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101.
Xiao-Ya Shangguan Bao-Lun Fang Chen-Xiao Xu Yuan Tan Yan-Gang Chen Zhi-Jun Xia Wei Chen 《Ceramics International》2021,47(5):6318-6328
A series of direct Z-scheme FeIn2S4/Bi2WO6 hierarchical heterostructures with intimate interface contacts were synthesized by in-situ growth route and characterized by systematical analyses. All as-prepared FeIn2S4/Bi2WO6 nanocomposites showed significantly enhanced photocatalytic activity towards photodegradation for the removal of tetracycline hydrochloride (TCH) in comparison with individual FeIn2S4 and Bi2WO6. Meanwhile, the highest photocatalytic degradation activity can be achieved by modulating adding amount of FeIn2S4 in FeIn2S4/Bi2WO6 nanocomposites and the optimized component ratio of FeIn2S4 to Bi2WO6 is determined to be 10 wt%. The enhanced photocatalytic activity could be ascribed to efficient separation between photogenerated holes and electrons based on the construction of direct Z-scheme system. The high photocatalytic stability of resultant 10 wt% FeIn2S4/Bi2WO6 nanocomposites was revealed through six successive recycling reactions. The main intermediate generated during TCH photodegradation was explored by HPLC-MS. Besides, the direct Z-scheme photocatalytic mechanism was confirmed by band position analysis, electron spin resonance (ESR) and active species capture experiment. 相似文献
102.
Artificial Intelligence Review - In group decision-making problems, decision makers prefer to use several linguistic terms to describe their own perception and knowledge, and give their preference... 相似文献
103.
数据中心的高能耗低能效问题正受到广泛关注与研究,但目前没有公开的数据中心内服务器能耗数据集供研究人员使用,且现有过滤式特征选择并不能满足运维人员的需求。为此,提出了一套模拟数据中心内服务器运行状态的仿真环境架构,基于该架构采集了服务器运行各类任务时的多项性能指标和能耗数据。然后将基于因果关系的特征选择应用于能耗数据集的特征分析中,构建出可解释的特征子集和能耗预测结果。实验结果表明,因果特征子集大小约为过滤式特征子集大小的1/3到1/6,并且使用因果特征子集训练的模型在75%的情况下都取得了最优预测精度。 相似文献
104.
105.
以红花菜籽油中亚油酸为原料,偏铁酸钠为催化剂,在单因素试验的基础上,选取反应温度、反应时间、催化剂用量为考察因素,以异构化产物共轭亚油酸(CLA)转化率为响应值,通过响应面分析法对异构化反应进行优化,并建立相应的回归模型,试验结果表明,红花菜籽油中亚油酸异构化为CLA的最佳工艺为:反应温度195℃、反应时间4.7 h、催化剂用量0.6 g,在此条件下得到CLA转化率为92.90%,与预测值93.92%相比,误差为1.02%.然后再通过脲素包合纯化、经2%的H2SO4-CH3OH溶液甲酯化后,用气相色谱-质谱联用仪检测CLA含量为64.27%. 相似文献
106.
Zhongyuan Fu Xinyi Ma Bing Xia Xiaoyun Hu Jun Fan Enzhou Liu 《International Journal of Hydrogen Energy》2021,46(37):19373-19384
Schottky junction and p-n heterojunction are widely employed to enhance the charge transfer during the photocatalysis process. Herein, Cu and Cu3P co-modified TiO2 nanosheet hybrid (Cu–Cu3P/TiO2) was fabricated using an in situ hydrothermal method. The ternary composite achieved the superior H2 evolution rate of 6915.7 μmol g?1 h?1 under simulated sunlight, which was higher than that of Cu/TiO2 (4643.4 μmol g?1 h?1) and Cu3P/TiO2 (6315.8 μmol g?1 h?1) and pure TiO2 (415.7 μmol g?1 h?1). The enhanced activity can be attributed to the collaboration effect of Schottky junction and p-n heterojunction among Cu/TiO2 and Cu3P/TiO2, which can harvest the visible light, reduce the recombination of charge carriers and lower the overpotential of H2 evolution, leading to a fast H2 evolution kinetics. This work develops a feasible method for the exploration of H2 evolution photocatalyst with outstanding charge separation properties. 相似文献
107.
