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Synthesis and Crystal Structure of 4-Azido-2,2,6,6-Tetramethylpiperidine-1-oxyl Free Radical

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Chinese Journal of Structural Chemistry 2006年第2期25卷 127-130页

作者： ZHOU Bao-Han chen Yun-feng YIN guo-Dong WU An-Xin Key Laboratory of Pesticide and Chemical Biology Ministry of Education College of Chemistry Central China Normal University Wuhan 430079 China

The title compound 4-azido-2,2,6,6-tetramethylpiperidine-l-oxyl （C9H17N4O, Mr = 197.27） has been synthesized and its structure was determined by single-crystal X-ray diffraction. The crystal belongs to triclinic, space group P1^- with a = 5.8464（12）, b = 8.2476（17）, c = 11.954（2） A°, a = 101.973（4）, β = 97.186（3）, γ, = 100.232（3）°, V = 546.98（19） ,A°^3, Z = 2, Dc= 1.198 g/cm^3, μ（MoKa） = 0.082 mm^-1, F（000） = 214, R = 0.0495 and wR = 0.1355 for 1677 observed reflections with I 〉 2σ（I）. X-ray analysis reveals that the six-membered ring adopts a chair conformation and the bond length of N（1）-O（1） is 1.2838（19）A°.

关键词： crystal structure nitroxide radical synthesis

SHTQS: a telephonebased Chinese spoken dialogue system

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Journal of Systems Engineering and Electronics 2005年第4期16卷 881-885页

作者： Mao Jiaju chen Qiulin Gao feng guo Rong Lu Ruzhan Dept. of Computer Science and Engineering Shanghai Jiaotong Univ. Shanghai 200030 P. R. China

SHTQS is an intelligent telephone-besed spoken dialyze system providing the infomation about the best route between two sites in Shanghai. Instead of separated parts of speech decoding and language parsing, a close cool,ration is carded out in SHTQS by integrating automatic speech recognizer （AS,R）, language understanding, dialogue management and speech generatot. In such a way, the erroneous analysis and uncertainty happening in the preceding stages would be recovered and determined acourately with high-level knowledge, Moreover, instead of shallow word-level analysis or simply keyword or key phrase matching, a deeper analysis is performed in our system by integrating a robust parser and a semantic interpreter. The robust parser is particularly important for spontanecos speech inputs because most of the inquiry sentences/phrases are ill-formed. In addition, in designinga mixed-initiative dialogue system, understanding users＇ inquiries is essential; however, simply matching keywords and/or key phrases can hardly achieve this. Therefore, a semantic interpreter is incorporated in oar system. The performnce of is also evaluated. The dialogue efficiency is 4.4 sentences per query on an average and the case precision rate of language understanding module is up to 81%. The results are satisfactory.

关键词： spoken dialogue system ASR natural language understanding NLG TTS.

Highly Stereoselective Synthesis of 2,2-Disubstituted Vinylphosphonates via Aryl to Vinyl 1,4-Palladium Migration

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Chinese Journal of Chemistry 2022年第18期40卷 2188-2192页

作者： Yan-Zhen chen Geng-Yu Bao Xin-chen Zhan Jian-guo Fu Xiao-Ming Ji Shu-Sheng Zhang chen-guo feng The Research Center of Chiral Drugs Innovation Research Institute of Traditional Chinese MedicineShanghai University of Traditional Chinese MedicineShanghai201203 China

Vinylphosphates play an important role in the fields of synthetic chemistry,pharmaceuticals and material *** is a long-standing challenge to control the geometry of multi-substituted ***,an efficient method for the synthesis of 2,2-disubstituted vinylphosphonates has been *** reaction proceeded via aryl to vinyl 1,4-palladium migration progress,in which two difficulties that the deactivation of palladium catalyst by the coordination of excess secondary phosphine oxide and the competitive cross-coupling to form arylphosphonates are successfully *** judicious selection of phosphine ligand is the key to *** protocol features excellent regio-and stereoselectivitiy,generally excellent reaction yields and broad substrate socpe.

关键词： 1,4-Palladium migration Phosphorylation C-H activation Stereoselectivity Cross-coupling

Oxide formation on sputtered Ni-3Cr-10Al nanocrystalline coating

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中国有色金属学会会刊：英文版 2000年第3期10卷 397-400页

作者： chen guo feng(陈国锋) LOU Han yi(楼翰一) Chinese Acad Sci Inst Corros & Protect Met State Key Lab Corros & Protect Met Shenyang 110015 Peoples R China

The oxide formation on the sputtered Ni 3Cr 10Al nanocrystalline coating at 900 ℃ and 1 000 ℃ in air has been studied. The results indicated that an oxide scale composed of NiAl 2O 4 and Al 2O 3 was formed on the sputtered Ni 3Cr 10Al nanocrystalline coating whereas a unitary Al 2O 3 scale was not formed even when the Al content was high in the sputtered coating. The formation of NiAl 2O 4 was directly related to the precipitation of Ni 3Al in the coating during oxidation process. It was suggested that the precipitation of Ni 3Al contributed to the formation of NiO and therefore NiO could react with Al 2O 3 and form NiAl 2O 4. With increasing oxidation temperature, the effect of Ni 3Al precipitation on the formation of NiAl 2O 4 decreased.

