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Acoustic radiation force on thin elastic shells in liquid

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Chinese Physics B 2020年第9期29卷 337-342页

作者： Run-Yang Mo Jing Hu Shi chen cheng-hui Wang Shaanxi Key Laboratory of Ultrasonics School of Physics and Information TechnologyShaanxi Normal UniversityXi'an 710119China

Based on the coupled acoustic scattering of two neighboring fluid-filled thin elastic shells suspending in an unbounded viscous liquid,an analytical method is developed to calculate the acoustic radiation force(ARF)of the *** physical effects are taken into account:elastic radiation scattering and the multiple interactions of *** results reveal that the magnitude of ARF can be enhanced by the sound radiation from the elastic shell undergoing forced vibrations and two resonant peaks can be observed on the ARF function *** feature of the lower peak is determined by the interactions and acoustic response of the back *** attractive forces can be obtained in the low kR1 band for the case of radius ratio R2/R1>1,while the magnitude of ARF at the lower peak may be influenced to some extent by acoustic shielding phenomenon for the case of radius ratio R2/R1<***,the interactions of particles cannot be *** results may provide a theoretical basis for precisive manipulation of multiple particle systems.

关键词： thin elastic shell radiation force elastic radiation scattering mutual interactions

One-Pot Synthesis of 4-Aryl-NH-1,2,3-Triazoles through Three- Component Reaction of Aldehydes, Nitroalkanes and NaN3

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Chinese Journal of Chemistry 2017年第12期35卷 1808-1812页

作者： Rongrong hui Mina Zhao Ming chen Zhihui Ren Zhenghui Guan Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education Department of Chemistry & Materials Science Northwest University Xi'an Shaanxi 710127 China Shaanxi Key Laboratory of Phytochemistry College of Chemistry and Chemical Engineering Baoji University of Arts and Sciences Baoji Shaanxi 721013 China

A one-pot three-component reaction of aldehydes, nitroalkanes and NaN3 for the synthesis ofNH-1,2,3-triazoles has been developed. The reaction provides a safe, efficient and step-economic approach for the synthesis of... 详细信息

关键词： aldehydes sodium azide one-pot three-component reaction NH-1,2,3-triazoles

Reprocessible Epoxy Networks with Tunable Physical Properties:Synthesis,Stress Relaxation and Recyclability

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Chinese Journal of Polymer Science 2018年第5期36卷 641-648页

作者： Jia-hui chen Xu-Pei An Yi-Dong Li Ming Wang Jian-Bing Zeng School of Chemistry and Chemical Engineering Southwest University

In order to extend the application of epoxy vitrimer, 1,4-cyclohexanedicarboxylic acid（CHDA） was used as a co-curing agent and structure modifier for sebacic acid（SA） cured diglycidyl ether of bisphenol A（DGEBA） epoxy vitrimer to tailor the mechanical properties of epoxy vitrimers with 1,5,7-triazabicylo[4.4.0]dec-5-ene（TBD） as a transesterification catalyst. The glass transition temperature（Tg） of vitrimer increased gradually with the increase in CHDA content. Vitrimers behaved from elastomer to tough and hard plastics were successfully achieved by varying the feed ratio of CHDA to SA. Both the Young＇s modulus and storage modulus increased apparently with the increase in CHDA content. Stress relaxation measurement indicated that more prominent stress relaxation occurred at elevated temperatures and the stress relaxation decreased with the increase of CHDA content due to the reduced mobility of the vitrimer backbone. The vitrimers showed excellent recyclability as evidenced by the unchanged gel fraction and mechanical properties after compression molded for several times. With tunable mechanical properties, the epoxy vitrimers may find extensive potential applications.

