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941.
The dynamics of triple-well trapped Bose-Einstein condensates with atoms feeding and loss effects 下载免费PDF全文
In this paper, we consider the macroscopic quantum tunnelling and self-trapping phenomena of Bose-Einstein condensates (BECs) with three-body recombination losses and atoms feeding from thermal cloud in triple-well potential. Using the three-mode approximation, three coupled Gross-Pitaevskii equations (GPEs), which describe the dynamics of the system, are obtained. The corresponding numerical results reveal some interesting characteristics of BECs for different scattering lengths. The self-trapping and quantum tunnelling both are found in zero-phase and :r-phase modes. Furthermore, we observe the quantum beating phenomenon and the resonance character during the self-trapping and quantum tunnelling. It is also shown that the initial phase has a significant effect on the dynamics of the system. 相似文献
942.
对作者所提出的无干涉条纹直接电场重构测量飞秒脉冲的振幅和相位的新方法作出进一步理论分析,并通过实验测量说明该方法的优越性.该方法克服了传统的SPIDER方法的弊病,能得到一组无干涉条纹的图像,排除传统方法必须使用傅里叶变换滤波消除干涉条纹而引进的系统误差,使得该方法能够采用较简便设备且能较准确测量飞秒脉冲强度轮廓和相位.最后给出同一条件下新方法和传统SPIDER方法分别重构的脉冲强度自相关曲线与实验测量结果的比较,以说明新方法的有效性和优越性. 相似文献
943.
Based on the property analysis of interferential multispectral images, a novel compression algorithm of partial set partitioning in hierarchical trees (SPIHT) with classified weighted rate-distortion optimization is presented.After wavelet decomposition, partial SPIHT is applied to each zero tree independently by adaptively selecting one of three coding modes according to the probability of the significant coefficients in each bitplane.Meanwhile the interferential multispectral image is partitioned into two kinds of regions in terms of luminous intensity, and the rate-distortion slopes of zero trees are then lifted with classified weights according to their distortion contribution to the constructed spectrum.Finally a global ratedistortion optimization truncation is performed.Compared with the conventional methods, the proposed algorithm not only improves the performance in spatial domain but also reduces the distortion in spectral domain. 相似文献
944.
ZHANG Zhen-Xia LIU Hong-Bang WU Ning YU Guo-Wei SHEN Xiao-Yan ZHENG Han-Qing 《中国物理C(英文版)》2008,32(11)
The J/ψ hadronic decays provide good laboratory to search for the hybrid states with exotic quantum numbers. A full Partial Wave Analysis (PWA) is performed to the generated Monte Carlo J/ψ→ pηπ data, based on the design of BESⅢ detector, to study the sensitivity of searching for a possible exotic state at BESⅢ. 相似文献
945.
946.
A novel chiral stationary phase (PPHCDN7) was prepared by immobilization of heptakis(6-azido-6-deoxy-2,3-di-O-phenylcarbamoylated)-β-cyclodextrin (PPHCD) onto the surface of amino-functionalized silica gel via multiple urea linkages derived from an extended application of the Staudinger reaction. A wide range of structurally divergent racemic drugs and other compounds were successfully separated into their enantiomers under both normal and reversed-phase conditions. β-Adrenergic blockers and racemic tertiary, secondary and primary amines were readily separated using a mixture of methanol and aqueous triethylammonium acetate buffer. The optimal pH value for the separation falls in the range of 4.65 to 6.30. With atropine and isoproterenol, good enantioseparations with separation factors of >5 were easily attainable. 相似文献
947.
A method has been developed for the determination of ascorbic acid (AA) in individual human neutrophils by capillary zone electrophoresis with electrochemical detection at a carbon fiber microdisk bundle electrode. The natively easily oxidized substances such as glutathione, dopa, dopamine, serotonin, epinephrine do not interfere with the determination of ascorbic acid. A procedure of treating capillaries, which can overcome the influence of the adsorption of the substances in cells on the inner surface wall of the capillary on the migration time and the number of theoretical plates of interests, has been described. The average amount of AA in an individual neutrophil is 0.557 fmol, which is consistent with the literature value. 相似文献
948.
A highly enantioselective Rh(I)-catalyzed intramolecular Alder ene reaction has been developed. The desired products, 3-vinyl, vinyl acetate, and vinyl ether-substitued alpha-methylene-gamma-butyrolactones were formed in high yields. Aldehydes were produced with the formation of gamma-lactones when alcohols were substituted at allylic position in the substrates. All reactions with listed substrates proceeded in over 99% ee. A formal synthesis of (+)-pilocarpine is an excellent example to demonstrate the synthetic utility of this methodology. 相似文献
949.
Yang L 《Physical review letters》2002,88(9):094301
Recently, the thermal conductivity in disordered chains has attracted a lot of attention, including the discussion of the disorder anharmonic and harmonic chains. A natural problem concerns the higher-dimensional disordered lattice system. This paper gives a 2D harmonic lattice model with missing bond defects. When the defect density is large enough, a temperature gradient builds up and a finite heat conduction is found in this model. 相似文献
950.
Jin ZHAI Feng Lian BAI Qing Guo HE Ying Shun LI Lei JIANG Tong LIN Organic Solid Laboratory Research Center for Molecular Sciences Institute of Chemistry The Chinese Academy of Science Beijing 《中国化学快报》2000,11(9)
The hotSPOt in the fields of molecular films focuses on highly ordered, ultrathin filmswith molecularly controllable surface properties. It is attractive tO stUdy supramolecularfunctional POlymeric materials with suitable physical properties and abilities to formorganized superstrUctures at the interfacesl'2'3A. Dendritic macromolecules are a kind ofmaterials which is capable of self-organizing into superstrUctUres'. So a new dendrimerlike POly(Phenylene vinylene)- --hyperbranched conj "… 相似文献