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81.
82.
Let a finite dimensional algebra R be a split extension of an algebra A by a nilpotent bimodule Q. We give necessary and sufficient conditions for a (partial) tilting module TA to be such that T?A RR is a (partial) tilting module. If this is not the case, but QA is generated by the tilting module TA , then there exists a quotient [Rbar] of R such that T?A [Rbar][Rbar] is a tilting module. 相似文献
83.
84.
ABSTRACT In this communication we describe the synthesis of epoxidized castor oil (ECO) as an interesting and inexpensive biorenewable monomer by an efficient and low cost epoxidation process. Also described are studies of the photoinitiated cationic polymerization of ECO using diaryliodonium salt photoinitiators. The influence of the structure and the concentration of the photoinitiator on the polymerization are reported. The ability of photosensitizers to accelerate the photopolymerization was also studied. Studies comparing the photopolymerization behavior of ECO with other commercially available epoxidized linseed and soybean oils and with other types of synthetic epoxy monomers were conducted. The excellent reactivity of ECO can be ascribed to the presence of both epoxy and hydroxyl groups in the molecule which permits this material to polymerize mainly by an activated monomer mechanism. 相似文献
85.
86.
A new dual‐functional Cu(II) complex and its nanohybrid form encapsulated into NaY zeolite cavities were synthesized. The synthesized compounds were characterized using elemental analyses, X‐ray fluorescence, infrared, 1H NMR, electronic, electron spin resonance and mass spectra, powder X‐ray diffraction, surface area and transmission electron microscopy in addition to conductivity and magnetic susceptibility measurements. The encapsulated Cu(II) complex was catalytically tested for degradation of industrial wastewater. The decolorization and mineralization results indicate that the Cu(II) complex encapsulated into zeolite host is an effective heterogeneous catalyst for real industrial wastewater remediation. In addition, both free and encapsulated Cu(II) complexes were tested as anti‐microbial and anti‐tumour agents. The results show that the Cu(II) complex encapsulated into zeolite has a high activity (IC50 = 14.4 μg ml?1). The results of in vivo toxicity experiments indicate that the Cu(II) complex encapsulated into zeolite is a less toxic biocompatible material (LD50 = 1245 mg kg?1). The catalytic properties, cytotoxicity and toxicity of the new nanohybrid Cu(II) complex encapsulated into zeolite make it a promising eco‐friendly and biocompatible material for water remediation and biomedical applications. 相似文献
87.
Ring transformation of 6‐bromochromone‐3‐carbonitrile ( 1 ) with malononitrile dimer in basic medium furnished the unexpected (9‐bromo‐3‐cyano‐5‐oxo‐1,5‐dihydro‐2H‐chromeno[4,3‐b]pyridin‐2‐ylidene)propanedinitrile ( 2 , BCOCPP ). Density functional theory, theoretical investigation of the electronic structure, geometries linear polarizability ?Δα? (Quadrupole moment), first‐order hyperpolarizability ?β? (Octapole moment), natural bonding orbital, molecular electrostatic potential contours, thermo‐chemical parameters, harmonic vibration frequencies, the FT‐IR spectrum of the compound ( 2 , BCOCPP ) in the solid phase was recorded, and time‐dependent density functional theory calculations at the B3LYP/6‐311G (d,p) level of theory, UV‐Vis spectra, in both ethanol and dioxane solvents have been employed for compound ( 2 , BCOCPP ). The geometrical and energetic parameters have been extensively investigated to reveal the reason behind the selective formation of compound ( 2 , BCOCPP ), instead of expected product 3 . The Coulomb‐attenuating method‐B3LYP and Corrected Linear Response Polarizable Continuum Model studied for theoretically obtaining the electronic absorption spectra in gas phase, ethanol, and dioxane, respectively, and indicate a good agreement with the observed spectra. The heterojunction based on BCOCPP showed phototransient properties under various illumination intensities that give the recommendation of the studied heterojunction in the field of optoelectronic device application. 相似文献
88.
Reda M. Abdel‐Rahman Mohamed S. T. Makki Tarik E. Ali Magdy A. Ibrahim 《Journal of heterocyclic chemistry》2015,52(6):1595-1607
The synthesis and chemical behavior of 3‐functionalized 5,6‐diphenyl‐1,2,4‐triazines towards some electrophilic and nucleophilic reagents are reviewed. The synthesis, unique features, and medicinal, pharmacological, and biological significance of these constituents are also reported. 相似文献
89.
In this paper, we study the covering theory of laura algebras. We prove that if a connected laura algebra is standard (that is, has a standard connecting component), then it has Galois coverings associated to the coverings of the connecting component. As a consequence, the first Hochschild cohomology group of a standard laura algebra vanishes if and only if it has no proper Galois coverings. 相似文献
90.
K.B. Haley† 《International Journal of Mathematical Education in Science & Technology》2013,44(4):343-347
The paper reviews the history of education in operational research and indicates the needs both of a practitioner and of a manager. It describes how these can be met by standard course teaching and suggests some areas of development. 相似文献