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Tetraphenylethene-based hole transporting material for highly efficient and stable perovskite solar cells

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Science China Chemistry 2024年第6期67卷 2009-2015页

作者： Peng Wang Pei Yuan Chenghao Ge Rongjun Zhao Lin xie Yong Hua School of Materials and Energy Yunnan UniversityKunming650091China

2,2,7,7-Tetrakis-(N,N-di-p-methoxyphenylamine)-9,9-spirobifluorene(Spiro-OMeTAD)has been identified as the most widely used and effective hole transporting material(HTM)in perovskite solar cells(PSCs).However,the complicated multistep synthesis and low intrinsic hole mobility of Spiro-OMe TAD limit its commercialized ***,developing highly efficient HTMs with less synthetic steps becomes increasingly ***,understanding hot carriers transfer dynamics at the interface of perovskite layer and hole transport layer is crucial for further enhancing PSCs performance towards Shockley-Queisser limit,which still lacks full investigation to ***,a new HTM based on tetraphenylethene(WP1)was successfully synthesized by a simple one-step reaction *** was found that WP1-based HTM exhibits more matched energy level,higher hole mobility and conductivity than those of the control Spiro-OMe *** femtosecond transient absorption results reveal that the transfer rate of hot holes in perovskite/WP1 sample is four times higher than that of perovskite/Spiro-OMeTAD,thereby helping enhance the device ***,the efficiency of PSCs is enhanced to 24.04%(WP1)from 22.85%(Spiro-OMeTAD).Moreover,the un-encapsulated device prepared with WP1 exhibits better long-term stability,retaining 87%of its initial PCE value after storing for 72 days under air environment,while the reference device shows76%of its initial *** work indicates that simple tetraphenylethene-based organic small molecule could be a very promising HTM candidate for highly efficient PSCs,and gives some significant insights for understanding intrinsic hot carriers transfer dynamics in device.

关键词： tetraphenylethene hole transporting material perovskite solar cells mobility hot carrier

Methyl and methane elimination in the gas phase reaction of zirconium atom with 2-butyne:A DFT study

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Chinese Chemical Letters 2010年第12期21卷 1501-1504页

作者： Tao Hong Li Chuan Ming Wang Xiao Guang xie Department of Chemistry Southwest Forestry University Kunming 650224 China Department of Biology Honghe University Menzi 661100 China Department of Chemistry Yunnan University Kunming 650091 China

The mechanisms for CH3- and CH_4-elimination in the gas phase reaction of ground-state Zr with 2-butyne has been investigated in detail using B3LYP *** the elimination of CH3,two mechanisms which are similar to those previously found for the reactions of Y and Zr with propyne are *** mechanism for the elimination of CH_4 was revealed as：Zr ＋ CH3C≡CCH_3→π-complex→TS（H-migration）→HZr-（H2CCC）-CH3→TS（C-C insertion）→（H2CCC）-HZr-CH3→TS（H-migration）→CH4＋ ZrC3H2.

关键词： Mechanism Zirconium 2-Butyne B3LYP

Cognitive mechanism related to line drawings and its applications in intelligent process of visual media： a survey

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Frontiers of Computer Science 2016年第2期10卷 216-232页

作者： Yongjin LIU Minjing YU Qiufang FU Wenfeng CHEN Ye LIU Lexing xie Tsinghua National Laboratory for Information Science and Technology Department of Computer Science and Technology Tsinghua University Beijing 100084 China State Key Laboratory of Brain and Cognitive Science Institute of Psychology Chinese Academy of Sciences Beijing 100101 China Research School of Computer Science The Australian National University Canberra 0200 Australia

Line drawings, as a concise form, can be recognized by infants and even chimpanzees. Recently, how the visual system processes line-drawings attracts more and more attention from psychology, cognitive science and computer science. The neuroscientific studies revealed that line drawings generate similar neural actions as color photographs, which give insights on how to efficiently process big media data. In this paper, we present a comprehensive survey on line drawing studies, including cognitive mechanism of visual perception, computational models in computer vision and intelligent process in diverse media applications. Major debates, challenges and solutions that have been addressed over the years are discussed. Finally some of the ensuing challenges in line drawing studies are outlined.

