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Achieving higher performances without an external curing agent in natural magnolol-based epoxy resin

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Chinese Chemical Letters 2022年第4期33卷 2195-2199页

作者： Qi Cao Zhihuan Weng Yu Qi Jiahui Li Wentao Liu Chengde Liu Shouhai Zhang Zhiyong Wei Yousi Chen Xigao Jian State Key Laboratory of fine chemicals Liaoning High Performance Resin Engineering Research CenterDepartment of Polymer Science&EngineeringDalian University of TechnologyDalian 116024China

Bio-based epoxy thermoset prepared from renewable biomass raw materials can alleviate fossil energy crisis and reduce environmental pollution,which satisfies the needs of sustainable social *** this study,a bio-based epoxy thermoset precursor(MGOL-EP) was synthesized from a naturally occurring magnolol through a facile and efficient one-step *** the fully bio-based epoxy thermoset(MGOL-EP-SC) was obtained by self-curing without adding any other ***-EP-SC revealed an extremely high glass-transition temperature(T_(g)) of 265℃ and char yield of 53.2%(in N;),which were at the highest level among the fully bio-based epoxy thermosets reported so *** addition,when the MGOL-EP was cured with 4,4’-methylenedianiline(DDM),T_(g)of the MGOL-EP/DDM was decreased by 61℃ and the other comprehensive performance had also been decreased,which was due to a reduction in biphenyl structure content and cross-linking density by adding the external curing ***,the MGOL-EP-SC presented certain killing rate(48.4%) to Staphylococcus *** findings provide a new design strategy for engineering high-performance and functional epoxy thermoset with high biomass content.

关键词： Epoxy resin Magnolol Self-curing Fully bio-based Antimicrobial properties

Lifetime-tunable circularly polarized luminescent system based on triplet-to-singlet Förster resonance energy transfer

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Science China Chemistry 2024年第9期67卷 2918-2922页

作者： Zhenyi He Zizhao Huang Xiang Ma Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint research center Institute of Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Circularly polarized luminescence(CPL)materials have received widespread attention due to their remarkable performance and broad ***,current CPL material research primarily focuses on tunable color,intensity,and *** CPL with adjustable lifetime remains a significant ***,a series of CPL polymeric materials with tunable lifetime were obtained by employing phosphorescent terephthalic acid and chiral organic small molecule R/S-BNAF(a luminescent binaphthol derivative)to copolymerize with acrylamide in different *** was verified that this performance results from the different energy transfer efficiency between luminophores with varying ratios of the monomers for *** strategy to realize CPL with tunable lifetime by modulating the energy transfer efficiency will provide a new perspective to broaden the applications of CPL materials.

关键词： circularly polarized luminescence tunable lifetime Förster resonance energy transfer room temperature phosphorescence

Tunable room-temperature phosphorescence and circularly polarized luminescence encoding helical supramolecular polymer

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Science China Chemistry 2022年第1期65卷 75-81页

作者： Chen Xu Chenjia Yin Wenjun Wu Xiang Ma Key Laboratory for Advanced Materials and Feringa Nobel Prize Scientist Joint research center Frontiers Science Center for Materiobiology and Dynamic ChemistryInstitute of Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China

Supramolecular polymers with different functionalities have been continuously developed in the past decade because of their indispensable role in soft ***,pure organic supramolecular polymers with stable room temperature phosphorescence(RTP)emission were very rarely reported for the difficulties of synthesis and achieving RTP in ***,soluble helical supramolecular polymers with circularly polarized room-temperature phosphorescence were developed via a facile hostguest *** assembly,a transition from pure fluorescence to almost pure RTP emission was *** the asymmetry of guest could easily control the chiroptical property of supramolecular *** work provides new opportunities for the design and development of intelligent soft functional soft materials.

