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Structural Characterization and Luminescence Properties of Two 4d-4fLn-Ag Coordination Compounds Based on Dinuclear Lanthanide Clusters

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Chemical Research in Chinese Universities 2014年第2期30卷 194-199页

作者： ZHANG Yu CHEN Lei JU weiwei XU yan State Key Laboratory of Materials-oriented Chemical Engineering College of Chemistry and Chemical EngineeringNanjing Tech University Nanjing 210009 P.R.China

Two new compounds,[ErAg（INA）2（C2O4）]·2H2O（1）（HINA=nicotinic acid） and [Tb0.8Y0.2Ag2（IN）4·（H2O）5]·NO3·2H2O（2）（HIN=isonicotinic acid）,based on the {Ln2} building units,have been hydrothermally synthesized and characterized by single-crystal X-ray diffraction,infrared spectroscopy,thermal analysis and powder X-ray diffraction（PXRD）.Single-crystal X-ray diffraction data reveal that both compounds crystallized in the low-symmetry triclinic space group P1-.Compound 1 is a 3D heterometallic coordination framework based on {Er2}clusters,oxalate ligands and bridging [Ag（INA）] linkers,while compound 2 consists of 0D [Tb0.8·Y0.2Ag2（IN）4（H2O）5]2 subunits that give a 3D supramolecular structure through hydrogen bond *** photoluminescent properties of both compounds（1 and 2） were studied.

关键词： 4d-4fLn-Ag coordination compound Doping Hydrothermal synthesis Crystal structure

Photocatalytic degradation of carbofuran in TiO_2 aqueous solution: Kinetics using design of experiments and mechanism by HPLC/MS/MS

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Journal of Environmental Sciences 2013年第8期25卷 1680-1686页

作者： Hai yang Shuolin Zhou Huajie Liu weiwei yan Liping yang Bing Yi College of Chemistry and Chemical Engineering Hunan Institute of Engineering College of Chemistry and Chemical Engineering Hunan Normal University South China Institute of Environmental Sciences Ministry of Environmental Protection

The photocatalytic degradation kinetics of carbofuran was optimized by central composite design based on response surface methodology for the first time. Three variables, TiO2 concentration, initial pH value and the concentration of carbofuran, were selected to determine the dependence of degradation efficiencies on independent variables. Response surface methodology modeling results indicated that the degradation efficiency of carbofuran was highly affected by the initial pH value and the concentration of carbofuran. Then nine degradation intermediates were detected by HPLC/MS/MS. The Frontier Electron Densities of carbofuran were calculated to predict the active sites on carbofuran attacked by hydroxyl radicals and photoholes. Point charges were used to elucidate the chemisorption pattern on TiO2 catalysts during the photocatalytic process. By combining the experimental results and calculation data, the photocatalytic degradation pathways of carbofuran were proposed, including the addition of hydroxyl radicals and the cleavage of the carbamate side chain.

关键词： carbofuran photocatalytic degradation central composite design kinetics mechanism

Effects of 1-methylcyclopropene on skin greasiness and quality of'Yuluxiang'pear during storage at 20℃

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Journal of Integrative Agriculture 2024年第7期23卷 2476-2490页

作者： Wanting Yu Xinnan Zhang weiwei yan Xiaonan Sun yang Wang Xiaohui Jia Research Institute of Pomology Chinese Academy of Agricultural SciencesXingcheng 125100China

During storage at 20℃,specific pear cultivars may exhibit a greasy texture and decline in quality due to fruit *** these varieties,‘Yuluxiang’is particularly susceptible to peel greasiness,resulting in significant economic ***,there is an urgent need for a preservative that can effectively inhibit the development of *** studies have demonstrated the efficacy of 1-methylcyclopropene(1-MCP)in extending the storage period of *** hypothesize that it may also influence the occurrence of postharvest peel greasiness in the‘Yuluxiang’*** this study,we treated‘Yuluxiang’pears with *** stored them at 20℃while analyzing the composition and morphology of the surface waxes,recording enzyme activities related to wax synthesis,and measuring indicators associated with fruit storage quality and physiological *** results demonstrate that prolonged storage at 20℃leads to a rapid increase in skin greasiness,consistent with the observed elevations in L^(*),greasiness score,and the content of total wax and greasy wax ***,there were indications that cuticular waxes underwent melting,resulting in the formation of an amorphous *** comparison to controls,the application of 1-MCP significantly inhibited increments in L^(*) values as well as grease scores while also reducing accumulation rates for oily waxes throughout most stages over its shelf period,additionally delaying transitions from flaky-wax structures towards their amorphous *** the initial 7 d of storage,several enzymes involved in the biosynthesis and metabolism of greasy wax components,including lipoxygenase(LOX),phospholipase D(PLD),andβ-ketoacyl-CoA synthase(KCS),exhibited an increase followed by a subsequent *** activity of LOX during early shelf life(0–7 d)and the KCS activity during middle to late shelf life(14–21 d)were significantly suppressed by ***,1-MCP effectively maintained firmness,

