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101.
The Multiple Semi‐coarsened Grid (MSG) multigrid method of Mulder (J. Comput. Phys. 1989; 83 :303–323) is developed as a solver for fully implicit discretizations of the time‐dependent incompressible Navier–Stokes equations. The method is combined with the Symmetric Coupled Gauss–Seidel (SCGS) smoother of Vanka (Comput. Methods Appl. Mech. Eng. 1986; 55 :321–338) and its robustness demonstrated by performing a number of large‐eddy simulations, including bypass transition on a flat plate and the turbulent thermally‐driven cavity flow. The method is consistently able to reduce the non‐linear residual by 5 orders of magnitude in 40–80 work units for problems with significant and varying coefficient anisotropy. Some discussion of the parallel implementation of the method is also included. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
102.
P.B. Vold J.O. Andreassen J.R. Lien A. Graue E.R. Cosman W. Dünnweber D. Schmitt F. Nüsslin 《Nuclear Physics A》1973,215(1):61-78
The reaction 207Pb(d, p)208Pb has been studied at Ed = 18.0 MeV using the MPI Heidelberg Emperor tandem accelerator and multiple-gap spectrograph. The average resolution of 18 keV was better than previous measurements, and this, combined with the long beam exposure, allowed many finer details of the neutron particle-hole structure of 208Pb to be examined. In all, 45 levels were seen up to Ex = 6.3 MeV, many of which had never been seen before. A DWBA analysis of the stripping transitions angular distributions is made, and values of (2J + 1)Sij, energy centroids, and summed strengths are given. An interesting cluster of 1i and 2g levels at Ex ≈ 4.2 MeV are resolved and are compared to recent isobaric analog state data. A search for weak stripping strength to known pairing vibrations in 208Pb gave essentially negative results and points to the need for improved ultra-resolution measurements. 相似文献
103.
Energy levels in 42Ca up to 7.8 MeV have been studied in the neutron capture reaction 41Ca(d, p)42Ca with 12 MeV bombarding energy. Ninety-four excited states have been identified and angular distributions have been measured in the interval from 5° to 110° by means of a broad-range magnetic spectrograph. The angular distributions together with DW calculations have been used to determine In values and spectroscopic factors. The strength sum agrees with shell-model expectations if the f spectroscopic factors are renormalized by , in line with other . transfer experiments on 40Ca and 41Ca. A similar renormalization of the ln = 1 spectroscopic factors brings this strength sum in accordance with the shell-model calculations. The effective () matrix elements for 42Ca are compared with the corresponding matrix elements of 42Sc and 48Sc. The differences between the three sets of matrix elements are of the order of a few hundred keV or less. The monopole centroid energy of the ( multiplet is shifted downwards in the mass-42 nuclei compared to 48Sc, possibly indicating the importance of the monopole pairing force near 40Ca. 相似文献
104.
B.B. Back J. Bang S. Bjørnholm J. Hattula P. Kleinheinz J.R. Lien 《Nuclear Physics A》1974,222(2):377-387
The coupling of the single particle motion of the neutron to other degrees of freedom is studied by the (d, p) reaction leading to highly excited states in rare earth nuclei. Experimental spectra have been obtained with a telescope counter system for 13 rare earth isotopes of Gd, Dy, Er and Yb. The results are compared with calculations based upon the single particle model in a deformed Saxon-Woods potential. The spreading of the single particle strength resulting from the coupling to other degrees of freedom is taken into account in a simple phenomenological way. A qualitative similarity between the experimental and calculated spectra is observed, and the total integrated (d, p) cross section up to the neutron binding energy is reproduced quite closely by the calculations. For a given excitation energy, the amount of structure in the experimental spectrum seems to decrease with neutron number for each element investigated. 相似文献
105.
A p‐list assignment L of a graph G assigns to each vertex v of G a set of permissible colors. We say G is L‐(P, q)‐colorable if G has a (P, q)‐coloring h such that h(v) ? L(v) for each vertex v. The circular list chromatic number of a graph G is the infimum of those real numbers t for which the following holds: For any P, q, for any P‐list assignment L with , G is L‐(P, q)‐colorable. We prove that if G has an orientation D which has no odd directed cycles, and L is a P‐list assignment of G such that for each vertex v, , then G is L‐(P, q)‐colorable. This implies that if G is a bipartite graph, then , where is the maximum average degree of a subgraph of G. We further prove that if G is a connected bipartite graph which is not a tree, then . © 2008 Wiley Periodicals, Inc. J Graph Theory 59: 190–204, 2008 相似文献
106.
