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Modulation of Soil Particle Size and Nutrient Availability in the Maize Rhizosheath

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Pedosphere 2011年第4期21卷 483-490页

作者： MA Wei li Xue-xian li Chun-Jian Department of Plant Nutrition China Agricultural University Beijing 100193 (China)

Root exudates,microorganism colonization and soil aggregates together form the rhizosheath,a special cylinder of micro-ecosystem adhering to the root *** study how the rhizosheath affects soil structure and nutrient distribution,we analyzed the impact of maize rhizosheath on soil particle size and nutrient availability in pot and field *** results showed that there was a significant size decrease of soil particles in the ***,the soil mineral nitrogen in the rhizosheath was significantly higher than that in the rhizosphere or bulk soil at tasseling and maturity stages of *** contents of Fe and Mn were also differentially altered in the *** development,indicated by a dry weight ratio of rhizosheath soil to the root,was relatively independent of root development during the whole experimental *** formation of maize rhizosheath contributed to the modulation of soil particle size and nutrient *** subtle local changes of soil physical and chemical properties may have profound influence on soil formation,rhizospheric ecosystem initiation,and mineral nutrient mobilization over the long history of plant evolution and domestication.

关键词： micronutrient mineral nitrogen mucilage rhizosphere root exudates

A new lignan derivative from the root of Ilex pubescens

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Chinese Chemical Letters 2008年第5期19卷 550-552页

作者： Yu Bo Zhou Jin Hui Wang xiang Mei li xian li School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China

One new compound, ilexlignan A （1）, was isolated from the root of llex pubescens. Its structure was elucidated by the combination of one- and two-dimensional NMR analysis, mass spectrometry, CD spectrum measurement ... 详细信息

关键词： llex pubescens llexlignan A lignan

Deposition of crackless freestanding diamond films on Mo substrates with Zr interlayer

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 246-250页

作者： Zheng liu Cheng-ming li liang-xian Chen li-mei Wang li-fu Hei Fan-xiu Lu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The Mo substrate with Zr interlayer,namely composite substrate,was employed to solve the problem of crack formation in the freestanding diamond film *** diamond films deposited on the composite substrates by the direct current arc plasma jet chemical vapor deposition（CVD） method were investigated with scanning electron microscopy（SEM）,X-ray photoelectron spectroscopy （XPS）,X-ray diffraction（XRD）,and Raman *** addition,the stress distribution during the large area freestanding diamond film deposition on the composite substrate was analyzed based on the finite element model *** results reveal that Zr interlayer can be easily destroyed during the post-deposition cooling process,which is helpful for stress release and crack avoiding in diamond films.

关键词： chemical vapor deposition diamond film interlayer thermal stress finite element analysis

Perfect Optical Nonreciprocity with Mechanical Driving in a Three-Mode Optomechanical System

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Communications in Theoretical Physics 2019年第8期71卷 1011-1016页

作者： li-Hua Zhao xian-li li He-lin Lu Xue-Dong Tian College of Electronic Science Northeast Petroleum University Daqing 163318 China Department of Physics Yunnan Minzu University Kunming 650500 China College of Physics Science and Technology Guangxi Normal University Guilin 541004 China

Nonreciprocal devices are indispensable for building quantum networks and ubiquitous in modern communication ***, we study perfect optical nonreciprocity in a three-mode optomechanical system with mechanical *** scheme relies on the interference between optomechanical interaction and mechanical *** find perfect optical nonreciprocity can be achieved even though nonreciprocal phase difference is zero if we drive the system by a mechanical driving with a nonzero *** obtain the essential conditions for perfect optical nonreciprocity and analyze properties of the optical nonreciprocal *** results can be used to control optical transmission in quantum information processing.

