饱和弹性土体中圆柱壳体对弹性波的散射

考虑土颗粒、孔隙流体的压缩性及孔隙流体与土骨架之间的粘性耦合作用,采用修正的Biot模型,研究了入射平面P1波（快压缩波）在饱和土中不透水的圆柱壳体上的散射问题, 得到了散射和折射波场势函数的幅值方程. 通过数值计算, 分析了无量纲频率及厚度对高、低硬度两类圆柱壳体的背向散射谱和动应力集中因子的影响.      

光照强度对条斑紫菜贝壳丝状体培养的影响

光照与温度对条斑紫菜(Neopyropia yezoensis)贝壳丝状体生长发育与壳孢子放散水平均具有重要影响.因温度对光强的协同效应以及各培养阶段对光强的需求不同,本文仅改变培养光强,研究了不同光照强度对条斑紫菜贝壳丝状体着生、生长、发育及壳孢子放散的影响,为育苗阶段光照强度管理提供数据支撑.在16℃下采用1.3～...     

不同卤虫卵孵化的比较研究

分别选取进口质量较好卤虫卵、进口质量较差卤虫卵、台湾产卤虫卵和天津产卤虫卵进行标准条件孵化、自然条件孵化及去壳卵孵化.结果发现,天津产卤虫卵,颜色、形状正常,每1 g卵数为19×104,孵化率最高,达94.0%.质量较差的进口卵,颜色、形状不太正常,每1 g卵数为35×104,孵化率最差.在标准和自然条件下,卤虫卵均在36h达最高孵化率,但标准条件下的孵化率高.去壳卵的孵化率最高,孵化24 h时,最高孵化率达96.8%比标准条件孵化时快近12 h.但去壳卵易结团或结块下沉,不易漂浮.     

硇洲岛潮间带不同生境底栖软体动物物种多样性研究

对硇洲岛潮间带（岩石、砾石、泥沙滩）3种不同生境的11个样方的底栖软件动物进行了生物多样性调查，共鉴定底栖软体动物21科41种。研究结果表明，硇洲岛潮间带底栖软体动物动物种丰富度指数砾石滩最大（平均为9.236)，岩石滩次之（平均为6.494)，泥沙滩最小（平均为3.788)，多样性指数砾石滩（平均为2.154)大于泥沙滩（平均为1.506）大于岩石滩（平均为1.334)。对上述样方进行聚类分析的结果表明，底栖软体动物的种类及数量分布受底质、浪击、污染等因素的影响。     

纳米Cu2O/珍珠贝壳复合材料的光催化杀菌机理研究

研究了纳米 Cu2O/珍珠贝壳复合光催化材料对嗜水气单胞菌、副溶血弧菌、鳗弧菌和溶藻胶弧菌的杀菌效果,并考察了材料浓度、光源强度、作用时间等因素对杀菌作用的影响.结果表明,该复合材料对四种病原菌均具有较强的杀灭能力,复合材料浓度为100 mg/L时,无论在紫外光还是太阳光下照射2 h,杀菌率均达到100%; Fe (phen)32+光度法验证了复合材料溶液在光照过程中产生了具有强氧化活性的自由基.     

Dynamic Structure-Fluid Interaction Response of a Composite Cylindrical Shell Submerged in Water

This paper analyzes the dynamic structure-fluid interaction response of a submerged compo-site cylindrical shell.Dynamic equations based on the first-order shear deformation theory include the ini-tial stresses and structure-fluid interaction forces due to fluid.The field equation is solved by expandingthe velocity potential into series similar to transverse deflection of the cylindrical shell and thestructure-fluid interaction force is obtained.The dynamic response is investigated by means of series expan-sion method.The effects of structure-fluid interaction on dynamic response are discussed.     

生物壳体锶地球化学恢复盆地古水文——以泥河湾盆地为例

本文以著名的泥河湾盆地小渡口剖面28层为实例,通过有孔虫,介形虫,腹足类微体生物壳体87Sr/86Sr比值与盆地汇水区域Sr同位素地层分布特征对比分析以及生物壳体Sr/Ca国度的相关性,来重塑沉积盆地汇水来源变更,湖水变化等古水文要素,进而可以反演区域构造－气候变化,实例研究结果表明,生物壳体87Cr/86Sr 及Sr/Ca比值等地球化学方法是恢复盆地古水文条件的重要手段。     

基于OpenSees的巨型SRC柱低周反复试验数值分析

为研究巨型SRC柱抗震性能的数值模拟方法,本文基于有限元分析软件OpenSees,采用纤维单元模拟5根具有不同复杂截面型钢形式的巨型SRC柱试件的低周反复加载试验,并与试验滞回曲线以及骨架曲线进行对比分析。结果表明,该基于纤维单元的有限元模型能够较好模拟巨型SRC柱试件的滞回反应,具有一定的合理性和可靠性。同时采用一种新型高性能分层壳单元对其中一根巨型SRC柱试件进行精细有限元建模分析,分析结果与试验结果对比表明分层壳能够较好地模拟试件的初始刚度和峰值承载力;与纤维单元模拟结果对比表明纤维单元能够更好地模拟试件承载力的下降,结果更加精确,且计算效率更高;新型高性能壳单元DKGQ能够弥补原有壳单元的不足,更好地模拟构件因混凝土大量开裂剥落导致的承载力下降。     

环肋椭圆柱壳-流场耦合系统自由振动的解析求解方法

提出了分析环肋椭圆柱壳-流场耦合系统自由振动的一种解析求解方法。环肋通过"刚度均摊"到均质椭圆柱壳体上,考虑流场对壳体振动特性的影响,通过Helmholtz方程描述声介质的波动,建立环肋椭圆柱壳-流场耦合系统的自由振动方程,进而求得耦合系统的自由振动固有频率。为了验证方法的准确性,将水下环肋椭圆柱壳退化成水下环肋圆柱壳和不加肋的水下椭圆柱光壳,两个退化模型的计算结果与已有文献结果吻合良好。并详细讨论了椭圆度、环肋间距等主要参数对耦合系统自由振动特性的影响。     

Ecology of Pinnidae (Mollusca: Bivalvia) from the Gulf of Thailand

The ecology of the family Pinnidae was studied by sampling three pinnid species from 36 sampling sites across four different microhabitats in the Gulf of Thailand. The species spatial distributions were mostly uniform, with some populations having random distributions. Species abundances differed between sandy and coral habitats according to non-metric multi-dimension scaling analyses. Although the Gulf of Thailand is a relatively small geographic area, habitats are varied enough to provide variable shell densities. Small islands are important distribution areas, and coral reefs provide both direct and indirect shelter which support high abundances, densities and increased shell size. The highest density was recorded in sand beds within coral reefs. Low density and small shell size in sand beaches might be related to high mortality in shallow water or to adaptations for survival in shallow waters. A clear correlation between sediment composition and species abundance was found in Pinna atropurpurea; abundance increased with the sand content of the sediment. For P. deltodes, abundance increased as the rock fraction of the sediment increased. These results suggest that adaptations in Pinnidae, such as shell size, shell morphology, and the exposure of the shell above the sediment-water interface, are responses for survival in different habitats.