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Organic Chemistry Frontiers 2022年第4期9卷 1143-1151页

作者： Xiahe Chen Chaoqin Cao Yun-Fang Yang yuan-bin she College of Chemical Engineering Zhejiang University of TechnologyHangzhouZhejiang 310014China

The mechanisms and regioselectivities of the Ir-porphyrin-catalyzed C–H insertion reaction of quinoid carbene(QC)were investigated by density functional theory(DFT)*** competing catalytic cycles were identified as the hydrogen-atom abstraction by quinoid oxygen(HAA-O)and hydrogen-atom abstraction by carbene carbon(HAA-C)catalytic cycles.

关键词： porphyrin insertion catalyzed

Rapid recognition of Chinese herbal pieces of Areca catechu by different concocted processes using Fourier transform mid-infrared and near-infrared spectroscopy combined with partial least-squares discriminant analysis

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Chinese Chemical Letters 2013年第7期24卷 639-642页

作者： Hai-Yan Fu Dong-Chen Huang Tian-Ming Yang yuan-bin she Hao Zhang Third Class Laboratory About Ethno-medicine of State Administration of Traditional Chinese Medicine College of PharmacySouth-Central University for Nationalities Key Laboratory of Catalysis and Materials Science of the State Ethnic Affairs Commission & Ministry of Education.College of Chemistry and Materials Science South-Central University for Nationalities Third Class Laboratory About Ethno-medicine of State Administration of Traditional Chinese Medicine College of Pharmacy.South-Central University for Nationalities

Rapid and sensitive recognition of herbal pieces according to different concocted processing is crucial to quality control and pharmaceutical effect. Near-infrared （NIR） and mid-infrared （MIR） technology combined with supervised pattern recognition based on partial least-squares discriminant analysis （PLSDA） was attempted to classify and recognize six different concocted processing pieces of 600 Areca catechu L. samples and the influence of fingerprint information preprocessing methods on recognition performance was also investigated in this work. Recognition rates of 99.24%, 100% and 99.49% for original fingerprint, multiple scatter correct （MSC） fingerprint and second derivative （2nd derivative） fingerprint of NIR spectra were achieved by PLSDA models, respectively. Meanwhile, a perfect recognition rate of 100% was obtained for the above three fingerprint models of MIR spectra. In conclusion, PLSDA can rapidly and effectively extract otherness of fingerprint information from NIR and MIR spectra to identify different concocted herbal pieces ofA. catechu.

关键词： NIR and MIR spectroscopy Partial least-squares discriminant analysis Different concocted processing herbal pieces

Characterization of Aroma-Active Components and Antioxidant Activity Analysis of E-jiao(Colla CoriiAsini)from Different Geographical Origins

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Natural Products and Bioprospecting 2018年第2期8卷 71-82页

作者： Shan Zhang Lu Xu Yang-Xi Liu Hai-Yan Fu Zuo-bing Xiao yuan-bin she State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology College of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014China College of Material and Chemical Engineering Tongren UniversityTongren 554300GuizhouChina School of Pharmaceutical Sciences South-Central University for NationalitiesWuhan 430074China School of Perfume and Aroma Technology Shanghai Institute of TechnologyShanghai 201418China

E-jiao(Colla Corii Asini,CCA)has been widely used as a healthy food and Chinese *** authentic CCA is characterized by its typical sweet and neutral fragrance,its aroma components have been rarely *** work investigated the aroma-active components and antioxidant activity of 19 CCAs from different geographical *** extracts obtained by simultaneous distillation and extraction were analyzed by gas chromatography-mass spectrometry(GC-MS),gas chromatography-olfactometry(GC-O)and sensory *** antioxidant activity of CCAs was determined by ABTS and DPPH assays.A total of 65 volatile compounds were identified and quantified by GC-MS and 23 aroma-active compounds were identified by GC-O and aroma extract dilution *** most powerful aroma-active compounds were identified based on the flavor dilution factor and their contents were compared among the 19 *** component analysis of the 23 aroma-active components showed 3 significant *** correlation analysis between antioxidant assays and the 23 aroma-active compounds indicates strong correlation(r=0.9776,p=0.0281).Analysis of aroma-active components shows potential for quality evaluation and discrimination of CCAs from different geographical origins.

关键词： Colla Corii Asini Aroma-active compounds Antioxidant activity Chemometrics

Resistance of Cement-based Grouting Materials with Nano- SiO_(2) Emulsion to Chloride Ion Penetration

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 114-119页

作者： LI Shuiping CHENG Jian WEI Chao yuan bin YU Chengxiao College of Architectural Science and Engineering Yangzhou UniversityYangzhou 225127China

The chloride penetration resistance of cement-based grout materials was improved by nano-silica *** of mixtures containing different nano-silica particles or emulsions were exposed in sodium chloride solutions of specific concentrations with different test *** properties of the mixes were assessed in terms of weight loss and compressive strength.X-ray diffraction(XRD)and scanning electron microscopy(SEM)of mixes were performed to analysis the phase evolution and *** results demonstrated that the introduction of nano-SiO_(2) emulsion significantly decreased the compressive strength loss and calcium hydroxide(CH)crystal content of hydration production,and then enhanced the resistance of cement-based grouting materials to chloride ion *** improvement derives from the filling and pozzolanic effects of nano-SiO_(2) particles,which were incorporated via an emulsion and attributed to a well dispersion in grouting matrix.

