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81.
Rodney Nillsen 《Elemente der Mathematik》2001,56(3):105-121
82.
83.
84.
Rodney A. Bryant 《Proceedings of the Combustion Institute》2011,33(2):2481-2487
Stereoscopic particle image velocimetry (SPIV) was applied to a fire-induced doorway flow to provide the velocity field for computations of the mass flow rate of air into an enclosure. For a flow of uniform temperature and concentration, the technique met all of the requirements to provide the best estimate of the mass flow rate. Simultaneous measurements of vertical distributions of velocity and temperature were also conducted with conventional vent flow techniques, bi-directional probes and thermocouples. Correction factors for mass flow rate computations using the conventional techniques were determined based on comparisons to the SPIV results. An average correction factor of unity was determined for the bi-directional probe technique thus further confirming the utilization of velocity distributions acquired using the technique in mass flow rate computations. An average correction factor of 0.69 was determined for mass flow rates computed from vertical temperature distributions inside and outside the enclosure. This agrees with average correction factors determined in previous studies. The results from the present study suggest that the conventional techniques, which are practical and affordable for routine fire testing, may be applied with greater confidence for fires up to 500 kW. 相似文献
85.
86.
Rodney Y. Sharp 《Proceedings of the American Mathematical Society》2007,135(3):665-670
Let be a commutative Noetherian local ring of prime characteristic. The purpose of this paper is to provide a short proof of G. Lyubeznik's extension of a result of R. Hartshorne and R. Speiser about a module over the skew polynomial ring (associated to and the Frobenius homomorphism , in the indeterminate ) that is both -torsion and Artinian over .
87.
Bruce S. Dien Nick Nagle Kevin B. Hicks Vijay Singh Robert A. Moreau Melvin P. Tucker Nancy N. Nichols David B. Johnston Michael A. Cotta Quang Nguyen Rodney J. Bothast 《Applied biochemistry and biotechnology》2004,115(1-3):937-949
Approximately 9% of the 9.7 billion bushels of corn harvested in the United States was used for fuel ethanol production in 2002, half of which was prepared for fermentation by dry grinding. The University of Illinois has developed a modified dry grind process that allows recovery of the fiber fractions prior to fermentation. We report here on conversion of this fiber (Quick Fiber [QF]) to ethanol. QF was analyzed and found to contain 32%wt glucans and 65%wt total carbohydrates. QF was pretreated with dilute acid and converted into ethanol using either ethanologenic Escherichia coli strain FBR5 or Saccharomyces cerevisiae. For the bacterial fermentation the liquid fraction was fermented, and for the yeast fermentation both liquid and solids were fermented. For the bacterial fermentation, the final ethanol concentration was 30 g/L, a yield of 0.44 g ethanol/g of sugar(s) initially present in the hydrolysate, which is 85% of the theoretical yield. The ethanol yield with yeast was 0.096 gal/bu of processed corn assuming a QF yield of 3.04 lb/bu. The residuals from the fermentations were also evaluated as a source of corn fiber oil, which has value as a nutraceutical. Corn fiber oil yields were 8.28%wt for solids recovered following prtetreatment. 相似文献
88.
Maria G. Miranda Elizabeth J. Norton Rodney P. Feazell Kevin K. Klausmeyer Kevin G. Pinney 《Journal of chemical crystallography》2006,36(5):309-314
The title compounds, (Z)-1-[(2′,4′-dimethoxy-3′-nitro)-phenyl]-2-[(3″,4″,5″-trimethoxy)-phenyl]ethene, C19H21O7N (I), and 2-amino-4-methyl-6-(3,4,5-trimethoxy-phenyl)-pyrimidine, C14H17O3N3 (II), were obtained unexpectedly from a reaction involving (Z)-1-[(2′,3′-dinitro-4′-methoxy)-phenyl]-2-[(3″,4″,5″-trimethoxy)-phenyl]ethene (IV). The molecular structures of these compounds were obtained by single-crystal X-ray diffraction. Crystallization of I occurs in the centrosymmetric monoclinic space group P21/c (No. 14) with a=7.7311(5), b=19.9239(13), c=11.5725(8); and β=92.193(3) and Z=4. Crystallization of II occurs in the centrosymmetric monoclinic space group C2/c (No. 15) with a=21.296(2), b=6.8963(7), c=20.001(2); and β=114.121(6) and Z=8. Details of the synthesis and the structural characterization of the title compounds are presented and discussed. 相似文献
89.
Summary In this paper we study the Dirichlet problem for the minimal surface equation in a open set Ω without any assumption about
the regularity of ϖΩ. We prove an existence theorem using only the pseudoconvexity of Ω.
Riassunto In questo lavoro studiamo il problema di Dirichlet per l'equazione delle superfici minime in un aperto Ω diR n sulla cui frontiera non si fa nessuna ipotesi di regolarità. Si ottiene un teorema di esistenza usando la sola pseudoconvessità di Ω.相似文献
90.
Rodney T. Hansen 《International Journal of Mathematical Education in Science & Technology》2013,44(4):535-536
The multinomial theorem and a basic property of multinomial coefficients yield a way of counting the number of chains of coloured beads of a fixed length where each colour can be used repeatedly. This coupled with a simple counting argument forms a concise proof of Fermat's theorem. 相似文献