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Visible characteristics of space-based targets based on bidirectional reflection distribution function

Science China(Technological Sciences) 2012年第4期55卷 982-989页

作者： wang HongYuan ZHANG Wei wang fugang Research Center for Space Optical Engineering Harbin Institute of TechnologyHarbin 150001China

A precise modeling method of visible characteristics of the space-based target was presented based on bidirectional reflection distribution function (BRDF). The background characteristics of the space-based target were represented to build models of direct solar radiation and reflected radiation of the Earth based on blackbody radiation theory. The geometry characteristics of the target were analyzed to establish a surface equation of each surface based on its body coordinate system. The material characteristics of the target surface were described by introducing a BRDF model which considers the character of surface Gauss statistics and self-shadow and is obtained by measurement and modeling in advance. The relative positions of the space-based target, the background radiation sources and the observation platform were determined based on coordinate con- version to judge contributing surface of the target to observation system. Then a mathematical model on visible characteristics of the space target for the given optical system was built by summing reflection components of all the surfaces. Simulation of visible characteristics of the space-based target in orbit was achieved according to its given geometrical dimensions, physical parameters and orbital parameters. The results show that the method is effective for analysis on visible characteristics of the space-based target when single reflection is considered and its surface is regularly described in a surface equation, which provides a way to real-time calculation of visible characteristics of the space-based target.

关键词： space optics space-based target visible characteristics bidirectional reflection distribution function (BRDF)

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Simulation of Cefoselis hydrochloride adsorption on macroporous resin in a fixed-bed column using orthogonal collocation

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Chinese Journal of Chemical Engineering 2018年第9期26卷 1822-1828页

作者： Feng Xue fugang wang Shuai Chen Sheng wang Shengui Ju Weihong Xing College of Chemical Engineering Nanjing Tech University

Adsorption operation is of great importance for separation and purification of semi-synthetic cephalosporin compounds in pharmaceutical industry. The adsorption dynamics of Cefoselis hydrochloride(CFH) on XR 920 C adsorbent in fixed bed was predicted by the model of modified film-pore diffusion(MFPD). The intraparticle diffusion equation and mass balance equation in fixed bed are discretized into two ordinary differential equations(ODEs) using the method of orthogonal collocation which largely improves the calculation accuracy. The MFPD model parameters including the pore diffusion coefficient(Dp), external mass-transfer coefficient(kf), and the axial dispersion(DL) were estimated. The kfvalue was calculated by the Carberry equation, in which the effective diffusion coefficient Dewas fitted based on Crank Model through experimental data. Moreover, three key operating parameters(i.e., initial adsorbate concentration; flow rate of import feed, and bed height of adsorbent) and the corresponded breakthrough curves were systematically studied and optimized. Therefore,this research not only provides valuable experimental data, but also a successfully mathematical model for designing the continuous chromatographic adsorption process of CFH.

关键词： Cefoselis hydrochloride Breakthrough curve Orthogonal collocation Macroporous resin Fixed bed Simulation

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An effective planting model to decrease cadmium accumulation in rice grains and plants:Intercropping rice with wetland plants

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Pedosphere 2023年第2期33卷 355-364页

作者： Huimin XIANG Ni LAN fugang wang Benliang ZHAO Hui WEI Jiaen ZHANG Guangdong Provincial Key Laboratory of Eco-Circular Agriculture South China Agricultural UniversityGuangzhou 510642(China) Key Laboratory of Agro-Environment in the Tropics Ministry of AgricultureCollege of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642(China) Guangdong Engineering Research Center for Modern Eco-Agriculture and Circular Agriculture Guangzhou 510642(China) Key Laboratory of Agroecology and Rural Environment of Guangdong Regular Higher Education Institutions South China Agricultural UniversityGuangzhou 510642(China)

