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991.
B. C. Chanyal P. S. Bisht Tianjun Li O. P. S. Negi 《International Journal of Theoretical Physics》2012,51(11):3410-3422
Starting with the usual definitions of octonions, an attempt has been made to establish the relations between octonion basis elements and Gell-Mann λ matrices of SU(3) symmetry on comparing the multiplication tables for Gell-Mann λ matrices of SU(3) symmetry and octonion basis elements. Consequently, the quantum chromo dynamics (QCD) has been reformulated and it is shown that the theory of strong interactions could be explained better in terms of non-associative octonion algebra. Further, the octonion automorphism group SU(3) has been suitably handled with split basis of octonion algebra showing that the SU(3) C gauge theory of colored quarks carries two real gauge fields which are responsible for the existence of two gauge potentials respectively associated with electric charge and magnetic monopole and supports well the idea that the colored quarks are dyons. 相似文献
992.
Yan?ZhaoEmail author Yan-Lin?Liao Ping?Lou 《International Journal of Theoretical Physics》2012,51(7):2109-2112
We propose a concentration scheme of the W class state via cavity QED technique. In our scheme the influences of cavity decay and atomic spontaneous emission have been considered. Furthermore, the atomic spontaneous emission has been suppressed by using non-radiative transitions in atoms with three-level structure, and the photonic qubit is used as flying qubit and atomic qubit as stationary qubit. Therefore our scheme is comparatively easy to realize within techniques presently available. 相似文献
993.
A. S. Rawat Seema Rawat Tianjun Li O. P. S. Negi 《International Journal of Theoretical Physics》2012,51(10):3274-3289
The quaternion Dirac equation in presence of generalized electromagnetic field has been discussed in terms of two gauge potentials of dyons. Accordingly, the supersymmetry has been established consistently and thereafter the one, two and component Dirac Spinors of generalized quaternion Dirac equation of dyons for various energy and spin values are obtained for different cases in order to understand the duality invariance between the electric and magnetic constituents of dyons. 相似文献
994.
Varnum SM Warner MG Dockendorff B Anheier NC Lou J Marks JD Smith LA Feldhaus MJ Grate JW Bruckner-Lea CJ 《Analytica chimica acta》2006,570(2):137-143
Two immunoassay platforms were developed for either the sensitive or rapid detection of botulinum neurotoxin A (BoNT/A), using high-affinity recombinant monoclonal antibodies against the receptor binding domain of the heavy chain of BoNT/A. These antibodies also bind the same epitopes of the receptor binding domain present on a nontoxic recombinant heavy chain fragment used for assay development and testing in the current study. An enzyme-linked immunosorbent assay (ELISA) microarray using tyramide amplification for localized labeling was developed for the specific and sensitive detection of BoNT. This assay has the sensitivity to detect BoNT in buffer and blood plasma samples down to 14 fM (1.4 pg mL−1). Three capture antibodies and one antibody combination were compared in the development of this assay. Using a selected pair from the same set of recombinant monoclonal antibodies, a renewable surface microcolumn sensor was developed for the rapid detection of BoNT/A in an automated fluidic system. The ELISA microarray assay, because of its sensitivity, offers a screening test with detection limits comparable to the mouse bioassay, with results available in hours instead of days. The renewable surface assay is less sensitive but much faster, providing results in less than 10 min. 相似文献
995.
A large domain motion in adenylate kinase from E. coli (AKE) is studied with molecular dynamics. AKE undergoes a large-scale rearrangement of its lid and AMP-binding domains when the open form closes over its substrates, AMP, and Mg2+-ATP, whereby the AMP-binding and lid domains come closer to the core. The third domain, the core, is relatively stable during this motion. A reaction coordinate that monitors the distance between the AMP-binding and core domains is selected to be able to compare with the results of energy transfer experiments. Sampling along this reaction coordinate is carried out by using a distance replica exchange method (DREM), where systems that differ by a restraint potential enforcing different reaction coordinate values are independently simulated with periodic attempts at exchange of these systems. Several methods are used to study the efficiency and convergence properties of the DREM simulation and compared with an analogous non-DREM simulation. The DREM greatly accelerates the rate and extent of configurational sampling and leads to equilibrium sampling as measured by monitoring collective modes obtained from a principal coordinate analysis. The potential of mean force along the reaction coordinate reveals a rather flat region for distances from the open to a relatively closed AKE conformation. The potential of mean force for smaller distances has a distinct minimum that is quite close to that found in the closed form X-ray structure. In concert with a decrease in the reaction coordinate distance (AMP-binding-to-core distance) the lid-to-core distance of AKE also decreases. Therefore, apo AKE can fluctuate from its open form to conformations that are quite similar to its closed form X-ray structure, even in the absence of its substrates. 相似文献
996.
997.
998.
设计了一种离轴双反馈外腔能够有效地改善激光二极管阵列的线宽和光束质量。闪耀光栅和高反镜之间形成了一个共振腔。通过调整光栅和高反镜之间的倾角可以选定一个空间模在共振腔中放大。将一个半波片插入外腔中的光栅反馈支路,来控制反馈光的数量,激光从光栅反馈支路输出。运用这项技术,在工作电流16 A,可以把激光二极管阵列的输出线宽压缩到0.15 nm,光束束宽积减小到283 mm.mrad。由于光栅的锁定作用,中心波长几乎不随温度的变化而改变。在工作电流17A时,输出激光的功率为2.44 W,斜率效率为0.5 W/A。 相似文献
999.
Xin Gao Zhaofeng Kang Tianjun Li 《The European Physical Journal C - Particles and Fields》2010,69(3-4):467-480
We propose two supersymmetric Standard Models (SMs) with decaying and stable dark matter (DM) particles. To explain the SM fermion masses and mixings and have a heavy decay DM particle S, we consider the Froggatt–Nielsen mechanism by introducing an anomalous U(1) X gauge symmetry. Around the string scale, the U(1) X gauge symmetry is broken down to a Z 2 symmetry under which S is odd while all the SM particles are even. S obtains a vacuum expectation value around the TeV scale, and then it can three-body decay dominantly to the second/third family of the SM leptons in Model I and to the first family of the SM leptons in Model II. Choosing a benchmark point in the constrained minimal supersymmetric SM with exact R parity, we show that the lightest neutralino DM is consistent with the CDMS II experiment. Considering S three-body decay and choosing suitable parameters, we show that the PAMELA and Fermi-LAT experiments and the PAMELA and ATIC experiments can be explained in Model I and Model II, respectively. 相似文献
1000.
An original design of ring-core photonic crystal fiber (RPCF) is proposed. By splicing a section of the homemade RPCF between two segments of single mode fibers (SMFs), a simple modal interferometer is presented and experimentally demonstrated. Owing to the effects of the collapsed region, the ring modes in RPCF can be effectively activated. To our knowledge, it is the first time to demonstrate the modal interferometer based on the interference between the ring modes, which is different from the previously reported interferometers based on the interference between core modes or cladding modes. The temperature and strain characteristics of the interferometers with different lengths of RPCF are investigated. 相似文献