关键词： cavity optomechanics optical nonreciprocity nonreciprocal transmission mechanical driving

Theoretical Design of Defects as a Driving Force for Ion Transport in li_(3)OBr Solid Electrolyte

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Energy & Environmental Materials 2024年第3期7卷 143-153页

作者： Xingyun Luo Yanlu li xian Zhao State Key Lab of Crystal Materials and Institute of Crystal Materials Shandong UniversityJinan 250100China Center for Optics Research and Engineering Shandong UniversityQingdao 266237China

Due to ever-increasing concerns about safety issues in using li ionic batteries,solid electrolytes have extensively *** li-rich antiperovskite li_(3)OBr has been considered as a promising solid electrolyte candidate,but it still suffers challenges to achieve a high ionic conductivity owing to the high intrinsic symmetry of the crystal ***,we presented a design strategy that introduces various point defects and grain boundaries to break the high lattice symmetry of li_(3)OBr crystal,and their effect and microscopic mechanism of promoting the migration of li-ion were explored *** has been found that li_(i)are the dominant defects responsible for the fast li-ion diffusion in bulk li_(3)OBr and its surface,but they are easily trapped by the grain boundaries,leading to the annihilating of the Frenkel defect pair V'_(li)+li_(i),and thus limits the V'_(li)diffusion at the grain *** V_(Br)defect near the grain boundaries can effectively drive V'_(li)across the grain boundary,thereby converting the carrier of li^(+)migration from li,in the bulk and surface to V'_(li)at the grain boundary,and thus improving the ionic conductivity in the whole li_(3)OBr *** work provides a comprehensive insight into the li^(+)transport and conduction mechanism in the li_(3)OBr *** opens a new way of improving the conductivity for all-solid-state li electrolyte material through the defect design.

关键词： defects density functional theory ionic migration solid electrolyte

One Dimensional Iron Molybdophosphate Anionic Chains with Different Structural Arrangements Reflecting a Flexibility Character

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Chemical Research in Chinese Universities 2013年第4期29卷 621-626页

作者： ZHOU Yun-shan HASSAN ul Sadaf li xian-qi ZHANG li-juan AHMAD Waqar SHI Zong-hai State Key Laboratory of Chemical Resource Engineering Institute of Science Beij'ing University of Chemical Technology Beijing 100029 P. R. China

Structural comparison of a new compound [（bpp）3H6]Fe2ⅢFe2ⅡMo24Ⅴ（H2PO4）8（HPO4）4（PO4）4O48（OH）12·（H2O）4·2H2O（1）[bpp=1,3-di（4-pyridyl）propane] with our previously reported two compounds [（bpy）3FeⅡ]3·Fe2ⅢFe2ⅡMo24Ⅴ（H2PO4）8（HPO4）4（PO4）4O48（OH）12（H2O）4·12H2O（2） and [（bpy）3FeⅡ]2FeⅡFeⅢMo12Ⅴ（H2PO4）2（H2-xPO4）.（H1＋xPO4）（HPO4）2（PO4）2O24（OH）6（H2O）2·9H2O（x=0-1）（3）（bpy=2,2＇-bipyridine）,which all exhibit one-dimensional mixed-valence iron molybdophosphate anionic chains constructed by alternating connection of FeⅢ ions and magic [FeⅡ（Mo6P4O31）2] units,reveals that the non-hydrogen atomic ratios of Mo∶Fe∶P∶O within the polymeric anionic chains are the same for all the three compounds,while the polymeric anionic chains of the different compounds bear different numbers of negative *** therefore there exist different numbers of counter cations per {Fe2Ⅲ[Fe2Ⅱ（P16Mo24ⅤO124）]} unit found in the titled *** discloses that not only are the spatial assembling of counter cations and polymeric inorganic chains of three compounds quite different,but also the O-FeⅢ-O bond angles and FeⅢ-O bond lengths of the three different inorganic chains exhibit small *** is more important is that such small changes in bond length and bond angle in the assemblage of FeⅢ-O bonds lead to the considerable fluctuations of inorganic chains in their structural conformation within the three compounds,reflecting an interesting phenomenon of＂flexibility＂ in the pure inorganic one dimensional mixed-valence iron molybdophosphate chains.

