160 resultados para Line: profiles


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The Grove Mountains, including 64 nunataks, is situated on an area about 3200km2 in the inland ice cap of east Antarctica in Princess Elizabeth land (72o20'-73°101S, 73°50'-75o40'E), between Zhongshan station and Dome A, about 450km away from Zhongshan station (69°22'S, 76°22'E). Many workers thought there was no pedogenesis in the areas because of the less precipitation and extreme lower temperature. However, during the austral summer in 1999-2000, the Chinaer 16 Antarctic expedition teams entered the inland East Antarctica and found three soil spots in the Southern Mount Harding, Grove Mountains, East Antarctica. It is the first case that soils are discovered in the inland in East Antarctica. Interestingly, the soils in this area show clay fraction migration, which is different from other cold desert soils. In addition, several moraine banks are discovered around the Mount Harding. The soil properties are discussed as below. Desert pavement commonly occurs on the three soil site surfaces, which is composed of pebbles and fragments formed slowly in typical desert zone. Many pebbles are subround and variegated. These pebbles are formed by abrasion caused by not only wind and wind selective transportation, but also salt weathering and thaw-freezing action on rocks. The wind blows the boulders and bedrocks with snow grains and small sands. This results in rock disintegration, paved on the soil surface, forming desert pavement, which protects the underground soil from wind-blow. The desert pavement is the typical feature in ice free zone in Antarctica. There developed desert varnish and ventifacts in this area. Rubification is a dominant process in cold desert Antarctic soils. In cold desert soils, rubification results in relatively high concentrations of Fed in soil profile. Stained depth increases progressively with time. The content of Fed is increasing up to surface in each profile. The reddish thin film is observed around the margin of mafic minerals such as biotite, hornblende, and magnetite in parent materials with the microscope analyzing on some soil profiles. So the Fed originates from the weathering of mafic minerals in soils. Accumulations of water-soluble salts, either as discrete horizons or dispersed within the soil, occur in the soil profiles, and the salt encrustations accumulate just beneath surface stones in this area. The results of X-ray diffraction analyses show that the crystalline salts consist of pentahydrite (MgSO4-5H2O), hexahydrite (MgSO4-6H2O), hurlbutite (CaBe2(PO4)2), bloedite (Na2Mg(S04)2-4H2O), et al., being mainly sulfate. The dominant cations in 1:5 soil-water extracts are Mg2+ and Na+, as well as Ca2+ and K+, while the dominant anion is SO42-, then NO3-, Cl- and HCO3-. There are white and yellowish sponge materials covered the stone underside surface, of which the main compounds are quartz (SiO2, 40.75%), rozenite (FeSOKkO, 37.39%), guyanaite (Cr2O3-1.5H2O, 9.30%), and starkeyite (MgSO4-4H2O, 12.56%). 4) The distribution of the clay fraction is related to the maximum content of moisture and salts. Clay fraction migration occurs in the soils, which is different from that of other cold desert soils. X-ray diffraction analyses show that the main clay minerals are illite, smectite, then illite-smectite, little kaolinite and veirniculite. Mica was changed to illite, even to vermiculite by hydration. Illite formed in the initial stage of weathering. The appearance of smectite suggests that it enriched in magnesium, but no strong eluviation, which belongs to cold and arid acid environment. 5) Three soil sites have different moisture. The effect moisture is in the form of little ice in site 1. There is no ice in site 2, and ice-cement horizon is 12 cm below the soil surface in site 3. Salt horizon is 5-10 cm up to the surface in Site 1 and Site 2, while about 26cm in site 3. The differentiation of the active layer and the permafrost are not distinct because of arid climate. The depth of active layer is about 10 cm in this area. Soils and Environment: On the basis of the characteristics of surface rocks, soil colors, horizon differentiation, salt in soils and soil depth, the soils age of the Grove Mountains is 0.5-3.5Ma. No remnants of glaciations are found on the soil sites of Mount Harding, which suggests that the Antarctic glaciations have not reached the soil sites since at least 0.5Ma, and the ice cap was not much higher than present, even during the Last Glacial Maximum. The average altitude of the contact line of level of blue ice and outcrop is 2050m, and the altitude of soil area is 2160m. The relative height deviation is about 110m, so the soils have developed and preserved until today. The parental material of the soils originated from alluvial sedimentary of baserocks nearby. Sporepollen were extracted from the soils, arbor pollen grains are dominant by Pinus and Betula, as well as a small amount Quercus, Juglans, Tilia and Artemisia etc. Judging from the shape and colour, the sporepollen group is likely attributed to Neogene or Pliocene in age. This indicates that there had been a warm period during the Neogene in the Grove Mountains, East Antarctica.

