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821.
对引信炸药装配药过程的危险性作了简要分析,对其危险程度进行了爆炸波事故后果模拟分析. 相似文献
822.
考虑到企业和消费者的低碳策略往往受到政府补贴政策的影响,构建了消费者、消费领域相关企业和政府的三方演化博弈模型,探讨多种因素对各主体策略选择的影响机制.研究表明:企业低碳生产的概率与政府补贴力度、消费者低碳偏好、放弃低碳生产的机会成本和市场损失正相关,与生产方式转变成本负相关;消费者低碳消费的概率与政府补贴力度、低碳偏... 相似文献
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826.
分光光度法与离子色谱法测定空气中氯化氢的对比研究 总被引:1,自引:0,他引:1
通过对硫氰酸汞分光光度法和离子色谱法测定空气中氯化氢含量的对比发现,两种方法对实验室质控样和实际样品的分析测定均能达到要求,且F检验法分析表明实测结果没有显著性差异。然而,硫氰酸汞分光光度法的测试过程操作繁琐,误差较大,稳定时间较长,且硫氰酸汞具有剧毒,危害操作人员的健康,残液也难以处理。离子色谱法分析操作简单,过程安全可靠,能够有效降低样品受污染的可能性并保证分析质量。 相似文献
827.
Thodoris Dantsis Angeliki Loumou Christina Giourga 《Journal of Agricultural and Environmental Ethics》2009,22(3):197-216
Up to now, several scientific works have noted that the organic sector resembles more and more conventional farming’s structures,
what is widely known as the “conventionalization” thesis. This phenomenon constitutes an area of conflict between organic
farming’s original vision and its current reality and raises ethical and social questions concerning the structure of agricultural
systems of production and their interactions with the socio-economic and natural environment. The main issue of this dialogue
is the concept of sustainable agriculture, which for scientists and policymakers is a means to express their vision of a better
agriculture. In this article we focus on agricultural sustainability in the context of capitalist production as conducted
by the two subsystems of agro-industrial system. As we have proposed in this article, the relationship between organic agriculture,
defined by two essential components (prevention and direct marketing), and the agro-industrial complex, defined by two subsystems,
indicates the degree of agricultural sustainability. The investigation of this relationship can be extremely useful as it
may lead those involved in the discussion of sustainability to identify the key aspects of sustainable agriculture. In order
to investigate the interaction of organic farming with the agro-industrial complex, a survey was conducted in Central Macedonia,
Northern Greece, involving local organic farms. The results of our study indicate that a large proportion of organic producers
did not differ substantially from their counterparts in conventional agriculture in so far as their relationship with the
agro-industrial complex is concerned. Finally, this research highlights two scenarios for the evolution of organic farming.
The first is the full absorption of organic farming to the existing economic system and the second one is the development
of organic farming in a radically opposite direction to conventional farming. 相似文献
828.
829.
在相同接种配比(接种污泥占餐厨垃圾的质量分数为30%)条件下,研究了4种不同来源污泥(压滤污泥、厌氧污泥、曝气污泥和河底淤泥)添加或不添加缓冲剂时对餐厨垃圾厌氧发酵产氢效果的影响.结果发现,在不添加缓冲剂时.4种污泥接种餐厨垃圾厌氧发酵平均产氢量依次为厌氧污泥>河底淤泥>压滤污泥>曝气污泥,接种厌氧污泥的餐厨垃圾平均产氢量最高,达10.11mL(以每克挥发性固体(VS)计,下同);而添加缓冲剂时.4种污泥接种餐厨垃圾厌氧发酵平均产氢量依次为厌氧污泥>曝气污泥>压滤污泥>河底淤泥,接种厌氧污泥的餐厨垃圾平均产氢量也最高,为33.72 mL,且体系pH得以缓冲. 相似文献
830.
Energy efficiency and conservation for individual Americans 总被引:1,自引:0,他引:1
D. Pimentel Jennifer Gardner Adam Bonnifield Ximena Garcia Julie Grufferman Claire Horan Julia Schlenker Emily Walling Emily Rochon 《Environment, Development and Sustainability》2009,11(3):523-546
Americans make up only 4% of the world population, yet currently consume 25% of the world’s fossil fuels. The U.S. imports
63% of its oil and it is predicted that by 2020 the U.S. will be importing 95% of its oil resources. Over the past century,
ample and affordable supplies of fossil fuels have powered the growth and prosperity of the economies of the US and other
countries. Within this century, world oil supplies will decline while demand is projected to continue to increase, suggesting
that we will have to transition to different fuels or become much more energy efficient or both. Looking ahead to the near
decades, estimates are that consumers will have to reduce their energy use by at least 50%. This reduction will be necessary
in large part due the decline in the availability of conventional oil and gas, but also because the U.S. population will continue
to grow in number. Although government action is important, individuals too often discount their ability to make significant
contributions to solving such major problems. This investigation identifies how informed and concerned individuals can collectively
conserve fossil energy.
Readers should send their comments on this paper to: BhaskarNath@aol.com within 3 months of publication of this issue.
An erratum to this article can be found at 相似文献