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71.
P. K. Malhotra 《Proceedings Mathematical Sciences》1965,62(4):189-212
Eight hundred and sixteen nuclear interactions produced by 4·4 GeVπ ?-mesons in nuclear emulsion have been obtained by “along the track” scanning procedure. Favourable secondary particles from a selected 290π ?-N (pion-nucleon) collisions have been identified by blob-density and multiple scattering measurements. It is found that the pion often persists in theseπ ?-N collisions, the average persistence is estimated to be 0·24 per collision. It is estimated thatπ-N andπ-π collisions account for 60% and 28% respectively of the secondary particles. The average number of charged shower particles is 〈n s〉=2·09±0·12, the average number of created charged particles is 〈n e±〉=1·94±0·12, the average number of protons with energy greater than 300 MeV is 〈n p〉=0·15±0·05 and the average number of charged kaons is found to be 〈n k±〉=0·11±0·06. The integral energy spectra of pions in C-system as well as in L-system are well represented by exponential forms. The average inelasticity of the proton in C-system is found to be 0·52±0·10. The charge retention probability for protons inπ ?-p collisions is 0·45±0·07. 相似文献
72.
R. Malhotra 《Mathematical Methods of Operations Research》1982,26(1):259-261
The present note reveals a drawback in an algorithm ofAneja/Nair [1979] for the determination of efficient solutions in a bi-criteria transportation problem with an additional time objective function and develops a modified procedure that overcomes this weakness.
Zusammenfassung In der vorliegenden Arbeit wird ein Fehlschluß im Algorithmus vonAneja/Nair [1979] zum Auffinden aller effizienten Lösungen eines Transportproblems mit zwei Summen- und einer Engpaßzielfunktion aufgezeigt. Ferner wird ein Verfahren angegeben, in dem diese Unstimmigkeiten nicht mehr auftreten.相似文献
73.
74.
S.N. Ganguli A. Gurtu P.K. Malhotra R. Raghavan A. Subramanian M. Cerrada J. Diaz J.A. Garzon R. Hamatsu L. Montanet Ch. Defoix L. Dobrzynski P. Ladron de Guevara R. Nacash P. Petitjean B. Adeva M. Aguilar-Benitez R. Pazzi 《Nuclear Physics B》1981,183(3):295-329
annihilations, leading to the production of at least one neutral K meson in the final state, have been studied in the incident momentum region of 700–760 MeV/c. Topological cross sections and cross sections for the various exclusive final states are presented. Detailed analyses of the different final states have been carried out to study the importance of resonance production and of quasi two-body and quasi three-body processes. A detailed study of the system in the four-body final states shows that the F1 meson is a spurious effect due to systematic biases. In the momentum range investigated, the C = +1 final states are strongly suppressed. 相似文献
75.
76.
77.
The photoinduced shift in the optical absorption edge and changes in the optical constants and their dispersion in the vicinity of the absorption edge (2–5 eV) have been studied in obliquely deposited thin films of Ge-chalcogenides. The variation of photo-optical changes as a function of various deposition conditions and composition throws light on the role of built-in microstructure and the relevant physical parameters necessary for the occurrence of large photoeffects. The photoinduced optical changes in 80°-films are partly (≈33%) reversible. This (reversible) part is equal to the total (completely reversible) optical changes in 0°-films. The irreversible part (≈67%) has been attributed to the observed photoinduced volume changes. The reversible optical changes have been understood in terms of configurational distortion and modifications in the electronic energy band structure, near the band edges induced by band gap irradiation. 相似文献
78.
The charge transfer from one hemisphere to the other, observed inpp-collisions is explained on the basis of a ‘mixed two component’ model, which has been proposed previously to account for
the multiplicity distribution of charged particles. Results of the calculations, based on the model, for various measurable
quantities relating to charge transfer are compared with the available experimental data. 相似文献
79.
Bhupendra Chudasama Anjana K. Vala Nidhi Andhariya R. V. Mehta R. V. Upadhyay 《Journal of nanoparticle research》2010,12(5):1677-1685
In this article, we describe a simple one-pot rapid synthesis route to produce uniform silver nanoparticles by thermal reduction
of AgNO3 using oleylamine as reducing and capping agent. To enhance the dispersal ability of as-synthesized hydrophobic silver nanoparticles
in water, while maintaining their unique properties, a facile phase transfer mechanism has been developed using biocompatible
block co-polymer pluronic F-127. Formation of silver nanoparticles is confirmed by X-ray diffraction (XRD), transmission electron
microscopy (TEM) and UV–vis spectroscopy. Hydrodynamic size and its distribution are obtained from dynamic light scattering
(DLS). Hydrodynamic size and size distribution of as-synthesized and phase transferred silver nanoparticles are 8.2 ± 1.5 nm
(σ = 18.3%) and 31.1 ± 4.5 nm (σ = 14.5%), respectively. Antimicrobial activities of hydrophilic silver nanoparticles is tested
against two Gram positive (Bacillus megaterium and Staphylococcus aureus), and three Gram negative (Escherichia
coli, Proteus
vulgaris and Shigella
sonnei) bacteria. Minimum inhibitory concentration (MIC) values obtained in the present study for the tested microorganisms are
found much better than those reported for commercially available antibacterial agents. 相似文献
80.
A logarithmic signature (LS) for a finite group G is an ordered tuple α = [A 1, A 2, . . . , A n ] of subsets A i of G, such that every element ${g \in G}$ can be expressed uniquely as a product g = a 1 a 2 . . . a n , where ${a_i \in A_i}$ . The length of an LS α is defined to be ${l(\alpha)= \sum^{n}_{i=1}|A_i|}$ . It can be easily seen that for a group G of order ${\prod^k_{j=1}{p_j}^{m_j}}$ , the length of any LS α for G, satisfies, ${l(\alpha) \geq \sum^k_{j=1}m_jp_j}$ . An LS for which this lower bound is achieved is called a minimal logarithmic signature (MLS) (González Vasco et al., Tatra Mt. Math. Publ. 25:2337, 2002). The MLS conjecture states that every finite simple group has an MLS. This paper addresses the MLS conjecture for classical groups of Lie type and is shown to be true for the families PSL n (q) and PSp 2n (q). Our methods use Singer subgroups and the Levi decomposition of parabolic subgroups for these groups. 相似文献