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61.
One hundred and forty-seven species of spores and pollen referred to 77 genera found in the crudeoil samples taken from four petroliferous provinces of the Tarim Basin of Xinjiang Provincehave been studied in this paper. By means of these spore and pollen fossils, the geological ages anddistribution of the petroleum source rocks of the basin are judged. Also, the principles and methodsto judge the petroleum source of a petroleum province by spore/pollen and other microfossils in crudeoils are explained. 相似文献
62.
This paper describes some thermal analysis experiments conducted on high explosive samples. These employ differential scanning calorimetry to monitor thermal effects at elevated temperatures (around 200 °C) and heat conduction calorimetry to record thermal effects at much lower temperatures (below 100 °C).The work shows that, due to the generally high thermal stability of many high explosive compositions, heat generation rates are very low, if detectable at all, at normal storage temperatures, even when using a very sensitive instrument. The sensitivity and reproducibility of this technique has been investigated in detail by Wilker et al. [S. Wilker, U. Ticmanis, G. Pantel, Detailed investigation of sensitivity and reproducibility of heat flow calorimetry, in: Proceedings of the 11th Symposium on Chemical Problems Connected with the Stability of Explosives, Sweden, 1998] and shown to be capable of recording heat generation rates of less than a microwatt. This allows continuous measurement of decomposition processes in nitrate ester based propellants at temperatures as low as 40 °C. However, the measurement of very low levels of heat generation is difficult, time consuming and therefore expensive. If the assumption is made that the life limiting process is invariably the slow decomposition of the energetic component, this will frequently lead to very long service lifetime predictions.A number of possible complications are identified. Firstly, due to its low detection threshold, a heat conduction calorimeter may detect other reactions which will not lead to failure, but which may still dominate the heat flow signal. Secondly, the true failure process may generate little energy and be overlooked. In view of these considerations, at present it seems unwise to rely on heat conduction microcalorimetry as the only tool for the assessment of the life of high explosive energetic systems.Based on examples of life terminating processes in high explosives during storage and use, it is clear that decomposition of the energetic material is not invariably the cause of system failure. It is also by no means the only reaction that may take place in, and be observed by, a heat conduction calorimeter. 相似文献
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64.
石油是一种特殊的商品,是国家重要的战略物资,世界各国都十分重视其价格变动问题,因为油价变化会影响到各国经济发展,甚至国家安全。因此,本文采用GARCH模型,通过基于Gibbs抽样的MCMC方法分析了国际市场石油价格的分布特征,对石油价格波动的异方差特性进行描述和模拟,实证分析结果说明从石油价格波动序列峰度系数和平方价格波动序列自相关函数的描述来看,基于t分布的模型模拟效果优于基于正态分布的模型,这一结论反映了石油价格波动序列的分布特性。 相似文献
65.
Train scheduling model is traditionally formulated to minimize the energy consumption for reducing the operation cost. As the European Union formulates the first carbon emission trading scheme in the world, it is necessary to extend the operation cost to include the expenses for buying/selling the carbon emission allowances. In this paper, we propose a multi-objective train scheduling model by minimizing the energy and carbon emission cost as well as the total passenger-time, and named it as green train scheduling model. For obtaining a non-dominated timetable which has equal satisfactory degree on both objectives, we apply a fuzzy multi-objective optimization algorithm to solve the model. Finally, we perform two numerical examples to illustrate the efficiency of the proposed model and solution methodology. 相似文献
66.
全要素生产率和产业结构对能源利用影响的实证分析 总被引:5,自引:0,他引:5
本文利用能源消耗模型进行实证分析,结果表明决定能源利用效率的关键因素和长期因素是全要素生产率,全要素生产率的不断提高导致了我国经济快速发展而单位GDP能源消耗不断降低的特殊现象.产业结构对能源消耗有显著的短期影响,当第一产业比例下降或第二产业比例上升时,能源消耗增加。市场化程度、对外开放程度对能源消耗的作用体现在全要素生产率中.2000年后能源消耗重新抬头并不否定全要素生产率的作用,而是缺乏节能意识的负面影响抵消并逆转了全要素生产率的正面作用. 相似文献
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本文在垂直创新模型框架下,将能耗强度和碳减排比例引入生产函数,将人们对气候变化的警惕意识引入效用函数,建立了一个动态的内生低碳经济增长模型。通过求解所建动态优化模型,找到了经济长期均衡增长的最优路径,讨论了能源强度和能源消费结构变化与经济均衡增长的相互关系,分析了各参数对经济最优增长路径的影响,比较了化石能源内部消费结构不变和逐年清洁两种情景下的经济最优增长路径的异同。长期来看,能源强度、二氧化碳减排速率与经济增长率有相互的负向线性关系,缩小反映化石能源内部消费结构的综合碳排放系数对经济增长有促进作用。非化石能源比例越高,低碳技术应用越广泛,研发成果对技术积累的贡献率越大,消费者对当前消费的偏好程度越小,人们对气候变化的警惕意识越强,则越有利于经济的低碳发展。 相似文献
70.
在国家电网公司Q/GDW 1379.4-2013技术规范对智能电能表载波通信单元功率消耗的限定要求下,为保障低压远程电力集抄台区本地通信链路的传输速率稳定可靠,给智能用电实时交互平台提供带宽支持,提出了一种裕量最大的高速载波比特功率分配算法。该算法以兼并窄带载波和宽带载波优势的G3-PLC技术为应用对象,使用约束注水法限定各子载波的传输比特数,根据时变的电力信道增益自适应调整比特功率分配方案,并响应通信服务质量QoS对系统误码率和目标传输速率的要求,结合信噪比门限算法对约束注水法进行界定和优化,得到了功率裕量最大化的表达式。仿真结果表明:提出的算法优于低反馈开销算法,能够适应低压电力线信道。在系统目标传输速率为200kbps时,达到了最大裕量值20,极大程度地降低了通信单元调制解调芯片实际的功率消耗。 相似文献