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We demonstrate a pulse-duration tunable Tm3+-doped pulsed all-fiber master oscillator power amplifier (MOPA) operating at a central wavelength of 1908 nm. By using acousto-optic(AO) external modulation, the amplified laser pulse shows a tuning range having pulse durations from 66.5 ns to 8.0 μs and a repetition rate of 100 kHz-2 MHz. The laser achieved a maximum average power of 28.1 W and a corresponding energy of 28.1 μJ at 1MHz with a 3 dB linewidth of 0.63 nm and a beam quality factor of Mx2=1.25 and My2=1.32. The ASE suppression ratio is 50 dB and the corresponding total amplifier gain is 27.5 dB. To the best of our knowledge, it is the highest average output power and slope efficiency (∼51.0%) achieved using AO external modulation in a Tm3+-doped pulsed fiber amplifier. [ABSTRACT FROM AUTHOR]

In this study, ginsenoside Rg3-loaded PEGylated liposomes were prepared and optimized using the Box- Behnken design. These liposomes were characterized, the cumulative release profiles were investigated and compared with ginsenoside Rg3-loaded liposomes in vitro. To improve the stability ginsenoside Rg3-loaded PEGylated liposomes were freeze-dried and the lyoprotectants to be added were screened. The results showed that the liposomes have a small particle size (152.58±0.74 nm) and spherical shape. The encapsulation efficiency and drug-loading rate were approximately 85.24±1.02 and 7.44±0.08 %, respectively. For lyoprotectants, 2 % lactose was chosen as the lyophilized protectant according to the appearance, re-dispersity, particle size, and entrapment efficiency of lyophilization of ginsenoside Rg3- loaded PEGylated liposomes. In vitro release showed that ginsenoside Rg3-loaded PEGylated liposomes showed a more obvious sustained release effect, which suggests that ginsenoside Rg3-loaded PEGylated liposomes might enhance the therapeutic effect of ginsenoside Rg3. [ABSTRACT FROM AUTHOR]

An analytical study on the vibration and energy flow behaviors of a coupled cylindrical shell-plate structure is presented. An analytical model capable of handling general boundary and coupling conditions is developed in which the interactions of all internal forces and moments for both the shell and plate have been taken into account at the junction via four types of coupling springs with arbitrary stiffness and covering all the degrees of freedom, and each of the plate and shell displacement functions is expressed as the superposition of a two-dimensional Fourier series and several supplementary functions. The unknown expansions coefficients are obtained using the Rayleigh-Ritz procedure. The effectiveness and accuracy of the present solution are validated against the FEM results. The energy flow behaviors through this structure are investigated through parametric power flow and structural intensity analysis. The contribution of internal forces or moments to the power flow and the influence of key system parameters on the energy flow are analyzed numerically, including coupling locations, coupling conditions, boundary conditions, and excitation location. The results shed light on the effects of system parameters on the energy flow behaviors of the class of coupled shell-plate structure. [ABSTRACT FROM AUTHOR]

In this paper a two-dimensional (2-D) axisymmetric physical model to express the temperature and thermal stress in damage process of silicon plate irradiated by annular millisecond laser is presented, and analytical solutions of 2-D heat conduction equation and thermo-elastic equations are obtained using integral transform method. Then, the transient temperature fields and the thermal stress of silicon are simulated, and the locations of the maximum temperature rise and the maximum tensile stress are obtained. Finally, the melting damage threshold and the thermal stress damage threshold of silicon are investigated, and the damage threshold changing with irradiating time is discussed. Modelling results show that the damage form of silicon irradiated by annular millisecond laser is melting damage mainly. [ABSTRACT FROM AUTHOR]

A finite element method (FEM) model for simulating long pulsed laser interaction with gallium arsenide (GaAs) at 0.53 µm wavelength for a 1 ms pulse width is established. The distributions of transient temperature fields before melting in different cases have been obtained and the damage characteristics were estimated. Additionally, the decomposition damage thresholds are also given. Numerical results show that heat conduction affects the whole process of long pulsed laser interaction and its damage mechanism is mainly due to thermal effects. The temperature of the centre is highest and rises fastest on the irradiated surface, where it could be damaged first. As the laser energy density increases the occurrence time of the damage gradually advances. [ABSTRACT FROM AUTHOR]

The unsteady characteristics of tip-leakage flow in axial fans with circumferential skewed blades were investigated at off-design conditions using particle image velocimetry (PIV) and wall pressure test. Two circumferential skewed fans, with the blade skew angles at 8.3° forward and backward, respectively, were investigated in this study. The instantaneous flow field in tip clearance region was measured using PIV at peak pressure condition. The static pressure fluctuations near blade tip were captured at off-design conditions using pressure sensors mounted on casing wall. From the measured results, the structure and instantaneous characteristics of tip-leakage flow in circumferential skewed fans were analysed. The tip-leakage vortex instability and its relation with circumferential skewed blades, to expand stall-free operation range of axial fans, were discussed. The forward-skewed blade is found to be effective in controlling tip-leakage flow to expand stall-free operation range at off-design conditions. [ABSTRACT FROM AUTHOR]

From November 2004 to October 2005, twenty blood biochemical indices, i. e., total protein, serum albumin, serum globulin, total bilirubin, direct bilirubin, indirect bilirubin, blood glucose, serum urea nitrogen, serum creatine, total cholesterol, triglyceride, aspartate amino transferase, alanine amino transferase, alkaline phosphatase, serum creatine kinase, hydroxybutyrate dehydrogenase, lactic dehydrogenase, serum calcium ion, inorganic phosphate, and magnesium ion, of 10 female Grus japonensis adults in their wintering, reproduction, and migration periods in Zhalong Nature Reserve were analyzed by automatic biochemical analyzer. Significant differences (P < 0.05 or P < 0.01) were observed in the test indices except serum total protein, serum globulin, and blood glucose among the three life periods, which suggested that the serum total protein, serum globulin, and blood glucose could be used as the reliable references of blood biochemical indices of female G. japonensis, while the year-round dynamics of the other 17 indices reflected the physiological characteristics and ecological adaptability of female G. japonensis in its different periods in one year. When using these 17 indices as the references of the blood biochemical indices of female G. japonensis, the physiological period should be considered. [ABSTRACT FROM AUTHOR]

We measured and analyzed the subthreshold degradation of the gate-all-around (GAA) silicon nanowire field-effect transistors with the length of 300/500 nm and the radius of 5 nm. An analytical model incorporating the effect of interface traps quantitatively explained the measured subthreshold swing (SS) degradation. A simple electrostatic argument showed that the GAA device had smaller degradation of SS values than planar devices for the same interface trap densities. [ABSTRACT FROM PUBLISHER]