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Electrochemical impedance analysis of nanoporous TiO_2 electrode at low bias potential

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Chinese Chemical Letters 2010年第8期21卷 959-962页

作者： Sheng Jun li Yuan lin zeng chen jing Bo Zhang Xiao wen Zhou College of Physics and Electrics He'nan University Kaifeng 475004 China Beijing National Laboratory for Molecular Sciences Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

TiO2 colloid was prepared by the sol-gel method and was bladed on transparent conduction glass to made nanoporous electrode. The impedance performance of TiO2 electrode was studied at various bias potential.A simplified equivalent circuit was proposed to investigate the charge transport impedance of TiO2 film and good fitting results were obtained.

关键词： Dye-sensitized solar cell Electrochemical impedance spectroscopy Equivalent circuit Charge transport impedance

Convenient folding-hot-pressing fabrication and enhanced piezoelectric properties of highβ-phasecontent poly(vinylidene fluoride)films

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Interdisciplinary Materials 2024年第5期3卷 715-725页

作者： Jie Shen Yicheng zeng Qiangzhi li jing Zhou wen chen State Key Laboratory of Advanced Technology for Materials Synthesis and Processing School of Materials Science and EngineeringWuhan University of TechnologyWuhanChina Sanya Science and Education Innovation Park Wuhan University of TechnologySanyaChina Hubei Longzhong Laboratory Wuhan University of Technology Xiangyang Demonstration ZoneXiangyangChina

Poly(vinylidene fluoride)(PVDF)is the most attractive piezoelectric polymer for application in flexible *** attain excellent piezoelectric properties,a substantial amount of spontaneous polarβ-phase content is highly ***,the current reported manufacturing methods to increaseβ-phase contents are inconvenient and complex,hindering progress in PVDF's *** work proposes a folding-hot-pressing method to fabricate highβ-phase-content PVDF *** characterization indicates that the films haveαandβphases and the folding-hot-pressing process transforms theαphase into theβ*** to the 97.5%β-phase content and aligned structure,a piezoelectric constant of 20 pC/N is achieved in the three-times folded ***,the process method enhances the tensile strength(126.2 MPa)of the films,with a low Young's modulus(0.87 GPa)remaining,making the films applicable for flexible piezoelectric ***,sensors based on the achieved films were assembled and applied for human physiological activity *** work offers a scalable new melt-processing strategy for developing high-performance PVDF-based piezo-electric composite films for wearable electronic devices.

关键词： flexible sensors highβ-phase content piezoelectric properties PVDF film

Preparation and performance of dye-sensitized solar cells based on ZnO-modified TiO_2 electrodes

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International Journal of Minerals,Metallurgy and Materials 2010年第1期17卷 92-97页

作者： Sheng-jun li Yuan lin Wei-wei Tan jing-bo Zhang Xiao-wen Zhou Jin-mao chen zeng chen College of Physics and Electrics He＇nan University Kaifeng 475004 China Beijing National Laboratory for Molecular Sciences Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

The ZnO-modified TiO2 electrode was prepared by adding Zn（CH3COO）2·2H2O to the TiO2 colloid during the sol-gel production process, and was used in dye-sensitized solar cells （DSCs）. The open circuit voltage （Voc） and fill factor （if） of the cells were improved sig- nificantly. The performances of the ZnO-modified TiO2 electrode such as dark current, transient photocurrent, impedance, absorption spectra, and fiat band potential （Vfb） were investigated. It is found that the interface charge recombination impedance increases and Vfb shifts about 200 mV toward the cathodic potential. The effect mechanism of ZnO modification on the performance of DSCs may be that ZnO occupies the surface states of the TiO2 film.

关键词： dye-sensitized solar cells TiO2 electrode modification photoelectrochemical properties

Myofiber development during embryonic to neonatal development in duck breeds differing in muscle growth rates

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Journal of Integrative Agriculture 2016年第2期15卷 403-413页

