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91.
钱家营矿主要通风机性能测定实践研究   总被引:2,自引:1,他引:2  
结合前人的经验 ,根据钱家营矿的实际情况 ,科学制定了主要通风机性能测定方案 ,尤其对西风井的特殊情况进行了大胆实践 ,以周密的安全措施为保障 ,在安全、可靠的前提下 ,采用了独特的测试手段 ,获得了满意的测定结果 ,丰富了主要通风机性能测定的内容和方法  相似文献   
92.
INTRODUCTION: With many thousands of deaths still annually attributable to driving under the influence (DUI), it remains imperative that we continually address the problem of producing and sustaining effective countermeasures, and that we subject these efforts to empirical scrutiny. This article presents relevant findings from state-wide datasets. RESULTS: A formula generating a potentially useful metric for assessing aspects of the DUI prosecutorial chain is presented, focusing on the rate of proactive DUI arrests. While in need of cautious interpretation due to issues of inherent inaccuracies in large databases, small numbers of crashes and/or arrests in multiple jurisdictions, and the lack of replication in other states, the analyses show no relationship between the level of DUI arrest activity and DUI-related crashes. This finding brings into question the efficacy of the many millions of dollars devoted each year to targeted DUI enforcement, as it is currently being implemented. CONCLUSIONS: Results are discussed in terms of developing adequate disincentives to DUI so as to raise general deterrence via dramatic increases in proactive DUI enforcement and then engaging in pervasive and persistent social marketing of such efforts to maximize the perception that arrest and punishment for DUI is always imminent, that penalties will be swift, certain, and severe. It is echoed that accurate data need to be collected at all levels of the DUI arrest and prosecution process in every jurisdiction within a state, so as to facilitate the empirical assessment of countermeasure efficacy in reducing alcohol-related crashes. IMPACT ON INDUSTRY: Given that this work needs to be replicated, the impact on the traffic safety industry is potentially huge. The present data indicate that law enforcement efforts to further abate DUI-related crashes are apparently ineffective, though likely necessary to maintain reductions achieved in the 80s and early 90s. Thus, to attain additional systematic reductions, a dramatic increase in enforcement will be necessary as will a diversification of abatement efforts, including an increase in aggressive social marketing tactics to positively impact our traffic safety culture by making DUI universally unacceptable (for a discussion of this latter issue and on the use of positive reinforcement to change driver behavior, see Dula & Geller, 2007).  相似文献   
93.
A single-screw expander has been designed and manufactured independently. Based on this prototype, testing system has been built and performance experiment has been made. In this article, compressed air was used as working fluid and performance test for the prototype was finished at conditions including different rotational speed and different inlet pressure.

From the experimental data, it is shown that when inlet pressure less than 0.8MPa the output power increases with the increase of rotational speed because of not enough expansion; when inlet pressure more than 0.8MPa, the every biggest output power is appeared in the condition of rotational speed 2600 rpm. The test results also show that the total efficiency is influenced by rotational speed obviously, and the highest total efficiency of this machine is 69.64% in the condition of 3000 rpm and 15 bar.  相似文献   
94.
Infrastructure development is a major driver of biodiversity loss globally. With upward of US$2.5 trillion in annual investments in infrastructure, the financial sector indirectly drives this biodiversity loss. At the same time, biodiversity safeguards (project-level biodiversity impact mitigation requirements) of infrastructure financiers can help limit this damage. The coverage and harmonization of biodiversity safeguards are important factors in their effectiveness and therefore warrant scrutiny. It is equally important to examine the extent to which these safeguards align with best-practice principles for biodiversity impact mitigation outlined in international policies, such as that of the International Union for Conservation of Nature. We assessed the biodiversity safeguards of public development banks and development finance institutions for coverage, harmonization, and alignment with best practice. We used Institute of New Structural Economics and Agence Française de Développement's global database to identify development banks that invest in high-biodiversity-footprint infrastructure and have over US$500 million in assets. Of the 155 banks, 42% (n = 65) had biodiversity safeguards. Of the existing safeguards, 86% (56 of 65) were harmonized with International Finance Corporation (IFC) Performance Standard 6 (PS6). The IFC PS6 (and by extension the 56 safeguard policies harmonized with it) had high alignment with international best practice in biodiversity impact mitigation, whereas the remaining 8 exhibited partial alignment, incorporating few principles that clarify the conditions for effective biodiversity offsetting. Given their dual role in setting benchmarks and leveraging private finance, infrastructure financiers in development finance need to adopt best-practice biodiversity safeguards if the tide of global biodiversity loss is to be stemmed. The IFC PS6, if strengthened, can act as a useful template for other financier safeguards. The high degree of harmonization among safeguards is promising, pointing to a potential for diffusion of practices.  相似文献   
95.
