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81.
B.D. Kern T. Fényes A. Krasznahorkay Zs. Dombrádi S. Brant V. Paar 《Nuclear Physics A》1984,430(2):301-320
The γ-ray spectra of the 96Zi(p, nγ)96Nb reaction have been measured with Ge(Li) detectors at different bombarding proton energies between 1.3 and 5.1 MeV. γγ coincidences were observed at Ep = 4.7 and 5.0 MeV. On the basis of experimental results a level scheme of 96Nb was deduced, and γ-threshold energies and γ-branching ratios were determined. Computed Hauser-Feshbach (p, n′) cross sections have been compared with experimental data obtained from the γ-ray measurements, and level spins and parities have been determined. The energies of 96Nb levels were calculated on the basis of the parabolic rule, derived from the cluster-vibration model. The Racah multipole decomposition method was used also for the theoretical interpretation of several 96Nb multiplet states. 相似文献
82.
K. Sistemich K. Kawade H. Lawin G. Lhersonneau H. Ohm U. Paffrath V. Lopac S. Brant V. Paar 《Zeitschrift für Physik A Hadrons and Nuclei》1986,325(2):139-147
Life-times of low-lying levels in 37 91 Rb54 and 37 93 Rb56 have been determined fromβ ??γ coincidence measurements at the fission-product separator JOSEF. Values oft 1/2=17.0(8) ns and 2.0(2) ns have been obtained for the levels at 1,134 keV in91Rb and 267 keV in93Rb, respectively, and upper limits could be deduced for several other states. Calculations in the frame of IBFM/PTQM have been performed for91Rb, the results of which allow an interpretation of the low-lying levels of this nucleus. For the 1,134 keV level the configuration [πg 9/2?2+] 7/2+ is suggested which lies close to or even below the 9/2 1 + level. The calculated half-life of 14 ns for the 1,134 keV level reproduces well the experimental value. The half-life of the 267 keV level in93Rb favours the assignment ofI π=1/2? to this state over the alternative 3/2?. 相似文献
83.
Silver staining of DNA in polyacrylamide gels 总被引:7,自引:0,他引:7
Brant J. Bassam Gustavo Caetano-Anollés 《Applied biochemistry and biotechnology》1993,42(2-3):181-188
Nucleic acids can be detected at the picogram level using a quick and simple silver staining method (2). Using very thin polyesterbacked
polyacrylamide gels, a further simplified protocol was compared to other widely used silver staining procedures. The improved
protocol described here was the most sensitive, the fastest to perform, and had relatively few steps and reagents. This method
also produced the least number of staining artifacts and offered images of high contrast. 相似文献
84.
85.
Ying Wan Katherine A.M. Creber Brant Peppley V. Tam Bui 《Journal of membrane science》2006,280(1-2):666-674
Some chitosan-based solid electrolyte composite membranes were prepared by incorporating potassium hydroxide as the functional ionic source, using glutaraldehyde as cross-linking agent. A three-layer structure with a porous intermediate layer for each composite membrane was observed using SEM. It was found that the concentration of potassium hydroxide solution used to prepare the composite membranes largely influenced the pore volume, porosity, pore size of the intermediate layer, as well as determined the content of potassium hydroxide inside the composite membranes, whereas the degree of cross-linking of composite membrane did not show notable effects. All composite membranes showed significant decreases in both their Tg and onset thermal degradation temperatures with respect to the solid cross-linked chitosan membranes without containing potassium hydroxide. Potassium hydroxide was found to be located inside the intermediate layer of composite membranes with shapes of bulky or fabric crystals. The crystalline properties of matrices of the composite membranes themselves were remarkably modified after being incorporated with potassium hydroxide and main crystalline peaks of matrices almost disappeared for all composite membranes. 相似文献
86.
87.
