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Chinese Chemical Letters 2005年第11期16卷 1441-1444页

作者： Jing Chao TAO Guo Qiang TIAN Yan Bing ZHANG Yu Qin fu gui fu dai Ya WU Department of Chemistry Zhengzhou University Zhengzhou 450052

In this paper, two new compounds, ent-16α-hydroxy-15β-hydroxymethylbeyeran-19-oic acid 4 and its ethyl ester 5 were synthesized in good yield with a facile method that has never been reported. The mechanism of this reaction was discussed and the mono-hydroxymethylation of carbonyl compound with two α-hydrogens via Tollens＇ reaction was firstly achieved. Compounds 2-5 were tested for activity of inhibition against glycosidases, among which 5 displays good inhibition of β-glucosidase and α-mannase, respectively.

关键词： Isosteviol 1,3-diol hydroxylation.

Novel pyrazole fused heterocyclic ligands:Synthesis,characterization,DNA binding/cleavage activity and anti-BVDV activity

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Chinese Chemical Letters 2015年第5期26卷 534-538页

作者： Chao Han Yan-Chun Guo Dan-Dan Wang Xing-Jie dai Feng-Juan Wu Huan-Fei Liu gui-fu dai Jing-Chao Tao College of Chemistry and Molecular Engineering Zhengzhou University School of Life Sciences Zhengzhou University

A series of novel pyrazole fused heterocyclic derivatives were synthesized via a two-step procedure or a one-pot two step method, and their catalytic DNA cleavage abilities and anti-BVDV activities were also evaluated. The results obtained indicated that compounds 3b-3c could catalyze the cleavage of supercoiled DNA （pUC 19 plasmid DNA） to nicked DNA under physiological conditions with high yields via a hydrolytic mechanism. The studies on anti-viral activities against bovine viral diarrhea virus （BVDV） demonstrated that some of the pyrazole derivatives showed pronounced anti-BVDV activity with interesting ECso values and no significant cytotoxicity. Among them, compound 31 showed the highest antiviral activity （ECso = 0.12 μmol/L） and was 10 fold more than that of the positive control ribavirin （ECso = 1.3 μmol/L）, which provided a potential candidate for the development of anti-BVDV agents.

关键词： Synthesis Tetramic acids DNA binding/cleavage Pyrazole derivatives Anti-BVDV

Synthesis and Bioactivity of Isosteviol Derivatives: A Facile Method for Preparation of Ent-16α-hydroxy-15β-hydroxymethylbeyeran-19-oic Acid

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Chinese Chemical Letters 2005年第11期 25-28页

作者： Jing Chao TAO, Guo Qiang TIAN, Yan Bing ZHANG, Yu Qin fu, gui fu dai, Ya WU Department of Chemistry, Zhengzhou University, Zhengzhou 450052 Department of Chemistry Zhengzhou University Zhengzhou 450052

In this paper, two new compounds, ent-16α-hydroxy-15β-hydroxymethylbeyeran-19-oic acid 4 and its ethyl ester 5 were synthesized in good yield with a facile method that has never been reported. The mechanism of this reaction was discussed and the mono-hydroxymethylation of carbonyl compound with two α-hydrogens via Tollens’ reaction was firstly achieved. Compounds 2-5 were tested for activity of inhibition against glycosidases, among which 5 displays good inhibition of β-glucosidase and α-mannase , respectively.

关键词： Isosteviol 1 3-diol hydroxylation

Synergistic Effect in Special Selectivity Mixed Gas Chromatographic Stationary Phase in the Separation of Aromatic Compounds

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Chinese Chemical Letters 1998年第2期9卷 151-155页

作者： Yuan, LM fu, RN gui, SH Chen, XX dai, RJ Yunnan Normal Univ Dept Chem Kunming 650092 Peoples R China Beijing Inst Technol Dept Chem Engn Beijing 100081 Peoples R China Yunnan Normal Univ Solar Energy Res Inst Kunming 650092 Peoples R China

The gas chromatographic separations of aromatic compounds using special mixed stationary phases consisting of pp-beta-CD+AgNO3, pp-beta-CD+TINO3, pp-beta-CD+di-n-butly phthalate, pp-beta-CD+BPBHpB liquid crystalline, and bentone-34+AgNO3 were investigated. Besides pp-beta-CD+di-n-butyl phthalate, most of the separations deviated from the additivity and a synergistic effect was observed. The separation effects depend on the temperature and how mixing is accomplished.

