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Charge-carrier photogeneration and extraction dynamics of polymer solar cells probed by a transient photocurrent nearby the regime of the space charge-limited current

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Frontiers of Chemical Science and Engineering 2021年第1期15卷 164-179页

作者： Boa Jin Hyunmin Park Yang Liu Leijing Liu Jongdeok An Wenjing Tian Chan im Department of Chemistry Konkuk UniversitySeoul 05029Republic of Korea State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China

To understand the complex behaviors of photogenerated charge carriers within polymer-based bulk-heterojunction-type solar cells,the charge-carrier photogeneration and extraction dynamics are simultaneously estimated using a transient photocurrent technique under various external-bias voltages,and a wide range of excitation intensities are *** this purpose,conventional devices with 80 nm thick active layers consisting of a blend of representative P3HT and PTB7 electron-donating polymers and proper electron-accepting fullerene derivatives were *** the correction for the saturation behavior at a high excitation-intensity range nearby the regime of the space charge-limited current,the incident-photon-density-dependent maximum photocurrent densities at the initial peaks are discussed as the proportional measures of the charge-carrier-photogeneration *** comparing the total number of the extracted charge carriers to the total number of the incident photons and the number of the initially photogenerated charge carriers,the external quantum efficiencies as well as the extraction quantum efficiencies of the charge-carrier collection during a laser-pulse-induced transient photocurrent process were ***,the charge-carrier concentration-dependent mobility values were obtained,and they are discussed in consideration of the additional influences of the charge-carrier losses from the device during the charge-carrier extraction that also affects the photocurrent-trace shape.

关键词： charge-carrier photogeneration transient photocurrent polymer solar cells charge-carrier extraction space charge-limited current

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Letter to the Editor

Advances in Enzyme research 2013年第4期1卷 77-78页

作者： Amosy E. M’koma School of Medicine Meharry Medical College Nashville USA

Advances in Enzyme

关键词： Letter to the Editor Advances in Enzyme research (AEr)

Hyperoxia accelerates progression of hepatic fibrosis by up-regulation of transforming growth factor-β expression

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World Journal of Gastroenterology 2014年第11期20卷 3011-3017页

作者： Sang Hwa Lee Sung-im Do Hyun-Soo Kim Department of Pathology Aerospace Medicine Research CenterAerospace Medical CenterRepublic of Korea Air ForceChungcheongbuk-do 363-849South Korea Department of Pathology Kangbuk Samsung HospitalSungkyunkwan University School of MedicineSeoul 110-746South Korea

Aim: To investigate the effect of hypoxia or hyperoxia on the progression of hepatic fibrosis and to examine the role of transforming growth factor-β (TGF-β) in the livers of rats exposed to hypoxic or hyperoxic con... 详细信息

关键词： Hepatic fibrosis, Cirrhosis, Hypoxia, Hyperoxia, Transforming growth factor-β

Optimization of ionic liquid-based microwave-assisted extraction of polyphenolic content from Peperomia pellucida (L) kunth using response surface methodology

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Asian Pacific Journal of Tropical Biomedicine 2017年第7期7卷 660-665页

作者： Islamudin Ahmad Arry Yanuar Kamarza Mulia Abdul Mun'im Department of Pharmaceutical Sciences Faculty of Pharmacy Mulawarman University Samarinda East Kalimantan Indonesia Department of Pharmaceutical Sciences Faculty of Pharmacy Universitas Indonesia Depok 16424 West Java Indonesia Department of Chemical Engineering Faculty of Engineering Universitas Indonesia Depok 16424 West Java Indonesia

