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Floral traits and pollination system of Zygophyllum xanthoxylum in the managed and wild populations in an arid region of Northwest China

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Journal of Arid Land 2015年第4期7卷 488-500页

作者： CHEN Min ZHAO Xueyong zuo xiao'an LIAN Jie ZHU Yangchun Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences University of Chinese Academy of Sciences

Zygophyllum xanthoxylum, which belongs to Sarcozygium of Zygophyllaceae, is one of the ecologically important species in Northwest China. In order to understand the pollination system of Z. xanthoxylum, we investigated the following characteristics of this species in the Urat Desert-grassland Research Station in western Inner Mongolia of China： flowering dynamics, pollen viability, pollen limitation, floral visitors and breeding system. The results showed that the flowering period and flowering peak were different between the wild and managed popula- tions, being longer in the managed population. Z. xanthoxylum was pollen-limited, and pollen limitation was more intense in the wild population than in the managed population. Chalicodoma deserticola （Hymenoptera） was found to be the most frequent pollinator in the wild population, while Anthophora fulvitarsis （Hymenoptera） was the most frequent and effective visitor in the managed population. Out-crossing was dominant in the breeding system and self-pollination just played an assistant role to assure the reproduction of Z. xanthoxylum.

关键词： Zygophyllum xanthoxylum pollination pollen limitation floral visitor fruit set seed set breeding system

D-A Copolymers Based on a Pentacyclic Acceptor Unit and a 3,3′-Difluoro-2,2′-bithiophene for Solar Cells

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Chinese Journal of Polymer Science 2017年第12期35卷 1457-1462页

作者： Jia-min Cao Liu Qian Dan He zuo xiao 丁黎明 Center for Excellence in Nanoscience (Chinese Academy of Sciences) Key Laboratory of Nanosystem and Hierarchical Fabrication (Chinese Academy of Sciences) National Center for Nanoscience and Technology

A D-A copolymer, P2FBTTPTI, was developed by copolymerizing a pentacyclic acceptor unit, thieno[2′,3′：5,6]pyrido[3,4-g]thieno[3,2-c]isoquinoline-5,11（4 H,10 H）-dione（TPTI）, with 3,3′-difluoro-2,2′-bithiophene（2 FBT）. P2 FBTTPTI possessed a low highest occupied molecular orbital（HOMO） energy level（-5.50 e V） and a good hole mobility（4.14 × 10^-4 cm^2·V^-1·s^-1）. P2FBTTPTI：PC_（71）BM solar cells gave a decent power conversion efficiency（PCE） of 7.64% and a high open-circuit voltage（Voc） of 0.95 V.

关键词： D-A copolymers Fluorination Open-circuit voltage Polymer solar cells

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“双碳”背景下《高分子化学实验》教学初探

广州化工 2024年第8期52卷 190-193页

作者：左晓玲焦慧彬高华向力贵州民族大学材料科学与工程学院贵州贵阳550025

将绿色低碳理念融入《高分子化学实验》课程建设,有助于培养综合能力优异的“双碳”人才。本文分析了课程现状,引入学生零距离接触科学研究的教学新模式,基于环保高效的可见光固化技术,将纳米级乳液的绿色合成及多重刺激响应特性研究纳... 详细信息

将绿色低碳理念融入《高分子化学实验》课程建设,有助于培养综合能力优异的“双碳”人才。本文分析了课程现状,引入学生零距离接触科学研究的教学新模式,基于环保高效的可见光固化技术,将纳米级乳液的绿色合成及多重刺激响应特性研究纳入教学体系,在文献调研、方案设计、实验操作、分析总结中贯彻“双碳”理念,以科学研究促进本科教学改革,旨在激发学生的科研兴趣和创新意识,为实现“双碳”人才培养目标提供可持续的支撑和保障。

关键词： “双碳” 教学改革可见光固化乳液多重刺激响应性

Singlet fission and its application in organic solar cells

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Journal of Semiconductors 2022年第8期43卷 1-6页

作者： Yamin Zhang zuo xiao Liming Ding Hao-Li Zhang State Key Laboratory of Applied Organic Chemistry Key Laboratory of Special Function Materials and Structure Design(MoE)College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China Tianjin Key Laboratory of Molecular Optoelectronic Sciences Collaborative Innovation Center of Chemical Science and EngineeringTianjin UniversityTianjin 300072China Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190China

Enhancing the power conversion efficiency(PCE)is the major task in the development of solar cells[1−5].In 1961,William Shockley and Hans *** pointed out that the highest PCE for a single-junction solar cell is limited to 31%due to the thermalization and transmission losses[6].Singlet fission(SF)is an appealing carrier-multiplication approach to break the Shockley-Queisser limit,since it converts one high-energy singlet exciton into two low-energy triplet ***,one absorbed photon generates two electron-hole pairs.

