邻二氮菲分光光度法测定赤泥和石灰石混匀度

用盐酸提取赤泥和石灰石的混合料后,通过邻二氮菲分光光度法测定提取液中铁含量,进而求得混合料中氧化铁的质量分数,以此来衡量混匀度。结果表明,该法与重铬酸钾法比较,精密度和准确度均无显著性差异,测定混匀度的相对误差在±2%,且方法简便、快速、准确、对环境友好,可用于生产实时监控。     

地球公转自转与地壳动力学

经典力学是有相对性的,但在地球公转自转力学和地壳构造动力学的研究中有一定可用性。地球的公转和自转是地壳构造应力的天体力源,在此力学体系中的岩体力学基本方程还须做重要改进或重建。     

基于土体细观结构的土质加固分类方法初步分析

目前的土质加固与地基处理技术,大都摒弃土体原有结构不用,或实施强力重新构造土体的结构,以耗费大量的能 量、费用为代价。基于土的细观结构,从加固体的力学特性以及加固土体的结构变化角度对地基处理类别进行三类划分、按 土体加固技术的实施路径进行二类划分,目的是更多地关注加固体与土的相互作用、重视土的结构作用。若能在加固时充分 利用土体的原有强度,在已有的土体结构形式上实施结构上的补强,在理论上将使能量使用更经济、从而节约工程造价,而且 将减少对环境的影响和扰动。     

川西绵竹地区构造特征及对油气成藏控制作用

绵竹主体构造为龙门山前构造带关口隐伏断裂的下盘构造,构造样式为研究区断滑褶皱,形成于印支期,在喜山期遭受了一定程度的调整改造,为一古今叠合构造。对研究区构造特征及演化分析表明,构造形成及其演化对研究区圈闭类型、储层发育、油气运移通道有着强烈的控制作用,是绵竹构造油气成藏和富集的主要控制因素。多期构造运动形成的不整合面及断裂为油气运移提供了良好的通道,有效改善了储层孔渗条件,形成的断背斜、背斜为油气聚集成藏提供了良好的场所。     

润扬大桥悬索桥索夹定位与检测

介绍了润扬大桥悬索桥索夹定位的基本过程和方法,分析了定位过程中的误差来源及减少误差影响的方法,对实测成果进行了全面的分析.     

Large‐scale seismic tests of tall concrete bridge columns with precast segmental construction

Past experimental studies have shown that existing precast segmental concrete bridge columns possess unsatisfactory hysteretic energy dissipation capacity, which is an undesirable feature for applications in seismic regions. In this research, we propose new methods of precast segment construction for tall concrete bridge columns to enhance the columns' hysteretic energy dissipation capacity and lateral strength. This is accomplished by adding bonded mild steel reinforcing bars across the segment joints, strengthening the joint at the base of the column and increasing the height of the base segment (hinge segment). Four large‐scale column specimens were fabricated and tested with lateral cyclic loading in the laboratory. Each specimen consisted of a foundation and 9 or 10 precast column segments. Test results of specimens with the proposed design concepts showed ductile behavior and satisfactory hysteretic energy dissipation capacity. In addition to the experimental study, an analytical study using the finite element method was conducted to understand the bond conditions, strain contours and deformation patterns of the specimens tested. Good agreement was found between the experimental observations and the results of the calibrated analytical study. Copyright © 2008 John Wiley & Sons, Ltd.     

Fossil gastropods from the MGS3 stratigraphic segment in the Salawusu River Valley and their climatic and environmental implications

Contemporaneous with MIS3, the MGS3 segment of the Milanggouwan stratigraphic section in the Salawusu River Valley, Mu Us Desert, China contains fossil gastropods (terrestrial and freshwater snails) in strata 33LS, 35LS, 37FL and 39LS. Examination of these fossils revealed 11 species belonging to 8 families and 10 genera. They can be classified as: (1) assemblage of Gyraulus and Galba mainly consisting of Gyraulus convexiusculus, Gyraulus sibiricus, Galba pervia and Galba superegra Gredler, etc. (2) assemblage of Vallonia mainly consisting of terrestrial snails, such as Vallonia patens, Pupilla muscorum and Discus paupe, etc. Based on the dating results, and the living habits, living conditions, and geographic distribution of their extant species, we suggest that: the ages of 33LS, 35LS, 37FL, and 39LS are 26000, 29000, 33000 and 38000 a, respectively, corresponding well to the interstadial period in GRIP 4, 5, 6 and 10 in terms of chronology and climatic characters; 33LS, 35LS and 39LS represent very warm-humid periods, while 37FL represents a less warm-humid period; the four periods of climatic fluctuations recorded in MGS3 were related to the strong impact of the summer monsoon in East Asia in Mu Us Desert of China during the interstadial of MIS3 on a global climatic background.     

海带雄配子体单性生殖叶状体的特性

海带雄配子体经单个分离培养,长成丝状体细胞,这些细胞体积逐渐增大,由单性生殖直接发育成叶状体.这种叶状体的畸形率达93 3%,将叶状体养殖在海上,能长成大海带,但它们都不能成熟.这些叶状体在同一克隆遗传特性十分一致,不同克隆则存在明显差异.     

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