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Soil Organic Carbon Density in Hebei Province, China: Estimates and Uncertainty

Pedosphere 2005年第3期15卷 293-300页

作者： ZHAOYong-Cun SHIXue-Zheng yudong-sheng T.F.PAGELLA SUNWei-Xia XUXiang-Hua StateKeyLaboratoryofSoilandSustainableAgriculture InstituteofSoilScienceChineseAcademyofSciencesNanjing210008（China）／／GraduateSchoolofChineseAcademyofSciencesBeijing100039（China） StateKeyLaboratoryofSoilandSustainableAgriculture InstituteofSoilScienceChineseAcademyofSciencesNanjing210008（China）／／SchoolofAgriculturalandForestSciencesUniversityofWalesBangor（UK） StateKeyLaboratoryofSoilandSustainableAgriculture InstituteofSoilScienceChineseAcademyofSciencesNanjing210008（China） SchoolofAgriculturalandForestSciences UniversityofWalesBangor（UK） DepartmentofEnvironmentalEngineering ZhejiangUniversityHangzhou310029（China）

In order to improve the precision of soil organic carbon (SOC) estimates, the sources of uncertainty in soil organic carbon density (SOCD) estimates and SOC stocks were examined using 363 soil profiles in Hebei Province, China, with three methods: the soil profile statistics (SPS), GIS-based soil type (GST), and kriging interpolation (KI). The GST method, utilizing both pedological professional knowledge and GIS technology, was considered the most accurate method of the three estimations, with SOCD estimates for SPS 10% lower and KI 10% higher. The SOCD range for GST was 84% wider than KI as KI smoothing effect narrowed the SOCD range. Nevertheless, the coefficient of variation for SOCD with KI (41.7%) was less than GST and SPS. Comparing SOCD’s lower estimates for SPS versus GST, the major sources of uncertainty were the conflicting area of proportional relations. Meanwhile, the fewer number of soil profiles and the necessity of using the smoothing effect with KI were its sources of uncertainty. Moreover, for local detailed variations of SOCD, GST was more advantageous in reflecting the distribution pattern than KI.

关键词： professional pedological knowledge-based database (PKD) soil organic carbon (SOC) soil profile database (SPD) soil profile statistics (SPS) uncertainty

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Using GIS Spatial Distribution to Predict Soil Organic Carbon in Subtropical China

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Pedosphere 2004年第4期14卷 425-431页

作者： CHENGXian-Fu SHIXue-Zheng yudong-sheng PANXian-Zhang WANGHong-Jie SUNWei-Xia StateKeyLaboratoryofSoilandSustainableAgriculture InstituteofSoilScienceChineseAcademyofSciencesNanjing210008（China）. Departmentofgeography AnhuiNormalUniversityWuhu241000（China）

Spatial distribution of organic carbon in soils is difficult to estimatebecause of inherent spatial variability and insufficient data. A soil-landscape model for a region,based on 151 samples for parent material and topographic factors, was established using a GISspatial analysis technique and a digital elevation model (DEM) to reveal spatial distributioncharacteristics of soil organic carbon (SOC). Correlations between organic carbon and topographicfactors were analyzed and a regression model was established to predict SOC content. Results forsurface soils (0-20 cm) showed that the average SOC content was 12.8 g kg^(-1), with the SOC contentbetween 6 and 12 g kg^(-1) occupying the largest area and SOC over 24 g kg^(-1) the smallest. Also,soils derived from phyllite were the highest in the SOC content and area, while soils developed onpurple shale the lowest. Although parent material, elevation, and slope exposure were allsignificant topographic variables (P < 0.01), slope exposure had the highest correlation to SOCcontent (r = 0.66). Using a multiple regression model (R^2 = 0.611) and DEM (with a 30 m X 30 mgrid), spatial distribution of SOC could be forecasted.

关键词： digital elevation model parent material regression model soil organiccarbon topography

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Functional Rehabilitation of the "Soil Reservoir"in Degraded Soils to Control Floods in the Yangtze River Watershed

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Pedosphere 2004年第1期14卷 1-8页

作者： SHIXue-Zheng LIANGYin yudong-sheng PANXian-Zhang[ E.D.WARNER WANGHong-Jie InstituteofSoilScience ChineseAcademyofSciencesNanjing210008（China） EnvironmentalResourcesResearchInstitute ThePennsylvaniaStateUniversityUniversityPark（USA）

The reasons for the Yangtze River flood calamity in 1998 are briefly introduced. The authors believe that using a 'soil reservoir' concept is an important means to help control flooding of the Yangtze River.A 'soil reservoir' has a large potential storage capacity and its water can be rapidly 'discharged' into the underground water in a timely fashion. The eroded, infertile soils of the Yangtze River Watershed are currently an obstacle to efficient operation of the 'soil reservoir'. The storage capacity of this 'soil reservoir'has been severely hampered due to intensive soil erosion and the formation of soil crusts. Therefore, possible measures to control floods in the Yangtze River Watershed include: rehabilitating the vegetation to preserve soil and water on the eroded infertile soils, enhancing infiltration of the different soil types, and utilizing the large 'soil reservoir' of the upper reaches of the Yangtze River.

