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51.
Wei Shoulin Xiao Rong Professor Ocean University of Qingdao Qingdao . Teaching Assistant Ocean University of Qingdao Qingdao 《中国海洋工程》1994,(1)
- In this paper, a numerical computation method is developed for the computation of current field in the tidal zone, using the well-point method and ADI method. The computational results agree well with the general variation of current field in the tidal zone. 相似文献
52.
现行黄河口水下三角洲海底形貌及不稳定性 总被引:4,自引:0,他引:4
杨作升 G.H.Keller 陆念祖 D.B.Prior 林天充 B.D.Bornhold 许卫东 L.D.Wright J.Suhayda 曹立华 W.J.Wisenman 《中国海洋大学学报(自然科学版)》1990,(1)
高分辨力的声学仪器调查表明,现行黄河口水下三角洲海底的形貌十分复杂,由于高浓度巨量黄河泥沙快速沉积的结果,使河口底坡出现了大量的不稳定性现象,如塌陷冲沟,高密度沉积物重力流,切割—充填结构海底,V形水下河谷、滑塌等。根据海底扰动程度作了分区,划分了地形单元,并对不同的海底形态的成因作了分析。比较了1985和1986年两个航次考查结果的变动,分析了原因。 相似文献
53.
ZHENG Xilai WANG Bingchen LI Yuying XIA Wenxiang Institute of Environmental Science Engineering Ocean University of Chin Qingdao Shandong Comprehensive Institute of Geotechnical Survey Beijing 《《地质学报》英文版》2004,78(3)
On the basis of site investigation and sample collection of petroleum contaminants in the soil-water-crop system in the Shenyang-Fushun sewage irrigation area, the physical-chemical-biological compositions of the unsaturated zone is analyzed systematically in this paper. At the same time, the degradation kinetics of residual and aqueous oils is determined through biodegradation tests. The studies show that dominant microorganisms have been formed in the soils after long-term sewage irrigation. The microorganisms mainly include bacteria, and a few of fungus and actinomycetes. After a 110-days' biodegradation test, the degradation rate of residual oil is 9.74%-10.63%, while the degradation rate of aqueous oil reaches 62.43%. This indicates that the degradation rate of low-carbon aqueous oil 相似文献
54.
裂缝性储层裂缝的阵列侧向测井响应数值模拟 总被引:1,自引:0,他引:1
为了研究裂缝性储层裂缝的阵列侧向测井响应, 采用裂缝组平板裂缝模型, 利用三维有限元方法, 进行不同裂缝参数条件下的高分辨率阵列侧向测井响应数值模拟.表明阵列侧向视电导率和裂缝孔隙度与裂缝流体电导率成线性关系; 低角度裂缝的阵列侧向深浅视电阻率呈现负差异特征, 高角度缝呈现正差异; 相同裂缝孔隙度下, 裂缝密度增加可使得阵列侧向视电阻率增加, 当裂缝密度足够大时, 测井响应特征基本不随裂缝密度发生变化; 交叉缝的测井响应与具有相同角度的平行裂缝组差异明显, 且不同倾角组合的交叉缝的测井响应之间差异明显.阵列侧向测井对裂缝有较强的敏感性, 根据其测井视电阻率大小可以评价裂缝孔隙度, 根据深浅视电阻率的幅度差异可以研究裂缝的产状, 这些为将阵列侧向测井用于裂缝性储层裂缝评价有指导意义. 相似文献
55.
ZHANG Shuhua YU Yifa LI Benxia Associate Professor Ocean University of Qingdao Qingdao P. R. China. Master Ocean University of Qingdao Qingdao P. R. China. 《中国海洋工程》1998,(2)
Marine structures operating in natural ocean environment are subjected to various stochasticloads.For design of the marine structures,the most important task is to determine environmental load de-sign criterion.This paper presents a method to determine the optimum environmental load design criteri-on for marine structures.This method is based on the investment and benefit analysis and it can reach thedesign purpose of decreasing total costs during the service life of the structures and increasing economicbenefits. 相似文献
56.
