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921.
Duo Pan Shengsong Ge Jiangyang Tian Qian Shao Lin Guo Hu Liu Shide Wu Tao Ding Zhanhu Guo 《Chemical record (New York, N.Y.)》2020,20(4):355-369
With the rapid development of industry and agriculture and the greatly improved living conditions, the resultant gradually deteriorated environments threaten the human beings. Refractory or even toxic pollutants, which are from different industries such as printing and dyeing, pesticides, chemicals, petrochemicals, plastics and rubber, seriously threat the ecosystems and human health. Having the advantages of flexible composition, unique structure, high stability, memory effect, easy preparation and low cost, hydrotalcite compounds have a great potential in sewage degradation and environmental protection. This study focuses on the adsorption and catalytic properties (such as photocatalysis, electrocatalysis and photoelectrocatalysis) of hydrotalcite‐derived materials for treating organic, inorganic and heavy metal ion sewage. The types of adsorption and catalysis, and the effects of various influencing factors on the degradation efficiency were discussed as well. 相似文献
922.
XuanLin Meng Yang Li Chongchong Lu Man Zhao Ming Li ShaoLi Wang ChangBao Zhao Bao Lin LuYue Shang Zhaohui Chu Xinhua Ding 《Journal of separation science》2020,43(12):2311-2320
In a recent study, anthocyanins, which have a strong free radical‐scavenging activity, were examined for their potential to effectively prevent cancer. However, clinical trials are limited by the purity of the anthocyanin. Multiple methods are used to extract and purify anthocyanins. Based on previous work on Solanum nigrum, which is a widely distributed plant, in this study, DM130 macroporous resin, Sephadex LH20, and a C18 column were used to separate cis–trans anthocyanin isomers. These anthocyanins constitute the majority of total S. nigrum anthocyanins. The results showed that this “DM130‐LH20‐C18 system” can be used to obtain a cinnamic acid‐derived cis–trans anthocyanin, petunidin‐3‐(p‐coumaroyl)‐rutinoside‐5‐glucoside, with a purity of 98.5%, for effective quantitation. In order to determine the antioxidant ability of the petunidin‐3‐(p‐coumaroyl)‐rutinoside‐5‐glucoside cis–trans isomers, three ordinary methods were adopted. The maximum antioxidant ability of the cis–trans anthocyanin was dozens of times higher than that of vitamin C. 相似文献
923.
924.
Glycoproteins are produced by the post‐translational modification process of proteins and they play an important role in mediating various biological processes. Our understanding towards biochemical functions of individual glycoproteins has been seriously hampered due to the heterogeneous expression of carbohydrate parts in glycoproteins. Despite the advancement in recombinant expression and chromatographic techniques, the isolation of pure glycoforms remains nearly impossible. To obtain homogenous glycoproteins, tremendous efforts hves been spent in developing various ligation and glycosylation techniques. This minireview discusses selected methods for the preparation and ligation of glycopeptides. The importance of the development of new chemical synthesis method for glycoproteins has also been discussed, which would be one of the next directions in this field. 相似文献
925.
Feng Zhanxia Chang Zongyu Deng Chao Zhao Lin Chen Jia Zhang Jiakun Zheng Zhongqiang 《Nonlinear dynamics》2022,108(3):2007-2022
Nonlinear Dynamics - Wave glider is an unmanned surface vehicle that can directly convert wave energy into forward propulsion and fulfill long-term marine monitoring. A previous study suggested... 相似文献
926.
Nonlinear Dynamics - A time-delayed proportional–derivative controller is applied to suppress the nonlinear vibration of a rigid rotor suspended by the active magnetic bearing (AMB) subjected... 相似文献
927.
Shyue-Tzoo Lin Steve K. Huang 《Journal of polymer science. Part A, Polymer chemistry》1996,34(5):869-884
Siloxane-modified sulfone-containing epoxy resins (ESBS) were prepared by polycondensation of PMPS and/or PDMS siloxane oligomers with EBS, the sulfone-containing epoxy resin. Structures were analyzed by IR, 1H-, and 13C-NMR. The siloxane content in the copolymers was determined by 1H-NMR with an integration technique. Epoxy equivalent weight (EEW) determination indicated that the oxirane ring of EBS was intact with this hot-melt procedure. The GPC measurement of these ESBS copolymers showed that molecular weight (MW) increased with increasing siloxane content in PMPS-modified copolymers. Evidence of siloxane incorporation in the copolymer was discussed. © 1996 John Wiley & Sons, Inc. 相似文献
928.
Y. Lin H. Yasuda M. Miyama T. Yasuda 《Journal of polymer science. Part A, Polymer chemistry》1996,34(10):1843-1851
Perfluorocarbon monomers such as C2F4, C2F6, C4F10, and mixtures thereof with H2, were subjected to plasma polymerization and deposited onto low-density polyethylene (LDPE) substrates. The effect of plasma conditions, surface characteristics, and surface dynamics of plasma polymers on their ability to improve the resistance to water vapor permeation was investigated. An optimum discharge energy density was found for a monomer which provided the greatest reduction water vapor permeability. Although all of the plasma polymers show higher hydrophobicity than polyethylene, the reduction in water vapor permeability is not uniquely related to water contact angle. The surface-dynamic stability of a plasma polymer surface was found to be the key factor in determining the barrier performance of the plasma polymer. The extent of change of surface-configuration after water immersion strongly correlated with the improvement in the water vapor permeation resistance. Plasma polymers with the higher surface-dynamic stability provided the better water barrier coating applied on LDPE films. © 1996 John Wiley & Sons, Inc. 相似文献
929.
Yu Xing Peng Jia Lin Liu Lin Feng Cun 《Journal of polymer science. Part A, Polymer chemistry》1996,34(17):3527-3530
endo-Dicyclopentadiene (DCPD) was polymerized by various cationic initiating systems in different solvents. IR and 1H NMR results show that four types of structural units are formed due to the corresponding addition modes: the addition on the norbornenic (NB) double bond generates unit I and rearranged unit II, while the addition on the cyclopentenic (CP) double bond produces unit III and rearranged unit IV. The reaction medium has a stronger effect on the microstructure of the polymer (PDCPD) than initiating systems. The polymers prepared in toluene and n-hexane contain all four structural units, while the polymer produced in methylene chloride is composed of structural units II and IV. © 1996 John Wiley & Sons, Inc. 相似文献
930.
Fang Hua Lin 《纯数学与应用数学通讯》1996,49(4):323-359