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Regulation of the water status in three co-occurring phreatophytes at the southern fringe of the Taklamakan Desert

Journal of Plant Ecology 2008年第4期1卷 227-235页

作者： frank M.Thomas Andrea Foetzki Dirk Gries Helge Bruelheide Xiangyi li Fanjiang Zeng Ximing Zhang Department of Plant Ecology Albrecht von Haller Institute for Plant SciencesGeorg-August-Universitat GottingenUntere Karspule 237073 GottingenGermany Present address:Department of Geobotany University of TrierBehringstraße 2154296 TrierGermany Eidgenossisches Institut fur Agrarokologie und Landwirtschaft Forschungsanstalt AgroscopeReckenholzstrasse 1918046 ZurichSwitzerland Institute of Geobotany and Botanical Garden Martin Luther University Halle-WittenbergAm Kirchtor 106108 Halle(Saale)Germany Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences40 South Beijing Road830011 UrumqiChina

Aims We investigated the regulation of the water status in three predominant perennial C3 phreatophytes(Alhagi sparsifolia,Populus euphratica,Tamarix ramosissima)at typical sites of their occurrence at the southern fringe of the hyperarid Taklamakan Desert(north-west China).Methods In the foreland of the river oasis of Qira(Cele),we determined meteorological variables,plant biomass production,plant water potentials(WL)and the water flux through the *** calculated the hydraulic conductance on the flow path from the soil to the leaves(kSL)and tested the effects of kSL,WL and the leaf-to-air difference in the partial pressure of water vapour(Dw)on stomatal regulation using regression *** Findings Despite high values of plant water potential at the point of turgor loss,all plants sustained WL at levels that were high enough to maintain transpiration throughout the growing *** ***,stomatal resistance(rs;related to leaf area or leaf mass)was most closely correlated with kSL;whereas in ***,~70%of the variation in rs was explained by *** ***,leaf area-related rs was significantly correlated with WL and *** regulation mechanisms are in accordance with the growth patterns and the occurrence of the species in relation to their distance to the ground water.

关键词： aboveground growth extreme aridity stomatal conductance transpirational demand vapour pressure deficit

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Construction Activity Analysis of Workers Based on Human Posture Estimation Information

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Engineering 2024年第2期33卷 225-236页

作者： Xuhong Zhou Shuai li Jiepeng liu Zhou Wu Yohchia frank Chen School of Civil Engineering Chongqing UniversityChongqing 400044China School of Automation Chongqing UniversityChongqing 400044China Department of Civil Engineering The Pennsylvania State UniversityMiddletownPA 17057USA

Identifying workers’construction activities or behaviors can enable managers to better monitor labor efficiency and construction ***,current activity analysis methods for construction workers rely solely on manual observations and recordings,which consumes considerable time and has high labor *** have focused on monitoring on-site construction activities of ***,when multiple workers are working together,current research cannot accu rately and automatically identify the construction *** research proposes a deep learning framework for the automated analysis of the construction activities of multiple *** this framework,multiple deep neural network models are designed and used to complete worker key point extraction,worker tracking,and worker construction activity *** designed framework was tested at an actual construction site,and activity recognition for multiple workers was performed,indicating the feasibility of the framework for the automated monitoring of work efficiency.

关键词： Pose estimation Activity analysis Object tracking Construction workers Automatic systems

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Novel hierarchical structure of MoS_(2)/TiO_(2)/Ti_(3)C_(2)T_(x) composites for dramatically enhanced electromagnetic absorbing properties

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Journal of Advanced Ceramics 2021年第5期10卷 1042-1051页

作者： Heng DU Qipeng ZHANG Biao ZHAO frank MARKEN Qiancheng GAO Hongxia LU li GUAN Hailong WANG Gang SHAO Hongliang XU Rui ZHANG Bingbing FAN School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China hKey Laboratory of Functional Molecular Solids Ministry of EducationAnhui Normal UniversityWuhu 241000China Henan Key L abomtory of Aeronautical Materials and Application Technology Zhengzhou University of AeronauticsZhengzhou 450046China Department of Chemistry University of BathClaverton DownBath BA27AYUK School of Materials Science and Engineering L uoyang Institute of Science and TechnologyLuoyang 471023China

