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Efficient oxidation of monosaccharides to sugar acids under neutral condition in flow reactors with gold-supported activated carbon catalysts

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FRONTIERS OF CHEMICAL SCIENCE AND ENGINEERING 2024年第9期18卷 106-0页

作者： Gong, Ziqin Li, Zengyong Zeng, Xu Yue, Fengxia Lan, Wu Liu, Chuanfu South China Univ technol Sch Light Ind & Engn State Key Lab Pulp & Paper Engn Guangzhou 510640 Peoples R China anhui Agr Univ Anhui Prov Engn Ctr High Performance Biobased Nylo Sch Mat & Chem Hefei 230036 Anhui Peoples R China

A significant reaction in the synthesis of biomass-based chemicals is the catalyst-based and targeted oxidation of monosaccharides into valuable sugar acids. In this study, an activated carbon supported gold catalyst was used to oxidize glucose and xylose to gluconic acid and xylonic acid under neutral condition. Optimization of reaction conditions for the catalysts was performed using both a batch reactor and a flow-through reactor. In a batch reactor, the yields of gluconic and xylonic acid reached 93% and 92%, respectively, at 90 degrees C within 180 min. In a flow reactor, both reactions reached a similar yield at 80 degrees C with the weight hourly space velocity of 47.1 h-1. The reaction kinetics were explored in the flow reactor. The oxidation of glucose and xylose to gluconic and xylonic acid followed a first-order kinetics and the turnover frequency was 0.195 and 0.161 s-1, respectively. The activation energy was evaluated to be 60.58 and 59.30 kJmol-1, respectively. This study presents an environmentally friendly and feasible method for the selective oxidation of monosaccharides using an activated carbon supported gold catalyst, benefiting the high-value application of carbohydrates.

关键词： monosaccharides oxidation gluconic acid xylonic acid flow reactor kinetics BASE-FREE OXIDATION SELECTIVE OXIDATION NIOBIUM PHOSPHATE AEROBIC OXIDATION GLUCONIC ACID DEFECT-RICH BIOMASS NANOPARTICLES PERFORMANCE DERIVATIVES

Approximate constructions of counterdiabatic driving with NMR quantum systems

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CHINESE PHYSICS B 2024年第9期33卷 83-91页

作者： Zhou, Hui Dai, Xiali Geng, Jianpei Ji, Yunlan Peng, Xinhua Hefei Univ technol Sch Phys Hefei 230009 Peoples R China Univ Sci & technol China Chinese Acad Sci Key Lab Microscale Magnet Resonance Hefei 230026 Peoples R China Univ Sci & technol China Sch Phys Sci Hefei 230026 Peoples R China Univ Sci & technol China Chinese Acad Sci Ctr Excellence Quantum Informat & Quantum Phys Hefei 230026 Peoples R China Univ Sci & technol China Hefei Natl Lab Hefei 230088 Peoples R China

Counterdiabatic driving (CD) offers a fast and robust route to manipulate quantum systems, which has widespread applications in quantum technologies. However, for higher-dimensional complex systems, the exact CD term involving the spectral properties of the system is difficult to calculate and generally takes a complicated form, impeding its experimental realization. Recently, many approximate methods have been proposed for designing CD passages in many-body systems. In this topical review, we focus on the CD formalism and briefly introduce several experimental constructions and applications of approximate CD driving in spin-chain models with nuclear magnetic resonance (NMR) systems.

关键词： nuclear magnetic resonance quantum simulation quantum state engineering 03.67.-a 42.50.Dv 82.56.-b PURE STATES ALGORITHM DYNAMICS

Compressive strain in Cu catalysts: Enhancing generation of C2+ products in electrochemical CO2 reduction

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SCIENCE BULLETIN 2024年第18期69卷 2881-2891页

作者： Fan, Qikui Yan, Pengxu Liu, Fuzhu Xu, Zhongshuang Liang, Pengfei Cao, Xi Ye, Chenliang Liu, Moxuan Zhao, Lingyi Ren, Shan Miao, Huanran Zhang, Xiai Yang, Zhimao Ding, Xiangdong Yang, Jian Kong, Chuncai Wu, Yuen Xi An Jiao Tong Univ Sch Phys MOE Key Lab Nonequilibrium Synth & Modulat Condens Key Lab Adv Mat & Mesoscop Phys Shaanxi Prov Xian 710049 Peoples R China Xi An Jiao Tong Univ State Key Lab Mech Behav Mat Xian 710049 Peoples R China anhui Normal Univ Coll Chem & Mat Sci Wuhu 241002 Peoples R China North China Elect Power Univ Dept Power Engn Beijing 102206 Peoples R China Xian Univ Sci & technol Coll Chem & Chem Engn Xian 710054 Peoples R China Chinese Acad Sci Shenzhen Inst Adv Technol Ctr Mat & Interfaces Shenzhen 518055 Peoples R China Univ Sci & technol China Collaborat Innovat Ctr Chem Energy Mat iChEM Sch Chem & Mat Sci Hefei Natl Lab Phys Sci Microscale Hefei 230026 Peoples R China Univ Sci & technol China Natl Synchrotron Radiat Lab Hefei 230026 Peoples R China

