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171.
Possible solar neutron emission associated with five SMM gamma-ray events on 7 June 1980, 21 June 1980, 6 November 1980, 26 November 1982 and 25 April 1984 was found from analysis of 10-minute records of the ground-based neutron monitor at Tokyo. Of these the two events on 21 June 1980 and 25 April 1984 have been already known as neutron events. The time histories of the neutron monitor count rate are compared with those of the gamma-ray count rate and the possibility of energetic neutron emission at the flare site is discussed. 相似文献
172.
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174.
—The Tien-Shan orogene is a region in which the earth’s crust undergoes considerable thickening and tangential compression. Under these conditions the lithosphere heterogeneities (composi tion, rheological) create the prerequisites for the development of various phenomena of tectonic layering (lateral shearing, different deformation of layers). To study the distribution of velocity, density and other elastic parameters, the results from a seismic tomography study on P-wave as well as S-wave velocities were used. Using empirical as well as theoretical formulas on the relationship between velocity, density and silica content in rocks, their distribution in the Tien-Shan’s lithosphere has been calculated. In addition, other elastic parameters, such as Young’s modulus, shear modulus, Poisson’s ratio and coefficient of general compressions have been determined. Zoning of different types of crust was carried out for the region investigated. The characteristics of the "crust-mantle" transition have been investi gated. Large blocks with different types of the earth’s crust were distinguished. Layers with inverse values of velocity, density and shear and Young modulus are revealed in the Tien-Shan lithosphere. All of the above described features open new ways to solve geodynamics problems. 相似文献
175.
William J. Deutsch Kirk J. Cantrell Kenneth M. Krupka Michael L. Lindberg R. Jeffery Serne 《Applied Geochemistry》2011,26(9-10):1681-1693
Residual waste is expected to be left in 177 underground storage tanks after closure at the US Department of Energy’s Hanford Site in Washington State, USA. In the long term, the residual wastes may represent a potential source of contamination to the subsurface environment. Residual materials that cannot be completely removed during the tank closure process are being studied to identify and characterize the solid phases and estimate the release of contaminants from these solids to water that might enter the closed tanks in the future. As of the end of 2009, residual waste from five tanks has been evaluated. Residual wastes from adjacent tanks C-202 and C-203 have high U concentrations of 24 and 59 wt.%, respectively, while residual wastes from nearby tanks C-103 and C-106 have low U concentrations of 0.4 and 0.03 wt.%, respectively. Aluminum concentrations are high (8.2–29.1 wt.%) in some tanks (C-103, C-106, and S-112) and relatively low (<1.5 wt.%) in other tanks (C-202 and C-203). Gibbsite is a common mineral in tanks with high Al concentrations, while non-crystalline U–Na–C–O–P ± H phases are common in the U-rich residual wastes from tanks C-202 and C-203. Iron oxides/hydroxides have been identified in all residual waste samples studied to date. Contaminant release from the residual wastes was studied by conducting batch leach tests using distilled deionized water, a Ca(OH)2-saturated solution, or a CaCO3-saturated water. Uranium release concentrations are highly dependent on waste and leachant compositions with dissolved U concentrations one or two orders of magnitude higher in the tests with high U residual wastes, and also higher when leached with the CaCO3-saturated solution than with the Ca(OH)2-saturated solution. Technetium leachability is not as strongly dependent on the concentration of Tc in the waste, and it appears to be slightly more leachable by the Ca(OH)2-saturated solution than by the CaCO3-saturated solution. In general, Tc is much less leachable (<10 wt.% of the available mass in the waste) than previously predicted. This may be due to the coprecipitation of trace concentrations of Tc in relatively insoluble phases such as Fe oxide/hydroxide solids. 相似文献
176.
177.
DNA from five tumors, three other-injured livers and two normal liver tissue samples from the European flounder were analyzed for mutations in exons 5-8 of the tumor suppressor gene p53 and at codons 12, 13 and 61 of Ha- and Ki-ras proto-oncogenes. No tumor-specific mutations were identified by direct sequencing and single-strand conformation polymorphism of these genes. A number of silent polymorphisms were noted in p53. In addition to a need for more extensive analyses of flounder liver tumor samples for ras or p53 mutations, other cancer-related genes should be investigated. 相似文献
178.
The soft X-ray emission of the solar corona is investigated by comparison of the signals of several broad band photometers carried on the Solrad 9 satellite, and sensitive to the region 0.5–20 Å. Temperature from 1.5 × 106 to 25 × 106 K have been measured with emission measure N
e
2 dV ranging between 1050 cm–3 to 1047 cm–3.By means of the observational data and assuming magnetic confinement and hydrostatic equilibrium, the model of an active region is investigated. For temperatures larger than 107K the emission is due to flare activity and two sets of emission measure are observed which appear to be related to the evolution of flares. 相似文献
179.
On entropy and clustering in earthquake hypocentre distributions 总被引:3,自引:0,他引:3
180.
Summary The change of rainfall totals with height has been the subject of much investigation in many parts of the world. The rates of increase or decrease vary with the climatic regime experienced. This study of Sri Lankan rainfall shows that the relationship between height and mean annual rainfall is complex. Examples of increases and decreases of rainfall with height are found. The climatic regime of the area is important in controlling the level of maximum rainfall.With 7 Figures 相似文献