关于数控设备的"实话实说"

富春江富士水电设备有限公司主要生产水轮发电机组及电站配套设备.随着电力行业的发展,用户对供货时间及供货的质量提出了新的要求.水电设备和加工设备有很大的不同,工厂只进行部件装配,整机无法在工厂装配.因此,数控机床的推广在我公司显得很重要.     

Evolution of Small Scale Density Perturbations of Plasma and Charged Aerosol Particles in Polar Mesospheric Summer Echoes （PMSE） Layers

Time evolution of ionospheric D-region plasmas including the perturbations of electrons and charged aerosol particles is investigated under the conditions of po...     

Lower-Hybrid Drift Instability in Modified Harris Current Sheet

Lower-hybrid drift instability （LHDI） in a Harris current sheet including a uniform background distribution is investigated in linear local kinetic theory. It is found that the introduction of a uniform background distribution reduces the growth rate and real frequency of LHDI at all wavelengths. Some physical explanations about the effects of the background distribution are provided.     

Scattering of Electromagnetic Waves by Drift Vortex in Plasma

In a quasi-two-dimensional model, the scattering of incident ordinary electromag- netic waves by a dipole-electrostatic drift vortex is studied with first-order Born approximation. The distribution of the scattering cross-section and total cross-section are evaluated analytically in different approximate conditions, and the physical interpretations are discussed. When the wavelength of incident wave is much longer than the vortex radius （kia〈〈1）, it is found that the angle at which the scattering cross-section reaches its maxim depends significantly on the approximation of the parameters of the vortex used. It is also found that the total scattering cross-section has an affinitive relation with the parameters of the plasma, while it is irrelevant to the frequency of the incident wave in a wide range of parameters of the vortex. In a totally different range of parameters when incident wave is in the radar-frequency range （then kia 〈〈 1, the wavelength of incident wave is much shorter than the vortex radius）, the numerical procedure is conducted with computer in order to obtain the distribution and the total expression of the scattering crosssection. Then it is found that the total scattering cross-section in the low frequency range is much larger than that in high frequency range, so the scattering is more effective in the low frequency range than in high frequency range.     

HPLC-MS/MS法测定猪肉中克伦特罗、莱克多巴胺及沙丁胺醇

采用高效液相色谱-串联质谱法测定猪肉中克伦特罗、莱克多巴胺及沙丁胺醇,内标法定量。结果显示,在1.0～50.0 ng/mL浓度范围内3种化合物线性关系良好,线性相关系数均大于0.999,方法检出限为0.2μg/kg时, 3种化合物响应值均大于3,方法定量限为0.5μg/kg时, 3种化合物响应值均大于10。在1.0, 4.0和8.0μg/kg浓度水平上加标回收率为81.0%～94.0%,相对标准偏差(n=7)分别为1.83%, 3.07%和3.50%,满足方法验证要求。     

Collisional Sheath in the Electronegative Radio-Frequency Plasma

A model of collisional RF sheath with negative ions is discussed in this paper. The influences of collision and negative ions on the parameters of the sheath are studied through numerical simulation. It is found that when the collision coefficient increases and the RF power is fixed, the electrode potential and sheath electric field potential increase, the electrode current and thickness of the sheath decrease. When the negative ion content changes, the same phenomenon Occurs,     

An Obliquely Propagating Electromagnetic Lower-Hybrid-Drift Instability in Plasmas with Negative Ions

In this study, by employing a local fluid theory for warm plasma containing negative ions, an obliquely propagating electromagnetic instability in the lower hybrid frequency range driven by cross-field currents or relative drifts between electrons and ions was investigated. It is found that the growth rate of the lower-hybrid-drift instability （LHDI） can be controlled by appropriate selection of the propagation direction, the wave number and the relative population of the negative ions.     

Numerical Simulation of Tripolar Vortex in Dusty Plasma with Sheared Flow and Sheared Magnetic Field

This article presents a study we have made of one class of coherent structures of the tripolar vortex. Considering the sheared flow and sheared magnetic field which are common in the thermonuclear plasma and space plasma, we have simulated the dynamics of the tripolar vortex. The results show that the tripolar vortex is largely stable in most cases, but a strongly sheared magnetic field will make the structure less stable, and lead it to decays into single vortices with the large space scale. These results are consistent with findings from former research about the dipolar vortex.     

纺织品整理的未来发展

总结纺织品整理过程中过去的进展，以预期该领域在前处理，干燥，染色印花，整理，涂层等工序中未来的发展方向。     

关于数控设备的“实话实说”

富春江富士水电设备有限公司主要生产水轮发电机组及电站配套设备。随着电力行业的发展，用户对供货时间及供货的质量提出了新的要求。水电设备和加工设备有很大的不同，工厂只进行部件装配，整机无法在工厂装配。因此，数控机床的推广在我公司显得很重要。