关键词： Flexibility Conformation Crystal structure Inorganic chain Iron molybdophosphate

Delving into high-quality SVBRDF acquisition: A new setup and method

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Computational Visual Media 2024年第3期10卷 523-541页

作者： Chuhua xian Jiaxin li Hao Wu Zisen lin Guiqing li School of Computer Science and Engineering South China University of TechnologyGuangzhou 510006China Guangdong Shidi Intelligence Technology Ltd.Guangzhou 510000China

In this study, we present a new andinnovative framework for acquiring high-qualitySVBRDF maps. Our approach addresses the limitations of the current methods and proposes a newsolution. The core of our method is a simple hardwaresetup consisting of a consumer-level camera, LEDlights, and a carefully designed network that canaccurately obtain the high-quality SVBRDF propertiesof a nearly planar object. By capturing a ﬂexiblenumber of images of an object, our network usesdifferent subnetworks to train different property mapsand employs appropriate loss functions for each ofthem. To further enhance the quality of the maps, weimproved the network structure by adding a novel skipconnection that connects the encoder and decoder withglobal features. Through extensive experimentation usingboth synthetic and real-world materials, our resultsdemonstrate that our method outperforms previousmethods and produces superior results. Furthermore,our proposed setup can also be used to acquire physicallybased rendering maps of special materials.

关键词： acquisition setup SVBRDF acquisition material capture global skip connection

Evaluation of transmission risk of respiratory particles under different ventilation strategies in an elevator

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Building Simulation 2024年第5期17卷 771-784页

作者： liangyu Zhu xian li Bujin Feng Fan liu School of Civil Engineering and Architecture Linyi UniversityLinyi276000China College of Agriculture Shandong Agricultural UniversityTaian271018China School of Environment and Architecture University of Shanghai for Science and TechnologyShanghai200093China

People in elevators are at risk of respiratory infection because the elevator cabin is crowded and has poor *** exhaled particles may be inhaled by the susceptible person,deposited on the surface and suspended in the elevator,which can result in direct and indirect ***,whether the air vent designs adopted in the elevator can effectively reduce the transmission risk of respiratory particles remains *** this study,the dispersion of particles under four common ventilation strategies used in the commercial elevator was investigated by proven computational fluid dynamics(CFD)*** flow field was simulated with the RNG κ-ξ turbulence model and the Lagrangian method was adopted to track particle *** effects of air vent layout and airflow rate on particle transmission were *** found that more than 50% of exhaled particles(average value)were suspended in the cabin and difficult to discharge under the investigated ventilation *** deposited fraction of particles on the susceptible person reached up to 39.14% for infiltration ventilation,which led to a high risk of contact *** the ventilation rate could not significantly reduce the inhalation proportion of particles due to the poor airflow distribution inside the elevator.A more proper ventilation strategy should be explored for the elevator to control transmission risk.

关键词： particle dispersion transmission risk elevator ventilation strategy computational fluid dynamics(CFD)

Multi-sensor multispectral reconstruction framework based on projection and reconstruction

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Science China(Information Sciences) 2024年第3期67卷 246-262页

作者： Tianshuai li Tianzhu liU xian li Yanfeng GU Yukun WANG Yushi CHEN School of Electronics and Information Engineering Harbin Institute of Technology Heilongjiang Province Key Laboratory of Space-Air-Ground Integrated Intelligent Remote Sensing

The scarcity and low spatial resolution of hyperspectral images(HSIs) have become a major problem limiting the application of the images. In recent years, spectral reconstruction(SR) has been applied to convert multispectral images(MSIs) with abundant quantities and high spatial resolution into HSIs. With the launch of several new multispectral(MS) satellites with a short repeat period, the simultaneous acquisition of images from multiple MS sensors in the same area is gradually becoming feasible. Unfortunately, existing SR methods only consider the reconstruction of the MSIs of a single sensor without considering using MSIs from different MS sensors to obtain a better construction effect through their complementary bands. However,multi-sensor SR is characterized by two problems: inconsistency in the amplitude information of real multisensor imaging and difficulty in the extraction of the complex correlations of bands from different *** solve these problems, this paper proposes a multi-sensor SR framework based on a two-step approach in which the problems of amplitude inconsistency and band information extraction are solved using an ideal projection network and an ideal multi-sensor SR network, respectively. The effectiveness of the proposed method is verified by experiments on three datasets.

关键词： spectral reconstruction spectral superresolution hyperspectral image multispectral image neural networks multi-sensor