Cadmium(Cd)pollution affects plant growth and poses a serious threat to food safety and human ***-contaminated rice is assumed to be the main source of Cd exposure to humans,with grave health *** is an efficient,cost-effective,and eco-friendly approach to minimize Cd accumulation in ***,research on the effect of rice intercropping with wetland plants that exhibit great capacity for phytoremediation in decreasing Cd concentrations in paddies is limited.A pot experiment in greenhouse was conducted to evaluate the effect of rice intercropping with two wetland plants(Pontederia cordata and Canna indica)under different soil Cd levels(0,1,10,and 25 mg kg^(-1))on rice growth and Cd accumulation and *** results showed that rice intercropping with the two wetland plants significantly improved plant height,tiller,and biomass of rice,but reduced Cd bioconcentration factors(BCFs)and Cd concentrations in rice and wetland *** with rice monocropping,the BCF in rice grain under 25 mg kg^(-1)soil Cd level significantly decreased by 54.39%and 59.65%in the systems of rice intercropping with *** and ***,*** addition,intercropping inhibited the increase in BCFs in rice and wetland plants under increasing soil Cd *** conclusion,the systems of rice intercropping with *** and *** can be considered two new and effective approaches for ameliorating Cd pollution in paddies,as well as minimizing Cd accumulation in rice and improving food *** the two intercropping systems,rice intercropping with *** performed better than intercropping with ***.

关键词： bioconcentration factor Cd pollution Cd translocation phytoremediation transfer factor

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EFFECT OF GRAIN BOUNDARY CARBIDE ON CREEP CRACK GROWTH IN Fe-Cr15-Ni25 ALLOY

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Acta Metallurgica Sinica(English Letters) 1992年第1期5卷 48-51页

作者： wang, fugang Zhu, Suming Zhu, Shijie Ren, Xiaomin Tan, Yi Zhang, Junshan Dalian Univ of Technology Dalian China

Creep crack growth behavior of Fe-Cr15-Ni25 alloys with different grain boundary features has been *** nucleate at triple junctions of grain boundaries for the single phase alloy and at grain boundary carbide for the alloy with grain boundary *** bounda- ry carbide particles are obstacles to cavity growth and coalescence,and therefore increase the creep crack growth resistance greatly.

关键词： creep crack growth grain boundary carbide cavity Fe-Cr15-Ni25 alloy

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Status and trend of hydrogeological experiments concerning the side-wall flow effect in porous media

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Chinese Science Bulletin 2014年第8期59卷 715-721页

作者： fugang wang Zhenkai Gao Yilin Yuan Jing Jing Xinxin Geng Yuqing Cao Key Laboratory of Groundwater Resources and Environment Ministry of Education Jilin University

Hydrogeological experiments provide an important means to understand groundwater seepage and solute transport *** hydrogeological parameters can be obtained for use in assessing groundwater *** current porous-media research,studies of side-wall flow are in a preliminary and qualitative phase,and lack systematic and comprehensive ***-wall flow refers to the non-uniform infiltration and solute transport that occurs near the seepage device *** dynamics depends on the fluid under the specific hydraulic conditions,physical properties and chemical composition,medium permeability,the roughness of the side wall,geometric features,and physical *** phenomena not only occur in indoor water flows and solute transport,but also under natural conditions in the ***-wall flow has features both in common as well as distinct from preferential *** porous-media experiments,once side-wall flow commences,it affects the groundwater flow field and chemistry field,resulting in parameter values deviating from actual *** on a comprehensive analysis of the influence of side-wall flow,a definition of the side-wall flow effect in porous media is *** directions of research are identified concerning side-wall flow:the mechanism of the side-wall flows effect,the study of its quantitative impact on seepage flow and solute transport,and the methods and measures that need to be taken in hydrogeological experiments to reduce(or prevent)side-wall flow development.

