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Preparation of a cationic azobenzene dye-montmorillonite intercalation compound and its photochemical behavior

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Journal of University of Science and Technology Beijing 2006年第3期13卷 281-286页

作者： Tao wan yi Yuan Wenqiong He College of Materials and Chemistry ＆ Chemical Engineering Chengdu University of Technology Chengdu 610059 China

Montmorillonite/cationic azobenzene dye （GTL） intercalation compounds were prepared by the conventional ion exchange method. As compared with that of pure GTL, the thermal stability of the intercalated GTL was greatly enhanced, and the absorption band corresponding to azobenzene group in intercalated GTL shifted towards a longer wavelength by 55 nm, which could be ascribed to the strong conjugation of GTL supramolecular order structure （J cluster） confined in a nanoscale space of montmorillonite interlayer gallery. The microstructures of the resulting intercalation compounds could be successfully controlled by varying the amount of dye loaded as evidenced by the basal spacing of the intercalation compounds. The intercalated azo dye in the montmorillonite interlayer space exhibited reversible trans-to-cis photoisomerization and thermal cis-to-trans reaction. FTIR proved the successful intercalation of GTL into the silicate layer.

关键词： Na-montmorillonite azobenzene intercalation photoisomerization

Solid-phase extraction and separation of indium with P_(2)O_(4)-UiO-66-MOFs (di-2-ethylhexyl phosphoric acid-UiO-66-metal-organic frameworks)

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Journal of Environmental Sciences 2023年第5期127卷 833-843页

作者： wan-yi Zeng Minzhong Huang Minglai Fu Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China School of Electromechanical Engineering Guangdong University of TechnologyGuangzhou 510006China Xiamen Key Laboratory of Municipal and Industrial Solid Waste Utilization and Pollution Control College of Civil EngineeringHuaqiao UniversityXiamen 361021China

Compared with the traditional liquid–liquid extraction method,solid-phase extraction agents are of great significance for the recovery of indium metal due to their convenience,free of organic solvents,and fully exposed *** this study,P_(2)O_(4)(di-2-ethylhexyl phosphoric acid)was chemically modified by using UiO-66 to form the solid-phase extraction agent P_(2)O_(4)-UiO-66-MOFs(di-2-ethylhexyl phosphoric acid-UiO-66-metal-organic frameworks)to adsorb In(Ⅲ).The results show that the Zr of UiO-66 bonds with the P-OH of P_(2)O_(4) to form a composite P_(2)O_(4)-UiO-66-MOF,which was confirmed by X-ray photoelectron spectroscopy(XPS)and Fourier transform infrared spectroscopy(FT-IR).The adsorption process of indium on P_(2)O_(4)-UiO-66-MOFs followed pseudo first-order kinetics,and the adsorption isotherms fit the Langmuir adsorption isotherm *** adsorption capabilities can reach 192.8 mg/*** five consecutive cycles of adsorption-desorption-regeneration,the indium adsorption capacity by P_(2)O_(4)-UiO-66-MOFs remained above 99%.The adsorption mechanism analysis showed that the P=O and P-OH of P_(2)O_(4) molecules coated on the surface of P_(2)O_(4)-UiO-66-MOFs participated in the adsorption reaction of *** this paper,the extractant P_(2)O_(4) was modified into solid P_(2)O_(4)-UiO-66-MOFs for the first *** work provides a new idea for the development of solid-phase extractants for the recovery of indium.

关键词： P_(2)O_(4)-UiO-66-MOFs(di-2-Ethylhexyl phosphoric acid-UiO-66-metal-organic frameworks) Solid-phase extraction Adsorption Indium(III)

Synthesis of Diverse Oxetane Amino Acids via Visible-Light-Induced Photocatalytic Decarboxylative Giese-Type Reaction

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Chinese Journal of Chemistry 2024年第12期42卷 1341-1346页

作者： Haoliang Shi yi wan Yongqiang Zhang Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism Shanghai Key Laboratory of New Drug Designand School of PharmacyEast China University of Science and TechnologyShanghai200237 China

The divergent synthesis of versatile 3,3′-disubstituted oxetane amino acids by utilizing visible-light-induced photocatalytic decarboxylative Giese-type reaction has been demonstrated.3-Methyleneoxetane-derived substrates are readily available in a single-step and highly reactive as radical acceptors,allowing the production of versatile oxetaneγ-andα-amino acids in high yields.A distinct ring strain release-driven radical addition mechanism was preliminarily *** preparative power was further highlighted by the application in the synthesis of oxetane-containing dipeptides and azetidine amino acids,as well as the transformation of the product into novel oxetane-containing spiro-heterocycle pharmacophore.

关键词： Photoredox catalysis Decarboxylative Giese-type reaction Oxetane amino acids Amino acids Synthesis Radical reactions

Improvement in Time Efficiency in Numerical Simulation for Solid Propellant Rocket Motors(SPRM)

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推进技术 2018年第1期39卷 92-99页

作者： Valeriy BUCHARSKyi ZHANG Li-hui wan yi-lun Propulsion System Design Dept Dnipro National University Dnipro 49000 Ukraine School of Astronautics Beihang University Beijing 100191 China

The main purpose of the present work is to study the possibilities of reducing calculation time while maintaining the validity in the numerical simulation of the combustion product flow in SPRM *** ways of decreasing the calculation time-the use of numerical methods of high accuracy order,the reduction in spatial dimension of the problem,and the use of physical features of the processes in SPRM chamber while constructing a calculation model-were *** calculation data show that the use of these approaches makes it possible to reduce the time for solving the problems of SPRM simulation significantly(up to 100times).Also conclusions about the applicability of the mentioned above approaches in SPRM design were made.

