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91.
运用区域地面地质、地震、钻测井等资料的综合分析,对库车坳陷中生界的盆地结构、构造样式、中生界各层序原始地层厚度和沉积相分布、古隆起形态、区域构造演化等方面进行研究,重建了库车坳陷中生代盆地构造古地理,并对盆地原型成因进行分析。库车坳陷残留中生界总体上为北厚南薄、北剥南超的地质结构,北部强烈角度不整合在南天山海西期褶皱带,南部微角度不整合面在寒武-奥陶系之上,南部边缘沿着温宿-西秋-牙哈古隆起有基底断裂活动。北部单斜带为冲积扇和辫状河三角洲,克拉苏构造带为深湖,南部沿着古隆起带为缓坡三角洲、浅湖。库车坳陷中生代原型盆地位于南天山海西期造山带和塔里木克拉通边缘过渡带之上,地壳均衡可能是盆地沉降的主要动力。南缘古隆起带在南天山洋扩张期为塔里木克拉通台地与被动大陆边缘的台地边缘,南天山洋闭合期为前陆隆起带,发育基底断裂和断块差异活动,在中生代有继承性活动,晚新生代新天山挤压隆升使古隆起带发生挤压变形,成为新天山逆冲变形造山楔的前锋。 相似文献
92.
主要研究了原地栖息真菌Talaromyces flavus作用下不同粒径的蛇纹石矿物粉末的风化作用。蛇纹石矿物粉末被筛分为不同粒度的4组(150~300、100~150、75~100和45~75μm)后进行真菌溶蚀实验,并使用p H计、ICP-OES、FTIR、XRD、SEM对反应产物进行了分析。结果表明,真菌作用显著加快了蛇纹石矿物的溶蚀,当蛇纹石矿物粒度降低到100μm左右时,Mg的溶出率从21.56%明显增加到35.91%。该现象可能与矿物比表面积的增大以及生物物理作用的增强有关。在此基础上粒径进一步减小并未使Mg溶出率明显提高,因此该粒径可以作为真菌对蛇纹石溶解工业化应用的最优粒径。扫描电镜观察与矿物相分析表明,反应过程中真菌分化产生的菌丝与矿物紧密接触,破坏了矿物的晶体结构,导致矿物相的改变。该研究结果可为相关菌种在浸矿等工业领域上的应用提供参考依据。 相似文献
93.
Application research of enhanced in-situ micro-ecological remediation of petroleum contaminated soil 下载免费PDF全文
ZHANG Sheng ZHANG Cui-yun HE Ze CHEN Li ZHANG Fa-wang YIN Mi-ying NING Zhuo SUN Zhen-hua ZHEN Shi-jun 《地下水科学与工程》2016,4(3):157-164
Experimental study of enhanced in-situ micro-ecological remediation of petroleum contaminated loess soil was carried out in Zhongyuan oil production areas, and the enhanced in-situ micro-ecological remediation technique includes optimistic in-situ microbial communities, physical chemistry methods, alfalfa planting and regulation of soil environmental elements. Experiments showed that the oil content in the contaminated soil with oil content about 2 898.25 mg/kg can be reduced about 98.61% after in-situ micro-ecological remediation for 99 days, which demonstrated the effectiveness of in-situ micro-ecological remediation methods for petroleum contaminated soil in central plains of China, and explored the practical and feasible application of these methods. 相似文献
94.
Adopting the quasi-three-dimensional (Quasi-3D) numerical method to optimize the anti-freeze design parameters of an underground pipeline usually involves heavy numerical calculations. Here, the fitting formulae between the safe conveyance distance (SCD) of a water pipeline and six influencing factors are established based on the lowest water temperature (LWT) along the pipeline axis direction. With reference to the current widely used anti-freeze design approaches for underground pipelines in seasonally frozen areas, this paper first analyzes the feasibility of applying the maximum frozen penetration (MFP) instead of the mean annual ground surface temperature (MAGST) and soil water content (SWC) to calculate the SCD. The results show that the SCD depends on the buried depth if the MFP is fixed and the variation of the MAGST and SWC combination does not significantly change the SCD. A comprehensive formula for the SCD is established based on the relationships between the SCD and several primary influencing factors and the interaction among them. This formula involves five easy-to-access parameters: the MFP, buried depth, pipeline diameter, flow velocity, and inlet water temperature. A comparison between the analytical method and the numerical results based on the Quasi-3D method indicates that the two methods are in good agreement overall. The analytic method can be used to optimize the anti-freeze design parameters of underground water pipelines in seasonally frozen areas under the condition of a 1.5 safety coefficient. 相似文献
95.
