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Journal of Computer Science and Technology - DOACROSS loops are significant parts in many important scientific and engineering applications, which are generally exploited pipeline/wave-front... 相似文献
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Replacement of precious single metal catalysts with cost-effective, highly-dispersed composite catalysts for catalytic hydrothermal conversion of residue holds tremendous promise for the residue upgrading technologies. Organic metals were added to the feed as the oil-soluble precursors, and transformed into the catalytic active phases in this work. Physical properties and structures of the composite catalysts had been investigated by X-ray fluorescence spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscope and transmission electron microscopy. The composite catalysts were found to be highly efficient in the catalytic hydrothermal conversion of both model compound and residue. Increased metal dispersion and synergistic effects of two metals played indispensable roles in such catalytic system. Results showed that under the test conditions in the article, the catalyst had the best catalytic performance when the mass ratio of molybdenum to iron was 1.5. 相似文献
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Neural Computing and Applications - Traffic identification is currently an important challenge for network management and security. In this paper, we propose a novel application identification... 相似文献
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针对谱聚类融合模糊C-means(FCM)聚类的蛋白质相互作用(PPI)网络功能模块挖掘方法准确率不高、执行效率较低和易受假阳性影响的问题,提出一种基于模糊谱聚类的不确定PPI网络功能模块挖掘(FSC-FM)方法。首先,构建一个不确定PPI网络模型,使用边聚集系数给每一条蛋白质交互作用赋予一个存在概率测度,克服假阳性对实验结果的影响;第二,利用基于边聚集系数流行距离(FEC)策略改进谱聚类中的相似度计算,解决谱聚类算法对尺度参数敏感的问题,进而利用谱聚类算法对不确定PPI网络数据进行预处理,降低数据的维数,提高聚类的准确率;第三,设计基于密度的概率中心选取策略(DPCS)解决模糊C-means算法对初始聚类中心和聚类数目敏感的问题,并对预处理后的PPI数据进行FCM聚类,提高聚类的执行效率以及灵敏度;最后,采用改进的边期望稠密度(EED)对挖掘出的蛋白质功能模块进行过滤。在酵母菌DIP数据集上运行各个算法可知,FSC-FM与基于不确定图模型的检测蛋白质复合物(DCU)算法相比,F-measure值提高了27.92%,执行效率提高了27.92%;与在动态蛋白质相互作用网络中识别复合物的方法(CDUN)、演化算法(EA)、医学基因或蛋白质预测算法(MGPPA)相比也有更高的F-measure值和执行效率。实验结果表明,在不确定PPI网络中,FSC-FM适合用于功能模块的挖掘。 相似文献
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Basins with various mineral resources coexisting and enriching often occupy an important strategic position. The exploration of various mineral resources is repetitive at present due to unshared data and imperfect management mechanism. This situation greatly increases the cost of energy exploitation in the country. Traditional data-sharing mode has several disadvantages, such as high cost, difficulty in confirming the right of data, and lack of incentive mechanism, which make achieving real data sharing difficult. In this paper, we propose a data-sharing mechanism based on blockchain and provide implementation suggestions and technical key points. Compared with traditional data-sharing methods, the proposed data-sharing mechanism can realize data sharing, ensure data quality, and protect intellectual property. Moreover, key points in the construction are stated in the case study section to verify the feasibility of the data-sharing system based on blockchain proposed in this paper. 相似文献
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Jie Gao Zhikai Li Mei Dong Weibin Fan Jianguo Wang 《Frontiers of Chemical Science and Engineering》2020,14(5):847
Coal-based ethanol production by hydration of ethylene is limited by the low equilibrium ethylene conversion at elevated temperature. To improve ethylene conversion, coupling hydration of ethylene with a potential ethanol consumption reaction was analyzed thermodynamically. Five reactions have been attempted and compared: (1) dehydration of ethanol to ethyl ether ( ), (2) dehydrogenation of ethanol to acetaldehyde ( ), (3) esterification of acetic acid with ethanol ( ), (4) dehydrogenation of ethanol to ethyl acetate ( ), and (5) oxidative dehydrogenation of ethanol to ethyl acetate ( ). The equilibrium constants and equilibrium distributions of the coupled reactions were calculated and the effects of feed composition, temperature and pressure upon the ethylene equilibrium conversion were examined. The results show that dehydrogenation of ethanol to acetaldehyde has little effect on ethylene conversion, whereas for dehydrogenation of ethanol to acetaldehyde and ethyl acetate, ethylene conversion can be improved from 8% to 12.8% and 18.5%, respectively, under conditions of H2O/C2H4 = 2, 10 atm and 300°C. The esterification of acetic acid with ethanol can greatly enhance the ethylene conversion to 22.5%; in particular, ethylene can be actually completely converted to ethyl acetate by coupling oxidative dehydrogenation of ethanol. 相似文献
48.
Yue Gao Miao-miao Zhang Xiao-peng Guo Wen-jian Li Dong Lu 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2020,95(5):1290-1297
Toxicity caused by the accumulation of butanol in fermentation media is an important factor limiting the concentration of butanol. There is currently no systematic research in place investigating the butanol tolerance mechanism of bacteria such as Clostridium acetobutylicum, which adapts to butanol stress and regulates its growth and metabolism. Here, research results related to the butanol tolerance of C. acetobutylicum are reviewed to understand the molecular basis of changes in butanol-tolerant strains. Organic solvent-tolerant bacteria play an important role in the fields of biofuel production, enzyme preparation and bioremediation. An analysis of limitations of the application of organic solvent-tolerant bacteria has revealed that future research should focus on combining the microbial tolerance phenotype with specific utilization to achieve an optimal balance between organic solvent tolerance and production. This review serves as a reference for the improvement and engineering of strains that tolerate organic solvents. © 2019 Society of Chemical Industry 相似文献
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