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Nonlinear relationship between urban form and transport CO_(2)emissions:Evidence from Chinese cities based on machine learning

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Journal of Geographical Sciences 2024年第8期34卷 1558-1588页

作者： LI linna DENG Zilin HUANG Xiaoyan Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Northwest Land and Resources Research Center Global Regional and Urban Research InstituteShaanxi Normal UniversityXi'an 710119China

Reducing carbon emissions from the transport sector is essential for realizing the carbon neutrality goal in *** substantial studies on the influence of urban form on transport cO_(2)emissions,most of them have treated the effects as a linear process,and few have studied their nonlinear *** research focused on 274 Chinese cities in 201. and applied the gradient-boosting decision tree(GBDT)model to investigate the nonlinear effects of four aspects of urban form,including compactness,complexity,scale,and fragmentation,on urban transport CO_(2)*** was found that urban form contributed 20.48%to per capita transport CO_(2)emissions(PTCEs),which is less than the contribution of socioeconomic development but more than that of transport *** contribution of urban form to total transport CO_(2)emissions(TCEs)was the lowest,at 1..3%.In particular,the effect of compactness on TCEs was negative within a threshold,while its effect on PTCEs showed an inverted U-shaped *** effect of complexity on PTCEs was positive,and its effect on TCEs was *** effect of scale on TCEs and PTCEs was positive within a threshold and negative beyond that *** effect of fragmentation on TCEs was also nonlinear,while its effect on PTCEs was positively *** results show the complex effects of the urban form on transport CO_(2)***,strategies for optimizing urban form and reducing urban transport carbon emissions are recommended for the future.

关键词： urban form transport CO,emissions nonlinear effect sustainable transport gradient-boosting decision treemodel

Hole-Transporting Materials with Rational Combination of Pyridine and Dibenzo[a,c]phenazine as Electron Acceptor for Dopant-Free Perovskite Solar Cells

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Chinese Journal of Chemistry 2024年第10期42卷 1100-1106页

作者： Weidong Ling Fei Wu Wentao Yuan linna Zhu Qianqian Li Zhen Li Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials Department of ChemistryWuhan UniversityWuhanHubei 430072China Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energy Faculty of Materials&EnergySouthwest UniversityChongqing400715China TaiKang Center for Life and Medical Sciences Wuhan UniversityWuhanHubei 430072China

Perovskite solar cells(PSCs)have been proven to be a promising option for photovoltaic *** the aim to achieve efficient and stable PSCs,it is essential to explore dopant-free hole-transporting materials(HTMs)with high hole ***,HTMs bearing electron donor(D)-electron acceptor(A)-electron donor(D)structures have been constructed with strong intramolecular charge transfer(ICT)effect,based on rational combination of dibenzo[a,c]phenazine and pyridine as electronic acceptors and anchoring groups to perovskite ***,high hole mobility(7.31.1.^(-5) cm^(2)·V^(-1.·s^(-1.)and photoelectric conversion efficiency(20.45%)have been achieved by dopant-free DPyP-based *** afforded an efficient way to design HTMs with high hole mobility by adjustment of molecular configurations and electronic property of conjugated systems.

关键词： Perovskite solar cell Charge transfer Donor-acceptor systems Energy conversion Hole mobility

Low-cost dopant-free fluoranthene-based branched hole transporting materials for efficient and stable n-i-p perovskite solar cells

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Chinese Chemical Letters 2024年第10期35卷 187-193页

作者： Xinyu Yu Fei Wu Xianglang Sun linna Zhu Baoyu Xia Zhong'an Li Key Laboratory for Material Chemistry of Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energy Faculty of Materials&EnergySouthwest UniversityChongqing 400715China

