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931.
Vandana Tripathi Lagy T Baby PV Madhusudhana Rao SK Hui R Singh JJ Das P Sugathan N Madhavan AK Sinha 《Pramana》1999,53(3):535-539
The ground state and excited state transfer yields for the 2-neutron pickup channel in the 28Si+68Zn system have been measured explicitly. The recoil mass separator at the nuclear Science Centre, New Delhi was used for the
measurement. A NaI(T1) detector was used for detecting the deexcitation γ’s from the transfer products. The kinematic coincidence technique was employed for the transfer measurement. Simplified coupled
channels calculations show that out of all transfer channels the major contribution to the sub-barrier enhancement comes from
the ground state 2 neutron pickup channel with a ground state Q-value of+1.83 MeV. 相似文献
932.
In this paper we investigate the role of domain representability and Scott-domain representability in the class of Moore spaces and the larger class of spaces with a base of countable order. We show, for example, that in a Moore space, the following are equivalent: domain representability; subcompactness; the existence of a winning strategy for player α (= the nonempty player) in the strong Choquet game Ch(X); the existence of a stationary winning strategy for player α in Ch(X); and Rudin completeness. We note that a metacompact ?ech-complete Moore space described by Tall is not Scott-domain representable and also give an example of ?ech-complete separable Moore space that is not co-compact and hence not Scott-domain representable. We conclude with a list of open questions. 相似文献
933.
A computational procedure is presented for solving complex variably saturated flows in porous media, that may easily be implemented into existing conventional finite‐volume‐based computational fluid dynamics codes, so that their functionality might be geared upon to readily enable the modelling of a complex suite of interacting fluid, thermal and chemical reaction process physics. This procedure has been integrated within a multi‐physics finite volume unstructured mesh framework, allowing arbitrarily complex three‐dimensional geometries to be modelled. The model is particularly targeted at ore heap‐leaching processes, which encounter complex flow problems, such as infiltration into dry soil, drainage, perched water tables and flow through heterogeneous materials, but is equally applicable to any process involving flow through porous media, such as in environmental recovery processes. The computational procedure is based on the mixed form of the classical Richards equation, employing an adaptive transformed mixed algorithm that is numerically robust and significantly reduces compute (or CPU) time. The computational procedure is accurate (compares well with other methods and analytical data), comprehensive (representing any kind of porous flow model), and is computationally efficient. As such, this procedure provides a suitable basis for the implementation of large‐scale industrial heap‐leach models. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
934.
Bennett F. Davenport S. J. Speak G. W. Slatter und T. H. Easterfield 《Fresenius' Journal of Analytical Chemistry》1890,29(1):320
Ohne Zusammenfassung 相似文献
935.
936.
B.C. Connelly B.A.V. Bennett M.D. Smooke M.B. Long 《Proceedings of the Combustion Institute》2009,32(1):879-886
A different approach to comparing experimental data and numerical simulation data is presented. Traditionally, when making comparisons with simulations, experimentalists have sought to measure the same fundamental quantities (e.g., mole fractions) that are output by numerical simulations. This approach often requires measurement of many variables to arrive at the desired quantity, and uncertainty may accumulate with each additional measurement. Because recent advances in computational resources have led to more detailed numerical models, more complete information is available within simulations. This allows for the possibility of using simulation results to derive predictions of measured signals (i.e., “computed signals”) rather than measuring many quantities to derive a single fundamental quantity. Three examples of comparing measured and computed signals are presented: NO laser-induced fluorescence (LIF) images in both non-sooting and sooting diffusion flames, and luminosity images of sooting diffusion flames. For illustration, the non-sooting LIF data is treated both by the traditional method of comparing fundamental quantities and by comparing measured and computed signals. In each example, the comparison of measured and computed signals yields quantitative information similar to that obtainable through comparison of traditional quantities, along with reduced noise in the experimental data. 相似文献
937.
It was shown by Gerhard Ringel that one of the three non-isomorphic Steiner triple systems of order 15 having an automorphism
of order 5 may be bi-embedded as the faces of a face 2-colourable triangular embedding of K
15 in a suitable orientable surface. Ringel's bi-embedding was obtained from an appropriate current graph. In a recent paper,
the present authors showed that a second STS(15) of this type may also be bi-embedded. In the present paper we show that this
second bi-embedding may also be obtained from a current graph. Furthermore, we exhibit a third current graph which yields
a bi-embedding of the third STS(15) of this type.
Received: October 5, 1998 相似文献
938.
Saleta Vazquez‐Rodriguez Miranda Wright Catherine M. Rogers Adam P. Cribbs Srikannathasan Velupillai Martin Philpott Henry Lee James E. Dunford Kilian V. M. Huber Matthew B. Robers James D. Vasta Marie‐Laetitia Thezenas Sarah Bonham Benedikt Kessler James Bennett Oleg Fedorov Florence Raynaud Adam Donovan Julian Blagg Vassilios Bavetsias Udo Oppermann Chas Bountra Akane Kawamura Paul E. Brennan 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(2):525-529
939.
Bennett Kevin T. Kozimor Stosh A. Manard Benjamin T. Mocko Veronika Pacheco Susan D. Schake Ann R. Wu Ruilian Olson Angela C. 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(2):281-289
A rapid method for the separation and qualitative analysis of several neutron activation products (198Au, 192Ir, 72Ga, 51Cr, 191/195m/197Pt, 54Mn, 57Co, and 59Fe) from fission products and soil matrixes has been developed. Analytes were isolated within 20 h using ion exchange chromatography. After separation, the activation products were characterized by γ-spectroscopy and inductively coupled plasma-optical emission spectroscopy. Validation experiments demonstrated versatility of the method, showing that the activation products could be isolated from fresh fission products and other contaminants associated with complex soil matrixes.
相似文献940.
Matthews ML Periyannan G Hajdin C Sidgel TK Bennett B Crowder MW 《Journal of the American Chemical Society》2006,128(40):13050-13051
In an effort to probe the reaction mechanism of VanX, the d-ala-d-ala dipeptidase required for high-level vancomycin resistance in bacteria, stopped-flow kinetic and rapid-freeze quench EPR studies were conducted on the Co(II)-substituted enzyme when reacted with d-ala-d-ala. The intensity of the Co(II) ligand field band at 550 nm decreased (epsilon550 = 140 to 18 M-1 cm-1) when VanX was reacted with substrate, suggesting that the coordination number of the metal increases from 5 to 6 upon substrate binding. The stopped-flow trace was fitted to a kinetic mechanism that suggests the presence of an intermediate whose breakdown is rate-limiting. Rapid-freeze quench EPR studies verified the presence of a reaction intermediate that exhibits an unusually low hyperfine constant (33 G), which suggests a bidentate coordination of the intermediate to the metal center. The EPR studies also identified a distinct enzyme product complex. The results were used to offer a detailed reaction mechanism for VanX that can be used to guide future inhibitor design efforts. 相似文献