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991.
A general theory of collineation groups generated by quartic groups of even order is considered. Applications are given to collineation groups generated by ‘large’ quartic groups. © 2005 Wiley Periodicals, Inc. J Combin Designs 13: 195–210, 2005. 相似文献
992.
Mauro Marini 《Journal of Mathematical Analysis and Applications》2004,295(2):459-472
The problem of oscillation of a second order nonlinear difference system is considered and conditions for oscillation are derived by means of a complete analysis of nonoscillatory solutions. The case of systems with deviating arguments is also analyzed, and the results are shown to significantly generalize some existing ones. 相似文献
993.
Christopher B. Murray Stewart R. Korn Judith A.K. Howard 《Journal of fluorine chemistry》2005,126(4):569-574
A new nucleophilic fluorinating agent, derived from reaction of dimethylaminopyridine (DMAP) with pentafluoropyridine, has been synthesised and assessed in various carbon-fluorine bond forming processes. 相似文献
994.
D. Chowdhury M. Mlejnek Y. Mauro 《Journal of Optical and Fiber Communications Reports》2004,1(2):141-149
A procedure for evaluating system performance considering all orders of polarization mode dispersion (PMD) is
presented. The method provides engineering rules for computing system penalty
introduced by PMD. Computer simulation of PMD induced penalty indicates that
for generating a realistic system budget, effect of higher order PMD in
presence of chromatic dispersion is essential. Considering all of these
penalties, in order to obtain a system-reach of 3200 km at 40 Gb/s, a fiber
PMD of less than 0.04 ps/km1/2 is required when at the signal
wavelength chromatic dispersion is 0. In presence of 18 ps/nm chromatic
dispersion for the same system reach this PMD value reduces to about 0.02
ps/km1/2. 相似文献
995.
Chen Hu Shuping Liu Mauro Fasoli Anna Vedda Martin Nikl Xiqi Feng Yubai Pan 《固体物理学:研究快报》2015,9(4):245-249
Electron traps are known to a have great influence on the carriers transport process in Ce based scintillators. On the other hand, the role of hole traps in the scintillation process has been less considered. By means of electron spin resonance (ESR), we detected hole traps in highly Ce‐doped LuAG:Ce,Mg ceramics in the form of σ‐type O– centers. The g ‐tensor components turn out to be g⊥ = 2.0103, and g|| = 2.0023, revealing the axial symmetry of these defects. Mg‐perturbed variants of O– centers are proposed to exist in LuAG:Ce,Mg. Their occurrence is related to an elongated Mg–O bond as evidenced by DFT calculations. Finally, the multiple role of O– centers in the scintillation process is discussed.
996.
Cristiana da Silva Dênis A. M. da Silva Fillipe V. Rocha Carolina V. Barra Regina C. G. Frem Adelino V. G. Netto Antonio E. Mauro Eduardo T. de Almeida 《Journal of Thermal Analysis and Calorimetry》2014,117(3):1327-1334
The mononuclear pyrazolyl complexes [PdCl2(HIPz)2] (1), [PdBr2(HIPz)2] (2), [PdI2(HIPz)2] (3), [Pd(SCN)2(HIPz)2] (4), and [Pd(NHCOIPz)2] (5) have been prepared. Compound 1 was obtained from the displacement of acetonitrile from [PdCl2(CH3CN)2] precursor by the 4-iodopyrazole (HIPz) ligand, whereas 2–5 were synthesized by substitution of the chlorido in 1 by the respective anionic group. The compounds were characterized by elemental analysis, infrared spectroscopy, and 1H NMR spectroscopy. The thermal behavior of 1–5 has been studied by TG and DTA. The thermal stability of [PdX2(HIPz)2] compounds varies according to the trends X = Cl? < I? ? SCN?< Br?. No stable intermediates were isolated during the thermal decompositions due to the overlap of the degradation processes. The final products of the thermal decompositions were characterized as metallic palladium by X-ray powder diffraction. 相似文献
997.
Amphoteric,Prevailingly Cationic L‐Arginine Polymers of Poly(amidoamino acid) Structure: Synthesis,Acid/Base Properties and Preliminary Cytocompatibility and Cell‐Permeating Characterizations 下载免费PDF全文
998.
João Vitor de Assis Mara Rubia C. Couri Ricardo Silva Porto Wagner B. de Almeida Leonardo H. R. dos Santos Renata Diniz Mauro V. de Almeida 《Journal of heterocyclic chemistry》2013,50(Z1):E142-E147
This work describes the synthesis of inositol derivatives condensed with 2‐mercaptobenzothiazole or 2‐mercaptobenzimidazole, potential antimicrobial agents. These compounds were prepared by ring opening of epoxide intermediate (2S,3R‐epoxy‐1‐O‐methyl‐ l ‐chiro‐inositol and 2R,3S‐epoxy‐1‐O‐methyl‐ l ‐chiro‐inositol), which were obtained from l ‐quebrachitol (1‐O‐methyl‐chiro‐inositol). Microwave irradiation was used to promote the condensation reaction. 相似文献
999.
Mauro Cinquini 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):39-72
Abstract Highly stereoselective C[sbnd]C bond forming reactions can be performed with a variety of optically active sulfinyl derivatives to afford, after desulfurization, optically active sulfur-free products. 相似文献
1000.
Dr. Fabio Carniato Dr. Lorenzo Tei Dr. Aldo Arrais Prof. Leonardo Marchese Prof. Mauro Botta 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(4):1421-1428
The optimization of the physico‐chemical properties of both GdIII chelates and nanocarriers is of great importance for the development of effective nanosystems for magnetic resonance imaging (MRI) applications. With this aim, macrocyclic GdIII chelates were selectively attached to the pendant amino groups exposed to the external surface of spheroidal mesoporous silica nanoparticles (MSNs). This was achieved by treating the metal complexes with MSNs that contained the templating surfactant molecules confined within the silica channels (hexadecyltrimethylammonium (CTA)/MSN), followed by extraction of the surfactant. The nanoparticles showed greatly improved 1H relaxometric efficiency relative to corresponding systems that also feature GdIII chelates conjugated inside the pores. A further significant relaxivity enhancement was observed after chemical transformation of the free amino groups into amides. The ionic relaxivity of the final nanoparticles (r1p=79.1 mM ?1 s?1; 0.5 T, 310 K) is one of the highest reported so far. 相似文献