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991.
992.
低温余热的充分利用能够有效提高能源的利用效率、降低生产企业的能耗。本文以含硫天然气净化厂生产过程产生的余热为研究对象,对余热资源品位、余热回收潜能进行了分析和评价。通过对不同的余热发电方案进行分析对比,提出了以有机朗肯循环(ORC)为基础的多品位余热发电方案(MG-ORC),并对该发电方案进行了热力学分析。借助正交实验手段和多目标优化方法,对不同循环工质条件下MG-ORC发电方案的性能进行了对比分析,结果表明:工质R-600较其余4种工质表现出更优的综合性能,MG-ORC发电系统热效率为17.7%,净输出功率约2600kW。MG-ORC发电方案能够有效合理利用含硫天然气净化厂产生的余热,实现了能源的按质用能和梯级利用。 相似文献
993.
994.
针对瓦斯涌出量受多因素影响,传统的预测方法难以建立准确的数学模型,导致预测精度低这一问题。提出一种经改进的粒子群算法(MPSO)优化的基于柯西分布加权的最小二乘支持向量机(CWLS-SVM)算法来预测非线性动态瓦斯涌出量。柯西分布加权的最小二乘支持向量机根据预测误差的统计特性,确定加权规则参数,以达到赋予训练样本不同权值的目的。并用MPSO算法对CWLS-SVM模型的正则化参数λ和高斯核参数σ寻优。利用无线传感器网络采集到的各项历史数据进行实例分析。结果表明,该算法有效的提高了瓦斯涌出量的预测精度,降低了预测误差,为煤矿瓦斯防治提供理论支持。 相似文献
995.
996.
997.
A novel process was developed for the bitumen emulsion upgrading, wherein emulsion breaking and upgrading occurred in the same reactor using H2 generated in situ from the water in the emulsion via the water gas shift reaction (WGSR). In this study, dibenzothiophene (DBT) was chosen as a model compound to investigate the effect of water and in situ H2 on hydrodesulfurization (HDS). All the experiments were performed in a 1-L autoclave reactor at temperatures between 300 and 380 °C using in situ H2 and ex situ H2 (externally supplied H2) over a dispersed Mo catalyst formed from phosphomolybdic acid (PMA). At very low water content, water was found to promote the HDS reaction in the ex situ H2 run probably because it facilitates the formation of more active dispersed MoSx species. At higher water content, however, water inhibits every individual reaction in the reaction network in the HDS of DBT, blocking the hydrogenation pathway more than the hydrogenolysis pathway. The relative reactivity of the in situ and ex situ H2 depends on the water content present in the reaction system. At an optimized mole ratio of H2O:CO (1.35), higher HDS activity was observed in the in situ H2 run compared to ex situ H2 run, and particularly, the hydrogenation pathway was promoted in the in situ H2 run. 相似文献
998.
Passing of a triangular moderate-intensity pulse through a constant discontinuity is considered. Decay of the shock wave that
passed into the second gas is analyzed. Damping of the detonation wave after burnout of the combustible mixture is discussed.
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Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 4, pp. 102–107, July–August, 2007. 相似文献
999.
Ion beam irradiation can be used to modify the structure and gas transport properties of glassy polymers. This is the first of two studies that focus on the impact of H+ ion irradiation on the structure and permeation properties of the polyimide Matrimid®. Specifically, the evolution in chemical structure after H+ irradiation over a range of fluences was analyzed using FTIR spectroscopy and dissolution studies. Although H+ ion irradiation at very low ion fluences induced little modification in the chemical structure, irradiation at relatively high ion fluences resulted in crosslinking of the irradiated films. The branched structure of the aliphatic methyl (CH3) was the most sensitive to the H+ ion irradiation. The para‐disubstituted aromatic ring showed the strongest resistance toward ion irradiation and required fairly high doses to induce degradation. Two potential crosslinking mechanisms related to the degradation of the aliphatic methyl and the benzophenone carbonyl were presented. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2010–2019, 2003 相似文献
1000.
Mei‐Rong Huang Sheng‐Xian Li Zhi‐Qing Dong Wei Feng Xin‐You Wang Shu‐Ying Gu Yan‐Hui Wu Xiang‐An Huang 《应用聚合物科学杂志》2002,83(14):3013-3021
Several multilayer thin low‐density polyethylene (LDPE) films were fabricated by blown thin film having a thickness of 7 μm and an area of 130 cm2. They were characterized for their oxygen‐enrichment performance from air by a constant pressure–variable volume method in a round permeate cell with an effective area of 73.9 cm2. The relationship between oxygen‐enrichment properties, including oxygen‐enriched air (OEA) flux, oxygen concentration, permeability coefficients of OEA, oxygen, nitrogen, as well as separation factor through the multilayer LDPE films, and operating parameters, including transfilm pressure difference, retentate/permeate flux ratio, temperature, as well as layer number, are all discussed in detail. It is found that all of the preceding oxygen‐enrichment parameters increase continuously with an increase of transfilm pressure difference from 0.1 to 0.65 MPa, especially for the trilayer and tetralayer LDPE films. The oxygen concentration and separation factor appear to rapidly increase within the retentate/permeate flux ratio below 200, and then become unchangeable beyond that, whereas the OEA flux and the permeability coefficients of OEA, oxygen, and nitrogen seem to remain nearly constant within the whole retentate/permeate flux ratio investigated, especially for the monolayer and bilayer LDPE films. The selectivity becomes inferior, whereas the permeability becomes superior, as the operating temperature increases from 23 to 31°C. The highest oxygen concentration was found to be 44.8% for monolayer LDPE film in a single step with air containing oxygen of 20.9% as a feed gas and operating pressure of 0.5 MPa at a retentate/permeate flux ratio of 340 and 23°C. The results demonstrate a possibility to prepare an oxygen‐enriching membrane directly from air, based on the easily obtained thin LDPE films. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 3013–3021, 2002; DOI 10.1002/app.2331 相似文献