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Advances in Atmospheric Sciences 2009年第5期26卷 887-894页

作者：高志球 Qing WANG 周明煜 state key laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 Department of Meteorology Naval Postgraduate School Monterey California USA key laboratory for Polar Science Polar Research Institute of China Shanghai 200136

The parameterization of friction velocity, roughness length, and the drag coefficient over coastal zones and open water surfaces enables us to better understand the physical processes of air-water interaction. In context of measurements from the Humidity Exchange over the Sea Main Experiment （HEXMAX）, we recently proposed wave-parameter dependent approaches to sea surface friction velocity and the aerodynamic roughness by using the dimensional analysis method. To extend the application of these approaches to a range of natural surface conditions, the present study is to assess this approach by using both coastal shallow （RASEX） and open water surface measurements （Lake Ontario and Grand Banks ERS-1 SAR） where wind speeds were greater than 6.44 m s-1. Friction velocities, the surface aerodynamic roughness, and the neutral drag coefficient estimated by these approaches under moderate wind conditions were compared with the measurements mentioned above. Results showed that the coefficients in these approaches for coastal shallow water surface differ from those for open water surfaces, and that the aerodynamic roughness length in terms of wave age or significant wave height should be treated differently for coastal shallow and open water surfaces.

关键词： sea surface roughness wave parameter friction velocity parameterization

Regeneration pattern analysis of Quercus liaotungensis in a temperate forest using two-dimensional wavelet analysis

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Frontiers in Biology 2009年第4期4卷 491-502页

作者： Xiangcheng MI Jihua HOU state key laboratory of Vegetation and Environmental Change Institute of Botanythe Chinese Academy of SciencesBeijing 100093China key laboratory for Silviculture and Conservation the Ministry of EducationBeijing Forestry UniversityBeijing 100083China

This paper introduces the two-dimensional(2D)wavelet analysis as a general interrogative technique for the detection of spatial structure in lattice *** 2D wavelet analysis detects components of hierarchical structure and displays the locational information of the *** and gaps of different spatial scales in graphical presentation of wavelet coefficients can be linked to the local ecological processes that determine patterns at stand or landscape *** from the 2D wavelet transform function,the calculation of wavelet variance can reduce the four-dimensional data of wavelet coefficients to a two-dimensional wavelet variance function and quantify the contribution of the given scale to the overall *** illustrate the use of the 2D wavelet analysis by analyzing two simulated patterns and identifying the regeneration pattern of the Quercus liaotungensis in a warm temperate forest in north *** results indicate that the recruitment of *** occurs in an overlapping area between the patch of adult and canopy gap at scales of 45m×45m–70m×70m and 20m×20m–30m×*** regeneration pattern of *** can be mainly ascribed to a trade-off between two ecological processes:recruitment around parent trees and the physiological light requirements of seedlings and *** results provide a general portrayal of the regeneration pattern for the dispersal-limited and shade-intolerant Quercus *** find that the two-dimensional wavelet analysis efficiently characterizes the scale-specific pattern of *** at different life-history stages.

关键词： Halo wavelet pattern analysis Quercus liaotungensis regeneration scale two-dimensional Mex-ican Hat wavelet two-dimensional wavelet analysis wavelet variance

Relationship between soil surface roughness and hydraulic roughness coefficient on sloping farmland

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Water Science and Engineering 2012年第2期5卷 191-201页

作者： Zi-cheng ZHEN Shu-qin HE Fa-qi WU College of Resources and Environment Sichuan Agricultural University Chengdu 611130 P. R. China state key laboratory of Earth Surface processes and Resource Ecology Beijing Normal University Beijing 100875 P. R. China state key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Water and Soil Conservation Chinese Academy of Sciences and Ministry of Water Resources Yangling 712100 P. R. China College of Resources and Environment Northwest A &F University Yangling 712100 P. R. China

The soil surface roughness and hydraulic roughness coefficient are important hydraulic resistance characteristic parameters. Precisely estimating the hydraulic roughness coefficient is important to understanding mechanisms of overland flow. Four tillage practices, including cropland raking, artificial hoeing, artificial digging, and straight slopes, were considered based on the local agricultural conditions to simulate different values of soil surface roughness in the Loess Plateau. The objective of this study was to investigate the relationship between the soil surface roughness and hydraulic roughness coefficient on sloping farmland using artificial rainfall simulation. On a slope with a gradient of 10°, a significant logarithmic function was developed between the soil surface roughness and Manning＇s roughness coefficient, and an exponential function was derived to describe the relationship between the soil surface roughness and Reynolds number. On the slope with a gradient of 15°, a significant power function was developed to reflect the relationship between the soil surface roughness and Manning＇s roughness coefficient, and a linear function was derived to relate the soil surface roughness to the Reynolds number. These findings can provide alternative ways to estimate the hydraulic roughness coefficient for different types of soil surface roughness.

