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121.
In order to verify the effectiveness of electrolytic treatment on ships' ballast water,experiments are carried out by a pilot system in laboratory. The raw seawater and seawater with different concentrations of different algae are simulated as ships' ballast water. The algae in the raw seawater can be killed if it is treated by electrolysis with an initial residual chlorine concentration of 5 mg/L. If the seawater with one kind of algae (Nitzschia closterum, Dicrateria spp., or Pyramidomonnas sp.105cells/mL) is treated by electrolysis with an initial residual chlorine concentration of 5 mg/L, the alga can be sterilized. If the seawater with one kind of algae (Dunaliella sp., Platymonas or Chlorella spp.)is directly treated by electrolyzing with an initial residual chlorine concentration of 4 mg/L, the instant mortality changes with the concentration of different algae. However, after 72 hours, in all treated samples, there are no live algal cells found.  相似文献   
122.
赵楠  沈晋明 《船舶》2007,(3):58-60
研究了国内外海上医院船的发展动态,尤其是海上医院手术部气流组织的特点.对手术部医疗环境、卫生环境与舒适环境控制寻找一种合适的净化空调与自控系统作了详细地介绍,提出了解决该问题的途径及方法.供深化设计参考.  相似文献   
123.
The ballast water from ships carries marine organisms that have invasive potential. The International Maritime Organization Ballast Water Management Convention (2004) requires ballast water exchange or ballast water management (BWM) systems either onboard or ashore. Ships can be exempted on the basis of risk assessment, when exclusively sailing between specific ports or in an enclosed area. In reply to our questionnaire, the shipping sector argues that the North Sea is ecologically homogeneous and exemptions could therefore be granted. This paper proposes that the North Sea area is, in fact, not homogeneous in terms of hydrographical and biological conditions; therefore, ballast water is a relevant transport mechanism for organisms. Within the North Sea, the short shipping routes indicate a high risk for survival. We examined actual simulation models for ballast water risk assessment in the North Sea, and we have identified the major parameters that need to be included in such models. These models provided a basis; they further need to be combined and adapted for the purpose of evaluating the rationale for an exemption. We concluded that exemptions from BWM are not recommended for the North Sea area. Anticipating the Ballast Water Management Convention, ship owners might do well to study possibilities for installing BWM systems onboard.  相似文献   
124.
压载系统是半潜船的关键性系统,设计需要满足半潜船潜装、滚装和吊装等多种装卸货方式的要求。为此以中远航运50 000 DWT半潜船为例,介绍半潜船压载系统的设计要点。包括半潜船上浮时间的确定、半潜船常用排/压载方式的选择、大型排/压载设备的介绍、压载系统的设计和优化以及压载系统满足BWM公约D-2规则要求的研究等。  相似文献   
125.
船舶压载水的处理与进展   总被引:1,自引:0,他引:1  
船舶压载水的随意排放是造成外来生物入侵的主要途径,本文阐述了船舶压载水的管理现状和处理方法,以及世界上该领域的最新进展。  相似文献   
126.
In this paper, added resistances acting on a hull of non ballast water ship(NBS) in high waves is discussed. The non ballast water ships were developed at the laboratory of the authors at Osaka Prefecture University, Japan. In the present paper, the performances of three kinds of bow shapes developed for the NBS were theoretically and experimentally investigated to find the best one in high waves. In previous papers, an optimum bow shape for the NBS was developed in calm water and in moderated waves. For a 2 m model for experiments and computations, the wave height is 0.02 m. This means that the wave height is 15% of the draft of the ship in full load conditions. In this paper, added resistances in high waves up to 0.07 m for a 2 m model or 53% of the full load draft are investigated. In such high waves linear wave theories which have been used in the design stage of a ship for a long time may not work well anymore, and experiments are the only effective tool to predict the added resistance in high waves. With the computations for waves, the ship is in a fully captured condition because shorter waves, λ/Lpp0.6, are assumed.  相似文献   
127.
黄勇 《港口科技》2014,(1):17-18,32
为解决滑触线容易积碳的问题,提出一种高架滑触线粉尘在线清洁理念。介绍技术方案及项目实施情况。该装置结构简单,成本低廉,实现了龙门吊在高架滑触线上受电运行时在线实时清除粉尘的功能。  相似文献   
128.
为提高船体水下清洗设备的自动化程度,使清洗设备能在人控制下自动地前进、后退、左转、右转、清刷头的自动提升和下降,文章设计了采用单片机控制液压马达驱动爬行机构运动及红外对射自动调整叶片高度的叶片清洗装置,使清洗设备既洗掉附在船壳上的海生物,又不刮伤船壳表面的油漆。并对整个电路的调试,采用软件进行模拟仿真运行,来提高设计准确率,并在实验中得到验证。  相似文献   
129.
概要介绍国内铁路车辆闸瓦间隙自动调节器配件清洗现状,结合现场大修实际情况,从环保、节能、扩能、安全的角度出发,提出用途广泛的配件超声波清洗系统,介绍其技术方案设计、系统结构组成、技术参数以及使用效果。  相似文献   
130.
该文通过选择新型纤维增强桥面粘结防水层来解决传统柔性防水层设置中难以解决的抗硌破问题,并对新型纤维防水层的施工技术做了较深入的介绍。  相似文献   
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