Objective: To optimize the ionic liquid based microwave-assisted extraction (IL-MAE) of polyphenolic content from Peperomia pellucida (L) Kunth. Methods: The IL-MAE factors as experimental design parameters, including microwave power, extraction time, ionic liquid concentration, and liquid–solid ratio had been involved. response surface methodology and Box–Behnken design were used to obtain predictive model (multivariate quadratic regression equation) and optimization of the extraction process. The response surface was analyzed by using the yields of total polyphenolic content as response value. results: Based on the obtained results the optimum extraction condition, including microwave power of 30% Watts, extraction time of 18.5 min, the ionic liquid concen-tration of 0.79 mol/L, and the liquid–solid ratio of 10.72 mL/g 1-Buthyl-3-methylimidazolium tetrafluoroborate ([bmim]BF4) as a solvent was selected. The regression model was obtained to predicts the yields from Peperomia pellucida:Y = 30.250 – 1.356X1 + 2.655X2 + 2.252X3 – 0.565X4 + 0.990 X1X3 – 8.172 X1X4 – 3.439 X3X4 – 4.178 X12 – 3.210 X32 – 6.786 X42 – 7.290 X12X3 + 5.575 X1X32 – 4.843 X32X4 with r2 = 0.82519. Scale-up confirmation test was obtained the maximum yields of total polyphenolics content with the amount of 31.1725μg GAE/g. Conclusions: The IL-MAE method produced a higher extraction polyphenolic and performed rapidly, easily and efficiently.

关键词： Peperomia pellucida (L) Kunth 1-buthyl-3-methylimidazolium Tetrafluoroborate response surface methodology Box–Behnken design Polyphenolic content

Information Extraction Based on Multi-turn Question Answering for Analyzing Korean research Trends

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Computers, Materials & Continua 2023年第2期74卷 2967-2980页

作者： Seongung Jo Heung-Seon Oh Sanghun im Gibaeg Kim Seonho Kim School of Computer Science and Engineering KOREATECHCheonan31253Korea Korea Institute of Science and Technology Information KISTIDaejeon34141Korea

Analyzing research and Development(r&D)trends is important because it can influence future decisions regarding r&D *** typical trend analysis,topic or technology taxonomies are employed to compute the popularities of the topics or codes over *** it is simple and effective,the taxonomies are difficult to manage because new technologies are introduced ***,recent studies exploit deep learning to extract pre-defined targets such as problems and *** on the recent advances in question answering(QA)using deep learning,we adopt a multi-turn QA model to extract problems and solutions from Korean r&D *** the previous research,we use the reports directly and analyze the difficulties in handling them using QA style on Information Extraction(IE)for sentence-level benchmark *** investigating the characteristics of Korean r&D,we propose a model to deal with multiple and repeated appearances of targets in the ***,we propose a model that includes an algorithm with two novel modules and a prompt.A newly proposed methodology focuses on reformulating a question without a static template or pre-defined *** show the effectiveness of the proposed model using a Korean r&D report dataset that we constructed and presented an in-depth analysis of the benefits of the multi-turn QA model.

关键词： Natural language processing information extraction question answering multi-turn Korean research trends

Long-lasting photoluminescence quantum yield of cesium lead halide perovskite-type quantum dots

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Frontiers of Chemical Science and Engineering 2021年第1期15卷 187-197页

作者： Yonghyun Kim Huiwen Liu Yi Liu Boa Jin Hao Zhang Wenjing Tian Chan im Department of Chemistry Konkuk UniversitySeoul 05029Korea State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China

Cesium lead halide perovskite(CsPbX_(3),X=Cl,Br,I)quantum dots(QDs)and their partly Mn^(2+)-substituted QDs(CsPb1–xMnxX3)attract considerable attention owing to their unique photoluminescence(PL)*** two types of QDs,having different PL decay dynamics,needed to be further investigated in a form of aggregates to understand their solid-state-induced exciton dynamics in conjunction with their behaviors upon degradation to achieve practical applications of those promising ***,thus far,these QDs have not been sufficiently investigated to obtain deep insights related to the long-term stability of their PL properties as aggregated ***,in this study,we comparatively examined CsPbX_(3)-and CsPb1–xMnxX_(3)-type QDs stocked for>50 d under dark ambient conditions by using excitation wavelength-dependent PL quantum yield and time-resolved PL *** investigations were performed with powder samples in addition to solutions to determine the influence of the inter-QD interaction of the aged QD aggregates on their radiative *** turns out that the Mn^(2+)-substituted QDs exhibited long-lasting PL quantum efficiencies,while the unsubstituted CsPbX_(3)-type QDs exhibited a drastic reduction of their PL *** the obtained PL traces were clearly sensitive to the sample *** is discussed with the possible interaction depending on the size and distance of the QD aggregates.