关键词： grouting materials nano-SiO_(2)emulsion chloride ion penetration,weight loss strength loss

A promising approach for quantifying focal stroke modeling and assessing stroke progression:optical resolution photoacoustic microscopy photothrombosis

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Neural Regeneration Research 2025年第7期20卷 2029-2037页

作者： Xiao Liang Xingping Quan Xiaorui Geng Yujing Huang Yonghua Zhao Lei Xi Zhen yuan Ping Wang bin Liu Faculty of Health Sciences University of MacaoMacao Special Administrative RegionChina Center for Cognitive and Brain Sciences University of MacaoMacao Special Administrative RegionChina Department of Biomedical Engineering Southern University of Science and TechnologyShenzhenGuangdong ProvinceChina State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoTaipaMacao Special Administrative RegionChina Department of Emergency Zhujiang HospitalSouthern Medical UniversityGuangzhouGuangdong ProvinceChina

To investigate the mechanisms underlying the onset and progression of ischemic stroke,some methods have been proposed that can simultaneously monitor and create embolisms in the animal cerebral ***,these methods often require complex systems and the effect of age on cerebral embolism has not been adequately studied,although ischemic stroke is strongly *** this study,we propose an optical-resolution photoacoustic microscopy-based visualized photothrombosis methodology to create and monitor ischemic stroke in mice simultaneously using a 532 nm pulsed *** observed the molding process in mice of different ages and presented age-dependent vascular embolism ***,we integrated optical coherence tomography angiography to investigate age-associated trends in cerebrovascular variability following a *** imaging data and quantitative analyses underscore the differential cerebrovascular responses to stroke in mice of different ages,thereby highlighting the technique's potential for evaluating cerebrovascular health and unraveling age-related mechanisms involved in ischemic strokes.

关键词： age-dependent cerebral cortex ischemic stroke mouse model optical coherence tomography angiography photoacoustic microscopy photothrombosis vascular imaging

High-dose dexamethasone regulates microglial polarization via the GR/JAK1/STAT3 signaling pathway after traumatic brain injury

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Neural Regeneration Research 2025年第9期20卷 2611-2623页

作者： Mengshi Yang Miao Bai yuan Zhuang shenghua Lu Qianqian Ge Hao Li Yu Deng Hongbin Wu Xiaojian Xu Fei Niu Xinlong Dong bin Zhang Baiyun Liu Beijing Tiantan Hospital Capital Medical UniversityBeijingChina Department of Neurology The First Hospital of Tsinghua UniversityBeijingChina Department of Neurotrauma and Beijing Key Laboratory of Central Nervous System Injury Beijing Neurosurgical InstituteCapital Medical UniversityBeijingChina Department of Critical Care Medicine Beijing Tiantan HospitalCapital Medical UniversityBeijingChina Center for Nerve Injury and Repair Beijing Institute of Brain DisordersChina National Clinical Research Center for Neurological DiseasesBeijingChina

Although microglial polarization and neuroinflammation are crucial cellular responses after traumatic brain injury,the fundamental regulatory and functional mechanisms remain insufficiently *** potent anti-inflammato ry agents,the use of glucoco rticoids in traumatic brain injury is still controversial,and their regulatory effects on microglial polarization are not yet *** the present study,we sought to determine whether exacerbation of traumatic brain injury caused by high-dose dexamethasone is related to its regulatory effects on microglial polarization and its mechanisms of *** vitro cultured BV2 cells and primary microglia and a controlled cortical impact mouse model were used to investigate the effects of dexamethasone on microglial ***,dexamethasone,RU486(a glucocorticoid receptor antagonist),and ruxolitinib(a Janus kinase 1 antagonist)were ***-sequencing data obtained from a C57BL/6 mouse model of traumatic brain injury were used to identify potential targets of *** Morris water maze,quantitative reverse transcription-polymerase chain reaction,western blotting,immunofluorescence and confocal microscopy analysis,and TUNEL,Nissl,and Golgi staining were performed to investigate our ***-throughput sequencing results showed that arginase 1,a marker of M2 microglia,was significantly downregulated in the dexamethasone group compared with the traumatic brain injury group at3 days post-traumatic brain *** dexamethasone inhibited M1 and M2 microglia,with a more pronounced inhibitory effect on M2microglia in vitro and in *** receptor plays an indispensable role in microglial polarization after dexamethasone treatment following traumatic brain ***,glucocorticoid receptor activation increased the number of apoptotic cells and neuronal death,and also decreased the density of dendritic spines.A possible downstream receptor signaling mechanism is th

关键词： apoptosis BV2 microglia dexamethasone glucocorticoid receptor glucocorticoids innate immune system microglial polarization neuroinflammation primary microglia traumatic brain injury

Difference in microstructural characteristics of stamp-charged coke and gravity-charged coke with approximate macroscopic performance

