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排序方式: 共有402条查询结果,搜索用时 31 毫秒
91.
92.
93.
Fethi Mahmoudi 《Advances in Mathematics》2007,209(2):460-525
We consider the equation −ε2Δu+u=up in Ω⊆RN, where Ω is open, smooth and bounded, and we prove concentration of solutions along k-dimensional minimal submanifolds of ∂Ω, for N?3 and for k∈{1,…,N−2}. We impose Neumann boundary conditions, assuming 1<p<(N−k+2)/(N−k−2) and ε→0+. This result settles in full generality a phenomenon previously considered only in the particular case N=3 and k=1. 相似文献
94.
Catalin Florin Petre Abdelaaziz Azizi Caroline Olsen Abdelaziz Baçaoui Faïçal Larachi 《Journal of separation science》2008,31(22):3902-3910
A capillary electrophoretic protocol for the separation and quantification of the most important species potentially liberated during the cyanidation of gold sulfide‐rich ores was accomplished in this study. The separation of 11 ions: S2O32–, Cu(CN)32–, Fe(CN)64–, Fe(CN)63–, SCN–, Au(CN)2–, Ag(CN)2–, SO42–, OCN–, SO32–, and HS– was achieved using an indirect UV detection method. The robustness of the analytical protocol was tested by analyzing ions speciation during the cyanidation of two gold sulfide‐rich ores. The 1‐h cyanidation of the two ores released up to six complexes into solution: S2O32–, Cu(CN)32–, SCN–, Fe(CN)64–, OCN–, and SO42–. The mineralogy of the ore was found to influence directly the nature and the amount of the dissolved species. Conserving the cyanidation solution for 72 h after sampling resulted in 96% total sulfur recovery. These results allow us to conclude that the analytical protocol developed in this study can become very useful for the optimization of precious‐metals cyanidation plants. 相似文献
95.
W. F. Mahmoudi N. Ben Nessib S. Sahal-Bréchot 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2008,47(1):7-10
Owing to the increasing sensitivity of detectors,
accurate line profiles are needed for accurate stellar
atmospheres modelling and for laboratory and technological plasmas
as well. So, Stark broadening parameters of isolated lines of
complex atoms and ions within the impact and quasistatic
approximation are needed, even if the atomic abundance of the considered element is low.
Angular factors of the diagonal line strength entering the
quadrupole term appearing in the semi-classical expression of the
width of line broadened by electron or ion perturbers, are needed.
The aim of this paper is to extend the previous calculations of
this diagonal multiplet factor which were obtained for
configurations of the type ln and l1
nl2
m to
more complex configurations in LS coupling.
To study the Stark broadening of isolated lines in the impact and
quasistatic approximation, we use the semi-classical-perturbation
treatment, including both dipole and quadrupole contribution in
the expansion of the electrostatic interaction between the optical
electron and the perturber. We also use the Fano-Racah algebra.
Angular factors of the diagonal line strength entering the
quadrupole term appearing in the semi-classical expression of the
width of line broadened by electron or ion perturbers, are
calculated. New diagonal multiplet factor formulae for more
complicated configurations such as
(n1l1
n(LnSn)n2l2
m(LmSm)n3l3
p(LpSp))
are provided.
These formulae can enter the computer Stark semi-classical
perturbation codes. 相似文献
96.
Houmam A Hamed EM Hapiot P Motto JM Schwan AL 《Journal of the American Chemical Society》2003,125(42):12676-12677
The electrochemical reduction of benzyl thiocyanate and p-nitrobenzyl thiocyanate was investigated in acetonitrile at an inert electrode. These two compounds reveal a change in the reductive cleavage mechanism, and more interestingly, they show a clear-cut example of a regioselective bond dissociation. Both phenomena may be understood on the basis of the dissociative ET theory and its extension to the formation/dissociation reactions of radical ions. While the effect of the standard oxidation potential of the leaving group seems to be predominant in understanding the change in the ET mechanism by changing the driving force, the regioselective cleavage is dictated by changes in the intrinsic barrier related to the nature of the substituent on the aryl moiety. 相似文献
97.
98.
Majid Montazer Mahbubeh Dastjerdi Maryam Azdaloo Mahnaz Mahmoudi Rad 《Cellulose (London, England)》2015,22(6):4049-4064
99.
100.