作者： li Hui-fang SHU jing-ting SHAN Yan-ju chen wen-feng SONG Chi XU wen-juan Key Laboratory for Poultry Genetics and Breeding of Jiangsu Province Institute of Poultry Science Chinese Academy of Agricultural Science Yangzhou 225125 P.R. China Jiangsu Tengdayuan Co. Ltd. Jiangyan 225538 P.R. China

little is known about the muscle developmental patterns during embryonic to neonatal development in *** investigated the developmental patterns in the lateral gastrocnemius muscles of Gaoyou and Jinding ducks differing in their muscle growth rates during the final stages of egg incubation and the first week after *** of the MyoD gene was quantified by quantitative real-time PCR（qRT-PCR）.The average cross-sectional area and diameter of the fibers increased from embryonic day 21（E21）,peaking at E27,and then declining slightly 7 d after *** density of the fibers decreased initially but increased after hatching in both breeds and *** within-breed variation in muscle fiber-type composition was greater than the average variation between the ***,the percentage of type Ⅰ fibers increased and that of type lib fibers decreased ***,the percentage of type lla fibers was almost constant as development proceeded in both duck *** profiles of MyoD mRNA expression were similar in both breeds,and a significantly positive relationship was observed between the expression of MyoD and the percentage of type lib *** study firstly revealed the characteristics of duck muscle development and differences between the two breeds differing in growth ***,type lib fibers might convert to type Ⅰ fibers in the lateral gastrocnemius,while MyoD may potentially function in controlling the muscle fiber phenotype during the secondary myogenesis of muscle development.

关键词： duck myofiber development MyoD gene gene expression

Geophysical characteristics of anthracites with various structures: a case study on the southern Qinshui Basin, north China

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Frontiers of Earth Science 2022年第3期16卷 696-710页

作者： juan TENG Zhigang wen chen li lingye MENG Hubei Key Laboratory of Petroleum Geochemistry and Environment Yangtze UniversityWuhan 430100China College of Resources and Environment Yangtze UniversityWuhan 430100China Research Institute Company limited CNOOCBeijing 100028China Institute of Petroleum Exploration and Development of PetroChina Tarim Oilfield Korla 841000China

Deformation of coals under tectonic movements could cause reduction of mechanical strength and enhancement of gas adsorption,which might result in coal and gas outburst,and cause safety and environmental *** this study,geophysical characteristics of coals with various structures were investigated with a special emphasis on characterization of pore size distribution,rock mechanical strength,acoustic emission,resistivity and acoustic velocity of anthracites with three types of structures in the Qinshui Basin,north *** studied No.3 coal seam developed three types of structures,namely undeformed coal,cataclastic coal,and granular *** observations under scanning electron microscope and pore size distribution using N2 and CO_(2) adsorption of anthracites of three types show that the undeformed coal consists of primary micropores,and cataclastic coal is mainly composed of mesopores and well-connected *** comparison,granular coal has the least *** mechanical strength,acoustic emission,resistivity and acoustic velocity of coals with three structure types were investigated under uniaxial and triaxial *** increasing degree of deformation of anthracites,compression strength,Young’s modulus,density,acoustic emission counting and acoustic velocity decreases,while resistivity *** suggest that the evolution of pore size distribution of anthracites with increasing degree of deformation contributed to variations of geophysical characteristics of coals with different structures to some extent.

关键词： geophysical characteristics coal structures pore size distribution acoustic emission electrical resistivity acoustic velocity

The occurrence order and cross-talk of different tRNA modifications

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Science China(life Sciences) 2021年第9期64卷 1423-1436页

作者： jing li wen-Yu Zhu wen-Qing Yang Cai-Tao li Ru-juan liu School of life Science and Technology ShanghaiTech UniversityShanghai 201210China

Chemical modifications expand the composition of RNA molecules from four standard nucleosides to over 160 modified nucleosides,which greatly increase the complexity and utility of *** RNAs(tRNAs)are the most heavily modified cellular RNA molecules and contain the largest variety of *** of tRNAs is pivotal for protein synthesis and also precisely regulates the noncanonical functions of *** in tRNA modifications lead to numerous human *** to now,more than 100 types of modifications have been found in ***,some modifications occur widely on all tRNAs,while others only occur on a subgroup of tRNAs or even only a specific *** modification frequency of each tRNA is approximately 7% to 25%,with 5-20 modification sites present on each *** occurrence and modulation of tRNA modifications are specifically noticeable as plenty of interplays among different sites and modifications have been *** particular,tRNA modifications are responsive to environmental changes,indicating their dynamic and highly organized *** this review,we summarized the known occurrence order,cross-talk,and cooperativity of tRNA modifications.

