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101.
Jones G. T. Jones R. W. L. Kennedy B. W. Klein H. Morrison D. R. O. Wachsmuth H. Miller D. B. Mobayyen M. M. Wainstein S. Aderholz M. Hantke D. Katz U. F. Kern J. Schmitz N. Wittek W. Borner H. P. Myatt G. Cooper-Sarkar A. M. Guy J. Venus W. Bullock F. W. Burke S. 《Zeitschrift fur Physik C Particles and Fields》1994,63(4):601-609
Zeitschrift für Physik C Particles and Fields - A set of proton longitudinal polarized distributions, worked out under the assumption of small gluon polarization, is used to evaluate several... 相似文献
102.
E. A. Katz 《Physics of the Solid State》2002,44(4):647-651
This paper reviews the prospects of fullerene-based materials for photovoltaics. The device structure and parameters of inorganic and organic fullerene-based solar cells are presented. An additional promising direction of solar energy utilization—the production of fullerenes and carbon nanotubes by concentrated sun-light—is also discussed. 相似文献
103.
F. W. Aston Cecil H. Cribb Richard Reik und J. Katz 《Fresenius' Journal of Analytical Chemistry》1902,41(8):503-504
Ohne Zusammenfassung 相似文献
104.
We study the effects caused by remote boundaries on soliton dynamics in nonlinear media with a large range of nonlocality, and demonstrate theoretically and experimentally how asymmetric boundary forces can lead to soliton steering and oscillation in predetermined trajectories. 相似文献
105.
Greer BJ Michaelis VK Katz MJ Leznoff DB Schreckenbach G Kroeker S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(13):3609-3618
A series of lead(II) coordination polymers containing [N(CN)2]? (DCA) or [Au(CN)2]? bridging ligands and substituted terpyridine (terpy) ancillary ligands ([Pb(DCA)2] ( 1 ), [Pb(terpy)(DCA)2] ( 2 ), [Pb(terpy){Au(CN)2}2] ( 3 ), [Pb(4′‐chloro‐terpy){Au(CN)2}2] ( 4 ) and [Pb(4′‐bromo‐terpy)(μ‐OH2)0.5{Au(CN)2}2] ( 5 )) was spectroscopically examined by solid‐state 207Pb MAS NMR spectroscopy in order to characterise the structural and electronic changes associated with lead(II) lone‐pair activity. Two new compounds, 2 and [Pb(4′‐hydroxy‐terpy){Au(CN)2}2] ( 6 ), were prepared and structurally characterised. The series displays contrasting coordination environments, bridging ligands with differing basicities and structural and electronic effects that occur with various substitutions on the terpyridine ligand (for the [Au(CN)2]? polymers). 207Pb NMR spectra show an increase in both isotropic chemical shift and span (Ω) with increasing ligand basicity (from δiso=?3090 ppm and Ω=389 ppm for 1 (the least basic) to δiso=?1553 ppm and Ω=2238 ppm for 3 (the most basic)). The trends observed in 207Pb NMR data correlate with the coordination sphere anisotropy through comparison and quantification of the Pb? N bond lengths about the lead centre. Density functional theory calculations confirm that the more basic ligands result in greater p‐orbital character and show a strong correlation to the 207Pb NMR chemical shift parameters. Preliminary trends suggest that 207Pb NMR chemical shift anisotropy relates to the measured birefringence, given the established correlations with structure and lone‐pair activity. 相似文献
106.
Ogino I Nigra MM Hwang SJ Ha JM Rea T Zones SI Katz A 《Journal of the American Chemical Society》2011,133(10):3288-3291
New material UCB-1 is synthesized via the delamination of zeolite precursor MCM-22 (P) at pH 9 using an aqueous solution of cetyltrimethylammonium bromide, tetrabutylammonium fluoride, and tetrabutylammonium chloride at 353 K. Characterization by powder X-ray diffraction, transmission electron microscopy, and nitrogen physisorption at 77 K indicates the same degree of delamination in UCB-1 as previously reported for delaminated zeolite precursors, which require a pH of greater than 13.5 and sonication in order to achieve exfoliation. UCB-1 consists of a high degree of structural integrity via (29)Si MAS NMR and Fourier transform infrared spectroscopies, and no detectable formation of amorphous silica phase via transmission electron microscopy. Porosimetry measurements demonstrate a lack of hysteresis in the N(2) adsorption/desorption isotherms and macroporosity in UCB-1. The new method is generalizable to a variety of Si:Al ratios and leads to delaminated zeolite precursor materials lacking amorphization. 相似文献
107.
Gromov’s celebrated systolic inequality from ’83 is a universal volume lower bound in terms of the least length of a noncontractible
loop in M. His proof passes via a strongly isometric imbedding called the Kuratowski imbedding, into the Banach space of bounded functions
on M. We show that the imbedding admits an approximation by a (1+e){(1+\epsilon)}-bi-Lipschitz (onto its image), finite-dimensional imbedding for every ${\epsilon > 0}${\epsilon > 0}, using the first variation formula and the mean value theorem. 相似文献
108.
Li Z Rosenbaum MA Venkataraman A Tam TK Katz E Angenent LT 《Chemical communications (Cambridge, England)》2011,47(11):3060-3062
We developed a bacteria-based AND logic gate using a Pseudomonas aeruginosa lasI/rhlI double mutant with two quorum-sensing signaling molecules as the input signals. We showed a distinct electrical output signal, despite the complexity and continuous regulation of metabolic reactions of living cells. 相似文献
109.
Measurements of the tip leakage vortex structures and turbulence in the meridional plane of an axial water-jet pump 总被引:2,自引:0,他引:2
Particle image velocimetry (PIV) measurements at varying resolutions focus on the flow structures in the tip region of a water-jet
pump rotor, including the tip-clearance flow and the rollup process of a tip leakage vortex (TLV). Unobstructed views of these
regions are facilitated by matching the optical refractive index of the transparent pump with that of the fluid. High-magnification
data reveal the flow non-uniformities and associated turbulence within the tip gap. Instantaneous data and statistics of spatial
distributions and strength of vortices in the rotor passage reveal that the leakage flow emerges as a wall jet with a shear
layer containing a train of vortex filaments extending from the tip of the blade. These vortices are entrained into the TLV,
but do not have time to merge. TLV breakdown in the aft part of the blade passage further fragments these structures, increasing
their number and reducing their size. Analogy is made between the circumferential development of the TLV in the blade passage
and that of the starting jet vortex ring rollup. Subject to several assumptions, these flows display similar trends, including
conditions for TLV separation from the shear layer feeding vorticity into it. 相似文献
110.