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1.
E. F. Mikhailov S. S. Vlasenko T. I. Ryshkevich 《Izvestiya Atmospheric and Oceanic Physics》2008,44(4):416-431
The hygroscopic properties of a model smoke aerosol series including ammonium sulfate, levoglucosan, and oxalic and humic acids were investigated. The condensation growth of particles and the relative humidity of direct and inverse particle-droplet phase transitions were measured with a tandem differential mobility analyzer. The data were obtained in the range of relative humidity from 4 to 95% at 298 K. Experimental growth factors were compared to the results of Koehler theory by using contemporary models of water activity in particles. It was shown that the hygroscopic properties of the aerosols were substantially different from the hygroscopic properties of the corresponding bulk phases. It was found that a complex microstructure of nanoparticles resulted in excess volume absorption of water, in some cases causing their full deliquescence at lower relative humidities than in macrosystems of identical composition. From the measurement data, a parametrization of hygroscopic particle growth was performed. The results of parametrization can be used to construct refined models of a smoke aerosol. 相似文献
2.
L. P. Golobokova V. E. Pavlov I. V. Khvostov T. V. Khodjer 《Izvestiya Atmospheric and Oceanic Physics》2011,47(3):329-335
We consider the resemblance between the ion composition of the fraction of soluble aerosols and gaseous admixtures in the atmospheric surface layer at the high-level Mondy station (East Sayan), those in the Listvyanka settlement south of Lake Baikal, in the city of Irkutsk, and at the Primorskaya station near the city of Ussuriysk (Primorskii krai). We use measurement data on the concentrations of the following ions: HCO 3 ? , SO 4 2? , NO 3 ? , Cl?, H+, Na+, K+, Mg2+, Ca2+ in the soluble fraction of aerosols and gases HNO3, HCl, NH3, and SO2 in air samples over a 10-year period conducted in the mode of online monitoring. We found the lognormal form of distributions of concentrations of each of the abovementioned components according to the number of samples. A versatile scheme of the distribution of mean geometric concentrations of atmospheric components was proposed for all four groups. 相似文献
3.
Chunfang Cai Zengye Xie Richard H. Worden Guoyi Hu Lansheng Wang Hong He 《Marine and Petroleum Geology》2004,21(10):1265-1279
New sour pools have recently found in the Lower Triassic Feixianguan Fm carbonate reservoirs in the East Sichuan Basin in China with H2S up to 17.4% by volume. A recent blowout from a well drilled into this formation killed hundreds of people as a result of the percentage concentrations of H2S. In order to assess the origin of fatal H2S as well as the cause of petroleum alteration, H2S concentrations and the isotopes, δ34S and δ13C have been collected and measured in gas samples from reservoirs. Anhydrite, pyrite and elemental sulphur δ34S values have been measured for comparison. The high concentrations of H2S gas are found to occur at depths >3000 m (temperature now at 100 °C) in evaporated platform facies oolitic dolomite or limestone that contains anhydrite nodule occurrence within the reservoirs. Where H2S concentrations are greater than 10% its δ34S values lie between +12.0 and +13.2‰ CDT. This is within the range of anhydrite δ34S values found within the Feixianguan Fm (+11.0 to +21.7‰; average 15.5±3.5‰ CDT). Thus H2S must have been generated by thermochemical sulphate reduction (TSR) locally within the reservoirs. Burial history analysis and fluid inclusion data reveal that the temperature at which TSR occurred was greater than about 130–140 °C, suggesting that the present depth-temperature minimum is an artifact of post-TSR uplift. Both methane and ethane were actively involved in TSR since the petroleum became almost totally dry (no alkanes except methane) and methane δ13C values become significantly heavier as TSR proceeded. Methane δ13C difference thus reflects the extent of TSR. While it is tempting to use a present-day depth control (>3000 m) to predict the distribution of H2S in the Feixianguan Fm, this is an invalid approach since TSR occurred when the formation was buried some 1000–2000 m deeper than it is at present. The likelihood of differential uplift across the basin means that it is important to develop a basinal understanding of the thermal history of the Feixianguan Fm so that it is possible to determine which parts of the basin have been hotter than 130–140 °C. 相似文献
4.