V. Paar D. K. Sunko S. Brant M. G. Mustafa R. G. Lanier 《Zeitschrift für Physik A Hadrons and Nuclei》1993,345(4):343-357
Large-scale combinatorial calculations of level densities were performed for selected nuclei using Gaussian polynomial generating function method (GPM). Contrary to the results of previous combinatorial calculations, we find a good agreement of the combinatorial total level densities and Bethe formula. Combinatorial GPM calculations were performed also for spin-dependent level densities and comparison is made with various algebraic formulas. On the basis of our GPM calculations we propose a new phenomenological spin-dependent level density formula, which in the low-spin limit reduces to the spin-dependent formula of Bethe. The new formula (24) is for all spins factorized into the product of total level density and spin distribution function, where the spin distribution function (25) contains an additional spin correction parameter. 相似文献
88.
Gustavo Caetano-Anollés Brant J. Bassam 《Applied biochemistry and biotechnology》1993,42(2-3):189-200
DNA amplification fingerprinting (DAF) is a strategy for genetic typing and mapping that uses one or more very short (≥5 nt)
arbitrary oligonucleotides to direct the enzymatic amplification of discrete portions of a DNA template resulting in a spectrum
of products characteristic of the DNA starting material. Polymorphisms from simple banding patterns are useful as genetic
markers while more complex and informative patterns are suitable for DNA fingerprinting. The use of polyacrylamide gel electrophoresis
and silver staining can adequately resolve the spectrum of DAF products into detailed and reproducible patterns. 相似文献
89.
Use of Micellar-Enhanced Ultrafiltration at Low Surfactant Concentrations and with Anionic-Nonionic Surfactant Mixtures 总被引:1,自引:0,他引:1
Fillipi BR Brant LW Scamehorn JF Christian SD 《Journal of colloid and interface science》1999,213(1):68-80
Micellar-enhanced ultrafiltration is a separation technique which can be used to remove metal ions or dissolved organics from water. Metal ions bind to the surface of negatively charged micelles of an anionic surfactant while organic solutes tend to dissolve or solubilized within the micelles. The mixture is then forced through an ultrafiltration membrane with pore sizes small enough to block passage of the micelles and associated metal ions and/or dissolved organics. Monomeric or unassociated surfactant passes through the membrane and does not contribute to the separation. This paper considers advantages of addition of small concentrations of nonionic surfactant to an anionic surfactant; the resulting anionic-nonionic mixed micelles exhibit negative deviation from ideality of mixing which leads to a smaller fraction of the surfactant being present as monomer and a subsequently larger fraction present in the micellar form. The addition of nonionic surfactant improved the separation of divalent zinc substantially at total concentrations above the critical micelle concentration (cmc) of the anionic surfactant. Both zinc and tert-butylphenol (a nonionic organic solute) show unexpected rejection at surfactant concentrations moderately below the cmc, where micelles are absent. This is considered as due to a higher surfactant concentration in the gel layer adjacent to the membrane where micelles are present. Reduction of this rejection at lower transmembrane pressure drops supports this mechanism. Some rejection of zinc was observed in the absence of surfactant but not of tert-butylphenol, indicating an additional effect of membrane charge for ionic solutes. Copyright 1999 Academic Press. 相似文献
90.
Polyacetylene, (CH)x, has been doped with trimethyloxonium hexachloroantimonate, (CH3)3O+SbCl(1), in dichloromethane and acetonitrile. The maximally doped (CH)x films have moderate conductivities [σRT(CH2Cl2) = 10, σRT(CH3CN) = 0.7 Ω?1 cm?1]. Reactions between 1 and (CH)x CH2Cl2 or CH3CN were followed in situ by 1H nuclear magnetic resonance spectroscopy and x-band electron spin resonance spectroscopy. It was found that the reactions in the two solvents are different. In dichloromethane the dopant is SbCl5, which forms from the decomposition of 1, and doping proceeds by electron removal from (CH)x chains. Based on the ESR signal loss, an estimate can be made of the diffusion rate of SbCl5, into the (CH)x fibrils in CH2Cl2; it is found to be ca. 10?17 cm2/s. In acetonitrile the dopant appears to be either CH3CNCH, H+, CH, or a combination of one or more of these dopants. It is postulated that the CH3CNCH, CH, and/or H+ dopant covalently binds to the (CH)x chain. X-ray photoelectron spectra show that films doped with excess 1 in both solvents have approximately one SbCl per 33 CH units. 相似文献