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941.
Radioiodine adsorption from aqueous solutions on metal-containing membranes with different compositions have been investigated.
Radioiodine can be adsorbed from aqueous media using Bi- or Ag-containing membrane filters. The results of testing the metal-containing
membrane filters with NPP water coolant samples are presented. A procedure for the determination of radioiodine in the NPP
water coolant is developed. 相似文献
942.
943.
944.
A comparison between rate-equation and Fabry-Perot amplifier models of injection locked laser diodes
The rate-equation and the Fabry-Perot amplifier models for injection locked laser diodes are compared. Both models give identical results at the limiting case of no injected signal. The Fabry-Perot model predicts a wider locking bandwidth and is more useful for large signal applications. The rate-equation model is suitable for investigating the dynamic properties. Numerical results from both models are presented. 相似文献
945.
Ibrahim M. Labouta Ahmed M. M. Hassan Omaima M. Aboulwafa Ola Kader 《Monatshefte für Chemie / Chemical Monthly》1989,120(6-7):571-574
Summary The synthesis andin vitro antimicrobial evaluation of several benzimidazole derivatives with different heterocyclic nuclei at position-2 are described.
Synthese einiger substituierter Benzimidazole mit potentieller antimikrobieller Aktivität
Zusammenfassung Die Synthese und antimikrobielle Prüfung einiger Benzimidazole mit verschiedenen heterozyklischen Substituenten in 2-Stellung wird beschrieben.相似文献
946.
Rates of solvolysis of ions [Co(3Rpy)4Cl2]+ with R = Me and Et have been measured over a range of temperatures for a series of water-rich water + methanol mixtures to investigate the effect of changes in solvent structure on the solvolysis of complexes presenting a largely hydrophobic surface to the solvent. The variation of the enthalpies and entropies of activation with solvent composition has been determined. A free energy cycle relating the free energy of activation in water to that in water + methanol is applied using free energies of transfer of individual ionic species from water into water + methanol. Data for the free energy of transfer of chloride ions ΔG(Cl?) from both the spectrophotometric solvent sorting method and the TATB method for separating ΔG(salt) into ΔG(i) for individual ions are used: irrespective of the source of ΔG(Cl?), in general, ?ΔG(Co(Rpy)4Cl2+) > ?ΔG(Co(Rpy)4Cl2+), where Rpy = py, 4Mepy, 4Etpy, 3Etpy, and 3Mepy, showing that changes in solvent structure in water-rich water + methanol mixtures generally stabilize the cation in the transition state more than the cation in the initial state for this type of complex ion. A similar result is found when the free energy cycle is applied to the solvolysis of the dichloro (2,2′,2″-triaminotriethylamine)cobalt(III) ion. The introduction of a Me or Et group on the pyridine ring in [Co(Rpy)4Cl2]+ has little influence on the difference {ΔG(Co(Rpy)4Cl2+)?ΔG(Co(Rpy)4Cl2+)} in water + methanol with the mol fraction of methanol < 0.20. 相似文献
947.
948.
Sobhy El-Sayed Ibrahim 《Czechoslovak Mathematical Journal》2004,54(1):9-29
In this paper, the general ordinary quasi-differential expression M
pof n-th order with complex coefficients and its formal adjoint M
p
+
on any finite number of intervals I
p
=(a
p
,b
p
),p= 1,...,N, are considered in the setting of the direct sums of L
wp
2
(a
p
,b
p
)-spaces of functions defined on each of the separate intervals, and a number of results concerning the location of the point spectra and the regularity fields of general differential operators generated by such expressions are obtained. Some of these are extensions or generalizations of those in a symmetric case in [1], [14], [15], [16], [17] and of a general case with one interval in [2], [11], [12], whilst others are new. 相似文献
949.
950.
Ibrahim A. Salem 《国际化学动力学杂志》1995,27(5):499-505
The kinetics of the H2O2 decomposition in presence of Fe(III)- and Cr(III)-complexes of mono-, di-, and triethanolamine supported on Dowex-50W resin have been investigated. The decomposition process proceeded with first-order kinetics for the substrate concentration. The rate of reaction increased with increasing number of the coordinated ligands in the metal complex as well as with increasing ligand basicity. The decomposition reaction involved the formation of an intermediate active species, which converts into a peroxo-metal complex of brown, green, or gray color. A mechanism describing the decomposition process is proposed. © 1995 John Wiley & Sons, Inc. 相似文献