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991.
以Al2O3-TiO2混合物为载体,采用过量浸渍法负载Pt制备出催化剂涂层,再将其涂覆到堇青石蜂窝载体上制备了整体式催化剂,利用N2吸附/脱附、XRD、NH3-TPD、SEM-EDS表征。研究了催化剂涂层中TiO2含量和Pt负载量对甲醛去除率的影响。结果表明:TiO2的含量为5wt%,Pt的负载量为1wt%的整体式催化剂在室温(5~35 ℃)、甲醛气体进口浓度为50~300 mg·m-3和体积空速为10000 h-1的条件下,甲醛去除率达98.4%以上。连续反应150 h之后催化剂仍可保持良好催化活性。
相似文献
992.
Two novel rhodamine-based polystyrene solid-phase fluorescence sensors PS-PA-I and PS-PA-II with different lengths of polyamines were synthesized for Hg(II) determination. The detection mechanism involving the Hg(II) chelation-induced spirocycle open of rhodamine was proposed with the aid of theoretical calculation. The stronger N-Hg bond and the longer polyamine chain in PS-PA-II led to a better selectivity, much higher and more quickly fluorescence response to Hg(II). 相似文献
993.
994.
Jingjuan Liu Yi Zhou Zhen Xie Yang Li Yunpeng Liu Jie Sun Yanhang Ma Osamu Terasaki Long Chen 《Angewandte Chemie (International ed. in English)》2020,59(3):1081-1086
A conjugated copper(II) catecholate based metal–organic framework (namely Cu‐DBC) was prepared using a D2‐symmetric redox‐active ligand in a copper bis(dihydroxy) coordination geometry. The π‐d conjugated framework exhibits typical semiconducting behavior with a high electrical conductivity of ca. 1.0 S m?1 at room temperature. Benefiting from the good electrical conductivity and the excellent redox reversibility of both ligand and copper centers, Cu‐DBC electrode features superior capacitor performances with gravimetric capacitance up to 479 F g?1 at a discharge rate of 0.2 A g?1. Moreover, the symmetric solid‐state supercapacitor of Cu‐DBC exhibits high areal (879 mF cm?2) and volumetric (22 F cm?3) capacitances, as well as good rate capability. These metrics are superior to most reported MOF‐based supercapacitors, demonstrating promising applications in energy‐storage devices. 相似文献
995.
Katsuhiko Ariga Xiaofang Jia Jingwen Song Jonathan P. Hill David Tai Leong Yi Jia Junbai Li 《Angewandte Chemie (International ed. in English)》2020,59(36):15424-15446
Incorporation of non‐equilibrium actions in the sequence of self‐assembly processes would be an effective means to establish bio‐like high functionality hierarchical assemblies. As a novel methodology beyond self‐assembly, nanoarchitectonics, which has as its aim the fabrication of functional materials systems from nanoscopic units through the methodological fusion of nanotechnology with other scientific disciplines including organic synthesis, supramolecular chemistry, microfabrication, and bio‐process, has been applied to this strategy. The application of non‐equilibrium factors to conventional self‐assembly processes is discussed on the basis of examples of directed assembly, Langmuir–Blodgett assembly, and layer‐by‐layer assembly. In particular, examples of the fabrication of hierarchical functional structures using bio‐active components such as proteins or by the combination of bio‐components and two‐dimensional nanomaterials, are described. Methodologies described in this review article highlight possible approaches using the nanoarchitectonics concept beyond self‐assembly for creation of bio‐like higher functionalities and hierarchical structural organization. 相似文献
996.
