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Wu J.-J.,Sun Yat Sen University | Cao M.-L.,CAS Guangzhou Institute of Chemistry | Ye B.-H.,Sun Yat Sen University
Chemical Communications | Year: 2010

Six possible isomers of mer-[MII(N,N,O-L)2] complex were observed in the solid state, in which spontaneous resolution of S,S-Λ and R,R-Δ enantiomers of mer-[Co(N,N,O-L3)2] was achieved via π-π interactions. © 2010 The Royal Society of Chemistry.


Huang Z.,Northeast Forestry University | Liu S.,Northeast Forestry University | Zhang B.,Northeast Forestry University | Xu L.,CAS Guangzhou Institute of Chemistry | Hu X.,Northeast Forestry University
Carbohydrate Polymers | Year: 2012

A novel β-cyclodextrin-based adsorbent (CDAA) for the removal of Cu 2+ was prepared and characterized. The adsorption capacities of Cu 2+ on CDAA were evaluated under various treatment conditions, including the solution pH, the dosage of the adsorbent, the initial Cu 2+ concentration, and adsorption time. The results indicated that CDAA hydrogel exhibited typically three-dimensional cross-link network structure. There was a significant increase in the adsorption capacity (from 18.93 mg/g to 107.37 mg/g) when the solution pH increased from 2 to 5. The adsorption equilibrium data were fitted and analyzed with Langmuir, Freundlich, Temkin isotherm equations and four adsorption kinetic models. The results suggested that the Freundlich equation model was the best fit with experimental data (R 2 = 0.995). The kinetic equations showed that the adsorption of Cu 2+ on the adsorbent fit different equations for different concentrations of Cu 2+. These results indicate that in the present study, Cu 2+ adsorption onto the adsorbent occurred via ion exchange and chemical interaction mechanisms. © 2012 Elsevier Ltd. All rights reserved.


Liu W.-J.,Hefei University of Technology | Zeng F.-X.,Hefei University of Technology | Zeng F.-X.,CAS Guangzhou Institute of Chemistry | Jiang H.,Hefei University of Technology | Zhang X.-S.,Hefei University of Technology
Bioresource Technology | Year: 2011

Bio-chars with high adsorption capacity derived from rice-husks and corncobs were prepared at different retention times (RTs) in a pyrolysis reactor. At a fixed pyrolysis temperature, the pyrolysis RT is a key factor influencing the surface areas and functional group contents of the bio-chars, and further influencing their adsorption capacities. The results indicate that the bio-char prepared at RT of 1.6s exhibits a higher phenol adsorption capacity (589mgg -1) than other bio-chars and many activated carbons reported in the literature. An adsorption mechanism based on acid-base interaction and hydrogen binding between phenol and the functional groups was proposed to elucidate the adsorption process. An economic evaluation of the use of bio-chars as adsorbents was made. © 2011 Elsevier Ltd.


Huang Y.,CAS Guangzhou Institute of Chemistry | Liu W.,CAS Guangzhou Institute of Chemistry
Journal of Sol-Gel Science and Technology | Year: 2010

New composite coatings were prepared by mixing pre-hydrolyzed methyltriethoxysilane (MTES) sol by an acidic catalyst dibutyltin dilaurate (DBTDL) and polymethylhydrosiloxane (PMHS) in gasoline at room temperature. The gel process was thoroughly investigated regarding the use of different basic catalyst [3-aminopropyltriethoxysilane (APTES) or triethylamine (TEA)], as well as the ratios of pre-hydrolyzed MTES sol and PMHS with various content of active H. It was revealed that the composite coating from 2:1 ratio (w/w) of pre-hydrolyzed MTES sol with equimolar amounts of water and PMHS1.55 under the catalysis of APTES demonstrated high pencil hardness, and excellent resistance against contamination and corrosion. This composite coating (MTPM21-A) was further characterized by FTIR, 29Si NMR, DSC and TGA. © 2010 Springer Science+Business Media, LLC.


Wu K.,CAS Guangzhou Institute of Chemistry | Shen M.-M.,CAS Guangzhou Institute of Chemistry | Hu Y.,Anhui University of Science and Technology
Journal of Polymer Research | Year: 2011

Microencapsulated ammonium polyphosphate (GMFAPP) is prepared by in situ polymerization method with a shell of poly(ethylene glycol) modified melamineformaldehyde resin. Due to the presence of shell, GMFAPP shows less size, higher water resistance and flame retardancy in polypropylene (PP) compared with ammonium polyphosphate (APP). The flame retardant action of GMFAPP and APP in PP are studied using LOI, UL-94 and cone calorimeter, and their thermal stability is evaluated by thermogravimetric apparatus. The limiting oxygen index (LOI) value of the PP/GMFAPP at the same loading is higher than the value of PP/APP. UL-94 ratings of PP/GMFAPP can reach V-0 at 30 wt% loading. The water resistant properties of the PP composites are studied, and the results of the composites containing with APP and GMFAPP are compared. The cone results put forward that GMFAPP is an effective flame retardant in PP compared with APP. Moreover, the thermal oxidative behavior of GMFAPP is evaluated by dynamic FTIR to study its flame retardant mechanism in PP. © Springer Science+Business Media B.V. 2010.


