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71.
U. Narayan Bhat 《Annals of Operations Research》1987,8(1):151-164
A sequential parameter control technique previously introduced by the author is modified in this paper so as to make it simple in practice. The detailed procedure involving two phases, a warning phase with control limits and a testing phase using an appropriate test is illustrated for a queueing system with an embedded Markov chain. Operating characteristics of the procedure are also examined. 相似文献
72.
Zeitschrift für Physik A Hadrons and nuclei - 相似文献
73.
74.
The possibility of writing the repulsive energy in the Born model of binary ionic crystals as a sum of two separate contributions
from the two ions has been investigated. Such an approach leads to two identities, one connecting the lattice spacings of
a family of ionic crystals and the other connecting their compressibilities. These identities have been tested on the alkali
halide crystals over a range of pressures. The agreement is found to be quite satisfactory. Some further predictions with
respect to crystals which exist as two polymorphs have also been tested. In all cases, the deviations of the experimental
values from the exact identities can be traced to the fact that second neighbour repulsions in the crystals have been neglected.
It is hence concluded that individual compressive energies for ions in ionic crystals is a very attractive possibility. 相似文献
75.
Prompt lepton production in hadron collisions is explained in a cluster production model, by assuming that the clusters have a small branching ratio for decay into leptons. The production of low mass and small momentum clusters, normalized to reproduce pionization, can explain the observed large increases of e/π ratio for decreasing pbdT at large angles and the decreasing values of ω/π with increasing xlab near the forward direction. The present model predicts a large increase of the e/ω ratio near the forward direction as xlab increases. 相似文献
76.
D S Narayan 《Pramana》1983,21(4):233-240
The observed dependence of the yield of highpT particles on the atomic numberA of the target and the incident energy, inp-a, a-a andp-nucleus collisions, is explained in a coherent tube model. 相似文献
77.
T. V. Lakshmi Narayan C. S. Marvel 《Journal of polymer science. Part A, Polymer chemistry》1967,5(5):1113-1118
Four new polybenzimidazoles with aryl sulfone linkages between the recurring units have been prepared in order to study their thermal stability and solubility properties. The polymers prepared were high molecular weight materials with good thermal stability. 相似文献
78.
Ramesh Narayan 《Journal of Physics and Chemistry of Solids》1977,38(9):1097-1100
A formula has been derived based on a variational approach for the van der Waals dipole-quadrupole interaction coefficient between two atoms or ions. The coefficients for the various ion pairs in the alkali halides have been estimated on the basis of this formula. The results agree quite well with those estimated by Mayer (J. Chem. Phys.1, 270 (1933)) using a perturbation approach. The present formula is shown to have a practical advantage over the perturbation formula. 相似文献
79.
Das D Roy S Mitra RN Dasgupta A Das PK 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(17):4881-4889
To determine the crucial role of surfactant head-group size in micellar enzymology, the activity of Chromobacterium Viscosum (CV) lipase was estimated in cationic water-in-oil (w/o) microemulsions of three different series of surfactants with varied head-group size and hydrophilicity. The different series were prepared by subsequent replacement of three methyl groups of cetyltrimethylammonium bromide (CTAB) with hydroxyethyl (1-3, series I), methoxyethyl (4-6, series II), and n-propyl (7-9, series III) groups. The hydrophilicity at the polar head was gradually reduced from series I to series III. Interestingly, the lipase activity was found to be markedly higher for series II surfactants relative to their more hydrophilic analogues in series I. Moreover, the activity remained almost comparable for complementary analogues of both series I and III, though the hydrophilicity was drastically different. Noticeably, the head-group area per surfactant is almost similar for comparable surfactants of both series I and III, but distinctly higher in case of series II surfactants. Thus the lipase activity was largely regulated by the surfactant head-group size, which plays the dominant role over the hydrophilicity. The increase in head-group size presumably allows the enzyme to attain a flexible conformation as well as increase in the local concentration of enzyme and substrate, leading to the higher efficiency of lipase. The lipase showed its best activity in the microemulsion of 6 probably because of its highest head-group size. Furthermore, the observed activity in 6 is 2-3-fold and 8-fold higher than sodium bis(2-ethyl-1-hexyl)sulfosuccinate (AOT) and CTAB-based microemulsions, respectively, and in fact highest ever in any w/o microemulsions. 相似文献
80.
D.S. Narayan 《Nuclear Physics B》1973,59(1):299-304
Assuming Feynman's scaling law, Koba, Nielson and Olesen had shown that as s → ∞, (i) 〈nq〉/〈n〉q → dq where dq is independent of s and . The derivation of the latter result is, however, not rigorous and it does not follow, as a necessary consequence, from the scaling law. 相似文献