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1.
ABSTRACT

This 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.
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.
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  
金振华 《化工科技市场》2003,26(3):26-27,23
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.
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.
周立  熊志坚 《价值工程》2007,26(3):128-131
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   
9.
位于扬子地台北缘的武当推覆体是南秦岭造山带的重要组成部分,它经历了漫长的构造演化历程。该区的层固性结构和加里东—晋宁期的伸展滑脱作用造成了武当群构造堆垛岩系的形成,华北板块和扬子板块在印支运动期间的会聚、碰撞造山作用使武当巨型推覆体逐渐形成,至喜山运动时期完全定位。本文分析了这些构造运动所产生的变形效应及构造变形的复合关系,揭示了本区变形环境由低温高压或高应变速率环境向中温低压及低温低压过渡的特征,阐述了武当推覆体的形成、武当群岩系的变形效应与动力作用方式、变形岩石的边界条件、变形岩石的结构构造以及力学性质的关系,把武当群的形成、武当推覆体的演化分为三期五个阶段,其构造变形的主要动力来源为沿大陆边坡的重力滑动和陆-陆碰撞的挤压作用,其应力作用方式为由上述动力所产生的近南北向伸展和近南北向挤压两大地应力场的转化。  相似文献   
10.
人力资本在现代企业中的作用越来越重要,使得人力资本拥有者也象财务资本所有者那样有权利要求参与企业的剩余分配。人力资本应该以什么形式、方法和方式参与企业剩余的分配是值得认真探讨的问题。  相似文献   
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