethyl Methacrylate at Air-Water Interface
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P. K. Paul Md. N. Islam D. Bhattacharjee S. A. Hussain 《中国物理快报》2007,24(5):1331-1334
We report the miscibility characteristics of two components in a binary mixture of 9-phenyl anthracene (PA) mixed with stearic acid (SA) or polymethyl methacrylate (PMMA). The behaviour of surface pressure versus area per molecule isotherms reveal that the area per molecule decreases systematically with increasing molefractions of PA. The characteristics of areas per molecule versus molefractions and collapse pressure vs molefraction indicate that various interactions involved among the sample and matrix molecules. The interaction scheme is found to change with the change in surface pressure and molefraction of mixing. Scanning electron microscopic study confirms the aggregation of PA molecules in the mixed films. 相似文献
539.
We report an easy solution phase template-based method to assemble mercaptoundecanoic acid-functionalized gold nanoparticles (MUA-GNPs) along poly(ethylene oxide) (PEO) chains. Transmission electron microscopy (TEM) images show one-dimensional and two-dimensional chain-like sequences of GNPs resembling PEO chains. The progress of the assembly was monitored by the evaluation of surface plasmon resonance band of MUA-GNPs with time by UV-vis spectroscopy. The assembly process is a result of hydrogen bonding interaction between the ethereal oxygen of PEO and carboxylic acid group of MUA attached to GNPs surface, which was confirmed through FTIR spectroscopy. The interaction between PEO and MUA-GNPs was further confirmed by thermal analysis using differential scanning calorimetry. 相似文献
540.
Chesta CA Mohanty J Nau WM Bhattacharjee U Weiss RG 《Journal of the American Chemical Society》2007,129(16):5012-5022
Steady-state and laser-pulsed irradiations of dibenzyl ketone (ACOB0) and derivatives with a p-methyl or a p-hexadecyl chain (ACOB1 and ACOB16, respectively) have been conducted in polyethylene films with 0, 46, and 68% crystallinities. Calculation of the fractions of in-cage combinations of the triplet benzylic radical-pair intermediates based on photoproduct yields, Fc, from ACOB16 are shown to be incorrect as a result of the kinetic consequences of drastically different diffusion coefficients for the benzyl and p-hexadecylbenzyl radicals. Careful analyses of the transient absorption traces, based upon a new model developed here, allow the correct cage effects to be determined even from ACOB0. The model also permits the rate constants for radical-pair combinations and escape from their cage of origin to be calculated using either an iterative fitting procedure or a very simple one which requires only k-CO and the intensities of the transient absorption immediately after the flash and after the in-cage portion of reaction by the benzylic radicals is completed. Values of the rate constant for decarbonylation of the initially formed arylacetyl radicals, k-CO, have been measured from the rise portions of the laser-flash transient absorption traces. They confirm the assertion from results in liquid alkane media that decarbonylation rates are independent of microviscosity. The data separate components of a reaction from an (in-cage) "cage effect" and an (out-of-cage) "persistent radical effect" that are responsible for formation of AB-type (i.e., decarbonylated) products. The effects here are a consequence of vastly different rates of diffusion for coreacting A. and B. benzylic radicals rather than segregation of the radicals in different parts of a hetereogeneous environment (which leads to an excess of AA and BB products). Heretofore, observation of exclusive formation of AB products has been attributed to in-cage combinations of geminate radical pairs. We show that not to be the case here and provide methodologies which may be used for testing the importance of the "persistent radical effect" component of reaction. 相似文献