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231.
In order to investigate the possible coupling between sexual maturation and the light organ system (LOS) development in leiognathid fish, we determined the seasonal changes in the gonad maturation and the light organ enlargement in Photoplagios rivulatus, one of the leiognathid species possessing highly sexually dimorphic LOS. The fish specimens collected from March 2001 to August 2002 were assessed for standard length (SL), body weight (BW), sex, gonad weight (GW) and the light organ weight (LW). Gonadosomatic index (GSI = 102GW/BW) and percent weight of the light organ to body weight (PLW = 102 LW/BW) were used to demonstrate the extent of development of gonad and the LOS, respectively. Mean GSIs in both male and female increased in June through August. The mean PLW in males showed a similar trend to that of the GSI, while PLW in females showed no clear seasonal trends. A significant positive correlation was found between the GSI and the PLW in males but not in females. The onset of sexual maturity in males (55 mm SL) coincided with that of the light organ enlargement. These results strongly support the functional coupling between reproduction and bioluminescence in this species of leiognathid. From an evolutionary perspective, sexual dimorphism in the LOS is likely to have evolved through sexual selection for reproductive success in leiognathid fishes.  相似文献   
232.
日本企业安全培训现状及对中国的启示   总被引:2,自引:2,他引:0  
依据中日合作项目<加强中国国家安全生产科学技术能力计划>成果,系统介绍了日本企业安全培训相关法规要求、班组长培训讲师培养、安全培训指导方案编制等.同时,分析了中国安全培训现状,提出了开展企业内安全培训讲师培养,加强中国企业安全培训能力的建议,并对堵训目的、培训对象、培训讲师主要工作、培训主要内容等要点进行了阐述.本文对完善和提高中国企业安全培训具有重要的指导和参考意义.  相似文献   
233.
This is the second of a two-part article that reviews electrostatic precipitation theory, presents size estimating methods, and gives costing procedures for a variety of electrostatic precipitator (ESP) types and sizes. Part I of the article, which appeared in the April 1988 issue of JAPCA, discussed theory and sizing; this part presents costing. Information is given for estimating total capital investment including separate costs for the bare ESP (five types) and auxiliaries. Factors are given for installation and for indirect costs. Direct and indirect annual costs are discussed. An example problem is given.  相似文献   
234.
我国安全生产法制对策研究   总被引:3,自引:3,他引:0  
分析了国内外安全生产法制现状,总结提出了我国存在的职业安全与健康分离、没有系统和规划、适用和衔接性差等特点和问题。阐述了安全生产法规体系建设的指导思想、基本原则以及基本框架,并提出了定期制定安全生产法规规划、梳理与评估法规体系实施效果、制定统一的劳动安全与健康法、编制安全生产计划、健全职业健康配套规定、保险与安全生产互动、以明确综合监管和专项监管以及安全生产规划、完善隐患治理、安全使用机械、健全企业自主管理体制等为重点对《安全生产法》进行修订的对策。  相似文献   
235.
To elucidate the macro-structure of the PM2.5 emissions generated by Japan's economic activities, this paper presents an emission inventory of primary particles of PM2.5 with high sectoral resolution based on the Japanese Input–Output Tables, comprising some 400 sectors. These primary PM2.5 emissions were estimated by multiplying the estimated energy consumption associated with each fuel type by a PM10 emission factor incorporating the technological level of dust collection in each sector and the mass ratio of PM2.5 to PM10. Non-energy emissions from agricultural open burning were also determined. Total PM2.5 emissions in 2000 were 252 kt, 49% of which were due to mobile emission sources. Changes in total PM2.5 emissions between 1990 and 2000 were also calculated. This showed that a substantial increase in energy sector emissions due to rising coal consumption was offset by a sharp decline in emissions from road vehicles and shipping vessels, resulting in an overall decrease in total emissions. In addition, the emissions induced by economic demand in each sector were quantified by means of input–output analysis, which revealed that demand for construction, foods and communications and services constituted the principal causes of real domestic emissions. An assessment of sectoral contributions to PM2.5 emissions that takes into account the effects of human exposure, expressed as external costs, suggests that the contribution of transportation is greater than indicated on the grounds of direct emissions alone.  相似文献   
236.
Ecological risk assessment of TBT in Ise Bay   总被引:1,自引:0,他引:1  
An ecological risk assessment of tributyltin (TBT) in Ise Bay was conducted using the margin of exposure (MOE) method. The assessment endpoint was defined to protect the survival, growth and reproduction of marine organisms. Sources of TBT in this study were assumed to be commercial vessels in harbors and navigation routes. Concentrations of TBT in Ise Bay were estimated using a three-dimensional hydrodynamic model, an ecosystem model and a chemical fate model. Estimated MOEs for marine organisms for 1990 and 2008 were approximately 0.1-2.0 and over 100 respectively, indicating a declining temporal trend in the probability of adverse effects. The chemical fate model predicts a much longer persistence of TBT in sediments than in the water column. Therefore, it is necessary to monitor the harmful effects of TBT on benthic organisms.  相似文献   
237.