关键词： flood calamity soil erosion 'soil reservoir' the yangtze river watershed

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Quantitative Effects of Velocity and Residual Pressure Level on Aerodynamic Noise of Ultra-High-Speed Maglev Trains

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Fluid Dynamics & Materials Processing 2025年第1期21卷 205-220页

作者： Lanxi Zhang Yuming Peng yudong Wu School of Mechanical Engineering Southwest Jiaotong UniversityChengdu610031China School of Intelligent Manufacturing Chengdu Technological UniversityChengdu610031China

The challenge of aerodynamic noise is a key obstacle in the advancement of low-pressure tube ultra-high-speed maglev transportation,demanding urgent *** study utilizes a broadband noise source model to perform a quantitative analysis of the aerodynamic noise produced by ultra-high-speed maglev trains operating in low-pressure ***,an external flow field calculation model for the ultra-high-speed maglev train is ***,numerical simulations based on the broadband noise source model are used to examine the noise *** impact of the train speed and pressure level on noise generation is investigated ***,a correlation formula is *** results reveal that the amplitude of sound source changes in the streamlined region of the head and tail cars of the train is large,and the amplitude of changes for the middle car is *** noise source strength increases with speed,with a quadrupole noise source becoming dominant when the train speed exceeds 600 km/*** a speed of 1000 km/h,the noise source intensity from the streamlined area at the rear of the train overcomes that at the ***,the noise source decreases as the pressure level in the tube *** the pressure level drops to 0.01 atm,the quadrupole noise source intensity of a train running at 600 km/h significantly weakens and falls below that of the dipole noise source.

关键词： Low-pressure tube aerodynamic noise train speed quantitative analysis

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Defect Engineering with Rational Dopants Modulation for High‑Temperature Energy Harvesting in Lead‑Free Piezoceramics

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Nano-Micro Letters 2025年第3期17卷 87-101页

作者： Kaibiao Xi Jianzhe Guo Mupeng Zheng Mankang Zhu yudong Hou Key Laboratory of Advanced Functional Materials Ministry of EducationCollege of Materials Science and EngineeringBeijing University of TechnologyBeijing 100124People’s Republic of China

High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless ***,simultaneously excellent performances,including high figure of merit(FOM),insulation resistivity(ρ)and depolarization temperature(Td)are indispensable but hard to achieve in lead-free piezoceramics,especially operating at 250°C has not been reported ***,well-balanced performances are achieved in BiFeO3–BaTiO3 ceramics via innovative defect engineering with respect to delicate manganese *** to the synergistic effect of enhancing electrostrictive coefficient by polarization configuration optimization,regulating iron ion oxidation state by high valence manganese ion and stabilizing domain orientation by defect dipole,comprehensive excellent electrical performances(Td=340°C,ρ250°C>10^(7)Ωcm and FOM_(250°C)=4905×10^(–15)m^(2)N^(−1))are realized at the solid solubility limit of manganese *** HT-PEHs assembled using the rationally designed piezoceramic can allow for fast charging of commercial electrolytic capacitor at 250°C with high energy conversion efficiency(η=11.43%).These characteristics demonstrate that defect engineering tailored BF-BT can satisfy high-end HT-PEHs requirements,paving a new way in developing selfpowered wireless sensors working in HT environments.

关键词： Lead-free piezoceramic Defect engineering Dopants modulation High-temperature Piezoelectric energy harvester

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Combined biochar and wheat-derived endophytic bacteria reduces cadmium uptake in wheat grains in a metal-polluted soil

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Journal of Environmental Sciences 2025年第1期147卷 165-178页

作者： Zhihui Xiong Yaping Wang Linyan He Qi sheng Xiafang sheng College of Life Sciences Key Laboratory of Agricultural and Environmental MicrobiologyMinistry of AgricultureNanjing Agricultural UniversityNanjing 210095China

In this study,two wheat-derived cadmium(Cd)-immobilizing endophytic Pseudomonas paralactis M14 and Priestia megaterium R27 were evaluated for their effects on wheat tissue Cd uptake under hydroponic ***,the impacts of the biochar(BC),M14+R27(MR),and BC+MR treatments on wheat Cd uptake and the mechanisms involved were investigated at the jointing,heading,and mature stages of wheat plants under field-plot conditions.A hydroponic experiment showed that the MR treatment significantly decreased the above-ground tissue Cd content compared with theM14 or R27 *** BC+MRtreatment reduced the grain Cd content by 51.5%-67.7%and Cd translocation factor at the mature stage of wheat plants and increased the organic matter-bound Cd content by 31%-75%in the rhizosphere soils compared with the BC or MR *** with the BC or MR treatment,the relative abundances of the biomarkers associated with Gemmatimonas,Altererythrobacter,Gammaproteobacteria,Xanthomonadaceae,Phenylobacterium,and Nocardioides in the BC+MR-treated rhizosphere microbiome decreased and negatively correlated with the organic matter-bound Cd *** the BC+MR-treated root interior microbiome,the relative abundance of the biomarker belonging to Exiguobacterium increased and negatively correlated with the Cd translocation factor,while the relative abundance of the biomarker belonging to Pseudonocardiaceae decreased and positively correlated with the Cd translocation *** findings suggested that the BC+MR treatment reduced Cd availability and Cd transfer through affecting the abundances of these specific biomarkers in the rhizosphere soil and root interior microbiomes,leading to decreased wheat grain Cd uptake in the contaminated soil.

