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排序方式: 共有598条查询结果,搜索用时 46 毫秒
591.
正In China,the strategic resource potash is suffering from severe shortages,and the ancient marine solid potash locating is still a problem of long impregnability.Till now,only the Mengyejing Potash Deposit was found 相似文献
592.
Due to its unique geographic environment, Taiwan is prone to natural disasters such as earthquakes and typhoons that can cause heavy casualties and huge property losses. The effects of global warming have also increased extreme climate events and the frequency and severity of natural disasters. Therefore, disaster prevention/mitigation and response is not only an important government policy issue, but also an important daily life issue. To increase the awareness of natural disasters and the importance of community safety, the Taiwan government actively promotes a community disaster prevention system. However, to avoid over-reliance on the government taskforce, the spontaneous participation and cooperation within communities can complete specific disaster preparedness and reinforce local resources for disaster prevention and response. Although the concept of disaster-resilient community (DRC) has been shaped for a long period of time, community residents cannot keep pace with the government, which may decrease the effectiveness of DRC development. Therefore, theoretical and practical studies of urban DRC become imperative. This qualitative case study used the participant observation method to collect relevant empirical data by performing action research with self-reflection. Particularly, this article is supplemented by service work experience of the researchers in DRC promotion. A qualitative analysis of case communities during training in disaster preparedness revealed the critical success factors (CSFs) affecting the level of community-based disaster prevention and protection works. Based on the literature and empirical data, the CSFs are discussed through three spindle constructs: coping strategy, operations management, and organizational behavior. Finally, the conclusions and suggestions are given for promoting sustainable DRC. 相似文献
593.
为了对表碛覆盖型冰川边界进行识别并掌握其变化,以伦道夫(RGI6.0)冰川编目为基础,基于Sentinel-1数据运用时序InSAR技术对昆仑山东段表碛覆盖型冰川进行了形变监测。根据2014年10月至2020年9月表碛覆盖下冰川的时序形变情况,将InSAR形变与光学影像相结合验证冰川边界。结果表明:对昆仑山东段研究区域内280条冰川边界的研究中,探测到3处表碛覆盖型冰川,对边界进行调整后冰川面积分别增加0.19、0.1、0.18 km~2。根据时序形变,发现冰川表碛形变呈现明显的季节周期性,形变与温度、坡向显著相关。另外,表碛覆盖型冰川的变形幅度在(-5,5)cm范围内,暖季变形幅度最大,且地形对突变幅度造成影响。这表明时序InSAR技术可对表碛覆盖型冰川进行形变监测与识别研究。 相似文献
594.
Chou CL 《Marine pollution bulletin》2007,54(6):720-725
The study was undertaken to investigate the uptake of mercury in salmon throughout the entire farming period at the net cage. Mercury concentrations in muscle, liver, kidney, and gill and responses to the various dietary mercury concentrations were determined. The accumulation of mercury is in the order of kidney>gill=liver>muscle. The highest mercury peak concentrations were observed for both kidney and gill at the parr-smolt period, while liver and muscle mercury peaked one month later after caging at the grow-out site. High dietary sodium and calcium fed to the salmon contributed to the elevation of mercury in kidney and gill during the smolting process. The mercury burden over the grow-out period increased sharply with a linear relationship of mercury uptake. The tissue mercury burden per gram of growth was calculated using the slope of mercury burden and the slope of growth over the period of each stage. The results showed dietary mercury loadings on marketable salmon were within tolerance limits of FDA and US EPA. Rapid growth of salmon and low dietary mercury progressively reduces the uptake of mercury in salmon. The time series of mercury monitoring showed that mercury concentrations in salmon were greater at the parr stage in freshwater than at the grow-out stage in salt water. 相似文献
595.
LI Qiming WU Guanghui PANG Xiongqi PAN Wenqin LUO Chunshu Wang Chenglin LI Xinsheng ZHOU Bo 《《地质学报》英文版》2010,84(5):1180-1194
<正>Based on comprehensive analysis of reservoir-forming conditions,the diversity of reservoir and the difference of multistage hydrocarbon charge are the key factors for the carbonate hydrocarbon accumulation of the Ordovician in the Tarim Basin.Undergone four major deposition-tectonic cycles, the Ordovician carbonate formed a stable structural framework with huge uplifts,in which are developed reservoirs of the reef-bank type and unconformity type,and resulted in multistage hydrocarbon charge and accumulation during the Caledonian,Late Hercynian and Late Himalayan. With low matrix porosity and permeability of the Ordovician carbonate,the secondary solution pores and caverns serve as the main reservoir space.The polyphase tectonic movements formed unconformity reservoirs widely distributed around the paleo-uplifts;and the reef-bank reservoir is controlled by two kinds of sedimentary facies belts,namely the steep slope and gentle slope.The unconventional carbonate pool is characterized by extensive distribution,no obvious edge water or bottom water,complicated oil/gas/water relations and severe heterogeneity controlled by reservoirs. The low porosity and low permeability reservoir together with multi-period hydrocarbon accumulation resulted in the difference and complex of the distribution and production of oil/gas/water.The distribution of hydrocarbon is controlled by the temporal-spatial relation between revolution of source rocks and paleo-uplifts.The heterogenetic carbonate reservoir and late-stage gas charge are the main factors making the oil/ gas phase complicated.The slope areas of the paleo-uplifts formed in the Paleozoic are the main carbonate exploration directions based on comprehensive evaluation.The Ordovician of the northern slope of the Tazhong uplift,Lunnan and its periphery areas are practical exploration fields.The Yengimahalla-Hanikatam and Markit slopes are the important replacement targets for carbonate exploration.Gucheng,Tadong,the deep layers of Cambrian dolomite in the Lunnan and Tazhong-Bachu areas are favorable directions for research and risk exploration. 相似文献
596.
