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91.
This paper presents a study of the experimental lower boundb
L, on the root-mean-squared impact parameter of the multiparticle production in 70 GeV/c p-nucleon interaction. It has been observed that theb
L decreases with increasing final state multiplicity (n) at this fixed energy. The results are in good agreement with those of other authors.The authors would like to thank Prof. K. D. Tolostov of Dubna, U.S.S.R. for kindly supplying the exposed emulsion plates. 相似文献
92.
The problem considered here is to study the MHD effects on the steady flow of an incompressibe viscous conducting fluid through two concentric porous non-conducting infinite circular cylinders, rotating in various ways with uniform angular velocities in presence of a radial magnetic field. It is supposed that the rate of suction at the inner cylinder is equal to the rate of injection at the outer. 相似文献
93.
N.B. Manson J.T. Gourley E.R. Vance D. Sengupta G. Smith 《Journal of Physics and Chemistry of Solids》1976,37(12):1145-1148
At helium temperatures two sharp lines at 9350 and 9510 cm?1 have been observed for the first tune on the low-energy side of the broad double-peaked absorption corresponding to the transition in Fe2+ at the octahedral site in MgO. The lower energy line has a half width of 4 cm?1; Zeeman measurements show that it is of magnetic dipole origin. The Zeeman spectra are consistent with those expected for a pure electronic transition from the (5T2g)T2g ground state to the 5Eg excited state. The second line, with a halfwidth of ~ 35 cm?1, a vibrational sideband. 相似文献
94.
Psoralidin, C20H16O5 the phenolic coumarin of Psoralea corylifolia Linn. has been shown to possess two hydroxyl groups, one conjugated δ-lactone, one isopentenyl group and an intramolecular ether linkage. On systematic degradation dihydropsoralidin dimethyl ether gave 2-hydroxy-4-methoxybenzaldehyde and 2,4-dimethoxy-5-(-3-methylbutyl)-benzoic acid. The synthesis of the latter compound has been described. On the basis of the degradation experiments coupled with ultra-violet and infra-red absorption data, the structure of psoralidin has been established as 6-(3-methylbut-2-enyl)-coumestrol (IV, R = H). 相似文献
95.
Bhaskar Sengupta 《European Journal of Operational Research》1981,7(3):257-264
This paper considers a class of Markov Decision problems subjects to partial observation. We develop a methodology for early detection of failure of systems that do not display symptoms of failure. We assume that the inspections used for detection are error prone and there is a fixed probability of not detecting the failure. The problem is studied as a non-stationary, finite horizon Markovian Decision Process with two states. We demonstrate that the optimal policy has a two region structure that intuition suggests. This characterization can be used to reduce the computational burden of finding the optimum inspection schedule. We also show that the form of the optimum policy remains unchanged for the unbounded horizon problem. Finally, we discuss a potential application of the model to medical diagnosis. 相似文献
96.
High resolution gamma-ray spectra have been measured from the27Al (p,γ)28Si reaction for the resonances atE
p=2·482, 2·511 and 2·735 MeV at ϑ
pγ=0°, 30°, 55° and 90° using a Ge (Li) gamma spectrometer. From the spectra and the angular distributions the properties of
the resonance states have been obtained. These states are the isobaric analogues of the levels at 4·69, 4·75 and 4·93MeV levels
respectively in the parent nucleus A28l. 相似文献
97.
Sengupta J Mukhopadhyay R Bhattacharjya A Bhadbhade MM Bhosekar GV 《The Journal of organic chemistry》2005,70(21):8579-8582
3,5'-ether-linked pseudooligopentose derivatives were synthesized for the first time from readily available carbohydrate precursors. The 1,2-isopropylidene-protected ether-linked oligopentoses are potentially important as precursors of novel RNA analogues. Intramolecular cycloaddition of the nitrile oxides prepared from these derivatives led to the diastereoselective formation of chiral isoxazolines fused to 10-16-membered oxacycles. The stereochemistry of some of these isoxazolines was established by X-ray diffraction and NOESY analysis. 相似文献
98.
99.
The extensivity property of entropy is clarified in the light of a critical examination of the entropy formula based on quantum
statistics and the relevant thermodynamic requirement. The modern form of the Gibbs paradox, related to the discontinuous
jump in entropy due to identity or non-identity of particles, is critically investigated. Qualitative framework of a new resolution
of this paradox, which analyses the general effect of distinction mark on the Hamiltonian of a system of identical particles,
is outlined. 相似文献
100.
Unified study of the different properties of metals clearly reveals the inadequacy of the empty-core Ashcroft pseudopotential
even in the case of simple metals. In the present paper we propose a modification of the one-parameter Ashcroft pseudopotential
by assuming the parameterr
c to be wave vector-dependent. This introduces a simple modification of the electron-ion pseudopotential in the reciprocal
space. The corresponding potential in the configuration space shows that the abrupt change in the Coulomb potential atr=r
c is replaced by a continuous change spread over a small region near the core boundary. The present model has been used to
make a unified study of Al and is found to be a significant improvement over the simple Ashcroft model. The agreement between
the calculated and experimental values is found to be quite satisfactory. 相似文献