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51.
Kuang-Yu Hu Jia-An Wuu Ming-Ching Kao Yu-Tien Liu Shou-Hsiung Pai 《Applied biochemistry and biotechnology》1998,73(2-3):231-241
Streptomyces chusanensis ZS-2, isolated from a soil sample in Chusan in Taiwan, was found to produce a new Type II restriction endonuclease. This
restriction enzyme was designated as SchI. The purified enzyme was characterized as having a subunit mol wt of 28 kDa, and
was apparently free from exonuclease activities. It cleaves the phosphodiester bond between the fourth C and the fifth G on
the 5’-CCGCGG-3’ sequence of DNAs, leaving a 2-nucleotide protruding end at its 3’ site. This data suggests that SchI is an
isoschizomer of SacII. In addition, based on the comparison between SchI and SacII regarding reaction parameters, it seems
that SchI is a better choice of restriction enzyme for genetic analysis and mapping. 相似文献
52.
A new method for the synthesis of 3-N-phthaloyl homophenylalanine lactone has been developed and its mechanism was proposed. 相似文献
53.
M.R. Pai 《Journal of Physics and Chemistry of Solids》2006,67(7):1502-1509
The catalytic properties and reduction behavior of mixed metal oxides with nominal compositions of LaxTh1−x(VO3−δ)4, where 0.0 ≤ x ≤ 1.0, have been investigated as a function of the value of x. These compositions were synthesized by ceramic route and characterized using powder X-ray diffraction, differential thermal analysis, and temperature-programmed reduction/oxidation/desorption techniques. The substituted samples were comprised of two distinct phases, one corresponding to tetragonal thorium metavanadate with partial substitution at A-sites, i.e. LaxTh1−x(VO3−δ)4, and the other a new phase identified as LaV4O11+δ. Both these phases exhibited considerable oxygen non-stoichiometry, depending upon the extent of substitution. Nevertheless, no significant change was observed in their respective crystal symmetry. Further, the substituted samples showed more reproducible redox behavior and also an improved catalytic activity for CO oxidation reaction. A definite correlation is found to exist between the micro-structural defects generated in the above-mentioned two phases because of the oxygen ion vacancies, resultant enhancement in thermal diffusitivity of lattice oxygen, and finally the catalytic activity of the substituted mixed oxides. It is envisaged that a kind of synergism between the micro-structural defects existing in the two inter-grown phases generated simultaneously during the synthesis may control the catalytic properties of composite metal oxide systems. 相似文献
54.
K. I. Gnanasekar M. Sharon R. Pinto A. S. Tamhane S. C. Purandare S. P. Pai L. C. Gupta R. Vijayaraghavan 《Zeitschrift für Physik B Condensed Matter》1995,99(2):173-177
Structural and superconducting properties of the system Lu1?x Ca x Ba2 Cu3O7?δ, both in bulk as well as thin film form, have been investigated. Presence of large Ca-ions at the Lu-sites is responsible for phase stability (in 1–2–3 phase) in bulk. In argon annealed tetragonal samples (δ:1) superconductivity is reinstated as in these samples, presence of Ca-ions lead to the generation of holes in the Cu?O planes. In oxygen annealed bulk samples and thin films, there is a large depression ofT c due to divalent Ca-ions present in concentrationx<0.2. Our data indicate that this depression ofT c is likely due to overdoping effect. 相似文献
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58.
The electrical resistivity and Seebeck coefficients of pure MnO single crystals have been measured above the Néel temperature. The material is p type in this temperature range. The results are interpreted on the basis of small-polaron hopping involving charge carriers in one or more sets of transport levels. 相似文献
59.
The online version of the original article can be found at 相似文献
60.
Molar extinction coefficients of some carbohydrates viz. l-arabinose (C5H10O5), d-glucose (C6H12O6), d-mannose (C6H12O6), d-galactose (C6H12O6), d(-) fructose (C6H12O6) and maltose (C12H24O12) in aqueous solutions have been determined at 81, 356, 511, 662, 1173 and 1332 keV by gamma ray transmission method in a
narrow beam good geometry set-up. These coefficients have been found to depend upon the photon energy following a 4-parameter
polynomial. These extinction coefficients for different sugars having the same molecular formula have same values varying
within experimental uncertainty. Within concentration ranges studied, Beer-Lambert law is obeyed very well. 相似文献