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Frontiers of Chemical Science and Engineering 2009年第2期3卷 215-218页

作者： Hualiang AN Xinqiang ZHAO Zhiguang JIA Changcheng WU Yanji WANG Hebei Provincial Key Lab of Green Chemical Technology and High Efficient Energy Saving Hebei University of TechnologyTianjin 300130China

To facilitate the recovery of Pb/SiO_(2) catalyst,magnetic Pb/Fe_(3)O_(4)/SiO_(2) samples were prepared separately by emulsification,sol-gel and incipient impregnation *** catalyst samples were characterized by means of X-ray diffraction and N_(2) adsorption-desorption,and their catalytic activity was investigated in the reaction for synthesizing propylene carbonate from urea and 1,2-propylene *** the gelatin was applied in the preparation of Fe_(3)O_(4) at 60℃ and the pH value was controlled at 4 in the preparation of Fe_(3)O_(4)/SiO_(2),the Pb/Fe_(3)O_(4)/SiO_(2) sample shows good catalytic activity and *** the reaction conditions of a reaction temperature of 180℃,reaction time of 2h,catalyst percentage of 1.7 wt-% and a molar ratio of urea to PG of 1∶4,the yield of propylene carbonate attained was 87.7%.

关键词： Pb/Fe_(3)O_(4)/SiO_(2)magnetic particle urea 1 2-propylene glycol propylene carbonate

Collagen structure changes during chrome tanning in propylene carbonate

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Journal of Leather Science and Engineering 2019年第1期1卷 94-100页

作者： Yi Zhang Jenna Kate Buchanan Geoff Holmes Bradley William Mansel Sujay Prabakar Leather and Shoe Research Association of New Zealand P.O.Box 8094Palmerston North 4472New Zealand Chemical Engineering Building National Tsing Hua UniversityNo.101Section 2Guangfu RoadEast DistrictHsinchu City 300TaiwanRepublic of China

Green solvents,such as propylene carbonate(PC),can be used in leather processing to improve the efficiency of chrome tanning and reduce *** we report a combined small-angle X-ray scattering(SAXS)and differential scanning calorimetry(DSC)study on PC and its efficacy as a carrier medium during chrome *** analysis on the collagen structure of chrome tanned leather using PC,compared to conventionally tanned leather using water,showed an increase in Cr uptake in addition to the more uniform penetration of Cr through the leather *** increased binding of Cr to the collagen matrix drives the decreased hydration environment of the collagen triple ***,DSC studies show a uniform hydrothermal stability for the PC samples due to the more even distribution of Cr through the collagen *** the mechanisms by which chrome tanning occurs in non-aqueous solvents can guide us towards a more sustainable future for the leather industry.

关键词： propylene carbonate Collagen structure SAXS DSC Chrome tanning

Direct synthesis of propylene carbonate from propylene and carbon dioxide catalyzed by quaternary ammonium heteropolyphosphatotungstate–TBAB system

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Journal of Energy Chemistry 2015年第3期24卷 353-358页

作者： Gongda Zhao Yi Zhang Hengyun Zhang Jun Li Shuang Gao Dalian Institute of Chemical Physics Chinese Academy of SciencesDalian National Laboratory for Clean Energy State Key Laboratory of Fine Chemicals Dalian University of Technology University of Chinese Academy of Sciences

In this paper,we have developed a highly efficient method for the direct preparation of propylene carbonate from propylene and carbon dioxide（CO2） using quaternary ammonium heteropolyphosphatotungstate–quaternary ammonium halide catalytic system with anhydrous hydrogen peroxide as an oxidant through one-pot two-step *** effects of the amount of tetrabutylammonium bromide（TBAB）,the concentration of hydrogen peroxide and other reaction conditions were *** catalyst system gave an optimum propylene oxide yield（91%） at75°C in oxidation step and the highest propylene carbonate yield（99%） at 140°C and 3.0 MPa in cycloaddition *** on the results,a reaction mechanism has been proposed.