关键词： Epoxy vitrimer Mechanical properties Stress-relaxation Recyclability

Structural modification of BODIPY: Improve its applicability

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Chinese Chemical Letters 2019年第10期30卷 1815-1824页

作者： Mengdi Liu Siyue Ma Mengyao She jiao chen Zhaohui Wang Ping Liu Shengyong Zhang Jianli Li Ministry of Education Key Laboratory of Synthetic and Natural Functional Molecule Chemistry College of Chemistry & Materials Science Northwest University

BODIPY has been considered a potential scaffold because of their neutral total charge, sharp absorption,and emission with high fluorescence quantum yield. However, the drawback of emission wavelength at less than 600 nm and hydrophobicity limit its application. One of the extremely interesting properties of BODIPY is that small modifications to their structures could be able to tune their properties, mainly including the absorption/emission wavelength and the hydrophilicity. This review focuses on the modification at different positions of BODIPY to improve the water-solubility and emission wavelength that describe their spectral, photophysical properties and applicability, which is helpful for the researchers to rationally design BODIPY dyes to adapt a wide range of applications.

关键词： BODIPY Near-infrared Water solubility Modification Application

Electrocatalytic activity of non-precious metal catalyst Co-N/C toward oxygen reduction reaction

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Chinese Chemical Letters 2010年第8期21卷 983-986页

作者： Yu Jun Si Chang Guo chen Wei Yin hui Cai College of Chemistry and Chemical Engineering Chongqing University Chongqing 400044 China College of Chemistry and Pharmaceutical Engineering Sichuan University of Science and Engineering Zigong 643000 China The Key Laboratory for the Exploitation of Southwest Resources and Environmental Disaster Control Engineering under Ministry of Education Chongqing University Chongqing 400044 China

Metallic cobalt was deposited on acetylene black to synthesize a composite Co/C by chemical reduction method.A platinumfree electrocatalyst Co-N/C（800） for oxygen reduction reaction（ORR） was synthesized by mixing the composite Co/C with urea and heat-treating at 800℃.The results from linear sweep voltammograms indicated that the Co-N/C（800） is active to ***β-Co and cobalt oxides are not the active site of the catalyst Co-N/***,the existence of cobalt facilitated the modification of nitrogen to carbon black and led to the formation of active site of catalyst Co-N/C（800）.

关键词： Oxygen reduction reaction Electrocatalyst Non-precious metal Active site

Mechanical and thermal properties of sodium silicate treated moso bamboo particles reinforced PVC composites

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Science China(Technological Sciences) 2010年第11期53卷 2932-2935页

作者： WANG hui SHENG KuiChuan chen Jie MAO HaiLiang QIAN XiangQun School of Biosystems Engineering and Food Science Zhejiang UniversityHangzhou 310029China

The main objective of this research was to study the potential of sodium silicate modification on moso bamboo particles as reinforcements for thermoplastic. Moso bamboo particles were modified with sodium silicate aqueous solutions (of 0.5%, 1%, 2%, 5% and 10% concentrations). The mechanical properties of sodium silicate treated moso bamboo particles reinforced PVC composites (BPPC) were calculated and compared with raw bamboo particles filled samples. The thermal characteristics of the BPPC were studied to investigate the feasibility of sodium silicate treatment on moso bamboo particles. The particle morphology and BPPC microstructure were investigated by scanning electron microscopy. Results showed that the tensile strength and modulus of elasticity of the BPPC increased before the concentration of sodium silicate solution reached 5% and got their maximum values of 15.72 MPa and 2956.80 MPa, respectively at 5% concentration. The modulus of rupture obtained the maximum value of 27.73 MPa at 2% concentration. The mechanical curve decreased as the concentration of solution went higher. Differential scanning calorimetric analysis illustrated that the sodium silicate solution treated BPPC possesses a better compatibility. More uniform dispersion of moso bamboo particles in PVC matrix was obtained after the sodium silicate treatment. Hence, the sodium silicate was a feasible and competitive agent of creating moso bamboo particles reinforced PVC composites.

