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241.
Jaroslaw Wlodarczyk 《Journal of the American Mathematical Society》2005,18(4):779-822
Building upon work of Villamayor and Bierstone-Milman we give a proof of the canonical Hironaka principalization and desingularization. The idea of ``homogenized ideals" introduced in the paper gives a priori the canonicity of the algorithm and radically simplifies the proof.
242.
Comparative molecular surface analysis: A novel tool for drug design and molecular diversity studies
The application of the SOM network in drug design and molecular diversity is discussed. In particular, examples of the applications of the Comparative Molecular Surface Analysis (CoMSA) are reviewed. Molecular surface is a fuzzy category, inspired by the macroscopic world, which has no unique equivalent in the molecular scale. However, it is somewhere near the area where the molecular recognition processes are taking place. Consequently, the methods that analyze this region promise better efficiency than procedures that are based on uniform grids. An important advantage of the CoMSA method is the possibility for the generation of fuzzy molecular representations together with its ability to discover such aspects of molecular similarity that can be easily overlooked by a chemist. The ability for data compression is a further advantage. It has also been shown that the fast processing of the comparative Kohonen mapping enables one to implement this method in the field of molecular diversity. 相似文献
243.
Length of extremal rays and generalized adjunction 总被引:5,自引:0,他引:5
Jaroslaw A. Wiśniewski 《Mathematische Zeitschrift》1989,200(3):409-427
244.
Grobelny Jaroslaw Pradeep Namboodiri Kim Doo-In 《Journal of nanoparticle research》2008,10(1):163-171
In this research, we have studied the doping behaviors of eight transition metal ion dopants on the crystal phase, particle
sizes, XRD patterns, adsorption spectra, anatase fraction, and photoreactivity of TiO2 nanoparticles. The pristine and ion-doped TiO2 nanoparticles of 15.91-25.47 nm were prepared using sol–gel method. Test metal ion concentrations ranged from 0.00002 to
0.2 at.%. The absorption spectra of the TiO2 nanoparticles were characterized using UV-Visible spectrometer. The wavelength of the absorption edge of TiO2 was estimated using the spectra derivative-tangent method. The photoreactivities of pristine and ion-doped TiO2 nanoparticles under UV irradiation were quantified by the decoloring rate of methyl orange. XRD patterns were recorded using
a Rigaku D/MAX-2500 V diffractometer with Cu Kα radiation (50 kV and 250 mA), and particle size and anatase fraction were
calculated. Results reveal that different ion doping exhibited complex effects on the studied characteristics of TiO2 nanoparticles. In general, red shift occurred to ion-doped TiO2 nanoparticles, but still with higher TiO2 photoreactivities when doped with Fe3+ and Ni2+ ions. Among the ions investigated, Ni-doped TiO2 nanoparticles have shown highest photoreactivity at the concentration of 0.002 at.%, about 1.9 times that of the pristine
TiO2. Ion doping was shown to reduce the diameter and influence the fraction of anatase. Data also indicated that the combination
of anatase diameter and ion radius might play an important role in the photoreactivity of TiO2 nanoparticles. This investigation contributes to the understanding of complex ion doping effects on TiO2 nanoparticles, and provides references for enhancing their environmental application. 相似文献
245.
Jablin MS Zhernenkov M Toperverg BP Dubey M Smith HL Vidyasagar A Toomey R Hurd AJ Majewski J 《Physical review letters》2011,106(13):138101
Polymer-supported single lipid bilayers are models to study configurations of cell membranes. We used off-specular neutron scattering to quantify in-plane height-height correlations of interfacial fluctuations of such a lipid bilayer. As temperature decreased from 37 °C to 25 °C, the polymer swells and the polymer-supported lipid membrane deviates from its initially nearly planar structure. A correlation length characteristic of capillary waves changes from 30 μm at 37 °C to 11 μm at 25 °C, while the membrane bending rigidity remains roughly constant in this temperature range. 相似文献
246.