In order to prevent the microwave leakage and mutual interference,more and more microwave absorbing devices are added into the design of electronic products to ensure its routine *** this work,we have successfully prepared MoS_(2)/TiO_(2)/Ti_(3)C_(2)T_(x) hierarchical composites by one-pot hydrothermal method and focused on the relationship between structures and electromagnetic absorbing *** by comprehensive characterizations,M0S_(2) nanosheets were proved to be anchored on the surface and interlayer of Ti_(3)C_(2)T_(x) through a hydrothermal ***,TiO_(2) nanoparticles were obtained in *** to these hierarchical structures,the MoS_(2)/TiO_(2)/Ti_(3)C_(2)T_(x) composites showed greatly enhanced microwave absorbing *** MoS_(2)/TiO_(2)/Ti_(3)C_(2)T_(x) composites exhibit a maximum reflection loss value of -33.5 dB at 10.24 GHz and the effective absorption bandwidth covers 3.1GHz(13.9-17 GHz)at the thickness of 1.0 mm,implying the features of wide frequency and light *** work in the hierarchical structure of MoS_(2)/TiO_(2)/Ti_(3)C_(2)T_(x) composites opens a promising door to the exploration of constructing extraordinary electromagnetic wave absorbents.

关键词： MoS_(2)/TiO_(2)/Ti_(3)C_(2)T_(x)hierarchical hybrids microwave absorbing properties dielectric loss

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Electronic structure factors and the importance of adsorbate effects in chemisorption on surface alloys

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npj Computational Materials 2022年第1期8卷 1560-1571页

作者： Shikha Saini Joakim Halldin Stenlid frank Abild-Pedersen SUNCAT Center for Interface Science and Catalysis Department of Chemical EngineeringStanford University443 Via OrtegaStanfordCA94305USA SUNCAT Center for Interface Science and Catalysis SLAC National Accelerator Laboratory2575 Sand Hill RoadMenlo ParkCA94025USA

The chemisorption energy is an integral aspect of surface chemistry,central to numerous fields such as catalysis,corrosion,and ***-structure-based methods such as the Newns-Anderson model are therefore of great importance in guiding the engineering of material surfaces with optimal ***,existing methods are inadequate for interpreting complex,multi-metallic ***,we introduce a physics-based chemisorption model for alloyed transition metal surfaces employing primarily metal d-band properties that accounts for perturbations in both the substrate and adsorbate electronic states upon ***,we show that adsorbate-induced changes in the adsorption site interact with its chemical environment leading to a second-order response in chemisorption energy with the d-filling of the neighboring *** demonstrate the robustness of the model on a wide range of transition metal alloys with O,N,CH,and li adsorbates yielding a mean absolute error of 0.13 eV versus density functional theory reference chemisorption energies.

关键词： alloys corrosion chemisorption

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A comprehensive review on proppant technologies

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Petroleum 2016年第1期2卷 26-39页

作者： Feng liang Mohammed Sayed Ghaithan A.Al-Muntasheri frank F.Chang Leiming li Aramco Services Company Aramco Research Center-Houston16300 Park RowHoustonTX 77084USA Saudi Aramco P.O.Box 5614Dhahran31311Saudi Arabia

The main function of traditional proppants is to provide and maintain conductive fractures during well production where proppants should meet closure stress requirement and show resistance to diagenesis under downhole *** different proppants have been developed in the oil&gas industry,with various types,sizes,shapes,and *** most proppants are simply made of silica or ceramics,advanced proppants like ultra-lightweight proppant is also desirable since it reduces proppant settling and requires low viscosity fluids to ***,multifunctional proppants may be used as a crude way to detect hydraulic fracture geometry or as matrices to slowly release downhole chemical additives,besides their basic function of maintaining conductive hydraulic *** from the conventional approach where proppant is pumped downhole in frac fluids,a revolutionary way to generate in-situ spherical proppants has been reported *** paper presents a comprehensive review of over 100 papers published in the past several decades on the *** objectives of this review study are to provide an overview of current proppant technologies,including different types,compositions,and shapes of proppants,new technologies to pump and organize proppants downhole such as channel fracturing,and also in-situ proppant ***,the paper sheds light on the current challenges and emphasizes needs for new proppant development for unconventional resources.

