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synthetic process of Bio-Based Phenol Formaldehyde Adhesive Derived from Demethylated Wheat Straw Alkali Lignin and Its Curing Behavior

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Journal of Renewable Materials 2021年第5期9卷 943-957页

作者： Yan Song Zhixin Wang Xin Zhang Rong Zhang Jinchun Li Faculty of Materials Science&Engineering Changzhou UniversityChangzhou213164China Jiangsu Key Laboratory of Environmentally Friendly Polymeric Materials School of Materials Science and EngineeringChangzhou UniversityChangzhou213164China Organization Department of the Party Committee Changshu Institute of TechnologyChangshu215500China School of Petrochemical Engineering Changzhou UniversityChangzhou213164China

Lignin is a natural biopolymer with a complex three-dimensional network, commercially obtained from wasteliquid of paper pulp and bioethanol production, and could be a candidate for preparation of environment-friendlybio-based polyphenol material. In the present work, the demethylated wheat straw alkali lignin (D-Lig), preparedby demethylation of wheat straw alkali lignin (Lig) using an in-situ generated Lewis acid, was used to synthesizebio-based phenol formaldehyde resin adhesive (D-LPF) applied in plywood. Effects of synthetic process’s factors,including lignin substitution for phenol, NaOH concentration and molar ratio of formaldehyde to phenol, on thebonding strength and free formaldehyde content of D-LPF were investigated in detail, and the optimum syntheticprocess of D-LPF was obtained as following: Lignin substitution for phenol 60%, NaOH concentration 5.0% andmolar ratio of formaldehyde to phenol 2.0, and under the optimum reaction condition, the D-LPF presented lower free formaldehyde content (0.18%) and higher bonding strength (2.19 MPa), which was better than those ofcontaining-lignin phenol formaldehyde resin adhesive (LPF). Additionally, the curing behavior of the adhesivewas studied by differential scanning calorimetry (DSC) combined with gel time. It can be obtained that D-LPFresin adhesive had the shortest gel time, and fastest curing rate, compared with those of PF and L-PF resin adhesives. The curing kinetics data was fitted well by Kissinger model using non-isothermal DSC method, and theaverage activation energy value was 85.3 kJ/mol, slightly higher than that of commercial PF resin, while lowerthan that of LPF (90.2 kJ/mol). Finally, based on the analytical results of high temperature fourier transform infrared spectroscopy (FTIR), a possible curing mechanism of D-LPF was proposed.

关键词： Lignin demethylation phenol-formaldehyde resin biobased adhesive synthetic process curing behavior

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Carbon-coated lithium titanate: effect of carbon precursor addition processes on the electrochemical performance

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Frontiers of Chemical Science and Engineering 2021年第1期15卷 148-155页

作者： Shilei Ding Zelong Jiang Jing Gu Hongliang Zhang Jiajia Cai Dongdong Wang School of Energy and Environment Anhui University of TechnologyMaanshan 243002China School of Chemistry and Chemical Engineering Anhui University of TechnologyMaanshan 243002China Analysis and Testing Central Facility Anhui University of TechnologyMaanshan 243002China

In this paper,two carbon-coated lithium titanate(LTO-C1 and LTO-C2)composites were synthesized using the ball-milling-assisted calcination method with different carbon precursor addition *** physical and electrochemical properties of the as-synthesized negative electrode materials were characterized to investigate the effects of two carbon-coated LTO synthesis processes on the electrochemical performance of *** results show that the LTO-C2 synthesized by using Li2CO3 and TiO2 as the raw materials and sucrose as the carbon source in a one-pot method has less polarization during lithium insertion and extraction,minimal charge transfer impedance value and the best electrochemical performance among all *** the current density of 300 mA·h·g^(-1),the LTO-C2 composite delivers a charge capacity of 126.9 mA·h·g^(-1),and the reversible capacity after 300 cycles exceeds 121.3 mA·h·g^(-1) in the voltage range of 1.0–3.0 ***,the electrochemical impedance spectra show that LTO-C2 has higher electronic conductivity and lithium diffusion coefficient,which indicates the advantages in electrode kinetics over LTO and *** results clarify the best electrochemical properties of the carbon-coated LTO-C2 composite prepared by the one-pot method.

关键词： lithium titanate carbon-coated carbon precursor synthetic process

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Comparative process for the Preparation of 9-Oxime Erythromycin A

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Journal of Beijing Institute of Technology 2004年第1期13卷 76-79页

作者：孙京国姚国伟欧育湘 School of Material Science and Engineering Beijing Institute of Technology Beijing100081 China School of Life Science and Technology Beijing Institute of Technology Beijing100081 China . College of Chemistry Hebei Normal University Shijiazhuang Hebei050091 China

The comparative process for preparing 9-oxime erythromycin A (EMAO) is investigated. EMAO was synthesized and compared by the reaction of erythromycin and hydroxylamine hydrochloride with various bases such as sodium acetate, triethylamine, etc. A new synthetic method is established. The oximation is performed under dynamic buffer system; less degradation impurities are formed. The yield of EMAO reaches more than 95%, HPLC analysis shows that the purity of EMAO is more than 90%, and the E/Z isomeric ratio preponderates over 7∶1.

关键词： oxime erythromycin A synthetic process comparison

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Facile synthesis of fluticasone propionate derivatives and their application in anti-cancers

Facile synthesis of fluticasone propionate derivatives and t...

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第十一届全国化学生物学学术会议

作者： Quanming Zhou Menghua Xiang Chuanchao Luo Jianuo Li Zihan Shi Shaoyun Li Liuxing Xie Wei Wang Fen Yang Qicai Xiao Liqian Gao School of Pharmaceutical Sciences（Shenzhen） Sun Yat-Sen University

Fluticasone propionate, a new type of glucocorticoid developed by Glaxosmithkline in the United Kingdom, has strong efficacy and weak adverse reactions compared with other glucocorticoid drugs. We improved the synthesis of fluticasone propionate and studied its anticancer activity. First step in the synthesis of sodium periodate oxidation, silicone product load, the method of green environmental protection, economic efficiency, overall synthetic process is divided into seven steps, and of reactants, reaction is simple, from starting material fry at the end of the product, the overall yield of 90%, at the same time, in view of the fluticasone propionate functional group modification and optimization design of structure, through the study of the methylation of thiol, hydroxylation, selective oxidation of hydroxyl groups, the structure of modified research of anticancer activity, seen from the results, thiol methylation can effectively enhance its anticancer activity,A549,Hep G2, McF-7 and other cancer cells all showed good anticancer effect.

关键词： Fluticasone propionate synthetic process antitumor activity

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