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81.
The Organic Rankine Cycle (ORC) is a well-established way to recover energy from a single waste heat source. This paper aims to select the suitable configuration, number of loops, and working fluids for the Multi-Loop ORC (MLORC) by using multi-objective optimization. The thermodynamic and economic performance of MLORC in three various configurations was analyzed. Multi-objective optimizations of the series and parallel MLORC using different working fluid groups were conducted to find the optimal configuration, number of loops, and working fluid combination. The analysis results show that the series–parallel MLORC performed the worst among the three configurations. The optimization results reveal that series MLORC has a higher exergy efficiency than the parallel MLORC. The exergy efficiency of the optimal solution in series dual-loop, triple-loop, and quadruple-loop ORC is 9.3%, 7.98%, and 6.23% higher than that of parallel ORC, respectively. Furthermore, dual-loop is the optimal number of cycles for recovering energy from a single heat source, according to the grey relational grade. Finally, the series dual-loop ORC using cyclohexane\cyclohexane was the suitable configuration for utilizing a single waste heat source. The exergy efficiency and levelized cost of electricity of the series dual-loop ORC with the optimal parameters are 62.18% and 0.1509 $/kWh, respectively. 相似文献
82.
A new magnetic polymer nanocomposite based on Fe3O4 nanoparticles and nature rubber was prepared by the in situ latex method. This process was fast, versatile, reliable, safe, environmentally friendly, and inexpensive. The magnetorheological effect and mechanical properties of magnetic polymer nanocomposites were investigated in detail. The tensile strength of magnetic polymer nanocomposites without other reinforcing fillers was about 14.6 MPa. At the same time, the relative and absolute magnetorheological effect was about 365.0% and 3.64 MPa, respectively, which were almost 10 times with respect to other magnetic polymer nanocomposites based on nature rubber. Furthermore, the relationships between microstructure and mechanical behavior of magnetic polymer nanocomposites were simulated and discussed by the numerical treatment of a new theoretical model associated with finite element analysis for explaining the micro‐mechanism of magnetic polymer nanocomposites with high performance. The work did not only provide a universal route for the rational design and preparation of magnetic polymer nanocomposites with simultaneously high magnetic sensitivity and mechanical properties for various applications but also propose a new method to improve dispersion of magnetic particles in nature rubber for various applications. 相似文献
83.
Bing Dong Zhen Han Yongbo Zhang Youyi Yu Prof. Aiguo Kong Prof. Yongkui Shan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(6):2046-2050
Methane is a most abundant and inexpensive hydrocarbon feedstock for the production of chemicals and fuels. However, it is extremely difficult to directly convert methane to higher hydrocarbons because the C?H bonds in methane are the most stable C?H bonds of all hydrocarbons. The activation of the C?H bonds in methane by using an efficient and mild route remains a daunting challenge. Here, we show that the inner surface structures of the pore walls in mesoporous α‐Fe2O3 possess excellent catalytic performance for methane activation and convert C?H bonds into the C?O bonds in an O2 atmosphere at 140 °C. We found that such unusual structures are mainly comprised of turbostratic ribbons and K crystal faces and have higher catalytic activity than the (110) plane. These results are without precedent in the history of catalysis chemistry and will provide a new pathway for designing and preparing highly efficient catalytic materials. 相似文献
84.
85.
两亲性梳状聚醚硅氧烷对相转化法聚偏氟乙烯多孔膜的共混改性作用研究 总被引:1,自引:0,他引:1
以聚醚链段为侧链的两亲性梳状聚醚硅氧烷(ACPS)为改性剂,研究了相转化法制备聚偏氟乙烯(PVDF)多孔膜的改性效果与机理.采用SEM、XPS、接触角、水通量等考察了ACPS对膜结构与性能的影响.研究发现,ACPS在相转化成膜过程中不流失,随着制膜液中ACPS含量的增加,相分离速度降低,膜中微孔由指状结构向蜂窝状结构发展,膜强度提高,亲水性显著提高.提出了ACPS在膜表面的富集现象和在膜中的稳定性机理和模型.结果表明,两亲性梳状聚醚硅氧烷在原理上是一类适合于相转化法制备聚合物微孔膜表面亲水化改性的有效物质. 相似文献
86.
该文叙述的是把多重网格法应用于反应堆扩散方程的一个准备性工作。我们应用V循环和W循环的多重网格法求解一个模型问题,并与SOR方法进行了比较。数值结果表明,W循环的多重网格法要比SOR方法快四倍。 相似文献
87.
Qizhi Wang Dongsheng Zhou Ming Wang Youyi Zhao Yu Chen Min Yin Xu Feng 《Chemistry of Natural Compounds》2014,50(3):531-533
88.
Xinfeng Zhao Qian Li Chaoni Xiao Yajun Zhang Liujiao Bian Jianbin Zheng Xiaohui Zheng Zijian Li Youyi Zhang Taiping Fan 《Analytical and bioanalytical chemistry》2014,406(12):2975-2985
A method based on reaction with a diazonium salt was developed to immobilise oriented His-tagged protein onto silica gel. The binding efficiency of the phenylamine-group-coated gel was determined to be 65 %, providing a binding capacity of His-tagged protein up to the gram level. Using His-tagged β2-adrenoceptor (β2-AR) as a probe, we developed a new mathematical model to elucidate the interactions between the receptor and five ligands (methoxyphenamine, terbutaline, salbutamol, tulobuterol and fenoterol). These drugs proved to only have one type of binding site on the immobilised β2-AR, yielding higher association constants and numbers of binding sites than random attachment assays. The association constants determined by the new model positively correlated to the values from a radioligand binding method, with a regression equation of y?=?1.75x???7.18 and a correlation coefficient of 0.9807. The oriented method resulted in a high binding capacity and quantitative immobilisation of the His-tagged protein. The proposed model can be used to determine the interactions between the ligands and the immobilised protein with the advantages of drug and time saving. Figure
Oriented immobilisation of histidine-tagged protein by diazo reaction 相似文献
89.
We consider a two-level inventory system in which there are one supplier and multiple retailers. The retailers face stochastic, interdependent customer demands. Each location employs a periodic-review (R,nQ), or lot-size reorder point, inventory policy. We show that each location's inventory positions are stationary and the stationary distribution is uniform and independent of any other's. 相似文献
90.
Wang Y Yuan B Deng X He L Wang S Zhang Y Han Q 《Analytical and bioanalytical chemistry》2006,386(7-8):2003-2011
A G-protein-coupled receptor-cell-membrane stationary phase (CMSP) has been prepared by immobilizing cell membranes on the
surface of silica, as carrier. The resulting HEK293
α
1A
adrenoceptor cell-membrane stationary phase can be used for rapid on-line chromatographic determination of potential subtype-selective
α
1
-adrenoceptor ligand-binding affinities for α
1
-adrenoceptor subtypes. The objective of the research was to study whether cell lines stably overexpressing subtype receptors
could improve the sensitivity and specificity of cell-membrane chromatography (CMC) compared with use of homogenized tissue
and cells in primary culture. Effects of mobile-phase ionic strength, sample concentration, and the presence of competitive
agents on ligand-receptor interaction in CMSP were also evaluated. We found that cell lines stably overexpressing subtype
receptors led to improved sensitivity and specificity in CMC. The technique leads to useful procedures-cell-membrane stationary
phases may, for example, facilitate exploration of ligand-receptor interaction and determination of ligand-receptor binding
affinity in initial screening and separation of lead compounds or active components in Chinese traditional natural medicine
and herbs. This might eventually be an important contribution and an addition to our collection of techniques. 相似文献