关键词： limit convert singlet

国际商务硕士CDIO人才培养模式探索——以华南师范大学为例

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广东水利电力职业技术学院学报 2024年第2期22卷 59-62,70页

作者：左小明韦梦梦马弘泷华南师范大学广州510630

培养具有国际视野、拥有创新能力的复合型人才,是全球化背景下高校创新人才培养的重要导向。对此,在“双一流”视域下,以华南师范大学国际商务硕士培养为例,引入构思(C)、设计(D)、实施(I)、运行(O)的CDIO理念,重点从课程体系、师资结... 详细信息

培养具有国际视野、拥有创新能力的复合型人才,是全球化背景下高校创新人才培养的重要导向。对此,在“双一流”视域下,以华南师范大学国际商务硕士培养为例,引入构思(C)、设计(D)、实施(I)、运行(O)的CDIO理念,重点从课程体系、师资结构、教学模式、评价体系四方面构建创新人才培养模式框架并提出优化建议,以期为创新人才培养提供参考和借鉴。

关键词：国际商务硕士 CDIO模型创新人才培养模式

The estimation method of GPS instrumental biases

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Chinese Science Bulletin 2001年第3期46卷 204-207页

作者： CHANG Qing ZHANG Donghe xiao zuo ZHANG Qishan Department of Geophysics Peking UniversityBeijing 100071China Department of Electronic Engineering Beijing University of Aeronautics and AstronauticsBeijing 100083China

A model of estimating the global positioning system (GPS) instrumental biases and the methods to calculate the relative instrumental biases of satellite and receiver are presented. The calculated results of GPS instrumental biases, the relative instrumental biases of satellite and receiver, and total electron content (TEC) are also shown. Finally, the stability of GPS instrumental biases as well as that of satellite and receiver instrumental biases are evaluated, indicating that they are very stable during a period of two months and a half.

关键词： GPS instrumental biases TEC ionosphere.

Induced J-aggregation in acceptor alloy enhances photocurrent

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Science Bulletin 2019年第15期64卷 1083-1086页

作者： Ling Liu Qishi Liu zuo xiao Shangfeng Yang Yongbo Yuan Liming Ding Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Department of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China School of Physics&Electronics Central South UniversityChangsha 410083China

Carbon-oxygen-bridged (CO-bridged) ladder-type units already proved to be promising electron-donating building blocks for making acceptor-donor-acceptor (A-D-A) nonfullerene acceptors [1].Compared with traditional carbon-bridged (C-bridged) units, CObridged units present stronger electron-donating capability due to electron-rich oxygen atoms.

关键词： PTB PCE J-aggregation

Microstructural Evolution and Performance of In-situ Ag-Ni Composite after Solidification under Electromagnetic Stirring and Deformation

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Journal of Iron and Steel Research International 2016年第7期23卷 638-646页

作者： Lin ZHANG Ke HAN Tian-nan MAN En-gang WANG xiao-wei zuo Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern University National High Magnetic Field Laboratory Florida State University

The effect of electromagnetic stirring（EMS）on microstructure and performance of Ag-8 mass%Ni composite was investigated under both solidified and deformed *** EMS,the Ag matrix formed short,thick dendrites in the ingot;whereas with EMS,dendrites were long and *** phase mainly formed particles or ribbons,distributed along boundaries between dendrite *** drawing of the solidified Ag-Ni ingots,both with and without EMS,produced high strength in-situ metal-matrix composite（MMC）consisting of Ag matrix reinforced by Ni *** improved the ductility of the composite,consequently enhancing its drawability and *** also increased the electrical conductivity in both solidified ingots and deformed in-situ composite *** both cases,hardness and tensile strength remained high.A model based on a combination of the modified linear rule of mixtures and the Hall-Petch relationship was used to rationalize the tensile strength and hardness with respect to its fabrication parameters and the microstructure of Ag-Ni in-situ composite.

关键词： Ag-Ni electromagnetic stirring solidification in-situ metal matrix composite

High-temperature oxidation behavior of a cast Ti-47.5Al-2.5V-1.0Cr-0.2Zr alloy

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China Foundry 2022年第5期19卷 443-454页

作者： Xue-jian Lin Hong-jun Huang xiao-guang Yuan Yin-xiao Wang Bo-wen Zheng xiao-jiao zuo Ge Zhou School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

The oxidation behavior of the Ti-47.5Al-2.5V-1.0Cr-0.2Zr alloy at 900℃ was investigated at different oxidation times(5,20,60 and 100 h).The results show that the total weight gain of the alloy after 100 h at 900℃ oxidation is 9.1 g·m^(-2),and the oxidation rate decreases with oxidation *** oxides on the alloy surface are mainly TiO_(2) and Al_(2)O_(3).At the beginning of oxidation(5 h),the oxide film is relatively complete,thin,and the interface between the oxide layer and the matrix is virtually *** the end of oxidation(100 h),the thickness of the oxide film is expanded,cracking and spalling occur,and the spalling form is intra-film *** the same time,oxygen is mainly distributed in the oxide film and the oxygen content in the alloy substrate is reduced,confirming that the TiAl alloy has a certain oxidation stability at 900℃.From the outer surface of the oxide layer to the matrix,the TiO_(2) content increases and the Al_(2)O_(3) content *** proceeds to completion in this system via the dissolution and diffusion of O atom.

关键词： cast TiAl alloy high temperature oxidation oxidation film oxidation behavior