关键词：水文地质试验多孔介质流量地下水渗流流体动力学状态水文地质参数溶质运移

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Effect of movability of water on the low-velocity pre-Darcy flow in clay soil

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3299-3310页

作者： Hui Cheng fugang wang Shengwei Li Xiaotong Guan Guohua Yang Zhongle Cheng Ceting Yu Yilong Yuan Guanhong Feng Key Laboratory of Groundwater Resources and Environment Ministry of EducationJilin UniversityChangchun130012China Jilin Provincial Key Laboratory of Water Resources and Water Environment Jilin UniversityChangchun130012China Chengdu Center China Geological SurveyChengdu610081China

Water seepage in soil is a fundamental problem involving various scientific and engineering *** to the literature,low-velocity water seepage in low-permeability porous media,such as clay,does not follow Darcy's law,also known as pre-Darcy *** formation of immovable water due to water adsorption on the pore wall is believed to be responsible for the formation of pre-Darcy ***,this view lacks direct solid *** investigate the pre-Darcy water flow in clay,head permeability experiments are conducted on six clay samples with different *** results indicate that water seepage in clay at low hydraulic gradients does not follow Darcy's law.A clear nonlinear relationship between flow velocity and hydraulic gradient is *** flow in clay can be divided into the pre-Darcy flow and Darcy flow regions by the critical hydraulic gradient,which is 10-12 for the Albic soil with dry density between 1.3 g/cm^(3)and 1.8 g/cm^(3).According to the disjoining pressure theory,immovable water due to water adsorption on the pore wall is the primary reason for water flow deviating from Darcy's law in *** results indicate that the percentage of movable water ranges from 39.7%to 59.3%for the six samples at a hydraulic gradient of *** the hydraulic gradient increases,the percentage of moveable water also ***,there is a strong correlation between the percentage of movable water and the variation in hydraulic conductivity with the hydraulic ***,a quantitative relationship between the percentage of movable water and the hydraulic conductivity has been *** results of this study suggest that water adsorption on the pore wall not only affects the water movability,but is also closely related to the pre-Darcy flow phenomenon in clay.

关键词： Pre-Darcy flow Clay Critical hydraulic gradient Water movability analysis

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A Numerical Simulation Study of Temperature and Pressure Effects on the Breakthrough Pressure of CO_(2)in Unsaturated Low-permeability Rock Core

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Acta Geologica Sinica(English Edition) 2023年第3期97卷 911-924页

作者： HU Zhikai LI Yi LI Qi DIAO Yujie MA Xin LIU Hejuan FENG Guanhong wang fugang YU Qingchun Key Laboratory of Coast Civil Engineering Structure and Safety of Education Ministry School of Civil EngineeringTianjin UniversityTianjin 300350China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China Key Laboratory of Carbon Dioxide Geological Storage Center for Hydrogeology and Environmental Geology SurveyChina Geological SurveyBaodingHebei 071051China Key Laboratory of Groundwater Resources and Environment(Jilin University) Ministry of EducationChangchun 130021China MOE Key Laboratory of Groundwater Circulation and Environmental Evolution China University of Geosciences(Beijing)Beijing 100083China

Gas breakthrough pressure is a key parameter to evaluate the sealing capacity of caprock,and it also plays important roles in safety and capacity of CO_(2)geological *** on the published experimental results,we present numerical simulations on CO_(2)breakthrough pressure in unsaturated low-permeability rock under 9 multiple P-T conditions(which can keep CO_(2)in gaseous,liquid and supercritical states)and thus,a numerical method which can be used to accurately predict CO_(2)breakthrough pressure on rock-core scale is *** simulation results show that CO_(2)breakthrough pressure and breakthrough time are exponential correlated with P-T ***,pressure has stronger effects on experimental results than that of ***,we performed sensitivity studies on the pore distribution indexλ(0.6,0.7,0.8,and 0.9)in van Genuchten-Muale *** show that with the increase ofλ,CO_(2)breakthrough pressure and breakthrough time both show decreasing *** other words,the larger the value ofλis,the better the permeability of the caprock is,and the worse the CO_(2)sealing capacity *** numerical method established in this study can provide an important reference for the prediction of gas breakthrough pressure on rock-core scale and for related numerical studies.

