罗非鱼中甲基睾酮超高压液相色谱测定方法

超高压液相色谱法测定罗非鱼中的甲基睾酮残留。样品经乙醚超声波提取、石油醚纯化，以BEH C18柱、70 %甲醇溶液洗脱分离，PDA检测器，外标法定量。结果表明，回收率不低于80 %，相对标准偏差不高于6.50 %，定量限为8 mg/kg。该法准确可行、前处理简便、适用于批量样品的检测。     

齿轮泵圆形卸荷槽下的困油压力分析

计算齿轮泵圆形卸荷槽下的卸荷面积和对应的困油压力。以困油的膨胀过程为例,首先通过啮合点位置和圆形槽圆形轮廓与从动轮齿廓和主动轮槽廓的交点位置计算,给出卸荷面积的精确计算方法,其结果由虚拟的测量数据验证;其次由流体体积弹性模量定义所构建的困油模型,对圆形、矩形两卸荷槽下的困油压力分别进行仿真运算,结果则被相关文献提供的试验结果所验证。结果表明:卸荷面积的计算结果与虚拟测量结果非常吻合;困油压力峰值的仿真结果与现有试验结果也非常吻合。当泵采用小侧隙大卸荷槽间距时,应多采用矩形槽,以提供更大的卸荷面积;当泵采用大侧隙小卸荷槽间距时,应当多采用圆形槽,以降低加工维修成本。     

基于熵权系数评价模型的烟田灌排工程综合效益分析

针对烟区土壤连作障碍、病虫害、灌溉设施落后等问题,设计不同的灌排处理,对不同处理烤烟增产效益、提质效益和灌排工程的经济效益进行分析,同时引入熵权系数评价模型,对不同灌排工程方案进行优选和评价。结果表明:不同灌排工程均具备较好的增产效益和提质效益(W1除外),微喷灌工程的增产和提质效益总体要优于低压管道;W2~W5灌排工程均具备了经济可行性,不同工程方案以W5经济效益最优,EIRR、ENPV和EBCR值分别达到27.80%、2 894.35%和2.04;本试验中综合效益最佳的灌排方案为微喷灌灌溉结合暗管排水,其中暗管间距为6m,埋深0.8m。     

基于CAN总线的液压支架压力传感器自动化系统的设计

以煤矿液压支架压力传感器为研究对象,结合设计规范,设计了一种基于CAN总线的智能压力传感器。分析了CAN节点的分类和功能特点,介绍了系统的配置方式,探讨了CAN节点的硬件和软件设计方案。     

低矮房屋屋面实测峰值风压分析

通过作者研制的一套可移动实验房及测试系统对近地登陆台风风速和房屋表面风压进行同步观测，研究登陆台风近地边界层风场和低矮房屋风效应.基于0801“浣熊”台风实测数据，分析了实验房屋面角部区域局部峰值负压分布特征和相关性，探讨了角部区域峰值压力时间和空间的平均拆减效应.结果发现,峰值负压系数大于现行规范规定值；并运用广义极值概率模型极值III型对角部测点峰值负压进行极值分析，角部测点峰值负压系数与其实测峰值负压相比要大26.4％.相对良态天气条件，在台风天气作用下低矮房屋屋面角部区域局部易形成较高吸力远大于现行规范推荐值.     

Using a well‐being approach to develop a framework for an integrated socio‐economic evaluation of professional fishing

The principles of Ecologically Sustainable Development and Ecosystem Based Fisheries Management require that fisheries be managed for social as well as environmental and economic objectives. Comprehensive assessments of the success of fisheries in achieving all three objectives are, however, rare. There are three main barriers to achieving integrated assessments of fisheries. Firstly, disciplinary divides can be considered “too hard” to bridge with inherent conflicts between the predominately empirical and deductive traditions of economics and biophysical sciences and the inductive and interpretative approach of much of the social sciences. Secondly, understanding of the social pillar of sustainability is less well developed. And finally, in‐depth analysis of the social aspects of sustainability often involves qualitative analysis and there are practical difficulties in integrating this with largely quantitative economic and ecological assessments. This article explores the social well‐being approach as a framework for an integrated evaluation of the social and economic benefits that communities in New South Wales, Australia, receive from professional fish harvesting. Using a review of existing literature and qualitative interviews with more than 160 people associated with the fishing industry the project was able to identify seven key domains of community well‐being to which the industry contributes. Identification of these domains provided a framework through which industry contributions could be further explored, through quantitative surveys and economic analysis. This framework enabled successful integration of social and economic, and both qualitative and quantitative information in a manner that enabled a comprehensive assessment of the value of the fishery.     

灌溉用压力调节器性能试验与受力分析

为了研究灌溉系统压力调节器的工作特性与结构参数的关系,对7种内置弹簧式规格的低流量压力调节器进行了调压特性试验,对压力调节器的弹簧参数与出口预置压力的关系以及内部运动部件的受力情况进行了分析.结果表明,压力调节器的出口预置压力越低,调压性能越优良,测得的临界工作压力与出口预置压力之差随着出口预置压力的增大而增大,并非常数0.034 MPa;随着出口预置压力的上升,内置弹簧丝直径越粗,弹簧自由长度越短,其弹簧刚度系数越大;压力调节器调节组件所受的初始弹簧力和最大弹簧力与出口预置压力存在近似的线性关系,而且在向压力调节器进口端运动的过程中,调节组件所受的弹簧力占其出口所受水压作用力从57.9%逐渐增大至66.5%,而密封圈摩擦力和橡胶膜片变形力之和占出口所受水压作用力则从39.9%下降至31.3%.     

Spatio‐temporal management of fisheries to reduce by‐catch and increase fishing selectivity

Time/area closures have been widely used in fisheries management to prevent overfishing and the destruction of marine biodiversity. To a lesser degree, such spatio‐temporal management measures have been used to reduce by‐catch of finfish or protected species. However, as ecosystem‐based management approaches are employed and more fisheries are managed through multispecies, multiobjective models, the management of by‐catch will likely become increasingly important. The elimination of by‐catch has become a primary goal of the fishing policies of many countries. It is particularly relevant in the United States, as the deadline for setting annual catch limits (ACLs) in all fisheries passes in 2011. This will result in a dramatic expansion of the number of catch and by‐catch quotas. Such catch measures may result in the early closure of otherwise sustainable fisheries when by‐catch quotas are exceeded. To prevent such closures and the consequent economic hardship to fishers and the economy, it is imperative that managers be given the tools necessary to reduce by‐catch and improve fishing selectivity. Targeted spatio‐temporal fishery closures are one solution open to managers. Here, we examine how the spatio‐temporal and oceanographic characteristics of by‐catch may be used by managers to design fishery closures, and place these methods within a decision tree to assist managers to identify appropriate management measures. We argue that the current movement towards marine spatial planning (MSP) presents an important impetus to examine how we manage fisheries spatially, and we offer a first step towards the objective participation of fisheries in the MSP process.     

沿海渔港淤积与污染问题的调查研究

以沿海渔港建设标准编制工作为契机,对我国沿海几个省市的代表性渔港开展调研活动,通过问卷调研和实地考察,初步了解了目前我国沿海渔港的建设现状及存在的问题,其中,重点讨论造成港池淤积与环境污染现象的原因,并给出适当的解决办法.为解决由于建筑物设计、固液体垃圾肆意排放、处理设备不足、作业人员素质低下等原因造成的港池淤积和环境...