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61.
Chemical and isotopic data were measured for 51 leached brine springs in the Changdu-Lanping-Simao Basin (CD-LP-SM), China. The predominance of Cl and Na, saturation indices of carbonate minerals, and Na/Cl and Ca/SO4 ratios of ~1 suggest that halite, sulphate, and carbonate are the solute sources. Integration of geochemical, δ18O, and δD values suggests that springs are mainly derived from meteoric water, ice-snow melt, and water-rock interactions. B concentrations range from 0.18 to 11.9 mg/L, with δ11B values of ?4.37‰ to +32.39‰, indicating a terrestrial source. The δ11B-B relationships suggest B sources of crustal origin (marine carbonates with minor crust-derived volcanics); we did not identify a marine or deep mantle origin. The δ11B values of saline springs (+4.61‰ to +32.39‰) exceed those of hot (?4.37‰ to +4.53‰) and cold (?3.47‰ to +14.84‰) springs; this has contributed to strong water-rock interactions and strong saturation of dissolved carbonates. Conversely, the global geothermal δ11B-Cl/B relationship suggests mixing of marine and non-marine sources. The δ11B-Cl/B relationships of the CD-LP-SM are similar to those of the Tibet geothermal belt and the Nangqen Basin, indicating the same B origin. These differ from thermal waters controlled by magmatic fluids and seawater, suggesting that B in CD-LP-SM springs has a crustal origin.  相似文献   
62.
周侃  申玉铭  任旺兵 《地理学报》2011,66(10):1355-1367
通过对中国31 个省(市、自治区)近4000 个服务业企业的问卷调查,从服务业企业认知与体验的视角出发,对“十一五”时期中国服务业政策效应进行综合测度和影响因素分析,进而探讨服务业政策与服务业企业的作用机制,并提出中国服务业政策调整和优化的建议。结果表明: “十一五”时期服务业企业对服务业政策的认知水平不高,认知度受到营业额、劳动力素质、行业类型、行业地位和政策环境等因素的显著影响。企业对服务业政策的体验水平接近比较满意, 影响政策体验水平的因素主要有政策认知度、员工人数、效益、所有制类型、行业地位和政策环境等。针对中国服务业政策与服务业企业的作用机制,应从深化服务业体制改革、完善社会保障体系、平衡内外资鼓励政策、拓宽政策支持覆盖面、构建服务业企业对服务业政策实施情况的反馈机制等方面着手,推动转型期中国服务业向高比重、高效率方向发展。  相似文献   
63.
对山西娘子关绵河不同阶地上沉积的泉钙华进行了高精度的230Th定年和碳氧稳定同位素组成测定。结果发现,绵河II级阶地沉积的娘子关泉钙华的最老年龄在407~466ka,远老于早前通过钙华中的石英砂热发光法(TL)获得的年龄,即绵河II级阶地上的娘子关泉钙华是在中更新世MIS12/11阶段形成的,而非原来认为的是晚更新世的产物。由此推测,绵河III级阶地娘子关泉钙华形成的年代更早,可能是中更新世的MIS14/13阶段。230Th测年获得的绵河I级阶地顶部的钙华形成于5ka前,即是在全新世中期以前形成的。结合钙华规模及其碳氧稳定同位素组成分析进一步发现,上述绵河三级阶地上的娘子关泉钙华均主要是湿热气候下的产物。然而,自II级阶地钙华形成至今,气候总体上在向干冷方向发展,泉域植被则呈现退化的趋势。  相似文献   
64.
65.
1. Introduction Ocean General Circulation Models (OGCMs) arekey tools in the assessment of the future ocean up-take of atmospheric greenhouse gases and heat. Fur-thermore, whereas nature experiences one realisationof the climate state, climate models can be used as alaboratory to produce a multitude of climate realisa-tions, and by that contribute to the understanding ofthe variability and stability properties of the system.It is, in this respect, crucial to evaluate the climatemodels ag…  相似文献   
66.
介绍了编制DINI11数字水准仪观测资料后,处理软件的设计思路和实现方法,该软件自动完成观测资料入库、计算、打印手簿、成果表和画时序图等任务。  相似文献   
67.
罗氏沼虾仔虾及蚤状Ⅺ期幼体对盐度突变的适应试验   总被引:1,自引:0,他引:1  
本文试验了罗氏沼虾仔虾及Z11期幼体对盐度突变的适应能力。试验结果表明,0.82cm的仔虾由盐度10.8‰放入淡水中及0.98cm的仔虾由淡水直接放放20‰以下盐度水中培育,对虾仔的成活影响不明显;Z11期幼体由盈度17‰直接放入7—17‰盐度水中和由盐度10.8‰放入4—10.8%盐度水中以及淡化后第二天由淡水直接放入17‰盐度水中培育,对幼体的成活率无明显影响,幼体能正常蜕皮变态。  相似文献   
68.