库车前陆盆地古近系—新近系铜矿化特征及铜的来源、富集分布初探 总被引:1,自引:0,他引:1
库车盆地铜成矿作用发生在新近纪,主要有砂岩型、泥岩型、灰岩型铜矿化。矿化主要分布于盆地南部的秋里塔格构造带和北部的克拉苏构造带,基本位于背斜核部偏两翼部位,沿近东西向的断裂带呈带状分布,发育在盐丘附近。主要的地表铜矿物为氯铜矿,是干旱气候条件下含盐盆地的产物。盆地古近系石盐、石膏样品电镜分析、石膏铜含量化学分析及新近系碎屑岩中铜含量变化分析结果表明:盐岩、膏岩,褐红色碎屑岩(粉砂岩、泥质粉砂岩、泥岩)为铜的矿源层,灰绿色粉砂岩、泥岩、灰白色(含砾)中粗砂岩为铜的含矿层。铜离子的运移载体主要为源自大气降水溶解石盐、石膏所形成的卤水,卤水淋滤褐红色碎屑岩中的铜并下渗到地下,在以构造挤压为主及盐构造卸负作用产生流体上涌的驱动力下沿断裂向地表运移,随着卤水温度压力降低,干旱气候条件下,在地表碎屑岩节理面、部分层理面上发育石盐、石膏及氯铜矿,形成地表砂岩型、泥岩型、灰岩型铜矿化。当含铜卤水经过被方解石交代的硬石膏带(氧化-还原化学障)时,遇到因TSR反应形成富含还原硫的卤水,铜会发生富集,可能形成地下铜矿体。 相似文献
597.
Vivek Walia Shih Jung Lin Ching Chou Fu Tsanyao Frank Yang Wei-Li Hong Kuo-Liang Wen Cheng-Hong Chen 《Applied Geochemistry》2010
Many studies have shown the soil gas method to be one of the most reliable investigation tools in the research of earthquake precursory signals and fault delineation. The present research is aimed finding the relationship between soil gas distribution and tectonic systems in the vicinity of the Hsinhua Fault zone in the Tainan area of Southern Taiwan. More than 110 samples were collected along 13 traverses to find the spatial distribution of Rn, He, CO2 and N2. The spatial congruence of all the gases shows that N2 is the most probable carrier gas of He, whereas CO2 seems to be a good carrier gas of Rn in this area. From the spatial distribution of Rn, He, CO2 and N2 the trace of Hsinhua Fault and neotectonic features can be identified. The spatial distribution of studied gases shows a clear anomalous trend ENE–SWS along the Hsinhua Fault. 相似文献
598.
Vegetation recovery and landscape change assessment at Chiufenershan landslide area caused by Chichi earthquake in central Taiwan 总被引:1,自引:1,他引:0
This study discusses vegetation recovery and land cover change with reference to the Chiufenershan landslide, a major disaster
caused by the Chichi earthquake, 21 September 1999. Image classification technology, landscape indicators from multi-temporal
remotely sensed data and a field survey provide the data. Image differencing methods and threshold values coupled with pre-
and post-quake satellite images were used. Multi-temporal images in combination with various vegetation indices were drawn
on to classify land cover patterns and discuss differences and suitability of indices. Landscape indicators and field investigations
fed into an investigation of vegetation recovery and landscape change. The study results show that the best image classification
system is original wavebands coupled with a cropping management factor index (CMFI). The land cover analysis shows that areas
of forest and grass are increasing and areas of landslide are decreasing. From the field investigation, because the left and
right sides of the landslide area were not disturbed by the earthquake, their calculated similarity index is the highest (30.08%).
Miscanthus floridulus is the most dominant pioneer plant at the landslide collapse area with an importance value index (IVI) of 63.6%. 相似文献