关键词： tRNA RNA modification RNA methylation occurrence order cross-talk

Interleukin-4 promotes microglial polarization toward a neuroprotective phenotype after retinal ischemia/reperfusion injury

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Neural Regeneration Research 2022年第12期17卷 2755-2760页

作者： Di chen cheng Peng Xu-Ming Ding Yue Wu Chang-juan zeng li Xu wen-Yi Guo Department of Ophthalmology Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghaiChina Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology ShanghaiChina

Glaucoma results from irreversible loss of retinal ganglion cells(RGCs)through an unclear *** polarization and neuroinflammation play an important role in retinal *** study aimed to explore the function of microglial polarization during glaucoma progression and identify a strategy to alleviate retinal *** ischemia/reperfusion injury was induced in C57BL/6 *** a separate cohort of animals,interleukin(IL)-4(50 ng/mL,2μL per injection)or vehicle was intravitreally injected after retinal ischemia/reperfusion *** loss was assessed by counting cells that were positive for the RGC marker RNA binding protein,mRNA processing factor in retinal flat *** expression of classically activated(M1)and alternatively activated(M2)microglial markers were assessed by quantitative reverse transcription-polymerase chain reaction,immunofluorescence,and western *** results showed that progressive RGC loss was accompanied by a continuous decrease in M2 microglia during the late phase of the 28-day period after retinal ischemia/reperfusion ***-4 was undetectable in the retina at all time points,and intravitreal IL-4 administration markedly improved M2 microglial marker expression and ameliorated RGC loss in the late phase post-retinal ischemia/reperfusion *** summary,we observed that IL-4 treatment maintained a high number of M2 microglia after RIR and promoted RGC survival.

关键词： glaucoma hyper-intraocular pressure in vivo interleukin-4 intravitreal injection M2 microglia neurodegeneration neuroprotective effect retinal ganglion cell retinal ischemia-reperfusion

Multi-scale morphology analysis of acoustic emission signal and quantitative diagnosis for bearing fault

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Acta Mechanica Sinica 2016年第2期32卷 265-272页

作者： wen-jing Wang ling-li Cui Dao-Yun chen School of Mechanical Electronic and Control EngineeringBeijing Jiaotong University College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology

Monitoring of potential bearing faults in operation is of critical importance to safe operation of high speed *** of the major challenges is how to differentiate relevant signals to operational conditions of bearings from noises emitted from the surrounding *** this work,we report a procedure for analyzing acoustic emission signals collected from rolling bearings for diagnosis of bearing health conditions by examining their morphological pattern spectrum（MPS） through a multi-scale morphology analysis *** results show that acoustic emission signals resulted from a given type of bearing faults share rather similar MPS *** examinations in terms of sample entropy and Lempel-Ziv complexity of MPS curves suggest that these two parameters can be utilized to determine damage modes.

关键词： Bearing fault Acoustic emission Morphological pattern spectrum(MPS) Sample entropy Lempel-Ziv complexity

How did high temperature extremes in southern Xinjiang,China induce the repaid rise in jujube futures prices in the summer of 2021?

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Advances in Climate Change Research 2023年第3期14卷 449-457页

作者： De-Qian li Shu-juan HU jing-jing ZHANG chen-Bin GAO Bing-Qian ZHOU wen-Xin ZHANG Key Laboratory for Semi-Arid Climate Change of the Ministry of Education College of Atmospheric SciencesLanzhou UniversityLanzhou 730000China

In the summer of 2021,southern Xinjiang,China,experienced a temporary period of high temperature *** of this weather event,jujube futures prices rose by more than 50%in a short *** clarify the influence mechanism of these two events,we investigated the current status of jujube farming and collected investors’online *** analysed these comments specifically using textual analysis tools,such as co-word *** showed that the concerns of investors about the reduction in jujube production triggered by high temperature extremes were the primary reason for the rapid rise in jujube futures *** in combination with the cultivation density of jujube and their adaptability to the growing environment,a new understanding can be *** is to say,when a crop is excessively densely cultivated in a region and is highly sensitive to a meteorological variable anomaly at a certain growth stage,a less destructive local extreme weather event could induce severe panic among investors regarding production reduction and thus influence the normal changes in futures *** response to the impact mechanisms revealed in this study,we proposed policy recommendations,such as strengthening the degree of crop damage disclosure and designing weather futures derivatives,to address similar situations in the *** study not only fills the gap in the research on the impact paths of high temperature extremes on jujube futures prices but also has a reference value for securing the stability of futures prices of related agricultural products in the future.

关键词： Jujube futures prices High temperature extremes Co-word networks Market hot topics Southern Xinjiang