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951.
风火山地区西金乌兰湖-金沙江蛇绿构造混杂带的物质组成及发展演化特征 总被引:3,自引:0,他引:3
笔者以构造地质调查为主线,以蛇绿构造混杂带建造为基础,通过路线地质调查,剖而测制工作,在全面收集岩石学、岩石化学、年代学、地球化学、运动学等资料的基础上,重点对西金乌兰湖-金沙江蛇绿构造混杂带的物质组成、规模、边界断裂特征等的研究,进而恢复和再造缝合带的发展演化历史。对缝合带的物质组成进行全方位解剖。在综合缝合带组成,结构、构造等方面的基础上对其形成、发展演化进行探讨和研究。为青藏高原及东特提斯超级造山系统的研究提供一定的依据。 相似文献
952.
A. S. Astakhov V. V. Sattarova A. I. Svininnikov N. V. Astakhova M. M. Domanov M. V. Ivanov 《Russian Journal of Pacific Geology》2007,1(5):418-434
This paper reports the results of an investigation of the chemical composition and distribution of manganese-rich metalliferous sediments in the Deryugin Basin. They compose an upper sedimentary layer up to 30 cm thick within a strip up to 40 km wide and 180 km long in the central part of the basin along the East Deryugin suture zone bounding the Deryugin sedimentary basin to the east. The sediments are enriched relative to the regional background composition in Mn (by a factor of 35); Au; Ni; Zn; Co (by a factor of 3–5); and, locally, in Mo, V, Ba, Cu, Pb, and Hg. It was supposed that their formation was controlled by several processes: precipitation of Mn and some other trace elements from hydrothermal plumes of seawater that occasionally form above submarine hot vents in the northern part of the basin, precipitation from anoxic bottom waters at the eastern boundary of the Deryugin sedimentary basin, and early diagenetic migration of Mn into the surface sediments. 相似文献
953.
B. Demirdjian D. Ferry J. Suzanne O. B. Popovicheva N. M. Persiantseva N. K. Shonija 《Journal of Atmospheric Chemistry》2007,56(1):83-103
Size, morphology, microstructure, chemical composition and hygroscopic properties of aircraft engine combustor (AEC) soot particles are studied by using a combination of several methods, namely atomic force microscopy, transmission electron microscopy, gravimetry, ionic chromatography analysis and wetting observations. From the microstructure and the composition of soot agglomerates, we find that we can separate AEC soot in two fractions having quite different physico-chemical properties: a main fraction of particles containing essentially amorphous carbon with small amounts of oxygen, sulfur and iron and a fraction of impurities characterized by various structures and a large amount of impurities. These properties of aircraft engine combustor soot are compared to those of soot obtained by burning TC1 aviation kerosene in a laboratory burner. It is shown that TC1 soot can be a good surrogate of the AEC main fraction. Such a finding allows us to perform water uptake measurements and to conclude that the AEC main fraction is rather hydrophobic whereas the AEC fraction of impurities is highly hydrophilic The ability of the two fractions of aircraft engine combustor soot to act as cloud condensation nuclei is discussed with respect to their implication in contrail and cirrus formation.Associated to Université de la Méditerranée (Aix-Marseille II) and to Université Paul Cézanne (Aix-Marseille III) 相似文献
954.
K. Slezakova M. C. Pereira M. A. Reis M. C. Alvim-Ferraz 《Journal of Atmospheric Chemistry》2007,58(1):55-68
Epidemiological studies initially considered the impact of total solid particles on human health, but according to the acquired
knowledge about the worse effect of smaller particles, those studies turned to consider the impact of PM10. However, for the last decade PM2.5 began to be more important, once as they are smaller they can penetrate deeper in the lungs, being possible their trapping
in alveoli and worse effects on human health. Therefore, more information on PM2.5 should be provided namely concerning the levels and elemental composition. Considering the relevance of traffic on the emission
of particles of small sizes, this work included the detailed characterization of PM10 and PM2.5, sampled at two sites directly influenced by traffic, as well as at two reference sites, aiming a further evaluation of the
influence of PM10 and PM2.5 on public health. The specific objectives were to study the influence of traffic emission on PM10 and PM2.5 characteristics, considering concentration, size distribution and elemental composition. PM10 and PM2.5 samples were collected using low-volume samplers; the element analyses were performed by particle induced X-ray emission
(PIXE). At the sites influenced by traffic emissions PM10 and PM2.5 concentrations were 7–9 and 6–7 times higher than at the background sites. The presence of 17 elements (Mg, Al, Si, P, S,
Cl, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn and Pb) was determined in both PM fractions; particle metal contents were 3–44 and
3–27 times higher for PM10 and PM2.5, respectively, than at the backgrounds sites. The elements originated mostly from anthropogenic activities (S, K, V, Mn,
Ni, Zn and Pb) were predominantly present in PM2.5, while the elements mostly originated from crust (Mg, Al, Si and Ca) predominantly occurred in PM2.5–10. The results also showed that in coastal areas sea salt spray is an important source of particles, influencing PM concentration
and distributions (PM10 increased by 46%, PM2.5/PM10 decreased by 26%), as well as PM compositions (Cl in PM10 was 11 times higher). 相似文献
955.
