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Nano Research 2023年第4期16卷 5572-5591页

作者： shufang wu Yongjun Liu College of Chemical Engineering Huaqiao UniversityXiamen 361021China

Double-metallic lead-free halide perovskites,Cs_(2)B^(I)B^(III)X_(6),sharing three-dimensional crystal structure,have been under the spotlight as the promising alternatives for the toxic and instable lead-based *** in Cs_(2)B^(I)B^(III)X_(6)motivates intense research into their colloidal nanocrystals(NCs).Recently,Cs_(2)B^(I)B^(III)X_(6)NCs have made great progress in the optical performance via alloying or doping,but there are still great challenges for optoelectronic *** this review,the latest advances of Cs_(2)B^(I)B^(III)X_(6)NCs in synthesis approaches,bandgap engineering,photoluminescence(PL)optimization,and applications are *** focus is put upon the composition-property relationships of Cs_(2)B^(I)B^(III)X_(6)NCs,which is approached by discussing the influences of composition variation on the electronic states,carrier dynamics,and optical *** challenges and the corresponding improving strategies in the development of high-effective and stable Cs_(2)B^(I)B^(III)X_(6)NCs for device applications are also *** is believed that this review can deepen the understanding on this burgeoning material system and shed light on their future research directions.

关键词： Cs_(2)B^(I)B^(III)X_(6)nanocrystals alloying/doping composition-property relationships improving strategies device applications

Effects of alfalfa coverage on runoff,erosion and hydraulic characteristics of overland flow on loess slope plots

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Frontiers of Environmental Science & Engineering 2011年第1期5卷 76-83页

作者： shufang wu Pute wu Hao FENG G.P.Merkley College of Water Resources and Architectural Engineering China Academy of Water-saving Agriculture on Arid RegionsNorthwest A&F UniversityYangling 712100China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of SciencesYangling 712100China Biological and Irrigation Engineering Department Utah State UniversityLoganUT 84116USA

An evaluation of the interactions between vegetation,overland and soil erosion can provide valuable insight for the conservation of soil and *** experiment was conducted to study water infiltration,runoff generation process,rate of sediment erosion,and hydrodynamic characteristics of overland flow from a sloping hillside with different draw-off discharges from alfalfa and control plots with 20°*** effect of alfalfa on runoff and sediment transport reduction was quantitatively *** was discussed for its ability to reduce the overland flow scouring force or change the runoff *** to the bare-soil plots,alfalfa plots generated a 1.77 times increase in infiltration ***,the down-slope water infiltration rate for the bare soil plots was higher than in the up-slope,while the opposite was found in the alfalfa *** addition,alfalfa had a significant effect on runoff and sediment *** comparison to the control,the runoff coefficient and sediment transportation rate decreased by 28.3%and 78.4%in the grass slope,*** runoff generated from the alfalfa and bare-soil plots had similar trends with an initial increase and subsequent leveling to a steady-state *** transport of sediment reduced with time as a consequence of the depletion of loose surface *** maximum sediment concentration was recorded within the first few minutes of each *** alfalfa plots had subcritical flow while the baresoil plots had supercritical flow,which indicate that the capability of the alfalfa slope for resisting soil erosion and sediment movement was greater than for bare soil ***,the flow resistance coefficient and roughness coefficient for the alfalfa plots were both higher than for the bare-soil plots,which indicate that overland flow in alfalfa plots had retarded and was blocked,and the flow energy along the runoff path had gradually ***,the ability to erode and transport sediment had de

关键词： alfalfa soil erosion runoff and sedimentation soil water infiltration overland flow hydrodynamic characteristics

Catalytic asymmetric(3+3)cycloaddition between different 2-indolylmethanols

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Science China Chemistry 2024年第8期67卷 2629-2636页

作者： Tianzhen Li Sijia Liu shufang wu Qi Cheng Qun Chen Yinchun Jiao Yuchen Zhang Feng Shi School of Petrochemical Engineering School of Materials ScienceEngineeringChangzhou UniversityChangzhou 213164China Research Center of Chiral Functional Heterocycles School of Chemistry and Materials ScienceJiangsu Normal UniversityXuzhou 221116China School of Chemistry and Chemical Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiang 453007China

