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121.
The thermodynamic properties of the liquid Ag-Sb alloys were determined using solid oxide galvanic cells with zirconia electrolyte. The emfs of the cells:
122.
Bronowska A Chilmonczyk Z Leś A Edvardsen O Ostensen R Sylte I 《Journal of computer-aided molecular design》2001,15(11):1005-1023
In the present study experimentally determined ligand selectivity of three methylated buspirone analogues (denoted as MM2, MM5 and P55) towards 5-HT1A and 5-HT2A serotonin receptors was theoretically investigated on a molecular level. The relationships between the ligand structure and 5-HT1A and 5-HT2A receptor affinities were studied and the results were found to be in agreement with the available site-directed mutagenesis and binding affinity data. Molecular dynamics (MD) simulations of ligand-receptor complexes were performed for each investigated analogue, docked twice into the central cavity of 5-HT1A/5-HT2A, each time in a different orientation. Present results were compared with our previous theoretical results, obtained for buspirone and its non-methylated analogues. It was found that due to the presence of the methyl group in the piperazine ring the ligand position alters and the structure of the ligand-receptor complex is modified. Further, the positions of derivatives with pyrimidinyl aromatic moiety and quinolinyl moiety are significantly different at the 5-HT2A receptor. Thus, methylation of such derivatives alters the 3D structures of ligand-receptor complexes in different ways. The ligand-induced changes of the receptor structures were also analysed. The obtained results suggest, that helical domains of both receptors have different dynamical behaviour. Moreover, both location and topography of putative binding sites for buspirone analogues are different at 5-HT1A and 5-HT2A receptors. 相似文献
123.
Stanisaw Gnot Ewaryst Rafajowicz Agnieszka Urbaska-Motyka 《Annals of the Institute of Statistical Mathematics》2001,53(2):370-379
In the paper we consider a random linear model for observations provided by spatially located sensors measuring signals coming from one source. For this model a set of sufficient and complete statistics are found, and it is shown that the maximum likelihood estimators of unknown parameters (characteristics of the source) are functions of those statistics. The problem of nonnegative estimators of variance components of the model is shortly discussed. Comparisons of the mean squared errors of several estimators are given. Numerical example concerning hunting for defects in solar cells is considered in details. 相似文献
124.
Anna Wypych-Stasiewicz Adam Szejgis Agnieszka Chmielewska Adam Bald 《Journal of Molecular Liquids》2007,130(1-3):34-37
The electrical conductivities of NaBPh4, NBu4I, NaI, NaCl, NaBr and NaClO4 have been studied in the mixtures of propan-1-ol with water. The obtained results were analysed using the Fuoss–Justice equation. The individual limiting ionic conductivities of Na+, NBu4+, BPh4−, I−, Cl−, Br−, ClO4− ions have been determined using the Fuoss–Hirsch assumption. The dependencies of the limiting molar conductances Λo and Walden products Λoη versus mixed solvent composition have been discussed. 相似文献
125.
Oxidative-reductive properties on the acid-base surfaces of the oxide compositions Sn-Ce-Rh-O and Zr-Mg-Y-O, active as catalysts in the ketonization of secondary alcohols were determined based on the isopropanol conversion selectivity. The kinetics of isopropanol conversion was measured in the oxygen-free atmosphere. Activation energies for both directions of conversion (dehydration to propylene and dehydrogenation to acetone) were calculated. The results were compared with the kinetics over SnO2 and ZrO2. Both oxide compositions, Sn-Ce-Rh-O and Zr-Mg-Y-O are oxidative-reductive catalysts containing Lewis acid centers. 相似文献
126.
This paper presents part of the larger study on microstructural features of mortars and it's effects on laser cleaning process. It focuses on the influence of surface roughness, porosity and moisture content of mortars on the removal of graffiti by Nd:YAG laser. The properties of this laser are as follows: wavelength (λ) 1.06 μm, energy: 500 mJ per pulse, pulse duration: 10 ns. The investigation shows that the variation of laser fluence with the number of pulses required for the laser cleaning can be divided into two zones, namely effective zone and ineffective zone. There is a linear relationship observed between number of pulses required for laser cleaning and the laser fluence in the effective zone, while the number of pulses required for the laser cleaning is almost constant even though the laser fluence increases in the ineffective zone. Moreover, surface roughness, porosity and moisture content of mortar samples have influence on the laser cleaning process. The effect of these parameters become however negligible at the high level of laser fluence. The number of pulses required for the laser cleaning is low for smooth surface or less porous mortar. Furthermore, the wetness of the samples facilitates the cleaning process. 相似文献
127.
128.
Bogusław Buszewski Agnieszka Ulanowska Tomasz Ligor Natalia Denderz Anton Amann 《Biomedical chromatography : BMC》2009,23(5):551-556
In this study, 38 samples of expired air were collected and analyzed from 20 non‐smoking volunteers, four passive smokers and 14 smokers (21 women and 17 men). Measurements were carried out using solid‐phase microextraction (SPME) as an isolation and preconcentration technique. The determination and identification were accomplished by gas chromatography coupled with mass spectrometry (GC/MS). Our data showed that ca 32% of all identified compounds in the breath of healthy non‐smokers were saturated hydrocarbons. In the breath of smoking and passive smoking volunteers hydrocarbons were predominant, but also present were more exogenous analytes such as furan, acetonitrile and benzene than in the breath of non‐smokers. Acetonitrile, furan, 3‐methylfuran, 2,5‐dimethylfuran, 2‐butanone, octane and decane were identified in breath of smoking and passive smoking persons. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
129.
Let
r
K
a,b
be a complete bipartite multigraph. We show a necessary and sufficient condition for a multigraph
r
K
a,b
to be arbitrarily decomposable into open trails. We extend the results obtained by Balister for complete graphs (Balister
in Probab Comput 10:463–499, 2001). Moreover we show that a multigraph
r
K
a,b
with even r and a ≥ 3 or b ≥ 3 is arbitrarily decomposable into open and closed trails. 相似文献