It has been widely recognized that hole transporting materials(HTMs)play a key role in the rapid progress of perovskite solar cells(PVSCs).However,common organic HTMs such as spiro-OMe TAD not only suffer from high synthetic costs,but also usually require the additional chemical doping process to improve their hole transport ability,which unfortunately induces the terrible stability ***,it is urgent to develop low-cost dopant-free HTMs for efficient and stable *** this work,we have successfully developed a new class of efficient dopant-free fluoranthene-based HTMs(TPF1.5)with quite low lab synthetic costs by combining donor-acceptor and branched structure *** detailed structure-property study revealed that tuning the twisted arms at different substitution sites would regulate the intermolecular interactions and film-forming ability,thereby significantly affecting the performance of the *** applying these HTMs in conventional PVSCs,the dopant-free TPF1.based devices not only achieved the best efficiency of 21.76%,which is comparable to that of the doped spiro-OMeTAD control devices,but also showed much better operational stability,which maintained over 87%of the initial efficiency under maximum power point tracking after 1.38 h.

关键词： Perovskite solar cells Holetransporting materials Dopant-free Fluoranthene Low-cost

A Normalizing Flow-Based Bidirectional Mapping Residual Network for Unsupervised Defect Detection

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Computers, Materials & Continua 2024年第2期78卷 1631-1648页

作者： Lanyao Zhang Shichao Kan Yigang Cen Xiaoling Chen linna Zhang Yansen Huang School of Mechanical Engineering Guizhou UniversityGuiyang550025China School of Computer Science and Engineering Central South UniversityChangsha410083China School of Computer and Information Technology Beijing Jiaotong UniversityBeijing100044China College of Civil Engineering Guizhou UniversityGuiyang550025China Guizhou Lianjian Civil Engineering Quality Inspection Monitoring Center Co. Ltd.Guiyang550025China

Unsupervised methods based on density representation have shown their abilities in anomaly detection,but detection performance still needs to be ***,approaches using normalizing flows can accurately evaluate sample distributions,mapping normal features to the normal distribution and anomalous features outside ***,this paper proposes a Normalizing Flow-based Bidirectional Mapping Residual Network(NF-BMR).It utilizes pre-trained Convolutional Neural Networks(CNN)and normalizing flows to construct discriminative source and target domain feature ***,to better learn feature information in both domain spaces,we propose the Bidirectional Mapping Residual Network(BMR),which maps sample features to these two spaces for anomaly *** two detection spaces effectively complement each other’s deficiencies and provide a comprehensive feature evaluation from two perspectives,which leads to the improvement of detection *** experimental results on the MVTec AD and DAGM datasets against the Bidirectional Pre-trained Feature Mapping Network(B-PFM)and other state-of-the-art methods demonstrate that the proposed approach achieves superior *** the MVTec AD dataset,NF-BMR achieves an average AUROC of 98.7%for all 1. ***,it achieves 1.0%optimal detection performance in five *** the DAGM dataset,the average AUROC across ten categories is 98.7%,which is very close to supervised methods.

关键词： Anomaly detection normalizing flow source domain feature space target domain feature space bidirectional mapping residual network

Identifying multidisciplinary problems from scientific publications based on a text generation method

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Journal of Data and Information Science 2024年第3期9卷 213-237页

作者： Ziyan Xu Hongqi Han linna Li Junsheng Zhang Zexu Zhou Institute of Scientific and Technical Information of China Beijing 100038China

Purpose:A text generation based multidisciplinary problem identification method is proposed,which does not rely on a large amount of data ***/methodology/approach:The proposed method first identifies the research objective types and disciplinary labels of papers using a text classification technique;second,it generates abstractive titles for each paper based on abstract and research objective types using a generative pre-trained language model;third,it extracts problem phrases from generated titles according to regular expression rules;fourth,it creates problem relation networks and identifies the same problems by exploiting a weighted community detection algorithm;finally,it identifies multidisciplinary problems based on the disciplinary labels of ***:Experiments in the“Carbon Peaking and Carbon Neutrality”field show that the proposed method can effectively identify multidisciplinary research *** disciplinary distribution of the identified problems is consistent with our understanding of multidisciplinary collaboration in the *** limitations:It is necessary to use the proposed method in other multidisciplinary fields to validate its *** implications:Multidisciplinary problem identification helps to gather multidisciplinary forces to solve complex real-world problems for the governments,fund valuable multidisciplinary problems for research management authorities,and borrow ideas from other disciplines for ***/value:This approach proposes a novel multidisciplinary problem identification method based on text generation,which identifies multidisciplinary problems based on generative abstractive titles of papers without data annotation required by standard sequence labeling techniques.