关键词： room-temperature phosphorescence circularly polarized luminescence supramolecular polymer helical handedness

Application of rare earths in fluid catalytic cracking： A review

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Journal of Rare Earths 2017年第10期35卷 941-956页

作者： Aaron Akah research and development center Saudi Aramco Dhahran 31311 Saudi Arabia

The need for more active and hydrothermally stable fluid catalytic cracking（FCC）catalysts to combat the effect of metal contaminants has led to an increase in demand for rare earth *** earth oxides enhance catalyst activity and prevent the loss of acid sites during the FCC unit operation,especially when heavy residue with high metal content is used as *** this paper,a review was carried out to show the effects of rare earth elements on the structure,activity,and stability of FCC ***,the use of rare earth elements as vanadium traps was analyzed in conjunction with the mechanism of catalyst deactivation by *** objective was to elucidate the interaction of vanadium species with the zeolite component of the FCC catalysts and the role of rare earth elements in countering the deleterious effects of vanadium on the FCC catalysts.

关键词： FCC catalyst rare earth vanadium trap zeolites

Growth and Characteristics of Tunable Laser Crystals β-Ga2O3∶Cr

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Journal of Rare Earths 2006年第z1期24卷 156-158页

作者： Zhang Jungang Xia Changtai Deng Qun Xu Wusheng Shi Hongsheng Wu Feng Xu Jun Shanghai Institute of Optics and fine Mechanics Chinese Academy of Sciences Shanghai 201800 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China GE (China) Research and Development Center Co. Ltd. Shanghai 201203 China GE (China) Research and Development Center Co. Ltd. Shanghai 201203 China GE (China) Research and Development Center Co. Ltd. Shanghai 201203 China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China

β-Ga2O3∶Cr single crystals have potential applications for tunable laser. In β-Ga2O3 crystal structure Cr3+ ions are in octahedron other than tetrahedron. So the Cr3+ ions are influenced by low field of β-Ga2O3 that results the 4T2 to 4A2 transition and show broad emission around 690 nm. β-Ga2O3 single crystals doped with different Cr3+ concentrations were grown by floating zone technique. Their absorption spectra and fluorescence spectra were measured at room temperature. The values of field splitting parameter Dq and Racah parameter B were calculated based on the absorption spectra.

关键词： β-Ga2O3 Cr floating zone technique tunable laser

development of solid base catalyst X/Y/MgO/-Al_(2)O_(3) for optimization of preparation of biodiesel from Jatropha curcas *** oil

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Frontiers of Chemical Science and Engineering 2008年第4期2卷 468-472页

作者： Rui WANG Song YANG Shitao YIN Baoan SONG Pinaki SBHADURY Wei XUE Shuwei TAO Zhaohui JIA Da LIU Liang GAO center for research and development of fine chemicals Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of EducationGuizhou UniversityGuiyang 550025China Department of Biology and Environment Engineering Guiyang CollegeGuiyang 550005China

The preparation and regeneration conditions of the identified catalyst X/Y/MgO/?-Al2O3 with high catalytic activity were studied and optimized. The biodiesel was prepared by transesterification of Jatropha curcas seed oil produced in Guizhou with methanol at its reflux temoerature in the presence of X/Y/MgO/?-Al2O3 . The pilot plant tests were carried out in a 100 L reaction vessel. Both average yield and fatty acid methyl esters (FAME) content reached more than 96.50% under the optimum reaction conditions of the pilot plant tests designed with an oil/methanol molar ratio of 1 : 10, catalyst concentration of 1.00%, and reaction time of 3 h at reflux temperature. In addition, analysis shows that the quality of biodiesel meets the standard EN 14214.

