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排序方式: 共有1384条查询结果,搜索用时 15 毫秒
1.
本文建立了包菜中对硫磷残留量的气相色谱-火焰光度检测器(FPD)检测方法.样品用QuEChERS方法进行前处理后,采用外标法进行定量.对硫磷在80.0~1000μg·L-1范围中线性关系良好(r=0.9994),方法添加回收率为96.0%~111%,相对标准偏差RSD为2.5%~4.3%,方法的检出限为0.161μg·kg-1,能够满足蔬菜中对硫磷残留量的分析要求. 相似文献
2.
《Socio》2021
The present inquiry lays a groundwork for the analysis of the net greenhouse gas (GHG) footprint of oil in the oil-abundant settings. To address the research question, the study puts forward a three-sector decision model, which provides a common ground for the assessment of the interaction of the structuralist and institutional factors influencing environmental pollution in the oil-reliant economies. The study shows that fossil-fuel abundance triggers forces, which induce diametrically opposed effects concerning atmospheric pollution. These are the rising carbon-intensive oil extraction and processing and fossil-fueled power generation versus shrinkage of the carbon-intensive manufacturing and growth of the low-carbon tertiarization. The theoretical analysis enables compartmentalization of the essential factors, which determine GHG emissions in the respective countries. To assess the significance of the proposed theoretical framework, the study employs multivariate panel co-integration techniques and two-stage fixed effects estimations for a dataset of 38 oil-producing countries for the time period between 1960 and 2018. In contrast to the existing literature, this study drives apart from the black box approaches that employ just one omnibus variable, per capita income. 相似文献
3.
张献召 《中小企业管理与科技》2021,(6)
论文主要分析了页岩的地质情况,结合其特征,分析气储层的特殊性。论文通过总结当前存在的问题,分析与总结经验,探究页岩气储层录井技术的要点。论文提出页岩气储层的岩石内硅质成分占比较高,且钙含量也比较高,岩石既坚硬又脆弱,在钻井阶段,要使钻井速度保持在较高水平。通过合理使用综合气相色谱仪,可发现油气开发过程中存在的问题,其应用优势比较明显。 相似文献
4.
李向前 《中小企业管理与科技》2021,(4)
2020年新冠疫情期间,部分燃气企业借助信息化系统优势,在落实防疫措施的同时,切实地保障了民生用气。论文阐述了燃气企业信息化系统的组成、在新冠疫情影响下展现的优势及小型燃气企业信息化推广面临的困难,强调了信息化建设对燃气企业管理水平、竞争能力提升的重要性。 相似文献
5.
Yujin Beak Kayoung Kim Kyuho Maeng Youngsang Cho 《Business Strategy and the Environment》2020,29(3):996-1006
In a bid to reduce greenhouse gas emissions, several countries worldwide are implementing policies to promote electric vehicles (EVs). However, contrary to expectations, the diffusion speed of EVs has been rather slow in South Korea. This study analyzes consumer preferences for the technological and environmental attributes of EVs and derives policy and environmental implications to promote market diffusion of EVs in South Korea. We conduct a choice‐based conjoint survey of 1,008 consumers in South Korea and estimate the consumer utility function using a mixed logit model considering consumer heterogeneity. Based on the consumer utility function, we analyze consumers' willingness‐to‐pay (WTP) for EV attributes such as driving range, charging method, charging time, autonomous driving function, carbon dioxide (CO2) reduction rate, and purchase price. The results indicate that the current low acceptance of EVs is due to their relatively high price and lack of a battery charging technology that satisfies consumers' expectations of the charging method and time. One interesting finding is that Korean consumers have a relatively higher WTP for the CO2 reduction rate of EVs than consumers in other countries; however, they do not consider CO2 reduction over other technological attributes when choosing EVs. This implies that the rate of CO2 reduction of EVs is not an important factor for South Korean consumers when buying EVs. We also calculate the effect of CO2 reduction with the market penetration of EVs and find that CO2 reduction through the diffusion of EVs depends on the country's electricity generation mix. 相似文献
6.
