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61.
改善企业安全文化技术手段的应用研究 总被引:1,自引:2,他引:1
安全文化建设在我国企业界受到重视,但是缺乏安全文化建设明确、实用的方法.将安全文化定义为"影响企业安全业绩的核心要素",设计Likert量表、硬件设备和计算机管理系统对安全文化进行定量测量,根据测量结果设计有针对性的培训可以快速改善企业的安全文化.从实际的企业测量可知,通过三次测量、两次抽样培训,企业安全文化可以提高8%左右,说明测量和培训相结合的方法是企业安全文化改善的有效手段. 相似文献
62.
Clifford W. Randall Bruce S. Huloher Paul H. King 《Journal of the American Water Resources Association》1970,6(4):648-660
The activated sludge process can remove significant amounts of phosphorus from sewage, but the removal efficiency is usually significantly reduced by the release of phosphate back to solution during subsequent treatment steps. This research presents a study of soluble phosphate release from activated sludge with emphasis on defining the factors that affect such release and the actual release mechanisms. Laboratory units were used for experimental purposes. The experiments were designed to study the relationship between soluble phosphate release and various environmental factors such as redox potential (ORP), dissolved oxygen (DO), pH, solids concentration, solids destruction, and sulfate salt addition. The effect of substrate utilization on phosphate uptake and the relationship between uptake characteristics and subsequent phosphate release were also studied. The results show that some phosphate storage occurs during aerobic substrate utilization. Following substrate utilization, activated sludge phosphate release is directly related to the amount of biological stress the organisms are subjected to, and the mechanism of release is primarily cell lysis. The phosphate released per unit sludge under anoxic conditions is relatively constant. Under normal environmental conditions, neither ORP or pH change have a significant affect on phosphate release. 相似文献
63.
城市物流形成绿色化发展趋势的主要动因在于汽车运输业的迅速发展及其给城市环境与人们生活质量所造成的巨大影响上.二战以后,汽车运输业的迅速发展和在给社会提供迅速、便捷与准确服务的同时,也给城市的环境造成了严重的负面影响;尤其是由于城市路网和货物运输中心等基础设施既落后且缺乏科学的规划,无形中更加剧了城市物流与城市环境保护之间的矛盾.为实现城市物流的绿色化发展,实践中就有必要合理规划城市物流系统、通过多式联运以尽量降低卡车运输量的比例、积极应用信息技术以推进和实现物流管理的智能化、发展第三方物流实现共同配送. 相似文献
64.
Social movements often amalgamate otherwise diffuse public political interests. In recent years, social media use has allowed both groups and individuals to engage with political issues both online and offline. How do organizations use Twitter to mobilize networked publics? To what extent do groups promote both ‘connective action’ online and traditional activism offline? How do their strategies differ according to whether they seek to promote or combat the status quo? And how do they balance encouraging and reinforcing individualized expression through group messaging? The ways pro-Keystone XL pipeline and anti-Keystone XL groups differed in their Keystone-related action on Twitter from January 2010 until October 2014 are analyzed. Boolean searching and Natural Language processing are used to analyze more than three million tweets. The results demonstrate that the frames within Twitter conversations have significant implications for how communities understand, develop, and mobilize around environmental issues. 相似文献
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A two-dimensional (2D) laboratory model was used to study effects of gravity on areal recovery of a representative dense non-aqueous phase liquid (DNAPL) contaminant by an alcohol pre-flood and co-solvent flood in dipping aquifers. Recent studies have demonstrated that injection of alcohol and co-solvent solutions can be used to reduce in-situ the density of DNAPL globules and displace the contaminant from the source zone. However, contact with aqueous alcohol reduces interfacial tension and causes DNAPL swelling, thus facilitating risk of uncontrolled downward DNAPL migration. The 2D laboratory model was operated with constant background gradient flow and a DNAPL spill was simulated using tetrachloroethene (PCE). The spill was dispersed to a trapped, immobile PCE saturation by a water flood. Areal PCE recovery was studied using a double-triangle well pattern to simulate a remediation scheme consisting of an alcohol pre-flood using aqueous isobutanol ( approximately 10% vol.) followed by a co-solvent flood using a solution of ethylene glycol (65%) and 1-propanol (35%). Experiments were conducted with the 2D model oriented in the horizontal plane and compared to experiments at the 15 degrees and 30 degrees dip-angle orientations. Injection was applied either in the downward or upward direction of flow. Experimental results were compared to theoretical predictions for flood front stability and used to evaluate effects of gravity on areal PCE recovery. Sensitivity experiments were performed to evaluate effects of the alcohol pre-flood on PCE areal recovery. For experiments conducted with the alcohol pre-flood and the 2D model oriented in the horizontal plane, results indicate that 89-93% of source zone PCE was recovered. With injection oriented downward, results indicate that areal PCE recovery was 70-77% for a 15 degrees dip angle and 57-59% for a 30 degrees dip angle. With injection oriented upward, results indicate that areal PCE recovery was 57-60% at the 30 degrees dip angle, which was similar to PCE recovery for injection in the downward flow direction. Lower areal PCE recovery at greater dip angles in either direction of flow was attributed to DNAPL swelling and migration, flood front instabilities and bypassing of the displaced fluid past the extraction wells during the alcohol pre-flood. Additional results demonstrate that the use of an alcohol pre-flood can be beneficial in improving DNAPL recovery in the horizontal orientation, but pre-flooding may reduce areal recovery efficiency in dip-angle orientations. This study also demonstrates the use of theoretical perturbation (fingering) analysis in predicting NAPL recovery efficiency for flooding processes in remediating aquifers with dip angles. 相似文献
67.
采用埋土试验法和微区试验方法,对矿物包裹复合肥料的缓释性进行了研究。结果表明,矿物包裹复合肥料的养分释放明显向后期延伸,矿物包裹复合肥料的肥效期可达120 d以上,比复混合肥料的肥效期至少延长80 d,有利于植物均衡吸收养分,其氮的利用效率比等养分复合肥高出38个百分点;其磷的利用效率比等养分复合肥高出11.5个百分点。 相似文献
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69.
Nicole F. Opalinski Aditi S. Bhaskar Dale T. Manning 《Journal of the American Water Resources Association》2020,56(1):68-81
Weather variability has the potential to influence municipal water use, particularly in dry regions such as the western United States (U.S.). Outdoor water use can account for more than half of annual household water use and may be particularly responsive to weather, but little is known about how the expected magnitude of these responses varies across the U.S. This nationwide study identified the response of municipal water use to monthly weather (i.e., temperature, precipitation, evapotranspiration [ET]) using monthly water deliveries for 229 cities in the contiguous U.S. Using city‐specific multiple regression and region‐specific models with city fixed effects, we investigated what portion of the variability in municipal water use was explained by weather across cities, and also estimated responses to weather across seasons and climate regions. Our findings indicated municipal water use was generally well‐explained by weather, with median adjusted R2 ranging from 63% to 95% across climate regions. Weather was more predictive of water use in dry climates compared to wet, and temperature had more explanatory power than precipitation or ET. In response to a 1°C increase in monthly maximum temperature, municipal water use was shown to increase by 3.2% and 3.9% in dry cities in winter and summer, respectively, with smaller changes in wet cities. Quantifying these responses allows urban water managers to plan for weather‐driven variability in water use. 相似文献
70.