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Two new flavonoid diglycosides from Cephalotaxus sinensis

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Chinese Chemical Letters 2007年第7期18卷 837-839页

作者： Wei li Rong Ji Dai yu Hong yu liang li Wei Wei Meng yu lin Deng School of life Science and Technology Beijing Institute of Technology Beijing 100081 China

Two new acetylated flavonoid diglycosides, scutellarein-5-O-[α-L-rhamnopyranosyl-（1 → 4）-β-D-6-O-acetylglucopyranoside]（1）, apigenin-5-O-[α-L-rhamnopyranosyl-（1→ 2）-β-D-3,6-di-O-acetylglucopyranoside] （2）, were isolated from the leaves of Cephalotaxus sinensis. Their structures were determined by chemical and spectroscopic methods including HR-FAB-MS,^1H-^1H COSY, HSQC and HMBC experiments.

关键词： Cephalotaxus sinensis (Rehd et Wile) li Flavonoid diglycosides Scutellarein-5-O-[α-L-rhamnopyranosyl-(1→ 4)-β-D-6-O-acetylglucopyranoside] Apigenin-5-O-[α-L-rhamnopyranosyl-(1 → 2)-β-D-3,6-di-O-acetylglucopyranoside]

Tensile Properties of TWIP Steel at High Strain Rate

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Journal of Iron and Steel Research International 2009年第1期16卷 81-86,21页

作者： XIONG Rong-gang FU Ren-yu SU yu li Qian WEI Xi-cheng li lin School of Materials Science and Engineering Shanghai University Shanghai 200072 China

Tensile tests of TWIP steels of two compositions are performed in the strain rate range of 10^-5-10^3 s^-1. Results indicate that steel 1^# does not exhibit TWIP effect but deformation-induced martensitic transformation appears only. There exists TWIP effect in steel 3^# . Tensile properties at room temperature are sensitive to strain rate in the studied strain rate ranges. Analysis on the relationship between strain-hardening exponent and strain rates shows that strain induced martensitic transformation and formation of twins during deformation have significant in- fluence on their strain-hardening behavior.

关键词： twin-induced plasticity strain rate strain hardening deformation twin

Re-expression of DIRAS3 and P53 induces apoptosis and impaired autophagy in head and neck squamous cell carcinoma

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Military Medical Research 2021年第2期8卷 148-161页

作者： Zhe liu Douglas R.Hurst Xing Qu li-Guang Lu Chen-Zhou Wu yu-yu li Yi li State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases West China Hospital of StomatologySichuan UniversityChengdu 610041China Department of Head and Neck Oncology West China Hospital of StomatologySichuan UniversityChengdu 610041China Department of Pathology University of Alabama at BirminghamBirminghamAL 35216USA Department of Evidence Based Stomatology West China Hospital of StomatologySichuan UniversityChengdu 610041China.

Background:p53 and DIRAS3 are tumor suppressors that are frequently silenced in *** this study,we sought to determine whether the concurrent re-expression of p53 and DIRAS3 could effectively induce head and neck squamous cell carcinoma(HNSCC)cell ***:CAL-27 and SCC-25 cells were treated with Ad-DIRAS3 and rAd-p53 to induce re-expression of DIRAS3 and p53 *** effects of DIRAS3 and p53 re-expression on the growth and apoptosis of HNSCC cells were examined by TUNEL assay,flow cytometric analysis and *** effects of DIRAS3 and p53 re-expression on Akt phosphorylation,oncogene expression,and the interaction of 4 E-BP1 with eIF4 E were determined by real-time PCR,Western blotting and immunoprecipitation *** ability of DIRAS3 and p53 re-expression to induce autophagy was evaluated by transmission electron microscopy,LC3 fluorescence microscopy and Western *** effects of DIRAS3 and p53 re-expression on HNSCC growth were evaluated by using an orthotopic xenograft mouse ***:TUNEL assay and flow cytometric analysis showed that the concurrent re-expression of DIRAS3 and p53 significantly induced apoptosis(Pliferation and induced cell cycle arrest(Plin D1,vascular endothelial growth factor(VEGF),fibroblast growth factor(FGF),epidermal growth factor receptor(EGFR)and Bcl-2(P<0.001).Moreover,the concurrent re-expression of DIRAS3 and p53 increased the percentage of cells with GFP-LC3 puncta compared with that in cells treated with control adenovirus(50.00%±4.55%vs.4.67%±1.25%,P<

