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511.
环境一号卫星环境应用系统工程及其关键技术研究进展   总被引:3,自引:1,他引:2  
简介长达11年的国家重点项目“环境一号卫星环境应用系统工程及其关键技术研究”的核心内容及其重要研究成果,对环境一号卫星系统需求分析、设计理论、研制发射和运行应用全过程进行了完整的研究与实践,为环境一号卫星系统的建设、应用和业务运行奠定了重要基础。  相似文献   
512.
Occupational noise exposure and noise-induced hearing loss (NIHL) has been recognised as a problem among workers in Indian industries. The major industries in India are based on the processing of agricultural products. There are appreciable numbers of pulse processing units spread throughout the country. The purpose of this study was to determine the prevalence of hearing loss among pulse processing workers. As a part of hearing protection intervention, audiometric tests were conducted at the binaural low (250–1,500 Hz), the binaural mid (1,500–4,000 Hz) and the binaural high (3,000–8,000 Hz) frequency averages. The prevalence of hearing loss was determined based on hearing threshold levels (HTLs) with a low fence of 25 dB. Over 50% of pulse processing workers (dana bazaar and dal mill) showed hearing loss in the noise-sensitive higher (binaural mid and high) frequencies. The rate of hearing loss was particularly high among workers in the dal mill. The analyses show a higher risk of prevalence of hearing loss among the dal mill workers compared to the workers associated with the grain preprocessing activities. The study shows alarming signals of NIHL, especially in the dal mill workers. The occupational exposure to noise could be minimised by efficient control measures through engineering controls, administrative controls and the use of personal protective devices. Applications of engineering and/or administrative controls are frequently not feasible in developing countries for technical and financial reasons. A complete hearing conservation programme, including training, audiometry and the use of hearing protection devices, is the most feasible method for the protection of industrial workers from prevailing noise in workplace environments in the developing countries.  相似文献   
513.
Forty-five skulls of European brown bears from the Central Forest Nature Reserve and adjacent regions were examined in detail. The frequencies of oligodonty, dental caries, parodontosis, and traumatized teeth were estimated. A total of 12 variants of the tooth formula were described. The sample under study was distinguished from the populations examined previously by the lowest frequency of oligodonty. Dental caries in one or several teeth, caused by mechanical damage or malocclusion, occurred in 14% of animals. Strong wear marks on the canines caused by feeding on oats frequently resulted in broken canines in bears of the senior age groups.  相似文献   
514.
采用相对电导率差(CPD)法、电导率-pH不等式法对某监测站大气降水的实测电导率和pH值等数据进行质量分析。根据分析结果认为可用CPD法来检验、评估降水中各种离子成分的分析是否完整、准确,用电导率-pH不等式法来检验电导率和pH值的测定值是否存在明显的误差。  相似文献   
515.
取食品生产废水处理中试工程运行中现有的厌氧颗粒污泥进行活性抑制与恢复试验。通过慢性致毒与急性致毒作用的对比,分析酸性条件对颗粒污泥的抑制作用,研究颗粒污泥的耐酸性,并考察污泥活性恢复方法。结果表明:当进水pH=6.5,颗粒污泥活性受到轻微抑制,不影响系统的稳定运行;当pH值下降至4.5时,COD去除率和产甲烷量均趋于零。同时使用调节进水pH值、降低进水有机负荷、提高进水碱度以及调整水力停留时间等4种方法能有效恢复污泥活性,活性达到抑制前的80%左右。  相似文献   
516.
详细介绍山东天圆铜业有限公司为增强企业的竞争力,加快发展循环经济,精心打造高起点、高水平的资源循环利用示范园区和一流的铜加工企业,对企业未来5年打造成为集废旧金属进口、拆解加工、再生铜生产、电解铜生产、高精尖铜材深加工的循环经济产业集团设立目标,为全国城市矿产示范基地的建设提供借鉴。  相似文献   
517.
This study reports the 137Cs data derived from three regional and national scale High Resolution Airborne Resource and Environmental Surveys (HiRES) in northern Britain and Ireland. The detailed spatial resolution, combined with the large areas these surveys collectively cover, gives insight into large-scale deposition patterns and possible subsequent re-distribution of 137Cs on a level that was previously not possible. The largest survey area considered covers the whole of Northern Ireland. All three data sets display some clustering of higher 137Cs activities on high ground together with regional scale NNW-SSE and NW-SE banding features. We interpret these as representing a series of rainfall interceptions of the repeated passage of the Chernobyl plume. Our observations, obtained at 200 m flight line intervals, appear to provide significant detail in relation to existing knowledge of large scale along-wind deposition of 137Cs.  相似文献   
518.
Acceptance by, and cooperation with relevant stakeholders in developing new sustainability initiatives when they are generally perceived as positive, is one of the keys for successful implementation of such new sustainability initiatives later on. It is remarkable, however, that ample literature exists about involving stakeholders in research projects focusing on problems with diverging views (controversy) around facts and values (wicked problems), but there is very little literature addressing whether and how to involve relevant stakeholders in case of initiatives where diverging norms and values do not play a (substantial) role, like in sustainability assessment for a future seaweed industry. This perspectives paper addresses that gap, and explores how to design such sustainability assessment, illustrated by how stakeholder interaction influenced the assessment and its results for a future seaweed industry in Sweden, followed by a discussion whether and how a similar approach may benefit sustainability assessment of other non-wicked sustainability initiatives.  相似文献   
519.
根据CA文摘的要求,以美国《化学文摘》收录部分环境科学文献为例,对收录前后标题、文摘进行探析。论述科技论文文摘的写作与翻译方法,说明科技文摘写作与翻译中存在的不规范和应注意问题,以便科技文摘更具有科学性。  相似文献   
520.
环境温度对直升机的影响及测试数据处理方法研究   总被引:2,自引:2,他引:0  
介绍了高温环境对直升机的影响,分析了影响直升机环境温度的机理,采用曲线拟合和物理相似理论,探讨了环境温度测试数据的处理方法,测试结果可对修订可靠性标准提供主要依据,同时对新机研制环境温度指标有重要的参考价值。  相似文献   
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