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71.
Gusev  E. M.  Nasonova  O. N.  Busarova  O. E. 《Water Resources》2002,29(1):99-110
A technique is proposed for parameterization of the process of heat and moisture exchange between the underlying surface and the atmosphere at a regional scale under moderate continental climate, which implies a long cold period with stable snow cover and seasonally frozen soil. The technique allows the heterogeneity of the area under consideration to be explicitly accounted for in the model through properly selecting the model grid. The details at a scale below the grid size, such as the presence of field or forest ecosystems in any grid cell, also can be incorporated in the model. The proposed technique has been tested against unique observational data along with published scientific generalization for the Polomet River basin (Valdai Hills), which is 1215 km2 in area.  相似文献   
72.
范福南  邢富  范秀娥 《岩矿测试》2002,21(3):219-222
利用BaSO4在高热H2 SO4中能定量地形成液态Ba(HSO4) 2 ,而当含Ba(HSO4) 2 的浓H2 SO4溶液被稀释时 ,又能重新定量析出BaSO4这一性质 ,拟定出高热H2 SO4溶解重量法测定矿石中的钡。方法用于矿石、重晶石单矿物中BaO和BaSO4的测定 ,结果与碱熔BaSO4重量法、BaCrO4容量法、外检结果相一致 ,精密度试验结果 ,相对标准偏差RSD(n =1 0 ) <5 %。  相似文献   
73.
The Effelsberg‐Bonn H I survey (EBHIS) comprises an all‐sky survey north of Dec = –5° of the Milky Way and the local volume out to a red‐shift of z ≃ 0.07. Using state of the art Field Programmable Gate Array (FPGA) spectrometers it is feasible to cover the 100 MHz bandwidth with 16.384 spectral channels. High speed storage of H I spectra allows us to minimize the degradation by Radio Frequency Interference (RFI) signals. Regular EBHIS survey observations started during the winter season 2008/2009 after extensive system evaluation and verification tests. Until today, we surveyed about 8000 square degrees, focusing during the first all‐sky coverage of the Sloan‐Digital Sky Survey (SDSS) area and the northern extension of the Magellanic stream. The first whole sky coverage will be finished in 2011. Already this first coverage will reach the same sensitivity level as the Parkes Milky Way (GASS) and extragalactic surveys (HIPASS). EBHIS data will be calibrated, stray‐radiation corrected and freely accessible for the scientific community via a webinterface. In this paper we demonstrate the scientific data quality and explore the expected harvest of this new all‐sky survey (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
74.
Izvestiya, Physics of the Solid Earth - The largest instrumentally recorded regional back-arc earthquake with MW = 7.8, MC = 8.2 occurred on July 17, 2017 on the Bering transform fault (the...  相似文献   
75.
76.
A brief survey of the results obtained by the authors in the development and investigation of the algorithms of numerical simulation of the motion of solar system small bodies is given. New approaches to the construction of the algorithms of high-accuracy numerical simulation of the dynamics of small bodies and the methods of the determination of the domain of their possible motions are presented.  相似文献   
77.
We have used surface photometry data for 100 barred galaxies to determine the UBVRIJHK surface brightnesses and color indices for the bars. Two peaks are observed in the distribution of the average bar B brightnesses: at 21.0m/arcsec2 and 22.2m/arcsec2, characteristic of late-and early-type galaxies, respectively. The average surface-brightness difference between the bar and the galaxy (within the 25.0m/arcsec2 isophote) increases from 1.1m/arcsec2 for SB0 galaxies to 2.3m/arcsec2 for SBc-IBm galaxies. In (U-B)0-(B-V)0, (B-V 0-(V-R 0, and (B-V)0-(V-I)0 two-color diagrams, for all morphological types, the bars are shifted leftward from normal color sequence for galaxies. This deviation is more pronounced for the outer than for the inner regions of the bars. Using evolutionary models, we show that this deviation is due to the scarcity of intermediate-age [(1–9)×109 yrs] stars in bars. Possible origins for this anomalous composition of the stellar population are discussed.  相似文献   
78.
The molluscan shells from three drill and two piston cores obtained in the southern Russian sector of the Chukchi Sea are dated by the AMS 14C measurement method back to 0.8–3.5 and 9.2–10.5 ka. The period of 9–10 ka was marked by increased sedimentation rates related to the transgression onset. The fossils in the lower Holocene section exhibit the successive upward replacement of brackish-water organisms by their marine counterparts. After the opening of the Bering Strait in the middle Holocene, the sedimentation was under influence of the increased bioproductivity of the waters. The climatic optimum in the Chukotka region corresponds to the early Holocene, while the late Holocene was characterized by the wider development of the ice cover on the shelf.  相似文献   
79.
吕梁山区出现局地大暴雨为小概率事件,在县局的订正预报中有很大的难度。2010年8月11日位于吕梁市东北端的岚县出现了106.2mm的大暴雨,而吕梁的其它县、市只出现中雨以下量级降水。本文分析了造成本次强降雨的高低空环流形势、主要影响系统、水汽条件、云图与雷达回波资料以及本县特殊的地形特征等结果表明:本次局地大暴雨天气是由高空短波槽、中层切变线、副热带高压边缘西南暖湿气流共同作用产生的;对流层低层强盛的偏南气流为大暴雨提供了源源不断的水汽;地面弱低压加强了辐合上升运动,特殊地形的抬升与阻挡作用,使强回波雨团长时间在迎风坡下的平坦地段停留,从而造成局地性的强降水。  相似文献   
80.
Many climatic parameters (ground and ocean surface temperatures, pressure, atmospheric precipitation, etc.) have temporal variations with characteristic periods from several to several tens of years or more. The unknown cause of these oscillations, together with the similarity of some of them to known solar cycles, has stimulated attempts to relate these two phenomena. The basic arguments against the existence of such a relationship are that variations in climatic parameters do not always occur synchronously with the corresponding 11- and 22-year solar cycles: the phase shift between climatic and solar variations is inconstant and changes with time from 0° to 180°. In addition, the energy of terrestrial manifestations of solar activity seems insufficient to stimulate the considered weather-climatic processes, at least within the limits of the linear approach. In the present work, it is shown that in some cases, these contradictions can be removed for variations with a period more than 11 years under the assumption that climatic variations are forced oscillations driven by an external force (for example, a force related to solar activity), that implies the existence of intrinsic (natural) climatic oscillations. The result serves as an additional argument in favor of the reality of a sun-climate connection and probably points to its probable nonlinear mechanism.  相似文献   
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