Relative concentration of oxygen atoms and molecules at a height of 120 km according to the data of ionospheric measurements

It is convenient to use the semi-empirical model (SEM), developed by the authors earlier and describing the relation of the electron density at heights of the middle ionosphere (120–200 km) to the parameters of the thermosphere and the integral flux of the ionizing solar radiation, to estimate the gas composition characteristics using the data of ionospheric measurements [Shchepkin et al., 2008]. The ratios of the concentrations of oxygen atoms and nitrogen molecules to those of oxygen molecules and atoms at a height of 120 km are compared using two SEM versions. The first version is based on the usage of the coefficients obtained from the measurements of N(h) profiles at Moscow observatory. The electron densities at heights of 120–200 km, obtained at the Institute of Solar-Terrestrial Physics in 2003–2006 using the digisonde, were the experimental data for the second version.     

Determination of O2(a1 delta g) and O2(b1 sigma+ g) yields in the reaction O + ClO --> Cl + O2: implications for photochemistry in the atmosphere of Venus

A discharge flow apparatus with chemiluminescence detector has been used to study the reaction O + ClO --> Cl + O2, where O2 = O2(a1 delta g) or O2(b1 sigma+ g). The measured quantum yields for producing O2(a1 delta g) and O2(b1 sigma+ g) in the above reaction are less than 2.5 x 10(-2) and equal to (4.4 +/- 1.1) x 10(-4), respectively. The observed O2(a1 delta g) airglow of Venus cannot be explained in the context of standard photochemistry using our experimental results and those reported in recent literature. The possibility of an alternative source of O atoms derived from SO2 photolysis in the mesosphere of Venus is suggested.     

武山1号泉流量、O_2+Ar、N_2、He的异常变化分析

对武山台1号泉气体资料显示,在1997-1999、2003年流量有几次明显的突变,同时气体组分O2 Ar、N2、He百分含量与流量呈完全同步变化.本文分析了造成流量突变的原因,认为流量大幅度变化不是自然动态的.同时用试验方法验证了影响气体组分O2 Ar、N2、He百分含量变化的主要因素是流量、冲流时间和空气混入了泉水,并分析了它们之间的相互关系及变化特点.     

The mobility spectrum and the ion concentration of large ions in air mixed with N2O gas

Summary Using the divided electrode condenser it was possible to detect the large ion groups formed when small amounts of N₂O gas were mixed with atmospheric air. Eight groups appeared with mobilities ranging from 12.50×10^–4 to 0.60×10^–4 cm/sec: volt/cm. When using the whole electrode condenser the results showed an increase in the total ion concentration of these large ions when small amounts of N₂O gas were mixed with air. The results obtained in this work confirm that N₂O gas acts as a nucleus for condensation which is changed into a large ion by appropriating an electrical charge.     

Solubility of gold in the SiO2-NaCl-H2O system at 300°C and50 MPa

The solubility of gold and quartz in 0.01, 0.10 and 1. 00 mol/kg NaCl solutions with various pH was determined in the presence of the NNO oxygen buffer at 300°C and 50 MPa using a flexible gold cell hydrothermal apparatus. The Au speciation in the SiO₂-NaCI-H₂O system was inferred and the equilibrium constants for the following dissolution reactions were obtained: Au+H₂O = AuOH⁰+1/2H₂, logK(AuOH⁰) = -7.92 ± 0.25; Au+Cl^-+H₂O = AuOHCl^-+1/2H₂, logK(AuOHCl^-) = - 7. 56 ± 0.65. The present study suggests that Au as AUOH⁰ and AuOHCl^- is basically transported in ore-forming solutions under geologically realistic conditions of acidity, chloride molality and oxygen fugacity. The reason for the common association of Au with SiO₂ in hydrothermal gold deposits is discussed. Project supported hy the National Natural Science Foundation of China.     