Qi‐Zhi Zhong Joseph J. Richardson Shiyao Li Wenjie Zhang Yi Ju Jianhua Li Shuaijun Pan Jingqu Chen Frank Caruso 《Angewandte Chemie (International ed. in English)》2020,59(4):1711-1717
Functional coatings are of considerable interest because of their fundamental implications for interfacial assembly and promise for numerous applications. Universally adherent materials have recently emerged as versatile functional coatings; however, such coatings are generally limited to catechol, (ortho‐diphenol)‐containing molecules, as building blocks. Here, we report a facile, biofriendly enzyme‐mediated strategy for assembling a wide range of molecules (e.g., 14 representative molecules in this study) that do not natively have catechol moieties, including small molecules, peptides, and proteins, on various surfaces, while preserving the molecule's inherent function, such as catalysis (≈80 % retention of enzymatic activity for trypsin). Assembly is achieved by in situ conversion of monophenols into catechols via tyrosinase, where films form on surfaces via covalent and coordination cross‐linking. The resulting coatings are robust, functional (e.g., in protective coatings, biological imaging, and enzymatic catalysis), and versatile for diverse secondary surface‐confined reactions (e.g., biomineralization, metal ion chelation, and N‐hydroxysuccinimide conjugation). 相似文献
997.
Chitosan (CS) with good hydrophilicity and charged property was used to modify graphene oxide (GO), the obtained GO‐CS was used as a novel modifier to fabricate thin film composite forward osmosis (FO) membranes. The results revealed that the amino groups on CS reacted with carboxyl groups on GO, and the lamellar structure of the GO nanosheets was peeled off by CS, resulting in the reducing of their thicknesses. The GO‐CS improved the hydrophilicity of polyethersulfone (PES) substrate, and their contact angles decreased to 64° with the addition of GO‐CS in the substrate. GO‐CS also increased the porosity of the substrate and surface roughness of FO membrane, thereby optimizing the water flux and reverse salt flux of FO membrane. The average water flux of the FO membrane reached the optimal flux of 21.34 L/(m2 h) when GO‐CS addition was 0.5 wt%, and further addition of GO‐CS to the substrate would decrease the water flux of FO membrane, and the reverse salt flux also decreased to the lowest value of 2.26 g/(m2 h). However, the salt rejection of the membrane increased from 91.4% to 95.1% when GO‐CS addition increased from 0.5 to 1.0 wt% under FO mode using 1 mol/L sodium chloride (NaCl) solution as draw solution (DS). In addition, high osmotic pressure favored water permeation, and at the same concentration of DS, magnesium chloride (MgCl2) exhibited better properties than NaCl. These results all suggested that GO‐CS was a good modifier to fabricate FO membrane, and MgCl2 was a good DS candidate. 相似文献
998.
采用乙醇浸提法来提取地锦草中的有效成分,并对其生物活性进行研究。探讨了地锦草总黄酮的最佳提取工艺;通过体外抗氧化实验,对地锦草提取物的抗氧化活性进行研究;同时考察了提取物对大肠杆菌、枯草芽孢杆菌、青霉、曲霉的抗菌性能,并对地锦草提取物对α-淀粉酶的抑制活性进行研究。实验结果表明:地锦草总黄酮最佳提取工艺为乙醇体积分数为85%,料液比为1∶15,提取次数为3次;体外抗氧化实验表明,地锦草具有抗氧化活性,且在浓度为8 mg/mL最为明显;抗菌性能实验表明,地锦草具有抗菌性能,且对青霉、曲霉的抗菌效果比较显著;α-淀粉酶的抑制活性的实验表明,地锦草提取物对α-淀粉酶的活性有抑制能力,在pH 6.8、浓度为4.8 mg/mL、温度为70℃时,其对α-淀粉酶的抑制效果达到最大。 相似文献
999.
Jiang Liang Lei Yuan Liu Qinfeng Wang Yi Zhao Yuanyang Lei Jingxin 《Journal of Thermal Analysis and Calorimetry》2020,139(1):137-146
Journal of Thermal Analysis and Calorimetry - The polyethylene glycol/wood-flour (PEG/WF) composites were synthesized as novel form-stable phase change materials (PCMs) using PEG as phase change... 相似文献
1000.
Yu Jiawen Li Xiaojun Li Yi Wang Yue 《Journal of Thermal Analysis and Calorimetry》2020,140(1):177-187
Journal of Thermal Analysis and Calorimetry - We investigated the release behaviors and reaction reactivities of gaseous products during CO2 gasification of three chars (Guanghui char, Hongshagang... 相似文献