三峡电厂设备备件国产亿的 探索与实践

目前三峡电厂机组已进入正常的运行,维护期,其备品备件的管理是其安全生产的一个重要环节。为了克服进口备件的不利因素,保证备件及时供应,满足发电需求,确保三峡综合效益的正常发挥,必须尽快有选择性地做好相关设备国产化的工作。本文着重阐述了三峡电厂在部分进口设备备件国产化试验中的探索过程和经验,以期为中国巨型水电机组备品备件的供应和管理提供经验。     

动静组合分离器与静态分离器比较以及在印度工程上的应用

介绍了中速磨煤机静态分离器及动静组合分离器工作原理,比较了动静组合分离器与静态分离器的区别,并研究了两种分离器在印度安巴拉项目磨煤机上的应用。根据现场运行结果,动态分离器在寿命和运行效果上都优于静态分离器。     

光伏电站设计智能优化

由于目前光伏电站设计目前没有相应的标准,因此以个人经验为指导的情况,无法保证电站建设的成本最优,鉴于此问题,本文提出了一种光伏电站优化设计方法,基于模拟退火算法,通过对光伏区域中的组件进行最优分组来实现两级电缆成本的最优。并通过实际项目对该算法进行检验,达到比较理想效果。     

植物设计在居住区景观适宜空间中的营造——以青岛李沧万科生态城A3地块为例

居住区是人们重要的生活及活动场所,其景观设计建设的舒适程度直接关系着人们的生活质量。植物设计作为居住区景观设计中非常重要的一方面,对于居住区的空间形成至关重要。我们针对具体项目,简要分析了植物在居住区景观适宜空间营造中的应用,同时做出评价。     

Biochemical factors responsible for susceptibility or resistance of various plants against the scarlet mite,brevipalpus phoenicis: i. amino acids analysis

Free amino acids show considerable variations among various species of plants that exhibit different degrees of susceptibility or resistance to various pests infestation. Some of the free amino acids, directly or indirectly, contribute to defense mechanism of the plants. Recently, 31 plant species were screened for susceptibility or resistance against the attack of the scarlet mite, Brevipalpus phoenicis (Geij.). Thin layer chromatography showed that all resistant species contain tryptophan, tyrosine and hydroxyproline, while all susceptible hosts had amino acids like α‐aminocaprylic acid and dihydroxyphenylalanine. The plants species lacking dihydroxyphenylalanine could not support the development of the scarlet mite.     

Metal concentration in cocoa seeds shell ash,liquid effluent,soil sediments and associated plants in a cocoa processing industry in Nigeria

Levels of iron, zinc, manganese, copper, tin, aluminium, magnesium, sodium, potassium, lead, arsenic, chromium, cadmium, titanium and calcium were determined in cocoa seeds shell ash, liquid effluent, soil sediments and associated plants (kokoyam and cassava parts) using an atomic absorption spectrophotometer from a cocoa processing industry located at Akure along the Akure–Owo express road, Ondo State, Nigeria. The soil sediments metals were more highly concentrated than the corresponding values in the liquid effluent; both samples showed evidence of metal bioaccumulation. The toxic trace metals determined were mostly above the permissible safe levels. Plants should not be planted along the effluent channel to avoid plant bioaccumulation of toxic metals.     

A Moisture Transfer Model for Isothermal Drying of Plant Cellular Materials Based on the Pore Network Approach

Plant materials with cellular structure, like fruits and vegetables, are often viewed as porous media in terms of model building of the drying process, on the basis of a hypothesis that all of the moisture of a plant tissue is trapped in a continuous and connected pore network system. However, most of the moisture in the plant tissue is contained naturally in enclosed cells. In the course of drying, the trapped moisture has to cross the cell membranes and then migrates in the extracellular space. Based on this concept, a pore network model for isothermal drying of plant materials was developed in which two stages of moisture movement—transmembrane transfer and extracellular transfer in the pore network—were considered. Finally, the isothermal convective air-drying processes of a potato slice were simulated. The calculated results were validated by the experiments conducted under the simulation conditions.     

小湾水电站进水口高边坡监测及信息反馈研究

针对小湾水电站垂直开挖高度81m进水口直立边坡大量监测资料,结合变形、地质、开挖和加固处理影响因素,分析了边坡变形特征;评价了以f3为控制性底滑面不稳定楔形体的加固效果以及对抑制卸荷松弛变形作用;通过监测信息反馈,设计有针对性地及时进行边坡动态支护优化,使预应力锚索达到了较佳工作状态,充分发挥了锚固作用。     

贺州市水电站工程质量监督工作的现状及对策

分析了近年来贺州市小水电建设中存在的管理失控、不完全履行建设质量监督程序及具体工程建设中出现的一些质量事故及原因,针对这些问题,提出了健全质量监督机构、提高质量监督队伍素质、规范建设审批手续等建议.     

Plant products as fumigants for stored-product insect control

Research studies on plant essential oils and their constituents as fumigants, i.e., compounds acting on target insects in the vapour or gaseous phase, against stored-product insects have been reviewed. Fumigant toxicity tests conducted with essential oils of plants (mainly belonging to Apiaceae, Lamiaceae, Lauraceae and Myrtaceae) and their components (cyanohydrins, monoterpenoids, sulphur compounds, thiocyanates and others) have largely focused on beetle pests such as Tribolium castaneum, Rhyzopertha dominica, Sitophilus oryzae and Sitophilus zeamais but little or no attention has been paid towards moths such as Corcyra cephalonica and Sitotroga cerealella. Adults were generally susceptible, whereas, eggs were either tolerant or highly susceptible depending on insect species and the type of essential oil or component. The essential oils proved effective in mixture with CO₂ or ethyl formate. Mode of action studies on monoterpenoids indicate inhibition of acetylcholinesterase enzyme activity as the major site of action. Although, in laboratory tests with adult insects, some of the plant compounds have shown insect toxicity comparable to methyl bromide or chloropicrin, their physical properties such as high molecular weight as well as high boiling point and very low vapour pressure are barriers for application in large-scale fumigations. Plant products, therefore, have the potential for small-scale treatments, space fumigations and as adjuvants for conventional fumigants. The constraints including lack of data for single or multiple components of essential oils on sorption, tainting and residues in food commodities, and registration protocols have been highlighted. The use of egg and pupal stages or preferably mixed-age cultures of target insects in screening tests with any new plant essential oil/compound has also been stressed.