Cássio G. Ribeiro Edmundo Inacio Junior Yanchao Li Andre Furtado Nanci Gardim 《Technology Analysis & Strategic Management》2020,32(2):119-132
ABSTRACTThis paper analyses the role of user-supplier relationships in the innovation dynamics of the Oil and Gas (O&G) industry, from an analysis supported by R&D and patent application data. This paper points to some recent interesting phenomena in the O&G sector, such as: (i) the remarkable advancement of two Chinese oil companies; (ii) the significant growth in O&G companies’ technological engagement in exploration and production (E&P) from the 2000s; (iii) the non-negligible increase in the application of O&G companies’ patents for renewable energy. Moreover, by working with the oil and gas chain complete, we show that the performance of the companies oil and gas equipment and services industry (O&GES) is restricted to the upstream activities. Finally, we bring up some arguments that have as objective relativise the typology of R&D intensity adopted by OECD. 相似文献
7.
2019年,俄罗斯油气工业发展基本平稳,原油产量为5.60亿吨,比上年增长0.8%;原油一次加工量为2.85亿吨,比上年减少0.4%,出口量为2.68亿吨,比上年增加2.8%。天然气产量为7376亿立方米,比上年增加1.7%;天然气出口量为2199亿立方米,比上年减少0.3%;LNG产量和出口量分别达到2950万吨和2900万吨,较2018年分别增长47.4%和76.2%;天然气出口管道建设取得突破,中俄东线天然气管道和土耳其流天然气管道建成投产,实现出口供气。俄政府批准新版的《俄罗斯能源安全论》,明确了能源安全的目的、原则及重点方向与任务;批准车用天然气燃料市场发展规划,加快推动俄国内车用天然气燃料市场发展;通过《俄罗斯2035年能源发展战略》,明确了俄能源战略的5个关键目标。 相似文献
8.
伴随着供应链管理的应用与发展,越来越多的企业认识到必须充分利用内外资源保持自身的竞争实力。作为重要的外部资源,供应商管理关系到企业成本与收益的平衡,而要做好供应端的成本管理首先要做好供应商的选择和优化。针对CS公司的供应商管理现状及存在的问题,探索适应企业的可操作性强的对策,以期为我国大型油气企业的供应商管理实践提供一定的参考。 相似文献
9.
ABSTRACTThe implications of national or regional energy policies for technical efficiency and environmental outcomes in electricity generation depend on fossil fuel input substitution. This study uses state level data to examine fossil fuel (coal and natural gas) substitution in electricity generation under increased availability of natural gas in the United States. We observe that changes in elasticities of substitution from pre-2009 to post-2009 differ across states suggesting that the effects of increased availability of inexpensive natural gas on electricity generation have been spatially heterogeneous. We rely on the observed heterogeneity to assess the effects of fossil fuel input substitution on technical efficiency and CO2 emissions. The results reveal that state level elasticity of substitution between natural gas and coal has a positive effect on technical efficiency and a negative effect on CO2 emissions. Therefore, future policy design and analyses should reflect the implications for regional elasticities of fossil fuel substitution and associated environmental outcomes. 相似文献
10.
Yan Liu 《International Journal of Sustainable Transportation》2018,12(7):473-483
This article employs an integrated discrete-continuous car ownership model to jointly forecast households’ future preferences on vehicle type, quantity and use, and to estimate greenhouse gas (GHG) emissions. The model system is estimated on a dataset collected from a web-based stated preference survey conducted in Maryland in 2014. The data contain vehicle purchase decisions and sociodemographic information of 456 households who were requested to state their future preferences over a 9-year period (2014–2022). In each time period, a respondent is faced to four alternatives that include the current vehicle, a new gasoline vehicle, a new hybrid electric vehicle, and a new battery electric vehicle. Intertemporal choices between conventional and “green” vehicles such as hybrid and electric cars capture dynamics in vehicle purchase decisions. Short run and medium-long run situations were predicted and compared based on the first 4-year data and the entire 9-year data of the dynamic panel. Vehicle GHG emissions were calculated correspondingly. We find the introduction of “green” vehicles makes a positive impact on car ownership and use, especially in a medium-long run. Two “green” taxation policies, gasoline tax and ownership tax, were proposed and their impact on vehicle use and emission reductions was evaluated. Results indicate that: (a) gasoline tax is a more effective way to reduce vehicle miles traveled and GHG emissions and (b) gasoline tax makes a higher impact on car use and emission reductions in the medium-long run, while ownership tax makes a higher impact in the short run. 相似文献