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51.
1 INTRODUCTIONWith the invention of lasers[1] and the observation of second-harmonic generation in quartz[2], nonlinear optics(NLO), as a cornerstone of photonics, has been booming since 1960's. And intense interest has been aroused to search materials exhibiting appropriate nonlinear optical properties suitable for the construction of practical optical devices for the important techniques such as frequency converting, signal processing and optical computing[3~6]. In order to determine … 相似文献
52.
SABen-Hao CAIXu TAIAn ZHOUDai-Mei 《理论物理通讯》2004,42(3):403-406
We present the simulation results of the net charge fluctuation in Au Au collisions at √Snn=130 GeV from a dynamic model, JPCIAE, and its revisions. The simulations are done for the quark-gluon matter, the directly produced pions, the pion matter, and the hadron matter. The simulated net charge fluctuation of the quark-gluon matter is close to the thermal model prediction for the quark-gluon gas. However, the discrepancy exists comparing the simulated net charge fluctuation for directly produced pions and the pion matter with the thermal model prediction for pion gas and the resonance pion gas, respectively. The net charge fluctuation of hadron matter from default JPCIAE simulations is nearly 3.5 times larger than quark-gluon matter. A discussion is given for the net charge fluctuation as an evidence of QGP phase transition. 相似文献
53.
G. M. Corrêa L. P. Bellé L. Bajerski S. H. M. Borgmann S. G. Cardoso 《Chromatographia》2007,65(9-10):591-594
A reversed-phase high-performance liquid chromatographic method has been developed and validated for quantitative determination of deflazacort in tablets and in compounded capsules. Isocratic chromatography was performed on a C18 column with acetonitrile–water 80:20 (v/v) as mobile phase at a flow rate of 1.0 mL min?1. UV detection was at 240 nm. The linearity of the method was good (r > 0.999), as also were intra-day and inter-day precision (RSD <2%) and accuracy (recovery >98%). The method was also validated for specificity and robustness. The results showed the proposed method is suitable for its intended use. 相似文献
54.
P. MORLIÉRE M. BAZIN L. DUBERTRET R. SANTUS T. SA E. MELO G. HÜPPE J. HAIGLE P. FORLOT A. BERNARD 《Photochemistry and photobiology》1991,53(1):13-19
5-Geranoxypsoralen, commonly called bergamottin, a major furocoumarin contained in bergamot oil, is reported in vitro as a highly photoreactive psoralen. In ethanol, it exhibits quite a high triplet state quantum yield (approximately 0.37). The triplet state is involved in subsequent photochemistry which depends on the initial concentration and on the presence of oxygen. In contrast to most psoralens, absorption and fluorescence data suggest that 5-geranoxypsoralen does not interact with DNA in the dark. No UVA-induced interstrand cross-links in DNA were shown. 相似文献
55.
Interfacial properties and thermal stability of modified poly(m‐phenylene isophthalamide) thin films
Sandra Cruz dos Santos Lara Fernandes Loguercio Diogo Silva Corrêa Michael Ramos Nunes Marcos Antônio Villetti Irene Teresinha Santos Garcia 《Surface and interface analysis : SIA》2013,45(4):837-843
Poly(m‐phenylene isophthalamide) (PMIA) is a resistant to high temperatures and chemically stable engineering material. The application as coatings and membranes, however, is limited by its poor interaction with other materials. In this report, we describe the molecular modification of PMIA through reaction with dimsyl sodium and 2‐iodine‐1‐ethanol. The substitution of 58% of amide hydrogen by ethanol (etOH) groups produces a material (MPMIA) able to develop regularly structured films on silicon substrate. The morphology of the films is dependent on the ionic strength of the precursory solution. MPMIA starts a degradation process by losing the etOH group. MPMIA has a better affinity with poly(p‐cresolformaldehyde) than with a pristine one, increasing the range of composition in which thermal stability and miscibility are observed. Thin films of these blends have different morphologies that vary from nanometric porous to two‐phase microstructured grains, according to the composition. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
56.
In earlier papers it has been shown that certain different types of conditions on the factors in a factorization of a finite abelian group by its subsets lead to the conclusion that one factor must be a subgroup. In this paper the common generalization is proved that this result still holds even if different factors satisfy different types of condition. It is also shown that one condition may be weakened without effecting the conclusion. 相似文献
57.
L. Corrêa G.A. B. Lima M.A. C. Candezano M.P. S. Braun C.M. Oishi H.A. Navarro V.G. Ferreira 《国际流体数值方法杂志》2013,72(12):1263-1285
A bounded upwinding scheme for numerical solution of hyperbolic conservation laws and Navier–Stokes equations is presented. The scheme is based on convection boundedness criterion and total variation diminishing stability criteria and developed by employing continuously differentiable functions. The accuracy of the scheme is verified by assessing the error and observed convergence rate on 1‐D benchmark test cases. A comparative study between the new scheme and conventional total variation diminishing/convection boundedness criterion‐based upwind schemes to solve standard nonlinear hyperbolic conservation laws is also accomplished. The scheme is then examined in the simulation of Newtonian and non‐Newtonian fluid flows of increasing complexity; a satisfactory agreement has been observed in terms of the overall behavior. Finally, the scheme is used to study the hydrodynamics of a gas‐solid flow in a bubbling fluidized bed. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
58.
Luiz Carlos Machado Marcos Tadeu D’Orlando de Azeredo Hamilton Perez Soares Corrêa Jivaldo do Rosário Matos Ítalo Odone Mazali 《Journal of Thermal Analysis and Calorimetry》2012,107(1):305-311
This study investigates two lanthanide compounds (La3+ and Sm3+) obtained in water/ethyl alcohol solutions employing the anionic surfactant diphenyl-4-amine sulfonate (DAS) as ligand. Both
sulfonates were characterized through IR, TG/DTG (O2 and N2). The thermal treatment of both compounds at 1273 K under air leaves residues containing variable percentages of lanthanide
oxysulfide/oxysulfate phases shown by synchrotron high-resolution XRD pattern including the Rietveld analysis. The phase distributions
found in the residues evidence the differences in the relative stability of the precursors. 相似文献
59.
On a ‐Kirchhoff equation with critical exponent and an additional nonlocal term via truncation argument
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Francisco Julio S. A. Corrêa Augusto César dos Reis Costa 《Mathematische Nachrichten》2015,288(11-12):1226-1240
We study existence and multiplicity of solutions of the following nonlocal ‐Kirchhoff equation with critical exponent, via truncation argument on the Sobolev space with variable exponent, where Ω is a bounded smooth domain of , , M, f are continuous functions, , and are real parameter. 相似文献
60.
Cátia Crispilho Corrêa Lucimara Aparecida Forato Luiz Alberto Colnago 《Analytical and bioanalytical chemistry》2009,393(4):1357-1360
High intake of saturated fat from meats has been associated with cardiovascular disease, cancer, diabetes, and others diseases.
In this paper, we are introducing a simple, high-throughput, and non-destructive low-resolution nuclear magnetic resonance
method that has the potential to analyze the intramuscular fat content (IMF) in more than 1,000 beef portions per hour. The
results can be used in nutritional fact labels, replacing the currently used average value. The method is based on longitudinal
(T
1) and transverse (T
2) relaxation time information obtained by a continuous wave-free precession (CWFP) sequence. CWFP yields a higher correlation
coefficient (r = 0.9) than the conventional Carr-Purcell-Meiboom-Gill (CPMG) method (r = −0.25) for IMF in beef and is just as fast and a simpler pulse sequence than CPMG. The method can also be applied to other
meat products. 相似文献