Structure and seasonal variability of the deep mean circulation of the East Sea (Sea of Japan) 总被引:1,自引:0,他引:1
The horizontal structure of deep mean circulation and its seasonal variability in the Japan/East Sea (JES) were studied using
profiling float and moored current meter data. The deep circulation in the Japan Basin (JB) flows cyclonically, basically
following f/H contours. The correlation between the directions of deep current and f/H contour increases as |▿(f/H)| increases, reaching remarkably high correlation coefficient (>0.8) values in steep slope regions in the JB. In contrast
to the JB, the deep mean circulation in the Ulleung/Tsushima Basin (UTB) is generally weak and cyclonic accompanied by sub-basin-scale
cyclonic and anticyclonic eddies. The UTB shows a poorer correlation between directions of deep current and f/H contours than other basins. The time-space averaged deep mean current is about 2.8 cm/s and the volume transport in the deep
layer (800 m to bottom) in the JB reaches about 10 Sv (10 × 106 m3s−1), which is about four times greater than the inflow transport through the Tsushima Straits. A salient feature is that the
amplitude of deep mean current in the JB reveals a remarkable seasonal variation with a maximum in March and minimum in October.
The annual range of the seasonal variation is about 30% of the mean velocity, whereas that in the southern JES (UTB and Yamato
Basin) is weak. 相似文献
5.
A. N. Yermakov A. E. Aloyan T. V. Khodzer L. P. Golobokova V. O. Arutyunyan 《Izvestiya Atmospheric and Oceanic Physics》2007,43(2):208-218
Monitoring data on the ion composition of aerosols and gas admixtures in the background and polluted atmosphere of the Lake Baikal region are presented. The ion composition and morphology of aerosols are affected by heterogeneous chemical reactions and variations in relative humidity. Two types of aerosol particles are revealed over this region. The fraction of solid particles recorded in most episodes includes primarily carbonates of alkaline and alkaline-earth metals. With increased atmospheric humidity, these particles are engaged in heterogeneous chemical reactions with gas-phase NH3 and H2SO4, proceeding through the phase of watering. As a result, the composition of these aerosols is changed, and a fraction of aqueous H2O/H2SO4/(NH4)2SO4 aerosol particles of a different composition is formed. On the basis of a physical and chemical analysis of monitoring data on the aerosol composition and concentrations of gas admixtures, the average aerosol-size distribution of different types is estimated. For the first time, the mean acidity of aqueous aerosol particles is estimated. 相似文献
6.
The hydrolysis of silicic acid, Si(OH)4, was studied in a simplified seawater medium (0.6 M Na(Cl)) at 25°C. The measurements were performed as potentiometric titrations (hydrogen electrode) in which OH− was generated coulometrically. The total concentration of Si(OH)4, B, and log[H+] were varied within the limits 0.00075 B 0.008 M and 2.5 -log[H+] 11.7, respectively. Within these ranges the formation of SiO(OH)3− and SiO2(OH)22− with formation constants log β−11(Si(OH)4 SiO(OH)3− + H+) = −9.472 ±0.002 and log β−21(Si(OH)4 SiO2(OH)22− + 2H+) = −22.07 ± 0.01 was established. With B > 0.003 M polysilicate complexes are formed, however, with -log[H+] 10.7 their formation does not significantly affect the evaluated formation constants. Data were analyzed with the least squares computer program LETAGROPVRID. 相似文献
7.
The rates of the reduction of Cr(VI) with S(IV) were measured in deaerated NaCl solution as a function of pH, temperature and ionic strength. The rates of the reaction were found to be first order with respect to Cr(VI) and second order with respect to S(IV), in agreement with previous results obtained at concentrations two order higher than the present study. The reaction also showed a first-order dependence of the rates on the concentration of the proton and a small influence of temperature with an apparent energy of activation ΔHapp of 22.8 ± 3.4 kJ/mol. The rates were independent of ionic strength from 0.01 to 1 M. The rate of Cr(VI) reduction is described by the general expression
−d[Cr(VI)]/dt=k[Cr(VI)][S(IV)]2