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181.
李广 《科技情报开发与经济》2010,20(23):155-157
从阳高县马铃薯生产的现状入手,重点分析了马铃薯产业化发展的优势和存在的问题,并提出了今后产业化发展的具体措施和方向。 相似文献
182.
针对奉节县煤炭资源开发利用现状、分布和赋存特点等,分析了奉节县微小煤矿资源整合中存在的问题,提出了加强微小煤矿资源整合与发展的对策。 相似文献
183.
184.
我国新疆维吾尔自治区边境地区依托原始优美的生态环境,与丰富的民俗文化旅游资源,在发展边境旅游,取得了一些进展,也有一定的负面影响.文章主张实施旅游边贸互动发展,并注重旅游发展中生态环境和民俗风情的可持续利用,促进边境旅游的可持续发展. 相似文献
185.
利用显微凝集试验调查重庆市彭水县2001--2002年495名健康人群血清钩端螺旋体抗体水平.结果显示:健康人群阳性抗体率平均达到61.27%,与性别、年龄、职业有相关性;检测人群中含12群钩体血清抗体,滴度一般在1:20~1;320之间处于较低水平;阳性血清中2001年以56604拜伦型居多占阳性血清的59.8%,而在2002年以56007澳洲型居多占阳性血清的69.9%.以上结果提示彭水县人群存在钩体的隐形感染,但免疫水平低下,且可能有菌群更迭现象存在. 相似文献
186.
《科学通报(英文版)》2005,50(Z1):52-52
The Qinshui Basin in China is a major area for exploration and development of high rank coalbed methane. Due to the high rank coal and complicated pore system, no substantial breakthrough in the exploration and development of coalbed methane has been made until now. Many systematic tests show that a pore system of coal reservoir has some features as follows: the porosity is relatively low; the pore system is dominated by micropores and transition pores; mesopores take the second place, and macropores are nearly absent, which is exceedingly adverse for production of coal-bed methane. However, testing data also revealed the differential development for the pore of high rank coal reservoirs in the Qinshui Basin, which necessarily led to the different physical properties of desorption, diffusion and permeability. This paper classifies the testing data using cluster analysis method and selects the typical samples to establish four pore system models, analyzes the differences of reservoir physical property, and provides a guidance for the exploration and development of coalbed methane in the Qinshui Basin. 相似文献
187.
The evidence of fission-track data for the study of tectonic thermal history in Qinshui Basin 总被引:2,自引:0,他引:2
《科学通报(英文版)》2005,50(Z1):104-104
The thermal history of the Qinshui Basin has been studied by using the fission-track analysis of apatite and zircon, integrated analysis of tectonic evolution, magmatic activity and other palaeogeothermal analysis data. Results indicate that the palaeogeothermal gradient between the late-Paleozoic era and the medium-Mesozoic era is relatively low and the palaeogeothermal gradient in the late-Mesozoic is up to 5.56癈/100 m in the middle, and the values are relatively higher in the north and south margins of the basin, reaching over 8.00℃/100 m, which indicates that there was an anomalous tectonic thermal event in the thermal history of Qinshui Basin. This event happened in 110-140 Ma, and the main peak value was between 120 and 140 Ma. This anomalous tectonic thermal event is controlled by the strengthening thermal mobility of the lithosphere and magmatic intrusion. The maturity of the Permo-Carboniferous coal series mainly was controlled by this anomalous thermal field. The apatite fission track date of samples across the basin shows that a rapid tectonic uplifting with cooling existed 26.2-11.5 Ma ago and the upliftings in the north and south of the basin happened earlier than that in the middle. The Permo-Carboniferous strata had been completely annealed in the early 50 Ma, palaeotemperature over 125℃. Since then, especially from Oligocene-Miocene epoch, the strata which experienced large-scale tectonic upliftings with rapid cooling have been kept out of the annealing belt (70-125℃) in a relative low temperature environment. The late Mesozoic tectonic thermal event control hydrocarbon production peak (late Jurassic to early Cretaceous period) of Permo-Carboniferous strata in Qinshui Basin. When the strata experienced upliftings with rapid cooling since Oligocene-Miocene epoch, the hydrocarbon generation of coal series had stopped. 相似文献
188.
永顺县旅游资源深度开发初探 总被引:1,自引:0,他引:1
从永顺县旅游资源的整体特征分析入手,针对永顺县旅游资源的开发现状及存在的问题,提出了实施“大旅游”战略、旅游精品战略、旅游市场战略及塑造猛洞河风景名胜区旅游发展新格局、整合优化旅游产品、开发特色旅游商品、深化土家文化主题的对策。 相似文献
189.
通过对冕宁县发展优质双低油菜的思考,提出该县发展优质双低油菜应结合产业结构调整,保持高起点发展,充分发挥“优质双低无公害”品牌优势,建立“企业 农技部门 农户”的产业化模式和适度发展油菜籽深加工的建议。 相似文献
190.
The detailed14c dating, palynological, carbon isotope and magnetic susceptibility analyses of a paleo-swamp record obtained near Beijing
show that the succession of climate events in Beljing area is broadly consistent with the climatic behavior in the North Atlantic
region during the period from 13 000 to 10 000 a B. P., but with evident local characteristics. A relatively warm and wet
episode (11 400-10 950 a B.P.) was intercalated between two dry-cold episodes (11 600-11 400 and 10 950-10 450 a B. P.). 相似文献