Creat membership Creat membership
Sign in

Forgot password?

Confirm
  • Forgot password?
    Sign Up
  • Confirm
    Sign In
home > search

Now showing items 33 - 48 of 1311

  • Unusual thermal fatigue behaviors in 60 nm thick Cu interconnects

    J. Zhang   J.Y. Zhang   G. Liu   Y. Zhao   X.D. Ding   G.P. Zhang   J. Sun  

    Download Collect
  • Circulating GLP-1 and CCK-8 reduce food intake by non-vagal mechanisms

    J. Zhang   R.C. Ritter  

    Download Collect
  • Statistical properties of a 2D granular material subjected to cyclic shear

    J. Zhang   T. S. Majmudar   A. Tordesillas   R. P. Behringer  

    Download Collect
  • Synchronization Control of Neural Networks With State-Dependent Coefficient Matrices

    J. Zhang   X. Zhao   J. Huang  

    Download Collect
  • Numerical studies of dispersion and flammable volume of hydrogen in enclosures

    J. Zhang   M.A. Delichatsios   A.G. Venetsanos  

    This paper presents a numerical study of dispersion and flammable volume of hydrogen in enclosures using a simple analytical method and a computational fluid dynamics (CFD) code. In the analytical method, the interface height and hydrogen volume fraction of the upper layer are obtained based on mass and buoyancy conservation while the centreline hydrogen volume fraction is derived from similarity solutions for buoyant jets. The two methods (CFD and analytical) are used to simulate an experiment conducted by INERIS, consisting of a 1 g/s hydrogen release for 240 s through a 20 mm diameter orifice into an enclosure. It is found that the predicted centreline hydrogen concentration by both methods agrees with each other and is also in good agreement with the experiment. There are however differences in the calculated total flammable volume because the analytical method does not consider local mixing and diffusion in the upper layer which is assumed uniformly well mixed. The CFD model, in comparison, incorporates the diffusion and stratification phenomena in the upper layer during the mixing stage.
    Download Collect
  • Manipulating atomic coherence and interference in a coupled atom-cavity system

    J. Zhang   X. Wei   G. Hernandez   Y. Zhu  

    Collective coupling of multiple atoms with a cavity mode produces two normal modes that are separated in energy by Vacuum Rabi splitting. We show that quantum coherence and interference can be produced by a control laser that couples the atoms confined in the cavity mode from free space, which leads to suppression of the normal mode excitation, or polariton excitation of the cavity-atom system. The control laser splits the normal mode of the cavity-atoms system and opens two excitation channels. The destructive quantum interference between the two channels renders the cavity-atoms system opaque to the light coupled into the cavity mode. We demonstrate suppression of the normal mode (polariton) excitation by the destructive quantum interference in an experiment with cold Rb atoms confined in an optical cavity.
    Download Collect
  • Thermal process of iron silicides prepared by Magnetron sputtering

    J. Zhang   Q. Xie   Y. Liang   W. Zeng   Q. Xiao   Q. Chen   D. Ma   Y. Wang   Koji Yamada   Jiaolian Luo  

    Download Collect
  • Coercivity mechanism of nanocomposite Sm-Co/Fe multilayer films

    J. Zhang   Y. Li   F. Wang   B. Shen   J. Sun  

    The coercivity mechanism of nanocomposite Sm-Co/Fe multilayer films was investigated. It was concluded that the magnetization reversal mechanism of Sm-Co/Fe multilayer films is dominated mainly by domain wall pinning instead of nucleation. The addition of Cu layer between the hard and soft layers causes the change in grain boundary as well as the large variation in anisotropy in the hard layer after annealing, which leads to a strong increase in domain wall pinning, and therefore a significant improvement of the coercivity. This study indicates the potentials of this method to control and improve the magnetic property of nanocomposite multilayer films.
    Download Collect
  • Performance and Stability of Novel Biphasic Amine Absorbents for CO2 Capture

    J. Zhang   O. Nwani   J. Chen   R. Misch   D.?W. Agar  

    Download Collect
  • An Experimental Research of the Performance of the Trapped- Vortex Combustor

    j. Zhang   j. Xu   J. Su   and m. Wei   Nanjing University of Aeronautics and Astronautics   Nanjing  

    Download Collect
  • CREAMS-WT Application for the Upper Kissimmee Region, Florida

    H. Zhao   J. Zhang   R. T. James,  

    Download Collect
  • An orbital period investigation of the Algol-type eclipsing binary VW Hydrae