The catalytic asymmetric(3+3)cycloaddition between different 2-indolylmethanols has been established,in which a series of chiral indole-fused six-membered heterocycles were constructed in high yields with excellent *** work not only has established the first catalytic asymmetric cycloaddition between different 2-indolylmethanols but also provided a powerful strategy for constructing enantioenriched indole-fused six-membered ***,biological evaluation discovered some products with promising antitumor ***,theoretical calculations performed on the reaction pathway and activation mode provide an in-depth understanding of this catalytic asymmetric(3+3)cycloaddition among different 2-indolylmethanols,which will advance the understanding of the chemistry of indolylmethanols.

关键词： asymmetric organocatalysis chiral phosphoric acid cycloaddition enantioselectivity 2-indolylmethanol

Check dam extraction from remote sensing images using deep learning and geospatial analysis:A case study in the Yanhe River Basin of the Loess Plateau,China

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Journal of Arid Land 2023年第1期15卷 34-51页

作者： SUN Liquan GUO Huili CHEN Ziyu YIN Ziming FENG Hao wu shufang Kadambot H M SIDDIQUE Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas Ministry of EducationNorthwest A&F UniversityYangling 712100China Institute of Water-Saving Agriculture in Arid Areas of China Northwest A&F UniversityYangling 712100China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling 712100China College of Natural Resources and Environment Northwest A&F UniversityYangling 712100China The UWA Institute of Agriculture and School of Agriculture&Environment The University of Western AustraliaPerth 6001Australia

Check dams are widely used on the Loess Plateau in China to control soil and water losses,develop agricultural land,and improve watershed *** information on the number and spatial distribution of check dams is critical for quantitatively evaluating hydrological and ecological effects and planning the construction of new ***,this study developed a check dam detection framework for broad areas from high-resolution remote sensing images using an ensemble approach of deep learning and geospatial ***,we made a sample dataset of check dams using GaoFen-2(GF-2)and Google Earth ***,we evaluated five popular deep-learning-based object detectors,including Faster R-CNN,You Only Look Once(version 3)(YOLOv3),Cascade R-CNN,YOLOX,and VarifocalNet(VFNet),to identify the best one for check dam ***,we analyzed the location characteristics of the check dams and used geographical constraints to optimize the detection ***,recall,average precision at intersection over union(IoU)threshold of 0.50(AP_(50)),IoU threshold of 0.75(AP_(75)),and average value for 10 IoU thresholds ranging from 0.50-0.95 with a 0.05 step(AP_(50-95)),and inference time were used to evaluate model *** the five deep learning networks could identify check dams quickly and accurately,with AP_(50-95),AP_(50),and AP_(75)values higher than 60.0%,90.0%,and 70.0%,respectively,except for *** VFNet had the best performance,followed by *** proposed framework was tested in the Yanhe River Basin and yielded promising results,with a recall rate of 87.0%for 521 check ***,the geographic analysis deleted about 50%of the false detection boxes,increasing the identification accuracy of check dams from 78.6%to 87.6%.Simultaneously,this framework recognized 568 recently constructed check dams and small check dams not recorded in the known check dam survey *** extraction results will support efficient watershed management and

关键词： check dam deep learning geospatial analysis remote sensing Faster R-CNN Loess Plateau

Ephemeral gully recognition and accuracy evaluation using deep learning in the hilly and gully region of the Loess Plateau in China

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International Soil and Water Conservation Research 2022年第3期10卷 371-381页

作者： Boyang Liu Biao Zhang Hao Feng shufang wu Jiangtao Yang Yufeng Zou Kadambot H.M.Siddique Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas Ministry of EducationNorthwest A&F UniversityYangling712100China Institute of Water Saving Agriculture in Arid Areas of China Northwest A&F UniversityYangling712100China College of Water Resources and Architectural Engineering Northwest A&F UniversityYangling712100China Department of Foreign Languages Northwest A&F UniversityYangling712100China The UWA Institute of Agriculture and School of Agriculture&Environment The University of Western AustraliaPerthWA6001Australia