关键词： quantum dots cesium lead halide perovskite time-resolved photoluminescence PL quantum yield QD aggregates

WrA-Net:Wide receptive Field Attention Network for Motion Deblurring in Crop and Weed image

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Plant Phenomics 2023年第2期5卷 174-194页

作者： Chaeyeong Yun Yu Hwan Kim Sung Jae Lee Su Jin im Kang ryoung Park Division of Electronics and Electrical Engineering Dongguk University30 Pildong-ro 1-gilJung-guSeoul 04620Republic of Korea

Automatically segmenting crops and weeds in the image input from cameras accurately is essential in various agricultural technology fields,such as herbicide spraying by farming robots based on crop and weed segmentation ***,crop and weed images taken with a camera have motion blur due to various causes(e.g.,vibration or shaking of a camera on farming robots,shaking of crops and weeds),which reduces the accuracy of crop and weed ***,robust crop and weed segmentation for motion-blurred images is ***,previous crop and weed segmentation studies were performed without considering motion-blurred *** solve this problem,this study proposed a new motion-blur image restoration method based on a wide receptive field attention network(WrA-Net),based on which we investigated improving crop and weed segmentation accuracy in motion-blurred ***-Net comprises a main block called a lite wide receptive field attention residual block,which comprises modified depthwise separable convolutional blocks,an attention gate,and a learnable skip *** conducted experiments using the proposed method with 3 open databases:Bonirob,crop/weed field image,and rice seedling and weed *** to the results,the crop and weed segmentation accuracy based on mean intersection over union was 0.7444,0.7741,and 0.7149,respectively,demonstrating that this method outperformed the state-of-the-art methods.

关键词： Net shaking image

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： r.A.JAFArI-TALOOKOLAEI H.GHANDVAr E.JUMAEV S.KHATIr T.CUONG-LE School of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and Science Center for Engineering Application and Technology Solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. The strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. Subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

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Siberian silkmoth outbreaks surpassed geoclimatic barrier in Siberian Mountains

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Journal of Mountain Science 2020年第8期17卷 1891-1900页

作者： KHArUK Viacheslav I. im Sergei T. SOLDATOV vla.imir V. Sukachev Institute of Forest Federal Scientific CenterRussian Academy of ScienceSiberian BranchAcademgorodok 50/28Krasnoyarsk660036 Russia Siberian Federal University Svobodny str.79Krasnoyarsk660041 Russia reshetnev Siberian State University of Science and Technology Krasnoyarsky rabochy str.31Krasnoyarsk660014 Russia russian Center of Forest Protection Academgorodok 50A/2Krasnoyarsk660036 Russia

Siberian silkmoth(SSM,Dendrolimus sibiricus Tschetv.)is the most important defoliator of Siberian pine(Pinus sibirica Du Tour)and fir(Abies sibirica Ledeb.)***-induced SSM outbreaks are one of the major driving factors of successions within the taiga *** is suggested that climate change impacted the SSM range and life *** analyzed the migration of alpine and northerly SSM outbreak boundaries in Siberia and the impact of the climate variables and topography on the outbreak *** used time-series scenes(multispectral data,and vegetation indexes EVI and NDII)in combination with field studies,climate variables,and GIS *** found that SSM outbreaks in the area of alpine boundary shifted about 370 m uphill since the mid of *** outbreak onset was promoted by increased dryness and active temperatures and decreased root zone moisture content in the spring-early summer *** terrain topography strongly affected SSM outbreak onset and ***,the outbreak was located at the middle elevations on the gentle concave southeastern slopes,which are the favorable insect habitats between *** the outbreak expanded uphill and downhill,to steeper slopes,and both concave and convex *** with elevation range expansion,SSM surpassed its northern historical outbreak boundary:the potential outbreaks’boundary moved about 300 km *** warming contributes to SSM migration into former outbreak free conifer stands located in highlands and at northern latitudes.

关键词： Insect outbreaks remote sensing monitoring Insect ranges expansion Siberian silkmoth Forest health Conifer mortality