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气升式环流反应器的特性及应用 总被引:3,自引:0,他引:3
综述了气升式环流反应器的特性及其主要影响因素研究,简要介绍了这种反应器的应用情况,并提出了今后研究工作的方向。 相似文献
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How to apply the global optimization technique, simulated annealing, and to explore the operation of batch reactors is addressed in this study. Based on the operating purposes and the imposed constraints, the batch reactor operations are first formulated as two optimal control problems: the maximal yield (or conversion) problem and the minimal operating time problem. The problems are then converted into non‐linear programming problems by the concept of control vector parameterization. The converted problems are solved by the algorithm derived from simulated annealing to determine the optimal operating policy and the performance index. These results are useful in assessing design and operation of batch reactors. In this article, the CSTR model is used to demonstrate the convenience and robustness of the proposed algorithm. Two typical reaction models are used to discuss the operations based on the optimal solutions. 相似文献
996.
Deep Sequencing Analysis of miRNA Expression in Breast Muscle of Fast-Growing and Slow-Growing Broilers 总被引:1,自引:0,他引:1
Hongjia Ouyang Xiaomei He Guihuan Li Haiping Xu Xinzheng Jia Qinghua Nie Xiquan Zhang 《International journal of molecular sciences》2015,16(7):16242-16262
Growth performance is an important economic trait in chicken. MicroRNAs (miRNAs) have been shown to play important roles in various biological processes, but their functions in chicken growth are not yet clear. To investigate the function of miRNAs in chicken growth, breast muscle tissues of the two-tail samples (highest and lowest body weight) from Recessive White Rock (WRR) and Xinghua Chickens (XH) were performed on high throughput small RNA deep sequencing. In this study, a total of 921 miRNAs were identified, including 733 known mature miRNAs and 188 novel miRNAs. There were 200, 279, 257 and 297 differentially expressed miRNAs in the comparisons of WRRh vs. WRRl, WRRh vs. XHh, WRRl vs. XHl, and XHh vs. XHl group, respectively. A total of 22 highly differentially expressed miRNAs (fold change > 2 or < 0.5; p-value < 0.05; q-value < 0.01), which also have abundant expression (read counts > 1000) were found in our comparisons. As far as two analyses (WRRh vs. WRRl, and XHh vs. XHl) are concerned, we found 80 common differentially expressed miRNAs, while 110 miRNAs were found in WRRh vs. XHh and WRRl vs. XHl. Furthermore, 26 common miRNAs were identified among all four comparisons. Four differentially expressed miRNAs (miR-223, miR-16, miR-205a and miR-222b-5p) were validated by quantitative real-time RT-PCR (qRT-PCR). Regulatory networks of interactions among miRNAs and their targets were constructed using integrative miRNA target-prediction and network-analysis. Growth hormone receptor (GHR) was confirmed as a target of miR-146b-3p by dual-luciferase assay and qPCR, indicating that miR-34c, miR-223, miR-146b-3p, miR-21 and miR-205a are key growth-related target genes in the network. These miRNAs are proposed as candidate miRNAs for future studies concerning miRNA-target function on regulation of chicken growth. 相似文献
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Effect of dielectric packing materials on the decomposition of carbon dioxide using DBD microplasma reactor
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Xiaofei Duan Zongyuan Hu Yanping Li Baowei Wang 《American Institute of Chemical Engineers》2015,61(3):898-903
Carbon dioxide (CO2) decomposition was performed at a normal atmosphere and room temperature in dielectric barrier discharge microplasma reactors to reduce CO2 emissions and convert CO2 into valuable chemical materials. The outlet gases, including CO2, CO, and O2, were analyzed with gas chromatography. The results indicated that the conversions of CO2 in dielectric material‐packed reactors were all higher than that in nonpacked reactors. Particle size, dielectric constant, particle morphology, and acid‐base properties of the dielectric materials (including quartz wool, quartz sand, γ‐Al2O3, MgO, and CaO) all affected the CO2 decomposition process. The conversion of CO2 and energy efficiency achieved the highest values of 41.9 and 7.1% in a CaO‐packed reactor for the higher dielectric constant and basicity of CaO. Quartz wool was also an excellent dielectric packing material because its fiber structure provided rigid sharp edges. © 2014 American Institute of Chemical Engineers AIChE J, 61: 898–903, 2015 相似文献
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Zhengbing Yan Bi‐Ling Huang Yuan Yao 《American Institute of Chemical Engineers》2015,61(11):3719-3727
In batch processes, multivariate statistical process monitoring (MSPM) plays an important role for ensuring process safety. However, despite many methods proposed, few of them can be applied to batch‐to‐batch startups. The reason is that, during the startup stage, process data are usually nonstationary and nonidentically distributed from batch to batch. In this article, the trajectory signal of each process variable is decomposed into a series of components corresponding to different frequencies, by adopting a nonparametric signal decomposition technique named ensemble empirical mode decomposition. Then, through instantaneous frequency calculation, these components can be divided into two groups. The first group reflects the long‐term trend between batches, which extracts the batch‐wise nonstationary drift information. The second group corresponds to the short‐term intrabatch variations. The variable trajectory signals reconstructed from the latter fulfills the requirements of conventional MSPM. The feasibility of the proposed method is illustrated using an injection molding process. © 2015 American Institute of Chemical Engineers AIChE J, 61: 3719–3727, 2015 相似文献
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