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81.
Krishnamurthy T Hewel J Bonzagni NJ Dabbs J Bull RL Yates JR 《Rapid communications in mass spectrometry : RCM》2006,20(13):2053-2056
Specific identification of Bacillus anthracis (B. anthracis) is vital for the accurate treatment of afflicted personnel during biological warfare situations and civilian terrorist attacks. In order to accomplish this, we have subjected the lysates from B. anthracis to affinity purification using monoclonal antibodies for the selected antigenic protein present in the bacteria. The bound antigenic protein was identified by multi-dimensional protein identification technology (MudPIT) to be a surface layer protein EA1. The same antigen was identified from the lysates from a few strains of B. anthracis demonstrating the observation to be common for B. anthracis strains. Hence, this presents an effective pathway for the identification of the bacteria present in unknown samples of various origins. Generation of a database containing the EA1 protein has been found to be useful in the database search of unknown samples. 相似文献
82.
83.
84.
Krishnamurthy V. V. Watanabe I. Nagamine K. Kitagawa J. Ishikawa M. Komatsubara T. 《Hyperfine Interactions》2001,136(3-8):385-389
Magnetic and quadrupolar ordering phenomena in a Ce3Pd20Ge6 single crystal have been investigated by muon spin rotation/relaxation (μ+SR) spectroscopy. We have observed spontaneous precession of muons in zero-field below T
N
=0.7 K in the antiferromagnetic state. The precession frequency follows the power law: ν(T)=ν(0)(1−T/T
N
)
n
. The exponent n=0.43(2) is close to the mean-field value of 0.5. The muon longitudinal spin relaxation rate 1/T
1 is found to be nearly independent of temperature in the range of 0.3 to 2 K, i.e., across either T
N
or T
Q
=1.2 K, the quadrupolar ordering temperature. Two likely mechanisms for the temperature independent behavior of 1/T
1 are suggested.
This revised version was published online in September 2006 with corrections to the Cover Date. 相似文献
85.
H. D. Sherali R. S. Krishnamurthy F. A. Al-Khayyal 《Journal of Optimization Theory and Applications》1996,90(1):183-201
In this paper, we develop an enhanced intersection cutting-plane algorithm for solving a mixed integer 0–1 bilinear programming formulation of the linear complementarity problem (LCP). The matrixM associated with the LCP is not assumed to possess any special structure, except that the corresponding feasible region is assumed to be bounded. A procedure is described to generate cuts that are deeper versions of the Tuy intersection cuts, based on a relaxation of the usual polar set. The proposed algorithm then attempts to find an LCP solution in the process of generating either a single or a pair of such strengthened intersection cuts. The process of generating these cuts involves a vertexranking scheme that either finds an LCP solution, or else these cuts eliminate the entire feasible region leading to the conclusion that no LCP solution exists. Computational experience on various test problems is provided.This material is based upon work supported by the National Science Foundation under Grant No. DMII-9121419 to the first author and Grant No. DMII-9114489 to the third author. The authors gratefully acknowledge the constructive suggestions of a referee that helped focus the approach and its presentation. 相似文献
86.
Fork/join stations are commonly used to model the synchronization constraints in queuing models of computer networks, fabrication/assembly systems and material control strategies for manufacturing systems. This paper presents an exact analysis of a fork/join station in a closed queuing network with inputs from servers with two-phase Coxian service distributions, which models a wide range of variability in the input processes. The underlying queue length and departure processes are analyzed to determine performance measures such as throughput, distributions of the queue length and inter-departure times from the fork/join station. The results show that, for certain parameter settings, variability in the arrival processes has a significant impact on system performance. The model is also used to study the sensitivity of performance measures such as throughput, mean queue lengths, and variability of inter-departure times for a wide range of input parameters and network populations. 相似文献
87.
George A. Olah Maurice Stephenson Joe G. Shih V. V. Krishnamurthy G. K. Surya Prakash 《Journal of fluorine chemistry》1988,40(2-3)
One bond 13C-19F coupling constant is used as a criterion to measure the extent of fluorine non-bonded electron pair back-donation to a carbenium center in a series of α-fluorodiarylcarbenium ions
. The electron demand at the cationic center was probed by systematically changing the nature of substituents on the phenyl rings, applying the tool of increasing electron demand to the study. 相似文献
88.
Utilizing a new complex-band-structure technique, the electronic structure of model Si-Si1?xGex and MOS superlattices have been obtained over a wide range of layer thickness d (11 ≤ d ≤ 110 A). For d ≥ 44 A, it is found that these systems exhibit a direct fundamental band gap. Further calculations of band-edge effective masses and impurity scattering rates suggest the possibility of a band-structure-driven enhancement in electron mobility over bulk silicon. 相似文献
89.
90.
The Rayleigh-Taylor (RT) instability at the interface between fluid and fluid saturated sparsely packed porous medium has been investigated making use of boundary layer approximation and Saffmann [8] boundary condition. An analytical solution for dispersion relation is obtained and is numerically evaluated for different values of the parameters. It is shown that RT instability can be controlled by a suitable choice of the thickness of porous layer, ratio of viscosities and the slip parameter. 相似文献