关键词： Proppant lightweight Multifunctional proppant Channel fracturing In-situ proppant generation

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Perovskite Solar Cells toward Eco-Friendly Printing

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Research 2021年第1期2021卷 586-596页

作者： Xiaoming Chang Yuanyuan Fan Kui Zhao Junjie Fang Dongle liu Ming-Chun Tang Dounya Barrit Detlef-MSmilgies Ruipeng li Jing Lu Jianbo li Tinghuan Yang Aram Amassian Zicheng Ding Yonghua Chen Shengzhong(frank)liu Wei Huang Key Laboratory of Applied Surface and Colloid Chemistry Ministry of EducationShaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710119China King Abdullah University of Science and Technology(KAUST) KAUST Solar Center(KSC)and Physical Science and Engineering Division(PSE)Thuwal 23955-6900Saudi Arabia Cornell High Energy Synchrotron Source Cornell UniversityIthacaNY 14850USA NSLS II Brookhaven National LabUpton New York 11973USA Department of Materials Science and Engineering and Carbon and Organic Electronics Laboratories(ORaCEL)North Carolina State UniversityRaleighNC 27695USA Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Nanjing Tech University(NanjingTech)Nanjing211800 JiangsuChina Dalian National Laboratory for Clean Energy iChEMDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Frontiers Science Center for Flexible Electronics Shaanxi Institute of Flexible Electronics(SIFE)and Xi’an Institute of Biomedical Materials&EngineeringNorthwestern Polytechnical University(NPU)127 West Youyi RoadXi’an710072 ShaanxiChina

Eco-friendly printing is important for mass manufacturing of thin-film photovoltaic(PV)devices to preserve human safety and the environment and to reduce energy consumption and capital ***,it is challenging for perovskite PVs due to the lack of eco-friendly solvents for ambient fast *** this study,we demonstrate for the first time an eco-friendly printing concept for high-performance perovskite solar *** the perovskite and charge transport layers were fabricated from eco-friendly solvents via scalable fast blade coating under ambient *** perovskite dynamic crystallization during blade coating investigated using in situ grazing incidence wide-angle X-ray scattering(GIWAXS)reveals a long sol-gel window prior to phase transformation and a strong interaction between the precursors and the eco-friendly *** insights enable the achievement of high quality coatings for both the perovskite and charge transport layers by controlling film formation during scalable *** excellent optoelectronic properties of these coatings translate to a power conversion efficiency of 18.26%for eco-friendly printed solar cells,which is on par with the conventional devices fabricated via spin coating from toxic solvents under inert *** eco-friendly printing paradigm presented in this work paves the way for future green and highthroughput fabrication on an industrial scale for perovskite PVs.

关键词： coating printing blade

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中国西部地区植被净初级生产力的时空格局

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生态学报 2005年第5期25卷 1026-1032,i005页

作者：卢玲李新 frank Veroustraete 中国科学院寒区旱区环境与工程研究所兰州730000 比利时佛莱芒区科技研究所遥感与大气过程中心

利用基于Monteith光能利用率理论的碳通量估算模型C- FIX,1km分辨率逐旬SPOT/ VEGETATION遥感数据和全球1.5°×1.5°格网化逐日气象数据,估算了2 0 0 2年中国西部地区植被净初级生产力(NPP)。对西部地区植被NPP的空间分布格局、季节变... 详细信息

