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91.
P. Jenni P. Baillon C. Bricman M. Ferro-Luzzi J.M. Perreau R.D. Tripp T. Ypsilantis Y. Declais J. Seguinot 《Nuclear Physics B》1976,105(1):1-22
The differential cross sections of the combined elastic and break-up K?d reaction have been measured at 1.21, 1.42 and 2.61 GeV/c incident K? momentum. The measurements have been performed at the CERN PS using multiwire proportional chambers. The values of the invariant momentum transfer t explored (0.0005<|t|<0.1 GeV2) include the Coulomb-nuclear interference region. The differential cross sections have been analysed in the framework of the Glauber impact-parameter formalism. The observed interference effects have been used to derive the ratio of the real to imaginary part of the forward K?n nuclear amplitude. 相似文献
92.
The decomposition of formic acid vapor by 2.783 μm infrared radiation from a pulsed HF laser has been studied at pressures from 1.6 to 44 torr temper 相似文献
93.
An examination of the results of measurements of the forward and reverse rate constants for the reaction shows that agreement between the kinetics and the thermochemistry is achieved only through use of a value of ΔHf(C2H5) = 28 kcal mol?1. This system therefore provides further support for the recent measurement of this quantity. 相似文献
94.
M. H. Back 《国际化学动力学杂志》1970,2(5):409-418
Rate constants for the bimolecular reactions of ethylene and propylene to form radicals and to form cyclobutane or its derivatives have been calculated using thermodynamic and kinetic data. Comparison of these rates with the kinetics of the thermal reactions of ethylene and propylene show that cyclobutane and its derivatives are probably not important intermediates in the processes forming radicals. 相似文献
95.
96.
97.
Jiang CL Esbensen H Rehm KE Back BB Janssens RV Caggiano JA Collon P Greene J Heinz AM Henderson DJ Nishinaka I Pennington TO Seweryniak D 《Physical review letters》2002,89(5):052701
The excitation function for fusion evaporation in the (60)Ni+ (89)Y system was measured over a range in cross section covering 6 orders of magnitude. The cross section exhibits an abrupt decrease at extreme sub-barrier energies. This behavior, which is also present in a few other systems found in the literature, cannot be reproduced with present models, including those based on a coupled-channels approach. Possible causes are discussed, including a dependence on the intrinsic structure of the participants. 相似文献
98.
Back BB Baker MD Barton DS Betts RR Bindel R Budzanowski A Busza W Carroll A Decowski MP Garcia E George N Gulbrandsen K Gushue S Halliwell C Heintzelman GA Henderson C Hofman DJ Hołyński R Holzman B Johnson E Kane JL Katzy J Khan N Kucewicz W Kulinich P Lin WT Manly S McLeod D Michałowski J Mignerey AC Mülmenstädt J Nouicer R Olszewski A Pak R Park IC Pernegger H Reed C Remsberg LP Reuter M Roland C Roland G Rosenberg L Sarin P Sawicki P Skulski W Steadman SG Steinberg P Stephans GS 《Physical review letters》2001,87(10):102303
The charged-particle pseudorapidity density dN(ch)/d eta has been measured for Au+Au collisions at sqrt[s(NN)] = 130 GeV at RHIC, using the PHOBOS apparatus. The total number of charged particles produced for the 3% most-central Au+Au collisions for /eta/相似文献
99.
Yanjia Lu C. L. Chakrabarti M. H. Back D. C. Grégoire W. H. Schroeder 《International journal of environmental analytical chemistry》2013,93(2-4):313-337
Abstract Kinetic studies of uptake of metal ions by the Chelex batch technique were made to determine Cd, Cu and Pb speciation in model solutions, a snow sample and a river surface water sample. Inductively-coupled plasma mass spectrometry (ICP-MS) and graphite furnace atomic absorption spectrometry (GFAAS) were used for direct determination of these metals. ICP-MS with the solution nebulization technique minimized contamination and adsorption problems involved in the discrete sampling technique of GFAAS, and hence, gave more precise and accurate results. Also, ICP-MS allowed collection of many more data points than GFAAS and was able to resolve components with similar rates of dissociation, which could not always be resolved by GFAAS with its discrete sampling technique. ICP-MS was therefore preferable to GFAAS for kinetic studies of metal speciation. The kinetic data were analyzed by the iterative deconvolution method. The applicability of the Chelex batch technique to metal speciation was validated by analysis of model solutions containing these metal ions with or without EDTA, NTA and fulvic acid. Use of the Chelex batch technique for Cd, Cu and Pb speciation in snow and river surface water samples revealed a number of kinetically distinguishable components of these metals (as complexes) ranging from one to three, probably present as aquo ions or inorganic complexes in the snow sample, and bound to macromolecules/and or colloidal materials in the river surface water sample. 相似文献
100.
Jenni E. Koskela Sanna Turunen Laura Ylä‐Outinen Susanna Narkilahti Minna Kellomäki 《先进技术聚合物》2012,23(6):992-1001
Two‐photon polymerization (2PP) is a versatile microfabrication tool for biomedical applications as it provides unparalleled resolution for accurate three‐dimensional (3D) replication of biological microstructures. To widen the selection of biomaterials suitable for 2PP, this paper presents the processing of a methacrylated poly(ε‐caprolactone)‐based oligomer (PCL‐o) and a poly(ethylene glycol) diacrylate (PEGda) hydrogel into microstructures. PCL‐o is a novel biodegradable photopolymer that has not been previously processed with 2PP, and the fabrication of both polymers with an Nd:YAG laser is reported here for the first time. The overall 2PP processability and achievable resolution were studied by polymerizing arbitrary microstructures on glass substrates. The samples were characterized with scanning electron microscopy. Additionally, the effect of photoinitiator concentration on the resolution was investigated. Also, a preliminary cell attachment test was performed with UV cured films in order to investigate the impact of the used material–initiator combination on cell viability and migration. As a result, laser‐induced polymerization of both PCL‐o and PEGda was successfully demonstrated, and the Nd:YAG laser was proven adequate for the 2PP processing of the novel biodegradable photoresist. Resolution in the order of 1 µm was achieved with PCL‐o. With the easy processing of both PEGda and PCL‐o, these materials have great potential for different biomedical applications. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献