Dynamic Response Behaviors of Upright Breakwaters Under Breaking Wave Impact

- The dynamic response behaviors of upright breakwaters under broken wave impact are analysed based on the mass-damper-spring dynamic system model. The effects of the mass, damping, stiffness, natural period, and impulse duration (or oscillation period) on the translation, rotation, sliding force, overturning moment, and corresponding dynamic amplifying factors are studied. It is concluded that the ampli-ying factors only depend on the ratio of the system natural period to impulse duration (or oscillation period) under a certain damping ratio. Moreover, the equivalent static approach to breakwater design is also discussed.     

人工养殖点带石斑鱼弧菌病病原菌的分离及鉴定

广东、海南两省多个海水网箱养殖场养殖的点带石斑鱼(Epinephelus malabaricus)发生严重的弧菌病,从海南三亚和广东深圳的发病鱼病灶上分离到2株致病性细菌VAL02和VAL00,经人工回接感染实验证明这2株菌引起点带石斑鱼弧菌病,VAL02对点带石斑鱼苗的半致死量是2.25×10~5 cfu/g。经形态及生理生化特征分析,鉴定出VAL02及VAL00均为溶藻弧菌。应用药敏纸片法研究了22种化学疗剂对VAL02及溶藻弧菌标准株的生长抑制作用,发现VAL02对氯霉素、氟哌酸、卡那霉素和乙酰螺旋霉素等产生耐药性,对复方新诺明和环丙沙星等敏感。     

海洋作业渔船管理系统的设计与运行试验

对渔政管理指挥系统建设项日中的业务软件部分渔船管理系统的设计方案进行了介绍。根据我国渔洋作业渔船的实际管理模式，提出了渔船管理系统设计方案。系统通过网络化的业务处理和管理流程，规范渔船建造、审批、登记以及捕捞许可证发放等管理业务，实现渔船控制指标的统一分配，以控制捕捞业发展规模和保护我国的渔业资源。系统以Microsoft VB6．0，Delphi6．0开发，在Window98／2000／XP环境下运行。通过运行试验，对系统运行环境进行了评估，为渔政管理信息化的建设、系统升级提供了经验和技术依据。     

华北板块北缘东段陆缘活动带构造岩片划分及变质变形特征

1∶25万和龙市幅、汪清县幅等九幅区域地质调查成果显示,华北板块北缘东段残存着数条元古代-古生代不同时期的构造岩片,这些构造岩片均经历了强烈的变形改造及变质作用叠加,记录了增生型造山带在不同演化阶段热-动力学条件。吉林东部华北板块北缘陆缘活动带东段内元古代-古生代构造地层单位的确定,对探讨吉黑地区的大地构造演化具有重要意义。     

便携式电子地图设计中需解决的几个问题

软性显示器和投影技术超微型化的发展,使得电子地图有足够的空间满足便携式电子地图的设计需求,本文通过介绍几种便携式材质的特性,提出便携式电子地图设计中需解决的几个硬件技术问题。     

制图综合中移位算法概述分析

本文首先对移位算法的发展史进行简要介绍,然后,在其基础上,根据各移位算法的思想特征,对各移位算法进行归纳,将其划分为七类,并对每一类算法的核心思想进行详细论述,最后,对各类移位算法进行评价,分析其优缺点,总结各类算法中的可借鉴思想,为更好地实现移位奠定基础。     

Benthic nutrient fluxes in the intertidal flat within the Changjiang （Yangtze River） Estuary

In an annual cycle from March 2005 to February 2006, benthic nutrient fluxes were measured monthly in the Dongtan intertidal flat within the Changjiang （Yangtze River） Estuary. Except for NH4^＋, there always showed high fluxes from overlying water into sediment for other four nutrients. Sediments in the high and middle marshes, covered with halophyte and consisting of macrofauna, demonstrated more capabilities of assimilating nutrients from overlying water than the low marsh. Sampling seasons and nutrient concentrations in the overlying water could both exert significant effects on these fluxes. Additionally, according to the model provided by previous study, denitrification rates, that utilizing NO3- transported from overlying water （Dw） in Dongtan sediments, were estimated to be from -16 to 193 μmol·h^-1·m^-2 with an average value of 63 μmol·h^-1·m^-2 （n=18）. These estimated values are still underestimates of the in-situ rates owing to the lack of consideration of DN, i.e., denitrification supported by the local NO3^- production via nitrification.     

Changes in nutrient uptake of phytoplankton under the interaction between sunlight and phosphate in the Changjiang （Yangtze） River Estuary

We conducted ship-board incubation experiments to investigate changes in nutrient uptake of phytoplankton under different phosphate concentrations and irradiances in the Changjiang River Estuary and its adjacent waters in China. Under 100% natural irradiance the uptake rates of phosphate, silicate, and nitrate were accelerated at high phosphate levels （1.84 μM）, while under low irradiance （about 50% natural irradiance） their uptake rates were restrained at the high but stimulated greatly at the intermediate phosphate concentrations （1.26 μM）, as the growth of phytoplankton, changes in nitrite and ammonium uptake didn＇t follow an obvious pattern. Our results also showed that there were linear relationships between nitrate, silicate and phosphate uptake at different phosphate concentrations under low and high irradiances, and the growth period of phytoplankton was prolonged both at the high phosphate concentrations under high irradiance and at the intermediate concentrations under low irradiance, suggesting that the limitation of phytoplankton growth mainly reflected changes in its growth period, and because no such environment （low irradiance and low phosphate concentrations） actually existed in a high turbidity zone, phytoplankton blooms hardly occurred there. In the absence of irradiance, denitrification occurred readily and phytoplankton was kept decreasing, which resulted in phosphate regeneration.     

大兴安岭白音诺尔铅锌矿控矿构造研究与找矿预测

成矿物质来源及控矿因素是矿床学研究的前沿课题。过去人们认为成矿物质主要源于含矿围岩的萃取。因此,找矿重点是寻找矿源层。但是,更多的事实表明,成矿物质主要来自深源,通过地幔热柱多级演化迁移至地壳,并在幔枝构造较好的控矿构造空间聚集成矿。本文探讨了大兴安岭中南段的成矿作用,总结了该区的主要控矿构造,指出了不同级别构造对成矿的控制作用,并预测了不同级别的成矿靶区。     

Multiple Volcanic Episodes of Flood Basalts Caused by Underplating

Most Large igneous provinces (LIPs) are emplaced within <10 Ma, with a main pulse of the magmatism in<1 Ma[1]. For example, the Siberian Traps [2] and the Deccan Traps [3] were probably erupted within one million years. Many events, such as the Columbia River event, feature a single pulse of magmatism, followed by a protrac-ted period of magmatism at a much lower rate that is linked to a plume tail[4].