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111.
We extend the notion of a uniform space in a natural way by defining a uniform spaces in L-fuzzy spaces.Although these spaces seem quite similar to ordinary case,we show that the category of this uniform spaces is a good extension of the category of ordinary uniform spaces and the category of L-uniform spaces.Moreover,we introduce the concept of uniform topological spaces in the framework of uniform spaces in L-fuzzy spaces.Furthermore,the relation between proximity and uniform spaces in L-fuzzy spaces will... 相似文献
112.
Kamel Hooman Alireza Pourshaghaghy Arash Ejlali 《应用数学和力学(英文版)》2006,27(5):617-626
The viscous dissipation effect on forced convection in a porous saturated circular tube with an isoflux wall is investigated on the basis of the Brinkman flow model. For the thermally developing region, a numerical study is reported while a perturbation analysis is presented to find expressions for the temperature profile and the Nusselt number for the fully developed region. The fully developed Nusselt number found by numerical solution for the developing region is compared with that of asymptotic analysis and a good degree of agreement is observed. 相似文献
113.
Wanas AS Matsunami K Otsuka H Desoukey SY Fouad MA Kamel MS 《Chemical & pharmaceutical bulletin》2010,58(12):1596-1601
From the EtOAc and 1-BuOH fractions, three new ursane-type and four new lupane-type triterpenes, along with nine known glycosides and glycosyl esters of lupane-type were isolated from the leaves of Schefflera actinophylla. All the isolated compounds were obtained for the first time from this plant. The structures of the new triterpenes were determined through a combination of spectroscopic and chemical analyses. 相似文献
114.
In this article, we introduce the two dimensional Mellin transform M_(f)(s, t),give some properties, establish the Paley-Wiener theorem and Plancherel formula, present the Hausdorff-Young inequality, and find several applications for the two dimensional Mellin transform. 相似文献
115.
116.
117.
Kenneth Berg David Gove Kamel Haddad 《Proceedings of the American Mathematical Society》1998,126(3):899-905
Enveloping semigroups of topological actions of semigroups on compact spaces are studied. For zero dimensional spaces, and under modest conditions on , the enveloping semigroup is shown to be the Stone-\v{C}ech compactification if and only if some Cartesian product has the two-shift as a factor. Examples are discussed showing that, unlike in the measure theory case, positive entropy does not imply the existence of such a factor even if the Cartesian product has large entropy.
118.
Ali Ourari Kamel Ouari Wahiba Moumeni Lakhdar Sibous Gilles M. Bouet Mustayeen A. Khan 《Transition Metal Chemistry》2006,31(2):169-175
Salicylaldehyde or 5-bromosalicylaldehyde reacted with 2,3-diaminophenol in absolute EtOH in a 2:1 molar ratio to give new
unsymmetrical Schiff bases (H2L). The bases were used as ligands to coordinate Mn(III), Ni(II) and Cu(II) chlorides leading to [MnIIIClL] · EtOH and [MIIL] or [MIIL] · 2H2O (M = Ni or Cu) complexes. Their structures were determined using mass spectroscopy, IR, u.v.–vis and 1H-n.m.r. The cyclic voltammetry in acetonitrile showed irreversible waves for both ligands. Under the same experimental conditions,
the complexes exhibited mainly the non-reversible reduction of the Ni(II) or Cu(II) ion to Ni(0) or Cu(0), while the reduction
of Mn(III) to Mn(II) was found to be a quite reversible phenomenon. 相似文献
119.
Sueo Machi Ihab Kamel Joseph Silverman 《Journal of polymer science. Part A, Polymer chemistry》1970,8(11):3329-3337
The radiation-induced grafting of low-density polyethylene in contact with styrene solution was studied. The effect of the degree of swelling of the polymer on the rate of grafting was investigated by diluting the styrene with methanol and with n-octane. For styrene-methanol solution, the rate of grafting was found to increase with degree of swelling, passing through a maximum when the sorbed solvent reaches 6.2 wt-% (70 vol-% methanol in the outside solution) and decreasing therafter. The methanol fraction of the sorbed liquid is far too small to cause precipitation of the grafted chains and inhibition of their termination rate. The dilution of styrene by octane has no effect on the swelling of polyethylene, but it decreases the grafting rate over the entire concentration range. The results are explained in terms of the concentration of sorbed monomer and the viscosity of the amorphous region of the polyethylene swollen by nonpolar liquids. Supporting evidence for the mechanism is presented in the form of grafting kinetic data as a function of dose rate (2.8 × 102?9.5 × 104 rad/hr), and post-irradiation grafting measurements for polyethylene in methanol-styrene (70/30, v/v). The data indicate that at the maximum grafting rate an optimum is achieved between a high concentration of sorbed monomer and a low viscosity for the poorly swelled polymer matrix. 相似文献
120.
M. R. Mahmoud M. A. Hamed M. S. Kamel S. A. El-Gyar 《Monatshefte für Chemie / Chemical Monthly》1985,116(11):1291-1304
Arylidene-anthranilic acidSchiff base complexes with Th(IV), UO2(II), La(III), Ce(III), and Zr(IV) have been isolated and studied by several techniques, e.g. elemental analysis, electronic and IR spectra and conductance measurements. It is concluded that the salicylideneanthranilic acidL
3 is coordinated to the metal ion as bivalent tridentate ONO ligand (L
–2) while the other ligands behave as monovalent bidentate ON ligands. Furthermore, the molecular structure effect of these compounds on their tendency towards complex formation was investigated and discussed. The possibility that the Cu(II) complex ofL
3 can act as bidentate ligand, coordinating through itscis-oxygen atoms to form binuclear metal complexes was studied.
Ein- und zweikernige Metall-Komplexe von Aryliden-Anthranilsäure-Schiff-Basen
Zusammenfassung Es wurden Aryliden-Anthranilsäure-Schiff-Basen mit Th(IV), UO2(II), La(III), Ce(III) und Zr(IV) isoliert und mittels Elementaranalysen, Elektronen-und IR-Spektroskopie und Leitfähigkeitsmessungen untersucht. Es wird aus den Untersuchungen geschlossen, daß Salicylidenanthranilsäure (L 3) als bivalenter dreizähniger ONO-Ligand (L –2) an das Metallion koordiniert, währenddessen die anderen Liganden als monovalente zweizähnige Liganden agieren. Außerdem wurden Struktureffekte dieser Verbindungen in bezug auf ihre Komplexbildungstendenz untersucht. Die Möglichkeit, daß der Cu(II)-Komplex vonL 3 über die Koordination mit dencis-Sauerstoff-Atomen und unter Bildung eines zweikernigen Metallkomplexes als zweizähniger Ligand agieren kann, wurde untersucht.相似文献