关键词： quaternary ammonium heteropolyphosphatotungstate propylene carbonate carbon dioxide tetrabutylammonium bromide

Modification of solid electrolyte interface layer between PVDF-based electrolyte and lithium anode

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Journal of Materiomics 2024年第4期10卷 880-888页

作者： Ying Liang Jie Zhang Shundong Guan Kaihua Wen Chuangjie Guo Yu-Hsien Wu Haocheng Yuan Sijie Liu Ying Qi Wenbin Mo Xue Zhang Ce-Wen Nan State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China Qingtao Institute of New Energy Materials Qingtao(Kunshan)Energy Development Co.LtdKunshanJiangsu215300China

Poly(vinylidene fluoride)(PVDF)-based polymer electrolytes(PEs)with good electrochemical performance and processability as well as low-cost advantage,have great potential applications in solid-state lithium(Li)metal batteries(SSLMBs).PVDF-based PEs are generally produced by employing a solution-casting approach with N,N-dimethylformamide(DMF)as the solvent,accompanied by the formation of[DMF-Li^(+)]complex,which facilitates the Li-ion ***,the residual DMF can react continuously with lithium(Li)metal,thereby deteriorating the interface layer in the middle of the PVDF-based PEs and Li ***,we introduce propylene carbonate(PC)into the PVDF-based PEs to regulate the solvation structure and stabilize the interface layer between the PEs and Li *** accelerates the dissociation of lithium oxalyldifluoroborate(LiODFB).Consequently,“lithium propylene dicarbonate(LPDC)‒B-O”oligomer forms as the interfacial layer with high tenacity,homogeneity,and densification,which improves the interfacial contact and suppresses the continuous reaction between the residual DMF and Li *** further demonstrate that the PVDF-based PE prepared with DMF-PC mix-solvents shows improved room-temperature ionic conductivity(1.18×10^(-3) S/cm),enhanced stability against electrodes,and superior cycling performance in LiCoO_(2)-based SSLMBs(maintaining 84% of the initial discharge capacity after 300 cycles).

关键词： Solid-state battery Lithium metal Poly(vinylidene fluoride)electrolyte propylene carbonate SEI layer

Color and Gloss Changes of a Lignin-Based Polyurethane Coating under Accelerated Weathering

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Journal of Renewable Materials 2024年第2期12卷 305-323页

作者： Fatemeh Hassani Khorshidi Saeed Kazemi Najafi Farhood Najafi Antonio Pizzi Dick Sandberg Rabi Behrooz Department of Wood Science and Technology Faculty of Natural ResourcesTarbiat Modares UniversityTehranIran Department of Resin and Additives Institute for Color Science and TechnologyP.O.Box 16765-654TehranIran LERMAB University of LorraineBlvd des AiguillettesNancy54000France Wood Science and Engineering LuleåUniversity of TechnologySkellefteåSweden

The purpose of this research study was to investigate the properties of polyurethane coatings based on lignin *** this purpose,the prepared coatings were applied to pine wood surfaces and weathered ***,color and gloss of the coatings were measured before and after the weathering *** emission scanning electron microscopy(FE-SEM)micrographs prepared from the coatings showed that the average size of nano-particles in the polyurethane substrate was approximately 500 *** magnetic resonance(13C-NMR)spectroscopy showed that strong urethane bonds were formed in the nano-lignin-based *** calorimetric analysis(DSC)test revealed that the glass-transition temperature(Tg)of lignin nanoparticles modified with diethylenetriamine(DETA)was 112.8℃ and Tg of lignin nano-particles modified with ethylenediamine(EDA)was 102.5℃,which is lower than the Tg of un-modified lignin(114.6℃)and lignin modified with DETA(126.8℃)and lignin modified with EDA(131.3℃).The coatings modified with lignin nano-particles had a greater change in *** lignin nano-particles in the modified coating are trapping hydroxyl radicals which reduces photoactivity and yellowing of the polyurethane by about 3 times compared to unmodified polyurethane *** weathering test,the nano-lignin-based coating had a rougher surface with a lower contact angle(0.78°)compared to the unmodified polyurethane coating(0.85°).

