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Dohrmann F Ahmidouch A Armstrong CS Arrington J Asaturyan R Avery S Bailey K Bitao H Breuer H Brown DS Carlini R Cha J Chant N Christy E Cochran A Cole L Crowder J Danagoulian S Elaasar M Ent R Fenker H Fujii Y Gan L Garrow K Geesaman DF Gueye P Hafidi K Hinton W Juengst H Keppel C Liang Y Liu JH Lung A Mack D Markowitz P Mitchell J Miyoshi T Mkrtchyan H Mtingwa SK Mueller B Niculescu G Niculescu I Potterveld D Raue BA Reimer PE Reinhold J Roche J Sarsour M Sato Y Segel RE Semenov A Stepanyan S 《Physical review letters》2004,93(24):242501
The (3,4)(Lambda)H and (4)(Lambda)H hypernuclear bound states have been observed for the first time in kaon electroproduction on (3,4)He targets. The production cross sections have been determined at Q(2)=0.35 GeV2 and W=1.91 GeV. For either hypernucleus the nuclear form factor is determined by comparing the angular distribution of the (3,4)He(e,e(')K+)(3,4)(Lambda)H processes to the elementary cross section 1H(e,e K+)Lambda on the free proton, measured during the same experiment. 相似文献
304.
Miyoshi T Sarsour M Yuan L Zhu X Ahmidouch A Ambrozewicz P Androic D Angelescu T Asaturyan R Avery S Baker OK Bertovic I Breuer H Carlini R Cha J Chrien R Christy M Cole L Danagoulian S Dehnhard D Elaasar M Empl A Ent R Fenker H Fujii Y Furic M Gan L Garrow K Gasparian A Gueye P Harvey M Hashimoto O Hinton W Hu B Hungerford E Jackson C Johnston K Juengst H Keppel C Lan K Liang Y Likhachev VP Liu JH Mack D Margaryan A Markowitz P Martoff J Mkrtchyan H Nakamura SN Petkovic T Reinhold J Roche J 《Physical review letters》2003,90(23):232502
High-energy, cw electron beams at new accelerator facilities allow electromagnetic production and precision study of hypernuclear structure, and we report here on the first experiment demonstrating the potential of the (e,e'K+) reaction for hypernuclear spectroscopy. This experiment is also the first to take advantage of the enhanced virtual photon flux available when electrons are scattered at approximately zero degrees. The observed energy resolution was found to be approximately 900 keV for the (12)(Lambda)B spectrum, and is substantially better than any previous hypernuclear experiment using magnetic spectrometers. The positions of the major excitations are found to be in agreement with a theoretical prediction and with a previous binding energy measurement, but additional structure is also observed in the core excited region, underlining the future promise of this technique. 相似文献
305.
Yukio-Pegio Gunji Hiroyuki Miyoshi Tatsuji Takahashi Moto Kamiura 《Chaos, solitons, and fractals》2006,27(5):1187-1204
In brain science, there are few researches focusing on the theoretical relation between cognition (top-down processing) and perception (bottom-up processing). Philosophically they were regarded as the alternative leading to the dualism of mind and body, while it is an adequate problem for the endo-physics. Qualia are conjectured as the hard problem under those situations. To overcome such an impasse, we propose an abstract brain model featuring the dynamical duality of two parts of computations in a brain, in a term of endo-physics and internal measurement. Two parts of computations are expressed as binary relations, and the relationship between them is expressed as a pair of maps, called an infomorphism [Barwise J, Seligman J. Information flow, the logic of distributed systems. Cambridge University Press 1997]. Dynamical duality is implemented by the interaction between a binary relation and an infomorphism, and that leads to a dynamical change of a pair of binary relations. When a binary relation is expressed as a partial ordered set, one can check whether a part of computation is closed with respect to logical operations (i.e., a lattice) or not. By estimating a binary relation in terms of properties of lattice, we show that dynamical infomorphism robustly develops to a pair of logical computations corresponding to type cognition and non-logical one corresponding to qualia perception. It implies origin of differentiation and robust co-existence of type-cognition and qualia-perception. It is easy to see that dynamical infomorphism can also develop to a pair of singleton sets corresponding to savants’ special cognitive style. 相似文献
306.
Hiroyuki Yaguchi Seiro Miyoshi Goshi Biwa Masaya Kibune Kentaro Onabe Yasuhiro Shiraki Ryoichi Ito 《Journal of Crystal Growth》1997,170(1-4):353-356
We have investigated the conduction-band-edge formation in GaP1−xNx alloys by nitrogen incorporation into GaP using photoluminescence excitation (PLE) spectroscopy. The PLE spectra of GaP1−xNx alloys with various nitrogen concentrations show that the absorption edge shifts to lower energies with increasing nitrogen concentration. From the nitrogen concentration dependence of the absorption edge energy we found that the conduction-band-edge formation in GaP1−xNx alloys originates from the formation of the A line. 相似文献
307.
The determination of oxygen (0.001–0.2%) in iron and steel by the fast neutron activation method was investigated. The relative standard deviations of the method at oxygen levels of 0.1, 0.01, and 0.001%, were 3, 5, and 30%, respectively. The analytical results of the method were in good agreement with those of the conventional method in the range stated. 相似文献
308.
Nonadecathymidylic acid was synthesized by the block coupling phosphotriester approach on a polymer support. 相似文献
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Yamashiro K Miyoshi K Ishihara R Umeno D Saito K Sugo T Yamada S Fukunaga H Nagai M 《Journal of chromatography. A》2007,1176(1-2):37-42
A chelating porous sheet for use in solid-phase extraction was prepared by radiation-induced graft polymerization and subsequent chemical modifications. An epoxy-group-containing vinyl monomer was graft-polymerized onto a porous sheet made of polyethylene. The produced epoxy group of the graft chain was converted into an iminodiacetate group. The chelating porous sheet with a density of the iminodiacetate group of 2.1 mol/kg was cut into disks 13 mm in diameter to fit an empty cylindrical cartridge with a capacity of 6 mL. Breakthrough curves using the chelating-porous-disk-packed cartridge overlapped irrespective of the flow rate of the solution ranging up to 1500 mL/h because of negligible diffusional mass-transfer resistance of the copper ions to the iminodiacetate group of the graft chain. 相似文献