关键词： gas chromatography mixed stationary phase synergistic effect aromatic compounds

Robust Feedback Set Stabilization of Logic Networks with State-Dependent Uncertain Switching and Control Constraints

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Journal of Systems Science & Complexity 2024年第2期37卷 629-646页

作者： dai Chaoqun GUO Yuqian gui Weihua School of Automation Central South UniversityChangsha 410083China

This study investigates the robust feedback set stabilization of switched logic control networks(SLCNs)with state-dependent uncertain switching and control ***,based on the properties of the semi-tensor product of matrices and the vector representation of logic,an SLCN with state-dependent uncertain switching and control constraints is expressed in algebraic ***,an input transformation and a switching model are constructed to transfer the original SLCN into one with a free control input and arbitrary *** equivalence between the set stabilizability of the original SLCN and that of the resulting SLCN is *** on such equivalence,the authors propose a necessary and sufficient condition for robust feedback set ***,an example is presented to demonstrate the application of the results obtained.

关键词： Input transformation robust control invariant subset robust feedback set stabilizability semi-tensor product state-dependent constraints switched logic control network

Study on detinning process of a reflow conductor roll

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Rare Metals 2005年第4期24卷 325-329页

作者： fu Hanguang dai Mingshan fu Hanfeng Department of Mechanical Engineering Tsinghua University Beijing 100084 China Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China

Adhering tin is the main reason of a reflow conductor roll which works in an electroplating tin line （ETL）. A det- inning agent whose main composition is NaOH and KOH and assistant composition is Na2PbO2 or K2PbO2 and NaNO3 or NaNO2 has excellent detinning effects when the temperature of detinning solution is 40-80℃ and the temperature of the reflow conductor roll reaches 40-70℃. After the adhering tin layer of the reflow conductor roll is removed, the roughness of the reflow conductor roll can resume to 4.0 μm, its service life increases by 80%, and the repairing cost decreases by 90%.

关键词： electroplating tin reflow conductor roll detinning agent roughness

Anaerobic co-digestion of thermo-alkaline pretreated microalgae and sewage sludge: Methane potential and microbial community

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Journal of Environmental Sciences 2023年第5期127卷 133-142页

作者： Jiaqi fu Bing Yan Shuanglin gui Yinxuan fu Song Xia Institute of Energy Research Jiangxi Academy of SciencesNanchang 330096China

To improve methane production from sewage sludge(SS),co-digestion of SS and microalgae(MA)was studied and the application of thermo-alkaline pretreatment to MA was *** results showed that thermo-alkaline pretreatment at 90℃ for 120 min on MA was the optimum pretreatment ***,when the volatile solids(VS)ratio of SS and MA was 1:2,the methane yield reached maximum(368.94 mL/g VS).Fourier transform infrared(FT-IR)and thermogravimetric analysis confirmed the synergetic effects of thermoalkaline pretreated MA on its co-digestion with *** analyses of microbial community indicated that Methanobacterium and Methanosarcina were the dominant methanogens during the co-digestion ***,the relative abundance of Methanosarcina in thermoalkaline pretreated groups was higher compared to unpretreated *** microbial community structure might be affected by thermo-alkaline pretreatment rather than by the MA dosage in the co-digestion.

关键词： Anaerobic co-digestion Thermo-alkaline pretreatment Microalgae Sewage sludge Microbial community

Graphitic carbon nitride/antimonene van der Waals heterostructure with enhanced photocatalytic CO_(2) reduction activity

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Journal of Materials Science & Technology 2022年第21期116卷 192-198页

作者： Jinfeng Zhang Junwei fu Kai dai Key Laboratory of Green and Precise Synthetic Chemistry and Applications Ministry of EducationHuaibei Normal UniversityHuaibei 235000China School of Physics and Electronics Central South UniversityChangsha 410083China