关键词： Solid base catalyst Jatropha curcas oil Transesterification reaction Pilot plant test

Effects of oxygen partial pressure on optical absorption edge and UV emission energy of ZnO films

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Chinese Optics Letters 2005年第7期3卷 428-431页

作者：洪瑞金邵建达贺洪波范正修 research and development center for Optical Thin Film Coatings Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences Shanghai 201800Graduate School of Chinese Academy of Sciences Beijing 100864Received September 15 2004 research and development center for Optical Thin Film Coatings Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences Shanghai 201800

The optical absorption edge and ultraviolet (UV) emission energy of ZnO films deposited by direct current (DC) reactive magnetron sputtering at room temperature have been investigated. With the oxygen ratio increasing, the structure of films changes from zinc and zinc oxide coexisting phase to single-phase ZnO and finally to the highly (002) orientation. Both the grain size and the stress of ZnO film vary with the oxygen partial pressure. Upon increasing the oxygen partial pressure in the growing ambient, the visible emission in the room-temperature photoluminescence spectra was suppressed without sacrificing the band- edge emission intensity in the ultraviolet region. The peaks of photoluminescence spectra were located at 3.06—3.15 eV. Prom optical transmittance spectra of ZnO films, the optical band gap edge was observed to shift towards shorter wavelength with the increase of oxygen partial pressure.

关键词： Film preparation Grain size and shape Light absorption Magnetron sputtering Oxygen Partial pressure Photoluminescence Ultraviolet spectroscopy Zinc oxide

Two near-infrared highly sensitive cyanine fluorescent probes for pH monitoring

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Chinese Chemical Letters 2017年第8期28卷 1681-1687页

作者： Jing-Ru Hou Di Jin Bo Chen Lei-Lei Si Yue-Hua Jin Li-Gong Chen Xi-Long Yan Bo-Wei Wang Yang Li School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China Collaborative Innovation center of Chemical Science and Engineering Tianjin 300350China Tianjin Bohai fine Chemical Co. Ltd.Tianjin 300300China Tianjin Engineering research center of Functional fine chemicals Tianjin 300350China

Two near-infrared（NIR） p H-activated heptamethine indocyanine probes with quaternary ammonium unit were designed and synthesized. The absorption and emission titrations indicate that cationic structure improves the cyanine dye＇s aqueous solubility and these two probes exhibit highly sensitive response to p H in acid condition. Their fluorescence intensities both gradually increase about 25-fold from p H 7.60 to 3.00 with p Ka values of 4.72 and 4.45 respectively, which are suitable for studying acidic organelles in living cells. Moreover, their fluorescence intensities are linearly proportional to p H values in the range of 5.50–4.00. These results are probably attributed to the protonation of the indole nitrogen atoms, which are verified by 1H NMR spectra. Furthermore, these two probes can achieve real-time imaging of cellular p H and detection of p H in situ in living He La cells due to their excellent properties,including good reversibility, desirable photostability, high selectivity, low cytotoxicity and remarkable membrane permeability.

关键词： pH fluorescent probe Near-infrared Indocyanine Quaternary ammonium Biological imaging

Synthesis and antiviral activities of novel 1,4-pentadien-3-one derivatives bearing an emodin moiety

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Chinese Chemical Letters 2016年第6期27卷 948-952页

作者： Jian Wu Yun-Ying Zhu Yong-Hui Zhao Wei-Li Shan De-Yu Hu Ji-Xiang Chen Deng-Yue Liu Xiang-Yang Li Song Yang State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural BioengineeringMinistry of Education Research and Development Center for Fine Chemicals Guizhou University School of Chemical Engineering Guizhou Institute of Technology Institute for the Control of Agrochemicals Ministry of Agriculture

A series of 1,5-diaryl-1,4-pentadien-3-one derivatives bearing an emodin group were designed and synthesized by the combination of natural products. The antiviral activities against tobacco mosaic virus（TMV） and cucumber mosaic virus（CMV） in vivo were evaluated. Some of the derivatives displayed promising curative effect and protective activity against TMV. Compound D5 showed appreciable curative bioactivity on TMV approximately of 50% at 306.2 mg/m L, which was superior to ningnanmycin（409.3 mg/m L）.

关键词： 1 4-Pentadien-3-one derivatives Emodin Synthesis Antiviral activity