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排序方式: 共有457条查询结果,搜索用时 46 毫秒
41.
Ahmed Abouelaz Enrico Casadio Tarabusi Abdallah Ihsane 《Mediterranean Journal of Mathematics》2009,6(3):303-316
We study the Radon transform R on the discrete Grassmannian of rank-d affine sublattices of Z
n
for 0 < d < n, extending and building on previous work of the first- and third-named authors in codimension 1. By analogy with the integral
geometry on Grassmannians in R
n
, various natural questions are treated, such as definition and properties of R and its dual transform R
*, function space setting, support theorems and inversion formulas. 相似文献
42.
John P. Shockcor Ronald C. Crouch Gary E. Martin Abdallah Cherif Jiann-Kuan Luo Raymond N. Castle 《Journal of heterocyclic chemistry》1990,27(2):455-458
One-dimensional ( 1D ) variants of two-dimensional ( 2D ) nmr techniques can frequently provide the required information in a much shorter period of time than the 2D experiment from which they were derived. Application of the 1D homonuclear Hartmann-Hahn (1D-HOHAHA) experiment to establish proton-proton connectivity networks in highly overlapped four-spin systems in the proton nmr spectra of polynuclear aromatics is described. Selective subspectra are contrasted to the data obtained in a COSY experiment on the same molecule, benzo[f][l]benzothieno [2,3 -c]quinoline. Results from the 1D-HOHAHA technique are especially useful when component resonances from several spin systems are heavily overlapped. Relayed 1D-HOHAHA provides the means of exploiting small, long range coupling pathways of polynuclear aromatics. 相似文献
43.
Turky Abdallah Bayoumi Ashraf H. Sherbiny Farag F. El-Adl Khaled Abulkhair Hamada S. 《Molecular diversity》2021,25(1):403-420
Molecular Diversity - The discovery of potent STAT3 inhibitors has gained noteworthy impetus in the last decade. In line with this trend, considering the proven biological importance of... 相似文献
44.
Abstract
The effect of Ni2+ cation, imidazole, and mixtures of them on the corrosion behavior of carbon steel in 0.5 M H2SO4 solution was studied by using galvanostatic polarization, potentiodynamic anodic polarization, and weight-loss techniques. Ni2+ cation, imidazole, and mixtures of them provide a good protection to carbon steel against pitting corrosion in chloride-containing solutions. The inhibiting solutions were analyzed by using UV–Vis spectrophotometry. The inhibition was explained on the basis of formation of a complex between the two components. The inhibition mechanism was discussed in terms of the results derived from corrosion and UV–Vis spectrophotometric measurements as well as conductometric investigations. 相似文献45.
Theoretical methods have been employed to investigate the structural, spectroscopic and energetic properties of difluoro(germylthio)phosphine in the Cs symmetry in the gas phase. The levels of theory used are MP2 and DFT/B3LYP and the basis set used for all atoms is 6-311G(d,p). The computed structural parameters, namely, bond lengths and bond angles and spectroscopic parameters, namely, infrared frequencies, Raman activities and NMR chemical shifts have been compared with experimental data reported in literature. The structure of this compound has been analysed using natural bond orbital approach. Both the ab initio methods perform satisfactorily when the predicted and experimental parameters are compared. We have extended this study, using the same methods and basis set, to the selenium analogue, namely, difluoro(germylseleno)phosphine for which literature is elusive. The MP2/6-311G(d,p) geometrical parameters for difluoro(germylseleno)phosphine are: r(P–Se) = 2.270, r(Ge-Se) = 2.386, r(P–F) = 1.604, r(Ge–H) = 1.530 Å, ∠(Ge–Se–P) = 91.4, ∠(F–P–F) = 96.7, ∠(Se–P–F) = 99.9 and ∠(Se–Ge–H) = 109.5°. Apart from these, we have also studied the energetic parameters for their synthesis. The results indicate that formation of the sulphur-containing compound is favoured thermodynamically. 相似文献
46.
Kamel Khimeche Abdallah Dahmani Ilham Mokbel 《The Journal of chemical thermodynamics》2010,42(7):829-833
The vapour pressures of liquid {3-diethylaminopropylamine (3-DEPA) + cyclohexane} were measured by a static method between T = (273.15 and 363.15) K at 10 K intervals. The excess molar volumes VE at 298.15 K and excess molar enthalpies HE at 303.15 K were also measured. The molar excess Gibbs free energies GE were obtained with Barker’s method and fitted to the Redlich–Kister equation. The Wilson equation was also used. Deviations between experimental and predicted GE and HE, by using DISQUAC model, were evaluated 相似文献
47.
Search for a standard model Higgs boson in the H→ZZ→ℓ(+)ℓ(-)νν decay channel with the ATLAS detector
Aad G Abbott B Abdallah J Abdelalim AA Abdesselam A Abdinov O Abi B Abolins M Abramowicz H Abreu H Acerbi E Acharya BS Adams DL Addy TN Adelman J Aderholz M Adomeit S Adragna P Adye T Aefsky S Aguilar-Saavedra JA Aharrouche M Ahlen SP Ahles F Ahmad A Ahsan M Aielli G Akdogan T Åkesson TP Akimoto G Akimov AV Akiyama A Alam MS Alam MA Albert J Albrand S Aleksa M Aleksandrov IN Alessandria F Alexa C Alexander G Alexandre G Alexopoulos T Alhroob M Aliev M Alimonti G Alison J Aliyev M Allport PP 《Physical review letters》2011,107(22):221802
A search for a heavy standard model Higgs boson decaying via H→ZZ→→?(+)?(-)νν, where ?=e, μ, is presented. It is based on proton-proton collision data at √s=7 TeV, collected by the ATLAS experiment at the LHC in the first half of 2011 and corresponding to an integrated luminosity of 1.04 fb(-1). The data are compared to the expected standard model backgrounds. The data and the background expectations are found to be in agreement and upper limits are placed on the Higgs boson production cross section over the entire mass window considered; in particular, the production of a standard model Higgs boson is excluded in the region 340相似文献
48.
49.
Abdallah Laradji 《Algebras and Representation Theory》2010,13(6):719-722
We show that if the direct product of countably many copies of a noetherian ring R is pure in a direct sum of finitely generated modules, then R satisfies the descending chain condition on two-sided ideals. This extends a recent result of Buchweitz and Flenner. 相似文献
50.
Abstract We study a perturbed anisotropic equation without using the knowledge of the limiting problem. This provides a different method
from that introduced by Brézis and Nirenberg [4]. Our arguments use some tools recently developed in [5, 6].
Keywords: Anisotropic critical exponent, Critical level, Compactness, Nehari manifold
Mathematics Subject Classification (2000): 35J25, 35J60, 35J65 相似文献