关键词： line drawings cognitive computation visual media intelligent process

Theoretical analysis of the electric potential and the electrostatic dust transport around the Shackleton crater in the Lunar south pole region

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Science China Earth Sciences 2023年第10期66卷 2278-2286页

作者： Chengxuan ZHAO Hong GAN Lianghai xie Yi WANG Yongjun WANG Jingyan HONG Science and Technology on Vacuum Technology and Physics Laboratory Lanzhou Institute of PhysicsChina Academy of Space TechnologyLanzhou730000China Space Environment and Payload Engineering Center Lanzhou Institute of PhysicsChina Academy of Space TechnologyLanzhou730000China Deep Space Exploration Laboratory Hefei230026China State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing100190China Joint Research and Development Center of Chinese Science Academy and Shen County Liaocheng252400China School of Transportation Lanzhou Jiaotong UniversityLanzhou730000China

In recent years,the Lunar south pole region(SPR)has become the focus of future explorations due to its special illumination condition and the possible water ice in permanently shadowed craters around *** Shackleton crater locates almost exactly at the Moon’s south pole and has become the hottest destination for several landing missions,including the Chang’E-7 ***,people still know little about the electric potential and the dust environment around this *** this paper,we develop an analytical model to study the surface potential and the electrostatic dust transport around the *** is found that the crater’s floor can be negatively charged due to the topographic shielding,and the surface potential is as low as-175 V on the leeward crater ***,a large number of charged dust grains can be emitted from the leeward crater wall,with a maximum height of about 10 km and a horizontal distance of about 40 km,which brings a local dust cloud around the *** the topographic shielding and the local dust cloud are qualitatively verified by a numerical simulation,in which a typical dust density of 10^(4)-10^(5)m^(-3)is found near the *** results are important to the environmental assessment for future explorations near the ***,the results are helpful to understand the surface charging and the electrostatic dust transport on the other airless bodies.

关键词： Lunar south pole Lunar crater Solar wind plasma Lunar dust Surface charging

Fabrication of quantum-sized Cd S-coated Ti O2 nanotube array with efficient photoelectrochemical performance using modified successive ionic layer absorption and reaction(SILAR) method

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Science Bulletin 2015年第14期60卷 1281-1286页

作者： Na Lu Yan Su Jingyuan Li Hongtao Yu xie Quan Key Laboratory of Industrial Ecology and Environmental Engineering Ministry of Education School of Environmental Science and Technology Dalian University of Technology Institute of Electrostatics and Special Power Dalian University of Technology Faculty of Chemical Environmental and Biological Science and Technology Dalian University of Technology

Quantum-sized CdS-coated TiO2 nanotube array （Q-CdS-TiO2 NTA） was fabricated by the modified successive ionic layer absorption and reaction method. Scanning electron microscope and transmission electron microscope images showed the regular structure of TiO2 NTA, where quantum-sized CdS （diameter 〈10nm） deposited on both the inside and outside of TiO2 nanotube wall. Fabrication conditions including immersing cycles, calcination temperature and drying process were well optimized, and the Q-CdS-TiO2 NTA and its photoelectrochemical （PEC） properties were characterized by X-ray fluorescence spectrometer, UV-Vis diffuse reflectance spectra and photovoltage. Distinct increases in visible light absorption and photocurrent were observed as the immersing cycle was increased from 5 to 20 times. The additional drying process accelerated the CdS crystal growth rate, and thus, the fabrication time could be shortened accordingly. Calcination temperature influenced the PEC property of Q-CdS-TiO2 NTA deeply, and the optimized calcination temperature was found as 500 ℃. As the Q-CdS-TiO2 NTA was fabricated under such condition, the visible photocurrent density increased to 2.8 mA/cm and the photovoltage between 350 and 480 nm was enhanced by 2.33 times than that without calcination. This study is expected to optimize Q-CdS-TiO2 NTA fabrication conditions for the purpose of improving its PEC performance.

关键词： Quantum-sized CdS TiO2 nanotubearray Photoelectrochemical property

Influence of the field humiture environment on the mechanical properties of 316L stainless steel repaired with Fe314

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Frontiers of Mechanical Engineering 2018年第4期13卷 513-519页

作者： Lianzhong ZHANG Dichen LI Shenping YAN Ruidong xie Hongliang QU State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Xi'an 710049 China

The mechanical properties of 316L stainless steel repaired with Fe314 under different temperatures and humidities without inert gas protection were studied. Results indicated favorable compatibility between Fe314 and 316L stainless steel. The average yield strength, tensile strength, and sectional contraction percentage were higher in repaired samples than in 316L stainless steel, whereas the elongation rate was slightly lower. The different conditions of humiture environment on the repair sample exerted minimal influence on tensile and yield strengths. The Fe314 cladding layer was mainly composed of equiaxed grains and mixed with randomly oriented columnar crystal and tiny pores or impurities in the tissue. Results indicated that the hardness value of Fe314 cladding layer under different humiture environments ranged within 419-451.1 HVo.2. The field humimre environment also showed minimal impact on the average hardness of Fe314 cladding layers. Furthermore, 316L stainless steel can be repaired through laser cladding by using Fe314 powder without inert gas protection under different temperatures and humidity environments.

