This paper reports a practical and green method for the acetalization of carbonyl compounds as pentaerythritol diacetals and diketals derivatives using cellulose sulfuric acid as a biodegradable and reusable solid aci...This paper reports a practical and green method for the acetalization of carbonyl compounds as pentaerythritol diacetals and diketals derivatives using cellulose sulfuric acid as a biodegradable and reusable solid acid catalyst under thermal solvent-free conditions.展开更多
Magnesium-ferrum layered double hydroxide （Mg-Fe-LDH） and zinic-aluminum layered double hydroxide （Zn-A1-LDH） compounds were prepared through a mechanochemical method. The influence of molar ratio of M2＋ to M3＋ ...Magnesium-ferrum layered double hydroxide （Mg-Fe-LDH） and zinic-aluminum layered double hydroxide （Zn-A1-LDH） compounds were prepared through a mechanochemical method. The influence of molar ratio of M2＋ to M3＋ （R value） on the property ofLDH nanoparticles has been studied and the results showed that R=3 ： 1 is the optimum value for the both samples. Besides pure water, the mixture of water and ethanol with the volume ratio of 3 ; 1 is also used to wash the precipitates and used as suspending agent during the peptization process and our results showed that the addition of ethanol can improve the monodispersity of LDH nanoparticles greatly.展开更多
Exploring a simple,rapid,solvent-free synthetic method for mass production of cheap,broadband mi-crowave absorbers remains the main challenge.Here,a mild solvent-free procedure is reported to syn-thesize zinc oxide na...Exploring a simple,rapid,solvent-free synthetic method for mass production of cheap,broadband mi-crowave absorbers remains the main challenge.Here,a mild solvent-free procedure is reported to syn-thesize zinc oxide nanoparticles(ZnO NPs)embedded in porous carbon derived from mixing sucrose and zinc nitrate hexahydrate.The characteristic morphology and the ZnO NPs distribution in these compos-ites were tuned using the different raw materials proportions.The mesoporous structure of porous car-bon benefits the compositional advantages between carbon foam and ZnO NPs.The optimal synthesized ZnO/C-2 carbon material demonstrates the strongest absorption of-41.7 dB with a frequency of 14.5 GHz at a thin thickness of 2 mm,and its widest effective absorption is close to 6 GHz(12.2-17.8 GHz).This work produces a feasible route for the sensible design of other effective microwave absorbers for large-scale production.展开更多
文摘This paper reports a practical and green method for the acetalization of carbonyl compounds as pentaerythritol diacetals and diketals derivatives using cellulose sulfuric acid as a biodegradable and reusable solid acid catalyst under thermal solvent-free conditions.
基金This work was supported by National Natural Science Foundation of China （No. 21073093） and Doctoral Fund of Ministry of Education of China （No. 20103207120006） and Priority Academic Program Development of Jiangsu Higher Education Institutions.
文摘Magnesium-ferrum layered double hydroxide （Mg-Fe-LDH） and zinic-aluminum layered double hydroxide （Zn-A1-LDH） compounds were prepared through a mechanochemical method. The influence of molar ratio of M2＋ to M3＋ （R value） on the property ofLDH nanoparticles has been studied and the results showed that R=3 ： 1 is the optimum value for the both samples. Besides pure water, the mixture of water and ethanol with the volume ratio of 3 ; 1 is also used to wash the precipitates and used as suspending agent during the peptization process and our results showed that the addition of ethanol can improve the monodispersity of LDH nanoparticles greatly.
基金the State Key Lab of Advanced Technology for Materials Synthesis and Processing(Wuhan Univer-sity of Technology)for financial support.
文摘Exploring a simple,rapid,solvent-free synthetic method for mass production of cheap,broadband mi-crowave absorbers remains the main challenge.Here,a mild solvent-free procedure is reported to syn-thesize zinc oxide nanoparticles(ZnO NPs)embedded in porous carbon derived from mixing sucrose and zinc nitrate hexahydrate.The characteristic morphology and the ZnO NPs distribution in these compos-ites were tuned using the different raw materials proportions.The mesoporous structure of porous car-bon benefits the compositional advantages between carbon foam and ZnO NPs.The optimal synthesized ZnO/C-2 carbon material demonstrates the strongest absorption of-41.7 dB with a frequency of 14.5 GHz at a thin thickness of 2 mm,and its widest effective absorption is close to 6 GHz(12.2-17.8 GHz).This work produces a feasible route for the sensible design of other effective microwave absorbers for large-scale production.
