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Carbon isotopic fractionation during the air/sea exchange process is not fully understood at present. Information on the equilibrium and kinetic fractionation factors is an essential requirement, together with the value of the CO2 partial pressure, for understanding the carbon cycle in the atmosphere and marine environments. Using a specially designed countercurrent equilibrator system, the fractionation factors between gaseous CO2 and dissolved inorganic carbon in sea water were determined under both kinetic and equilibrium conditions. The following results were obtained: kinetic fractionation factor for air to sea (αas) is 0.998 at 288.2 K; kinetic fractionation factor for sea to air (αsa) is 0.990; equilibrium fractionation factor (αeq) is 0.991 at pH = 8.3 and 288.2 K. From these results, the carbon isotopic ratio of CO2 passed through the air/ sea interface is estimated to be about ?10 %. for air to sea and ?8 %. for sea to air when CO2 exchange takes place between air (δ13C = ?8 %.) and surface sea water (δ13C = 2 %.) at 288.2 K. 相似文献
13.
Kazutaka Yamaoka Yoshihiro Ueda Hajime Inoue Fumiaki Nagase Ken Ebisawa Taro Kotani Yasuo Tanaka 《Astrophysics and Space Science》2001,276(1):19-22
We summarize the ASCA observations of the two Galactic superluminal sources GRO J1655–40 and GRS 1915+105, focusing on theabsorption line features.The high spectroscopic capability of ASCA enabled us to detectiron-K absorption line features from both objects. This is direct evidence for the presence of highly ionized plasma in a non-spherical configuration around a black hole, and is considered to be a unique signature of superluminal jet systems. The candidate of the line-absorber would be a part of an accretion disk at a distance of 109-11 cm from the central X-ray source. 相似文献
14.
The crystal structure of hydrous wadsleyite, Mg1.75SiH0.5O4 synthesized in an MA 8-type apparatus at conditions of 1300°C and 15.5 GPa, has been analyzed and refined in space group Imma, using the X-ray intensities measured on a 60X60X10 μm single crystal. The composition (Z=8) and unit cell are Mg1.74Si0.97H0.65O4 by E.P.M.A. analysis and a=5.663(1) Å, b= 11.546(2) Å, c=8.247(4) Å, V=539.2(5) Å3. The partial M-site occupancies were determined; vacancies associated with the incorporation of water are strongly concentrated on the Mg 3 site. The OH in the structure was confirmed by Raman and FTIR spectroscopies. The result of valence sum calculation based on the refined bond lengths indicates that O1 is a hydroxyl. The formula of hydrous wadsleyite can be expressed as Mg2-xSiH2xO4, where 0≤x≤0.25. When x=0.25, all of the O1 site is hydroxyl and the maximum solubility of 3.3 wt% H2O is realized. Structural relations to other dense hydrous phases are discussed. 相似文献
15.
Wataru Ootani Makoto Minowa Takayuki Watanabe Yutaka Ito Yasuhiro Kishimoto Kentaro Miuchi Yoshizumi Inoue Youiti Ootuka 《Astroparticle Physics》1998,9(4):325-329
The performance of a 21-g lithium fluoride bolometer is presented. The background spectrum was measured in the surface laboratory. We derive an exclusion plot for the spin-dependent coupled Weakly Interacting Massive Particles (WIMPs) cross section. 相似文献
16.
The10Be method of dating of marine sediment cores is applied to five North Pacific cores. Assuming a constant10Be precipitation rate and varying sedimentation rates with time during the past 2.5 m.y. dating confirms to that obtained from paleomagnetic stratigraphy. The10Be concentration variations with depth in the cores are primarily due to changes in sediment dilution and do not reflect cosmic ray intensity or global climate variations. The limits of10Be deposition rate variation in the investigated cores are less than ± 10% for periods of (2–7) × 105 years and less than ±30% for periods of 1 × 105 years. The data set gives a half-life of10Be is 1.50 × 106 years. The latitudinal effect of10Be concentrations and10Be/9Be ratios relates to a frequency of particulate matter occurrence (detrital and biological particles) in the oceans and to oceanic circulation. 相似文献
17.
The depth profile of the long-lived radionuclide10Be in a marine sediment recovered in the vicinity of the Samoan Islands has been precisely assayed with a highly sensitive needle-type gas counter. The obtained irregular pattern of10Be concentrations with depths ranging from 4.7 to 0.3 dpm/kg dry sediment is interpreted as being due to dilution of10Be by volcanic eruptions in the past. 相似文献
18.
Eiichi Inoue 《Boundary-Layer Meteorology》1974,7(3):257-266
A brief review of the research activities of Japanese scientists in aerobiology, which is one of the interdisciplinary sciences closely related to atmospheric turbulence and diffusion as well as to biology, is presented in order to make contacts with interested scientists in other countries. 相似文献
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20.
Application of Chlorite Geothermometry to Hydrothermal Alteration in Toyoha Geothermal System, Southwestern Hokkaido, Japan 总被引:1,自引:0,他引:1
In this study, we applied chemical geothermometers to the estimation of formation temperatures of chlorites from various types of hydrothermally altered rocks in the Toyoha geothermal field, using core samples from six drill holes (TH-2 to TH-7) together with wasted ore samples from Toyoha vein-type ore deposit. Based on the preliminary examination of mineral assemblages by X-ray powder diffraction and optical microscopy, hydrothermal alteration observed through the drill holes was classified into four types of alteration zones: propylitic, mixed-layer minerals, kaolin minerals, and ore mineralized zones. The mineral assemblage of the ore mineralized zone observed through TH-2, TH-4, and TH-6 is similar to those of Toyoha ore veins reported previously. The Fe3+/ΣFe ratios of chlorites were determined by X-ray photoelectron spectroscopy (XPS), in addition to the usual microprobe analyses. The ratios ranged from 0.20–0.26 for chlorites from the propylitic alteration zone and from 0.13 to 0.17 for those from the ore mineralized zone associated with sulfide minerals. After correcting the Fe3+ contents in the octahedral sites of chlorite structures, we obtained acceptable temperatures of the chlorite formation by application of geothermometers, for instance, a similar range of 150–300°C for chlorites from either the propylitic zone or the ore mineralized zone developed through TH-2, TH-4, and TH-6. Chlorites from the ore mineralized zone proximal to the Toyoha deposit are characterized by high Fe and Mn contents compared to the propylitic chlorites, which is similar to the Toyoha vein-filling chlorites; the formation temperatures were close to both the homogenization temperatures of fluid inclusions and the present subsurface temperatures measured through drill holes. Chlorites from the Toyoha ore veins, however, gave slightly higher formation temperatures (180–350°C) than those of chlorites from the ore mineralized zone in the drill cores. This suggests that several types of hydrothermal alteration occurred at different stages in the Toyoha geothermal field and the composition of product chlorite was controlled not only by the temperature but also the composition of fluid related to the formation. Reliable estimation of temperature for the chlorite formation provides basic information on evaluating correctly other physicochemical conditions prevalent at the formation. 相似文献