Comparison between the Response of the Northwest Pacific Ocean and the South China Sea to Typhoon Megi(2010)

The upper-ocean responses to Typhoon Megi （2010） are investigated using data from ARGO floats and the satellite TMI. The experiments are conducted using a three-dimensional Princeton Ocean Model （POM） to assess the storm, which affected the Northwest Pacific Ocean （NWP） and the South China Sea （SCS）. Results show that the upwelling and entrainment experiment together account for 93% of the SST anomalies, where typhoon-induced upwelling may cause strong ocean cooling. In addition, the anomalous SST cooling is stronger in the SCS than in the NWP. The most striking feature of the ocean response is the presence of a two-layer inertial wave in the SCS--a feature that is absent in the NWE The near-inertial oscillations can be generated as typhoon wakes, which have maximum flow velocity in the surface mixed layer and may last for a few days, after the typhoon＇s passage. Along the typhoon tracks, the horizontal currents in the upper ocean show a series of alternating negative and positive anomalies emanating from the typhoon.

Dehydrogenation characteristics of ZrC-doped LiAlH4 with different mixing conditions

The catalytic effects of ZrC powder on the dehydrogenation properties of LiAlH4 prepared by designed mixing processes were systematically investigated.The onset dehydrogenation temperatures for the 10 mol% ZrC-doped sample are 85.3 and 148.4℃for the first two dehydrogenation stages,decreasing by 90.7 and 57.8℃,respectively,compared with those of the as-received LiAIH4.The isothermal volumetric measurement indicates that adding ZrC powder could significantly enhance the desorption kinetics of LiAlH4.The reaction constant and Avrami index show that the first dehydrogenation stage is controlled by diffusion mechanism with nucleation rate gradually decreasing and the second stage is a freedom nucleation and subsequent growth process.The microstructures and phase transformation characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS) and Fourier transform infrared spectroscopy(FTIR) reveal that the improved desorption behavior of LiAlH4 is primarily due to the high density of surface defects and embedded catalyst particles on the surface of LiAlH4 particles during the high-energy mixing process.

Efficient production of ultracold polar molecules^(23)Na^(40)K in their absolute ground state via intermediate state of the coupled complex B^(1)Π|ν=4〉^(c)^(3)Σ^(+)|ν=25〉

We report on the efficient creation of a sample of 2.2×10^(4)fermionic polar molecules^(23)Na^(40)K in their rovibrational ground state X^(1)∑^(+)|v=0,J=0>at 247 nK via an intermediate state of the spin-orbit coupled complex B^(1)Π|v=4〉~C^(3)∑^(+)|v=25〉.Compared with the intermediate state of the coupled complex B^(1)Π|v=12〉^(c)^(3)∑^(+)|v=35〉,this intermediate state has the larger Franck-Condon factors for up-and down-leg coupling of stimulated Raman adiabatic passage(STIRAP).We demonstrate this two-photon pathway to the^(23)Na^(40)K ground state molecules and find that the one-way STIRAP transfer efficiency reaches75%.The molecules^(23)Na^(40)K in their rovibrational ground state are an ideal candidate for the quantum simulation and quantum information of ultracold molecules with long-range interaction.

Dynamically assisted pair production for scalar QED by two fields

By solving the quantum Vlasov equation, the dynamically assisted pair production for scalar quantum electrodynamics （QED） is investigated. It is verified that this mechanism still holds true for boson pair production. Two combinations of two electric fields having different time scales under various time delays are considered; it is found that the oscillations of the momentum spectrum and the number density of created bosons decrease with increasing time delay, and the latter has a maximum value when the time delay equals zero. Furthermore, the differences in vacuum pair production between bosons and fermions are also studied, and they are helpful for distinguishing the created bosons from fermions.

Thermodynamic Analysis and Experimental Study on Reaction of CO_2 Gas with Hot Metal

The reaction of CO2 gas with hot metal was investigated based on the thermodynamic analysis and experi- mental results. It shows that both silicon and carbon in hot metal can be oxidized by CO2 gas in the temperature range of 1300-1 500 ℃. When using graphite crucible, temperature has little influence on final mass percent of car bon w[c] because of the carburization effect. Decarburization degree rises significantly with increasing gas injection rate and w[c] can be reduced to 3.2% at most when using MgO crucible. I.ower temperature or higher gas injection rate is propitious to promote desilication reaction, but only 5%- 10% of desilication ratio could be obtained in 20 rain. The final mass percent of silicon W[si] when using MgO crucible is lower than that when using graphite crucible. Ex- perimental results also demonstrate that CO2 injection has no effect on the concentration of manganese, sulfur and phosphorus in hot metal. In view of the weak oxidation ability and temperature drop of hot metal, CO2 gas is sugges- ted to be used as carrier gas in desilication process rather than oxidizing agent.

Pair production in strong SU（2） background fields

强壮的苏(2 ) 计量器 chromoelectric 领域里的费米子粒子对生产以一个古典方法用 Boltzmann-Vlasov 方程被学习。在古典描述的一个 preproduction 过程的存在用 non-Abelian 粒子生产的分发进化被显示出。发现粒子数字密度的分发在二个岛上被集中并且当它演变，在颜色费用范围上显示出一个裂口有趣，最终到达与这个领域的振幅和变化有关的一个稳定的状态。

Asymmetric pulse effects on pair production in polarized electric fields

Using the Dirac–Heisenberg–Wigner formalism,effects of the asymmetric pulse shape on the generation of electronpositron pairs in three typical polarized fields,i.e.,linear,middle elliptical and circular fields,are investigated.Two kinds of asymmetries for the falling pulse length,short and elongated,are studied.We find that the interference effect disappears with the shorter pulse length and that the peak value of the momentum spectrum is concentrated in the center of the momentum space.In the case of the extending falling pulse length,a multiring structure without interference appears in the momentum spectrum.Research results show that the momentum spectrum is very sensitive to the asymmetry of the pulse as well as to the polarization of the fields.We also find that the number density of electronpositron pairs under different polarizations is sensitive to the asymmetry of the electric field.For the short falling pulse,the number density can be significantly enhanced by over two orders of magnitude.These results could be useful in planning high-power and/or high-intensity laser experiments.