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SYNTHESIS AND CHARACTERIZATION OF WATER-SOLUBLE CdSe NANOPARTICLES CAPPED BY AOT

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Chinese Journal of Polymer Science 2013年第9期31卷 1284-1289页

作者： yan-ming chen Xiao-bo Nie School of Petrochemical Engineering Shenyang University of Technology

Water-soluble CdSe nanoparticles were synthesized using AOT （sodium bis（2-ethylehexyl）-sulfosuccinate） as stabilizer, cadmium acetate and NazSeSO3 as precursors in aqueous phase. The influence of some key factors, such as reaction time, temperature, concentration and molar ratio of precursors on the optical properties of CdSe nanoparticles was systematically investigated through UV-Vis and PL spectra. Powder X-ray diffraction （XRD） was used to characterize the crystalline structure of synthesized CdSe nanoparticles. As-prepared CdSe nanoparticles exhibit an apparent quantum confinement effect and typical hexagonal wurtzite structures. Finally, the optimal experimental conditions were obtained.

关键词： AOT CdSe Nanoparticles Aqueous phase.

Non-constant Stationary Solutions to a Prey-predator Model with Diffusion

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Acta Mathematicae Applicatae Sinica 2009年第1期25卷 141-150页

作者： ming yang Wen-yan chen Department of Mathematics Southeast University Nanjing 210096 China

In this paper, a nonlinear predator reproduction and prey competition model with diffusion is discussed. Some existence and non-existence results concerning non-constant positive steady-states are presented using topo... 详细信息

关键词： Prey-predator model steady states degree method energy method

Weak Cartan-type Second Main Theorem for Holomorphic Curves

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Acta Mathematica Sinica,English Series 2008年第3期24卷 455-462页

作者： Qi ming yan Zhi Hua chen Department of Mathematics Tongji University Shanghai 200092 P. R. China

In this paper, a weak Cartan-type second theorem for holomorphic curve f ： C→P^n（C） intersecting hypersurfaces Dj, 1≤j≤q, in P^n（C） in general position with degree dj is given as follows： For every ε〉0, there exists a positive integer M such that ｜｜（q - （n ＋ 1） ε）Tf（r）≤∑j^q=1 1/dj Nf^M（r,Dj）＋o（Tf（r））, where ＂｜｜＂ means the estimate holds for all large r outside a set of finite Lebesgue measure.

关键词： holomorphic curve Nevanlinna Theory second main theorem hypersurface

Effect of ATF3-deletion on apoptosis of cultured retinal ganglion cells

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International Journal of Ophthalmology(English edition) 2017年第5期10卷 691-695页

作者： ming-ming Sun Ya-chen Wang Yi Li Xiao-Dan Guo yan-ming chen Zhong-Zhi Zhang Ophthalmology Department the First Hospital of China Medical University Shenyang 110001 Liaoning ProvinceChina

AIM：To investigate the effect of activating transcription factor-3（ATF3）-deletion on apoptosis of cultured retinal ganglion cells（RGCs）.METHODS：Three ATF3 siR NA（ATF3-rat-651, ATF3-rat-319, ATF3-rat-520） were constructed, and were transiently transfected into RGC-5 cells. Quantitative real-time polymerase chain reaction（PCR） was used to examine ATF3 expression and the most effective ATF3 siR NA was selected for further studies. Flow cytometry was applied to investigate the effects of ATF3 deletion on RGC-5 apoptosis under elevated hydrostatic pressure. Quantitative realtime PCR and Western blot were performed to validate differentially expressed genes and proteins in ATF3-knockdown RGC-5 ***：ATF3 specific siR NA effectively down-regulated ATF3 expression and significantly inhibited cell apoptosis in RGC-5 cells. Quantitative real-time PCR and Western blot confirmed that ATF3 knockdown remarkably decreased Jun-B and increased c-Jun at both m RNA and protein levels in RGC-5 ***：ATF/cA MP-response element-binding family of transcription factors may be involved in the development of glaucoma and could be novel treatment targets for glaucoma.

关键词： ATF3 elevated hydrostatic pressure apoptosis glaucoma

Prevalence and characteristics of dyspepsia among college students in Zhejiang Province

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World Journal of Gastroenterology 2014年第13期20卷 3649-3654页

作者： Meng Li Bin Lu Li Chu Hong Zhou ming-yan chen Depart- ment of Gastroenterology First Affiliated Hospital of Zhejiang Chinese Medical University

AIM: To investigate the prevalence and characteristics of uninvestigated dyspepsia among college students in Zhejiang Province.

