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41.
在试验的基础上,对油气化探固定波长同步荧光测试技术中光谱图的认识、波长差与方法灵敏度的关系以及同步荧光与其他荧光方法的内在关系等问题作了深入的研究和探讨,澄清了该技术在实际应用工作中较易产生混淆的几个问题,旨在推动该项技术在油气化探工作中的进一步应用和发展.  相似文献   
42.
Studies on rain-runoff process in the peripheral mountainous area of the Sichuan Basin, which is regarded as a key ecological shelter, will contribute to flood control and environmental protection for the Upper Yangtze River Basin. In two typical catchments--the Fujiang River Catchment and the Wujiang River Catchment, rainfall simulations have been conducted to study the rain-runoff processes of yellow soil and limestone soil in three types of land use--forestland, farmland and grassland. Results showed that (1) within the same rainfall process, overland flow occurs first on farmland, then on grassland, and finally on forestland; (2) soil surface coverage has a great impact on the occurrence and amount of overland flow. The runoff amount can increase 2-4 times after the coverage is removed; (3) the infiltration before the occurrence of overland flow will decrease because of higher gravel contents of soil, but it takes no effect on infiltration once overland flow becomes stable; (4) the runoff coefficient of the limestone soil forestland is greater than that of the yellow soil forest land, but less than that of the farmland; (5) three empirical infiltration models, including Horton' model, Kostiakov' model, and modified Kostiakov' model, were compared by using the observed results under rainfall simulation. The results showed that the Kostiakov' model performed better than both the Horton' model and modified Kostiakov model. According to the results of this research, the Kostiakov's model can be used to simulate rainfall infiltration when water erosion is modeled in the peripheral mountainous area of the Sichuan Basin.  相似文献   
43.
The authors investigated the effect of Bacillus mucilaginosus on weathering of phosphorite. Analysis of different proteins was of significance in exploring the molecular biological mechanism in the bacterial weathering process. The concrete methods are described as follows: Mineral powder was put into liquid culture medium and B. mucilaginosus was incubated in the medium. The control (group) had no mineral powder in the medium. The treatments and controls were cultured simultaneously under the same condition. In a few days, the supernatant was filtrated, the main cations (Ca^2+, Mg^2+, Na^+, Mn^2+, Al^3+, Fe^3+, K^+) were measured by ICP-OES, and the contents of water soluble phosphorus (Pws) and silicon (Siws) were determined by colorimetry. The residual solid was weighed on the filter paper, followed by digestion with concentrated HNO3. The concentrations of the main cations and Pws, Siws in the digest liquid were measured by using the method mentioned above. After the supernatant was centrifuged, the precipitation was used to analyze the protein differences between the treatment groups and the control groups by 2-dimentional gel electrophoresis (2-DE). The experimental results showed that apatite and quartz were partially weathered, but kaolinite was dissolved completely. The population of bacteria increased when mineral powder was added in the liquid medium. Software analysis and comparison of the 2-DE pictures of bacterial proteins revealed 1134 visible protein spots in the treatment group, and 729 visible protein spots in the control group. To compare the bacterial protein expression contents of the treatment group with those of the control group, there were 496 different protein spots, including 214 protein spots which indicated that the protein contents increased, 75 protein spots were indicative of a decrease, and 207 proteins were newly synthesized. It is proposed that the increased bacterial contents may be related to some protein expression and activation after the  相似文献   
44.
The study evaluated the performance and suitability of AnnAGNPS model in assessing runoff, sediment loading and nutrient loading under Malaysian conditions. The watershed of River Kuala Tasik in Malaysia, a combination of two sub-watersheds, was selected as the area of study. The data for the year 2004 was used to calibrate the model and the data for the year 2005 was used for validation purposes. Several input parameters were computed using methods suggested by other researchers and studies carried out in Malaysia. The study shows that runoff was predicted well with an overall R2 value of 0.90 and E value of 0.70. Sediment loading was able to produce a moderate result of R2 = 0.66 and E = 0.49, nitrogen loading predictions were slightly better with R2 = 0.68 and E = 0.53, and phosphorus loading performance was slightly poor with an R2 = 0.63 and E = 0.33. The erosion map developed was in agreement with the erosion risk map produced by the Department of Agriculture, Malaysia. Rubber estates and urban areas were found to be the main contributors to soil erosion. The simulation results showed that AnnAGNPS has the potential to be used as a valuable tool for planning and management of watersheds under Malaysian conditions.  相似文献   
45.
藏南冈底斯带西段麦拉花岗岩锆石SHRIMP定年及地质意义   总被引:1,自引:0,他引:1  
用SHRIMP测定了冈底斯岩带西段麦拉山口岩体同碰撞黑云母二长花岗岩锆石的U-Pb年龄,黑云母二长花岗岩锆石SHRIMP U-Pb年龄为47.1±1.1Ma。这就为前人提出的雅鲁藏布江地区洋盆闭合、板块开始碰撞的时间为50Ma左右提供了同位素年代学的证据。  相似文献   
46.
基于多分辨率小波变换,针对高分辨率全色图像和多光谱图像的融合,提出了一种基于方向可调滤波器的区域能量测量的小波变换融合算法.将此方法与HIS和传统小波的融合方法比较,结果表明,该方法在保留多光谱图像光谱信息的同时,能够更好地保留高分辨率图像的空间信息,融合效果有较大改善.  相似文献   
47.
"5.12"四川汶川8级大地震发生后,中国国土资源航空物探遥感中心立即采用"赛斯纳"高空遥感飞机,携带高清晰彩色数码相机及先进的POS系统,迅速获取了重灾区的航摄图像数据。本文以震中附近的映秀镇地区为例,简要介绍了以该高质量航摄数据为基础,采用数字滑坡技术,快速进行震后重灾区灾情及次生地质灾害遥感调查的成果。  相似文献   
48.
国土资源数据分析及其整合与集成   总被引:4,自引:1,他引:3  
本文详细分析了国土资源数据特点、综合数据来源、产生方式和使用方法等方面,对数据进行了分类,比较了不同的数据格式。在此基础上,阐述了国土资源数据的集成框架,讨论了数据整合和集成的方法和流程,提出了数据整合与集成的三种框架问题。  相似文献   
49.
董斌  李欣  郭高峰  王胤 《世界地质》2008,27(1):73-75
依据工程实例中桩顶位移数据,利用位移与内力之间的关系,采用"m"法,进行反分析研究.结果表明,支护桩桩顶理论位移为147.9 mm,与实际位移64 m差距较大,所以高回填土c,φ值所采用的经验值不精确.本文给出了长春地区回填土c,φ值的折减系数(分别为1.4和1.28).  相似文献   
50.
基于栅格空间数据的粤北山区土地可持续利用评价   总被引:1,自引:0,他引:1  
土地可持续利用是区域发展的立足之本,是可持续发展战略的核心内容之一,进行科学的土地可持续利用评价具有十分重要的意义。选择粤北山区的韶关市作为研究区域,利用遥感和G IS技术,构建一套适合研究区域的土地可持续利用评价指标体系,并提出一个土地可持续利用定量评价模型。然后对评价指标数据进行标准化和空间化处理,对研究区域进行基于栅格空间数据的土地可持续利用评价。最后总结研究区的土地可持续利用状况,提出适合研究区域土地可持续利用的可行性建议。  相似文献   
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