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71.
The newton filtration and d-determination of bifurcation problems related to C
0 contact equivalence
In this paper, from the Newton filtration’s point of view, we construct the singular Riemannian metric and use the method in singular theory to study the bifurcation problems, and give the sufficient condition of d-determination of bifurcation problems with respect to C 0 contact equivalence. The special cases of the main result in this paper are the results of Sun Weizhi and Zou Jiancheng. 相似文献
72.
73.
74.
We compute the entropyh
A
(
U
) in the sense of Connes, Narnhofer and Thirring of Bogoliubov automorphisms
U
of the CAR-algebra with respect to invariant quasifree states
A
with 0A1 having pure point spectrum.Supported in part by a grant from the National Science Foundation 相似文献
75.
76.
77.
Superheated water eluent capillary liquid chromatography 总被引:4,自引:0,他引:4
A capillary scale reverse phase liquid chromatography (LC) system using a super hot water eluent is described. The system, constructed in-house from readily available components, has been shown to operate at temperatures as high as 370 °C and pressures in excess of 10 000 psi. The capability of the system is demonstrated with the separation of a mixture of polar and non-polar benzene derivatives on polybutadiene and elemental carbon modified zirconia packings with or without temperature gradients. Six benzene derivatives can be separated in 2 min. 相似文献
78.
One unit of S(IV) (SO2 or SHO3?) is oxidized per 2 units of [NiIII(cyclam)] species to obtain sulfate. Kinetic analyses have been done by varying the acidities (0.013 ? [H+] ? 1.0 M) and halide concentrations (0.000 ? [X?] ? 0.012 M; X=Cl and Br) at constant ionic strength (μ = 1.0 M). The rate law that incorporates the [X?] and [H+] dependence is ?d[NiIII]T/dt=2k[NiIII]T[S(IV)]T where 2k={ka[H+] + kbK + kK′X[H+] [X?] + kK′XK[X?]} {[H+] + K}?1 {1 + K′X[X?]}?1, here ka=87 ± 7 M?1 s?1, kb=(2.5 ± 0.5)×103 M?1 s?1 and pK = 1.8 ± 0.2. Rate constants ka and kb are attributed to the reactions of [NiIII(cyclam) (H2O)2]3+ with SO2 and SHO3?, respectively. Monohalo species apparent equilibrium constants K′Cl=(1600 ± 400) M?1 and K′Br=(190 ± 20) M?1 and rate constants k=80 ± 8 M?1 s?1 and k = 140 ± 15 M?1 s?1 are ascribed to the protonated pathway, involving the [NiIII(cyclam) (H2O)X]2+ and SO2(aq) reaction pairs. The other two rate constants of k=(5 ± 1)×103 M?1 s?1 and k=(3.1 ± 0.5)×104 M?1 s?1, refer to the deprotonated pathway and are assigned to the [NiIII(cyclam) (H2O)X]2+ /SHO3? redox couple. A deuterium H2O / D2O isotope effect of 2.1–2.8 can be attributed partially to an equilibrium isotope effect at low acidity though a small kinetic isotope (2.5 ± 0.5) effect is evident for the dihydrogen sulfito pathway, ka. The kinetic isotope effect and the absence of sulfite radical scavenging effects are explained by a mechanism entailing migration of a hydride from sulfur to the NiIII center to produce a NiIII—H species, which rapidly comproportionates, and S(VI). © 1993 John Wiley & Sons, Inc. 相似文献
79.
Scott Charles D. Woodward Charlene A. Thompson James E. Blankinship Stephen L. 《Applied biochemistry and biotechnology》1990,24(1):799-815
Applied Biochemistry and Biotechnology - Both oxidative and reductive enzymes can be utilized to enhance coal solubilization in aqueous and organic media. Aerobic solubilization was carried out... 相似文献
80.
DongJunWANG QunLUO DanDanJIA XiaoDongLI XinQiouWANG YongHuang ZhenZHEN XinHouLIU 《中国化学快报》2003,14(12):1306-1308
The hydrolysis of tetraethoxysilane (TEOS) occurred on the surface of poly(methyl methacrylate) (PMMA) microshperes immediately after these microshperes were prepared in TEOS. Micron-sized hollow SiO2 spheres were obtained by calcination of the coated PMMA microshperes. It was found that the final hollow spheres were constituted by small SiO2 particles. 相似文献