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61.
Coan TE Gao YS Liu F Maravin Y Stroynowski R Artuso M Boulahouache C Blusk S Bukin K Dambasuren E Moneti GC Mountain R Muramatsu H Nandakumar R Skwarnicki T Stone S Wang JC Mahmood AH Csorna SE Danko I Bonvicini G Cinabro D Dubrovin M McGee S Bornheim A Lipeles E Pappas SP Shapiro A Sun WM Weinstein AJ Briere RA Chen GP Ferguson T Tatishvili G Vogel H Adam NE Alexander JP Berkelman K Boisvert V Cassel DG Drell PS Duboscq JE Ecklund KM Ehrlich R Galik RS Gibbons L Gittelman B Gray SW Hartill DL 《Physical review letters》2003,90(10):101801
Using 13.8 fb(-1) of data collected at or just below the Upsilon(4S) with the CLEO detector, we report the result of a search for the flavor changing neutral current process D0-->gammagamma. We observe no significant signal for this decay mode and determine 90% confidence level upper limits on the branching fractions B(D0-->gammagamma)/B(D0-->pi(0)pi(0))<0.033 and B(D0-->gammagamma)<2.9 x 10(-5). 相似文献
62.
Michael Koch Mahmood Saleem Gernot Krammer 《Particle & Particle Systems Characterization》2007,24(6):431-439
The measurement of a distributed property is frequently encountered in engineering applications. The impact of a possible measurement error on the measured distribution is described and two methods to account for such an error are detailed: A Fourier transform based deconvolution procedure and a moment based deconvolution approach via kernel estimators are presented. The deconvolution methods can be used in many particle characterization and process applications where particle features or properties are commonly presented in a distributed form. In the current instance, these methods are carefully explored by using artificially generated data and applied to experimental data obtained from filter cake thickness measurements. 相似文献
63.
References: 《理论物理通讯》2007,47(5):829-834
It has been pointed out by Hall et al. [Gen. Rel. Gray. 28 (1996) 299.] that matter collineations can be defined by using three different methods. But there arises the question whether one studies matter collineations by using LεTab=0, or LεT^ab = 0 or LεT^b a=0. These alternative conditions are, of. course, not generally equivalent. This problem has been explored by applying these three definitions to general static spherically symmetric spacetimes. We compare the results with each definition. 相似文献
64.
65.
Elia Merzari H. Ninokata A. Mahmood M. Rohde 《Theoretical and Computational Fluid Dynamics》2009,23(5):333-351
Geometries containing a narrow gap are characterized by strong quasi-periodical flow oscillations in the narrow gap region.
The above mentioned phenomena are of inherently unstable nature and, even if no conclusive theoretical study on the subject
has been published, the evidence shown to this point suggests that the oscillations are connected to interactions between
eddy structures of turbulent flows on opposite sides of the gap. These coherent structures travel in the direction of homogeneous
turbulence, in a fashion that strongly recalls a vortex street. Analogous behaviours have been observed for arrays of arbitrarily
shaped channels, within certain range of the geometric parameters. A modelling for these phenomena is at least problematic
to achieve since they are turbulence driven. This work aims to address the use of Proper Orthogonal Decomposition (POD) to
reduce the Navier–Stokes equations to a set of ordinary differential equations and better understand the dynamics underlying
these oscillations. Both experimental and numerical data are used to carry out the POD. 相似文献
66.
Visible‐light‐driven photocatalytic degradation of fenpyroximate in rotating packed bed reactor using Fe3O4@PbS@Ni2P magnetic nanocomposite photocatalyst: Response surface modelling and optimization 下载免费PDF全文
67.
68.
An efficient experimentally simple and inexpensive catalyst system for the selective amidation of aryl iodides using 15 mol% of CuI as catalyst, 15 mol% of L-proline as ligand and KF/Al2O3 as a base in toluene is described. 相似文献
69.
Abedinifar Fahimeh Babazadeh Rezaei Elham Biglar Mahmood Larijani Bagher Hamedifar Halleh Ansari Samira Mahdavi Mohammad 《Molecular diversity》2021,25(4):2571-2604
Molecular Diversity - Thiophene-based analogs have been fascinated by a growing number of scientists as a potential class of biologically active compounds. Furthermore, they play a vital role for... 相似文献
70.
Novel Osmium‐based Coordination Complexes as Photosensitizers for Panchromatic Photodynamic Therapy 下载免费PDF全文
Savo Lazic Pavel Kaspler Ge Shi Susan Monro Tariq Sainuddin Sarah Forward Kamola Kasimova Robie Hennigar Arkady Mandel Sherri McFarland Lothar Lilge 《Photochemistry and photobiology》2017,93(5):1248-1258
Cancer remains a major global malaise requiring the advent of new, efficient and low‐cost treatments. Photodynamic therapy, which combines a photosensitizer and photons to produce cytotoxic reactive oxygen species, has been established as an effective cancer treatment but has yet to become mainstream. One of the main limitations has been the paucity of photosensitizers that are effective over a wide range of wavelengths, can exert their cytotoxic effects in hypoxia, are easily synthesized and produce few if any side effects. To address these shortfalls, three new osmium‐based photosensitizers (TLD1822, TLD1824 and TLD1829) were synthesized and their photophysical and photobiological attributes determined. These photosensitizers are panchromatic (i.e. black absorbers), activatable from 200 to 900 nm and have strong resistance to photobleaching. In vitro studies show photodynamic therapy efficacy with both red and near‐infrared light in normoxic and hypoxic conditions, which translated to good in vivo efficacy of TLD1829 in a subcutaneous murine colon cancer model. 相似文献