关键词： Numerical simulation Solid propellant rocket motor Calculation time reduction

Performance analysis of optical multicast in a new switching structure

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The Journal of China Universities of Posts and Telecommunications 2007年第3期14卷 43-47页

作者： JIA Peng ZHANG Jie GU wan-yi Key Laboratory of Optical Communication and Lightwave Technologies Ministry of Education Beijing University of Posts and TelecommunicationsBeijing 100876 China

The emergence of new services demands multicast function in optical network. Because of the high cost and complex architecture of multicast capable （MC） node, splitter- sharing switch structure is introduced in which the light splitters are shared by all input signals. To accommodate to this situation, by extending resource ReSerVation protocol-traffic engineering （RSVP-TE） and open shortest path first-traffic engineering （OSPF-TE）, a new optical multicast mechanism is provided and the signaling flow and its finite state machine model are given. At the same time, a multicast routing algorithm in splitter-sharing optical network and a changing link weight policy to balance network traffic are proposed. Simulations in NSFNET show no matter with or without wavelength converters, when the number of splitters is 25% of that demanded by traditional MC nodes, the multicast performance has been close to the ideal circumstance. Wavelength converters and changing link weight help much in improving the traffic performance when the number of splitters is adequate.

关键词： splitter-sharing optical multicast optical network wavelength converter

Effect of Counterface Material on Friction and Wear Behavior of Ni-Cr-W-Al-Ti-MoS_2 Composites

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Chinese Journal of Aeronautics 2006年第B12期19卷 74-77页

作者： LI Jian-liang XIONG Dang-sheng wan yi Department of Materials Science and Engineering Nanfing University of Science and Technology Nanjing 210094 China

Ni-Cr-W-Al-Ti-MoS2 self-lubricating composites were prepared through the powder metallurgy （P/M） method. Their friction properties were investigated by a pin-on-disk tribometer in the range from the room temperature to 600 ℃. Alumina, silicon nitride and nickel-iron-sulfide alloys were selected as the counterface materials. Results indicate that the lowest friction coefficients under 0.22 can be obtained at 600℃ when rubbed against alumina. When rubbed against nickel-iron-sulfide alloys, are presented the lowest wear rates in the magnitude of 10^-6 mm^3/N-m, one order of magnitude lower than those when rubbed against ceramics. In the case of three rubbing pairs, the wear rates of the composite containing MoS2 present themselves inversely proportional to friction coefficients. With alumina ceramics used as a counterface, transfer films and glaze layers will form on the contact surface playing a main role in lubrication at high temperatures. However, when silicon nitride and nickel-iron-sulfide alloy are used, the lubricating transfer films appear not to be prominent.

关键词： powder metallurgy (P/M) high temperature solid lubrication Ni-based composite

Efficient and green tetrahydropyranylation and deprotection of alcohols and phenols by using activated carbon supported sulfuric acid

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Chinese Chemical Letters 2008年第8期19卷 893-896页

作者： Jin Hui Yang Xuan Zhang wan yi Liu Key Laboratory of Energy Sources ＆ Engineering Ningxia University Yinchuan 750021 China School of Chemistry and Chemical Engineering Ningxia University Yinchuan 750021 China

A simple, green and efficient method for the DHP protection of various alcohols and phenols and the subsequent removal of the corresponding protective group in the presence of a catalytic amount of the activated carbo... 详细信息

关键词： Tetrahydropyranylation Deprotection THP ethers Activated carbon

Poly(GMA/MA/MBAA)Copolymer Beads:a Highly Efficient Support Immobilizing Penicillin G Acylase

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Chinese Chemical Letters 2006年第1期17卷 129-132页

作者： Ping XUE Guan Zhong LU wan yi LIU Key Laboratory of Energy Source and Chemical Engineering Ningxia University Yinchuan 750021 Research Institute of Industrial Catalysis East China University of Science and Technology Shanghai 200237

The hydrophilic, macroporous and beaded ternary copolymer of glycidyl methacrylate （GMA）/methacrylamide（MA）/N,N＇-methylene-bis（acrylamide）（MBAA）was synthesized using the industrial agents by inverse suspension polymerization. The apparent activity of the immobilized penicillin G acylase reached 1096 IU/g for hydrolysis penicillin G on the beads with diameter of 0.11-0.13 ram, and it changed hardly after 50 cycles. It can be expected to be a good potential in industrial application,

关键词： Poly(GMA/MA/MBAA) copolymer beads penicillin G acylase immobilization,inverse suspension polymerization.

Non-volatile constituents and pharmacology of Chimonanthus: A review

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Chinese Journal of Natural Medicines 2019年第3期17卷 161-186页

作者： SHU Ren-Geng wan yi-Li wanG Xiao-Min School of Pharmacy Jiangxi University of Traditional Chinese Medicine School of Pharmacy China Pharmaceutical University School of Life Science Jiangxi University of Traditional Chinese Medicine

Chimonanthus plants widely distributed in southern area of China, which have a long history of edibles and medicine. Phytochemical investigations have shown that Chimonanthus produced 143 non-volatile constituents, including alkaloids, flavonoids, terpenoids, coumarins and others, which exhibit significant anti-oxidant, anti-bacterial, anti-cancer, anti-inflammatory, antihyperglycemic, antihyperlipidemic and other biological activities. On the basis of systematic reviewing of literatures, this article overviews the non-volatile constituents and pharmacology of Chimonanthus from domestic and foreign over the last 30 years(until June 2018), and may provide a useful reference for the further development of Chimonanthus.

关键词： Chimonanthus Non-volatile constituents Pharmacology Review