大气探测红外分光辐射计Ⅱ型模样

报道了大气探测红外分光辐射计Ⅱ型(ASIS-2)模样,它具有20个通道,可以从卫星探测大气温度廓线和水汽垂直分布.它与美国TIROS-N/NOAA气象卫星上的高分辨率红外辐射探测仪(HIRS)相比,在光学、电子学和机械等方面都作了改进.其仪器灵敏度优于HIRS-1仪器,而与HIRS-2接近.它具有可增加2个红外通道和多个可见光通道的潜力.     

电离层时域探测方法

给出了各向同性分层半空间等离子体对时域电磁脉冲后向散射的有关公式，得出了反抛物层时域响应的解析表达式，并利用时频分析方法演出了电子密度分布。     

Measurement System of Uniformity between Breech Horizontal Platform and Datum Tube Axis of Rocket Artillery

The purpose of this development is to detect the parallelism between the breech horizontal platform and the datum tube axis of the rocket artillery. The located aiming mechanism at the muzzle and located adjustment mechanism at the breech are designed in the system. Besides those, the system also uses an autocollimator with accuracy of 1″ and a collimating mirror together to determine the axis of the datum tube. An electronic level with accuracy of 2″ is employed to measure and display the value of the included angle and the parameter of the inclined direction. The entire accuracy of this system is σ≤± 9.1″. This paper describes the composition and the operating principle of the system and analyzes the accuracy. The development of this system supplies reliable measurement method for new rocket artilleries and artilleries, and this technology is of a good application prospect.     

潜体在非均质流体中的平衡位置与平衡过程

以探空气球为例,讨论潜体在非均质流体中的平衡位置与平衡过程.     

Radiometric observations of the 752.033-GHz rotational absorption line of H2O from a laboratory jet

The intensity and lineshape of the Doppler-broadened 752.033-GHz (2₁₁ 2₀₂) rotational transition of H₂O has been studied passively using a high-resolution two-stage heterodyne radiometer with single-sideband system noise temperature of 45,000 K. The purpose of the experiments was to demonstrate the observability at submillimeter wavelengths of a high-altitude rocket plume simulated by a laboratory H₂O jet in a vacuum chamber. First-stage mixing was accomplished by means of a GaAs Schottky diode with first local-oscillator power supplied by a CO₂-laser pumped formic-acid laser (761.61 GHz), generating and X-band IF signal. Second localoscillator power was provided by a tunable C-band source. One-MHz resolution capability was obtained by means of a 3-GHz waveguide cavity filter with only 9-dB insertion loss. In the H₂O jet experiments, the center frequency of the line was determined to within 1 MHz of the previously reported value. A rotational temperature 75 K, a linewidth 5 MHz, and a Doppler shift 3 MHz (from a 45-degree rotation of the flow direction) were measured with the line-of-sight intersecting the jet axis at a distance downstream of 30 nozzle diameters. These absorption data were ogtained against continuum background radiation sources at temperatures of 1175 and 300 K.     

最小二乘B样条函数在火箭发动机数据处理中的应用

在固体火箭发动机地面试验数据处理中,通过应用最小二乘三次B样条函数拟合的方法,进行野值辨识和修复。文中阐述了实际应用中的步骤及应注意的几点问题。为避免常规的控制序列中含有野值而影响数据辨识的问题,提出差别选取控制点循环过滤的方法,实现精度更高的野值辨识。进而采用门限判别方法,实现野值的修复。通过实测数据处理的应用表明,该算法对单个和成片野值的辨识度都很高,适用于火箭发动机地面试验数据处理。     

电离层垂直探测中扰动观测模式研究

电离层高频反射回波的多普勒频移观测是研究电离层扰动的一个重要方法.利用电离层垂直探测中的组合脉冲控制和回波相位测量分析方法,开发并实现了一种电离层扰动观测模式.实验观测表明,新开发的观测模式在电离层高频反射回波为窄带信号的情况下,可实时获得高精度多普勒频高图,并给出电离层扰动速度的时空变化曲线,能够满足电离层扰动观测研究的需要.     

水火箭的制作与发射——初中物理教学课外活动拓展

物理课外实验能让学生真正动手操作、体验,从而提高学生的物理核心素养.水火箭的制作与发射,蕴含知识面广,发射效果震撼,能让学生对物理与科技的联系有直观深刻的认识.     

虚拟震源测深法及其在INDEPTH-3台阵中的应用

基于中美合作项目INDEPTH第3期在青藏高原布设的台站,使用虚拟震源测深法研究青藏高原中部的地壳厚度。结果显示,拉萨地体和羌塘地体的地壳结构存在巨大差异。拉萨地体的地壳厚度大约为57 km,与艾里均衡说预测的地壳厚度基本一致,说明拉萨地体的地壳结构比较简单。羌塘地体的地壳厚度为60~75 km,向北有增厚趋势,明显较艾里均衡说预测的地壳厚,说明羌塘地体地壳结构比较复杂,原因有可能是羌塘地体下存在高温流体和低速带,或者与印度板块岩石圈在班公湖-怒江缝合带以北向下俯冲有关。     

复杂密度场测量中的莫尔层析重建技术

将一种新的莫尔层析重建算法应用于复杂流场测量.该算法由莫尔偏折原理和网格重建技术推导得出,直接使用光线偏折角进行修正迭代,适用于有限角采样和包含遮挡物等非完全数据条件下的层析重建.应用该算法,对火箭燃气射流场和高超音速流场的莫尔偏折图进行了处理和计算,重建出流场截面的密度分布,并对重建结果进行了分析.