Photocatalytic reduction of CO_(2) into valuable fuels is one of the potential strategies to solve the carbon cycle and energy *** carbon nitride(g-C_(3)N_(4)),as a typical two-dimensional(2D)semiconductor with a bandgap of∼2.7 eV,has attracted wide attention in photocatalytic CO_(2) ***,the performance of g-C_(3)N_(4) is greatly limited by the rapid recombination of photogenerated charge carriers and weak CO_(2) activation *** of van der Waals heterostructure with the maximum interface contact area can improve the transfer/seperation efficiency of interface charge *** metal antimony(Sb)nanosheet(antimonene)with high carrier mobility and 2D layered structure,is a good candidate material to construct 2D/2D Sb/g-C_(3)N_(4) van der Waals *** this work,the density functional theory(DFT)calculations indicated that antimonene has higher carrier mobility than g-C_(3)N_(4) *** charge transfer and in-plane structure distortion will occur at the interface of Sb/g-C_(3)N_(4),which endow stronger CO_(2) activation ability on di-coordinated N active *** ultrathin g-C_(3)N_(4) and antimonene nanosheets were prepared by ultrasonic exfoliation method,and Sb/g-C_(3)N_(4) van der Waals heterostructures were constructed by self-assembly *** photoluminescence(PL)and time-resolved photoluminescence(TRPL)indicated that the Sb/g-C_(3)N_(4) van der Waals heterostructures have a better photogenerated charge separation efficiency than pure g-C_(3)N_(4) ***-situ FTIR spectroscopy demonstrated a stronger ability of CO_(2) activation to^ (∗)COOH on Sb/g-C_(3)N_(4) van der Waals *** a result,the Sb/g-C_(3)N_(4) van der Waals heterostructures showed a higher CO yield with 2.03 umol g^(−1) h^(−1),which is 3.2 times that of pure g-C_(3)N_(4).This work provides a reference for activating CO_(2) and promoting CO_(2) reduction by van der Waals heterostructure.

关键词： Photocatalysis Carbon nitride Antimonene Van der Waals heterostructure CO_(2)activation

In situ synthesis and hardness of TiC/Ti_5Si_3 composites on Ti-5Al-2.5Sn substrates by gas tungsten arc welding

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International Journal of Minerals,Metallurgy and Materials 2013年第3期20卷 284-289页

作者： Wen-qing Yan Le dai Chi-bin gui School of Mechanical and Automotive Engineering South China University of Technology School of Materials and Metallurgy Wuhan University of Science and Technology Military Representative Office of Navy 407 Factory College of Materials Science and Engineering Huazhong University of Science and Technology

TiC/TisSi3 composites were fabricated on Ti-5A1-2.5Sn substrates by gas tungsten arc welding （GTAW）. Identification of the phases was performed using X-ray diffraction （XRD）. The microstructures were analyzed using scanning electron microscopy （SEM） combined with energy-dispersive X-ray spectrometry （EDS） and optical microscopy （OM）. The Vickers hardness was measured with a micro-hardness tester. The TiC/TisSi3 composites were obtained in a double-layer track, and the Vickers hardness of the track increased by two to three times compared with the Ti-5A1-2.5Sn substrate.

关键词： titanium alloys surface modification gas tungsten arc welding (GTAW) microstructure hardness

High-temperature mechanical properties of near-eutectoid steel

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International Journal of Minerals,Metallurgy and Materials 2013年第9期20卷 829-834页

作者： Jun fu fu-ming Wang Fang Hao gui-xiang Jin State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The high-temperature mechanical properties of near-eutectoid steel were studied with a Cleeble-1500 simu- lation machine. Zero strength temperature （ZST）, zero ductility temperature （ZDT）, hot ductility curves, and strength curves were measured. Two brittle zones and one plastic zone were found in the temperature range from the melting point to 600℃. Embrittlement in zone I is caused by the existence of liquid film along dendritic interfaces. Ductility loss in zone Ⅲ mainly results from precipitates and inclusions as well as S segregation along grain boundaries. Pearlite transformation also accounts for ductility deterioration in the temperature range of 700-600℃. Moreover, the straightening temperature of the test steel should be higher than 925℃ for avoiding the initiation and propagation of surface cracks in billets.

关键词： carbon steel eutectic alloys high temperature properties mechanical properties brittleness straightening billets