关键词： Amination propylene carbonate lignin biopolymer polyurethane coating polyol UN SDG 13

Functionalization of nitrogen-doped graphene quantum dot:A sustainable carbon-based catalyst for the production of cyclic carbonate from epoxide and CO_(2)

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Journal of Environmental Sciences 2023年第4期126卷 408-422页

作者： Zahra Eshaghi Gorji Abbas Ali Khodadadi Siavash Riahi Timo Repo Yadollah Mortazavi Marianna Kemell Catalysis and Nanostructured Materials Research Laboratory School of Chemical EngineeringCollege of EngineeringUniversity of TehranTehran ***Iran Department of Chemistry University of HelsinkiHelsinki 00014Finland Institute of Petroleum Engineering School of Chemical EngineeringCollege of EngineeringUniversity of TehranTehran ***Iran

A series of organic compounds were successfully immobilized on an N-doped graphene quantum dot (N-GQD) to prepare a multifunctional organocatalyst for coupling reaction between CO_(2)and propylene oxide (PO).The simultaneous presence of halide ions in conjunction with acidic-and basic-functional groups on the surface of the nanoparticles makes them highly active for the production of propylene carbonate (PC).The effects of variables such as catalyst loading,reaction temperature,and structure of substituents are *** proposed catalysts were characterized by different techniques,including Fourier transform infrared spectroscopy (FTIR),field emission scanning electron microscopy/energy dispersive X-ray microanalysis (FESEM/EDX),thermogravimetric analysis (TGA),elemental analysis,atomic force microscopy (AFM),and ultraviolet–visible (UV-Vis) *** optimal reaction conditions,3-bromopropionic acid (BPA) immobilized on N-GQD showed a remarkable activity,affording the highest yield of 98%at 140℃ and 106Pa without any co-catalyst or *** new metal-free catalysts have the advantage of easy separation and reuse several *** on the experimental data,a plausible reaction mechanism is suggested,where the hydrogen bonding donors and halogen ion can activate the epoxide,and amine functional groups play a vital role in CO_(2)adsorption.

关键词： Heterogeneous organocatalyst CO_(2) propylene carbonate N-doped graphene quantum dot Nanomaterials

Outstanding performances of graphite||NMC622 pouch cells enabled by a non-inert diluent

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能源化学:英文版 2023年第6期81卷 593-602,I0013页

作者： Qinqin Cai Hao Jia Guanjie Li Zhangyating Xie Xintao Zhou Zekai Ma Lidan Xing Weishan Li Engineering Research Center of MTEES(Ministry of Education) Research Center of BMET(Guangdong Province)Engineering Lab.of OFMHEB(Guangdong Province)Key Lab.of ETESPG(GHEI)and Innovative Platform for ITBMD(Guangzhou Municipality)School of ChemistrySouth China Normal UniversityGuangzhou 510006GuangdongChina

Although high salt concentration electrolyte(HCE)can construct effective Li F-rich interphase film and solve the interphasial instability issue of graphite anode,its high cost,high viscosity and poor wettability with electrode materials limit its large-scale ***,localized high concentration electrolyte(LHCE)is obtained by introducing an electrochemically inert diluent into HCE to avoid the above-mentioned problems while maintaining the high interphasial stability of HCE with graphite *** traditional inert diluents,1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluropropyl ether(TTE)with electrochemical activity is introduced into propylene carbonate(PC)-based HCE to obtain LHCE-2(1 M LiPF_(6),PC:DMC:TTE=1:1:6.1)*** and theoretical simulation results show that TTE participates in the oxidation decomposition and film-forming reaction at the NCM622 cathode surface,conducting a cathode electrolyte interphase(CEI)rich in organic fluorides with excellent electron insulation ability,high structural stability and low interphasial *** to the outstanding interphasial properties induced by LHCE-2,the graphite||NMC622 pouch cell reaches a capacity retention of 80%after 500 cycles at 1 C under room *** at sub-zero temperatures,the capacity released by the cell with LHCE-2 electrolyte is significantly higher than that of HCE and conventional EC-based ***,the LHCE-2 electrolyte inherits the advantages of TTE flame-resistant,thus improving the safety of the battery.