Elastic strain in Cu catalysts enhances their selectivity for the electrochemical CO2 reduction reaction (eCO(2)RR), particularly toward the formation of multicarbon (C2+) products. However, the reasons for this selectivity and the effect of catalyst precursors have not yet been clarified. Hence, we employed a redox strategy to induce strain on the surface of Cu nanocrystals. Oxidative transformation was employed to convert Cu nanocrystals to CuxO nanocrystals; these were subsequently electrochemically reduced to form Cu catalysts, while maintaining their compressive strain. Using a flow cell configuration, a current density of 1 A/cm(2) and Faradaic efficiency exceeding 80% were realized for the C2+ products. The selectivity ratio of C2+/C1 was also remarkable at 9.9, surpassing that observed for the Cu catalyst under tensile strain by approximately 7.6 times. In-situ Raman and infrared spectroscopy revealed a decrease in the coverage of K+ ion-hydrated water (KH2O) on the compressively strained Cu catalysts, consistent with molecular dynamics simulations and density functional theory calculations. Finite element method simulations confirmed that reducing the coverage of coordinated KH2O water increased the probability of intermediate reactants interacting with the surface, thereby promoting efficient C-C coupling and enhancing the yield of C2+ products. These findings provide valuable insights into targeted design strategies for Cu catalysts used in the eCO(2)RR. (c) 2024 Science China Press. Published by Elsevier B.V. and Science China Press. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

关键词： Strain effect CO2 electroreduction to C2+ Catalytic selectivity Copper catalyst Water coverage SPEctrOSCOPY REVEALS CARBON-MONOXIDE COPPER SELECTIVITY ETHYLENE OPERANDO

Study on Process technology of Gas Bubbling Curtain Substituting Dam in the Tundish of Slab Casting

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Journal of Iron and Steel research International 2011年第S2期18卷 256-262页

作者： JIN You-lin, SHEN Chang, ZHANG Jian-ping, ZHANG Jian (technology Center of Ma’anshan Iron and Steel Co, Ltd , Ma’anshan 24300, anhui, China) Maanshan Iron & Steel Co Ltd Ctr Technol Maanshan 24300 Anhui Peoples R China

This paper presents experimental results from physical and mathematical simulation of liquid steel flow in the tundish adopting gas bubbling curtain substituting dam and industrial trials have been investigated based the experimental results. Physical and mathematical simulation results show the gas bubbling curtain can improve pattern of liquid flow in the tundish , accelerate inclusions flotation,and simultaneity metallurgy effect has been further improved when combining weir and turbulence inhibitor. The industrial trial results confirm that content of oxygen , nitrogen and inclusions in continuous casting billets have been reduced when gas bubbling curtain combining weir and turbulence inhibitor.

关键词： gas bubbling curtain physical simulation flow field optimization mathematical simulation

research on the Welding Process of 590MPa Grade High Strength Automobile Beam Steel

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Journal of Iron and Steel research International 2011年第S1期18卷 983-986页

作者： ZHANG Wu,HU Xue-wen,LIU Yong-gang,YANG Xing-liang,ZHANG Jian (technological Center,Maanshan Iron & Steel Co.,Ltd.,Maanshan243000,anhui,China) Maanshan Iron & Steel Co Ltd Ctr Technol Maanshan 243000 Anhui Peoples R China

590 MPa automobile beam steel strips are used mainly to manufacture the longitudinal beam of ***’s welding properties are critical to the safety of *** microstructure and mechanical properties of welding joints processed by CO 2 arc welding with different welding parameters were *** results showed that the welding joints were weak when welding heat input were small and the non metal inclusions were found in the weld joints when welding heat input are *** quality of the welding joints is good enough at 170A of the arc current and 24V of the arc *** the other welding parameters fixed,the incomplete fusion defect occurred in the welding joint with backward welding,but the quality of the welding joint is good with forward welding.

关键词： automobile beam steel CO 2 arc welding welding process

Investigation on Variation of Inclusions and Total Oxygen in IF Steel After RH Deoxidization

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Journal of Iron and Steel research International 2011年第S2期18卷 347-351页

作者： SHU Hong-fu1,2, LIU Liu1, LIU Xue-hua2, ZHANG Xiao-feng2 (1.Central Iron and Steel research Institute, Beijing 100081, China 2. technology Centre of Maanshan Iron and Steel Co Ltd, Maanshan 243000, anhui, China) Cent Iron & Steel res Inst Beijing 100081 Peoples R China Maanshan Iron & Steel Co Ltd Ctr Technol Maanshan 243000 Anhui Peoples R China