关键词： ‘Yuluxiang’pear skin greasiness 1-methylcyclopropene storage quality

Preparation and properties of CdS/Au composite nanorods and hollow Au tubes

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Chinese Science Bulletin 2010年第10期55卷 921-926页

作者： yanG ZhaoHui CHU HaiBin JIN Zhong ZHOU weiwei LI yan Beijing National Laboratory for Molecular Sciences Key Laboratory for the Physics and Chemistry of Nanodevices College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

1-dimensional (1D) metal-semiconductor nano-scale composite superstructures based on Au nanoparticles and CdS nanorods were *** outer surface of CdS nanorods was modified with mercapto-ethylamine (MEA) in *** the aid of MEA,dense and uniform Au nanoparticles were deposited onto the external wall of CdS nanorods through in situ chemical reduction of *** Au nanoparticles induced further electroless deposition and a continuous layer of Au was formed on CdS *** hollow Au tubes were obtained after the inner CdS cores were etched by ***-Vis,FL,XPS,EDX,TEM and SEM measurements were carried out to characterize the produced *** quenching of the defect emission of CdS in CdS-nanorod/Au-nanoparticle hybrid superstructures was detected,which was ascribed to the energy transfer from the exciton of CdS to surface plasma resonance level of Au.

关键词： CdS纳米棒金纳米粒子纳米复合材料硫化镉空心表面等离子体共振光电子能谱性能

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少数族群文学研究:观念与方法的反思

文艺理论研究 2015年第5期35卷 60-66,176页

作者：闫炜炜华东师范大学人文学院新疆维吾尔自治区党校文化学教研部

少数族群文学作为中国文学的一部分,近几十年来备受瞩目。鉴于当下对于少数族群文学的不同切入点的研究,进行思想观念和理论方法的反思,使成果得以突出,使偏颇得以显明并矫正,其目的不仅在于为少数族群文学研究开辟新的研究空间和注入... 详细信息

少数族群文学作为中国文学的一部分,近几十年来备受瞩目。鉴于当下对于少数族群文学的不同切入点的研究,进行思想观念和理论方法的反思,使成果得以突出,使偏颇得以显明并矫正,其目的不仅在于为少数族群文学研究开辟新的研究空间和注入新的活力,而且有助于各族群文学发展的和谐化及互补互查互助。并由此引发出少数族群文学发展及研究的未来走向和价值重建的思考。

关键词：少数族群文学观念方法反思

A study on service quality evaluation of digital libraries in China based on tetra-class model

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Chinese Journal of Library and Information Science 2013年第2期6卷 14-32页

作者： Changping HU weiwei yan Yuan HU Center for Studies of Information Resources Wuhan University

Purpose: This study intends to evaluate the service quality of academic digital libraries(DLs)in China. By utilizing tetra-class model which concentrates on categorizing services according to their contributions to user satisfaction, this paper attempts to visually categorize the specific DL service elements to reveal their present performances, and then further explain the categorizing variations among different groups of users to discover the user ***/methodology/approach: This paper carries out a survey to evaluate user experience on 27 typical DL services summarized from our investigations of representative Chinese university DLs. Based on the five-point Likert-type scale evaluation, the users’ attitudes toward specific service element are divided into negative and positive dimensions. Afterwards,a correspondence analysis is applied to calculate the contributions to satisfaction and dissatisfaction of each service element based on tetra-class model. As a result, the DL service elements of Chinese academic libraries are classified into four categories(i.e. Basic, Secondary,Plus, and Key). Finally, we compared the categorizing ***: The results show that the DL service elements of Chinese academic libraries are all distributed in Basic and Key services regarding information retrieval and informationorganizing; 80% of the interaction services elements are Plus services, while 50% of the Secondary services are information-providing services. The results also reveal that service categorization is obviously influenced by the users’ education background, especially their disciplines. Furthermore, the users who are older, more highly-educated, or studying in higher reputation universities are more likely to evaluate DL services as either critical or *** limitations: Tetra-class model cannot reveal the interplay among the DL service elements. In addition, the user segmentation in our studies is limited to the sample ***

