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1.
The study of the angular distribution of slow particles during high energy hadron-nucleus interaction indicates that emission of slow particles takes place from a thermally non-equilibrated system. This evidence has come out from the presence of intermittency - a phenomenon that reveals a fractal structure and represents a self-similarity in the particle production process. Hence, this study highlights inadequacy of cascade-evaporation model and advocates the need of its refinement. 相似文献
2.
For the NO molecule, modelled as a Morse oscillator, time-dependent (TD) nuclear Schr?dinger equation has been numerically
solved for the multiphoton vibrational dynamics of the molecule under a far-infrared laser of wavelength 10503 nm, and four
different intensities,I = 1 × 108, 1 × 1013, 5 × 1016, and 5 × 1018 W cm−2 respectively. Starting from the vibrational ground state at zero time, various TD quantities such as the norm, dissociation
probability, potential energy curve and dipole moment are examined. Rich high-harmonics generation (HHG) spectra and above-threshold
dissociation (ATD) spectra, due to the multiphoton interaction of vibrational motions with the laser field, and consequent
elevation to the vibrational continuum, have been obtained and analysed.
Dedicated to Professor C N R Rao on his 70th birthday
An erratum to this article is available at . 相似文献
3.
Dipak Ghosh Madhumita Lahiri Argha Deb Susobhan Das Krishnadas Purkait Biswanath Biswas Jayanta Roy Choudhury Rini Chatterjee Abdul Kayum Jafry 《Zeitschrift fur Physik C Particles and Fields》1996,71(1):243-249
The scaled factorial moments and the multifractal moments have been investigated in differentη-intervals to study the dynamical fluctuation of pions produced in 200 AGeV32S-Ag/Br interaction. In order to investigate the detail characteristics of intermittency behaviour, theF-moments are extracted up to the eighth order of moments in differentM-intervals. The analysis indicates a non-thermal phase transition and different regime of particle production during the hadronisation process. 相似文献
4.
Kinetics of the copolymerisation of styrene and maleic anhydride have been studied in dioxane at 50° using azobisisobutyronitrile as initiator. Explanation of the kinetic behaviour has been attempted in terms of the participation in propagation of a charge-transfer complex between the monomers along with propagation via free monomers. It is found that the complex model is able to explain most features of the copolymerisation of these monomers. It has been possible to determine the constants δ1, δ2, k1c/k12, k2c/k21 and Φ where k1c/k12 and k2c/k21 represent the specific rate constants of reaction of a particular type of radical with a dissimilar monomer site of the complex relative to that with a dissimilar free monomer. They are reviewed on the basis of available literature data. The cross-termination factor Φ is found to play an important role in the present system. An approximate value of for maleic anhydride could also be found and this probably represents the first reported value for this constant from copolymerisation. The applicability of the generalised penultimate model is also briefly discussed. 相似文献
5.
An efficient and practical one-pot method for the synthesis of novel diversified sugar derived dihydro-quinazolino[4,3-b]quinazolin-8-ones has been reported. Various protected sugar hemiacetals were used to synthesize the hybrid tetracyclic ring system. The one-step reductive transformation of 2-(2-nitrophenyl)-3H-quinazolin-4-one with different sugar hemiacetals furnished the desired tetracyclic product in good yields and with high purity. 相似文献
6.
N-Hydroxy-N-m-tolyl-N′-(2-methyl-5-chloro)phenyl-p-toluamidine hydrochloride (HTMCPTH), a monobasic and bidentate chelating agent which reacts with vanadium(V) in carboxylic acid media to develop a blue-violet complex, has been employed as a highly selective reagent for extraction and direct photometric determination of the metal. Solvent extraction experiments indicate that from aqueous acetic acid (1.0–10.0 M), monochloroacetic acid (0.1–10.0 M), and phenylacetic acid (at pH 0.5–6.0) vanadium(V) is quantitatively extracted into chloroform. Almost all common ions including Fe3+, Cu2+, Ni2+, Co2+, Mn2+, Cr3+, Ti4+, Zr4+, and Mo6+ do not interfere with the proposed method. The procedure has been utilized for accurate determination of vanadium in standard steels. 相似文献
7.
Using a very simple trial function and unperturbed electron densities calculated by a new procedure, the frequency-dependent dipole polarizability () of Ne, Ar, Kr and Xe has been calculated in the range 0 0.45 a.u., by a Karplus-Kolker-type variation-perturbation method. Results progressively worsen for larger systems so that, for Xe, (0) is only 75% of the experimental value. Probable reasons for this are discussed. 相似文献
8.
The reaction of 2-arylpyridinecarboxaldimine [RH4C6NC(H)Py, L (1)] with hydrated RuX3 (X = Cl, Br) in boiling C2H5OH affords dark crystals of RuX2L2. Two geometrical isomers of the compound have been isolated and characterized by analytical and spectroscopic data. The trans isomer of RuCl2L2 shows a single sharp band for ν(Ru---Cl), whereas two bands are observed for the corresponding cis isomer. The highresolution 1H NMR spectra of the isolated complexes are reported and completely assigned. All the complexes have multiple t2→π*(L) transitions in the visible region. Each of the complexes display a quasi-reversible oxidative response due to an RuIII/RuII couple in the range 0.25–0.40 V vs S.C.E. at a platinum working electrode. The formal potentials of this couple obey the Hammett relationship. The ligand-based irreversible oxidations are also briefly noted. 相似文献
9.
Analytical properties of hydrogen-like atomic orbitals (HAO ) that are used in the MOLCAO approach to the quantum theory of molecules have been studied. Addition and expansion theorems for HAO have been proved, both in coordinate and momentum representations. A close relation has been established between HAO and the reduced Bessel functions of half-integer indices. New methods are suggested to calculate integrals for atomic and molecular form factors, and multicenter integrals, for the HAO basis in the MO LCAO theory. 相似文献
10.
Thermal noise in Hg0.795Cd0.205Te detectors is estimated for large biasing fields at a lattice temperature of 77 K, by computing the correlation functions of the velocity fluctuations with the Monte Carlo technique. The noise temperature for current components transverse to the field is almost independent of the field, but that corresponding to the parallel component increases by a factor of about 1.3 at 50 V/cm and by a factor of 3.0 at 300V/cm. The thermal noise voltage for a detector of 85 resistance increases from 0.6nV/Hz1/2 at low biasing fields to about 3nV/Hz1/2 at a field of 300 V/cm. The noise power is also found to remain constant up to about 75 GHz, and it decreases thereafter by a factor of 0.25 for doubling of the frequency. 相似文献