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11.
溶气吹脱法处理钽铌生产氨氮废水   总被引:1,自引:0,他引:1  
用溶气吹脱法对某公司钽铌生产废水进行处理,分析了pH值、温度、时间和通气量等因素对氨氮去除率的影响。在实验条件为pH=9、温度为50℃、时间为45min、通气量为2.5L/min时,氨氮的去除率达到90%以上。  相似文献   
12.
传统文化和国防精神具有深刻的内涵。它们之间存在着必然联系,传统文化对国防精神产生着正、负两个方面的影响。  相似文献   
13.
国防是国家生存发展的安全保障,高校是培养高素质人才的重要基地,国防教育是素质教育的重要内容,国防素质是高素质人才应有的素质,加强高校国防教育是培养高素质人才的必然要求。  相似文献   
14.
This paper provides new empirical evidence on delinking and Environmental Kuznets Curves (EKC) for greenhouse gases and other air pollutant emissions in Italy. A panel dataset based on the Italian NAMEA (National Accounts Matrix including Environmental Accounts) for 1990–2001 is analysed. The highly disaggregated dataset (29 production branches, 12 years and nine air emissions) provides a large heterogeneity and can help to overcome the shortcomings of the usual approach to EKC based on cross-country data. Both value added and capital stock per employee are used as alternative drivers for analysing sectoral NAMEA emissions. Trade openness at the same sectoral level is also introduced among the covariates. We find mixed evidence supporting the EKC hypothesis. The analysis of NAMEA-based data shows that some of the pollutants such as two greenhouse gases (CO2 and CH4) and CO, produce inverted U-shaped curves with coherent within-range turning points. Other pollutants (SOX, NOX, PM10) show a monotonic or even N-shaped relationship. Macro sectoral disaggregated analysis highlights that the aggregated outcome should hide some heterogeneity across different groups of production branches (industry, manufacturing only and services). Services tend to present an inverted N-shape in most cases. Manufacturing industry shows a mix of inverted U and N-shapes, depending on the emission considered. The same is true for industry (all industries, not only manufacturing): although a turning point has been experienced, N-shapes may lead to increased emissions with respect to very high levels of the economic driver. In general, EKC evidence is more pronounced for greenhouse gases. The results suggest that analysis at macro sector (whole industry, manufacturing only and services) can be the most promising approach to future research on EKC.  相似文献   
15.
师俊强 《物流科技》2008,31(7):143-145
CS战略是企业经营中的顾客满意战略,是企业经营活动的基本准则。物流企业要想在市场竞争中取胜,必须以顾客为中心,积极实施顾客满意战略,通过更新经营理念,完善组织管理模式和服务体系,建立顾客信息反馈系统,加强与顾客沟通等途径,为顾客创造增值服务,不断增强顾客满意度,提高自身的竞争能力。  相似文献   
16.
The Essential Air Service Program (EAS) has attracted considerable criticism and has been a target for either modification or complete termination almost since its inception through the Airline Deregulation Act in 1978. Although its opponents emphasize the program's inefficiency, its supporters claim that the program is crucial to accessing small and remote communities, which helps them develop economically and socially. This paper demonstrates the economic contributions of EAS flights to small and remote communities. Using a two-stage least squares estimation, the major findings indicate that a 1% increase in air passenger traffic in EAS airports with a minimum annual air passenger traffic of 1000 likely leads to a 0.12% increase in per capita income of the community served by that airport. Our results also suggest that EAS communities that are able to sustain their subsidized flights experienced higher per capita income growth in the 1999–2011 period than did ex-EAS communities that lost their flights as a result of non-eligibility.  相似文献   
17.
Air and groundwater temperatures were measured in a rimstone pool in Postojna Cave, to advise evaluation of the impact of natural and anthropogenic influences related to heat being initially transmitted into cave air by visitors. Such heat can accumulate both in the rock mass and in water. Results show that attention must be paid to temperature changes of rimstone pool water rather than those of cave air, especially during the winter. Thanks to good ventilation deep inside the cave, short-term air temperature increases related to higher visitor numbers have not influenced flowstone precipitation or the cave fauna. However, this situation might change if winter visitor numbers increased greatly. This study does not support a suggested increase in winter visits (currently the tourism low-season) and reduction of summer visits (currently the tourism high-season).  相似文献   
18.
An economic growth target is a declaration by policy authorities of commitment to that target and the corresponding allocation of resources. The constraints created by economic growth target are an important economic management method in China, which has helped China's economy to achieve remarkable achievements. However, it has also brought about serious environmental problems, threatening China's sustainable development. Using the data about economic growth targets in the work reports of 30 Chinese provincial governments from 2006 to 2017, this paper constructs several spatial measurement methods, such as the spatial Durbin model, to examine the constraints created by economic growth target's impacts on air pollution. The main conclusions are as follows. First, a significant “U-shaped” relationship exists between the constraints created by economic growth targets and air pollution. Second, the spatial Durbin model analysis revealed that PM2.5 across China's provinces display significant positive spatial spillover effects and spatial agglomeration characteristics. Third, the direct, indirect, and total effects of constraints created by economic growth targets on air pollution are all statistically significant and depict a “U shape.” Finally, the constraints created by economic growth targets have an apparent threshold effect on air pollution, and the inhibiting effects increase with human capital and industrial restructuring. However, with the increase in foreign direct investments, constraints created by economic growth targets may increase air pollution. The conclusions of this paper are of great significance for improving the management of local government economic growth targets and sustainable development.  相似文献   
19.
This paper employs matching techniques to investigate the effects of facility export status on environmental performance. Using facility-level criteria air emission data in the US manufacturing industry, we find the industry-specific effects of export status on emission intensity, measured by emissions per value of sale. In some industries, there is consistent and robust evidence supporting the superior environmental performance of exporters relative to non-exporters in terms of emission intensity for all criteria air pollutants tracked. In other industries, we find weak evidence that exporters appear to have a higher emission intensity than non-exporters. This industrial heterogeneity in the effects of exporting on the environment is closely related to industrial characteristics including pollution abatement capital expenditure, trade costs, capital intensity and others.  相似文献   
20.
一种基于区间数向量投影的主要防御方向选择方法。针对评价指标属性和权重的区间数,构造正理想方案,计算各方案在正理想方案的投影值,根据投影值完成方案的排序优选。实例分析验证了其有效性和适用性。  相似文献   
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