Modeling changes in paddy rice sown areas in Asia   总被引:1,自引:0,他引:1  
Paddy rice fields in Asia account for over 90% of global total rice cultivation area, and the major rice-producing countries of Asia account for over one-half of the world’s population. Monitoring and understanding the dynamic changes in paddy rice agriculture in Asia are very important for agricultural sustainability, food and water security, and greenhouse gas emissions. This paper presents a crop choice decision model that dynamically simulates future changes in sown areas of paddy rice in Asia. This model was developed under the framework of Action-in-Context (AiC) with the aim of understanding land users’ decisions on crop choices among a set of available alternatives using a crop utility function. Empirical validation for the model conducted after model construction indicated the reliability of the model for addressing the complexity of current agricultural land-use change and its capacity for investigating long-term scenarios in the future. Finally, the model was applied for future scenario analysis over a time frame of 30 years with 5-year increments, beginning from the year 2005. The simulation results provided insights into rates and trajectories of changes in Asian rice areas over the test period, with the resulting implications for future agricultural sustainability in Asia. These outcomes can improve understanding of projected land-use changes and explain their causes, locations and consequences, as well as providing support for land-use planning and policy making.  相似文献   
238.
Large-scale storage of carbon dioxide in saline aquifers may cause considerable pressure perturbation and brine migration in deep rock formations, which may have a significant influence on the regional groundwater system. With the help of parallel computing techniques, we conducted a comprehensive, large-scale numerical simulation of CO2 geologic storage that predicts not only CO2 migration, but also its impact on regional groundwater flow. As a case study, a hypothetical industrial-scale CO2 injection in Tokyo Bay, which is surrounded by the most heavily industrialized area in Japan, was considered, and the impact of CO2 injection on near-surface aquifers was investigated, assuming relatively high seal-layer permeability (higher than 10 microdarcy). A regional hydrogeological model with an area of about 60 km × 70 km around Tokyo Bay was discretized into about 10 million gridblocks. To solve the high-resolution model efficiently, we used a parallelized multiphase flow simulator TOUGH2-MP/ECO2N on a world-class high performance supercomputer in Japan, the Earth Simulator. In this simulation, CO2 was injected into a storage aquifer at about 1 km depth under Tokyo Bay from 10 wells, at a total rate of 10 million tons/year for 100 years. Through the model, we can examine regional groundwater pressure buildup and groundwater migration to the land surface. The results suggest that even if containment of CO2 plume is ensured, pressure buildup on the order of a few bars can occur in the shallow confined aquifers over extensive regions, including urban inlands.  相似文献   
239.
To develop a new method for the chemical recycling of plastics, we examined the formation of recycled polymers from the recovered monomeric materials of solubilized waste fiber-reinforced plastics (FRP) under supercritical alcoholic conditions. Treatment of waste FRP with supercritical MeOH resulted in the formation of monomeric organic compounds that mainly contained dimethyl phthalate (DMP) and propylene glycol. The presence of these materials was confirmed by gas chromatography and nuclear magnetic resonance analyses and they were mixed with new DMP and glycols in various ratios to form unsaturated polyesters. The polymerization progressed successfully for all mixing ratios of the recovered and new DMP. Hardness tests on these recycled polymers indicated that the polymer made from a 1:1 mixture of recovered and new dimethyl phthalate had almost the same level of hardness as the polymers made from new materials. We also examined the formation of recycled FRP by using glass fibers and monomeric materials recovered through the present depolymerization method. Chemical Feedstock Recycling & Other Innovative Recycling Techniques 6  相似文献   
240.
Gong Z  Yang F  Liu S  Bao H  Hu S  Furukawa K 《Chemosphere》2007,69(5):776-784
A laboratory-scale membrane-aerated biofilm bioreactor (MABR) equipped with non-woven fabrics support around the gas-permeable carbon tube was developed for single-stage autotrophic nitrogen removal based on partial nitrification and anaerobic ammonium oxidization. This reactor allowed air to be supplied through the microporous carbon tube wall to the biofilm that was supported by non-woven fabrics. The partial nitrification and consumption of dissolved oxygen occurred in the inner layer and Anammox in the anoxic outer layer of the non-woven fabrics, thus realizing autotrophic nitrogen removal in a single reactor. After 116d of operation, the maximal nitrogen removal of 0.77kgNm(-3)d(-1) at a volumetric ammonium loading rate of 0.87kgNm(-3)d(-1) was achieved. The spatial profiles of the ammonia-oxidizing bacteria and Anammox bacteria were evaluated by fluorescence in situ hybridization. This study demonstrated that MABR was a very suitable experimental set-up for the operation of the single-stage autotrophic nitrogen removal process.  相似文献   
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