关键词： Cd-immobilizing endophytic bacteria Cd-contaminated soil Biochar+endophytic bacteria Grain Cd uptake Specific biomarkers

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Synthesiztion of Radiation-inducible Promoter and Identification of Its Radiation-inducibility

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中国口腔颌面外科杂志 2008年第B5期6卷 138-138页

作者： yudong sheng Huanghong Zhang Department of Stomatology SUNChinaOral MaxillofacialYat-sen UniversitySurgery Hospital of Guangzhou 510055

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产品全生命周期过程知识树导航重用研究

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现代制造工程 2017年第1期 76-81页

作者：冯全华张东民盛育东张宏上海应用技术大学机械工程学院上海201418 上海徐工工程机械有限公司上海201412

复杂机械产品的开发具有知识密集型的特点,知识重用策略在开发中起着重要作用。对机械产品全生命周期中容易忽略的过程知识进行研究,面向产品全生命周期和自身结构,构建产品过程知识本体,将大粒度的本体知识细化成含有知识节点和知识点... 详细信息

复杂机械产品的开发具有知识密集型的特点,知识重用策略在开发中起着重要作用。对机械产品全生命周期中容易忽略的过程知识进行研究,面向产品全生命周期和自身结构,构建产品过程知识本体,将大粒度的本体知识细化成含有知识节点和知识点的知识树。对知识树映射的过程知识进行建模,并通过知识树导航和关键词检索重用产品全生命周期过程知识,满足了不同技术层次开发者的需求。以摊铺机为例,开发了基于知识树导航的摊铺机全生命周期过程知识重用系统,验证了方法的可行性。

关键词：过程知识知识建模知识重用知识树导航关键词检索

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A logistic-Lasso-regression-based seismic fragility analysis method for electrical equipment considering structural and seismic parameter uncertainty

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 169-186页

作者： Cui Jiawei Che Ailan Li sheng Cheng Yongfeng Key Lab of Structures Dynamic Behavior and Control of the Ministry of Education School of Civil EngineeringHarbin Institute of TechnologyHarbin 150094China School of Ocean and Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China China Electric Power Research Institute Beijing 100055China

Damage to electrical equipment in an earthquake can lead to power outage of power *** fragility analysis is a common method to assess the seismic reliability of electrical *** further guarantee the efficiency of analysis,multi-source uncertainties including the structure itself and seismic excitation need to be considered.A method for seismic fragility analysis that reflects structural and seismic parameter uncertainty was developed in this *** proposed method used a random sampling method based on Latin hypercube sampling(LHS)to account for the structure parameter uncertainty and the group structure characteristics of electrical ***,logistic Lasso regression(LLR)was used to find the seismic fragility surface based on double ground motion intensity measures(IM).The seismic fragility based on the finite element model of an±1000 kV main transformer(UHVMT)was analyzed using the proposed *** results show that the seismic fragility function obtained by this method can be used to construct the relationship between the uncertainty parameters and the failure *** seismic fragility surface did not only provide the probabilities of seismic damage states under different IMs,but also had better stability than the fragility ***,the sensitivity analysis of the structural parameters revealed that the elastic module of the bushing and the height of the high-voltage bushing may have a greater influence.

关键词： seismic fragility uncertainty logistic lasso regression ±1000 kV main transformer sensitivity analysis

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Modeling Bivariate Distribution of Wind Speed and Wind Shear for Height-Dependent Offshore Wind Energy Assessment

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Journal of Ocean University of China 2025年第1期24卷 40-62页

作者： YANG Zihao DONG sheng College of Engineering Ocean University of ChinaQingdao 266404China

A joint statistical model of wind speed and wind shear is critical for height-dependent wind resource characteristic ***,given the different atmospheric conditions that may be involved,the statistical distribution of the two variables may show multimodal *** this work,a finite mixture bivariate statistical model was designed to describe the statistical properties,which is composed of several components,each with a Weibull distribution and a normal distribution for wind speed and wind shear,respectively,with a Gaussian copula to describe the dependency structure between the two *** confirm the developed model,reanalysis data from six positions in the coastal sea areas of China were *** results disclosed that the developed joint statistical model can accurately capture the different multimodal structures presented in all the bivariate samples under mixed atmospheric conditions,giving acceptable predictions of the joint probability *** consideration of wind shear coefficient variation is crucial in estimating height-dependent wind resource ***,unlike traditional methods that are limited to specific hub heights,the model developed here can estimate wind energy potential across different hub heights,enhancing the economic viability assessment of wind power projects.

关键词： wind shear coefficient wind speed mixed atmospheric conditions mixture bivariate statistical model height-dependent wind resource characteristics

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