关键词： Digital library(DL) Tetra-class model User satisfaction User preference User characteristic Service categorization

Simulation of flow through porous anode in MFC at higher power density

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Theoretical & Applied Mechanics Letters 2012年第2期2卷 49-53页

作者： weiwei Su weiwei yan Zhongdi Su yang Liu Yousheng Xu Department of Physics Zhejiang Normal UniversityJinhua 321003China College of Metrology&Measurement Engineering China Jiliang UniversityHangzhou 310018China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina

Microbial fuel cell （MFC） is a novel environmental friendly energy device which has received great attention due to its technology for producing electricity directly fi-om organic or inorganic matter by using bacteria as catalyst. To date, many experiments have been carried out to achieve the maximum power output with advective flow through porous anode to the cathode in the MFC. However, the precise mechanical mechanism of flow through anode and the quantified relationship between electrode spacing and MFC performance are not yet clearly understood. It hasbeen found experimentally that the power output can be increased apparently at certain electrode spacing configuration. Based on these available experimental data, this paper investigates the effect of spacing between electrodes, the Darcy number of porous anode and the Reynolds number on the power production performance of MFC by using lattice Boltzmann method. The numerical simulation results present that the distance between electrodes significantly influences the flow velocity and residence time of the organic matter attached to the anode in the MFC. Moreover, it is found that the Darey number of porous anode and the Reynolds number can regulate the output efficiency of MFC. These results perform better understanding of the complex phenomena of MFC and will be helpful to optimize MFC design.

关键词： microbial fuel cell lattice Boltzmann method flow in porous media

Numerical Investigation of Flow Characteristics in the Obstructed Realistic Human Upper Airway

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Numerical Investigation of Flow Characteristics in the Obstr...

“自我惩罚”与“疾病书写”——田纳西·威廉斯悲剧创作评析

第九届全国流体力学学术会议

作者： Xingli Liu weiwei yan College of Metrology and Measurement Engineering China Jiliang University

In this study,the flow characteristics in the realistic human upper airway(HUA) with obstruction that resulted from pharyngeal collapse were numerically *** 3-D anatomically accurate HUA model was reconstructed from CT-scan images of a Chinese male patient(38 years,BMI 25.7).The computational fluid dynamics(CFD) with the large eddy simulation(LES) method was applied to simulate the inspiratory and expiratory airflows dynamics in the HUA ***,the laser Doppler anemometry(LDA) technique was simultaneously adopted to measure the airflow fields in the HUA model for the purpose of testifying the reliability of LES *** the simulations,the representative respiration intensities of 16.8 L/min(slight breathing),30 L/min(moderate breathing),and 60 L/min(severe breathing) were conducted under continuous inspiration and expiration *** airflow velocity field and static pressure field were obtained and discussed in *** results indicated the air in the HUA model experiences unsteady transitional/turbulent flow under low Reynolds *** airflow fields occurs forceful injection phenomenon due to the narrowing of pharynx caused by the respiratory illness during both inspiration and expiration *** also exists strong flow separation and back flow inside obstructed HUA owing to the vigorous jet flow effect in the *** present results would provide theoretical guidance for the treatment of obstructive respiratory disease.

关键词： upper airway flow characteristics circular breathing obstructive sleep apnea large eddy simulation

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戏剧艺术 2021年第2期 125-135页

作者：晏微微黄冈师范学院外国语学院

田纳西·威廉斯将性作为自由和生命力的隐喻,以"自我惩罚"的机制来强化欲望书写,提升遵循"情欲法则"的牺牲者悲剧的崇高感,坚持"把疾病作为认识手段"来揭露事物的真相。在威廉斯看来,性欲受到压抑往往使人陷入精神错乱或精神崩溃,清醒... 详细信息

田纳西·威廉斯将性作为自由和生命力的隐喻,以"自我惩罚"的机制来强化欲望书写,提升遵循"情欲法则"的牺牲者悲剧的崇高感,坚持"把疾病作为认识手段"来揭露事物的真相。在威廉斯看来,性欲受到压抑往往使人陷入精神错乱或精神崩溃,清醒认识到自身的本能欲望者为了从精神困境中解脱而采取极端手段,却未必会酿成真正意义上的悲剧。威廉斯戏剧探索人类摆脱悲剧宿命的可能性,其创作拓展了悲剧诗学的空间,在西方现代悲剧史上具有重要的启示意义。

关键词：田纳西·威廉斯悲剧诗学疾病弗洛伊德学说