An enzymatic membrane reactor (EMR) for enantioseparation of (R,S)-ketoprofen via Candida antarctica lipase B (CALB) as biocatalyst was investigated. A comparative study of free and immobilized CALB was further conducted. The catalytic behaviour of CALB in an EMR was affected by the process parameters of enzyme load, substrate concentration, substrate molar ratio, lipase solution pH, reaction temperature, and substrate flow rate. Immobilization of CALB in the EMR was able to reduce the amount of enzyme required for the enantioseparation of (R,S)-ketoprofen. Immobilized CALB in the EMR assured higher reaction capacity, better thermal stability, and reusability. It was also found to be more cost effective and practical than free CALB in a batch reactor. 相似文献
107.
This study was conducted to better understand the influences exerted by seven Taiwan‐produced adulterants on the forensic gas chromatographic‐mass spectrometric (GC‐MS) confirmatory urinalysis of amphetamines. The results verified that, when added at 5‐15% (w/w), chlorine bleach would lower the GC‐MS outcomes of the spiked and case specimens by 36‐63%, and was most likely to cause false negatives. Liquid soap, potassium dichromate, soda water for drinking, and tap water would decrease the GC‐MS outcomes by 9‐29%, 8‐20%, 8‐20%, and 5‐16%, respectively, and also had the risk of negating near‐cutoff initial positives into false confirmatory negatives. The negative‐directing effects were mostly due to degradation of analytes and/or deactivation of the derivatizing agent by oxidizing adulterants and/or dilution of analytes by the added liquid. Alum and table salt added as powder had little impact on the test. Responsible institutions and relevant laboratories should face the facts seriously and include the specimen validity testing (SVT) battery in the routine drug testing procedures. 相似文献
108.
Jin‐Cherng Lien Yu‐Dong Jiang Chun‐Jen Chen Sheng‐Chu Kuo Li‐Jiau Huang 《中国化学会会志》2008,55(5):1160-1165
In continuing search for novel cell differentiation agents, a series of derivatives of indole‐3‐acetic acid and indole‐3‐carboxylic acid were prepared and tested against HL‐60 cells for their differentiation and antiproliferation activities. Among them, N‐ethyl‐1‐benzylindole‐3‐carboxamide ( 14 ) was the most potent, whereas N‐methyl 1‐benzylindole‐3‐acetamide ( 5 ) and N‐methyl 1‐benzylindole‐3‐carboxamide ( 13 ) synergistically potentiated with all‐trans‐retinoic acid to induce cell differentiation as well as antiproliferation. Our results indicate that these compounds are effective cell differentiation and antiproliferation agents in combination with retinoic acid. 相似文献
109.
Multiple linear regression analysis was used to deduce the correlation between the monosaccharide composition ratios of 10 regionally different strains of Lentinula edodes and their in vitro macrophage stimulatory activities. Arabinose, xylose, mannose and galactose were identified as the monosaccharides that could be related to macrophage stimulatory activities. Additional principal component analysis and factor analysis methods were used to treat the same monosaccharide composition ratio data and the compositions of arabinose, xylose, mannose and galactose were found to be important. Interestingly, glucose, although presented in large compositions in all strains presumably forms the backbone of the polysaccharide structures, is not selected as the determinant factor for either structural characteristics or that of the in vitro macrophage stimulatory activities. 相似文献
110.
Email: chlien{at}mail.nkmu.edu.tw
Received on August 10, 2006; Accepted on September 6, 2006 In this paper, delay-dependent guaranteed cost observer-basedcontrol for neutral systems with time-varying delays is considered.Control and observer gains will be given from the linear matrixinequality feasible solutions. Optimal guaranteed cost observer-basedcontrol which will minimize the guaranteed cost of the systemis provided. 相似文献