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Modeling Soil Water Retention Curve with a Fractal Method

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Pedosphere 2006年第2期16卷 137-146页

作者： HUANG Guan-Hua zhang ren-duo HUANG Quan-Zhong Department of Irrigation and Drainage Chinese-Israeli International Center for Research and Training in Agriculture China Agricultural University Beijing 100083 （China）. Department of renewable Resources University of Wyoming Laramie WY 82071-3354 （USA）

Many empirical models have been developed to describe the soil water retention curve (SWRC). In this study, a fractal model for SWRC was derived with a specially constructed Menger sponge to describe the fractal scaling behavior of soil; relationships were established among the fractal dimension of SWRC, the fractal dimension of soil mass, and soil texture; and the model was used to estimate SWRC with the estimated results being compared to experimental data for verification. The derived fractal model was in a power-law form, similar to the Brooks-Corey and Campbell empirical functions. Experimental data of particle size distribution (PSD), texture, and soil water retention for 10 soils collected at different places in China were used to estimate the fractal dimension of SWRC and the mass fractal dimension. The fractal dimension of SWRC and the mass fractal dimension were linearly related. Also, both of the fractal dimensions were dependent on soil texture, i.e., clay and sand contents. Expressions were proposed to quantify the relationships. Based on the relationships, four methods were used to determine the fractal dimension of SWRC and the model was applied to estimate soil water content at a wide range of tension values. The estimated results compared well with the measured data having relative errors less than 10% for over 60% of the measurements. Thus, this model, estimating the fractal dimension using soil textural data, offered an alternative for predicting SWRC.

关键词： fractal dimension soil texture soil water retention curve

Characterization of Strain Pseudomonas sp. Q1 in Microbial Fuel Cell for Treatment of Quinoline-Contaminated Water

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Pedosphere 2012年第4期22卷 528-535页

作者： zhang Cui-Ping CHEN Shah-Shan LIU Guang-Li zhang ren-duo XIE Jian South China Sea Marine Engineering and Environment Institute SOAGuangzhou 510300(China) School of Environmental Science and Engineering Sun Yat-sen UniversityGuangzhou 510275(China) Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology Guangzhou 510275(China)

To find new strain in the microbial fuel cell (MFC) for quinoline removal from wastewater and soil, a facultative anaerobic bacterium strain was isolated from the anode of MFC, utilizing quinoline as the carbon source and electron donor. Based on the 16S rRNA sequence analysis, the bacterium strain was Gram-negative and identified as Pseudomonas sp. Q1 according to its morphology and physiochemical properties. The strain was inoculated into a double-chambered MFC using various quinoline concentrations (0, 50, 75, 86, 100, 150, 200 and 300 mg L-1 ) combining with 300 mg L-1 glucose as the fuel. Results showed that electricity was generated from the MFC, in which quinoline was degraded simultaneously. The values of Coulombic efficiency (CE) increased with the increase of quinoline concentrations from 0 to 100 mg L-1 then decreased with the increase of quinoline concentration from 100 to 300 mg L-1 , and the maximum CE 36.7% was obtained at the quinoline concentration of 100 mg L-1 . The cyclic voltammetry analysis suggested that the mechanism of electron transfer was through excreting mediators produced by the strain Q1. The MFC should be a potential method for the treatment of quinoline-contaminated water and soil.

关键词： bacterium strain biodegradation electron transfer power generation glucose

推求Gardner-Russo持水曲线模型参数的简单入渗法

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水利学报 2006年第9期37卷 1114-1121页

作者：邹朝望薛绪掌张仁铎武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072 国家农业信息化工程技术研究中心北京100089 中山大学环境科学与工程学院广东广州510275

本文基于水平一维非饱和土壤水分运动规律,推求了Gardner-Russo持水曲线模型参数,获得了水平一维非饱和土壤水分运动中累积入渗量、入渗率、湿润峰、入渗时间之间的理论关系.用模拟的结果进行拟合,其决定系数为0.9969～0.9997.当获得土... 详细信息

本文基于水平一维非饱和土壤水分运动规律,推求了Gardner-Russo持水曲线模型参数,获得了水平一维非饱和土壤水分运动中累积入渗量、入渗率、湿润峰、入渗时间之间的理论关系.用模拟的结果进行拟合,其决定系数为0.9969～0.9997.当获得土壤饱和体积含水率、初始体积含水率、残余体积含水率和土壤饱和导水率,基于这些理论关系实现了Gardner-Russo模型曲线特征参数的求解.利用数值模拟数据和实验数据检验该方法,将用此方法估计的参数值与理论值进行比较,并进行了模型中参数的敏感性分析,结果表明本研究所求得的参数有较高的精度,为土壤水分运动参数求解提供了一种简单的土壤水分瞬时入渗法.