关键词： Ni 3Cr 10Al sputtering nanocrystalline coating oxidation

Enzymatic Regioselective Synthesis of Vinyl Lactose Ester and Its Chemical Polymerization

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Chinese Chemical Letters 2002年第5期13卷 416-419页

作者： Qi WU Jian Yue feng chen guo feng De Shui LU Xian Fu LIN Department of Chemistry Zhejiang UniversityHangzhou 310027

Transesterification reaction of lactose with divinyladipate in pyridine catalyzed by an alkaline protease from Bacillus subtilis at 50C for 3 days gave 6-O-vinyladipoyl-lactose (yield 35%). Poly(6-O-vinyladipoyl-lactose) with Mn = 21,200, Mw = 32,900, Mw/Mn = 1.56 could be obtained by chemical polymerization. Poly(vinyl alcohol) containing lactose branch was biodegradable. After 6 days in aqueous buffer (PH 7), this alkaline protease could degrade the polymer to an Mn of ca. 2100, Mw/Mn = 2.56.

关键词： Regioselectivity vinyl ester lactose alkaline protease polymerization.

Improving the stability,lithium diffusion dynamics,and specific capacity of SrLi_(2)Ti_(6)O_(14)via ZrO_(2)coating

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Green Energy & Environment 2022年第1期7卷 53-65页

作者： Hong-Li Ding Hai-Tao Yu Xiao-dong Wang chen-feng guo Bing Zheng Ying Xie Ting-feng Yi Key Laboratory of Functional Inorganic Material Chemistry Ministry of EducationSchool of Chemistry and Materials ScienceHeilongjiang UniversityHarbin150080China College of Material Science and Chemical Engineering Harbin Engineering UniversityHarbin150001China School of Resources and Materials Northeastern University at QinhuangdaoQinhuangdao066004China Institute of Advanced Electrochemical Energy&School of Materials Science and Engineering Xi'an University of TechnologyXi'anShaanxi710048China

SrLi_(2)Ti_(6)O_(14)(SLTO)coated with different amount of ZrO_(2)was successfully *** as-obtained composites are stacked by a series of particles with a pure phase structure and a good ***,ZrO_(2)coating not only enhances the structural stability of the materials but also facilitates the diffusion of lithium through the SEI *** a result,the redox polarization was reduced,and the reversibility of the electrochemical reaction was ***,SLTO-ZrO_(2)-2 sample delivers a high initial lithiation capacity of 283.6 mA h g^(-1),and the values maintain at 251.7,228.0,207.4,175.3,and 147.7 mA h g^(-1)at the current densities of 0.13,0.26,0.54,1.31,and 2.62 A g^(-1),*** experiment also confirmed that SLTO materials coated with ZrO_(2)are suitable for high power density applications,and the lithiation specific energy efficiency of SLTO-ZrO_(2)-2 is 200%as high as that of pure SLTO at a power density of 1257 W kg^(-1).

关键词： SrLi_(2)Ti_(6)O_(14) ZrO_(2)coating Structural stability Anode material Electrochemical performance

DMMIC derivatization-assisted liquid chromatography-mass spectrometry method for metabolite profiling of the glutathione anabolic pathway in esophageal cancer tissues and cells

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Journal of Pharmaceutical Analysis 2023年第11期13卷 1365-1373页

作者： Li Liu Yu-Han Lu Min-Dan Wang Qun-Fei Zhao Xiu-Ping chen Hang Yin chen-guo feng Fang Zhang The Research Center of Chiral Drugs Shanghai Frontiers Science Center for TCM Chemical BiologyInnovation Research Institute of Traditional Chinese MedicineShanghai University of Traditional Chinese MedicineShanghai201203China Department of Thoracic Surgery Renji HospitalSchool of MedicineShanghai Jiaotong UniversityShanghai200127China School of Public Health Shanghai University of Traditional Chinese MedicineShanghai201203China

In this work,a new pyrylium derivatization-assisted liquid chromatography-mass spectrometry(LC-MS)method was developed for metabolite profiling of the glutathione anabolic pathway(GAP)in cancer tissues and *** pyrylium salt of 6,7-dimethoxy-3-methyl isochromenylium tetrafluoroborate(DMMIC)was used to label the amino group of metabolites,and a reductant of dithiothreitol(DTT)was employed to stabilize the thiol *** combining DMMIC derivatization with LC-MS,it was feasible to quantify the 13 main metabolites on the GAP in complex biological samples,which had good linearity(R^(2)=0.99810.9999),precision(interday precision of 1.6%e19.0%and intraday precision of 1.4%e19.8%)and accuracy(83.4%-115.7%).Moreover,the recovery assessments in tissues(82.5%e107.3%)and in cells(98.1%e118.9%)with GSH-^(13)C2,^(15)N,and Cys-^(15)N demonstrated the reliability of the method in detecting tissues and *** a methodological evaluation,the method was applied successfully to investigate difference in the GAP between the carcinoma and para-carcinoma tissues of esophageal squamous cell carcinoma(ESCC)and the effect of p-hydroxycinnamaldehyde(CMSP)on the GAP in KYSE150 esophageal cancer *** results demonstrate that the developed method provides a promising new tool to elucidate the roles of GAP in physiological and pathological processes,which can contribute to research on drugs and diseases.

