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排序方式: 共有108条查询结果,搜索用时 16 毫秒
1.
本文根据胶质含量测定试验方法的要求,以车用汽油中胶质含量(包括未洗胶质含量和溶剂洗胶质含量)测定为例,探讨了0.5单位数值修约、极限数值的表示和判定在胶质含量测定数据处理和结果判定中的应用。目的在于使车用汽油产品检测工作中在数据处理、报告和结果判定方面更加规范和统一。  相似文献   
2.
This paper examines the link between fuel prices and sales of cars and trucks. U.S. automakers have long denied that such a link exists. One source of this false belief is an obsession with the crude count of units sold, equating Hummers with Minis. Another source is the conventional “wisdom” that Americans are unwilling to pay for fuel economy. The paper presents theoretical reasons and market evidence that refute Detroit’s conventional wisdom. American manufacturers’ reaction to rising fuel prices over the last few years revealed the shortcomings of the U.S. automakers’ recent product and powertrain strategies. The effect of rising fuel prices has, in effect, been offset by reducing prices of vehicles in inverse proportion to fuel economy. Thus, unit sales of large SUVs could be maintained, but their revenue (and profit) fell because vehicle prices were cut, directly or indirectly. The paper concludes with a few practical guidelines that business economists should use to prevent their companies from experiencing the recent massive losses experienced by the U.S. automobile industry. JEL Classification D120  相似文献   
3.
郭仕莲 《化工科技市场》2006,29(7):23-25,29
研制出以物质A和氧化铝为复合载体,以钨-镍为活性组分的柴油加氢精制催化剂;以大庆重油催化轻柴油为原料,在反应压力7.0 MPa,氢油体积比500:1,体积空速0.8h-1,反应温度330℃的工艺条件下,生成油硫含量<15μg/g,满足世界燃油规范Ⅲ类清洁柴油标准.  相似文献   
4.
针对240万吨/年柴油精制装置反应器温升小,加热炉负荷高,燃料消耗高等问题,延安石油化工厂通过分析原因,增设了FCC/DCC油专线。原料油中掺炼FCC/DCC油后,反应器温升提高了8℃以上,有效解决了加热炉负荷高的问题,消除了安全隐患。  相似文献   
5.
Recognizing policy-making process as a communicative process, this study examines who has subsidized information relating to the net neutrality policy debate. Empirical data has been collected from net neutrality stories published in four national newspapers, as well as from hearings by Congress and the Federal Communications Commission (FCC), during the period of February 2004 through January 2009. Study findings reveal that corporate interests have played a significant role in subsidizing information on net neutrality, both to the public through the mainstream media and to legislators through Congressional hearings. Furthermore, study results show that experts played a larger role in defining net neutrality through the mainstream media and FCC hearings than they did through Congressional hearings. Finally, the role of advocacy group representatives was more apparent at Congressional hearings than via the other two available information channels.  相似文献   
6.
通过对GB19730---2011《车用汽油》标准的解读,解析了标准的修订内容,指出了第Ⅲ与第Ⅳ阶段汽油技术指标的主要差异;阐述了标准的颁布缩小了与先进国家在车用汽油技术指标上的差距,为规范和提高我国车用汽油的质量提供了依据;分析了标准的实施对炼油企业汽油的生产及检验带来的影响。  相似文献   
7.
The gasoline crises of the 1970s demonstrated the need for including gasoline prices and gasoline shortages in models explaining retail sales. In this article, a model is constructed that incorporates the aforementioned variables, other variables, and a lagged sales figure as independent variable. The results indicate a high degree of explanatory power in predicting retail sales for a specialty store chain with a preponderance of their stores in large regional malls that sell a product which lends itself to unplanned purchase behaviour.  相似文献   
8.
自从1998年起,中国成品油市场定价机制已经进行了四次改革,市场定价将是未来的发展趋势。但是鉴于现在成品油市场尚处于寡头垄断的市场结构,完全放松管制可能出现无法预料的严重后果,采用基于Agent的计算经济学的方法,建立了基于信念学习的中国汽油市场模型,并重点分析了垄断溢价形成的影响因素,以及消费者的刚性需求和收入约束对消费者福利的影响。通过对不同原油价格水平下汽油市场的模拟,得到了描述消费者生存率的二次方程。通过建立虚拟变量模型,发现当消费者决策受收入约束时,油价、收入和刚性需求对其福利的边际影响都相应变小。模型的结果对燃油税政策的制定有一定的参考意义。  相似文献   
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10.
SUMMARY

Studies of mass media show that sexual content has increased during the past three decades and is now commonplace. Research studies have examined the sexual content of many media, but not talk radio. A subcategory of talk radio, called “shock jock” radio, has been repeatedly accused of being indecent and sexually explicit. This study fills in this gap in the literature by presenting a short history and an exploratory content analysis of shock jock radio. The content analysis compares the sexual discussions of two radio talk shows: Infinity's Howard Stern Show and Clear Channel's Bob & Tom Show.  相似文献   
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