关键词： College student Dyspepsia Gastroesophageal Irritable bowel syndrome

Effect of H_2 dilution on the structure and properties of nc-CrC/a-C:H coatings deposited by a hybrid beams system

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Nuclear Science and Techniques 2018年第1期29卷 118-126页

作者： Yao Cai Hui-Dong Liu Zhong-Wei Hu Qiang Wan Chang Luo Hao chen yan Liu yan-ming chen Qing-Song Mei Bing yang School of Power and Mechanical Engineering Wuhan University School of Materials Science and Engineering Xi'an Jiao Tong University China Datang Corporation Science and Technology Research Institute Co. Ltd. East China Branch

Nanocomposite Cr C/hydrogenated amorphous carbon(nc-CrC/a-C:H) coatings were deposited by a hybrid beams system comprised of a hollow cathode ion source and a cathodic arc ion-plating unit with varying H_2 flow rates. The influences of H_2 flow rates on the morphologies, microstructures, and properties of the coatings were systematically studied. The morphologies and microstructures of the coatings were characterized by SEM, AFM, XPS, Raman spectroscopy, GIXRD, and HRTEM. The mechanical and tribological properties were measured by a nano-indenter, scratch tester, and ball-ondisk tribometer. The wear tracks were evaluated using 3D profilometer, optical microscope, and EDS analysis. It has been found that a moderate H_2 flow rate can effectively smooth the surface, enlarge the fraction of a sp^3 bond, and improve the properties. The coating exhibits the highest hardness and elastic modulus at the H_2 flow rate of 40 sccm. A superior combination of adhesion strength,friction coefficient, and wear resistance can be achieved at the H_2 flow rate of 80 sccm.

关键词： CrC/a-C:H coating Nanocomposite H2 flow rate Hybrid beams system

Three novel dendritic chitosan derivatives for inhibiting acid corrosion of petroleum pipelines

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Petroleum Science 2023年第6期20卷 3918-3930页

作者： Guo-Dong Cui yan-ming chen Qi-ming Zhang Zheng Wang Tian Tang Qing Zhao Yu Zhang Li-Feng Zhang Yuan-Qi Gu yang-Sheng Liu College of Environmental Sciences and Engineering Peking UniversityBeijing Key Laboratory for Solid Waste Utilization and ManagementBeijing100871China University of Houston HoustonTX77204United States State Key Laboratory of Heavy Oil Processing College of ScienceChina University of PetroleumBeijing102249China CenerTech Tianjin Chemical Research and Design Institute Co. LtdChina National Offshore Oil Corp(CNOOC)Tianjin300131China Faculty of Environment and Life Beijing University of TechnologyBeijing100124China Shanxi International Energy Group Co. LtdTaiyuan030002ShanxiChina

In the process of exploration and development of oil and gas fields, the acidic environment of oil reservoir, production and transport processes cause corrosion of pipelines and equipment, resulting in huge economic losses and production safety risks. Corrosion inhibitors were widely used in oil industry because of simple operation process and economical. In this study, three environmentally friendly corrosion inhibitors were synthesized based on the natural polysaccharide chitosan. Corrosion inhibition of three dendritic chitosan derivatives (We name them BH, CH and DH) on mild steel in 1 mol/L HCl solution with natural ventilation system was evaluated by weight loss experiment, electrochemical analysis and surface morphology characterization. The experimental results showed that when the three dendritic chitosan derivatives added in the corrosive medium were 500 mg L^(−1), the corrosion inhibition efficiencies were all more than 80%. Based on quantum chemical calculation, inhibition mechanisms of three dendritic chitosan derivatives were investigated according to molecular structures. The results showed that the benzene ring, Schiff base and N atom contained in the molecule were the active centers of electron exchange, which were more likely to form a film on the carbon steel surface, thereby slowing or inhibiting corrosion. The results also predicted the corrosion inhibition effect BH > DH > CH, which was consistent with the experimental conclusion.