Deng L.,Anhui University of Science and Technology | Zhao Y.,Anhui University of Science and Technology | Li J.,Anhui University of Science and Technology | Fu Y.,Anhui University of Science and Technology | And 2 more authors.
ChemSusChem | Year: 2010

LA Lacers: The conversion of levulinic acid (LA) to γ-valerolactone is catalyzed by heterogeneous catalysts without using the external H2. Ru-P/SiO2 has been demonstrated to be a bifunctional catalyst giving a yield of 96 %. Through a two-step process, excellent performance can be achieved in eight recycling runs. Moreover, no hazardous 2-Me-THF is produced during the process. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Sui X.-W.,Anhui University of Science and Technology | Wang Z.,Anhui University of Science and Technology | Liao B.,CAS Guangzhou Institute of Chemistry | Zhang Y.,Anhui University of Science and Technology | Guo Q.-X.,Anhui University of Science and Technology
Bioresource Technology | Year: 2012

Fast pyrolysis of bagasse pretreated by sulfuric acid was conducted in a fixed bed reactor to prepare levoglucosenone (LGO), a very important anhydrosugar for organic synthesis. The liquid yield and LGO yield were studied at temperatures from 240 to 350. °C and sulfuric acid loadings from 0.92 to 7.10. wt.%. An optimal LGO yield of 7.58. wt.% was obtained at 270. °C with a sulfuric acid pretreatment concentration of 0.05. M (corresponding to 4.28. wt.% sulfuric acid loading). For comparison, microcrystalline cellulose pretreated by 0.05. M sulfuric acid solution was pyrolyzed at temperature from 270. °C to 320. °C, and bagasse loaded with 3-5. wt.% phosphoric acid was pyrolyzed at temperature from 270. °C to 350. °C. The highest yield of LGO from bagasse was 30% higher than that from microcrystalline cellulose, and treatment with sulfuric acid allowed a 21% higher yield than treatment with phosphoric acid. © 2011 Elsevier Ltd.


Wu K.,CAS Guangzhou Institute of Chemistry | Zhang Y.,CAS Guangzhou Institute of Chemistry | Hu W.,CAS Guangzhou Institute of Chemistry | Lian J.,CAS Guangzhou Institute of Chemistry | Hu Y.,Anhui University of Science and Technology
Composites Science and Technology | Year: 2013

Microencapsulated ammonium polyphosphate (EPAPP) with shell of epoxy resin (EP) is prepared by in situ polymerization. EP is hydrophobic, so EPAPP has better water resistance and compatibility in polypropylene (PP) composite compared with ammonium polyphosphate (APP). Due to the reaction between APP and EP under heating, EPAPP can form a residue char with good thermal stability which prevents underlying materials from further destruction during a fire. Because of the interaction and alignment of the PP polymer chains at the surface of additives, microencapsulation affects the crystal structure and spherulitic morphology of PP composite remarkably. PP/EPAPP did not show characteristic peaks for β-form crystal, while APP could act as an effective β-nucleating agent in PP. © 2013 Elsevier Ltd.


Sun Y.,CAS Guangzhou Institute of Chemistry | Sun Y.,University of Chinese Academy of Sciences | Liu W.,CAS Guangzhou Institute of Chemistry
Journal of Fluorine Chemistry | Year: 2011

A new fluorinated macroinitiator of poly 2,2,3,4,4,4-hexafluorobutyl methacrylate-Br (PHFMA-Br) was prepared via activator generated by electron transfer atom transfer radical polymerization (AGET ATRP), and then a series of fluorinated block copolymers with different fluorine content were successfully synthesized from the macroinitiator by the second step AGET ATRP. GPC, FTIR and 1H NMR data obtained verified the synthesis. Contact angle measurement indicated that proper fluorine content could decrease the surface energy and increase the contact angle of the copolymer films. XPS characterization showed that the large difference in surface energy between the block and random copolymer film resulted from the difference of the fluorine content on the surface, although the fluorine content of the two copolymers in bulk was similar. The self-assembly behavior of the fluorinated block copolymer in selective solvents was evaluated by the TEM study, and the stable micelles with a core-shell structure were observed when the copolymer content was about 1 wt%. © 2010 Elsevier B.V. All rights reserved.


Lai D.-M.,Anhui University of Science and Technology | Deng L.,Anhui University of Science and Technology | Li J.,Anhui University of Science and Technology | Liao B.,CAS Guangzhou Institute of Chemistry | And 2 more authors.
ChemSusChem | Year: 2011

The main attraction: A magnetic solid acid with mesoporous structure was synthesized for the hydrolysis cellulose into glucose. Glucose is generated efficiently from amorphous cellulose in the mesopores of the catalyst with a yield of 50 %. Moreover, catalyst separation can be readily achieved by magnetic force. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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