关键词：土壤水分渗流运动持水曲线 Gardner-Russo模型参数数值模拟

Bioremediation of Contaminated Soil and Water

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Pedosphere 2012年第4期22卷 425-425页

作者： QIU Rong-Liang Jérôme GUERIF zhang ren-duo School of Environmental Science and Engineering Sun Yat-sen University GuangzhouChina Environment&Agronomy Division INRA AvignonFrance

Bioremediation of contaminated soil and water is an emerging technology in the field of environmental science and *** uses biological organisms such as bacteria,fungi or even plants to aid in degrading and removing hazardous substances from the contaminated *** has become a hot spot of research because of its characteristics such as low energy consumption,high efficiency and environmental ***,it is a challenging area that requires researchers' further commitment.

关键词：生物修复污染土壤水环境安全环境科学有害物质研究人员污染区

用盘式负压入渗仪计算土壤水动力参数的改进方法

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水利学报 2005年第8期36卷 1007-1013页

作者：张艳张仁铎薛绪掌邹朝望武汉大学水利水电学院湖北武汉430072 国家农业信息化工程技术研究中心北京100089

本研究为根据盘式负压入渗仪测定的入渗数据计算土壤水动力参数的一种新方法。该方法是在已有方法结构不变的情况下,引入重力对入渗的影响,发展得到的新模型。为了检验新方法,分别用各种不同模型计算用数值模拟及田间试验得到的不同土... 详细信息

本研究为根据盘式负压入渗仪测定的入渗数据计算土壤水动力参数的一种新方法。该方法是在已有方法结构不变的情况下,引入重力对入渗的影响,发展得到的新模型。为了检验新方法,分别用各种不同模型计算用数值模拟及田间试验得到的不同土壤、盘径、水头压力条件下的入渗数据并进行比较。结果表明,相对于其他方法,新方法不仅对小盘径盘式负压入渗仪得到的入渗数据适用,更适用于大盘径盘式负压入渗仪得到的入渗数据,计算的导水率能在短时间内趋于常量,且计算结果比其他方法精度更高,是一种合理可靠的计算方法。

关键词：盘式负压入渗仪导水率宏观毛管上升高度

多孔介质中非均匀流动特性的染色示踪试验研究

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水科学进展 2007年第5期18卷 662-667页

作者：王康张仁铎缴锡云武汉大学水利水电学院水资源与水电工程科学国家重点实验室湖北武汉430072 中山大学环境科学与工程学院广东广州510275 河海大学水文水资源与水利工程科学国家重点实验室江苏南京210098

通过土壤染色剂进行的4组试验,对不同介质结构条件下的水流和溶质非均匀运动规律,非均匀流动变异信息分布特征关系以及全局性非均匀流动示踪方法进行了研究。结果表明,即使在相对比较均匀的介质条件下,流动也表现出明显的非均匀特性;对... 详细信息

通过土壤染色剂进行的4组试验,对不同介质结构条件下的水流和溶质非均匀运动规律,非均匀流动变异信息分布特征关系以及全局性非均匀流动示踪方法进行了研究。结果表明,即使在相对比较均匀的介质条件下,流动也表现出明显的非均匀特性;对数正态分布能够较好的反映水流的运动分布模式,相比水流运动,溶质的运动和分布规律明显不同,表现出更多的不确定性和变异性。

关键词：染色示踪剂多孔介质图像标准化非均匀流动浓度分布模式

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多孔介质中非均匀流动模式信息特性聚类分析

水科学进展 2008年第5期19卷 714-721页

作者：王康张仁铎周祖昊武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072 中山大学环境科学与工程学院广东广州510275 中国水利水电科学研究院水资源研究所北京100044