    J. Zhang   S. Qian   B. Soonthornthum  

    Orbital period variations of the Algol-type eclipsing binary, VW Hydrae, are analyzed based on one newly determined eclipse time and the other times of light minima collected from the literature. It is discovered that the orbital period shows a continuous increase at a rate of dP/dt = +6.34*10-7 d yr-1 while it undergoes a cyclic change with an amplitude of 0.0639 d and a period of 51.5 yr. After the long-term period increase and the large-amphtude period oscillation were subtracted from the O-C curve, the residuals of the photoelectric and CCD data indicate a small-amplitude cyclic variation with a period of 8.75 yr and a small amplitude of 0.0048d. The continuous period increase indicates a conservative mass transfer at a rate of dM2/dt = 7.89*10-8 M⊙ yr-1 from the secondary to the primary. The period increase may be caused by a combination of the mass transfer from the secondary to the primary and the angular momentum transfer from the binary system to the circumbinary disk. The two cyclic period oscillations can be explained by light-travel time effects via the presence of additional bodies. The small-amplitude periodic change indicates the existence of a less massive component with mass M3 > 0.53 M⊙, while the large-amplitude one is caused by the presence of a more massive component with mass M4 > 2.84 M⊙. The ultraviolet source in the system reported by Kviz & Rufener (1987) may be one of the additional components, and it is possible that the more massive one may be an unseen neutron star or black hole. The rapid period increase and the possibility of the presence of two additional components in the binary make it a very interesting system to study. New photometric and high-resolution spectroscopic observations and a detailed investigation of those data are required in the future.
    Download Collect
  • Circulating GLP-1 and CCK-8 reduce food intake by non-vagal mechanisms

    J. Zhang   R.C. Ritter  

    Download Collect
  • Transient charge and energy balance in graphene induced by ultrafast photoexcitation

    J. Zhang   J. Schmalian   T. Li   J. Wang  

    Ultrafast optical pump-probe spectroscopy measurements on monolayer graphene reveal significant optical nonlinearities. We show that strongly photoexcited graphene monolayers with 35 fs pulses quasi-instantaneously build up a broadband, inverted Dirac-fermion population. Optical gain emerges and directly manifests itself via a negative conductivity at the near-infrared region for the first 200 fs, where stimulated emission completely compensates for absorption loss in the graphene layer. To quantitatively investigate this transient, extremely dense photoexcited Dirac-fermion state, we construct a two-chemical-potential model, in addition to a time-dependent transient carrier temperature above the lattice temperature, to describe the population inverted electronic state metastable on the time scale of tens of femtoseconds generated by a strong exciting pulse. The calculated transient optical conductivity reveals a complete bleaching of absorption, which sets the saturation density during the pulse propagation. In particular, the model calculation reproduces the negative optical conductivity at lower frequencies in the states close to saturation, corroborating the observed femtosecond stimulated emission and optical gain in the wide near-infrared window.
    Download Collect
  • Evaluation of generalized linear models for soil liquefaction probability prediction

    J. Zhang   L. M. Zhang   H. W. Huang  

    A soil deposit subjected to seismic loading can be viewed as a binary system: it will either liquefy or not liquefy. Generalized linear models are versatile tools for predicting the response of a binary system and hence potentially applicable to liquefaction prediction. In this study, the applicability of four generalized linear models (i.e., logistic, probit, log-log, and c-log-log) for liquefaction potential evaluation is assessed and compared. Eight liquefaction models based on the four generalized linear models and two sets of explanatory variables are evaluated. These models are first calibrated with past liquefaction performance data. A weighted-likelihood function method is used to consider the sampling bias in the calibration database. The predicted liquefaction probabilities from various models are then compared. When liquefaction probability is small, the predicted liquefaction probability is sensitive to the regression models used. The effect of sampling bias is more marked in the high cyclic stress ratio region. The eight models are finally ranked using a Bayesian model comparison method. For the generalized linear models examined, the logistic and c-log-log regression models are most supported by the past performance data. On the other hand, the probit and c-log-log regression models are much less applicable to liquefaction prediction.
    Download Collect
  • EGF signalling pathway regulates colon cancer stem cell proliferation and apoptosis

    Y. Feng   X. Dai   X. Li   H. Wang   J. Liu   J. Zhang   Y. Du and L. Xia  

    Cancer stem cells (CSCs) compose a subpopulation of cells within a tumour that can self-renew and proliferate. Growth factors such as epidermal growth factor (EGF) and basic fibroblast growth factor (b-FGF) promote cancer stem cell proliferation in many solid tumours. This study assesses whether EGF, bFGF and IGF signalling pathways are essential for colon CSC proliferation and self-renewal.
    Download Collect
1 2 3 4 5 6 7 8 9 10

Contact

If you have any feedback, Please follow the official account to submit feedback.

Turn on your phone and scan

Submit Feedback