华北克拉通北缘西段中元古代花岗岩类的特征及其形成构造环境 总被引:3,自引:0,他引:3
华北克拉通北缘西段中元古代花岗岩类仅见于查干础鲁-霍尔森构造带以南的雅布赖-巴音诺尔公构造带中,整体上受NEE向长寿命线性构造控制。据岩性可分为斜长花岗岩和石英闪长岩两类。斜长花岗岩为S型花岗岩,但具有向I型过渡的特征,富含Cr,Ni,SiO2,Al2O3,其均值分别为672μg/g,405μg/g,71.40%和14.93%。δEu值变化大,介于0.34和3.95之间,起源于幔源岩浆与壳源物质的混合。石英闪长岩为典型的I型花岗岩,其Cr,Ni含量的均值分别为220μg/g和162μg/g,类似于华南同熔型花岗岩。斜长花岗岩中的锆石U-Pb等时线上交年龄为1256Ma,代表了发生于华北克拉通北缘西段的一次构造-热事件。伴随这一构造-热事件,华北克拉通北缘西段发生拉伸裂解,进入拉张型过渡壳阶段。中元古代花岗岩类是这一构造热事件的重要产物。在这一构造-热事件中,推测查干础鲁-霍尔森一线地壳减薄最大,其北侧的宗乃山-沙拉扎山构造带因无同时代岩浆作用,为非火山型被动陆缘,南侧的雅布赖-巴音诺尔公构造带广泛发育了花岗岩类,镁铁质、超镁铁质侵入岩,以及火山-沉积组合,为火山型被动陆缘,二者构成被动陆缘“对”。 相似文献
57.
Proteins of the DYRK(dual-specificity tyrosine-phosphorylation-regulated kinase) family are characterized by the presence of a conserved kinase domain and N-terminal DH box.DYRK2 is involved in regulating key developmental and cellular processes,such as neurogenesis,cell proliferation,cytokinesis,and cellular differentiation.Herein,we report that the ortholog of DYRK2 found in zebrafish shares about 70% identity with that of human,mouse,and chick.RT-PCR showed that DYRK2 is expressed maternally and zygotica... 相似文献
58.
LIU Xuehai ZHENG Guizhen XU Delun
Graduate Student Physical Oceanography Laboratory Ocean University of Qingdao Qingdao P. R. China
Ph. D. Candidate Physical Oceanography Laboratory Ocean University of Qingdao Qingdao P. R. China
Professor Physical Oceanography Laboratory Ocean University of Qingdao Qingdao P. R. China 《中国海洋工程》1999,(4)
In light of the analysis of the physical implication and underlying assumption of the bandwidthparameterεof wave spectrum,a time-averaging method is used to evaluateεof the JONSWAP spectrum fordifferent sea states.The resulting values ofε,which vary from 0.44 to 0.53 depending on the dimensionlessfetch,are physically meaningful and reasonable.The same method is also used to computeεfrom wind-waverecords measured in a flume under different wind speeds at different fetches.The computed values ofε,which vary with wind fetches and speeds too,are compared with those evaluated for the JONSWAP spec-trum. 相似文献
59.
CHEN JiTao HAN ZuoZhen ZHANG XiaoLei FAN AiPing & YANG RenChao College of Geological Science Engineering Sh ong University of Science Technology Qingdao China School of Earth Environmental Sciences Seoul National University Seoul - South Korea 《中国科学:地球科学(英文版)》2010,(2)
Ribbon rocks are characterized by an alternation of millimeter-to centimeter-thick limestone and argillaceous deposits (marlstone or shale).The sedimentary processes and diagenetic characteristics of ribbon rocks might be critical to the formation of limestone conglomerates.According to detailed field measurement and laboratory analyses (thin section observation and XRD analysis),four types of ribbon rocks are classified,i.e.,limestone and marlstone couplet (L-M),limestone and shale couplet (L-S),thin-bedde... 相似文献
60.