关键词： Glutathione anabolic pathway Metabolite profiling DMMIC derivatization LC-MS Esophageal squamous cell carcinoma p-Hydroxycinnamaldehyde KYSE-150cell

Laser image refractive index sensor based on the combination of a coreless optical fiber and a digital camera

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Optoelectronics Letters 2025年第2期21卷 65-68页

作者： guo Jingzhong LAN feng chen Xiang LIU Haifeng Xi’an Institute of Space Radio Technology Xi’an 710100China Key Laboratory of Optoelectronic Sensor and Sensing Network Technology College of Electronic Information and Optical EngineeringNankai UniversityTianjin 300350China

As a laser passes through a scattering medium,the light interacts with the irregular reflections within the medium,resulting in light scattering and the formation of *** this paper,an image sensor based on the combination of a coreless optical fiber and a digital camera is proposed for liquid refractive index sensing *** coreless fiber is used as a sensing unit,and the change in the speckle pattern is measured using the digital correlation method to detect the magnitude of the liquid's refractive *** experimental results indicate that the laser image sensing technique is capable of effectively distinguishing liquid samples with refractive indices ranging from 1.332 8 to1.390 8,with a sensing sensitivity of-1.306 ***,the laser image sensing technique,with its advantages of high experimental reproducibility,simple system design,remote over-control,holds great research significance and potential application in laser communication and sensor integration.

关键词： fiber scattering optical

Protective effect of paeoniflorin on H_(2)O_(2) induced Schwann cells injury based on network pharmacology and experimental validation

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Chinese Journal of Natural Medicines 2021年第2期19卷 90-99页

作者： ZHANG Di YANG Bing CHANG Shi-Quan MA Sheng-Suo SUN Jian-Xin YI Lin LI Xing SHI Hui-Mei JING Bei ZHENG Ya-Chun ZHANG Chun-Lan chen feng-guo ZHAO guo-Ping College of Traditional Chinese Medicine Jinan UniversityGuangzhou 510630China LiWan Hospital of Traditional Chinese Medicine Guangzhou 510665China

This study was to investigate the protective effect of paeoniflorin(PF)on hydrogen peroxide-induced ***,“SMILES”of PF was searched in Pubchem and further was used for reverse molecular docking in Swiss Target Prediction database to obtain potential ***-related molecules were obtained from GeenCards database,and the predicted targets of PF for injury treatment were selected by Wayne *** mechanism analysis,the protein-protein interactions were constructed by String,and the KEGG analysis was conducted in ***,cell viability and cytotoxicity assay were established by CCK8 ***,the experimental cells were allocated to control,model(200μmol·L^(−1) H_(2)O_(2)),SB20358010μmol·L^(−1)(200μmol·L^(−1) H_(2)O_(2)+SB20358010μmol·L^(−1)),PF 50μmol·L^(−1)(200μmol·L^(−1) H_(2)O_(2)+PF 50μmol·L^(−1)),and PF 100μmol·L^(−1)(200μmol·L^(−1) H_(2)O_(2)+PF 100μmol·L^(−1))*** measured the intracellular ROS,Hoechst 33258 staining,cell apoptosis,the levels of Bcl-xl,Bcl-2,Caspase-3,Cleaved-caspase3,Cleaved-caspase7,TRPA1,TRPV1,and the phosphorylation expression of *** are 96 potential targets that may be associated with PF for injury ***,we chose the“Inflammatory mediator regulation of TRP channels”pathway for the experimental verification from the first 10 KEGG *** experimental verification,H_(2)O_(2) decreased the cell viability moderately(P<0.05),and 100μmol·L^(−1) PF increased the cell viability significantly(P<0.05).Depending on the difference of intracellular ROS fluorescence intensity,PF inhibited H_(2)O_(2)-induced reactive oxygen species production in Schwann *** Hoechst 33258 staining,PF reversed the condensed chromatin and apoptotic nuclei following H_(2)O_(2) ***,Flow cytometry results showed that PF could substantially inhibit H_(2)O_(2) induced apoptosis(P<0.05).Pretreatment with PF obviously reduced the levels of Caspase3,Cleaved-caspase3,Cleaved-caspase7,TRPA1,TRPV1,and the pho

关键词： Paeoniflorin Hydrogen peroxide H_(2)O_(2) p38MAPK Schwann cells Network pharmacology