Proton transport model in the ionosphere. 2. Influence of magnetic mirroring and collisions on the angular redistribution in a proton beam

We investigate the influence of magnetic mirroring and elastic and inelastic scattering on the angular redistribution in a proton/hydrogen beam by using a transport code in comparison with observations. H-emission Doppler profiles viewed in the magnetic zenith exhibit a red-shifted component which is indicative of upward fluxes. In order to determine the origin of this red shift, we evaluate the influence of two angular redistribution sources which are included in our proton/hydrogen transport model. Even though it generates an upward flux, the redistribution due to magnetic mirroring effect is not sufficient to explain the red shift. On the other hand, the collisional angular scattering induces a much more significant red shift in the lower atmosphere. The red shift due to collisions is produced by < 1 -keV protons and is so small as to require an instrumental bandwidth <0.2nm. This explains the absence of measured upward proton/hydrogen fluxes in the Proton I rocket data because no useable data concerning protons < 1 keV are available. At the same time, our model agrees with measured ground-based H-emission Doppler profiles and suggests that previously reported red shift observations were due mostly to instrumental bandwidth broadening of the profile. Our results suggest that Doppler profile measurements with higher spectral resolution may enable us to quantify better the angular scattering in proton aurora.     

Diffusion in magmas at depth in the Earth: The effects of pressure and dissolved H2O

Experimental data on cation diffusion in silicate melts and glasses at atmospheric pressure cannot be quantitatively applied to diffusion in magmas at depth because pressure and dissolved H₂O have significant effects. Diffusivities of Ca and Cs in soda-lime aluminosilicate melt are reduced by roughly an order of magnitude as pressure increases from 1 to 30 kbar at 1100°C (in the case of calcium, the pressure effect is smaller at higher temperatures). The influence of dissolved H₂O is opposite to and (for some ions) far more important than that of pressure: at 700°C, Cs diffusion in granitic obsidian is enhanced by four orders of magnitude by the addition of 6 wt.% H₂O, and Ca diffusivity increases by 2.5 orders of magnitude. Sodium diffusion, on the other hand, is relatively immune to changes in H₂O content.The retarding effect of pressure on diffusion in deep-seated magmas is largely compensated by higher magmatic temperatures, such that overall “depth” effects on diffusion are of secondary importance — diffusion rates in mantle melts are probably well approximated by 1-atm, near-liquidus values. Diffusion rates in crustal magmas, however, are extremely sensitive to H₂O content, so that models of rate-controlled processes in hydrous magmas may be grossly in error if 1-atm diffusivity values are used.     

Results of concentration and mobility measurements of positively and negatively charged particles taken by a rocket-borne parachuted aspiration (Gerdien) probe in the height region from 72 to 39 km

Summary With a self-neutralizing, rocket-borne parachute aspiration probe concentration and mobility measurements of positively and negatively charged carriers were made between 72 and 40 km over Sardinia. Between 72 km and 60 km a heavy and a light group of positively charged particles were found. The heavy group was more abundant than the hight group in the greater heights. For the negatively charged particles only one mobility group was found which roughly corresponded to the mobility of the light group of the positively charged carriers. The probe was designed so that no electrons could enter the analyzer section of the aspiration system. By this the electron concentration was given by the difference in concentration between the positively and negatively charged particles.This paper was read byH. Dolezalek, in an abbreviated form supplied by the authors.     

Distribution of the concentration at small and large distances from a steady line source in the surface layer under unstable stratification

Summary The solution about the concentration from a line source in the surface layer under unstable stratification obtained by us in [1]² is investigated. A physical sense is given to the obtained simple asymptotic representations, determining on the basis of some numerical calculations the region of their applicability too.     

Linear mechanism of generation and intencification of internal gravity waves in the ionosphere at their interaction with a nonuniform zonal wind: 1. Model of the medium and initial dynamic equations

The specific features of the generation and intensification of internal gravity wave structures in different atmospheric-ionospheric regions, caused by zonal local nonuniform winds (shear flows), are studied. The model of the medium has been explained and an initial closed system of equations has been obtained in order to study the linear and nonlinear dynamics of internal gravity waves (IGWs) when they interact with the geomagnetic field in a dissipative ionosphere (for the D, E, and F regions).     