关键词： CO_(2)geological storage CO_(2)breakthrough pressure unsaturated low-permeability rock multiple P-T conditions numerical simulation

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EFFECT OF INTERGRANULAR CARBIDES ON CREEP RUPTURE PROPERTIES OF Fe-15Cr-25Ni ALLOY

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Acta Metallurgica Sinica(English Letters) 1992年第4期5卷 269-271页

作者： LI Pei’en Shanghai Jiaotong University,Shanghai,ChinaYE Baorui ZHANG Junshan wang fugang JIN Junze Dalian University of Technology,Dalian,China Shanghai Jiaotong Univ Shanghai China

The intergranular carbides may significantly increase rupture life and ductility of the Fe-15Cr-25Ni *** seems due to the grain boundary sliding and diffusion hindered by precipitation of intergranular carbides,so the... 详细信息

关键词： intergranular carbide creep rupture Fe-15Cr-25Ni alloy

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基于TRIZ理论的油炸薯片中丙烯酰胺含量的测定

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中国粮油学报 2013年第3期28卷 117-122页

作者：何鹏王成琳王福刚齐齐哈尔大学通信与电子工程学院齐齐哈尔161006

根据TRIZ创新理论,提出一种新的油炸薯片中丙烯酰胺含量的测定方法。计算机视觉系统中的图像采集装置每间隔1 min采集刚炸好薯片的双面图像,在Lab颜色空间中,用提出的图像滤波、分割和颜色测量算法从双面图像中提取目标薯片、测量整体... 详细信息

根据TRIZ创新理论,提出一种新的油炸薯片中丙烯酰胺含量的测定方法。计算机视觉系统中的图像采集装置每间隔1 min采集刚炸好薯片的双面图像,在Lab颜色空间中,用提出的图像滤波、分割和颜色测量算法从双面图像中提取目标薯片、测量整体薯片的颜色平均值,同时对相应薯片中的丙烯酰胺含量值做气相色谱-质谱法测定。对数据进行分析,发现薯片双面a平均值和其丙烯酰胺含量值之间有很强的相关性(R2=0.971),建立了两者之间的线性回归方程。利用所提出的方法测定市场上出售的10个不同品牌薯片的丙烯酰胺含量值,与标准化学方法测定值之间的最大相对误差仅为4.94%,说明该方法准确可行。

关键词： TRIZ理论油炸薯片丙烯酰胺测定值图像采集装置计算机视觉系统颜色空间线性回归方程

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High Temperature Creep behaviour of a Si_3N_4 Whisker Reinforced Al-Fe-V-Si Composite

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Journal of Materials Science & Technology 1998年第6期14卷 527-532页

作者： Liangming PENG Shijie ZHU Haoran CHEN and fugang wang(Dept. of Materials Engineering,Dalian University of Technology, Dalian 116023, China)Zongyi MA and Jing BI(Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, China) Dept. of Materials Engineering Dalian University of Technology Dalian 116023 China Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The creep behaviour of β-Si3N4 whisker reinforced Al-8.5Fe-1.3V-1.7Si composite has been investigated at the temperature 773 and 823 K. The results are characterized by high stress exponent and high apparent creep activation energy The creep data can be interpreted based on the incorporation of a threshold Stress and a load transfer coefficient into the power-law creep equation. A good correlation between the normalized creep rate and normalized effective stress is available which demonstrates that the creep behaviour of both the alloy and the composite is controlled by the matrix lattice self-diffusion in AI. EXamination on microstructure shows that edge dislocations exist at the interfaces between two adjacent whiskers and the intedeces emit edge dislocations in parallel paired-columns.

关键词： Si Al Fe High Temperature Creep behaviour of a Si3N4 Whisker Reinforced Al-Fe-V-Si Composite

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