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941.
当前,距离2020年实现农业农村污染治理攻坚战目标的时间不到两年,我国农村环境整治工作仍面临着资金投入空缺较大、村民内生动力不足等突出问题。本文在明确激发农民内生动力的意义和必要性后,全面分析了当前农村环境整治形势,深刻阐述了村民参与环境整治的制约因素,并分别从事权划分、推进方式、奖惩机制和思想意识四方面,提出了激发村民内生动力助力农村污染治理攻坚战的对策建议。 相似文献
942.
943.
干旱区荒漠植被的特点及恢复问题的研究--以塔里木河流域胡杨林生态系统为例 总被引:2,自引:0,他引:2
干旱区除存在唯一的真正森林-胡杨(Populuseuphratica)林外,植被普遍极其稀疏,以降水稀少,蒸发显著为特点的干旱区,荒漠植被的存在对于生态环境的保护和良性发展起到极大的作用,干旱区的荒漠植被表现出特有的生理特征,本文研究塔里木河流域胡杨林的特征及对生态环境的适应规律,进一步提出了扩展荒漠植被的可能性及其措施。 相似文献
944.
Bjerre B 《Traffic injury prevention》2003,4(2):98-104
The Swedish alcohol ignition interlock program for driving while intoxicated (DWI) offenders, both first-time as well as multiple offenders, was launched as a pilot project in 1999. It is a volunteer program and differs in some respects from other programs: It covers a period of 2 years, it includes very strict medical regulations entailing regular checkups by a physician, it does not require a prior period of hard suspension, and it focuses strongly on changes in alcohol habits. Records from the 5 years prior to the offence showed that DWI offenders are generally in a high-risk category long before their offense, with a four to five times higher accident rate (road accidents reported by the police) and a three to four times higher rate of hospitalization due to a road accident. Only 12% of the eligible DWI offenders took part in the program and, of these, 60% could be diagnosed as alcohol dependent or alcohol abusers. During the program, alcohol consumption is monitored through self-esteem questionnaires (AUDIT) and five different biological markers. Our data show a noticeable reduction in alcohol consumption among the interlock users. This, combined with the high rate of compliance with the regulations, probably accounts for the fact that there was no case of recidivism during the program. Preliminary findings also suggest a reduction in the annual accident rate for interlock users while in the program. It still is too early to draw any conclusions concerning the rate of recidivism after completion of the program due to an insufficient amount of data for analysis. Nevertheless, the preliminary results are so promising that the program will now be expanded to cover all of Sweden as well as to include all driver's license categories. 相似文献
945.
/ This study was conducted to examine norm prevalence, norm agreement, and norm stability in an international setting. Data were collected at two campgrounds in Chiri-Mountain National Park, Korea, in 1993 and 1994. Results showed that a high proportion of users could specify norms for various types of campground impacts. Users who rated high importance on impacts tended to show a higher level of norm prevalence. Generally there were differences in social norms and norm agreement across locations. Among those impacts that showed differences, social norms in a less developed area were more restrictive and norm agreement was higher. The results of this study are consistent with normative studies conducted in North America, suggesting that a normative approach can be applied in a variety of settings. Social norms for selected impact indicators were also stable over a one-year time period. Implications are discussed.KEY WORDS: Norms; Norm prevalence; Norm agreement; Norm stability 相似文献
946.
Shunli Zhang Eric Forssberg Bo Arvidson William Moss 《Resources, Conservation and Recycling》1998,23(4):225-241
The amount of electronic scrap which contains a substantial portion of non-ferrous metals, primarily copper and aluminum, has been growing. The present study is directed toward aluminum recovery by a newly developed eddy current separator. The investigation on shredded personal computer and printed circuit board scrap demonstrates that the High-Force® eddy-current separator will be applicable for this purpose. It has been shown that, by a single pass of the materials on the High-Force® eddy-current separator, an aluminum concentrate out of personal computer scrap can be obtained with a purity of 85%, while maintaining a recovery in excess of 90%, with the feed rate being up to 0.3 kg/min. 相似文献
947.
基于湖北省2018年4-10月臭氧、温度和相对湿度逐小时监测数据以及50 m风场逐小时再分析数据,采用经验正交函数(EOF)和奇异值分解(SVD)方法,分析了2018年湖北省臭氧特征及其高值与气象要素关系。结果表明:湖北省臭氧日最大8 h浓度距平呈现以武汉为正值中心、自鄂东向鄂西递减的主要空间分布型;15:00臭氧与温度呈现较好的正相关关系,以随州、襄阳及其周边最为明显;与14:00相对湿度呈现很好的负相关关系,以孝感、随州、荆门及其周边最为明显;襄阳西部和十堰北部地区15:00 50 m风场的纬向分量对本地臭氧高值有一定影响,武汉北部、黄冈北部以及孝感东部等地15:00 50 m风场的经向分量对本地臭氧高值影响较大。 相似文献
948.
949.
滇池草海污染治理工程是一个复杂的系统,做好规划是保证工程治理效果和有效使用投资的前提。本文将综合治理目标和各决策变量建立函数关系,并将其分析归纳为线性规划问题,根据线性规划的求解原则求出了目标规划的优化方案。 相似文献
950.
新型厌氧反应器处理生活污水的研究进展 总被引:4,自引:0,他引:4
新型高速厌氧反应器的发生使生活污水的厌氧处理成功可能,介绍了几种厌氧反应器的特点及其在生活污水处理中的研究现状。 相似文献