关键词： Chitosan derivatives Corrosion inhibitors Carbon steel Acid inhibition Efficient and environmental

Focal mechanics and disaster characteristics of the 2024 M 7.6 Noto Peninsula Earthquake,Japan

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Frontiers of Structural and Civil Engineering 2024年第9期18卷 1378-1387页

作者： Guang-qi chen yan-qiang WU ming-yao XIA Zhi-yuan LI School of Civil and Transportation Engineering Hebei University of TechnologyTianjin 300131China Graduate School of Engineering Kyushu UniversityFukuoka 819-0395Japan The First Monitoring and Application Center China Earthquake AdministrationTianjin 300180China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China

On January 1,2024,a devastating M 7.6 earthquake struck the Noto Peninsula,Ishikawa Prefecture,Japan,resulting in significant casualties and property *** information from the first six days after the earthquake,this article analyzes the seismic source characteristics,disaster situation,and emergency response of this *** results show:1)The earthquake rupture was of the thrust type,with aftershock distribution showing a north-east-oriented belt-like feature of 150 km.2)Global Navigation Satellite System(GNSS)and Interferometric synthetic aperture radar(InSAR),observations detected significant westward to north-westward co-seismic displacement near the epicenter,with the maximum horizontal displacement reaching 1.2 m and the vertical uplift displacement reaching 4 m.A two-segment fault inversion model fits the observational data well.3)Near the epicenter,large Peak Ground Velocity(PGV)and Peak Ground Acceleration(PGA)were observed,with the maxima reaching 145 cm/s and 2681 gal,respectively,and the intensity reached the highest level 7 on the Japanese(Japan Meteorological Agency,JMA)intensity standard,which is higher than level 10 of the United States Geological Survey(USGS)Modified Mercalli Intensity(MMI)standard.4)The observation of the very rare multiple strong pulse-like ground motion(PLGM)waveform poses a topic worthy of research in the field of earthquake engineering.5)As of January 7,the earthquake had left 128 deaths and 560 injuries in Ishikawa Prefecture,with 1305 buildings completely or partially destroyed,and had triggered a chain of disasters including tsunamis,fires,slope failures,and road ***,this paper summarizes the emergency rescue,information dissemination,and other disaster response and management measures taken in response to this *** work provides a reference case for carrying out effective responses,and offers lessons for handling similar events in the future.

关键词： Noto Peninsula Earthquake earthquake rupture mechanism earthquake disaster emergency response pulse-like ground motion

Structure regulating of metal clusters in carbonized metallic organic frameworks for high-efficient microwave absorption via tuning interaction strength between metals and ligands

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Nano Research 2024年第3期17卷 1699-1709页

作者： Chang Sun Kun-yan Zhao ming-Lu Huang cheng-Long Luo Xu-Dong chen ming Wang School of Chemistry and Chemical Engineering Chongqing Key Laboratory of Soft-Matter Material Chemistry and Function ManufacturingSouthwest UniversityChongqing 400715China Jieyang Branch of Chemistry and Chemical Engineering Guangdong Laboratory(Rongjiang Laboratory) Jieyang 515200China

Carbonized metallic organic frameworks(CMOF)have been attracting attention in microwave absorption(MA)research area because of their diverse structures,tunable compositions,and rich ***,structure regulation on metal clusters in CMOF is achieved by tuning the interaction strength between metals and ligands to enhance microwave absorption *** to relatively weak interaction among copper cations and ligands,copper nanoclusters(CuNC)can be uniformly formed and embedded within the cobalt/zinc(Co/Zn)***,copper cations are added to the Co/Zn bimetallic zeolitic imidazolate frameworks(ZIFs).Secondly,the CMOF composite particles with CuNCs(CuNCs/CoZn-CMOF)were developed by a pyrolysis *** CuNCs/CoZn-CMOF with an appropriate amount of CuNCs can harmonize both dielectric and magnetic *** a result,the minimum reflection loss(RLmin)reaches–45.1 dB at a matching thickness of 2.30 mm and the effective absorption bandwidth(EAB)is 8.80 GHz at a thickness of 3.10 *** broadband response to electromagnetic waves is attributed to interfacial polarization at CuNCs surface and heterogeneous interfaces,impedance matching and multiple scattering of electromagnetic *** study provides a feasible method to develop CMOF microwave absorption materials with high EAB values.

关键词： heterogeneous interface carbonized metallic organic frameworks microwave absorption interfacial polarization