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A compact diode-end-pumped passively Q-switched Nd3+:GdVO4/Cr4+:YAG self-Raman laser at 1176?nm is demonstrated. When the T0 = 80% Cr4+:YAG saturable absorber is inserted into the cavity, the maximum Raman laser output reaches 175?mW with 3.8?W incident pump power. The optical conversion from incident to the Raman laser is 4.6% and the slope efficiency is 6.5%. The pulse energy, duration, and repetition frequency of the first stokes laser are 4.5??J, 1.8?ns, and 38.5?kHz, respectively. There is strong blue emission (about 350?400?nm) can be observed in the Nd3+:GdVO4 crystal when the process of stimulated Raman scattering occurs, which is induced by the upconversion of the Nd3+ ions.

The influence of laser linewidth Γ1 on laser cooling of atoms was investigated theoretically by using a diffusing phase model. The final temperature which can be achieved by Doppler cooling or sub-Doppler cooling in phase fluctuating laser field is presented. It was found that the natural linewidth Γn of the transition used for cooling the atoms is an important quantity in evaluating the influence of Γ1 under Doppler cooling mechanism, and the laser linewidth has little effect on the final temperature under sub-Doppler cooling mechanism because the laser detuning is very large in this case.

To investigate the effect on platelet activity and short time clinic benefit of intracoronary or intravenous tirofiban bolus administration to patients with acute ST-segment elevation myocardial infarction undergoing emergency interventional treatment. Selected 90 patients with acute ST-segment

The squeezed coherent thermal state is considered. Its various coherent representations, including Q-, P-and Bargmann representations are introduced. The analytic formula for the photon number distribution of such a quantum state is obtained directly from the Bargmann representation. The effects of the squeezing and the thermal noise on the photon distribution are discussed.

This paper reports on the excited state Faraday anomalous dispersion spectrum (FADS) of rubidium based on transition 5 P 3 2 → 5 D 5 2 . Theoretical analysis and experimental studies have been made. The results showed that the peak transmission occurred at the central frequency of the transition, there was an optimal magnetic intensity at a certain temperature and pump power, and peak transmission increased with the enhancement of pump power. 16% transmission was predicted when the density of 5 P 3 2 atoms was sufficient.

The force to which Cs atoms are subjected in the one-dimensional magneto-optical trap (lD-MOT) is calculated, and properties of this force are discussed. Several methods to increase the number of Cs atoms in the lD-MOT are presented on the basis of the analysis of the capture and escape of Cs atoms in the ID-MOT.

This paper reports what is to our knowledge the first demonstration of Zeeman absorption Faraday anomalous dispersion optical filter (hereafter abbreviated to FADOF/Zeeman). The mutual relations among passband, tuning capability, cell temperature and magnetic field of FADOF/Zeeman have been studied theoretically and experimentally. The results showed that the single passband of FADOF/Zeeman was about 1 GHz, which is 3 times less than the passband of FADOF. The tuning capability was about 1 GHz/0.01 T.

In this paper, wave concept iterative process is presented to analysis the LTCC multilayer antenna. The method solves the boundary condition of the discontinuity circuit in term of waves. The transmission lines theory describes the relationship of waves between the layers. The circuit characteristic parameters are calculated by the method effectively. The results show a good agreement compared with the existed simulation data.

We report a digital space optical communication system with new features both in the transmitting and in the receiving ends. The diode laser source is stabilized to within ±100 kHz by locking its frequency to the transmission peak of a Faraday anomalous dispersion optical filter (FADOF). The optical filter in the receiver uses two FADOF’s that are linked to eliminate the multipeak structure and achieve a single-peak bandwidth of ~1 GHz. The detection sensitivity of this system is 23 times higher than that of a system with a traditional interference filter.

The active decoy environment of anti-radiation weapon face is introduced, and the position between the radar and the decoy is analyzed. The new way of distinguish multiple source signal by turning PRSpsila antenna is given. Then the feasibility and the limitation are analyzed based on the discussing and testing.

As an effective heat transfer medium, Nanofluid is used widely in heat transfer field. However, due to the contradiction between the heat conductivity coefficient of nanofluid and the cost of nanoparticles, a new mixed nanofluid is developed. In order to investigate the natural convection heat transfer characteristics and the interaction mechanism between nanoparticles, the lattice Boltzmann equations of nanofluid flow and temperature fields are deduced by multi-scale technique based on considering the interaction forces between nanoparticles, and the lattice Boltzmann model of Cu/Al2O3-water mixed nanofluid is established by coupling the evolution equations of flow with temperature fields. Nanoparticles distribution in enclosure and interaction forces between nanoparticles are investigated, it is found that Brownian motion force is far bigger than any other forces, and the effects of temperature difference driving force and Brownian motion force on nanoparticles distribution are biggest. In addition, the effects of nanoparticles fractions and Rayleigh number on natural convection are investigated, and the natural convection heat transfer characteristics of mixed nanofluid (Cu/Al2O3-water) are compared with those of single metal nanoparticle nanofluid (Al2O3-water). It is found that the mixed nanofluid has a higher heat transfer characteristic than other common nanofluid.

To investigate the risk factors for occurrence of electrical storm in the patients with acute ST segment elevation myocardial infarction (STEMI) when treat them by percutaneous coronary intervention (PCI) and provide evidence for prospective nursing. Collected the clinical data of 280 patients with