关键词： soil hydraulics sloping farmland," soil erosion soil surface roughness hydraulic roughness coefficient Reynolds number tillage practice

Selective electrocatalytic reduction of CO_(2) to formate via carbon-shell-encapsulated In_(2)O_(3) nanoparticles/graphene nanohybrids

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Journal of Materials Science & Technology 2022年第26期121卷 220-226页

作者： Yidu Wang Jingnan Ding Jun Zhao Jiajun Wang Xiaopeng Han Yida Deng Wenbin Hu key laboratory of Advanced Ceramics and Machining Technology(Ministry of Education) Tianjin Key Laboratory of Composite and Functional MaterialsSchool of Materials Science and EngineeringTianjin UniversityTianjin 300072China state key laboratory of Marine Resource Utilization in South China Sea School of Materials Science and EngineeringHainan UniversityHaikou 570228China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhouBinhai New City 350207China

Constructing nanohybrids with a synergistic effect using multi-components and specific micro/nanostructures can significantly enhance their electrocatalytic *** this work,we fabricated an In_(2)O_(3)■NC@GO nanohybrid,in which In_(2)O_(3)nanoparticles(NPs)were encapsulated by an N-doped carbon(NC)shell and supported on *** multi-components in In_(2)O_(3)■NC@GO synergistically optimize the structural and electronic properties of the *** particle size and dispersion of In_(2)O_(3)NPs were optimized owing to the separation effect of the amorphous NC shell and graphene *** separation effect exposes more number of active sites for the electrochemical *** oxygen vacancies exist in In_(2)O_(3),leading to a stronger ability for the adsorption and activation of *** NC shell inhibits the direct contact between the electrolyte and In_(2)O_(3),which significantly suppresses competitive *** charge transfer during the electrocatalysis process is also effectively enhanced due to the carbon *** synergistic effect of multi-components in the In_(2)O_(3)■NC@GO sample results in a significantly improved COreduction reaction performance with a high HCOOFaradic efficiency(FE)of 91.2%and a current density of 40.38 m A cmat–0.8 V obtained using a flow *** present work demonstrates that rationally designing nanohybrids with multifunctional components is an effective strategy for optimizing the structural and electrocatalytic properties of materials for energy conversion.

关键词： In_(2)O_(3) CO_(2)reduction electrocatalyst Oxygen vacancies N-doped carbon Nanohybrids

Revegetation with artificial plants improves topsoil hydrological properties but intensifies deep-soil drying in northern Loess Plateau,China

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Journal of Arid Land 2018年第3期10卷 335-346页

作者： ZHANG Qingyin JIA Xiaoxu ZHAO Chunlei SHAO Ming'an state key laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F University key laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences

Knowledge about the effects of vegetation types on soil properties and on water dynamics in the soil profile is critical for revegetation strategies in water-scarce regions, especially the choice of vegetation type and human management measures. We focused on the analysis of the effects of vegetation type on soil hydrological properties and soil moisture variation in the 0–400 cm soil layer based on a long-term（2004―2016） experimental data in the northern Loess Plateau region, China. Soil bulk density（BD）, saturated soil hydraulic conductivity（Ks）, field capacity（FC） and soil organic carbon（SOC） in 2016, as well as the volumetric soil moisture content during 2004–2016, were measured in four vegetation types, i.e., shrubland（korshinsk peashrub）, artificial grassland（alfalfa）, fallow land and cropland（millet or potato）. Compared with cropland, revegetation with peashrub and alfalfa significantly decreased BD and increased Ks, FC, and SOC in the 0–40 cm soil layer, and fallow land significantly increased FC and SOC in the 0–10 cm soil layer. Soil water storage（SWS） significantly declined in shrubland and grassland in the 40–400 cm soil layer, causing severe soil drought in the deep soil layers. The study suggested that converting cropland to grassland（alfalfa） and shrubland（peashrub） improved soil-hydrological properties, but worsened water conditions in the deep soil profile. However, natural restoration did not intensify deep-soil drying. The results imply that natural restoration could be better than revegetation with peashrub and alfalfa in terms of good soil hydrological processes in the semi-arid Loess Plateau region.

关键词： soil drying soil hydrological property soil moisture vegetation restoration Loess Plateau

Polymer Solar Cells with Improved Power Conversion Efficiency Using Solvent Mixtures

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Chemical Research in Chinese Universities 2017年第3期33卷 466-470页

作者： ZHANG Chunxia XU Xu ZHANG Panpan DANG Yang KANG Bonan state key laboratory on Integrated Optoelectronics College of Electronic Science and Engineering Jilin University Changchun 130012 P. R. China

In this paper, the effects of solvent mixtures on the morphology, charge transport, and light trapping of poly[N-900-hepta-decanyl-2,7-carbazole-alt-5,5-（40,70-di-2-thienyl-20,10,30-benzothiadiazole）]（PCDTBT） and [6,6]-phenyl C71-butyric acid methyl ester（PC71BM） based solar cells were investigated. As a good solvent for PCDTBT, o-dichlorobenzene（ODCB） was selected to mix with chloroform（CF）, chlorobenzene（eB）, and 1,2,4-Trichloroben-zene（TCB） for optimizing the morphology of the PCDTBT：PCTIBM active layer. It can be found that the device performance of polymer solar cells（PSCs） has been greatly improved when using a optimal blend ratio. Especially, the PSCs fabricated via ODCB（90%）/CF（10%, volume fraction） mixture exhibit a remarkable enhancement of photon-to-current efficiency（PCE） from 5.16% to 7.47%. The enhanced performance of the PSCs can be attributed to the higher absorption, the lower resistance, and the optimized surface morphology of the active layers modified by the solvent mixtures.