关键词： laser cladding repaired performance tensile strength temperature and humidity environment

Contribution of black carbon to nonlinearity of sorption and desorption of acetochlor on sediment

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Frontiers of Environmental Science & Engineering 2009年第1期3卷 69-74页

作者： Jianqiu LIU Yaobin ZHANG Hong CHEN Yazhi ZHAO xie QUAN Key Laboratory of Industrial Ecology and Environmental Engineering Ministry of EducationSchool of Environmental and Biological Science and TechnologyDalian University of TechnologyDalian 116023China

In order to investigate the contribution of various black carbon(BC)contents to nonlinearity of sorption and desorption isotherms for acetochlor on sediment,equilibrium sorption and desorption isotherms were determined to measure sorption and desorption of acetochlor in sediment amended with various amounts of *** this paper,two types of BC referred to as BC400 and BC500 were prepared at 400℃ and 500℃,*** preparation temperature facilitated the formation of micropores on BC to enhance its sorption *** of the BC content obviously increased the sorption amount and reduced the desorption amount for *** the BC500 contents in total organic carbon(TOC)increased from 0 to 60%,Freundlich sorption coefficient(K_(f))increased from 4.07 to 35.74,and desorption hysteresis became gradually *** the content of BC in TOC was lower than 23%,the sorption isotherm had a significant linear correlation(p=0.05).In case of desorption,a significant nonlinear change could be observed when the content of BC was up to 13%.Increase of BC content in the sediment would result in shifting the sorption-desorption isotherms from linearity to nonlinearity,which indicated that contribution of BC to nonlinear adsorption fraction became gradually remarkable.

关键词： black carbon(BC) sorption desorption sediment

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XML与Web数据挖掘

商业研究 2005年第21期 206-208页

作者：谢兰云东北财经大学经济信息系辽宁大连116023

互联网时代,绝大多数信息都来自于Internet,数据挖掘的对象将更侧重于Web数据挖掘,但是Web页面上的信息并不适合进行数据挖掘。Web数据挖掘存在的种种问题,而XML的出现为解决这些问题提供了契机。

关键词： Web数据挖掘 XML 数据库

A comparison on the phytoremediation ability of triazophos by different macrophytes

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Journal of Environmental Sciences 2014年第2期26卷 315-322页

作者： Zhu Li Huiping Xiao Shuiping Cheng Liping Zhang Xiaolong xie Zhenbin Wu State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences University of the Chinese Academy of Sciences Wuhan Yangtze Business University Key Laboratory of Yangtze River Water Environment Ministry of Education Tongji University

The strategy of choosing suitable plants should receive great performance in phytoremediation of surface water polluted by triazophos （O,O-diethyl-O-（1-phenyl- 1,2,4-triazol-3-base） sulfur phosphate, TAP）, which is an organophosphorus pesticide widespread applied for agriculture in China and moderately toxic to higher animal and fish. The tolerance, uptake, transformation and removal of TAP by twelve species of macrophytes were examined in a hydroponic system and a comprehensive score （CS） of five parameters （relative growth rate （RGR）, biomass, root/shoot ratio, removal capacity （RC）, and bio-concentration factor （BCF）） by factor analysis was employed to screen the potential macrophyte species for TAP phytoremediation. The results showed that Thalia dealbata, Cyperus alternifolius, Canna indica and Acorus calamus had higher RGR values, indicating these four species having stronger growth capacity under TAP stress. The higher RC loading in Iris pseudacorus and Cyperus rotundus were 42.11 and 24.63μg/（g ***）, respectively. The highest values of BCF occurred in A. calamus （1.17）, and TF occurred in Eichhornia crassipes （2.14）. Biomass and root/shoot ratio of plant showed significant positive correlation with first-order kinetic constant of TAP removal in the hydroponic system, indicating that plant biomass and root system play important roles in remediation of TAP. Five plant species including C. alternifolius, A. calamus, T. dealbata, C. indica and Typha orientalis, which owned higher CS, would be potential species for TAP phytoremediation of contaminated water bodies.

关键词： pesticide removal capacity relative growth rate bio-concentration factor transfer factor root/shoot ratio factor analysis