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81.
玉石洼铁矿伴生钴的赋存状态及综合利用初探 总被引:1,自引:0,他引:1
玉石洼铁矿伴生的钴含量较高,主要以类质同象形式存在于伴生的黄铁矿中,与硫存在着正相关关系,应用合适的提钴工艺,黄铁矿中大部分的钴可以提取出来。此区钴资源量丰富,如能综合利用,潜在经济效益可观。 相似文献
82.
Holocene Saline Sedimentary Record in Tibetan Dong Co (Lake) and Its Significance on Palaeoclimate 总被引:2,自引:0,他引:2
HOLOCENE SALINE SEDIMENTARY RECORD IN TIBETAN DONG CO(LAKE) AND ITS SIGNIFICANCE ON PALAEOCLIMATE 相似文献
83.
藏南沉错湖泊三角洲的沉积相及沉积环境 总被引:3,自引:0,他引:3
在西藏自治区沉错湖泊三角洲平原和湖内钻孔取芯 ,利用14 C和ESR测年方法建立了钻孔剖面的年代标尺。在岩芯描述、沉积物粒度分析和CaCO3含量分析基础上 ,对沉错湖泊三角洲的沉积环境和沉积相进行了解释分析。 36 7m长的岩芯大致记录了 5 5万年以来的沉积历史。全孔平均沉积速率约为 0 6 6 7mm/a。 16 92 0aBP以来三角洲的沉积速率较大 ,平均为 1 2 7mm/a。由于沉积物物质来源的多源性导致CaCO3在剖面上的无规律性变化。但是 ,沉积物粒度和沉积序列变化指示全套沉积由底部的冲积扇相向上过渡为水下扇亚相和三角洲沉积相。在大约 175 0 0aBP~ 14 0 0 0aBP时期 ,沉错存在高湖面阶段。沉积序列中记录了末次冰期最盛期 (LastGlacialMaximum )和新仙女木事件 (YoungerDryas)。沉积特征和沉积环境的变化主要受湖面涨缩变化所控制。而湖面升降变化的驱动因素主要为气候 ,尤其夏季风的强弱和冷事件 相似文献
84.
Quantitative comparison of river inflows to a rapidly expanding lake in central Tibetan Plateau
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The recent rapid expansion of inland lakes on the Tibetan Plateau (TP) are a good indicator of the consequences of climate change. Quantifying the hydrological cycle of the lake basin is fundamentally important to understand the causes of lake growth. However, the hydrological processes of the TP interior are very complex and difficult to investigate because of the lack of observations. This is especially true for estimating the lake changes when run‐off inflows are affected by small lakes located in the flow routes within drainage areas. We used an integrated hydrological model, in combination with glacier melt and lake retention models, to analyse the run‐off inflows to Lake Siling Co, the largest endorheic lake in Tibet. It includes four subdrainage basins: Zhajiazangbu, Zhagenzangbu, Alizangbu, and Boquzangbu. Lake Siling Co was characterized by considerable increases during warm season from 1981 to 2012, due to the increased run‐off from Zhajiazangbu accounting for about 51–62% of the total run‐off inflows. Moreover, the dramatic increases exhibited during cold seasons were related to the increased retention water released from the small lakes within Zhagenzangbu and Alizangbu. Of the studied subdrainage basins, Boquzangbu contributed the least during both warm and cold seasons. On average, the annual amount of evaporation from lakes within the drainage area was about 2 times greater than that of glacier melt run‐off. Our results suggest that the retention effects of lakes on river inflows should receive more attention, because understanding these effects is potentially crucial to improved understanding of lake variations in the TP. 相似文献
85.