研究了多孔介质中非均匀流动描述方法和流动模式信息特性。依据流道宽度分布信息,对4组染色示踪试验的垂直剖面流动区域进行水平分层,将流道统计信息作为变量,对水平层进行系统聚类分析。结果表明,染色比例和染色区域内流动通道宽度分... 详细信息

研究了多孔介质中非均匀流动描述方法和流动模式信息特性。依据流道宽度分布信息,对4组染色示踪试验的垂直剖面流动区域进行水平分层,将流道统计信息作为变量,对水平层进行系统聚类分析。结果表明,染色比例和染色区域内流动通道宽度分布是流动聚类分区的主要影响因素。聚类数目为3和8情况下,能够最为有效地表征非均匀流动模式。以垂直方向流动为主,且流动通道连续的情况下,流动分区主要包括全局性均匀流、局部均匀流、均匀流向非均匀流过渡区,以及优先流区。水平方向流动特性较为显著的情况下,则存在多个均匀流向非均匀流动的过渡区。

关键词：多孔介质非均匀流动染色示踪试验聚类分析信息模式

Molecular dynamics simulations of helium transport through inorganic mineral nanopores

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Science China Earth Sciences 2025年第1期68卷 237-252页

作者： Dandan SONG Ping GUAN Chi zhang Jiahao ren School of Earth and Space Sciences Peking University

Helium transport through nanoscale inorganic mineral pores and pore throats is essential for its overall migration. To elucidate helium's transport dynamics within nanopores, we employed equilibrium and non-equilibrium molecular dynamics simulations to investigate helium's static self-diffusion and pressure-driven flow in quartz slit-shaped nanopores. We also introduced water and various gases, including hydrogen, methane, ethane, nitrogen, and carbon dioxide, into the nanopores to assess their influence on helium transport. Our findings indicate minimal helium adsorption on quartz pore surfaces. Under conditions where the pore size is less than 5 nm and the pressure under 10 MPa, environmental factors markedly influence helium diffusion. Large pore sizes, high temperatures, and low gas pressures enhance helium desorption and facilitate faster diffusion. We observed a positive correlation between helium flow velocity and factors such as pore size, pressure gradient, and surface smoothness of the pores. Notably, the presence of pore water and carrier gases in quartz nanopores, which diffuse more slowly than helium, tends to reduce helium surface adsorption and slow its diffusion. Among the carrier gases studied, nitrogen showed similar adsorption capacity, diffusivity, and stability to helium, while carbon dioxide displayed the highest adsorption capacity and the slowest diffusion rate, markedly differing from helium. Based on the simulation results, we concluded that water and carrier gases primarily function as transport mediums in helium migration, moving together with helium. Nitrogen, which shares similar properties with helium, effectively assists in this co-migration process. Conversely, carbon dioxide, due to its high adsorption capacity and slow diffusion, tends to be lost during co-migration. As a result, gas reservoirs with high nitrogen levels and low carbon dioxide levels are more likely to have higher helium concentrations. Additionally, the smaller por

关键词： Helium transport Slit nanopores Molecular dynamics simulations Diffusion Flow carriers

多孔介质中非均匀流活动性流场模型本构关系研究

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水利学报 2008年第2期39卷 151-157页

作者：李萼王康张仁铎盛丰中山大学环境科学与工程学院广东广州510275 武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072

本文在土壤染色示踪试验的基础上,对多孔介质活动性流场模型的本构关系进行了分析。在此基础上讨论了流动非均匀性和本构关系参数之间的关系。研究表明:土壤剖面不同深度和宽度处的染色比例值都增大时,活动性流场模型本构关系中的分形... 详细信息

本文在土壤染色示踪试验的基础上,对多孔介质活动性流场模型的本构关系进行了分析。在此基础上讨论了流动非均匀性和本构关系参数之间的关系。研究表明:土壤剖面不同深度和宽度处的染色比例值都增大时,活动性流场模型本构关系中的分形参数值减小;本构关系参数值和水流最大入渗深度与50%面积染色深度的比值及土壤剖面宽度处染色比例的最大值与最小值的比值均成正相关关系。此外,本文还利用黏土中的染色示踪试验数据分析了活动性流场模型本构关系参数的取值。

关键词：活动性流场模型连续性模型非均匀流动多孔介质分形本构关系