Ephemeral gullies are widely distributed in the hilly and gully region of the Loess Plateau and play a unique role in the slope gully erosion *** and accurate identification of ephemeral gullies impacts the distribution law and development trend of soil erosion on the Loess *** learning algorithms can quickly and accurately process large data samples that recognize ephemeral gullies from remote sensing ***,we investigated ephemeral gullies in the Zhoutungou watershed in the hilly and gully region of the Loess Plateau in China using satellite and unmanned aerial vehicle images and combined a deep learning image semantic segmentation model to realize automatic recognition and feature *** Accuracy,Precision,Recall,F1value,and AUC,we compared the ephemeral gully recognition results and accuracy evaluation of U-Net,R2U-Net,and SegNet image semantic segmentation *** SegNet model was ranked first,followed by the R2U-Net and U-Net models,for ephemeral gully recognition in the hilly and gully region of the Loess *** ephemeral gully length and width between predicted and measured values had RMSE values of 6.78 m and 0.50 m,respectively,indicating that the model has an excellent recognition *** study identified a fast and accurate method for ephemeral gully recognition in the hilly and gully region of the Loess Plateau based on remote sensing images to provide an academic reference and practical guidance for soil erosion monitoring and slope and gully management in the Loess Plateau region.

关键词： Deep learning Remote sensing image Ephemeral gully recognition Loess plateau Image semantic segmentation Accuracy evaluation

X-ray-ultraviolet–visible-near-infrared photoresponsesrealized in a lead-free hybrid perovskite ferroelectricthrough light-induced ferro-pyro-phototronic effect

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InfoMat 2024年第10期6卷 96-107页

作者： Dongying Fu Yanli Ma shufang wu Lin Pan Qi Wang Ruifang Zhao Xian-Ming Zhang Junhua Luo Institute of Crystalline Materials Key Laboratory of Quantum Optics and Quantum Optics DevicesShanxi UniversityKey Laboratory of Materials for Energy Conversion and Storage of Shanxi ProvinceTaiyuanShanxithe People's Republic of China College of Chemistry Key Laboratory of Interface Science and Engineering in Advanced MaterialMinistry of EducationTaiyuan University of TechnologyTaiyuanShanxithe People's Republic of China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhouFujianthe People's Republic of China

Due to the built-in electric field induced by spontaneous polarization in hybridperovskite (HP) ferroelectrics, the devices based on them exhibit excellent performancein self-powered photodetection. However, most of the self-poweredphotodetector are made of lead-based HP ferroelectrics and have a relativelynarrow photoresponse waveband. Although lead-free HPs solve the problem oflead toxicity, their optoelectronic performance is inferior to that of lead-basedHPs and photoresponse waveband is limited by its optical band gap, whichhinders their further application. To solve this problem, herein, a lead-free HPferroelectric (HDA)BiI5 (HDA is hexane-1,6-diammonium) with large spontaneouspolarization shows an enhanced photocurrent and achieves x-ray-ultraviolet–visible-near-infrared (x-ray-UV–Vis–NIR) photoresponse through theferro-pyro-phototronic (FPP) effect. The ferroelectric, pyroelectric, and photovoltaiccharacteristics coupled together in a single-phase (HDA)BiI5 ferroelectricis an effective way to improve the performance of the devices. What isparticularly attractive is that the FPP effect not only improves the optoelectronicperformance of (HDA)BiI_(5), but also achieves broadband photoresponsesbeyond its optical absorption range. Especially, the current boosting with anexceptional contrast of 1100% and 2400% under 520 and 637 nm, respectively,which is associated with FPP effect. Meanwhile, single crystal self-poweredphotodetector based on (HDA)BiI5 also exhibit significant FPP effects evenunder high-energy x-ray, which owns an outstanding sensitivity of 170.7 μCGy^(-1) cm^(-2) and a lower detection limit of 266 nGy s^(-1) at 0 V bias. Therefore, it is of great significance to study the coupling of multiple physical effects andimprove device performance based on lead-free HP ferroelectrics.