新型丝网填料滴滤器净化含苯废气的实验研究   总被引:2,自引:0,他引:2  
实验研究了新型丝网填料滴滤器净化含苯废气的性能。研究表明该生物滴滤器能够有效的净化含苯废气 ,在入口负荷小于 6 0mg·L-1·h-1时 ,平均净化效率在 90 %以上。当进口负荷提高时 ,消除能力也逐渐提高 ,但净化效率有所下降 ,将进口负荷控制在 30~ 6 0mg·L-1·h-1之间 ,即可以达到高的净化效率 ,又可保持较高的消除能力。苯的净化效率随进气量增加而下降 ,对于净化高浓度苯废气 ,10~ 2 0m/h的气速是比较合适的。不锈钢丝网填料对循环液分布均匀性有较高要求 ,特别在生物膜的形成阶段。当喷淋系统不能保证布液均匀时 ,可采用阶梯环等化工填料作为最初的液体分配层。  相似文献   
96.
郭鼎 《环境与发展》2020,(1):66-66,68
本文从MODIS数据的气溶胶光学厚度反演为理论出发,以河南省近期某一时段下的大气质量为研究对象,论证了反演手段与地面实测数据的契合性和大气遥感监测在大范围时空区域内的优越性和不可替代性;同时结合地面实测数据对河南省AOD空气质量监测做了研究分析,探讨了大气污染专项防治专项的绩效成果并对其影响因素做了进一步分析。在环境问题日益迫切和国民环保意识越发迫切的当下,大气遥感监测势必将会在环保领域发挥更大的作用。  相似文献   
97.
This paper aims at analyzing the feasibility of a waste heat recovery power generation plant based on parametric optimization and performance analysis using different organic Rankine cycle configurations and heat source temperature conditions with working fluid R-12, R-123, R-134a, and R-717. A parametric optimization of turbine inlet temperature(TIT) was performed to obtain the irreversibility rate, system efficiency, availability ratio, turbine work output, system mass flow rate, second-law efficiency, and turbine outlet quality, along the saturated vapor line and also on superheating at an inlet pressure of 2.50 MP in basic as well as regenerative organic Rankine cycle. The calculated results reveal that selection of a basic organic Rankine cycle using R-123 as working fluid gives the maximum system efficiency, turbine work output, second-law efficiency, availability ratio with minimum system irreversibility rate and system mass flow rate up to a TIT of 150°C and appears to be a choice system for generation of power by utilizing the flue gas waste heat of thermal power plants and above 150°C the regenerative superheat organic Rankine cycle configuration using R 123 as working fluid gives the same results.  相似文献   
98.
Community water systems (CWS) face significant competing forces for change from decreasing water resource availability, stricter water quality regulations, decreasing federal subsidies, increasing public scrutiny, decreasing financial health, and increasing infrastructure replacement costs. These competing forces necessitate increasing consolidation responses among financially stressed CWS. Consolidation responses allow financially stressed CWS to increase levels of service by taking advantage of economy of scale benefits, such as eliminating service duplications across administration and operational functions. Consolidation responses also promote improved financial accountability among consolidating CWS, especially when operating as integral subsystems of a larger regional drinking water supply (RDWS) system. The goal of this paper is to propose a conceptual model for robust performance assessment and evaluation (PAE) among consolidating CWS. The objectives of this paper are to conceptualize methods for: (1) consistent performance assessment and (2) uniform summative performance evaluation among consolidating CWS. The expected outcome from implementing robust PAE among consolidating CWS is increased levels of service through transparent benchmarking and improved financial accountability. The proposed robust PAE model provides the basis for constructing decision support system (DSS) tools that estimate efficient solutions for allocating limited financial resources among consolidating CWS. The paper is a significant departure from current CWS PAE approaches in two ways. First, it provides a goal-oriented approach for robust PAE among consolidating CWS. Second, it constructs efficiency-based performance metrics to temporally and spatially monitor the degree of attainment of the RDWS systems' goal.  相似文献   
99.
As population densities have risen and settlements become increasingly crowded, wastewater effluent volumes have, not unexpectedly, also risen. The adverse impacts of effluent from housing estates (HEs) in suburban areas of Thailand, served by local wastewater management (WWM) systems, are of particular concern. Because of this problem, which reflects the poor performance of WWM systems, it has become increasingly important that the pivotal factors that hinder WWM improvements be identified and effective solutions be proposed and implemented. The goal of the research described in this paper was to determine the critical factors influencing WWM performance at HEs in suburban Bangkok, using multiple regression analysis. Three significant factors encompassing financial, social, institutional and general aspects were identified for each type of WWM system (community centralized and onsite). For the community centralized system, the key factors were house price, type of organization managing the HE, and the attitudes of the organization. For onsite systems, the three factors were total number of house units, direct experience with water pollution and percentage of occupied houses. These findings reflect the importance of having a WWM that employs an integrated approach rather than focusing on specific aspects in isolation from other factors. WWM performance could be improved if significant factors indicating high priority concerns were to be identified and properly applied. Addressing the priority concerns could, consequently, contribute to the development of appropriate environmental management measures, plans, and policies related to HE WWM.  相似文献   
100.
生物膜系统的微生物特征和运行管理   总被引:14,自引:1,他引:14  
废水的生物膜处理法,是废水好氧生物处理法中除活性污泥法之外的又一大类方法,亦称之为固着生长法,该文分析了生物膜系统中微生物的种群及其分布特征,详细探讨了生物膜系统运行过程中的一些问题及其防治方法,生物膜法与活性污泥法相比,具有运行管理较简易,方便剩余污泥量少等优点,在处理规模不大的场合颇受欢迎。  相似文献   
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