Research on surface water temperature (SWT) variations in large lakes over the Qinghai–Tibet Plateau (QTP) has been limited by lack of in situ measurements. By taking advantage of the increased availability of remotely sensed observations, this study investigated SWT variation of Siling Co in central QTP by processing complete MODIS Land surface temperature (LST) images over the lake covering from 2001 to 2013. The temporal (diurnal, intra-annul and inter-annul) variations of Siling Co SWT as well as the spatial patterns were analyzed. The results show that on average from late December to mid-April the lake is in a mixing state of water and ice and drastic diurnal temperature differences occur, especially along the shallow shoreline areas. The extent of spatial variations in monthly SWT ranges from 1.25 °C to 3.5 °C, and particularly large at nighttime and in winter months. The spatial patterns of annual average SWT were likely impacted by the cooling effect of river inflow from the west and east side of the lake. The annual cycle of spatial pattern of SWT is characterized by seasonal reversions between the shallow littoral regions and deep parts due to different heat capacity. Compared to the deep regions, the littoral shallow shoreline areas warms up quickly in spring and summer, and cool down drastically in autumn and winter, showing large diurnal and seasonal variation amplitudes of SWT. Two cold belt zones in the western and eastern side of the lake and warm patches along the southwestern and northeastern shorelines are shaped by the combined effects of the lakebed topography and river runoff. Overall, the lake-averaged SWT increased at a rate of 0.26 °C/decade during 2001–2013. Faster increase of temperature was found at nighttime (0.34 °C/decade) and in winter and spring, consistent with the asymmetric warming pattern over land areas reported in prior studies. The rate of temperature increase over Siling Co is remarkably lower than that over Bangoin station, which is probably attributable to the large heat capacity of water and partly reflects the sensitive of alpine saltwater lake to climate change. 相似文献
86.
87.
Yimin Wang Xiaohong Wang Wenjun Qu Yushu Gao Tiexin Gu Xingtao Fan S.I. Andreev Xuefa Shi 《Geostandards and Geoanalytical Research》2011,35(3):341-352
Two Co‐rich seamount crust reference materials, MCPt‐1 and MCPt‐2, were prepared using ultra‐fine particle size milling technique and characterised for the platinum‐group elements (PGEs). The raw material for these two reference materials was collected separately from the Magellan seamounts of the western Pacific Ocean and the seamounts of the central Pacific Ocean by Russian and Chinese scientists. First, they were ground by ball mill to a ?200 mesh powder, then further processed by ultra‐fine jet mill and well‐mixed. The particle size distributions of the samples were tested by a laser particle analyser; the average particle size was 1.8 and 1.5 μm (equal to about 2000 mesh) respectively. The homogeneity of six major and minor elements in these two materials was tested at the milligram level of sampling mass by high‐precision wavelength dispersive X‐ray fluorescence (XRF) spectrometry and at the microgram level of sampling mass by electron probe microanalyser. The homogeneity of more than forty trace elements, including Pt, was tested at the microgram level of sampling mass by LA‐ICP‐MS. Except for Rh, all PGEs were determined by isotope dilution‐ICP‐MS. Platinum in MCPt‐1 and MCPt‐2 was characterised as certified values, whereas the other five PGEs in MCPt‐1 and MCPt‐2 were reported as reference values. In addition, the information values of sixty‐two major, minor and trace elements were obtained by XRF, ICP‐AES and ICP‐MS. The minimum sampling mass for the determination of PGEs was 1 g, while the minimum sampling mass for the determination of the other elements was 2–5 mg. 相似文献
88.
Abstract Digitizing still remains a major bottle-neck in the creation of geographical data bases. This paper examines procedures and equipment used in the Dane County Land Records Project as a tutorial for others interested in digitizing maps. Topological structure, determined from ‘spaghetti and meatballs’, detects the important errors and provides a basis for efficiency (in time and cost). For manual digitizing, a simple system of capture running on cheap hardware may be as effective as an expensive workstation. Scanning technology, which used to be expensive, has now become practical, as is shown by an experimental scanner used in this project. 相似文献
89.
90.
Yan‐Peng Mao Yu Chen Jing‐Yi Cheng Hai‐Song Zhu Xiang‐Li Long Wei‐Kang Yuan 《洁净——土壤、空气、水》2012,40(2):117-122
A novel method has been put forward to retrofit the wet ammonia desulfurization process to realize the combined removal of sulfur dioxide and nitric oxide by introducing soluble cobalt(II) salt into aqueous ammonia solution. The active constituent of scrubbing NO from the flue gases is the produced by ammonia coordinating with Co2+. The regeneration of can be realized under the catalysis of activated carbon so as to sustain a high NO removal efficiency for a long time. In this paper, the adsorption–reduction behavior of on activated carbon has been researched using scanning electron microscopy, X‐ray diffraction, and X‐ray photoelectron spectroscopy. A conclusion can be drawn from the results that cobalt ions in the aqueous solution are adsorbed by activated carbon and most of them are reduced to Co2+ ions, and some of the Co2+ ions are further reduced into metallic cobalt. The results also demonstrate that the functional groups on the surface of carbon take part in this redox reaction. The C? H groups on the carbon surface are oxidized into C? OH, and then some of the hydroxyl groups are further oxidized into carbonyl or carboxyl groups. 相似文献