关键词： broadband photoresponse ferro-pyro-phototronic effect hybrid perovskite lead-free ferroelectric self-powered photodetection

Lewis acid-catalyzed[4+2]cycloaddition of 3-alkyl-2-vinylindoles withβ,γ-unsaturatedα-ketoesters

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Green Synthesis and Catalysis 2022年第1期3卷 84-88页

作者： Yuwen Sun Zhaoshan Wang shufang wu Yuchen Zhang Feng Shi School of Chemistry and Materials Science Jiangsu Normal UniversityXuzhou 221116China

A Lewis acid-catalyzed[4+2]cycloaddition of 3-alkyl-2-vinylindoles withβ,γ-unsaturatedα-ketoesters has been established in the presence of Sc(OTf)3,which afforded a series of indole-containing pyran derivatives in generally good yields(up to 90%yield)with excellent diastereoselectivities(up to >95:5 dr)under mild *** approach not only enriches the chemistry of 3-alkyl-2-vinylindoles,but also has provided an atom-economic method for the synthesis of indole-containing pyran derivatives with potential bioactivity.

关键词： Lewis acid catalysis [4+2]Cycloaddition 3-Alkyl-2-vinylindole β,γ-Unsaturatedα-ketoester Indole-containing pyran

Therapy and mechanism of natural polysaccharides for atopic dermatitis treatment

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Food Science and Human Wellness 2024年

作者： Wenjie Wang Lijun Shao Xiao Jiang Qiulu Chu Jian Xiao shufang wu Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources， Nanjing Forestry University College of Light Industry and Food Engineering， Nanjing Forestry University Department of Forest Biomaterials， North Carolina State University

Atopic dermatitis (AD) is a common multifactorial skin disease characterized by chronic inflammation， unbearable itching， and significant physical and mental burden on patients. In recent years， there has been extensive studied on the use of natural polysaccharides in anti-inflammatory therapy， due to their low toxicity and multi-target pharmacological activity. The unique biological activities of polysaccharides from natural sources as functional food additives and cosmeceuticals present a new option for the treatment of AD. This review aims to summarize the pathogenesis of AD， the therapeutic effects， and the mechanisms of natural polysaccharides， as well as discuss the limitations and prospects of these compounds in the treatment of AD. The insights provided in this review can serve as references and inspiration for the development of applications of natural polysaccharides in the treatment of AD.

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大学英语教师自主性差异研究——以新手教师与熟手教师为例

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外语教学 2011年第6期32卷 70-73页

作者：吴书芳南阳理工学院外语系河南南阳473004

本文以中国大学英语教学改革为背景,旨在探索新手与熟手教师自主水平,通过差异对比反映中国教师自主的现状,并据此提出促进教师自主发展的可行性策略,以促进不同阶段教师在专业发展中自主能力的培养,为教师教育和发展提供参考。

关键词：新手教师熟手教师教师自主对比研究

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基于映射法的曲面自适应网格生成

兵工学报 2000年第1期21卷 50-52页

作者：吴淑芳长春光学精密机械学院吉林长春130022

板壳成形数值模拟过程中用自适应网格不仅可以实现以尽可能少的计算量获得指定精度要求的解 ,更重要的是可以提高解的精度。而曲面自适应网格自动生成技术国内外都刚开始研究 ,目前没有很好的方法。本文首次基于映射法在参数区域生成自... 详细信息

板壳成形数值模拟过程中用自适应网格不仅可以实现以尽可能少的计算量获得指定精度要求的解 ,更重要的是可以提高解的精度。而曲面自适应网格自动生成技术国内外都刚开始研究 ,目前没有很好的方法。本文首次基于映射法在参数区域生成自适应网格 ,然后映射到空间 ,用空间曲面的曲率及有限元计算误差估计来控制参数区域中的自适应网格生成。

关键词：曲面网格自适应性映射法 ADAPTIVE MESH GENERATION METHODS