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621.
622.
阳离子交换树脂生产中废酸的回收利用及树脂质量控制 总被引:3,自引:0,他引:3
采用 酸套洗工艺代替传统的加水稀释洗涤工艺,成功地解决了阳离子交换树脂生产中废酸的回收利用问题,研究了采用新洗涤工艺后树脂变红的机理和防止对策,结果表明,树脂发红帅微生物的参与而引起的。采以完善洗涤 灭菌措施可防止树脂 ,从而确保了稀酸套洗工艺的顺利实施。 相似文献
623.
624.
Yard EE Gilchrist J Haileyesus T Murphy M Collins C McIlvain N Comstock RD 《Journal of Safety Research》2010,41(6):471-474
Introduction
Heat illness is a leading cause of death and disability among U.S. high school athletes.Methods
To examine the incidence and characteristics of heat illness among high school athletes, CDC analyzed data from the National High School Sports-Related Injury Surveillance Study for the period 2005–2009.Results
During 2005–2009, the 100 schools sampled reported a total of 118 heat illnesses among high school athletes resulting in ≥ 1 day of time lost from athletic activity, a rate of 1.6 per 100,000 athlete-exposures, and an average of 29.5 time-loss heat illnesses per school year. The average corresponds to a weighted average annual estimate of 9,237 illnesses nationwide. The highest rate of time-loss heat illness was among football players, 4.5 per 100,000 athlete-exposures, a rate 10 times higher than the average rate (0.4) for the eight other sports. Time-loss heat illnesses occurred most frequently during August (66.3%) and while practicing or playing football (70.7%). No deaths were reported.Conclusions
Consistent with guidelines from the National Athletic Trainers’ Association, to reduce the risk for heat illness, high school athletic programs should implement heat-acclimatization guidelines (e.g., set limits on summer practice duration and intensity). All athletes, coaches, athletic trainers, and parents/guardians should be aware of the risk factors for heat illness, follow recommended strategies, and be prepared to respond quickly to symptoms of illness. Coaches also should continue to stress to their athletes the importance of maintaining proper hydration before, during, and after sports activities.Impact of industry
By implementing preventive recommendations and quickly recognizing and responding to heat illness, coaches, athletic trainers, and the sporting community can prevent future deaths. 相似文献625.
This article analyses growth of an economy where the substitutability between non-renewable and renewable resource inputs changes over time. We allow for exogenous technical change in the elasticity of substitution (EoS) between these two types of resources as well as for biased factor-augmenting technical change. Our main results are: (1) sustained technical change in the EoS is enough to overcome resource constraints; (2) productivity-enhancing technical change is most beneficial when directed to the resource which is currently most important for production; (3) the speed of productivity-enhancing technical change is crucial for its usefulness to overcome resource constraints; (4) sustainability depends critically on the type of technical change. 相似文献
626.
Philip M. Fearnside 《Environmental management》1997,21(4):553-570
627.
Ruud Pleune 《Environmental management》1997,21(5):733-745
2 problem, which brought the issue into the energy debate, as well as the more general definition of the problem in the late
1980s as a greenhouse problem, were very important for determining the strategies of the organizations. It can be concluded
that strategies of Dutch environmental organizations with regard to climate change were strongly dependent on the context. 相似文献
628.
长三角地区石油和化工行业上市公司绿色竞争力的实证研究 总被引:4,自引:0,他引:4
企业绿色竞争力是企业在“绿色化”的前提下,与对手相比的一种竞争优势。石油和化工行业是能源和资源的生产和消耗大户.也是众所周知的重污染行业.对石油和化工企业的绿色竞争力进行实证研究具有重要意义。本文以长三角地区的石油和化工行业上市公司为案例。构建基于DEA法的绿色竞争力评价模型.评估了它们的绿色竞争力。实证结果显示:长三角地区石油和化工企业的绿色竞争力还有待加强.在此基础上提出了石油和化工企业提高绿色竞争力的一些具体措施。 相似文献
629.
We augment the standard cartel formation game from non-cooperative coalition theory, often applied in the context of international environmental agreements, with the possibility that singletons support coalition formation without becoming coalition members themselves. We assume their support takes the form of a monetary transfer to the coalition, in order to induce larger coalitions, higher levels of public good provision and higher payoffs. We show that, under mild conditions on the costs and benefits of contributing to the public good (e.g. abatement of greenhouse gas emissions), there exist equilibria with support. Allowing for support increases payoffs to each of three types of agents: members, supporters and free-riders. 相似文献
630.
This study examines the links between mineral dependency and corruption. Specifically, it develops a cross-section econometric model that estimates the effects of per capita income, fuel exports, non-fuel exports, and average per unit value of mineral exports on corruption. 相似文献