956.
Relations of Rock Structure and Composition to Petrophysical and Geomechanical Rock Properties: Examples from Permocarboniferous Red-Beds 总被引:2,自引:0,他引:2
Summary. This study relates textural properties to physical and mechanical properties of coarse grained sedimentary rocks of Permocarboniferous age. As an equivalent to rock texture the principle of geomechanical order is applied. The geomechanical order describes a rock as a function of its structural and compositional order which are derived from petrological analyses. Our results indicate that rock properties like density and porosity are stronger dependent on the structural order, while strength properties additionally depend on the compositional order. The ultrasonic wave velocity responds to both structural and compositional properties. These evidences imply that the geomechanical order is not an independent parameter but a variable function of structural or compositional features, which needs specification for correlation purposes to distinct physical and mechanical rock properties. 相似文献
957.
The spectral irradiance at the center of the solar H I Lyman α (, referred to as Lyα in this paper) line profile is the main excitation source responsible for the atomic hydrogen resonant scattering of cool material in our Solar System. It has therefore to be known with the best possible accuracy in order to model the various Lyα emissions taking place in planetary, cometary, and interplanetary environments. Since the only permanently monitored solar irradiance is the total one (i.e. integrated over the whole Lyα line profile), Vidal-Madjar [1975. Evolution of the solar Lyman alpha flux during four consecutive years. Solar Phys. 40, 69-86] using Orbiting Solar Observatory 5 (OSO-5) satellite Lyα data, established a semi-empirical formula allowing him to deduce the central spectral Lyα irradiance from the total one. This relation has been extensively used for three decades. But, at the low altitude of the OSO-5 orbit, the central part of the solar line profile was deeply absorbed by a large column of exospheric atomic hydrogen. Consequently, the spectral irradiance at the center of the line was obtained by a complex procedure confronting the observations with simulations of both the geocoronal absorption and the self-reversed shape of the solar Lyα profile. The SUMER spectrometer onboard SOHO positioned well outside the hydrogen geocorona, provided full-Sun Lyα profiles, not affected by such an absorption [Lemaire et al., 1998. Solar H I Lyman α full disk profile obtained with the SUMER/SOHO spectrometer. Astron. Astrophys. 334, 1095-1098; 2002. Variation of the full Sun Hydrogen Lyman α and β profiles with the activity cycle. Proc. SOHO 11 Symposium, ESA SP-508, 219-222; 2004. Variation of the full Sun Hydrogen Lyman profiles through solar cycle 23. COSPAR 2004 Meeting], making it—for the first time—possible to measure the spectral and total Lyα solar irradiances directly and simultaneously. A new relation between these two quantities is derived in an expression that is formally similar to the previous one, but with significantly different parameters. After having discussed the potential causes for such differences, it is suggested that the new relation should replace the old one for any future modeling of the numerous Lyα absorptions and emissions observed in the Solar System. 相似文献
958.
The effects of 60-day starvation on survival rate. condition index (CI) , changes ofnutrient composition of different tissues, respiration and excretion of scallop ChlartnCs farreri were studiedin laboratory from Oct. 17 to Dec. 15 ,1997. Two groups (control and starvation with 200 individualseach) were cultured in two 2 m3 tanks, with 31 to 32 salinity water at 1 7 “C . Starvation effects were mea-sured alter 1 0, 20, 40 and 60 days. There was no mass mortality of scallops cf the two tanks and survivalrates of the control and starvation groups were 93 .5 % and 92.0 %, respectively. Starvation had strongeffect on the meat condition of the scallops, especially after 10 days; when relative lipid percentagedropped sharply while relative protein percentage increased. The impact of starvation on the oxygen consumption mtc (OCR) and the ammonia-N cxcretion mtc (AER) was obvious. 相似文献
959.
M. A. Romanova 《Mathematical Geology》1991,23(7):959-979
A hypothesis for effects of stable tectonic elements on chemical composition of Mesozoic granitoids in northeastern Asia is tested. Chemical compositional change of granitoid rocks is examined in nine-dimensional space of rock-forming oxides. Stable geologic structures of the region are outlined by trends of Euclidean distances between rock recognized as a standard in a space of major rock-forming oxides and composition of individual samples. A data-smoothing polynomial of the fourth order corresponds closely to the geology of the region. Chemically stable masses of quartz diorite are thought to be delivered directly from magmatic sources along deep faults. A great variety of acidic granites, which occupy for each analysis separate cells in the nine-dimensional classification, are presumed to be palingenetic in origin. 相似文献
960.
Vegetation characteristics have not been sufficiently utilized in catchment runoff models. An analysis of storm hydrograph data from nested subareas of the Highland Water catchment, New Forest, U.K., indicates that depth of runoff and peak discharge from areas under heathland cover is substantially greater than from areas under woodland cover at several spatial scales. The significance of heath vegetation composition in the identification of runoff contributing areas is illustrated by an analysis of vegetation composition, water table depth, baseflow discharge and storm runoff from areas predominantly covered by heathland. Methods are proposed to employ the hydrological characteristics of heathland to refine and develop the Flood Studies Approach to discharge estimation in ungauged heathland catchments. Such an approach is greatly facilitated by the use of remotely-sensed data. 相似文献