The variational regulation of inclusions and total oxygen in the IF Molten Steel during the RH refining process after deoxidization was studied. The results show that the relationship between total oxygen content and time is in accord with the following equation, T.O=271.25e-1.53t+23.49, R2=*** inclusion analysis investigation during RH pure circulation process indicates that the main inclusion of the IF molten steel after 2 minutes from the beginning of deoxidization is cluster inclusions of pure Al2O3 system. After 6 minutes from the aluminum deoxidization, the quantity of inclusion decreases and the inclusion style changes into block inclusions of Al2O3 system with the size of 5μm. In the other hand, some inclusions are of Al2O3-MgO. Complex inclusions of Al2O3-TiOx with the size of below 5μm, and the single particle or cluster complex inclusions with the typical square shape of Al2O3-TiN system are found after 3 minutes from titanium-ferrous alloy added. Then, the content of titanium of complex inclusions of Al2O3-TiOx decreases and the aluminum content rises along with the RH pure circulation time process. That means the inclusions of Al2O3-TiOx is not steady, and it trends to transfer into Al2O3.

关键词： IF steel inclusion RH refining

Effect of Sulfur Contents on Fracture Toughness of Wheel Steels for High Speed Train

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Journal of Iron and Steel research International 2011年第S1期18卷 366-371页

作者： MA Yue 1,PAN Tao 1,JIANG Bo 2,YANG Cai-fu 1,SU Hang 1,CUI Yin-hui 2,CHEN Gang 2 (1.Division of Structural Materials,Central Iron and Steel research Institute,Beijing 100081,China 2.technology Centre,Ma’anshan Iron and Steel Co Ltd.,Ma’anshan 243000,anhui,China) Cent Iron & Steel res Inst Div Struct Mat Beijing 100081 Peoples R China Maanshan Iron & Steel Co Ltd Ctr Technol Maanshan 243000 Anhui Peoples R China

The effect of different contents of S on fracture toughness of railway wheel steels for high speed train has been *** results show that there are kinds of non-metallic inclusion when O content retaining at about 10×10-6,such as Al 2 O 3 inclusions and Al 2 O 3 +MnS complex inclusions and single MnS *** is connected with S content level in *** toughness of railway steel increase obviously because of Al 2 O 3 covered by MnS around when S content is increase to about 70×*** shows that,after Al 2 O 3 covering by MnS around,stresses around complex inclusion decrease rapidly till disappear when analyzed by tessellated stresses *** is the reason of fracture toughness rise.

关键词： railway wheel steels fracture toughness inclusions tessellated stresses

Profile of Dr. Zhigang Tian

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Science China(Life Sciences) 2018年第12期61卷 1474-1476页

作者： Tian, Zhigang Univ Sci & technol China Hefei Anhui Peoples R China Chinese Acad Sci Inst Immunol Beijing Peoples R China Chinese Acad Sci Key Lab Innate Immun & Chron Dis Beijing Peoples R China USTC Med Ctr Hefei Anhui Peoples R China USTC Sch Life Sci Hefei Anhui Peoples R China

*** Tian's laboratory is credited with seminal discoveries regarding basic knowledge and clinical study of natural killer(NK)cells,particularly liver-resident NK cells, cytokine-producing NK cell subsets,and NK cell-based *** has made outstanding contributions in the field of NK cell research,and was elected as a member of the Chinese Academy of Engineering in 2017.

关键词： Tian's laboratory the Chinese Academy

Photodegradation of methyl orange by BiOI-sensitized TiO_2

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Rare Metals 2012年第6期31卷 604-610页

作者： Li Huiquan Cui Yumin Hong Wenshan Hua Lin Tao Dongliang Fuyang Normal Coll Sch Chem & Chem Engn Fuyang 236041 Peoples R China anhui Prov Key Lab Degradat & Monitoring Pollut E Fuyang 236041 Peoples R China Singapore Linovus technol Private Ltd Res Dist Ctr Singapore 059818 Singapore

BiOI-sensitized titanium dioxide (TiO2) photocatalysts were prepared by a deposition method at room temperature and characterized by X-ray diffraction, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller surface area measurements. The photocatalytic activities of the catalysts were evaluated for the degradation of methyl orange (MO) solution under UV and visible light irradiation. The effects of catalyst amount, initial pH value, initial concentration of MO, as well as KI amount were investigated. The repeatability of photocatalytic activity of the 1.7% BiOI/TiO2 catalyst was also tested. It is shown that BiOI sensitization enhances the photocatalytic activities of TiO2. With BiOI content increasing, the photocatalytic activities of BiOI/TiO2 under UV and visible light irradiation first increase, reaching a maximum around BiOI content of 1.7%, and then decrease with further increasing BiOI content. The 1.7% BiOI/TiO2 catalyst obviously exhibits much higher visible light photocatalytic activity than P25, and its UV light photocatalytic activity is slightly higher than that of P25. Under the conditions of a catalytic dose of 1.5 g.L-1, initial pH of 3.0, initial MO concentration of 20 mg.L-1, UV power of 300 W, and air flow rate of 0.8 ***-1, complete degradatio is achieved within 60 min. The repeatability of photocatalytic activity of the 1.7% BiOI/TiO2 catalyst is highly reliable.

关键词： sensitized TiO2 BiOI photocatalytic degradation methyl orange