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1. Introduction The quasi-biennial oscillation (QBO) of the mean zonal wind in the equatorial stratosphere was discov- ered by Reed et al. (1961) and Veryard and Ebdon (1961). Later, Funk and Garnham (1962) and Ra- manathan (1963) were the first to descri… 相似文献
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W. Kirchner F. Welter A. Bongartz J. Kames S. Schweighoefer U. Schurath 《Journal of Atmospheric Chemistry》1990,10(4):427-449
A liquid jet of 90 m diameter and variable length has been utilized to determine absorption rates and, hence, mass accommodation coefficients , of atmospheric trace gases. The compounds investigated are HCl (0.01), HNO3 (0.01), N2O5 (0.005), peroxyacetyl nitrate (>0.001), and HONO (0.005). It is concluded that the absorption of these trace gases by liquid atmospheric water is not significantly retarded by interfacial mass transport. The strengths and limitations of the liquid jet technique for measuring mass accommodation coefficients are explored. 相似文献
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P.A. LaViolette 《Planetary and Space Science》2005,53(4):385-393
Hammer et al. (Climatic Change 35 (1997) 1) report the presence of regularly spaced acidity peaks (H+,F-,Cl-) in the Byrd Station, Antarctica ice core. The event has a duration of about one century and falls at the beginning of the deglacial warming. Volcanism appears to be an unlikely cause since the total acid deposition of this event was about 18 fold greater than the largest known volcanic eruption, and since volcanic eruptions are not known to recur with such regularity. We show that the recurrence period of these peaks averages to 11.5±2.4 years, which approximates the solar cycle period, and suggest that this feature may have an extraterrestrial origin. We propose that this material may mark a period of enhanced interstellar dust and gas influx modulated by the solar cycle. The presence of this material could have made the Sun more active and have been responsible for initiating the warming that ended the last ice age. 相似文献
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对于石灰岩地层出水量小于5m^3／h的机井，采取单一的洗井增水方法效果一般不明显。笔者经过多年的研究与应用，提出了先对井孔进行爆破，然后利用盐酸与二氧化碳联合洗井的综合洗井增水技术，则往往能够取得较好的增水效果．一般增水率在60％以上。该项技术为石灰岩山区小水量的机井的开发提供了技术保证，具有广阔的发展应用前景。 相似文献
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We call attention to the likely importance of the potential reaction OH+ClOHCl+O2. It may only be a minor channel for the reaction of OH with ClO, which is often ignored in models, but if it occurs it considerably increases the rate of recovery of HCl after an air parcel has encountered a polar stratospheric cloud (PSC). The net effect of this reaction on the ozone concentration depends on the relative HCl concentration and whether the air parcel is in a PSC. When an air parcel is in a PSC and the HCl concentration is less than the sum of the HOCl and ClONO2 concentrations, heterogeneous ClO
x
production is rate limited by the production of HCl. Under these conditions the reaction allows HCl to be reprocessed more rapidly by the heterogeneous reactions of HCl with HOCl and ClONO2. This allows high ClO
x
concentration to be maintained for longer, and at a slightly higher level, than would otherwise be possible which in turn leads to more ozone depletion. When there are PSCs but HCl is in excess, or outside of the PSC regions (i.e. during the recovery phase), the reaction will always reduce the ClO/HCl ratio and hence slightly reduce the ozone loss. 相似文献
6.