关键词： DIRAS3 p53 Apoptosis Autophagy Head and neck squamous cell carcinoma

Reversible li plating regulation on graphite anode through a barium sulfate nanofibers-based dielectric separator for fast charging and high-safety lithium-ion battery

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Journal of Energy Chemistry 2025年第2期101卷 511-523页

作者： Yaxin Zhang Long Cheng Ying-Jie Zhu Jin Wu Han-Ping yu Sida Xie Dandan li Zhaohui Wang Heng li State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of Sciences College of Materials Science and Engineering Hunan University Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences

Poor li plating reversibility and high thermal runaway risks are key challenges for fast charging lithiumion batteries with graphite ***,a dielectric and fire-resistant separator based on hybrid nanofibers of barium sulfate（BS） and bacterial cellulose（BC） is developed to synchronously enhance the battery's fast charging and thermal-safety *** regulation mechanism of the dielectric BS/BC separator in enhancing the li+ion transport and li plating reversibility is revealed.（1） The Max-Wagner polarization electric field of the dielectric BS/BC separator can accelerate the desolvation of solvated li+ions,enhancing their transport kinetics.（2） Moreover,due to the charge balancing effect,the dielectric BS/BC separator homogenizes the electric field/li+ion flux at the graphite anode-separator interface,facilitating uniform li plating and suppressing li dendrite ***,the fast-charge graphite anode with the BS/BC separator shows higher Coulombic efficiency（99.0% vs.96.9%） and longer cycling lifespan（100 cycles vs.59 cycles） than that with the polypropylene（PP） separator in the constantlithiation cycling test at 2 mA *** high-loading liFePO4(15.5 mg cm-2)//graphite(7.5 mg cm-2) full cell with the BS/BC separator exhibits excellent fast charging performance,retaining 70% of its capacity after 500 cycles at a high rate of 2C,which is significantly better than that of the cell with the PP separator（retaining only 27% of its capacity after 500 cycles）.More importantly,the thermally stable BS/BC separator effectively elevates the critical temperature and reduces the heat release rate during thermal runaway,thereby significantly enhancing the battery's safety.

关键词： Fast charging Graphite anode Ion transport lithium-ion battery Separator

Reversible li2C2O4 product regulation in li–CO2 batteries using single-atom alloy engineering

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Science China Chemistry 2025年

作者： Xinxin Zhang yu Wang Yafei li Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Centre of Biomedical Functional Materials School of Chemistry and Materials Science Nanjing Normal University

The efficiency of lithium-carbon dioxide （li–CO2） batteries is limited by the sluggish generation/decomposition kinetics of the discharge products （i.e.,li2CO3and carbon） despite the use of state-of-the-art noble metal （NM） ***2C2O4has emerged as a promising alternative product;however,the thermodynamic instability of li2C2O4causes it to generally appear as an intermediate in li2CO3pathways rather than a product during ***,using comprehensive first-principles calculations,we report tailoring the discharge products of li–CO2batteries to li2C2O4via single-atom alloy （SAA） engineering,in which NM-doped copper SAAs （NM1Cu） are constructed for *** NM1Cu catalysts display a free-atom-like narrow d-band state and unique charge distribution over the solute NM1atom and the surrounding matrix Cu *** an optimized electronic structure is substantial in Ru1Cu and Ir1Cu,which is conducive to the co-activation and coupling of *** lithiation of*CO2intermediate that breaks the charge symmetry of the central C species can further reduce the kinetic barriers of the C–C *** advantages promote li2C2O4generation on Ru1Cu and Ir1Cu while suppress its subsequent ***,they exhibit low theoretical overpotentials and enable facile delithiation under normal charging *** work proposes a universal principle of manipulating electronic structures to achieve li2C2O4product,which provides practical guidance for the development of li–CO2batteries.

