Showing papers by "United Arab Emirates University published in 1987"
TL;DR: In this article, the Schatten p-norm of operators on Hubert spaces has been shown to be tight for any three operators A, B, and X, for a Hubert space.
Abstract: We prove some inequalities for the Schatten p-norm of operators on a Hubert space. It is shown, among other things, that if A, B, and X are operators such that A + B ^ \X\ and A + B ^ \X* , then || AX + XB \\pp + || AX* + X*B \\pp for l^p
51 citations
TL;DR: Several transition metal complexes derived from 4,5-dimethyl-3-carboxaldehyde phenyl-thiosemicarbazone, LH, have been synthesized as mentioned in this paper.
21 citations
TL;DR: In this paper, a dioxouranium (VI) complex with the dibasic tridentate 7-carboxaldehyde-8-hydroxyquinoline-aroylhydrazone derivatives was synthesized and is bonded to the axial oxygen of the uranyl moiety and is easily substituted by dimethylsulphoxide.
Abstract: New dioxouranium(VI) complexes with the dibasic tridentate 7-carboxaldehyde-8-hydroxyquinoline-aroylhydrazone derivatives (1), have synthesized and is bonded to the axial oxygen of the uranyl moiety and is easily substituted by dimethylsulphoxide. The ligands contain intramolecular hydrogen bonds, one of which is from the enolic form of the hydrazone residue. The1H n.m.r. spectra show that the position of the hydrogenbonded proton of the hydrazone moiety is substituent dependent. The F(U−O) (mydn/A) and the bond length r(U−O) (A) of the UO bond are calculated from the i.r. data and related to the electronic properties of the substituents.
18 citations
TL;DR: In this article, the Hilbert-Schmidt norm of X ∈ C 2 is given by Ⅱ XⅡ 2 =( X, X ) ½, where X is any orthonormal basis of H and tr(.) is the natural trace on C 1.
Abstract: Let H denote a separable, infinite dimensional Hilbert space. Let B ( H ), C 2 and C 1 denote the algebra of all bounded linear operators acting on H , the Hilbert–Schmidt class and the trace class in B ( H ) respectively. It is well known that C 2 and C 1 each form a two-sided-ideal in B ( H ) and C 2 is itself a Hilbert space with the inner product where { e i } is any orthonormal basis of H and tr(.) is the natural trace on C 1 . The Hilbert–Schmidt norm of X ∈ C 2 is given by Ⅱ X Ⅱ 2 =( X, X ) ½ .
15 citations
TL;DR: In this article, the authors formulated the complexes of some γ-lactone derivatives with cobalt, nickel and copper as [ML 2 ]· n H 2 O, M = Co 2 +, Ni 2+ or Cu 2+, n = 2 or 3 and L = anion of corresponding ligand.
15 citations
TL;DR: In this article, a preheater and precalciner were investigated with respect to thermal energy consumption, losses and the potential of heat saving in a cement production line, and it was shown that 2% fuel saving can be achieved with highly viable payback times ranging from 0.07 to 0.72 yr.
Abstract: The cement industry is an energy intensive industry. Energy prices necessitate energy efficient systems, i.e. deep consideration of energy conservation and waste-heat recovery must be made. In the present work, a cement industry was examined with respect to thermal energy consumption, losses and the potential of heat saving. The production line investigated involved a cyclone preheater and precalciner prior to the kiln. In carrying out the work, data were obtained from the control room and by direct measurements on the different units. The thermal energy analysis of the system revealed that a considerable amount of fuel heat is dissipated. For recovering the waste heat, it has been proposed to insulate the external surface of the cyclones and ducts in the preheater unit. The optimization study on the insulations indicated that a 2% fuel saving can be achieved with highly viable payback times ranging from 0.07 to 0.72 yr.
11 citations
TL;DR: In this article, Moulis [1] gave a sufficient condition and a necessary condition on parameters m1 and m2 for the class Vm1,m2 to consist of univalent functions if S1 and S2 are taken to be convex univalent function in the unit disc.
Abstract: Let m1, m2 be any numbers and let Vm1,m2 be the class of functions of analytic in the unit disc E={z:|z|<1} for which f′(z)=(S′1(z))m1(S′2(z))m2 where S1 and S2 are analytic in E with S′1(0)=(S′2(0))=1. Moulis [1] gave a sufficient condition and a necessary condition on parameters m1 and m2 for the class Vm1,m2 to consist of univalent functions if S1 and S2 are taken to be convex univalent functions in E. In fact he proved that if f ϵ Vm1,m2 where S1 and S2 are convex and m1=k
10 citations
TL;DR: A series of transition metal complexes with phenyl-2-picolylketone-thiosemicarbazone, LH, of the general formula [ML2]ClnmH2O, (M=Cr3+, Mn2+, Fe2+, Rh3+, Ir3+ or Ru3+; n=0 or 1 and m=1,2 or 3) have been prepared and characterized as mentioned in this paper.
Abstract: A series of transition metal complexes with phenyl-2-picolylketone-thiosemicarbazone, LH, of the general formula [ML2]ClnmH2O, (M=Cr3+, Mn2+, Fe2+, Rh3+, Ir3+ or Ru3+; n=0 or 1 and m=1,2 or 3) have been prepared and characterized. Magnetic and spectral (electronic and vibrational) data are commensurate with an octahedral ligand field for all complexes. The variable temperature magnetic moment shows that the iron(II) complex exists in a temperature-dependent high-spin⇌low-spin equilibrium. The far i.r. spectra show that the strength of the M−S bond follows the order: Mn2+
8 citations
TL;DR: In this article, petrographic and stable isotopic analyses of dolomite from the reefal facies of the Lower Cretaceous Shuaiba Formation of Abu Dhabi, indicates two types of Dolomites: host and baroque.
8 citations
TL;DR: Methode directe de calcul du rotor d'un compresseur centrifuge a rapport de compression eleve as discussed by the authors, a rapport of compression elevenve is used in this article.
Abstract: Methode directe de calcul du rotor d'un compresseur centrifuge a rapport de compression eleve
2 citations
TL;DR: In this article, the Bouguer gravity coverage in the offshore Safaga area of the Egyptian Red Sea shelf was investigated by vertical second derivative, analytic upward continuation and subsurface modeling methods to study the basement setup and to investigate probable relationships to the Red Sea rifting.
TL;DR: In this article, the effect of operational-amplifier nonlinearity on the performance of active-R, active-C, and partial-active-R filters is investigated, and it is shown that the amplifier slew-rate limitation results in a characteristic which slants from the ideal flat response of the filter transfer functions.
Abstract: The effect of operational-amplifier nonlinearity on the performance of active-R, active-C, and “partial” active-R filters is investigated. Theoritical and experimental results show that the amplifier slew-rate limitation results in a characteristic which slants from the ideal flat response of the filter transfer functions.
TL;DR: In this article, the identification of a quadratic nonlinear system is concerned with the estimation of the lag (delay) relationship of the input process, the lead lag (time delay), and the unknown parameters.
Abstract: This paper is concerned with the identification of a quadratic non-linear system. The identification includes the estimation of the lag (delay) relationship of the input process, the lead lag (time delay) of the input/output system and the unknown parameters. The estimation procedures are based on the second-order covariances, cross-covariances and spectral densities. The estimation methods described here are illustrated with numerical examples.