Bak A Magdziarz T Kurczyk A Polanski J 《Combinatorial chemistry & high throughput screening》2011,14(7):560-569
A detailed knowledge of hydrogen bond geometry and its directional preferences is vital for in silico investigations of the ligand-receptor short-range non-covalent interactions. The spatial arrangement of the carbonyl and hydroxyl groups seems to determine the capability of β-ketoenol derivatives to recognize the surrounding environment by forming inter- and intra-molecular hydrogen bonds (IHB). In the current study we examined the application of the MoStBioDat platform for a massive database screening of the IHB motifs in β-ketoenol subunits (O=C-C=C-OH). Then, the virtual 3D structural data derived from ZINC and PubChem repository were compared to the experimentally determined CSD data. Differences specific for each database were discovered, which indicated inaccuracies in the simulated data. 相似文献
247.
Danuta Kaczmarek Damian Wojcieszak Jaroslaw Domaradzki Eugeniusz Prociow Frank Placido Steffen Lapp Rafal Dylewicz 《Central European Journal of Physics》2011,9(2):349-353
In this work, the influence of Tb-doping on structure, and especially hardness of nanocrystalline TiO2 thin films, has been described. Thin films were formed by a high-energy reactive magnetron sputtering process in a pure oxygen
atmosphere. Undoped TiO2-matrix and TiO2:Tb (2 at. % and 2.6 at. %) thin films, had rutile structure with crystallite sizes below 10 nm. The high-energy process produces
nanocrystalline, homogenous films with a dense and close packed structure, that were confirmed by X-ray diffraction patterns
and micrographs from a scanning electron microscope. Investigation of thin film hardness was performed with the aid of a nanoindentation
technique. Results of measurements have shown that the hardness of all manufactured nanocrystalline films is above 10 GPa.
In the case of undoped TiO2 matrix, the highest hardness value was obtained (14.3 GPa), while doping with terbium results in hardness decreasing down
to 12.7 GPa and 10.8 GPa for TiO2:(2 at. % Tb) and TiO2:(2.6 at. % Tb) thin films, respectively. Incorporation of terbium into TiO2-matrix also allows modification of the elastic properties of the films. 相似文献
248.
Damian Wojcieszak Danuta Kaczmarek Jaroslaw Domaradzki Eugeniusz L. Prociow Antoni W. Morawski Magdalena Janus 《Central European Journal of Physics》2011,9(2):354-359
In this work photocatalytic properties of TiO2 thin films doped with different amount of Tb have been described. Thin films were prepared by high energy reactive magnetron
sputtering process. Comparable photocatalytic activity has been found for all doped TiO2 thin films, while different amounts of Tb dopant (0.4 and 2.6 at. %) results in either an anatase or rutile structure. It
was found that the terbium dopant incorporated into TiO2 was also responsible for the amount of hydroxyl groups and water particles adsorbed on the thin film surfaces and thus photocatalytic
activity was few times higher in comparison with results collected for undoped TiO2 thin films. 相似文献
249.
Jaroslaw Kiegiel Christian Chapuis Zofia Urbaczyk-Lipkowska Janusz Jurczak 《Helvetica chimica acta》1998,81(9):1672-1680
Cycloadditions of 1-methoxybuta-1,3-diene to (2R)-N-pyruvoyl and (2R)-N-(phenylglyoxyloyl)bornane-10,2-sultam ((−)- 1b and (−)- 1c , resp.) under high-pressure conditions are presented. The absolute configurations of the cycloadducts 2b,c and of their resulting reduced alcohols 3b,c are based on their X-ray analyses. The stereochemical course of these reactions is discussed and compared to the inverse diastereoselectivity observed for the analogous cycloaddition to (2R)-N-glyoxyloylbornane-10,2-sultam ( 1a ) 相似文献
250.
Martin Goez Jaroslaw Rozwadowski Bronislaw Marciniak 《Angewandte Chemie (International ed. in English)》1998,37(5):628-630
Cyclic radical cations Met-(S…︁█ + N) of methionine could play an important role in processes such as long-range electron transfer across cell membranes and oxidative damage to cells. CIDNP spectroscopy (CIDNP = chemically induced dynamic nuclear polarization) furnishes direct structural proof and allows experimental investigation of the spin-density distribution in the two-center three-electron bonds. 相似文献