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1.
ABSTRACTThis article identifies the breakdowns in the covariance of three benchmark crude oil futures markets (WTI, Brent and Dubai) and investigates the changes of market connectedness across the breakdown periods. As the crude oil futures are traded in different regions, this article eliminates the non-synchronous trading data by employing the Vector Moving Average structure and the Bayesian data augmentation approach, which keeps the integrity of original data without changing its properties. The results show that there are significant breaks in the covariance structure of crude oil futures markets. The breakdown periods are consistent with the periods when the market volatilities are at high level and the returns are volatile. The changes of market connectedness are independent of the covariance states, which supports the globalization hypothesis for the crude oil market. The results also suggest that there is more information flow out of the WTI than to the WTI during the sample period, particularly during the breakdown periods in 2008–2009. 相似文献
2.
Juan Equiza-Goñi 《Applied economics letters》2019,26(11):919-926
In this paper, we investigate the impact of oil prices on both aggregate and industry US real stock returns over the period 1973–2017. The empirical analysis contributes to the related literature introducing a state-dependent oil price (high and low) and the local projections approach. Our main finding is that, depending on the nature of the shock and industry, the negative effects of oil price shocks become exacerbated -and the positive effects get moderated- if oil prices are already high. 相似文献
3.
郭娜 《石油化工技术经济》2005,21(2):49-52
文章通过综合分析各类影响因素,并借鉴历史经验教训,考虑其现实条件和管理要求,认为中石油存续公司适宜采取集权式财务管理。并从财务机制、财务制度等方面进行改革和创新,制定并实施相关的保证措施,以确保集权式财务管理体制能够有效运行。 相似文献
4.
环保型水性上光油的研制与应用 总被引:1,自引:0,他引:1
目前,涂布上光技术已被越来越多的印刷厂家所采用,促使上光油的需求量不断上升。经过近几年的努力,我院研制的环保型水性上光油已取得了突破性的进展,完全能够替代溶剂型水性上光油和油性上光油,由于水性上光油具有无毒、无味、透明感强、无有机挥发物(VOC)的排放,成本低、原材料来源广等特点,在使用中能赋予印刷良好的光泽性、耐折性、耐磨性和化学品性,尤其是它所具有的环保性能特别适合食品、药品和烟草等行业包装印刷材料的加工。 相似文献
5.
Gabriella Phiri Peter Mumba Agnes Mangwera 《International Journal of Consumer Studies》2006,30(6):527-532
A survey was conducted in Lilongwe city urban markets in Malawi, to assess the quality of cooking oil used for frying potato chips. Purposive sampling was performed to come up with respondents who were using vegetable oils. A stratified random sampling was used to select the 32 informal food processors who were interviewed using a structured questionnaire. Oil samples were collected from the most commonly used brand of oil. Fifteen respondents were selected and these were divided into three categories of five: those who were not reusing the oil, those who were reusing the oil and those who were preparing potato chips and chicken in the same oil, for chemical analysis. The preliminary results showed that while the majority (59.4%) of the informal food processors discarded the oil after 1 day, 3.1% discarded it after 4 days and another 12.5% after 3 days. A larger proportion of the respondents (40.6%) used the leftover oils at home, 37.5% kept it in oil bottles, 3.1% kept it in plastic papers for reuse the following day. Also, most respondents (57%) indicated dark colour as the sign of oil deterioration, 29% discarded the oil after noticing foam formation while 8.2% and 6.1% said they discarded the oil after noticing a bad smell and food absorbing the oils respectively. A physical observation of the various oils showed that for most of the respondents (34%), the oils were dark brown in colour, in 22%, the oils were slightly dark brown and 16%, the oils were brown. Foam formation was noticed in 13% of the respondents. It was also noted that 91% of the respondents had not been trained or briefed of food quality and safety issues. A chemical analysis of the oils showed high values of free fatty acids (range, 0.84–1.4112 compared with 0.42 in the fresh oil) and peroxide values (range 14.7–16.6 compared with 9.0 in the fresh oil). It may be concluded that the oils being used by the informal food processors in Malawi are of poor quality and so the foods cooked in them may be a health hazard to the consumers and the processors themselves. Although this work in ongoing, it may be recommended at the outset that the health department of the city assemblies should inspect these oils for the good health of the consumers. 相似文献
6.
Understanding the Large Negative Impact of Oil Shocks 总被引:1,自引:0,他引:1
This paper offers a plausible explanation for the close link between oil prices and aggregate macroeconomic performance in the 1970s. Although this link has been well documented in the empirical literature, standard economic models are not able to replicate this link when actual oil prices are used to simulate the models. In particular, standard models cannot explain the depth of the recession in 1974–75 and the strong revival in 1976–78 based on the oil price movements in that period. This paper argues that a missing multiplier-accelerator mechanism from standard models may hold the key. 相似文献
7.
指出规格仪器是油品测试方法标准化的基础,总结了油品测试用规格仪器国产化的过程,并对今后的发展方向加以分析。 相似文献
8.
介绍了重油悬浮床加氢裂化工艺的最新发展,对国内新开发的悬浮床加氢裂化工艺特点作了介绍。并将悬浮床加氢和三种重油轻质化工艺——固定床加氢、延迟焦化、重油催化裂化在技术经济上作了分析对比。在原油品质越来越差的今天,针对劣质重油而开发的的悬浮床加氢裂化工艺具有非常广阔的应用前景。 相似文献
9.
我国成品油定价机制经历了一个漫长的改革历程,从计划经济下的单一价格发展成为目前的逐渐向国际油价靠拢。文中阐述了每个阶段的特征和影响,并对现行成品油定价机制的特点和不足及未来的改革方向作出了分析。 相似文献
10.
介绍、比较了世界各国对能源课税,保护环境、节约能源的情况,分析了近年来发达国家能源税制改革的新趋势。指出随着我国能源消费的剧增和对进口能源的依赖加重,节能和环保方面的税收政策应受到普遍重视,应借鉴国外经验,完善我国的能源税制。 相似文献