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101.
A. Waltrop S. K. Mitra A. I. Flossmann H. R. Pruppacher 《Journal of Atmospheric Chemistry》1991,12(1):1-17
An experimental study involving the Mainz vertical wind tunnel is described where the rate of SO2 removed from the air by freely suspended water drops was measured for SO2 concentrations in the gas phase ranging between 50 and 500 ppb, and for various H2O2 concentrations in the liquid phase. In a first set of experiments, the pH inside the SO2 absorbing drops was monitored by means of colour pH indicators added to the drops. In a second set of experiments, the amount of SO2 scavenged by the drops was determined as sulfate by an ionchromatograph after the drops had been removed from the vertical air stream of the wind tunnel after various times of exposure to SO2. The results of our experimental study were compared with the theoretical gas diffusion model of Walcek and Pruppacher which was reformulated for the case of SO2 concentrations in the ppbv(v) range for which the main resistance to diffusion lies in the gas phase surrounding the drop. Excellent agreement between experiment and theory was obtained. Encouraged by this agreement, the theory was used to investigate the rate of sulfate production inside a drop as a function of pH. The sulfate production rate, which includes transport and oxidation, was compared with the production rate based on bulk equilibrium, as cited in the literature. 相似文献
102.
从高斯光束经过光学系统的传输与变换规律出发,借助于高斯括号的性质,研究了激光束光学系统的变焦特性,导出了机械补偿式激光束变焦系统的变焦方程及补偿点位置方程,并给出了计算实例。 相似文献
103.
104.
本文叙述了RAP-10仪中一种新型的差动放大器。进行了理论分析、模拟计算和实验。结果表明:这种新型的差动放大电路与通用的差动放大电路相比,具有宽带频率补偿作用。是一种宽带差动放大器。关键词 相似文献
105.
D. Perner U. Platt M. Trainer G. Hübler J. Drummond W. Junkermann J. Rudolph B. Schubert A. Volz D. H. Ehhalt K. J. Rumpel G. Helas 《Journal of Atmospheric Chemistry》1987,5(2):185-216
Using long path UV absorption spectroscopy we have measured OH concentrations close to the earth's surface. The OH values observed at two locations in Germany during 1980 through 1983 range from 0.7×106 to 3.2×106 cm-3. Simultaneously we measured the concentrations of O3, H2O, NO, NO2, CH4, CO, and the light non methane hydrocarbons. We also determined the photolysis rates of O3 and NO2. This allows calculations of OH using a zero dimensional time depdendent model. The modelled OH concentrations significantly exceed the measured values for low NO
x
concentrations. It is argued that additional, so far unidentified. HO
x
loss reactions must be responsible for that discrepancy. 相似文献
106.
Fu Liangkui 《地球科学》1986,(2)
本文阐明了反向变分流系统地下电流的分布特点和规律。文中还给出了反向变分流电阻率法视电阻率的异常表达式,计算了装置系数和电流分配系数之间的关系,并阐明其规律和作用。最后,作为一个例子,分析了水平地层上反向变分流电测深法视电阻率的异常分布规律,并指出它在勘探中的作用。 相似文献
107.
108.
The ultraviolet absorption cross sections were measured for CF3Br, CF2ClBr, CF2Br-CF2Br, CF2Br2, CHF2Br, CHFBr-CF3, CH2Br-CF3, CHClBr-CF3 in the wavelength range 190–320 nm at 295 K. The photolysis is concluded to be the minor atmospheric sink for CHF2Br, CHFBr-CF3, CH2Br-CF3, CHClBr-CF3. 相似文献
109.
110.
The analysis and interpretation of coda waves have received increasing attention since the early seventies. In the past few years interest in this subject has spread worldwide, and the study of high-frequency seismic coda waves has become a very important seismological topic. As a conclusion of the studies accomplished in this time, coda waves are considered the result of scattering processes caused by heterogeneities acting on seismic waves.P andS waves play a particularly important role in this interaction. The process introduces an attenuation which, added to the intrinsic absorption, gives the observed apparent attenuation. Therefore, coda waves constitute a thumbprint left by the heterogeneities on the seismograms. Coda waves offer decisive information about the mechanism of how scattering and attenuation take place. This review describes coda waves in detail, and summarizes the work done in this subject to 1986. The relation between coda waves and attenuation in the context of research on seismic scattering problems is stressed. Particular attention has been given to the application of coda waves to estimate source and medium parameters. The state-of-the-art of the temporal variations of coda wave shape, and the possible use of these variations as an earthquake precursor also are presented. Care has been taken to introduce the statistical models used to deal with the heterogeneities responsible for scattering. 相似文献