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41.
Kazuhiro Tsuji Michio Sorai Hiroshi Suga Syüzö Seki 《Molecular Crystals and Liquid Crystals》2013,570(3-4):305-317
Abstract The heat capacity of HBAF has been measured between 15 K and 385 K. Four phase transitions were found at 328.07 K (crystal-smectic B); 330.33 K (smectic B-smectic A); 334.88 K (smectic A-nematic); and 336.33 K (nematic-isotropic liquid), respectively. The enthalpies and entropies of these transitions were determined to be 23.22 kJ mol?1/70.7 JK?1 mol?1; 3.05/9.2; 3.41/10.2; and 1.17/3.5, respectively. The total transition entropy of HBAF agreed well with those previously reported for the present homologues. The standard thermodynamic functions were estimated up to 385 K. The heat capacity curve of HBAF in the transition region had a close resemblance to that of p-n-hexyloxybenzylideneamino-p'-chlorobenzene. The entropies of the smectic A-nematic and nematicisotropic liquid transitions were compared with those theoretically derived by McMillan. The smectic B-smectic A transition entropy was interpreted in terms of order-disorder phase transition associated with the orientation of molecule. 相似文献
42.
Le Thiem Ngoc Hoang Sy Minh Tuan Nguyen Quynh Ngoc Liamsuwan Thiansin Tran Hoai-Nam 《Journal of Radioanalytical and Nuclear Chemistry》2019,321(1):313-321
Journal of Radioanalytical and Nuclear Chemistry - Simulated workplace neutron fields of a $$^{241}$$ Am–Be source moderated by polyethylene spheres have been developed. The characterization... 相似文献
43.
Rapid and efficient method for the quantification of lychnopholide in rat plasma by liquid chromatography–tandem mass spectrometry for pharmacokinetic application 下载免费PDF全文
Larissa Lachi‐Silva João Paulo Barreto Sousa Maiara Camotti Montanha Sherwin K. B. Sy João Luis Callegari Lopes Denise Brentan Silva Norberto Peporine Lopes Andréa Diniz Elza Kimura 《Biomedical chromatography : BMC》2016,30(7):1092-1096
Lychnopholide is a sesquiterpene lactone usually obtained from Lychnophora and Eremanthus species and has pharmacological activities that include anti‐inflammatory and anti‐tumor. Lychnopholide isolated from Eremanthus matogrossenssis was analyzed in this study. The aims of this study were to develop and validate an analytical methodology by LC‐MS/MS and to quantify lychnopholide in rat plasma. Chromatographic separation was achieved on a C18 column using isocratic elution with the mobile phase consisting of methanol and water (containing 0.1% formic acid) at a flow rate of 0.4 mL/min. The detection was performed in multiple‐reaction monitoring mode using electrospray ionization in positive mode. The method validation was performed in accordance with regulatory guidelines and the results met the acceptance criteria. The linear range of detection was 10–200 ng/mL (r > 0.9961). The intra‐ and inter‐day assay variability were <6.2 and <11.7%, respectively. The extraction recovery was approximately 63% using liquid–liquid extraction with chloroform. Lychnopholide was detected in plasma up to 60 min after intravenous administration in rats. This rapid and sensitive method for the analysis of the sesquiterpene lactone lychnopholide in rat plasma can be applied to pharmacokinetic studies of this compound. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
44.
Importance of Outer‐Sphere and Aggregation Phenomena in the Relaxation Properties of Phosphonated Gadolinium Complexes with Potential Applications as MRI Contrast Agents 下载免费PDF全文
Dr. Mourad Elhabiri Dr. Sabah Abada Mohamadou Sy Dr. Aline Nonat Dr. Philippe Choquet Dr. David Esteban‐Gómez Dr. Claudio Cassino Dr. Carlos Platas‐Iglesias Prof. Mauro Botta Dr. Loïc J. Charbonnière 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(17):6535-6546
A series composed of a tetra‐, a tris‐ and a bisphosphonated ligand based on a pyridine scaffold ( L4 , L3 and L2 , respectively) was studied within the frame of lanthanide (Ln) coordination. The stability constants of the complexes formed with lanthanide cations (Ln=La, Nd, Eu, Gd, Tb, Er and Lu) were determined by potentiometry in aqueous solutions (25.0 °C, 0.1 M NaClO4), showing that the tetraphosphonated complexes are among the most stable LnIII complexes reported in the literature. The complexation of L4 was further studied by different titration experiments using mass spectrometry and various spectroscopic techniques including UV/Vis absorption, and steady state and time‐resolved luminescence (Ln=Eu and Tb). Titration experiments confirmed the formation of highly stable [Ln L4 ] complexes. 31P NMR experiments of the Lu L4 complex revealed an intramolecular interconversion process which was studied at different temperatures and was rationalized by DFT modelling. The relaxivity properties of the GdIII complexes were studied by recording their 1H NMRD profiles at various temperatures, by temperature dependent 17O NMR experiments (Gd L4 ) and by pH dependent relaxivity measurements at 0.47 T (Gd L3 and Gd L2 ). In addition to the high relaxivity values observed for all complexes, the results showed an important second‐sphere contribution to relaxivity and pH dependent variations associated with the formation of aggregates for Gd L2 and Gd L3 . Finally, intravenous injection of Gd L4 to a mouse was followed by dynamic MRI imaging at 1.5 T, which showed that the complex can be immediately found in the blood stream and rapidly eliminated through the liver and in large part through the kidneys. 相似文献
45.
Sy D. Friedman 《Proceedings of the American Mathematical Society》2006,134(6):1823-1824
We show that ``saturation' of the universe with respect to forcing over with partial orders on is equivalent to the existence of .
46.
Using the scale transform of a discrete time signal we define a new family of linear systems. We focus on a particular case related to function theory in the bidisk. To cite this article: D. Alpay, M. Mboup, C. R. Acad. Sci. Paris, Ser. I 347 (2009). 相似文献
47.
48.
1. IntroductionOne of the more challenging aspects of mathematical biology is competition modelling.Although the mathematical idea is simple[1], this type of modelling is so difficult to carryout in any generality since there are so maily ways for a population to compete.The simplest form of competition is called eXPloitative competition. This occurs whenone or more populations compete for the same resources such as a common food supplyor a growth-limiting nutriellt. A simple example of this… 相似文献
49.
为了解决一些收敛定理,我们给出基于半环([0,1],, )的伪可加分解测度的积分这种模糊积分被深入研究.在给出这种积分的性质的基础上,我们得到一些收敛定理,它们是经典收敛定理的扩张,同时我们得到关于这种模糊测度的Egorof定理. 相似文献
50.
In this work, we study the existence, uniqueness and exponential stability in mean square of mild solutions for some stochastic neutral partial functional integrodifferential equations with delays and Poisson jumps. Sufficient conditions for the existence and exponential stability in mean square of mild solutions are derived by means of the Banach fixed point principle. We suppose that the linear part has a resolvent operator in the sense given in Grimmer (Trans. Am. Math. Soc., 273(1):333–349, 1982). An example is provided to illustrate the results of this work. 相似文献