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2.
Liang Feng Jiandong Pang Ping She Jia-Luo Li Jun-Sheng Qin Dong-Ying Du Hong-Cai Zhou 《Advanced materials (Deerfield Beach, Fla.)》2020,32(44):2004414
Metal–organic frameworks (MOFs) based on group 3 and 4 metals are considered as the most promising MOFs for varying practical applications including water adsorption, carbon conversion, and biomedical applications. The relatively strong coordination bonds and versatile coordination modes within these MOFs endow the framework with high chemical stability, diverse structures and topologies, and interesting properties and functions. Herein, the significant progress made on this series of MOFs since 2018 is summarized and an update on the current status and future trends on the structural design of robust MOFs with high connectivity is provided. Cluster chemistry involving Y, lanthanides (Ln, from La to Lu), actinides (An, from Ac to Lr), Ti, and Zr is initially introduced. This is followed by a review of recently developed MOFs based on group 3 and 4 metals with their structures discussed based on the types of inorganic or organic building blocks. The novel properties and arising applications of these MOFs in catalysis, adsorption and separation, delivery, and sensing are highlighted. Overall, this review is expected to provide a timely summary on MOFs based on group 3 and 4 metals, which shall guide the future discovery and development of stable and functional MOFs for practical applications. 相似文献
3.
Pellicle formation,microbial succession and lactic acid utilisation during the aerobic deteriorating process of Sichuan pickle 下载免费PDF全文
Yu Rao Yang Qian Xiao She Jiantao Yang Penghui He Yunlu Jiang Meng Wang Wenliang Xiang 《International Journal of Food Science & Technology》2018,53(3):767-775
The pellicles formation, microbial changes and lactic acid utilisation during the aerobic deterioration of Sichuan pickle were discussed in this study. By plate counting, chemical detection and HPLC analysis, the aerobic deterioration of Sichuan pickle was featured by microbial growth, pellicle formation, lactic acid decrease and pH elevation. Bacteria dominated in pellicles and the pellicles present morphological change from smooth to wrinkly along with the aerobic deteriorating process. Nine species of bacteria were identified and responsible for the pellicle formation. Combined with Lactobacillus plantarum, eight pellicle‐forming bacteria were the dominant lactic acid consuming organisms in deteriorating Sichuan pickle. Especially under the harsh acid condition of the early deteriorating period, Lb. plantarum, pellicle‐forming bacteria Bacillus amyloliquefaciens, B. subtilis and Citrobacter freundii participated in the pellicles, utilised lactic acid and increased the brine pH effectively. Sequence analysis of 16S rDNA libraries suggested that the resulting pH of 4.8–5.0 initiated the growth of more undesirable organisms, and the pellicle bacterial diversity changed greatly compared with that in the early deteriorating period. The study indicated the important role of pellicles in the initiation of Sichuan pickle's aerobic deterioration and enhanced our ability to understand and potentially control the aerobic deterioration. 相似文献
4.
目的 采用响应面法优化柠檬苦素降解酶的固定工艺。方法 采用海藻酸钠-聚乙烯醇固定柠檬苦素降解酶,通过单因素和响应面实验对固定化条件进行优化,确定最佳的工艺参数。结果 优化后的工艺参数为:以聚乙烯醇(0.2 g/100 mL)-海藻酸钠(5.0 g/100 mL)为载体,戊二醛(2 mL/100 mL)为交联剂,采用包埋法固定柠檬苦素降解酶,其中粗酶液浓度0.06 mg/mL、CaCl2浓度6 mg/mL、固定化时间22 h。此条件下的柠檬苦素降解率为(97.87±0.32)%。结论 经优化后的工艺生产出的酶降解率高并且易于分离,具有很好的实际应用价值。 相似文献
5.
6.
Ke Xu Zhenyun She Hongwei Wang Xingli Liu Yanyan Zhang Chengdeng Chi Hua Zhang 《International Journal of Food Science & Technology》2021,56(8):4081-4090
Effects of germination on components and structural changes of rice flours and, in turn, rheological properties and textural attributes of sweet dumplings were investigated in this study. Germination decreased starch, protein and lipid content, while slightly increased free amino acids content. Starch granular surface corroded, crystalline structure disrupted, and short-range ordered structures and helical structures decreased with germination. Moreover, germination resulted in a decreased paste viscosity and gel intensity of flour and a reduction of hardness and adhesiveness of dumplings. According to the Pearson’s correlation analysis, flours components and starch structures were significantly correlated with flours rheological properties that determined textural attributes of sweet dumplings. The germination contributed to significant changes in flours components and starch structures, which suggested the pretreatment of germination of waxy rice could be a promising pathway to control textural properties of sweet dumplings. 相似文献
7.
正Asian Cities:Planning and Development Editors:Wu Jiang, Zhang Fan, Sha Yongjie, Xia Liping Year:2018 Publisher:Tongji University Press ISBN:9787560875774 1. Publishing background The Asian Cities:Planning and Development edited by Prof. Wu 相似文献
8.
Wei-Tao Yang Qian Yin Yang Li Gang Guo Yong-Hong Li Chao-Hui He Yan-Wen Zhang Fu-Qiang Zhang Jin-Hua Han 《核技术(英文版)》2019,30(10)
Single-event effects(SEEs) induced by medium-energy protons in a 28 nm system-on-chip(So C) were investigated at the China Institute of Atomic Energy. An on-chip memory block was irradiated with 90 MeV and70 MeV protons, respectively. Single-bit upset and multicell upset events were observed, and an uppermost number of nine upset cells were discovered in the 90 MeV proton irradiation test. The results indicate that the SEE sensitivities of the 28 nm SoC to the 90 MeV and 70 MeV protons were similar. Cosmic Ray Effects on Micro-Electronics Monte Carlo simulations were analyzed, and it demonstrates that protons can induce effects in a 28 nm SoC if their energies are greater than 1.4 MeV and that the lowest corresponding linear energy transfer was 0.142 MeV cm~2 mg~(-1). The similarities and discrepancies of the SEEs induced by the 90 MeV and 70 MeV protons were analyzed. 相似文献
9.
Yuxing Yan Guangrui Chen Peihong She Guiyuan Zhong Wenfu Yan Bu Yuan Guan Yusuke Yamauchi 《Advanced materials (Deerfield Beach, Fla.)》2020,32(44):2004654
Mesoporous materials have attracted considerable attention because of their distinctive properties, including high surface areas, large pore sizes, tunable pore structures, controllable chemical compositions, and abundant forms of composite materials. During the last decade, there has been increasing research interest in constructing advanced mesoporous nanomaterials possessing short and open channels with efficient mass diffusion capability and rich accessible active sites for electrochemical energy conversion and storage. Here, the synthesis, structures, and energy-related applications of mesoporous nanomaterials are the main focus. After a brief summary of synthetic methods of mesoporous nanostructures, the delicate design and construction of mesoporous nanomaterials are described in detail through precise tailoring of the particle sizes, pore sizes, and nanostructures. Afterward, their applications as electrode materials for lithium-ion batteries, supercapacitors, water-splitting electrolyzers, and fuel cells are discussed. Finally, the possible development directions and challenges of mesoporous nanomaterials for electrochemical energy conversion and storage are proposed. 相似文献
10.