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921.
Wind turbines are a green energy source that Taiwan has been endeavouring to develop in the past five years. Excellent onshore wind farms have already been developed; however, offshore development is inevitable because of Taiwan's limited land area. With regard to energy sustainability, operation and trouble-free maintenance of wind farms are essential. If damage to fan components can be mostly prevented, the operating cost and maintenance time would be considerably decreased; thus, remarkable economic benefits could be achieved. An appropriate coating can help a structure resist the stress of the working environment and improve its durability, resulting in lower maintenance cost and less staff being required to perform on-site repairs. Diatomaceous earth (DE) has been widely used to produce composite porous materials. In this study, epoxy resin and titanium dioxide were mixed with DE to increase the hydrophobicity of the surface of coatings and provide them photocatalytic self-cleaning ability. The ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate was also added to the coatings to prevent the corrosion of coated metallic material. This study employed thermal analysis to investigate the thermal stability of the coatings and the corrosion resistance of coated iron blocks. Finally, a self-made quartz container was connected to a volatile organic compound detector, and sun exposure was simulated using ultraviolet light. The results confirmed that the modified coating retained its functionality under the harsh working environment and can be applied to the surfaces of large machinery used in offshore wind turbine towers.  相似文献   
922.
In order to evaluate the flame-retardant capacity of KHCO3 and ABC on the ignition of PMMA dust layer accumulation on hot surfaces, the ignition time and critical heating temperature of PMMA/KHCO3 and PMMA/ABC dust layer were experimentally investigated. The thermal stability of the mixed dust, the condensed phase products and gas phase products of the mixed dust combustion were analyzed to reveal the flame-retardant mechanism. The ignition time of 30 μm PMMA was obviously longer than that of 5 μm PMMA, and the critical heating temperature was close to that of 5 μm PMMA. KHCO3 and ABC could greatly extend the ignition time of the PMMA dust layer and increase the critical heating temperature of the dust layer. ABC was more effective than KHCO3. The decomposition of KHCO3 and ABC absorbed the heat and inhibits the pyrolysis of PMMA. The HPO3 and P2O5 generated by the decomposition of ABC would cover the surface of PMMA aggregates or particles and act as a physical barrier. The main light combustible gas produced by PMMA pyrolysis were CO and C2H4. The CO2 generated during the decomposition of KHCO3 could dilute the combustible gas in the ambient to inhibit the combustion of PMMA.  相似文献   
923.
本文总结介绍了常见炉型超(超)临界电站锅炉减温器的布置方式和结构形式,并以上海锅炉厂生产的SG-3005/29.3-M7008型超超临界锅炉再热器微量喷水减温器为例,基于水汽温差作用下产生的热疲劳和蒸汽高速冲刷产生的机械振动疲劳原理,探究总结了喷水减温器的失效模式,并提出了设计、制造安装、运行及检验建议.  相似文献   
924.
张可  姚斌 《火灾科学》2021,30(4):242-250
细水雾灭火系统在公路隧道中的应用引发了较多关注,但是针对特大断面公路隧道的研究仍然不足。以2种大断面及4种特大断面公路隧道为研究对象,选取额定流量35 L/min、额定压力10 MPa的高压细水雾喷头,选择4种喷头布置形式,考虑火源功率、位置、遮挡物等影响因素,以隧道顶棚达到耐火极限的临界温度和相邻车辆被引燃的临界热辐射强度为判据,利用FDS模拟软件分析得到适用于隧道的细水雾喷头布置方案。结果表明对于特大断面隧道,细水雾单排顶喷布置不能有效抑制30 MW的大货车火灾,应采用增加顶喷或侧喷喷头的布置形式,从而保护隧道结构安全,防止相邻车辆被引燃。  相似文献   
925.
本文以“要素—领域—任务”国家生态环境规划体系的形成过程为切入点,回顾了新中国成立以来特别是“十一五”之后我国生态环境规划的发展历程。研究表明,在“要素—领域—任务”体系构建完善的关键阶段,即“十一五”到“十二五”,我国的生态环境规划体系在“污染减排”的基础上,明确提出“质量改善”“风险防范”和“公共服务”三大领域,战略领域的划分逐步明确,环境规划要素逐渐充实,落实任务更加精细。而在“要素—领域—任务”体系的充实提高过程中,即“十二五”到“十三五”,进一步提出“绿色发展”“生态修复”“制度创新”三大领域。要素方面,通过推进“三大污染防治行动计划”,使气、水、土三要素治理纲举目张。任务的重心则向生态环境综合治理、区域统筹协调发展转变。为更好地发挥“要素—领域—任务”体系优势,支撑我国现代环境治理体系的构建,本文提出,“十四五”规划应在要素层面全面覆盖且重点突出,领域层面系统整合并统筹协调,任务层面具体落实且创新机制,助力建成适应美丽中国建设要求的生态环境管理体系新格局。  相似文献   
926.
