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101.
Zhongbo Guan Yayan Wang Xiuxin Yu Yuanhui Shen Dongrong He Zhongli Tang Wenbin Li Donghui Zhang 《International Journal of Hydrogen Energy》2021,46(1):683-696
A dual-reflux pressure swing adsorption (DR-PSA) process was proposed and simulated to initially separate the blue coal gas, aiming to capture carbon dioxide (CO2) and enrich hydrogen (H2), simultaneously. With a feed flow rate of 7.290 slpm, a light product reflux flow rate of 0.505 slpm and the heavy product reflux flow rate of 3.68 slpm, the developed DR-PSA process could capture CO2 up to 64.01% with a recovery of 99.60% and enrich H2 up to 34.66% with a recovery of 97.63% from the blue coal gas (36.2% N2/28.5% H2/13.9% CO/12.7% CO2/8.7% CH4). In addition, in order to optimize the process, the effects of various operating parameters on the DR-PSA process performance in terms of product purity and recovery were discussed in detail, including the feed position, the light product reflux ratio and the heavy product reflux ratio. Moreover, the dynamic distribution behaviors of pressure, temperature and gas-solid concentration were presented to explain and evaluate the process separation performance in depth under different operating conditions. 相似文献
102.
Y. Song F. Li A.J. Fischer-Tlustos A.L.A. Neves Z. He M.A. Steele L.L. Guan 《Journal of dairy science》2021,104(8):8783-8797
The aim of this study was to explore the effect of colostrum feeding time on the ileal microbiome of neonatal calves. In this study, 22 male Holstein calves were randomly assigned to different colostrum feeding time treatments: after birth (at 45 min, n = 7); at 6 h after birth (n = 8); and at 12 h after birth (TRT12h; n = 7). At 51 h after birth, calves were killed and ileum digesta was collected for microbiome analysis using shotgun metagenomic sequencing. Bacteria, archaea, eukaryotes, and viruses were identified from the ileum microbiome. For the bacteriome, Firmicutes and Proteobacteria were the predominant phyla, and Escherichia, Streptococcus, Lactobacillus were the 3 most abundant genera. For the archaeal community, Euryarchaeota and Crenarchaeota were the 2 major phyla, and Methanosarcina, Methanobrevibacter, and Methanocorpusculum were the 3 most abundant genera. In total, 116 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were identified from the ileal microbiome, with “biosynthesis of vancomycin group antibiotics,” “biosynthesis of ansamycins,” “valine, leucine, and isoleucine biosynthesis,” “ribosome,” and “d-alanine metabolism” as the top 5 functions. When the ileal microbiomes were compared among the 3 treatments, the relative abundance of Enterococcus was higher in TRT12h calves, suggesting that calves may have a higher abundance of opportunistic pathogens when the feeding of colostrum is delayed for 12 h. Moreover, among all KEGG pathways, the enriched “taurine and hypotaurine metabolism” (KO00430) pathway was identified in the ileal microbiome of TRT12h calves; however, future studies are needed to understand the effect on the host. Additionally, 2 distinct ileal microbial profiles were identified across all samples, indicating that that host factors may play a significant role in driving varied microbiome changes in response to colostrum feeding time. Whether such microbiome shifts affect long-term gut function and calf performance warrants future studies. 相似文献
103.
Xiao Yihua Tang Ziqiang Hong Xiangfu 《Journal of Mechanical Science and Technology》2021,35(12):5425-5434
Journal of Mechanical Science and Technology - Laminated and segmented ceramic/polyurea composite plates were fabricated by coating bulk ceramic plate and bonding ceramic tablets with polyurea,... 相似文献
104.
Fang Liu Pengfen Hou Hui Zhang Qingjuan Tang Changhu Xue Robert W. Li 《Comprehensive Reviews in Food Science and Food Safety》2021,20(4):3918-3936
Food additives, often used to guarantee the texture, shelf-life, taste, and appearance of processed foods, have gained widespread attention due to their increased link to the growing incidence of chronic diseases. As one of the most common additives, carrageenans have been used in human diets for hundreds of years. While classified as generally recognized as safe (GRAS) for human consumption, numerous studies since the 1980s have suggested that carrageenans, particularly those with random coil conformations, may have adverse effects on gastrointestinal health, including aggravating intestinal inflammation. While these studies have provided some evidence of adverse effects, the topic is still controversial. Some have suggested that the negative consequence of the consumption of carrageenans may be structure dependent. Furthermore, pre-existing conditions may predispose individuals to varied outcomes of carrageenan intake. In this review, structure–function relationships of various carrageenans in the context of food safety are discussed. We reviewed the molecular mechanisms by which carrageenans exert their biological effects. We summarized the findings associated with carrageenan intake in animal models and clinical trials. Moreover, we examined the interactions between carrageenans and the gut microbiome in the pathogenesis of gastrointestinal disorders. This review argues for personalized guidance on carrageenan intake based on individuals’ health status. Future research efforts that aim to close the knowledge gap on the effect of low-dose and chronic carrageenan intake as well as interactions among food additives should be conducive to the improved safety profile of carrageenans in processed food products. 相似文献
105.
在传统地铁隧道施工中,有轨机车为主要运输方式,近年来有少量项目采用多功能胶轮机车运送施工材料。本文依托莫斯科地铁第三换乘环线东段大直径盾构项目案例,介绍胶轮机车的结构特点、使用优势、弧面运行时的轮胎保护措施。实践证明,胶轮机车在地铁隧道施工中具有很好的技术经济性,改进后的运行方式使其在管片弧面运行时性能更稳定。 相似文献
106.
在交通工程体系中,桥梁已经成为常见的工程项目,而桥梁工程的质量不仅与施工管理有关,与土木工程的施工质量也有直接的联系.文章在土木工程施工管理的基础上,分析其中常见的问题,并且提出对策,以期为当前土木工程的质量优化提供参考. 相似文献
107.
Neutron capture therapy with Sulfur-33, similar to boron neutron capture therapy with Boron-10, is effective in treating some types of tumors including ocular melanoma. The key point in sulfur neutron capture therapy is whether the neutron beam flux and the resonance capture cross section of ~(33)S(n;α)~(30) Si reaction at 13.5 keV can achieve the requirements of radiotherapy. In this research,the authors investigated the production of 13.5 keV neutron production and moderation based on an accelerator neutron source. A lithium glass detector was used to measure the neutron flux produced via near threshold~7 Li(p,n)~7 Be reaction using the time-of-flight method. Furthermore, the moderation effects of different kinds of materials were investigated using Monte Carlo simulation. 相似文献
108.
109.
G. L. Wang J. L. Li J. T. Xiong W. L. Wang P. Y. MA 《Journal of Adhesion Science and Technology》2019,33(10):1033-1046
In this study, evolution characteristics of the friction interface during rotary friction welding of tube were investigated. The friction interface that obtained at different welding stage were observed by confocal laser scanning microscopy. The results show that the friction interface transforms from sliding friction state to visco-plastic deformation state when the welding torque reaches the peak value. In addition, based on the thermodynamic framework extracted from the maximum entropy production principle, an analytical model for transition criterion from sliding friction to visco-plastic deformation was established. The model was verified by the corresponding experimental results of eight alloys, which indicated that the accuracy and generality of the model is satisfactory. 相似文献
110.