Wei-yue Li Chun Liu Yang Hong Xin-hua Zhang Zhan-ming Wan Manabendra Saharia Wei-wei Sun Dong-jing Yao Wen Chen Sheng Chen Xiu-qin Yang Yue Yue 《山地科学学报》2016,13(7):1275-1285
Landslide inventory plays an important role in recording landslide events and showing their temporal-spatial distribution. This paper describes the development, visualization, and analysis of a China's Landslide Inventory Database (CsLID) by utilizing Google’s public cloud computing platform. Firstly, CsLID (Landslide Inventory Database) compiles a total of 1221 historical landslide events spanning the years 1949-2011 from relevant data sources. Secondly, the CsLID is further broken down into six zones for characterizing landslide cause-effect, spatiotemporal distribution, fatalities, and socioeconomic impacts based on the geological environment and terrain. The results show that among all the six zones, zone V, located in Qinba and Southwest Mountainous Area is the most active landslide hotspot with the highest landslide hazard in China. Additionally, the Google public cloud computing platform enables the CsLID to be easily accessible, visually interactive, and with the capability of allowing new data input to dynamically augment the database. This work developed a cyber-landslide inventory and used it to analyze the landslide temporal-spatial distribution in China. 相似文献
96.
CHU Yingjia SHENG Lifang LIU Qian ZHAO Dongliang JIA Nan KONG Yawen 《中国海洋大学学报(英文版)》2016,15(4):569-576
The number concentrations in the radius range of 0.06 – 5 μm of aerosol particles and meteorological parameters were measured on board during a cruise in the South China Sea from August 25 to October 12, 2012. Effective fluxes in the reference height of 10 m were estimated by steady state dry deposition method based on the observed data, and the influences of different air masses on flux were discussed in this paper. The number size distribution was characterized by a bimodal mode, with the average total number concentration of(1.50 ± 0.76)×10~3 cm~(-3). The two mode radii were 0.099 μm and 0.886 μm, both of which were within the scope of accumulation mode. A typical daily average size distribution was compared with that measured in the Bay of Bengal. In the whole radius range, the number concentrations were in agreement with each other; the modes were more distinct in this study than that abtained in the Bay of Bengal. The size distribution of the fluxes was fitted with the sum of log-normal and power-law distribution. The impact of different air masses was mainly on flux magnitude, rather than the shape of spectral distribution. A semiempirical source function that is applicable in the radius range of 0.06 μmr_(80)0.3 μm with the wind speed varying from 1.00 m s~(-1) to 10.00 m s~(-1) was derived. 相似文献
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99.
This paper examines city growth patterns and the corresponding city size distribution evolution over long periods of time using a simple New Economic Geography(NEG) model and urban population data from Canada. The main findings are twofold. First, there is a transition from sequential to parallel growth of cities over long periods of time: city growth shows a sequential mode in the stage of rapid urbanization, i.e., the cities with the best development conditions will take the lead in growth, after which the cities with higher ranks will become the fastest-growing cities; in the late stage of urbanization, city growth converges according to Gibrat′s law, and exhibits a parallel growth pattern. Second, city size distribution is found to have persistent structural characteristics: the city system is self-organized into multiple discrete size groups; city growth shows club convergence characteristics, and the cities with similar development conditions eventually converge to a similar size. The results will not only enhance our understanding of urbanization process, but will also provide a timely and clear policy reference for promoting the healthy urbanization of developing countries. 相似文献
100.