关键词： Solvent mixture Phase separation Electron transport Morphology Polymer solar cell

A Novel Zirconium-Based Perovskite-Type membrane Material for Oxygen Permeation

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Chinese Chemical Letters 2001年第9期12卷 835-838页

作者： Jian Hua TONG Wei Shen YANG Rui CAI Bai Chun ZHU state key laboratory of Catalysis Dalian Institute of Chemical Physics Chinese Academy of SciencesP.O.Box 110Dalian 116023

A novel zirconium-based membrane material of BaCo0.4Fe0.4Zr0.2O3-6 with cubic perovskite structure was synthesized for the first time through a method of citric and EDTA acid combined complexes. The structural stability was characterized by XRD, O-2-TPD and H-2-TPR techniques respectively. The high oxygen permeation flux of 0.873 mL/cm(2) min at 950 degreesC was obtained under He/Air gradient. Meanwhile, the single activation energy for oxygen permeation and the long-term steady operation of 200 h at 800 degreesC were achieved.

关键词： Perovskite mixed-conducting oxygen separation zirconium

Reversible fluorescent probes for chemical and biological redox process

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Chinese Chemical Letters 2017年第10期28卷 1929-1934页

作者： Biao Li Zhaoshuai He Hanxin Zhou Han Zhang Tanyu Cheng key laboratory of Resource Chemistry of Ministry of Education Key Laboratory of Rare Earth Functional Materials Department of Chemistry Shanghai Normal University Shanghai 200234 China

Oxidation and reduction are important chemical and biological processes. The redox state is related with physical functions and health. Thus, it is meaningful to develop tools for study the redox *** is a powerful method to connecting the microcosm and macrocosm. In this review, we discuss the recent progress of reversible fluorescent probes for chemical and biological redox process according to different active centers.

关键词： Redox probe Fluorescent probe Reversible probe Reactive oxygen and nitrogen species Quinone

Linking vegetation cover patterns to hydrological responses using two process-based pattern indices at the plot scale

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Science China Earth Sciences 2013年第11期56卷 1888-1898页

作者： LIU Yu FU BoJie Lü YiHe GAO GuangYao WANG Shuai ZHOU Ji state key laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of Sciences laboratory of Digital Earth Sciences Institute of Remote Sensing and Digital EarthChinese Academy of Sciences

Vegetation cover pattern is one of the factors controlling hydrological processes. Spatially distributed models are the primary tools previously applied to document the effect of vegetation cover patterns on runoff and soil erosion. Models provide precise estimations of runoff and sediment yields for a given vegetation cover pattern. However, difficulties in parameterization and the problematic explanation of the causes of runoff and sedimentation rates variation weaken prediction capability of these models. Landscape pattern analysis employing pattern indices based on runoff and soil erosion mechanism provides new tools for finding a solution. In this study, the vegetation cover pattern was linked with runoff and soil erosion by two previously de- veloped pattern indices, which were modified in this study, the Directional Leakiness Index （DL[） and Flowlength. Although they use different formats, both indices involve connectivity of sources ,areas （interpatch bare areas）. The indices were revised by bringing in the functional heterogeneity of the plant cover types and the landscape position. Using both artificial and field verified vegetation cover maps, observed runoff and sediment production on experiment plots, we tested the indices＇ efficiency and compared the indices with their antecedents. The results illustrate that the modified indices are more effective in indicating runoff at the plot/hillslope scale than their antecedents. However, sediment export levels are not provided by the modified indices. This can be attributed to multi-factor interaction on the hydrological process, the feedback mechanism between the hydrological function of cover patterns and threshold phenomena in hydrological processes.

关键词： cover pattern indices runoff soil erosion vegetation cover pattern

Atomic layer deposition for advanced nanomanufacturing

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Science China(Technological Sciences) 2022年第9期65卷 2218-2220页

作者： CAO Kun LIU Xiao YANG Fan CHEN Rong state key laboratory of Digital of Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Moore’s law drives the semiconductor industry to continuously shrink the critical size of transistors, however, the current fabrication processes still have challenges in future downscaling. It is a trade-off to improve the controllability for atomic-scale manufacturing with high accuracy and efficiency. Besides further downscaling, flexible electronics including flexible processors, displays.

关键词： layer shrink continuously