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991.
Imran Ahmed 《Czechoslovak Mathematical Journal》2010,60(1):125-131
We recall first Mather’s Lemma providing effective necessary and sufficient conditions for a connected submanifold to be contained
in an orbit. We show that two homogeneous polynomials having isomorphic Milnor algebras are right-equivalent. 相似文献
992.
Chadi Hassan Taher 《manuscripta mathematica》2010,132(1-2):169-198
We calculate the parabolic Chern character of a bundle with locally abelian parabolic structure on a smooth strict normal crossings divisor, using the definition in terms of Deligne–Mumford stacks. We obtain explicit formulas for ch 1, ch 2 and ch 3, and verify that these correspond to the formulas given by Borne for ch 1 and Mochizuki for ch 2. 相似文献
993.
AbstractIn this article, we investigate the representation rings (or Green rings) of the Drinfeld doubles of the Taft algebras. It is shown that these Green rings are commutative rings generated by infinitely many elements subject to certain relations. The generators together with the subjecting relations are given. The stable Green rings of of the Drinfeld doubles of the Taft algebras are also described. 相似文献
994.
Nabil M. Hassan Tetsuo Ishikawa Masahiro Hosoda Atsuyuki Sorimachi Shinji Tokonami Masahiro Fukushi Sarata K. Sahoo 《Journal of Radioanalytical and Nuclear Chemistry》2010,283(1):15-21
The specific activities of 238U, 232Th, and 40K in selected building materials used in Japan were measured using a high-purity germanium detector. The uranium and thorium concentrations were determined from same samples using inductively coupled plasma mass spectrometry. There was a good agreement between the measurement of uranium and thorium with both methods (R 2 = 0.94, and 0.97, respectively). Based on the specific activities, we have estimated some hazard indexes such as radium equivalent activities (Ra eq), external hazard index (H ex), internal hazard index (H in), annual gonadal equivalent dose (AGED), internal alpha dose, mass exhalation rate and emanation coefficient of radon. 相似文献
995.
Fahmi Fariq Muhammad Ali Imran Abdul Hapip Khaulah Sulaiman 《Journal of organometallic chemistry》2010,695(23):2526-2531
For the purpose of investigating electro-molecular absorption bands, energy gaps, Eg and molecular energy levels (ionization potential, IP and electron affinity, EA) of tris (8-hydroxyquinolinate) gallium and aluminum, spectral analysis in conjunction with electrochemical measurements was carried out. UV-Vis-NIR and FTIR spectroscopic measurements were used to assign the electronic and molecular absorption bands in both of the materials. The XRD and scanning electronic microscopy (SEM) technique showed the amorphous nature. From the recorded data of cyclic voltammetry (CV) and materials absorption coefficient, HOMO, LUMO energy levels and energy gaps for Gaq3 and Alq3 were calculated. A bit smaller value of energy gap for Gaq3 (2.80 eV) compared to that of Alq3 (2.86 eV) has been ascribed to the differences in electronic configuration and coordinated bond lengths related to the central metal atom with respect to the quinolinate ligands. A higher value of HOMO energy level for the Alq3 (IP = 6.3 eV) revealed the need of higher potentials to oxidize its molecules comparing to that of Gaq3 (IP = 5.8 eV). It was observed that cationic metals have a direct effect on the physical and chemical behaviors of such organometallic materials that can be exploited to be used in tuning their properties to match the desired application in OSC and/or OLED technologies. 相似文献
996.
997.
Han SB Hassan A Kim IS Krische MJ 《Journal of the American Chemical Society》2010,132(44):15559-15561
A total synthesis of the oxo-polyene macrolide (+)-roxaticin is achieved in 20 steps from 1,3-propanediol. In this approach, 9 of 10 C-C bonds formed in the longest linear sequence are made via metal catalysis, including 7 C-C bonds formed by iridium catalyzed alcohol C-C coupling. Notably, the present synthesis, which represents the most concise preparation of any oxo-polyene macrolide reported to date, is achieved in the absence of chiral reagents and chiral auxiliaries with minimal use of premetalated C-nucleophiles. 相似文献
998.
A series of 5-unsubstituted and 5-substituted furfurylidenes have been prepared, under thermal and non-thermal microwave irradiation methods, via condensation of furfural and its derivatives with some of active methylene compounds. Furthermore, various condensate products from these furfurylidenes, which contain halogen or sulpher atoms, were also prepared. Structural elucidation of the synthesized compounds were determined on the basis of various spectroscopic methods. 相似文献
999.
Preparation, structure and spasmolytic activities of some derivatives of harmine series of alkaloids
Begum S Imran Hassan S Siddiqui BS Ifzal R Perwaiz S Kiran T Shaheen F Ghayur MN Gilani AH 《Natural product research》2006,20(3):213-227
Keeping in view the interesting chemistry and pharmacological importance of harmine series of bases -- the beta-carboline alkaloids, a number of new derivatives of tetrahydroharmine and harmalol have been prepared and characterized through spectral studies. Some of these derivatives showed spasmolytic activity. It was observed that all the N-acyl tetrahydroharmine derivatives are stable, not labile and no ring opening occurs in these compounds, as reported recently. 相似文献
1000.
Glaspell G Hassan HM Elzatahry A Fuoco L Radwan NR El-Shall MS 《The journal of physical chemistry. B》2006,110(43):21387-21393
Active gold and palladium nanoparticles supported on MgO nanocubes and ZnO nanobelts and transition-metal-containing MgO nanobelts were synthesized by combining evaporation and deposition-precipitation techniques. The high activity and stability of the Au/CeO2 and Pd/CeO2 nanoparticle catalysts deposited on the MgO cubes are remarkable and imply that a variety of efficient catalysts can be designed and tested using this approach. The significant increase in the concentration of corner and edge sites in MgO nanocubes make them well-defined supports to study the detailed mechanism of the catalytic activity enhancement. 相似文献