关键词： Problem identification Multidisciplinary Text generation Text classification

Interfacial modification using the cross-linkable tannic acid for highly-efficient perovskite solar cells with excellent stability

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Journal of Energy Chemistry 2024年第4期91卷 236-244页

作者： Xing Gao Lirong Rong Fei Wu Yen-Hung Lin Ye Zeng Junhong Tan Rongxing He Cheng Zhong linna Zhu Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energy School of Materials&EnergySouthwest UniversityChongqing 400715China Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Department of ChemistryWuhan UniversityWuhan 430072HubeiChina Key Laboratory of Luminescence Analysis and Molecular Sensing Ministry of EducationSchool of Chemistry and Chemical EngineeringSouthwest UniversityChongqing 400715China Department of Electronic and Computer Engineering The Hong Kong University of Science and TechnologyClear Water BayKowloon 999077Hong KongChina State Key Laboratory of Advanced Displays and Optoelectronics Technologies The Hong Kong University of Science and TechnologyClear Water BayKowloon 999077Hong KongChina

Although the performance of perovskite solar cells(PSCs)has been dramatically increased in recent years,stability is still the main obstacle preventing the PSCs from being *** device instability can be caused by a variety of reasons,including ions diffusion,surface and grain boundary defects,*** this work,the cross-linkable tannic acid(TA)is introduced to modify perovskite film through post-treatment *** numerous organic functional groups(–OH and C=O)in TA can interact with the uncoordinated Pb^(2+)and I^(-)ions in perovskite,thus passivating defects and inhibiting ions *** addition,the formed TA network can absorb a small amount of the residual moisture inside the device to protect the perovskite ***,TA modification regulates the energy level of perovskite,and reduces interfacial charge ***,following TA treatment,the device efficiency is increased significantly from 21.31.to 23.1.%,with a decreased hysteresis ***,the treated device shows excellent air,thermal,and operational *** light of this,the readily available,inexpensive TA has the potential to operate as a multipurpose interfacial modifier to increase device efficiency while also enhancing device stability.

关键词： Tannic acid Defect passivation lons diffusion Hydrophilic Stability Perovskite solar cells

Spatio-temporal evolution and topographic gradient effect of land use and ecosystem service value in the Lhasa River Basin

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Journal of Mountain Science 2024年第6期21卷 2059-2074页

作者： ZHOU Jianwei FENG Bin WU Hua XU Tong CHEN linna ZHAO Xinyong GUO Qiyun LI Jiatong ZHANG Chenguang ZHU Kangcheng KONG Yuzhong School of Ecology and Environment Tibet UniversityLhasa 850000China School of Engineering Tibet UniversityLhasa 850000China Joint Laboratory of Plateau Surface Remote Sensing Tibet UniversityLhasa 850000China

The Lhasa River Basin forms an essential human settlement area in the southern part of the Qinghai-Tibet *** study employed ecosystem service value(ESV)evaluation model,terrain gradient grading,and Geodetector to analyze land use and ESV in the Lhasa River Basin from 1.85 to *** findings reveal that:(1.From 1.85 to 2020,grassland was the dominant land *** was a trend of grassland reduction and the expansion of other land types.(2)ESV has increased over the research period(with a total increase of 0.84%),with higher values in the southeast and lower values in the *** contributed the most to ESV,and climate regulation and hydrological regulation were the ecosystem services that contribute the most to ESV.(3)Natural factors like NDVI and altitude,as well as economic factors like population density and distance from roads,influenced the spatial differentiation of ESV,the explanatory power of NDVI reached up to *** interaction between factors had a greater impact than individual *** research results can provide theoretical support for national spatial planning and ecological environment protection in the Lhasa River Basin and other similar areas.