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Journal of Iron and Steel Research International 2024年第5期31卷 1050-1062页

作者： Chong Zou Zheng-yan Huang Jian-yun Li bin Li Shi-wei Liu yuan she School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710311ShaanxiChina Technical Center of Shandong Iron and Steel Co. Ltd.(Laiwu Branch)Jinan271104ShandongChina

The microstructural characteristics including optical texture,porosity and pore structure and chemical structure of stamp-charged coke(SCC)and gravity-charged coke(GCC)with similar conventional macro-indicators were investigated,and the properties including micro-strength,reactivity of coke matrix and that after alkali enrichment were comparatively studied by various characterization *** anisotropic structure of SCC is composed of high content of fine mosaic texture,while the content of medium mosaic texture,coarse texture and fibrous texture is *** statistical average shows that the fine mosaic average of SCC(24.89%)is 3.78 times the GCC average(6.58%),and the coarse mosaic average(1.24%)is only about 1/3 of the GCC average(3.43%).The porosity of SCC is lower than that of GCC,but tamping process does not lead to the fact that the number of closed pores of SCC is significantly lower than that of *** the structure of SCC is compact,its pore number is large and the pore wall is *** of coke with diameter less than 150 nm seem unaffected by tamping *** aromatic structure of SCC was less ordered than that of GCC,which was speculated to be related to the addition of more low metamorphic coal in *** microscopic strength and structural strength of SCC are lower than those of *** reactivity of coke matrix is affected by the specific surface area,but it is not the determining factor of its *** improvement in dissolution reactivity of coke after potassium enrichment is independent of coke type.

关键词： Stamp-charged coke Optical texture Porosity Microstructure Reactivity

Resistance of Cement-based Grouting Materials with Nano-SiO2 Emulsion to Chloride Ion Penetration

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期 114-119页

作者：黎水平 CHENG Jian WEI Chao yuan bin YU Chengxiao College of Architectural Science and Engineering Yangzhou University

The chloride penetration resistance of cement-based grout materials was improved by nano-silica *** of mixtures containing different nano-silica particles or emulsions were exposed in sodium chloride solutions of specific concentrations with different test *** properties of the mixes were assessed in terms of weight loss and compressive strength.X-ray diffraction （XRD） and scanning electron microscopy （SEM） of mixes were performed to analysis the phase evolution and *** results demonstrated that the introduction of nano-SiO2emulsion significantly decreased the compressive strength loss and calcium hydroxide （CH） crystal content of hydration production,and then enhanced the resistance of cement-based grouting materials to chloride ion *** improvement derives from the filling and pozzolanic effects of nano-SiO2particles,which were incorporated via an emulsion and attributed to a well dispersion in grouting matrix.

关键词：

Two performance enhanced control of flexible-link manipulator with system uncertainty and disturbances

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Science China(Information Sciences) 2017年第5期60卷 25-35页

作者： bin XU yuan yuan School of Automation Northwestern Polytechnical University School of Automation Science and Electrical Engineering Beihang University

Precision control of flexible-link manipulator for space operation is challenging due to the dynamics coupling and system uncertainty. In this paper, to deal with system uncertainty and time-varying disturbance,two performance enhanced controller designs, named Composite Learning Control and Disturbance Observer Based Control are presented respectively. To overcome the nonminimum phase, using output redefinition, the dynamics is transformed to two subsystems: internal system and input-output system. For the internal dynamics,the PD(proportion differentiation) control is used with pole assignment. For the input-output subsystem,considering the unknown dynamics, the composite learning control is designed using neural modeling error while in case of disturbance, the disturbance observer based design is proposed. The stability analysis of the closed-loop system is presented via Lyapunov approach. Simulation of 2-degrees of freedom(DOF) flexible-link manipulator is conducted and the results show that the proposed methods can enhance the tracking performance.

关键词： flexible-link manipulator composite learning control disturbance observer output redefinition system uncertainty

Fabrication and Life Prediction of SSiC Ceramic Joint Joined with Silicon Resin YR3370

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Chinese Journal of Aeronautics 2007年第1期20卷 81-85页

作者： yuan Xiao-kun XU bing-she School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China College of Materials Science and Engineering Taiyuan University of Technology Taiyuan 030024 China

Joints between sintered silicon carbide （SSiC） were produced using a polysiloxane silicon resin YR3370 （GE Toshiba Silicones） as joining material. Samples were heat treated in a 99.99% nitrogen flux at temperatures ranging from 1 100 ℃ to 1 300 ℃. Three point bending strength of the joint reached the maximum of 179 MPa as joined at 1 200℃. The joining layer is continuous, homogeneous and densified and has a thickness of 2 μm -5μm. The joining mechanism is that the amorphous silicon oxycarbide （SixOyCz） ceramic pyrolyzed from silicon resin YR3370 acts as an inorganic adhesive to SSiC substrate, which means the formation of the continuous Si-C bond structure between SixOyCz structure and SSiC substrate. Life prediction of the ceramic joint can be realized through the measurement of the critical time of the joint after the cyclic loading test.

关键词： silicon resin YR3370 SiC ceramic ceramic joining joint life