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排序方式: 共有224条查询结果,搜索用时 31 毫秒
31.
M. Deutschmann R. Honecker K. Rumpf U. Kundt M. Walter U. Idschok R. Hartmann V.T. Cocconi T. Coghen S. Humble A. Kotański D.R.O. Morrison J. Figiel A. Guła P. Malecki B. Muryn L. Suszycki E. Leitner 《Nuclear Physics B》1975,85(1):31-38
The differential cross section for the charge-exchange process π+p → π0 (π+p) at 8, 16 and 23 GeV/c is presented for several regions of the π+p effective mass. It is found that the dip at t′ ≈ 0.6 (GeV/c)2 which is observed in the Δ(1236) mass band becomes a less pronounced structure in the higher mass regions. However, while the slope of the distributions in the near-forward direction decreases strongly with increasing π+p mass, there is no evidence that the observed structure moves to higher values of t′ as the π+p mass increases. These results are consistent with a Regge-exchange picture where the position of the dip is determined by the exchanged trajectory, but are inconsistent with a simple geometrical picture. 相似文献
32.
V K B Kota 《Pramana》1977,9(2):129-140
The single particle SU(3) parentage coefficients are calculated for the case of leading SU(3) representation in the highest
orbital symmetry partition, using the method suggested by Hecht. Tabulations are given for all possible cases of identical
nucleons in η=3 and η=4 shells. 相似文献
33.
A quasiadiabatic nonfocusing transition-energy crossing is proposed for suppressing any nonadiabatic and undesired features in a longitudinally separated function-type accelerator, in which particles are confined by an radio-frequency voltage with an adiabatic reduction of the amplitude and accelerated by a step voltage. This new method has been examined, both theoretically and experimentally. 相似文献
34.
AbstractWe consider a new two-scale problem which is given as a mathematical model for moisture transport arising in a concrete carbonation process. In research for moisture transport, it is a crucial step how to describe the relationship between the relative humidity and the degree of saturation, mathematically. Here, we have proposed the two-scale model consisting of the diffusion equation for the relative humidity in a macro domain and the free boundary problems describing the relationship in infinitely micro domains. Accordingly, the structures of the micro domains are unknown in our model. This is a significant feature of our new model to emphasize. The aim of this paper is to establish local existence in time and uniqueness of a solution to the model. 相似文献
35.
Dr. Bozheng Sun Dr. Meagan S. Oakley Dr. Kota Yoshida Yanwen Yang Prof. Matteo Tommasini Dr. Chiara Zanchi Dr. Andrea Lucotti Dr. Michael J. Ferguson Dr. Frank Hampel Prof. Mariusz Klobukowski Prof. Rik R. Tykwinski 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(38):e202200616
Cyclic tetraaryl[5]cumulenes ( 1 a–f ) have been synthesized and studied as a function of increasing ring strain. The magnitude of ring strain is approximated by the extent of bending of the cumulenic core as assessed by a combination of X-ray crystallographic analysis and DFT calculations. Trends are observed in 13C NMR, UV-vis, and Raman spectra associated with ring strain, but the effects are small. In particular, the experimental HOMO-LUMO gap is not appreciably affected by bending of the [5]cumulene framework from ca. 174° (λmax=504 nm) in 1 a to ca. 178° (λmax=494 nm) in 1 f . 相似文献
36.
H. H. Willard J. J. Thompson E. Kasper P. Slawik A. W. Middleton K. Seelkopf H. Taeger P. Schmidt F. Weyrauch A. Necke H. Müller A. J. Lindsey B. Park E. J. Lewis O. B. Winter Helen M. Robinson F. W. Lamb E. J. Miller C. E. Willoughby E. S. Wilkins E. O. Kraemer A. Jílek J. Kota 《Analytical and bioanalytical chemistry》1936,106(4-6):200-207
37.
Kota Uriya 《Journal of Evolution Equations》2016,16(1):173-191
We consider the asymptotic behavior of a solution to a system of quadratic nonlinear Schrödinger equations with three wave interaction in two dimensions. We construct a particular solution which has a mass transition phenomenon among three components periodically in time. This is based on the analysis for a system of ordinary differential equations which approximates the solution of the system of nonlinear Schrödinger equations. 相似文献
38.
Onodera K Hirano-Iwata A Miyamoto K Kimura Y Kataoka M Shinohara Y Niwano M 《Langmuir : the ACS journal of surfaces and colloids》2007,23(24):12287-12292
Here, we propose a label-free detection of protein-protein interactions that enables simultaneous qualitative analysis of target proteins by using Fourier transform infrared (FTIR) absorption spectroscopy in multiple internal reflection geometry (MIR-FTIR). Using this method, the target proteins were detected based on the peak height of the amide I and amide II bands, while discrimination of specific and nonspecific signals is made based on the secondary structure of the analytes, which is determined through second-derivative analysis of the amide I band. As a model system, an antigen peptide was immobilized on the surface of GaAs, which was transparent to mid-infrared light, and the interaction with its antibody was examined in aqueous media. We demonstrated that the binding of the antibody to the antigen immobilized on a GaAs surface selectively gave rise to beta-sheet amide I vibrations (1639 and 1690 cm-1), while no structurally related signals were induced by nonspecifically adsorbed proteins. The peak height of the beta-peak (1639 cm-1) in the amide I band linearly increased with the antiserum concentration as well as that of the amide II band. The detection limit (S/N = 3) was a 1:36 000 dilution for the amide I signal. In addition, through the use of surface-sensitive MIR-FTIR, the present sensor selectively detected the antigen-antibody interactions at the surfaces without being affected by the presence of bulk species, enabling rapid and wash-free detection. Our method provides not only rapid label-free detection of protein-protein interactions but a more accurate discrimination between specific and nonspecific interactions through the use of the secondary structure of the target proteins as a measure for the specific signals. 相似文献
39.
A specific HPLC method for the simultaneous determination of YM928, a novel noncompetitive AMPA receptor antagonist, and its demethylated metabolite (YM-58875) in rat, dog and monkey plasma was developed and validated. The method utilized multiple-step liquid-liquid extraction followed by a reversed-phase HPLC with UV detection at 275 nm. No interfering peaks were observed at the retention times of YM928, YM-58875 or internal standard. The validated quantitation range was 5-5000 ng/mL for both YM928 and YM-58875 when 1 mL of the plasma sample was used. The intra- and inter-day precision was less than 5.3 and 2.5% for YM928, and 3.7 and 2.3% for YM-58875, respectively. The intra- and inter-day accuracies were -8.7-5.3% and 0.7-1.9% for YM928, and -10.0-6.1% and 1.3-3.4% for YM-58875, respectively. The mean recoveries in the extraction process were 52.7-62.8%. The utility of this analytical method was demonstrated by the investigation of the pharmacokinetics of the unchanged drug and its metabolite in preclinical studies. 相似文献
40.