利用基于Monteith光能利用率理论的碳通量估算模型C- FIX,1km分辨率逐旬SPOT/ VEGETATION遥感数据和全球1.5°×1.5°格网化逐日气象数据,估算了2 0 0 2年中国西部地区植被净初级生产力(NPP)。对西部地区植被NPP的空间分布格局、季节变化及不同土地利用类型植被的NPP总量和平均生产力水平进行了初步研究。结果表明:2 0 0 2年我国西部地区植被年NPP总量约为0 .96 Pg C(1Pg=10 1 5g)。西部地区年NPP空间分布基本格局是东南和西北两区域高,然后以东南西北方向为轴心逐渐向内陆中心迅速递减,该分布格局与各区域的水热条件差异和植被类型的地带性分异规律紧密相关。西部地区陆地生态系统NPP具有显著的季相变化规律,这与温度、降水的季节变化以及人为生产活动安排有很高的相关性。西部地区尽管土地面积广阔,由于区域气候和自然条件相对恶劣,导致土地资源可利用率差,生态系统整体生产力水平相对低下,区域内各种土地利用类型植被的生产力水平差异大且空间分布十分不均衡,是我国生态环境相对脆弱的区域。

关键词：净初级生产力 C—FIX模型遥感中国西部地区

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Reduced EGFR signaling enhances cartilage destruction in a mouse osteoarthritis model

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Bone Research 2014年第3期2卷 182-193页

作者： Xianrong Zhang Ji Zhu Fei liu Yumei li Abhishek Chandra L Scott Levin frank Beier Motomi Enomoto-Iwamoto ling Qin Department of Orthopaedic Surgery School of Medicine University of Pennsylvania Philadelphia PA USA Department of Physiology School of Basic Medical Sciences Wuhan University Department of Plastic and Reconstructive Surgery Shanghai Ninth People’s Hospital Shanghai Municipal Hospital of Traditional Chinese Medicine Shanghai University of Traditional Chinese Medicine Department of Physiology and Pharmacology Schulich School of Medicine and Dentistry University of Western Ontario London ONCanada Department of Surgery The Children’s Hospital of Philadelphia

Osteoarthritis （OA） is a degenerative joint disease and a major cause of pain and disability in older adults. We have previously identified epidermal growth factor receptor （EGFR） signaling as an important regulator of cartilage matrix degradation during epiphyseal cartilage development. To study its function in OA progression, we performed surgical destabilization of the medial meniscus （DMM） to induce OA in two mouse models with reduced EGFR activity, one with genetic modification （, was/＋ mice） and the other one with pharmacological inhibition （gefitinib treatment）. Histological analyses and scoring at 3 months post-surgery revealed increased cartilage destruction and accelerated OA progression in both mouse models. TUNEL staining demonstrated that EGFR signaling protects chondrocytes from OA-induced apoptosis, which was further confirmed in primary chondrocyte culture. Immunohistochemistry showed increased aggrecan degradation in these mouse models, which coincides with elevated amounts of ADAMTS5 and matrix metalloproteinase 13 （MMP13）, the principle proteinases responsible for aggrecan degradation, in the articular cartilage after DMM surgery. Furthermore, hypoxia-inducible factor 2α （HIF2α）, a critical catabolic transcription factor stimulating MMP13 expression during OA, was also upregulated in mice with reduced EGFR signaling. Taken together, our findings demonstrate a primarily protective role of EGFR during OA progression by regulating chondrocyte survival and cartilage degradation.

