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221.
Earlier results for the moments of the number distribution are extended to finite but very small thicknesses. These results are compared with the available experimental data in emulsions. The effect of ionisation loss on the number distribution for infinite thickness is also estimated and finally some mathematical features which establish the equivalence of the different methods of theoretical approach are dealt with. 相似文献
222.
An analysis of a linearly tapered inhomogeneous channel junction field-effect transistor (JFET) is presented leading to a closed-form solution for the current-voltage characteristics and the modified FET parameters. Operational improvement for the inhomogeneous FET is shown directly from a comparison with the solution for a homogeneous channel FET. 相似文献
223.
According to Order-Disorder Model (ODM), in the early stages of fission, the charges in a fissioning nucleus gets polarised
into two impending parts along with corresponding most stable neutrons which are calculated from the minimum in isobaric mass
parabola. This polarisation into two most stable configuration leaves a small number of neutrons as balance neutrons i.e.N
bal. The distribution of theseN
bal for various polarisation modes, shows a very profound correlation with the yield distribution. Judging from this striking
correlation between these two distributions, it can be predicted that the asymmetry in fission decreases gradually and ultimately
disappear for nuclei havingZ ⋍ 102 but reappears again for the nuclei in super heavy region. 相似文献
224.
We have analyzed the ability of a tertiary amide group to activate an ortho position on aromatic system toward an electrophilic attack using an ab initio SCF molecular orbital method. The molecular electrostatic potential was used to analyze the electronic nature of the ortho-lithiated intermediate complex and possible sites for electrophilic attack. 相似文献
225.
A. U. Bhanu P. C. Kalsi S. Sahoo R. H. Iyer 《Journal of Radioanalytical and Nuclear Chemistry》1988,121(1):29-43
The paper describes the results and observations on the analyses of uranium in calcium fluoride slag, silica cake and fused salt cake obtained in uranium metal and fuel plants. The analysis is done by (1) non-destructive assay by passive gamma ray counting, (2) chemical analysis, and (3) solid state nuclear track detector (SSNTD) technique. The details of the development of NDA method to suit the requirements of the sample are given. The difficulties encountered in chemical assay are described. SSNTD method has been applied to such materials for the estimation of the uranium for the first time. A simple scheme for the recovery of uranium and the salt mixture from the fused salt cake is also described. 相似文献
226.
Jayabalan J. Leong O.B. Seng L.M. Iyer M.K. 《Microwave and Wireless Components Letters, IEEE》2004,14(5):216-218
A scaling technique for partial element equivalent circuit (PEEC) analysis using SPICE is introduced in this letter. The perturbation series based scaling is applied to the component values extracted by the standard PEEC method to get up to an order of magnitude improvement in relative accuracy of scattering parameters with SPICE simulation. The effectiveness of the technique is verified by using the numerical example of a stripline structure and comparing the results with that of the method of moments (IE3D). 相似文献
227.
Jaya N. Iyer 《manuscripta mathematica》2003,111(3):277-285
In this note we give an example of an indecomposable higher Chow cycle on a special family of quartics in ℙ3. The example is obtained as an extension of a cycle in the higher Chow group CH
2
(K,1) of a singular Kummer surface.
Received: 19 June 2002 / Revised version: 17 October 2002
Published online: 24 April 2003
Mathematics Subject Classification (2000): 14C15, 14C25, 14H10, 14H28, 14F42 相似文献
228.
Solitons are simulated in an anharmonic linear lattice that is susceptible to a soft mode instability. The soft mode characteristic
is introduced in the system by the addition of a term (−Au
n
2
) in the potential between the neighbouring atoms and the evolution of the system is studied as the soft mode parameterA varies from zero to the square of the limiting optical frequency. It is shown that the displacement pattern of the system
shows three regions. First there is a region in which the relative displacements of the atoms show large amplitude oscillations.
This is followed successively by a domain in which the relative displacements of the atoms are negligible and then by the
soliton itself. In the soft mode region, the displacements of the atoms preceding the soliton decrease drastically in a linear
fashion first, parabolically next and later become steady. It further exhibits a kind of devil’s stair cases. 相似文献
229.
230.
Molecular modeling of stationary phases presents a unique challenge because there is little available experimentally derived structural information. Verified interaction mechanisms at a molecular level with analytes are also rare. Molecular mechanics calculations using the Tripos force field were carried out to qualitatively and quantitatively assess stationary phase interactions. Binding energy values of -15.40, 15.28, -12.53, and -12.34 kcal/mol, respectively, are obtained for olanzapine (OLZ), OLZ-D3, des-methyl olanzapine (DES), and DES-D8 that corresponded to the retention behavior of the four compounds observed using liquid chromatography-mass spectrometry (MS)-MS. The model explains, semiquantitatively, the deuterium isotope effect in the normal-phase chromatographic separation of these compounds. 相似文献