Impacts of nutrient management and decrease in paddy field area on groundwater nitrate concentration: a case study at the Nasunogahara alluvial fan,Tochigi Prefecture,Japan

In order to help evaluate the trends in the NO₃-N concentration in groundwater with a view to preventing further degradation in water quality in the future, a distributed groundwater quality model was constructed for the Nasunogahara basin. The best fit for the groundwater table elevations by the flow component of the model was achieved with average mean absolute errors (MAEs) of 0·92 m for the calibration period and 0·83 m for the validation period. Moreover, the best fit for the NO₃-N concentration by the water quality component was achieved with average mean relative errors (MREs) of 29·8% for the calibration period and 30·3% for the validation period. After developing a robust model, various change scenarios were tested; specifically, the effects of effluent load control and a decrease in paddy field area on the NO₃-N concentration in groundwater were predicted. The most intensively farmed area contributed about 40% of the total effluent load because of livestock farming in the basin. When the effluent load from this area was decreased by 50%, the average NO₃-N concentrations at sites S1, S2 and S3 were reduced by about 15%; however, the average concentrations at S4 and S5 were reduced by only 1%. Furthermore, when the total effluent load from the concentrated livestock area was removed completely, the average groundwater NO₃-N concentrations at S1, S2 and S3 were reduced by about 30% as compared with the original calculated results. In contrast, decreasing the area of the paddy fields in the basin did not greatly influence the groundwater NO₃-N concentration. In the case of a 70% reduction in paddy field area, average NO₃-N concentrations increased by about 7% at S1, S2 and S3. Copyright © 2008 John Wiley & Sons, Ltd.     

Iron ions Fe<Superscript>2+</Superscript> and Fe<Superscript>3+</Superscript> in a magnetic model of the sedimentary medium

The concentration of rock-forming elements, the static magnetic susceptibility κ, spectra of electron paramagnetic resonance, and their relative intensities I are studied in samples from a borehole drilled in Cenozoic sedimentary deposits of southern Western Siberia. All measured values experience appreciable irregular variations with depth. A linear dependence exists between κ and I within the range of their medium and large values; κ and I have maximum values in the same sample, and κ_max = 1920 × 10^?6SI, κ_min = 210 × 10^?6 SI, and κ_av = 630 × 10^?6 SI. The magnetic properties of the samples are controlled by Fe²⁺ ions present in clastic material and by microphases (clusters) with Fe³⁺ ions of the goethite and lepidocrocite type present in the cement. The theoretically possible magnetic susceptibility of the Fe²⁺ ion system (provided that all iron exists in this form) is quite comparable with κ_min but, even with very high concentrations of Fe²⁺, does not reach half of κ_av: (154 < κ(Fe²⁺) < 254) × 10^?6 SI. Anomalously high values of κ are due to a large number of clusters with Fe³⁺ ions if structural units FeOOH do not dissociate and the interaction of the clusters with hydroxides of aluminum and precipitation medium impedes the process of their coagulation. Otherwise, the cluster sizes gradually increase, an antiferromagnetic structure develops in clusters, and the magnetic susceptibility decreases.     

Modeling the dynamics of a plasma bulge with a high specific energy in the upper atmosphere. 2. Numerical simulation and physical features of a large-scale plasma flow at its late development stage: A review

The results of three-dimensional calculations of a plasma flow caused by a cosmic nuclear explosion, performed in an MHD approximation, are presented. The main regularities and specific features of the development of a large-scale plasma flow have been analyzed for a later stage (up to several hundreds of seconds) depending on the altitude and plasma bulge energy.     

Disturbances in the <Emphasis Type="Italic">F</Emphasis>2 region critical frequency before the earthquake of September 11, 2008 off the coast of Hokkaido,Japan, and during a moderate magnetic storm based on data from ground-based vertical ionosphere sounding stations

Based on data from ground-based vertical sounding stations, the behaviors of the ionosphere F region before a strong M 6.8 earthquake off the coast of Hokkaido, Japan, and during the moderate magnetic storm before this earthquake are compared. It was found that the critical frequency of the ionosphere F region (foF2) above the Wakkanai ground-based ionosphere vertical sounding station, which was located in the preparation zone of this earthquake, suffered a long-term disturbance of slightly more than an hour nearly half a day before the earthquake. The magnitude of earthquake-induced disturbance is comparable to that caused by a magnetic storm.