关键词： EGFR Reduced EGFR signaling enhances cartilage destruction in a mouse osteoarthritis model

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季节性放牧改变大针茅养分回收和根系养分储存并影响其翌年春季返青生长

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Journal of Plant Ecology 2023年第2期16卷 189-203页

作者： Tongrui Zhang frank Yonghong li lin Wu Hao Wang Yanlong li Chunjun Shi Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau&Inner Mongolia Key Laboratory of Grassland Ecology School of Ecology and EnvironmentInner Mongolia UniversityHohhot 010021China Joint Innovation Center for Grassland Ecological Security of the Ministry of Education of China Inner Mongolia UniversityHohhot 010031China Institute of Grassland Research Chinese Academy of Agricultural SciencesHohhot 010010China

秋季养分回收是草地多年生植物保存和高效利用养分的关键机制。放牧对植物养分回收的影响可能改变根系养分储存,进一步影响植物在翌年春季的返青生长。多数研究关注于放牧草地植物养分回收和保存,而其对植物在翌年春季返青生长的影响研... 详细信息

秋季养分回收是草地多年生植物保存和高效利用养分的关键机制。放牧对植物养分回收的影响可能改变根系养分储存,进一步影响植物在翌年春季的返青生长。多数研究关注于放牧草地植物养分回收和保存,而其对植物在翌年春季返青生长的影响研究则较少。本研究以半干旱草原多年生优势禾草——大针茅(Stipa grandis)为模式植物,具体评估了4种季节性放牧管理下(不放牧、春季放牧、夏季放牧和秋季放牧)大针茅植株水平的养分回收特征(养分回收度、回收效率和回收通量)、根系养分动态,以及翌年植物返青状况,旨在探究植物养分回收、根系养分储存和翌年返青生长对不同季节放牧的响应。研究结果显示,(i)大针茅氮回收效率为51%–66%、磷回收效率为58%–80%,养分回收通量在秋季放牧下最低,在春季放牧下最高。(ii)大针茅根系养分储存特征在夏季放牧下显著降低,在春季放牧下轻微下降,而在秋季放牧下则无变化。(iii)翌年春季大针茅返青生长状况在早春放牧下最佳,在秋季放牧下最差,这一现象主要受土壤水分的影响,而与根系养分储存无关。本研究为深入了解植物养分循环过程,建立草原保护和合理放牧管理制度提供了理论依据。

关键词：大针茅(Stipa grandis) 季节性放牧养分回收养分保存土壤水分

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In-situ photoisomerization of azobenzene to inhibit ion-migration for stable high-efficiency perovskite solar cells

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Journal of Energy Chemistry 2022年第10期31卷 556-564,I0014页

作者： Xuejiao Zuo Yiyang He Hongyu Ji Yong li Xiuying Yang Binxun Yu Tao Wang Zhike liu Wenliang Huang Jing Gou Ningyi Yuan Jianning Ding Shengzhong frank liu Shaanxi Key Laboratory for Advanced Energy Devices Shaanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi’an 710119ShaanxiChina School of Chemistry and Chemical Engineering Shaanxi Normal UniversityXi’an 710119ShaanxiChina School of Materials Science and Engineering Jiangsu Collaborative Innovation Center of Photovoltaic Science and EngineeringJiangsu Province Cultivation Base for StateKey Laboratory of Photovoltaic Science and TechnologyChangzhou UniversityChangzhou 213164JiangsuChina

Ion migration is a notorious problem in perovskite solar cells(PSCs)that severely mutilates device ***,a strategy to inhibit ion migration in situ is developed by using photoisomerization of azobenzene(AZO)to immobilize cations in the *** the nucleation process,the photoisomerized cis-AZO reacts with FA^(+),MA^(+)and Pb2+cations in the perovskite precursor by synergistic cation-πinteraction and Lewis base coordination,leading to heterogeneous nucleation to produce uniform perovskite ***,it accelerates conversion of intermediate yellowδ-phase to desired black aphase of FAPb I3for improved crystallinity with well-passivated grain ***,defect density is effectively reduced for the perovskite film to demonstrate suppressed carrier recombination and enhanced carrier ***,the solar cell efficiency is elevated from 21.29%to 23.58%with negligible J-V ***-term stability is also improved,with the bare device without any encapsulation retaining 84%of its initial efficiency after aging 744 hours in ambient.

关键词： Perovskite Solar cell Photovoltaic Photoisomerization

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