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941.
MA Ruijie LI Xin. College of Mathematics Jilin University Changchun China . College of Construction Engineering China 《东北亚地学研究》2009,(3):164-167
The underground water quality model with non-linear inversion problem is ill-posed, and boils down to solving the minimum of nonlinear function. Genetic algorithms are adopted in a number of individuals of groups by iterative search to find the optimal solution of the problem, the encoding strings as its operational objective, and achieving the iterative calculations by the genetic operators. It is an effective method of inverse problems of groundwater, with incomparable advantages and practical significances. 相似文献
942.
943.
?о?InSAR?α????????????????Kriging????????????????????????????1996??????SAR???????????????????е????????????????÷???????Ч?????α???????????????????????????????? 相似文献
944.
Abalone Haliotis diversicolor supertexta is an important economic mollusk.The settlement and metamorphosis are two critical stages during its development period,which has direct influence on abalone survival and production.The influence of reactive oxygen species(hydrogen peroxide) on abalone embryo and juvenile development were examined in this study.Larvae of Haliotis diversicolor supertexta were induced to settlement and metamorphose by exposure to seawater supplemented with hydrogen peroxide.They had the best performance at 800 μmol/L.The concentration of 1 000 μmol/L or higher was toxic to the larvae,as the larvae could settle down only at benthic diatom plates without complete metamorphosis.In addition,H2O2 adding time was critical to the larval performance.24h after two-day post-fertilization was proved to be the optimal adding time.In this paper,two action mechanisms of hydrogen peroxide are discussed:(1) hydrogen peroxide has direct toxicity to ciliated cells,thus cause apoptosis;(2) hydrogen peroxide,as a product from catecholamines' autoxidation process in vivo,can reverse this process to produce neuro-transmitters to induce abalone metamorphosis. 相似文献
945.
Log evaluation of fractured igneous reservoirs in Songliao Basin 总被引:1,自引:0,他引:1
Baozhi PAN Lihua ZHANG Ying ZHANG Chen HUANG 《东北亚地学研究》2007,10(1):65-68
The petrophysical parameters are bad in most igneous reservoirs of Songliao Basin because of the very low porosity and permeability. The evaluation of igneous reservoirs has not been fully studied so far. The current technique of formation evaluation and interpretation used in sedimentary formations face a series of prob- lems and difficulties. In this study, The PCA was used to identify lithology, a multi-mineral model “QAPM” was proposed. “Surface effect” must be considered when evaluating saturation. A software “SIMPLE” was developed and was used to deal with the logging data in over 70 wells with good results were achieved. 相似文献
946.
Caikun GAO Huakun DU Jingtian TANG Kangxiu WU Chang'an XIAO Shiping WANG 《东北亚地学研究》2008,11(3):191-196
Integrated geophysical interpretation is a method of combinating different geophysics prospecting methods based on different physical properties of accumulation. As different geophysical methods own different interpretations and varying detection accuracies, the key issue becomes how to integrate the results of several geophysical methods to corrently carry out a comprehensive explanation. Based on different geophysical results, the authors proposed an integrated geophysical explanation method and successfully applied it in practical engineering problems. 相似文献
947.
WANG Bin QIU Jianhui ZHAO Dong YANG Xi DAI Shuai.College of Construction Engineering Jilin University Changchun China .Design Institute of Jilin Architectural Civil Engineering Institute Changchun China 《东北亚地学研究》2009,12(1):28-31
The finite element method was used for analysis of raft foundation design in high-rise building. Compared with other conventional methods, this method is more adapted to the practical condition since both superstructure stiffness and soil conditions were considered in calculation. The calculation results by example show that the base reaction is more uniform and the maximum reaction decreases obviously. Accordingly, the raft foundation design is more economic without any loss of security for high-rise building. 相似文献
948.
Dajun ZHAO Guosheng JIANG Youhong SUN Junhua ZHENG Zhuwen WANG .Faculty of Engineering China University of Geosciences Wuhan China.College of Construction Engineering Jilin University Changchun China.College of Geoexploration Science Technology China 《东北亚地学研究》2008,11(4):228-231
A high efficiency method is very important in geological survey for a new city in China. Geophysical parameters are Measured While Drilling (MWD), and these parameters are processed and explained on the ground, so the method can replace conventional engineering geological exploration for drilling rock sample. According petroleum engineering MWD, using the different characters of different rock absorbs γ radial, with the method of storing data in hole and explaining data on the ground, engineering geological exploration formation density MWD is researched. The MWD works stabilized, and the performance is good with precise data. 相似文献
949.
Chengdong QI Guohua QIAO Hongchen DONG Dayei LUI Xing ZHANG Deli YU .Regional Survey of Geology & Mineral Resources Jilin Province Changchun China.College of Material Science Engineering Jilin University Changchun China 《东北亚地学研究》2008,11(4):214-217
LA-ICP MS zircon U-Pb dating results of granites from Sawuer Mountains in North Xinjiang, NW China, are reported based on 1:50 000 regional geologic surveys. Zircon U-Pb dating shows that the granitoids have magmatic crystallization age of 320 ± 2 Ma. In addition, zircons with ages of 341 -358 Ma could be subdivided into two groups, i. e. , Group 1 with a weighted mean age of 342 ± 3 Ma and Group 2 with a weighted mean age of 354 ± 2 Ma. The petrology and geochemistry of granitoids from Sawuer Mountains suggest their mixed origin. The granite from Sawuer Mountains occurred in an extensional setting, most probably related to post-orogenic processes during the closure of the Peo-Asian Ocean ; namely, represent the tectonic setting shifted from compress to post-collisional setting. 相似文献
950.