关键词： Ecosystem services value Land use Terrain gradient effect Lhasa River Basin Driving factors

Microencapsulated Lactobacillus plantarum promotes intestinal development through gut colonization of layer chicks

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Animal Nutrition 2024年第3期18卷 1-16页

作者： Yaoming Cui Yanxia Liu Jing Yang Haitao Duan Peng Wang linna Guo Yanjiao Guo Suying Li Yating Zhao Jinrong Wang Guanghai Qi Junjun Guan School of Biological Engineering Henan University of TechnologyZhengzhouHenan 450001China College of Animal Science and Technology Henan University of Animal Husbandry and EconomyZhengzhouHenan 450046China Feed Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China

The effects of Lactobacillus plantarum in microencapsulation(LPM)on intestinal development in layer chicks were investigated in this study,as well as the colonization of *** in the gut.A total of 480 healthy Hy-Line Brown layer chicks at 0 d old were randomly divided into 4 groups(8 replicates each treatment),and the diets of these birds were supplemented with nothing(control),***(0.02 g/kg feed;1.9 CFU/kg feed),LPM(1.0 g/kg feed;1.9 CFU/kg feed)and wall material of LPM(WM;0.98 g/kg feed),*** to control,LPM improved growth performance and intestinal development of layer chicks,evidenced by significantly increased body weight,average daily gain,average daily feed intake,villus height,villus height/crypt depth,as well as weight and length of the duodenum,jejunum and ileum(P<0.05).These results could be attributed to the increased colonization of *** in the gut,which was verified by significant increases in lactic acid content,viable counts in chyme and mucosa(P<0.05),as well as a visible rise in number of strains labeled with fluorescein ***,the relative abundances of Lactobacillus and Bifidobacterium significantly increased in response to microencapsulated *** supplementation(P<0.05),accompanied by the significant up-regulation of colonization related genes(P<0.05),encoding solute carrier family,monocarboxylate transporter,activin A receptor,succinate receptor and secretogranin *** sum up,microencapsulated *** supplementation promoted intestinal development,which could be attributed to the enhancement of *** colonization in the intestine through the mutual assistance of Bifidobacterium and interactions with colonization related transmembrane proteins.

关键词： Intestinal development Colonization Microbiota Layer chick Lactobacillus plantarum

扩压式自泵送流体动压机械密封性能分析及双目标优化研究

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摩擦学学报（中英文） 2024年第7期44卷 947-959页

作者：王琳娜孙见君南京林业大学机械电子工程学院江苏南京210037

泄漏率和开启力是在研究非接触式机械密封性能需要考虑的2个重要指标.目前针对非接触式机械密封的结构优化研究,仅限于固定内径的密封环,优化结果缺乏通用性.以新型扩压式自泵送流体动压机械密封为研究对象,利用数值模拟方法分析了端面... 详细信息

泄漏率和开启力是在研究非接触式机械密封性能需要考虑的2个重要指标.目前针对非接触式机械密封的结构优化研究,仅限于固定内径的密封环,优化结果缺乏通用性.以新型扩压式自泵送流体动压机械密封为研究对象,利用数值模拟方法分析了端面重要结构参数对其密封性能的交互影响;基于均匀试验设计和多元回归分析法建立了扩压式自泵送流体动压机械密封的开启力和泄漏率预测模型;采用NSGA2遗传算法进行双目标寻优,得到Pareto最优解集,再结合TOPSIS法从解集中筛选出了不同权重下的最优结构参数.研究结果表明:对于中小轴径的扩压式自泵送流体动压机械密封,动环端面密封坝坝长与扩压环槽槽宽的比值在1.46~2.01.间,螺旋槽槽长和扩压环槽槽宽的比值在1.32~1.86之间时,密封性能最优.研究成果为扩压式自泵送流体动压机械密封动环端面的设计提供理论基础.

关键词：非接触式机械密封数值模拟计算流体力学均匀试验设计优化 NSGA2遗传算法交互作用