We discuss the formation of pulsars with massive companions in eccentric orbits. We demonstrate that the probability for a non-recycled radio pulsar to have a white dwarf as a companion is comparable to that of having an old neutron star as a companion. Special emphasis is given to PSR B1820−11 and PSR B2303+46. Based on population synthesis calculations we argue that PSR B1820−11 and PSR B2303+46 could very well be accompanied by white dwarfs with mass ≳1.1 M. For PSR B1820−11, however, we cannot exclude the possibility that its companion is a main-sequence star with a mass between ∼0.7 M and ∼5 M.  相似文献   
69.
This study summarizes the final results of magnetostratigraphic and micropalaeontological investigations of the Tithonian/Berriasian boundary (J/K) limestones at the locality of Brodno near ilina, Western Carpathians, West Slovakia. The aim is to prepare the background for correlation of a Late Tithonian and Early Berriasian biostratigraphic zonation with global magnetoevents (manifested in detailed magnetostratigraphic profiles) between the Tethyan realm and other regions, particularly the Boreal and Pacific realms. Suitable physical properties of the limestones studied, a favourable geological setting and rich microfossil assemblages (calpionellids) at Brodno (magnetozones M21r to M18r) allowed a systematic collection of new data on the original synoptic section, which now has the character of a high-resolution profile across the J/K boundary. Two reverse subzones detected within magnetozones M20n and M19n are named ‘Kysuca Subzone’ and ‘Brodno Subzone’, respectively. Both can be correlated with analogous subzones in the M-sequence of marine anomalies. Their existence can also be confirmed in the Bosso Valley section in Umbria, central Italy. A detailed study of the interval between magnetozones M20n and M17r in the Bosso Valley profile is presently in its final stage. Both magnetostratigraphic profiles, from the Brodno and Bosso Valley localities, were thoroughly investigated in the intervals close to the J/K boundary and are still unique among continent-based profiles in the detection and precise definition of both reverse subzones within M20n and M19n. Samples collected from the boundary strata of the reverse Kysuca Subzone at Brodno indicated a transition from N (R) to R (N) polarity of the Earth's palaeomagnetic field within a time interval of c. ±5 ka. Limestone samples (total number N=368) were subjected to progressive thermal demagnetization in 10–12 thermal fields and to subsequent multi-component analysis of remanence. The C-component, as the carrier of palaeomagnetic directions, was determined in the temperature interval of 300° to 540°, or possibly 580°C. Magnetomineralogical analyses of pilot samples and unblocking temperatures determined for all samples showed that magnetite is the carrier of remanent magnetization. The positions of the individual events of calpionellid stratigraphy relative to the global magnetic polarity timescale are precisely defined. The base of the Calpionella Standard Zone, which is considered a provisional J/K boundary indicator in ammonite-free sections in the Tethyan realm, lies within magnetozone M19n at the level of 35% of its local thickness. None of the boundaries in the calpionellid zonation coincides precisely with any of those in the palaeomagnetic zonation, but the first appearance ofCalpionella grandalpina , indicating the base of the Intermedia Subzone, lies in close proximity to the base of magnetozone M19r.  相似文献   
70.
From the synopical CTD sections in the WOCE PR11 repeated cruises, the South Pacific Subtropical Mode Water (SPSTMW) has been identified in the region of the Tasman Front Extension (TFE) around 29?S to the east of Australia. In the depth range of 150-250 m, the SPSTMW appears as a thermostad with vertical temperature gradient lower than 1.6℃(100 m)-1 and a tem- perature range of 16.5-19.5℃ and as a pycnostad with PV lower than 2×10-10 m-1 s-1 and a potential density range of 25.4-26.0 kg m-3. Like the subtropical mode waters in the North Atlantic and North Pacific, the formation of the SPSTMW is associated with the convective mixing during the austral wintertime as manifested from the time series of the Argo floats. And cold water entrains into the mixed layer with the deepening mixed layer from September to the middle of October. During the wintertime formation process, mesoscale eddies prevailing in the TFE region play an important role in the SPSTMW formation, and have a great effect on the SPSTMW distribution in the next year. The deeper (shallower) mixed layer in wintertime, consistent with the depressed (uplifted) permanent thermocline, is formed by the anticyclonic (cyclonic) eddies, and the substantial mode water thicker than 50 m is mainly found in the region of the anticyclonic eddies where the permanent thermocline is deeper than 450 m.  相似文献   
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