Wave Reflection Caused by Wave Overtopping and Sloping Top of Spructure

In this paper, the theoretical analysis and experimental studies are employed to investigate the reflection characteris-tics of partial standing waves caused by wave overtopping and sloping top of structures. Based on the principle of conser-vation of wave energy flux, the third-order Stokes wave theory is used to formulate the reflection coefficient at wave overtopping; the calculation results are regressed into an applied expression. A series of experiments of wave reflection for a vertical-wall structure with chamfered and overhanging upper sections are carried out to investigate the influence of top slope on wave reflection. The regularity of variation of wave reflection in this case is analysed based on the experimental results.     

台湾海峡1997年8月至1999年8月份海水光学衰减系数的分布特征

利用1997－1999年间8月份台湾海峡的实测资料，分析了海水光学衰减系数的垂直分布类型、水平分布特征。结果表明，台湾海峡海水光学衰减系数的垂直分布类型主要分为5种，大部分随深度而递增；光学衰减系数等值线基本与岸线平行，水平梯度自北向南、自近岸向外海递减，近岸等值线密集，而外海稀疏；影响台湾海峡光学衰减系数的主要因素是县浮物质（主要含浮游生物）和海流运动。     

Hilbert Transferin Applied to Separation of Waves

The analytical method (AM) for separation of composite waves is presented based on the Hilbert transform. It is ap-plicable to both regular and irregular trains of waves. The wave data series measured with two wave gauges in the experi-ments are separated into two series of incident and reflected waves. Then, the reflection coefficient can be easily ob-tained. The arrival of reflected waves can also be detected for improveraent of the accuracy of the reflection coefficient. The reflection performance of the physical model can be estimated exactly without calculation of wave height and phase difference. Numerical samples developed to test the method are proved to be accurate. Physical experiments are conduct-ed and compared with Goda s method and satisfactory results are obtained.     

钝顶螺旋藻C-藻蓝蛋白和多管藻R-藻红蛋白的分离纯化及摩尔消光系数的测定

１９９３年１１月～１９９４年１月用简单的羟基磷灰石柱层析法从多管藻中分 离纯化了Ｒ－藻红蛋白和从钝顶螺旋藻中纯化了Ｃ－藻蓝蛋白，它们的纯度（指可见 光部分的最大吸收与 ２８０ｎｍ处吸收值之比）可分别达到 ６（Ｒ－藻红蛋白）和 ５． ５（Ｃ－ 藻蓝蛋白）。由于不同藻种的同种藻胆蛋白的摩尔消光系数不同，所以应用凯氏定 氮法并结合可见光的吸收值测定了上述两种藻胆蛋白的摩尔消光系数，钝顶螺旋 藻Ｃ－藻蓝蛋白为１．８５３ × １０６ｍｏｌ－１ｃｍ－１（６２０ｎｍ），多管藻Ｒ－藻红蛋白为１．７９６ × １０６ｍｏｌ－１ｃｍ－１（４９８ｎｍ），为藻胆蛋白的浓度测定提供了方便。     

Nutrient attenuation in a shallow,gravel-bed river. II. Spatial and temporal changes in nitrogen dynamics and community metabolism

ABSTRACT

Instream processes alter the concentration and bioavailability of nutrients as they are transported downstream. By relating primary production and periphyton composition to changes in nutrient concentration in a gravel-bed river this study made inferences about recycling and attenuation. Where dissolved inorganic nitrogen (DIN) was abundant, concentrations decreased linearly with distance but by less than required to meet the nitrogen demand of primary production. Where DIN was barely measurable photosynthesis was reduced but only by 50%. We infer that recycling sustained primary production even when DIN concentrations were negligibly small. One implication is that DIN removal underestimates attenuation. Further experimental research on recycling and improved modelling is required to better quantify the length of streams adversely affected by nutrients.     

厦门湾有色溶解有机物的光吸收特性研究

研究了厦门湾九龙江河口区、西海域、同安湾及东侧水道海水中有色溶解有机物(CDOM)的光吸收特性,分析了CDOM的河口行为,并讨论了CDOM光吸收特性与其荧光性质之间的关系。结果表明,厦门湾表层海水CDOM光吸收系数a(355)的水平分布表现为河口区最高、东侧水道最低、西海域和同安湾介于两者之间,底层水a(355)的分布与表层基本相似,表明陆源河流输入是厦门湾CDOM的主要来源;a(355)的垂直分布为表层高于底层,主要受水文和生物因素控制。厦门湾表层水CDOM光谱斜率S的平均值介于0.014—0.018nm-1,但河口低盐度区S值较小,反映陆源腐殖质的影响。a(355)在河口混合中呈保守行为,表明CDOM具有良好的保守性质。CDOM的吸收系数a(355)与其荧光强度之间表现为较好的相关关系,指示可以用灵敏度更高的荧光方法来研究CDOM的分布和行为。     

Effects of Irregular Wave Groups on Pile Forces

The wave forces on 1, 2 and 4 vertical circular piles under the action of several wave trains of the same wave parameters, such as Hs,Tp and Mo, but different wave group factor GF are measured in the laboratory. After comparing these forces, it may be concluded that the mean and significant wave forces are almost of no difference for the wave trains with different GF. When GF is larger, the one-tenth of the wave froce extreme is slightly increased and the maximum wave force is much larger than the ones with smaller GF, to which attention must be paid in engineering practice.     

煤炭资源勘查误差理论研究

对煤炭资源勘查资源量与客观物质量之间差值的误差理论探讨,提出误差由真值误差、系统误差和离差3个基本部分组成,其中真值误差是不可消除的观测误差、系统误差是控制网度所决定的准确度标准、而离差是由地质构造及矿床形态的多解性产生的资源量波动。在此基础上,构筑了一个关于误差的数学模型,最后应用误差理论对现行勘查工作中常见的错误进行分析,并就如何避免错误及减少误差提出了见解。     

垦71区块井间地震资料处理研究与应用

由于避开了地表低降速带和风化层的影响,井间地震能够采集到高频地震信号,经过资料处理可以得到较高分辨率的速度和上行反射波成像剖面。2004～2005年,胜利油田在垦71 区块实施了8对井间地震资料采集。针对原始资料特点,研究了以层析成像、管波衰减、VSP-CDP技术和有限角度叠加成像等关键处理技术,较好地完成了该区块的井间地震资料处理。初步分析解释表明,井间地震可以识别低序级断层、小幅度构造和薄储层。     

潜水蒸发系数综合分析

利用河北省冉庄水资源实验站、安徽省五道沟水文水资源实验站、山西省太谷均衡实验站实测的潜水蒸发资料,对潜水蒸发及潜水蒸发系数的变化规律进行了综合分析。提出了不同岩性、不同潜水埋深在有无作物生长条件下的潜水蒸发系数。为华北地区水资源平衡计算潜水蒸发系数的选定提供了参考数据。