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Upper Bounds on the Multicolor Ramsey Numbers r_(k)(C_(4))

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 286-294页

作者： Tian-yu li Qi-zhong liN Center for Discrete Mathematics Fuzhou UniversityFuzhou 350108China

The multicolor Ramsey number r_(k)(C_(4))is the smallest integer N such that any k-edge coloring of KN contains a monochromatic C_(4).The current best upper bound of r_(k)(C_(4))was obtained by Chung(1974)and independently by Irving(1974),i.e.,r_(k)(C_(4))≤k^(2)+k+1 for all k≥*** is no progress on the upper bound since *** this paper,we improve the upper bound of r_(k)(C_(4))by showing that r_(k)(C_(4))≤k^(2)+k-1 for even k≥*** improvement is based on the upper bound of the Turan number ex(n,C4),in which we mainly use the double counting method and many novel ideas from Firke,Kosek,Nash,and Williford[***,Ser.B 103(2013),327-336].

关键词： Multicolor Ramsey number Turan number 4-cycle

EVALUATION OF ADHESION AND PLASTICITY OF PVD FILMS

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Acta Metallurgica Sinica(English Letters) 1992年第11期5卷 411-416页

作者： liU Changqing JIN Zhujing yu li yu Zhiming WU Weitao Corrosion Science Laboratory,Institute of corrosion and Protection of Metals,Academia Sinica,Shenyang,China Inst of Corrosion and Protection of Metals Academia Sinica Shenyang China

Evaluation of adhesion of PVD Ti and TiN films on steel A_3 was carried out with constant rate pulling test(CRPT)at 0.05 mm/min under simultaneous SEM observation. As a criterion,the critical elongations of the film/substrate system for the initial cracking and spelling of the film may be applied to evaluate the plasticity and adhesion of the film to *** conventional scratch test was also made for evaluation of the adhesion for the same *** methods give the coordinate assessment for all the systems. In addition,the influence of the films on the ultimate yield strength of the substrate was discussed and another criterion of conherent work was proposed for the evaluation.

关键词： PVD film constant rate pulling test scratch test adhesion

Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 39-48页

作者： Peng li Meifeng Cai Shengjun Miao yuan li yu Wang Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and TechnologyXuzhou 221116China

Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress *** investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution *** results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with *** is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and ***,there is no obvious relationship between the rock quality designation(RQD)and *** maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same *** addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data.

关键词： overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification

Impulsive Consensus of MASs With Input Saturation and DoS Attacks

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 414-424页

作者： Xuyang Wang Dengxiu yu Xiaodi li the Unmanned System Research Institute Northwestern Polytechnical University IEEE the School of Artificial Intelligence Optics and Electronics Northwestern Polytechnical University the School of Mathematics and Statistics Shandong Normal University the Center for Control and Engineering Computation Shandong Normal University

This paper investigates the secure impulsive consensus of lipschitz-type nonlinear multi-agent systems(MASs) with input saturation. According to the coupling of input saturation and denial of service(DoS) attacks, impulsive control for MASs becomes extremely challenging. Considering general DoS attacks,this paper provides the sufficient conditions for the almost sure consensus of the MASs with input saturation, where the error system can achieve almost sure local exponential *** linear matrix inequalities(LMIs), the relation between the trajectory boundary and DoS attacks is characterized, and the trajectory boundary is estimated. Furthermore, an optimization method of the domain of attraction is proposed to maximize the size. And a non-conservative and practical boundary is proposed to characterize the effect of DoS attacks on MASs. Finally, considering a multi-agent system with typical Chua's circuit dynamic model, an example is provided to illustrate the theorems' correctness.

关键词： Almost sure consensus denial of service (DoS) attacks impulsive control input saturation