N. Iwagami S. Ohtsuki K. Tokuda N. Ohira T. Imamura H. Sagawa G.L. Hashimoto M. Ueno S. Okumura 《Planetary and Space Science》2008,56(10):1424-1434
The abundance of hydrogen chloride (HCl) in the Venus atmosphere was measured by ground-based IR spectroscopy. The dayside measurements were performed in May 2007 with a resolution of 40,000, and the nightside measurements in October 1999 with a resolution of 1000. The hemispheric distributions of the HCl mixing ratio measured above the Venus’ clouds show no significant structure with a disc-averaged value of 0.74±0.06 ppm which is in the similar range as the previous report of 0.6±0.2 ppm. The representative height for the dayside measurements is estimated to be 60-66 km. Recent results by Venus Express/SPICAV/SOIR show much smaller values of 0.1-0.2 ppm at 64-94 km; however the direct comparison is difficult due to the different spatial conditions. The hemispheric distributions of the 35Cl/37Cl isotope ratio are also found to show no significant structure with a disc-averaged value of 3.1±0.4 which coincides with the terrestrial value of 3.1. The HCl mixing ratios below the clouds are also found to show no significant structure with a disc-averaged value of 0.40±0.05 ppm, which is similar to the previous reports of 0.4-0.5 ppm. The larger HCl mixing ratio above the clouds than below suggests the production of HCl in the cloud region or above. Also, a uniform hemispherical distribution of H2O is found below the clouds with a disc-averaged mixing ratio of 25±5 ppm; this is in the same range as the previous measurements. Those uniform distributions of HCl and H2O support the fact that their chemical lifetimes are much longer than that of mixing as has been discussed so far. 相似文献
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碳酸盐矿物铁同位素测试的选择性溶解方法包括稀盐酸溶解法和稀醋酸溶解法,已应用于一般地质样品。但是对于白云鄂博矿床这类矿物组成复杂的特殊样品。本文在常温下对白云石、磁铁矿、赤铁矿、黄铁矿、钠闪石和黑云母等白云鄂博矿床中常见的含铁矿物进行稀盐酸(0.5~1 mol/L 盐酸)溶解条件实验。结果显示,稀盐酸在短时间内(约3 h)能够有效地溶解碳酸盐矿物中的铁,而铁氧化物、硫化物、硅酸盐矿物的铁溶解率基本都<1%。实验选取典型的白云鄂博矿床赋矿白云岩,对比了稀盐酸溶解法、稀醋酸溶解法与分离白云石单矿物进行全部溶解所获得的铁同位素组成:赋矿白云岩E-16的δ56Fe值分别为-0.69‰、-0.62‰、-0.69‰;赋矿白云岩E-26的δ56Fe值分别为-0.19‰、-0.18‰、-0.12‰,三种方法在误差(不确定度)范围内结果一致。此外,稀醋酸对碳酸盐的部分溶解过程中没有观察到明显的铁同位素分馏现象,表明稀盐酸溶解法和稀醋酸溶解法都能用于提取白云鄂博矿床样品碳酸盐矿物的铁同位素信息。本研究对于碳酸盐矿物的选择性提取技术在地质上的应用具有借鉴和指导意义。 相似文献
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Florent Dominé Emmanuel Thibert Eric Silvente Michel Legrand Jean-Luc Jaffrezo 《Journal of Atmospheric Chemistry》1995,21(2):165-186
Laboratory and field measurements have been performed in order to improve our understanding of the HCl air-snow transfer function. The solubility and diffusion of HCl in laboratory grown single crystals of ice have been measured as a function of HCl partial pressure,P
HCl, between –8 and –25 °C. Measurements ofP
HCl and of the mole fraction of HCl in snow,X'HCl, have been measured at Summit, Greenland. Comparison of the field and laboratory measurements show that theX'HCl values are well below equilibrium values. The major processes involved in the formation of snow crystals and in their evolution after deposition are discussed in order to attempt to understand theX'HCl values and their variations. The discussion is focussed on a few well identified snow layers. It is concluded that sublimation and recrystallization of snow probably play a major role in the evolution ofX'HCl, but that our understanding of the HCl transfer function is very incomplete. Laboratory and field measurements are suggested to improve this situation. 相似文献
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应用电导法测定了HCl在水和异丙醇混合溶剂中的活度系数,讨论了电解质溶液活度系数与温度和浓度的关系。 相似文献