When wildlife habitat overlaps with industrial development animals may be harmed. Because wildlife and people select resources to maximize biological fitness and economic return, respectively, we estimated risk, the probability of eagles encountering and being affected by turbines, by overlaying models of resource selection for each entity. This conceptual framework can be applied across multiple spatial scales to understand and mitigate impacts of industry on wildlife. We estimated risk to Golden Eagles (Aquila chrysaetos) from wind energy development in 3 topographically distinct regions of the central Appalachian Mountains of Pennsylvania (United States) based on models of resource selection of wind facilities (n = 43) and of northbound migrating eagles (n = 30). Risk to eagles from wind energy was greatest in the Ridge and Valley region; all 24 eagles that passed through that region used the highest risk landscapes at least once during low altitude flight. In contrast, only half of the birds that entered the Allegheny Plateau region used highest risk landscapes and none did in the Allegheny Mountains. Likewise, in the Allegheny Mountains, the majority of wind turbines (56%) were situated in poor eagle habitat; thus, risk to eagles is lower there than in the Ridge and Valley, where only 1% of turbines are in poor eagle habitat. Risk within individual facilities was extremely variable; on average, facilities had 11% (SD 23; range = 0–100%) of turbines in highest risk landscapes and 26% (SD 30; range = 0–85%) of turbines in the lowest risk landscapes. Our results provide a mechanism for relocating high‐risk turbines, and they show the feasibility of this novel and highly adaptable framework for managing risk of harm to wildlife from industrial development. Evaluación del Riesgo para las Aves por el Desarrollo de Energía Eólica Industrial Mediante Modelos de Selección de Recursos Pareados.  相似文献   
927.
The road accident of a tanker transporting liquefied natural gas (LNG) originated a fire and, finally, the BLEVE of the tank. This accident has been analyzed, both from the point of view of the emergency management and the explosion and fireball effects. The accidental sequence is described: fire, LNG release, further safety valves release, flames impingement on vessel unprotected wall, vessel failure mode, explosion and fireball. According to the effects and consequences observed, the thermal radiation and overpressure are estimated; a mathematical model is applied to calculate the probable mass contained in the vessel at the moment of the explosion. The peak overpressure predicted from two models is compared with the values inferred from the accident observed data. The emergency management is commented.  相似文献   
928.
929.
The Oliveri-Tindari Lagoon, located in North-Eastern Sicily (Italy) and composed of six lakes, is subject to continuous environmental changes. An integrated study focusing on sediment features and levels of contamination was carried out for three of the six lakes, which are of ancient origin: Verde, Mergolo della Tonnara and Marinello. A high primary production (26.89 μg l?1) was detected at Lake Verde; texture classification showed a typical grain size in the sediments of all lakes; the study of macronutrients highlighted 17.08 of total carbon in sediments from Lake Mergolo della Tonnara; toxic elements were detected at higher concentrations in the sediments of Lake Marinello in comparison to the others, while arsenic was found in high concentrations in all the samples tested, especially in Lake Verde, with a mean value of 17.25 mg kg?1 dry weight (d.w.). All the organic contaminants, except 4, 4′-dichlorodiphenyldichloroethylene, were below the detection limits in the sediments. Minimal microbiological contamination was found in both water and sediment samples. In the latter, we isolated several bacterial strains thriving in the presence of arsenic, which play a role in the biogeochemical cycle of arsenic. These preliminary results, obtained for the first time using a multidisciplinary approach, provide general information about the Oliveri-Tindari Lagoon area.  相似文献   
930.
Soil organic carbon (SOC) and soil total nitrogen (STN) concentrations and stocks are essential for improving soil quality and increasing C-reservoir. The study aimed at quantifying the dynamics of soil properties under different land use in Imo watershed where there is no knowledge about the effects of land use on SOC and STN pool. Six land use: arable land (AL), forest land (FL), grassland (GL), shrubland hills (SL), urban built-up green (UL), and freshwater swamp-mangrove wetland (WL) were classified using ArcGIS 10.1 and FAO land use classification system. Soil samples were collected and analyzed from each land use under different soil depths and slope positions with three replications. Topsoil layer (0–30?cm) contributed to more than 90% of the total soil nutrients. Land use significantly affected SOC content, STN content, and bulk density. SOC and STN concentrations were in the order of FL?>?WL?>?GL?>?SL?>?UL?>?AL which revealed the potentials of FL and WL for SOC and STN sequestration. The study provides land users with the information to improve soil quality, conserve C and N stocks for ecological sustainability and climate change mitigation.  相似文献   
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