关键词： composites moso bamboo particles polyvinylchloride mechanical properties thermal property

Measurement on soil deformation caused by expanded-base pile in transparent soil using particle image velocimetry (PIV)

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Journal of Mountain Science 2017年第8期14卷 1655-1665页

作者： QI Chang-guang ZHENG Jin-hui ZUO Dian-jun chen Geng Faculty of Architectural Civil Engineering and EnvironmentNingbo University Tianjin Research Institute for Water Transport Engineering M.O.T. Geotechnical Research Institute Hohai University

A new small-scale geotechnical physical model in 1-g and unconfined condition, combining the transparent soil, close-range photogrammetry and particle image velocimetry(PIV), was employed, which provides a non-intrusively internal deformation measurement approach to monitor the internal deformation of soil caused by expanded-base pile jacking with casing. The transparent soil was made of fused quartz and its refractive index matched blended oil, adding reflective particles(glass beads). Closerange photogrammetry was employed to record the images of the process of casing jacking and extraction in transparent soil, allowing the use of Matlab-based Geo-PIV to figure out the displacement field converted from image space to object space. Analysis of test results indicates that the maximum displacement caused by casing jacking for expandedconical-base pile is decreased by 29% compared with that for expanded-flat-base pile. The main movement happens at the early stage of casing extraction. The maximum displacement caused by casing extraction for the conical base is about 43% of that for the flatbase, while the affected zone caused by casing extraction for the conical base accounts for about 1/3 of that for the flat base. The contraction for horizontal displacements tends to decrease with the depth increasing. By contrast, the contraction under pile base decreases with the increasing of displacement. The displacements generated by jacking a conventional pile having a diameter equal to the casing diameter of the expanded-base pile were comparable to the net displacement taking place due to expanded-base pile installation for the conical base pile.

关键词： Geotechnical physical model Expanded-base pile Transparent soil Particle image velocimetry(PIV) Close-range photogrammetry

Using nutritional assessment to predict gender-specific risks of sarcopenia among the elderly receiving health check-up in Taipei

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Journal of Geriatric Cardiology 2016年第3期13卷 261-266页

作者： Ya-hui HUANG Yi-Fen LIN Mei-Ju chen Food and Nutrition Department Heping Fuyou Branch of Taipei City Hospital Taiwan China Department of Family Medicine Heping Fuyou Branch of Taipei City Hospital Taiwan China College of Healthcare Administration and Management National Taipei University of Nursing and Health Science Taiwan China

Quality of life for the elderly in an ageing society is receiving more attention than ever. After age 40, muscle mass loses at the rate of 3% to 8% every 10 years. More- over, the decline intensifies after 60 years old. Although many people do not experience changes in total body weight, their muscle mass is slowly replaced by body fat. Decreased muscle mass means lower muscle strength, which affects physical functioning. As a result, daily activities become con- strained, risks of fall and bone fracture elevated,

关键词： Gender Mini-nutritional assessment Sarcopenia

Comparison of pseudophakic retinal straylight in spherical/aspherical and hydrophobic/hydrophilic intraocular lens

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International Journal of Ophthalmology(English edition) 2015年第6期8卷 1146-1150页

作者： Yong Tang hui Song Jing chen Xin Tang Cataract Center Tianjin Eye Hospital

AIM: To study the potential reasons of increased straylight in pseudophakic eyes. METHODS: Cross -sectional study. Seventy patients diagnosed as bilateral age-related cataract and implanted with Tecnis ZA9003, Sensar AR40e, SA6OAT, XLSTABI ZO or Akeros AO intraocular lens (IOL) were enrolled in this research. Straylight was measured by a C -Quant straylight meter three to four weeks postoperatively. Five different modalities of IOL, including spherical/aspherical optics and hydrophobic/hydrophilic material were tested in this study. Normal as well as dilated pupils were used. The main outcome variable for straylight measurement was the logarithmic straylight parameter, log(s). RESULTS: The straylight parameter increased significantly after pupil dilation (P<0.05). Straylight of aspherical IOL was significantly higher after pupil dilation (P<0.06) compared to spherical IOL. In normal pupil, straylight of hydrophobic IOL was significant higher when compared with hydrophilic IOL (P<0.05). CONCLUSION: Straylight and visual acuity stand for the different aspects of visual function. Several factors including pupil diameter, optic material, aspherical design of IOL influence intraocular light scattering in pseudophakic eyes. Further investigation was needed to study the impact of optic material and optic surface design on pseudophakic straylight.

关键词： light scattering retinal straylight pseudophakia