Hongyan Liu Yuchang Qin Qing Ma Qingyu Zhao Xiaoqing Guo Lina Ma Chunlin Gou Yu Xia Ren-You Gan Junmin Zhang 《International Journal of Food Science & Technology》2021,56(6):2604-2611
In the study, lamb, feed and soil samples were collected from three regions of China in the year 2017 and 2018. The δ13C and δ15N values in lamb (defatted dry mass and lipids) and grass and the contents of nine elements in lamb, grass and soil were determined. The results indicated that except for Fe, Zn and Rb, most variables of lamb showed significant differences among two or three regions, and the contents of Fe, Sr and Cs showed significant differences between two years, and the contents of Cu and Zn showed significant differences among different muscle sections. Besides, significant correlations were found for δ13C between defatted lamb and lipid (r2 = 0.973, P < 0.05) and for the element contents between lamb and soil. Finally, four key variables δ13C, δ15N, Sr and Mo were selected through stepwise canonical discriminant analysis with the cross-validation correct classification rate of 99.1%. 相似文献
108.
老年人作为生理弱势人群的代表,具有平等享受公共物品的权利。以老年人群搭乘轨道交通中的换乘行为为研究对象,通过路径跟随、访谈、心理量研究等方法,结合国内外文献研究,剖析轨道交通换乘序列空间与老年人群生理条件和行为特点的矛盾关键,进一步提出轨道交通换乘空间设计的适老策略。 相似文献
109.
Jhe-Wei Jhuang Kan-Rong Lee Sheng-Wei Lee Baoyuan Wang Chen Xia I.Ming Hung Chung-Jen Tseng 《International Journal of Hydrogen Energy》2021,46(15):9767-9774
Low-temperature solid oxide fuel cells (LT-SOFCs) have recently gained enormous attention worldwide with a new research trend focusing on single layer fuel cells (SLFC), which have better cell performance than traditional SOFCs at low operating temperatures. In this study, a triple (e?/O2?/H+) conducting perovskite BaCo0.4Fe0.4Zr0.1Y0.1O3-δ (BCFZY) is used as the intermediate layer material for SLFC. A high current density of 994 mA/cm2 at 0.6 V and a peak power density of 610 mW/cm2 with an OCV of 1.01 V has been achieved with a cell operating temperature of 550 °C, confirming the application feasibility of BCFZY in SLFCs. Furthermore, a typical proton conductor BaZr0.8Y0.2O3-δ (BZY) is introduced into BCFZY to enhance the cell performance. By adjusting the mass ratio of the BCFZY-BZY layer, an optimal power density is obtained, achieving 703 mW/cm2 with an OCV of 1.03 V at 550 °C with an 8BCFZY:2BZY (wt%) ratio. These findings prove that the proposed BCFZY-BZY holds great promise for developing SLFCs to realize low-temperature operation. 相似文献
110.
Qian Hua Yingying Sun Yanshun Xu Pei Gao Wenshui Xia 《International Journal of Food Science & Technology》2021,56(12):6752-6764
The microbial dynamics, diversity and succession characterisation during the fermentation of fish-chili paste, with and without starter cultures by high-throughput sequencing, were investigated to identify the relationship between microbial composition and the accumulation of biogenic amines. Results showed that Firmicutes was the predominant phylum, and Lactobacillus and Weissella were the main genera during fermentation process, regardless of the inclusion of starter cultures. Compared with naturally fermented samples (NS; no starter cultures), Pediococcus and Staphylococcus flourished in samples inoculated with SBM-52 starter culture (Staphylococcus xylosus + Staphylococcus carnosus + Pediococcus pentosaceus + Pediococcus acidilactici). Staphylococcus also accounted for a larger proportion in samples inoculated with WBX-43 starter culture (Staphylococcus xylosus + Staphylococcus carnosus). Furthermore, Enterobacter was inhibited in inoculated samples. Unweighted pair-group method with arithmetic means and principal component analyses revealed that microbiota structures were different among NS, SBM and WBX samples. In case of biogenic amines, the concentration of putrescine, cadaverine and tyramine increased to higher levels in NS samples compared with inoculated samples. Our work also investigated the relationship between core bacterial communities and biogenic amines. This study provided an improved understanding for the effects of starter cultures on the microbial community and the quality of fish-chili paste. 相似文献