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81.
Sun R Colin E Ajitanand NN Alexander JM Barton MA DeYoung PA Drake KL Elmaani A Gelderloos CJ Gualtieri EE Guinet D Hannuschke S Jaasma JA Kowalski L Lacey RA Lauret J Norbeck E Pak R Peaslee GF Stern M Stone NT Sundbeck SD Vander Molen AM Westfall GD Yang LB Yee J 《Physical review letters》2000,84(1):43-46
For central collisions of (17-115)A MeV 40Ar+Cu, Ag, Au, an overall balance is determined for the average mass, energy, and longitudinal momentum. Light charged particles and fragments are separated into forward-focused and isotropic components in the frame of the heaviest fragment. Energy removal by the isotropic component reaches 1-2 GeV. For such high deposition energies, statistical multifragmentation models predict much more extensive nuclear disassembly than is observed. 相似文献
82.
Fujiwara M Akimune H van Den Berg AM Cribier M Daito I Ejiri H Fujimura H Fujita Y Goodman CD Hara K Harakeh MN Ihara F Ishikawa T Janecke J Kawabata T Raghavan RS Schwarz K Tanaka M Yamanaka T Yosoi M Zegers RG 《Physical review letters》2000,85(21):4442-4445
Discrete Gamow-Teller (GT) transitions 176Yb-->176Lu at low excitation energies have been measured via the ( 3He,t) reaction at 450 MeV and at 0 degrees. For 176Yb, two low-lying states are observed, setting low thresholds Q(nu) = 301 and 445 keV for neutrino ( nu) capture. Capture rates estimated from the measured GT strengths, the simple two-state excitation structure, and the low Q(nu) in Yb-Lu indicate that Yb-based nu detectors are well suited for a direct measurement of the sub-MeV solar electron-neutrino ( nu(e)) spectrum including pp neutrinos. 相似文献
83.
Li Yang Paul W. May Lei Yin James A. Smith Keith N. Rosser 《Journal of nanoparticle research》2007,9(6):1181-1185
Crystalline carbon nitride nanopowders and nanorods have been successfully synthesized at room temperature and pressure using
the novel technique of pulsed laser ablation of a graphite target in liquid ammonia solution. High-resolution transmission
electron microscopy (HRTEM), selected area electron diffraction (SAED), and Fourier transform infrared spectroscopy (FTIR)
were used to systematically study the morphology, nanostructure and chemical bonding. The experimental composition and structure
of the nanoparticles are consistent with the theoretical calculations for α-C3N4. After 2 h ablation the particles had a size distribution ∼8–12 nm, whereas after 5 h ablation the particles had grown into
nanorod-like structures with a crystalline C3N4 tip. A formation mechanism for these nanorods is proposed whereby nanoparticles are first synthesized via rapid formation
of an embryonic particle, followed by a slow growth, eventually leading to a one-dimensional nanorod structure. 相似文献
84.
Sakari Leino Patrick JC May Paavo Alku Lassi A Liikkanen Hannu Tiitinen 《BMC neuroscience》2007,8(1):78
Background
In the field of auditory neuroscience, much research has focused on the neural processes underlying human sound localization. A recent magnetoencephalography (MEG) study investigated localization-related brain activity by measuring the N1m event-related response originating in the auditory cortex. It was found that the dynamic range of the right-hemispheric N1m response, defined as the mean difference in response magnitude between contralateral and ipsilateral stimulation, reflects cortical activity related to the discrimination of horizontal sound direction. Interestingly, the results also suggested that the presence of realistic spectral information within horizontally located spatial sounds resulted in a larger right-hemispheric N1m dynamic range. Spectral cues being predominant at high frequencies, the present study further investigated the issue by removing frequencies from the spatial stimuli with low-pass filtering. This resulted in a stepwise elimination of direction-specific spectral information. Interaural time and level differences were kept constant. The original, unfiltered stimuli were broadband noise signals presented from five frontal horizontal directions and binaurally recorded for eight human subjects with miniature microphones placed in each subject's ear canals. Stimuli were presented to the subjects during MEG registration and in a behavioral listening experiment. 相似文献85.
86.
George Eng Pamela K. McKinney-Forbes Kristy L. Richie Van V. Nguyen
Leopold May
《Journal of organometallic chemistry》1986,310(3):285-291To obtain more structural information on complexes formed between alkyltin halides and bidentate ligands, the solid-state IR and Mössbauer spectra of the 1,2-ethanediamine and 1,4-butanediamine complexes of trimethyltin halides and dimethyltin dihalides were examined. The structures of the trimethyltin halide complexes were found to be trigonal bipyramidal with coplnar methyl groups. The dimethyltin dihalide complexes were octahedral with the methyl groups in the cis-positions and the halides trans to each other. However, there were no differences in the structures of the chloro and bromo complexes of either type. 相似文献
87.
Colloid and Polymer Science - Die gegenseitige Flockung von vier verschiedenen Eisenoxydsolen, deren Konstitution nach Wintgen-Biltz bestimmt worden war, mit acht verschiedenen negativen Solen... 相似文献
88.
89.
W. Simarew S. G. Menefee O. R. Overman A. Gorbatschewa H. Chr Jorgensen I. V. Hunt A. Konoplew H. Fincke C. Ehrlich R. Trommsdorff M. Asdrubali S. Hadwen R. Gwatkin F. K. Neave H. D. Kay W. R. Graham R. Aschaffenburg A. Jepsen P. Madelung Ch. Paley H. Kreker A. M. Williams May Davies S. B. Thomas G. M. Phillips W. M. Ashton G. D. Simons J. Davies B. F. Thomas L. Little H. A. Sirks G. Sjöström P. Jaulmes L. Poujol und J. A. B. Smith 《Fresenius' Journal of Analytical Chemistry》1943,126(7):282-286
Ohne Zusammenfassung 相似文献
90.
May Lee Low Cheang Wei Chan Pei Ying Ng Ing Hong Ooi Mohd Jamil Maah Soi Moi Chye 《Journal of Coordination Chemistry》2017,70(2):223-241
Three ternary copper(II) complexes, [Cu(phen)(L-phe)Cl]·2H2O, [Cu(phen)(L-leu)Cl]·4½H2O, and [Cu(phen)(L-tyr)Cl]·3H2O, and four binary copper(II) complexes, [Cu(phen)Cl2], Cu(L-phe)2·½H2O, Cu(L-leu)2·½H2O, and Cu(L-tyr)2·H2O (where phen = 110-phenanthroline, L-phe = L-phenylalanine, L-tyr = L-tyrosine, L-leu = L-leucine and Cl- = chloride), were synthesized and characterized by elemental analysis, spectroscopic techniques (FTIR, UV–visible, fluorescence spectroscopy), magnetic susceptibility, molar conductivity, and lipophilicity measurement. X-ray diffraction determination of a single crystal of [Cu(phen)(L-tyr)Cl] showed two independent molecules in the asymmetric unit, each with the same distorted square pyramidal geometry about copper(II). p-Nitrosodimethylaniline assay revealed that the three ternary complexes were better inducers of reactive oxygen species over time than binary complexes, CuCl2, and free ligands. All the copper(II) complexes in this series inhibited the three proteolytic activities in the order Trypsin-like > Caspase-like > Chymotrypsin-like. In terms of anticancer properties, the copper(II)-phen complexes had GI50 values of less than 4 μM against MCF-7, HepG2, CNE1 and A549 cancer cell lines, more potent than cisplatin. 相似文献