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191.
Mauricio Bellini 《General Relativity and Gravitation》2002,34(9):1483-1489
I study a thermodynamical approach to scalar metric perturbations during the inflationary stage. In the power-law expanding universe here studied, I find a negative heat capacity as a manifestation of superexponential growing for the number of states in super Hubble scales. The power spectrum depends on the Gibbons-Hawking and Hagedorn temperatures. 相似文献
192.
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194.
One-step biomimetic conversion of a furanoheliangolide into an eremantholide using Stryker’s reagent
Daiane Cristina Sass Vladimir Constantino Gomes Heleno Joo Luis Callegari Lopes Mauricio Gomes Constantino 《Tetrahedron letters》2008,49(24):3877-3880
The conversion of a furanoheliangolide structure (15-deoxygoyazensolide) into an eremantholide one (eremantholide C) was achieved by tandem hydride conjugate addition–intramolecular carbanion addition using Stryker’s reagent. 相似文献
195.
Carbajal-Tinoco MD 《The Journal of chemical physics》2008,128(18):184507
We present a new closure relation that is an extension of the thermodynamically consistent approximation of Rogers and Young [Phys. Rev. A 30, 999 (1984)]. In the proposed closure, we introduce a nonlinear term along with an additional thermodynamic consistency equation. We compare some thermodynamic and structural properties obtained within our scheme with the corresponding results emerging from other approaches that include numerical simulations and other closure approximations. For the systems considered here, the results derived from our scheme are in better agreement with the reference values of the simulations. 相似文献
196.
Fast detection of Piscirickettsia salmonis in Salmo salar serum through MALDI‐TOF‐MS profiling
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Verónica R. Olate Fabiane M. Nachtigall Leonardo S. Santos Alex Soto Macarena Araya Sandra Oyanedel Verónica Díaz Vanessa Marchant Mauricio Rios‐Momberg 《Journal of mass spectrometry : JMS》2016,51(3):200-206
Piscirickettsia salmonis is a pathogenic bacteria known as the aetiological agent of the salmonid rickettsial syndrome and causes a high mortality in farmed salmonid fishes. Detection of P. salmonis in farmed fishes is based mainly on molecular biology and immunohistochemistry techniques. These techniques are in most of the cases expensive and time consuming. In the search of new alternatives to detect the presence of P. salmonis in salmonid fishes, this work proposed the use of MALDI‐TOF‐MS to compare serum protein profiles from Salmo salar fish, including experimentally infected and non‐infected fishes using principal component analysis (PCA). Samples were obtained from a controlled bioassay where S. salar was challenged with P. salmonis in a cohabitation model and classified according to the presence or absence of the bacteria by real time PCR analysis. MALDI spectra of the fish serum samples showed differences in its serum protein composition. These differences were corroborated with PCA analysis. The results demonstrated that the use of both MALDI‐TOF‐MS and PCA represents a useful tool to discriminate the fish status through the analysis of salmonid serum samples. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
197.
Fast analysis of soy isoflavones by high-performance liquid chromatography with monolithic columns 总被引:1,自引:0,他引:1
A fast method using high-performance liquid chromatography based on two monolithic columns has been developed for the simultaneous determination of isoflavones extracted from soybeans and derived foods. The 12 main isoflavones were resolved in 10 min in two coupled monolithic columns working at 35 °C using a elution gradient of acidified water (0.1% acetic acid) and methanol (0.1% acetic acid) at a flow rate of 5 mL min−1. Retention time and relative area standard deviations were below 1% for all isoflavones. The method developed was successfully applied to several soy food samples and spiked samples. Total isoflavone concentration in sampled soy foods ranged from 34.28 mg L−1 to 4.29 mg g−1. 相似文献
198.
Dantelle G Mortier M Monteil A Chaussedent S Silva MA 《The Journal of chemical physics》2007,127(9):094509
Molecular dynamics simulations of the devitrification process of a lead fluoride glass doped with Er(3+) ions were carried out. This technique appears to be a relevant way to perform systematic analysis of the system structure and to study the influence of defects on PbF2 crystallization. We modeled the total enthalpy, the radial distribution functions, and the diffracted intensities of systems containing different amounts of Er(3+) ions. We demonstrated by means of different simulations that Er(3+) ions lowered the devitrification temperature of PbF2, in good agreement with the experimental results. The genuine role of Er(3+) ions in the devitrification process of PbF2 has been investigated. Er(3+) ions have an unquestionable influence of the crystallization of PbF2. Although the latter does not start in the nearest neighborhood of Er(3+) ions, the presence of Er(3+) ions in a close environment may favor the lead fluoride crystallization. 相似文献
199.
Total ion yield spectra and photoinduced fragmentations following S 2p, Cl 2p, and O 1s inner shell excitations of methoxycarbonylsulfenyl chloride, CH(3)OC(O)SCl, have been studied in the gaseous phase by using synchrotron radiation and multicoincidence techniques, which include photoelectron-photoion coincidence (PEPICO) and photoelectron-photoion-photoion coincidence (PEPIPICO) time-of-flight (TOF) mass spectrometry. According to the analysis of the partial ion yield spectra the S+ ion signal shows a steep enhancement near the S 2p resonance, which could represent an evidence of state-specific fragmentations promoted by electronic excitations from the S 2p to vacant orbitals with strong antibonding character mainly located at the sulfur atom. The dissociation dynamics for selected PEPIPICO islands have been discussed. Fragmentation channels that involve the extrusion of H+ and CH(x)+ (x = 0, 1, 2, 3) fragments have been predominantly observed for dissociation of doubly charged CH(3)OC(O)SCl(2+). 相似文献
200.
Alejandro Hernández-Tello José Arrazola Ramírez Mauricio Osorio Galindo 《Logica Universalis》2017,11(4):507-524
The authors of Beziau and Franceschetto (New directions in paraconsistent logic, vol 152, Springer, New Delhi, 2015) work with logics that have the property of not satisfying any of the formulations of the principle of non contradiction, Béziau and Franceschetto also analyze, among the three-valued logics, which of these logics satisfy this property. They prove that there exist only four of such logics, but only two of them are worthwhile to study. The language of these logics does not consider implication as a connective. However, the enrichment of a language with an implication connective leads us to more interesting systems, therefore we look for one implication for these logics and we study further properties that the logics obtain when this connective is added to these systems. 相似文献