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51.
Donald C. Berndt Jill E. Angus Michael J. Wood Richard F. Atkinson Tanveer A. Qureshi Brian J. Shay Aura I. Provancher 《国际化学动力学杂志》1989,21(6):431-437
Rates of reaction for the alkaline hydrolysis of various hydroxamic acids in the presence of cetyltrimethylammonium bromide have been determined. Empirical reaction orders of zero, one-half, and one were found for the hydroxamic acids depending upon reaction conditions and substrate structure. N -methylhydroxamic acids exhibited only first-order kinetics. The results are consistent with the Michaelis-Menten rate equation. 相似文献
52.
We demonstrate the existence of a new steady-state magnetic reconnection configuration which lies at the boundary of the basins of attraction between the Sweet-Parker and Hall reconnection configurations. The solution is linearly unstable to small perturbations and its identification required a novel iterative numerical technique. The eigenmodes of the unstable solution are localized near the X line, suggesting that the onset of fast reconnection in a weakly collisional plasma is initiated locally at the X line as opposed to remotely at the boundaries. 相似文献
53.
K. J. Bachmann E. Buehler J. L. Shay A. R. Strnad 《Journal of Electronic Materials》1975,4(2):389-406
The growth of bulk indium phosphide crystals via liquid encapsulated Czochralski pulling from both stoichiometric and nonstoichiometric
melts is described. Nominally un-doped crystals with carrier concentration ND-NA = 6 × 1015 cm−3 and Hall mobilities of 4510 cm2/Vsec at room temperature were grown. Also, we prepared Zn-or Cd-doped p-type crystals in the range 1016 ≤ NA-ND ≤ 1018 cm−3 with Hall mobilities ≤ 130 cm2/Vsec and Sn-doped n-type crystals in the range 4 × 1017 ≤ NA-ND ≤ 1018 cm-3 with Hall mobilities ≤ 2400 cm2/Vsec. The dislocation density of LEC pulled InP crystals is typically ~ 104 cm−2. 相似文献
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We show that for every n-point metric space M and positive integer k, there exists a spanning tree T with unweighted diameter O(k) and weight w(T)=O(k⋅n 1/k )⋅w(MST(M)), and a spanning tree T′ with weight w(T′)=O(k)⋅w(MST(M)) and unweighted diameter O(k⋅n 1/k ). These trees also achieve an optimal maximum degree. Furthermore, we demonstrate that these trees can be constructed efficiently. 相似文献
57.
IS Dubinsky-Davidchik S Potash I Goldberg A Vigalok AN Vedernikov 《Journal of the American Chemical Society》2012,134(34):14027-14032
A series of diphosphine Pt(II) aryl iodo complexes were reacted with XeF(2) to cleanly produce the corresponding Pt(II) difluoro complexes and free iodoarenes. However, when aryl ligands bearing fluoro substituents in the ortho positions were used, the formation of the corresponding Pt(II) aryl fluoro complexes was observed in the reaction with XeF(2). In the case of the Pt-C(6)F(5) complex, the products of the fluoride-for-iodide exchange were the only products observed by means of (31)P and (19)F NMR spectroscopy. The experimental and theoretical studies suggest that the formation of iodine-fluorine bond may accompany this transformation. The plausible "I-F" species could be trapped by electron-richer organoplatinum complexes to give a Pt(IV) transient which subsequently eliminates the corresponding aryl iodide. Hence, in some cases a pathway involving an attack of XeF(2) at the iodo ligand of Pt(II) aryl iodo complexes to generate I-F species can be operative in addition to or instead of the XeF(2) attack at the metal center. Our DFT studies demonstrate that the electrophilic attacks of XeF(2) at both sites, platinum and iodide, can be competitive. 相似文献
58.
The propagation of reconnection signatures and their associated energy are examined using kinetic particle-in-cell simulations and Cluster satellite observations. It is found that the quadrupolar out-of-plane magnetic field near the separatrices is associated with a kinetic Alfvén wave. For magnetotail parameters, the parallel propagation of this wave is super-Alfvénic (V(∥) ~ 1500-5500 km/s) and generates substantial Poynting flux (S ~ 10(-5)-10(-4) W/m(2)) consistent with Cluster observations of magnetic reconnection. This Poynting flux substantially exceeds that due to frozen-in ion bulk outflows and is sufficient to generate white light aurora in Earth's ionosphere. 相似文献
59.
Shay Mailloux Nataliia Guz Maria Gamella Carballo José M. Pingarrón Evgeny Katz 《Analytical and bioanalytical chemistry》2014,406(20):4825-4829
A new sense-and-act system was realized by integrating a biocatalytic/bioaffinity electrode responding to immune signals represented by an antibody and a polymer-modified electrode loaded with drug-mimicking species. The release of the drug-mimicking species was achieved specifically in response to a signal antibody, thus demonstrating for the first time an immune-induced drug-releasing process. The present approach promises new options for future applications in controlled drug release and personalized medicine. Figure
Electrochemical immune-sensing system was integrated with the substance-releasing modified electrode to demonstrate the immune-triggered drug release process 相似文献
60.