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The Stack Spontaneous Potential (SSP) is a direct hydrocarbon location technology and a new hydrocarbon detection method with independent intellectual property. A subsurface hydrocarbon accumulation associated with the upward hydrocarbon micro seepage induces a relatively strong negative potential abnormal zone, of which the anomaly can be measured on the surface with specially designed instruments through careful field measuring procedures. With special software programmed according to a unique geochemical and geophysical model, the original data are analyzed, processed and interpreted on the computer, and then on a series of resulting anomaly distribution maps and/or profiles, the favorable surface locations of the hydrocarbon accumulations can be easily identified. The study of the SSP has been started since 1989, and especially from 1996 to 1997, both profile and area tests were conducted in the Daqing Oilfield. On the testing line of 15kms, there are 6 wells in total, among which some are oil-producing wells, and some are water-producing wells. The final matching ratio of the favorable oil well locations and the possible water well locations predicted by the SSP to those of known wells was up to 83 percent. In the area test, of which the acreage is 800 km2, the matching ratio compared with the existing wells was 87 percent; furthermore, regarding to wells subsequently drilled after the test, the matching ratio was 85 percent. The matching ratio in the development area is more about 10 percent than those of in exploration area. The reason is that, comparing the exploration area, the development area acreage is less and the container rocks are more simplex. In development area there is not so much interference of SSP also. Since 1997 the SSP has been tested and applied all over China to a number of hydrocarbon bearing basins and known oil fields, including the Daqing, Jiangsu, Changqing, Shengli, Nanyang, Jianghan and Zhongyuan Oilfields, only to name a few. The SSP surveys in total areas of over 10,000km2 in more than 30 regions in China so far have been completed in various exploration and development stages, the satisfactory outcomes of which have further evidenced that the dependence between the SP anomaly and abundance of hydrocarbon. Up to date, a substantial amount of successful tests and actual surveys finished in exploration and development practices have evidenced that the SSP is significantly more reliable in comparison with any other similar direct hydrocarbon indication technique generally known to the oil industry, such as the Redox. The SSP can be applied to search for almost all kinds of hydrocarbon accumulations, regardless of the type of traps, such as structural, stratigraphic, buried hill traps, and so on; however, it is interesting to be noted that the SSP seems to be particularly effective in detecting the stratigraphic oil traps according to our practices. On the other hand, there is virtually no surface geographical constrains in terms of field data acquisition, except for those water covered areas, because of the inherent characteristics of the technology itself. Furthermore, utilizing the SSP requires no special considerations to subsurface geological conditions in regard to formation resistivity, since the SSP measurements will not be influenced by either overly high or overly low resistivity of formations lying above the hydrocarbon accumulations. There are two kind of theory, of which, as we know one is called hypbyssal theory such as "Redox"[61 the other is call plutonic theory such as cracking of hydrocarbon [8][9] and natural polarization [3], to describe the mechanism of SP anomaly of oil reservoir and to indicate that the dependence between the SP abnormality and abundance of hydrocarbon has be existed theoretically/The quantitative dependence, which has not been founded due to the complicity of container rocks, be discovered during the exploration and development practices is the crux to the quantitative analysis of SP Anomaly processing. Based on the thorough study of the complex of collector rocks, every kind of thickness of collector rock can be conversed to be a standard effective thickness; the thickness is called apparent effective thickness (AET). The conversation coefficient (ai, 1=1,2,3) could be determined by the variety of every collector rock storability (CRS). The discoveration of quantitative: dependence between AET and the amplitude of SSP, in the practices of exploration and development, is a promotion for the SSP supplied in the oil exploration, and make the data analysis forward to the quantitative stage.

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Pressurized capillary electrochromatography (pCEC) and electrospray ionization-mass spectrometry (ESI-MS) have been hyphenated for protein analysis. Taken cytochrome c, lysozyme, and insulin as samples, the limits of detection (LODs) for absolute concentrations are 10(-11) mol (signal-to-noise ratio S/N = 3) with relative standard deviations (RSDs) of retention time and peak area, respectively, of less than 1.7% and 4.8%. In order to improve the detection sensitivity, on-line concentration by field-enhanced sample-stacking effect and chromatographic zone-sharpening effect has been developed, and parameters affecting separation and detection, such as pH and electrolyte concentration in the mobile phase, separation voltage, as well as enrichment voltage and time, have been studied systematically. Under the optimized conditions, the LODs of the three proteins could be decreased up to 100-fold. In addition, the feasibility of such techniques has been further demonstrated by the analysis of modified insulins at a concentration of 20 mu g/mL.

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An iminodiacetic acid (IDA)-type adsorbent is prepared at the one end of a capillary by covalently bonding IDA to the monolithic rods of macroporous poly(glycidyl methacrylate-co-ethylene dimethacrylate). Cu(II) is later introduced to the support via the interaction with IDA. By this means, polymer monolithic immobilized metal affinity chromatography (IMAC) materials are prepared. With such a column, IMAC for on-line concentration and capillary electrophoresis (CE) for the subsequent analysis are hyphenated for the analysis of peptides and proteins. The reproducibility of such a column has been proved good with relative standard deviations (RSDs) of dead time of less than 5% for injection-to-injection and 12% for column-to-column (n = 3). Through application on the analysis of standard peptides and real protein samples, such a technique has shown promising in proteome study.