关键词： Lithium-ion batteries propylene carbonate Localized high-concentration electrolyte Non-Inert diluent Graphite||NMC622 pouch cells

A facile and efficient dry transfer technique for two-dimensional Van der Waals heterostructure

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Chinese Physics B 2017年第8期26卷 417-422页

作者：谢立杜罗军卢晓波杨蓉时东霞张广宇 Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences(CAS)Beijing 100190China School of Physical Science University of Chinese Academy of SciencesBeijing 100190China Collaborative Innovation Center of Quantum Matter Beijing 100190China Beijing Key Laboratory for Nanomaterials and Nanodevices Beijing 100190China

Two-dimensional （2D） Van der Waals heterostructures have aroused extensive concerns in recent years. Their fabrica- tion calls for facile and efficient transfer techniques for achieving well-defined structures. In this work, we report a simple and effective dry transfer method to fabricate 2D heterostructures with a clean interface. Using propylene carbonate （PC） films as stamps, we are able to pick up various 2D materials flakes from the substrates and unload them to the receiving substrates at an elevated temperature. Various multilayer heterostructures with ultra-clean interfaces were fabricated by this technique. Furthermore, the 2D materials can be pre-pattemed before transfer so as to fabricate desired device structures, demonstrating a facile way to promote the development of 2D heterostructures.

关键词： two-dimensional materials Van der Waals heterostructure propylene carbonate transfer

One-pot Synthesis of Dimethyl carbonate in the Presence of a Two-component Catalyst

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Chemical Research in Chinese Universities 2005年第6期21卷 714-717页

作者： CHEN Xiu-zhi HU Chang-wen GAO Zhi-ming The Institute for Chemical Physics Beijing Institute of Technology Beijing 100081 P. R. China Department of Chemistry Beijing Institute of Technology Beijing 100081 P. R. China

The one-pot synthesis of dimethyl carbonate（DMC） with co-production of propy-lene carbonate（PC） and propylene glycol（PG） from propylene oxide（ PO）, carbon dioxide and methanol as the starting materials was investigated. The catalyst adopted here was a mixture of tetrabutyl ammonium bromide and sodium methoxide. It was found that un- der the reaction conditions of t = 150 ℃, p =3-4 MPa and 2 h, the PO conversion could reach 100%, the DMC, PC and the PG selectivities were 49. 7%, 42. 7% and 49. 8%, respectively, and the selectivity of by-products was below 10%.

关键词： Dimethyl carbonate Carbon dioxide propylene oxide propylene carbonate Catalyst

Effect of Amine Type on Lignin Modification to Evaluate Its Reactivity in Polyol Construction for Non-Isocyanate Polyurethanes(NIPU)

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Journal of Renewable Materials 2023年第5期11卷 2171-2190页

作者： Saeed Kazemi Najafi Farhood Najafi Antonio Pizzi Fatemeh Hassani Khorshidi Rabi Behrooz Department of Wood Science and Technology Faculty of Natural ResourcesTarbiat Modares UniversityTehranIran Department of Resin and Additives Institute for Color Science and TechnologyTehranIran LERMAB University of LorraineBlvd des AiguillettesNancyFrance

Polyols are groups of organic compounds which contain carbon and are randomly linked to other atoms,especially carbon-carbon and *** compounds are mainly used as reactants to make other *** biopolymers,lignin is regarded as the base of a new polymer in polyol *** present study aimed to investigate the effects of amine type(diethylenetriamine and ethylenediamine)on the modification of lignin-based polyols,so as to provide an alternative to petroleum polyols and,in turn,increase functional groups and reduce their harm to humans’health and the *** this aim,first,lignin was extracted from raw ***,the extracted lignin was reacted with diethylenetriamine(DETA)and ethylenediamine(EDA).Finally,the Mannich method was used for the reaction between amine lignin and propylene *** results of the Fourier Transform Infrared(FTIR)spectroscopy analysis showed that modification with DETA led to more structural change in lignin and peak 1100 indicates the presence of C–O bond related to urethane bonds in modified ***,adding propylene carbonate to aminated lignin did not result in much change in the results of the FTIR ***,urethane bonds can be seen in the results of GPC at 400℃–500℃.Furthermore,a slight decrease in thermal stability was observed in lignin modified with amine and propylene carbonate,compared to the raw lignin sample.

关键词： Polyol lignin diethylenetriamine ethylenediamine propylene carbonate polyurethanes NIPU