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基于模糊n-cell数的非线性投入产出模型解的存在性
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作者 陆星宇 叶国菊 刘尉 《湖北大学学报(自然科学版)》 CAS 2024年第2期225-232,共8页
将混合单调以及耦合不动点的概念引入到模糊n-cell数空间中,给出此空间上的混合单调型不动点定理。考虑到模糊n-cell数具有表示n维不确定信息的特点,将非线性投入产出模型与模糊n-cell数相结合,建立模糊非线性投入产出模型并给出相应的... 将混合单调以及耦合不动点的概念引入到模糊n-cell数空间中,给出此空间上的混合单调型不动点定理。考虑到模糊n-cell数具有表示n维不确定信息的特点,将非线性投入产出模型与模糊n-cell数相结合,建立模糊非线性投入产出模型并给出相应的平衡方程。最后利用本文中所给的不动点定理讨论此模型解存在的条件,验证模型的合理性。 展开更多
关键词 模糊n-cell数 混合单调 不动点定理 非线性投入产出模型
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Controlled-release fertilizer(CRF): A green fertilizer for controlling non-point contamination in agriculture 被引量:20
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作者 MAOXiao-yun SUNKe-jun WANGDe-han LIAOZong-wen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第2期181-184,共4页
Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas(N 2O) and eutrophication of water bodies. How to solve this problem has... Fertilizers contribute greatly to high yields but also result in environmental non-point contamination, including the emission of greenhouse gas(N 2O) and eutrophication of water bodies. How to solve this problem has become a serious challenge, especially for China as its high ecological pressure. Controlled-release fertilizer(CRF) has been developed to minimize the contamination while keeping high yield and has become a green fertilizer for agriculture. Several CRFs made with special coating technology were used for testing the fertilizer effects in yield and environment through pot experiment and field trial. The result indicated that the CRFs had higher N use efficiency, thus reducing N loss through leaching and volatilization while keeping higher yields. Comparing with imported standard CRFs, the test on CRFs showed similar fertilizer effect but with much lower cost. CRFs application is becoming a new approach for minimizing non-point contamination in agriculture. 展开更多
关键词 controlled-release fertilizer n use efficiency non-point contamination
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Determination of work-hardening exponent for sheet metal using three-point method 被引量:1
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作者 康达昌 田浩彬 刘现平 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第3期275-277,共3页
Three characteristic points in the deformation history of a fractured tensile specimen are selected tocalculate two values of n( n1 and n2 ) to represent the hardening ability of material during the homogeneous plas-t... Three characteristic points in the deformation history of a fractured tensile specimen are selected tocalculate two values of n( n1 and n2 ) to represent the hardening ability of material during the homogeneous plas-tic deformation and the following large plastic deformation. Experimental results obtained with mild streel andred copper show that n determined using the three-point method proposed is better to describe the hardening a-bility of material. It is therefore concluded that three-point method can be used to describe the hardening prop-erty of material during both homogeneous deformation and large plastic deformation. 展开更多
关键词 work-hardening exponent (n) Three-point method characteristic points tensile test
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关于N型映射的迭代和终于不动点
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作者 陈凯 石勇国 《纯粹数学与应用数学》 2024年第2期366-380,共15页
函数迭代通常会发生复杂的动力学现象,即使是简单的函数,甚至是逐段的线性函数的迭代都很复杂.通常计算出一个分段线性函数的n次迭代精确表达式非常困难.本文考虑N型映射的动力学性质,定义了一个关于N型映射的指标函数.利用这个指标函数... 函数迭代通常会发生复杂的动力学现象,即使是简单的函数,甚至是逐段的线性函数的迭代都很复杂.通常计算出一个分段线性函数的n次迭代精确表达式非常困难.本文考虑N型映射的动力学性质,定义了一个关于N型映射的指标函数.利用这个指标函数,本文给出了该映射n次迭代精确表达式,同时给出了终于不动点恰好第n步映到不动点的充分必要条件. 展开更多
关键词 n型映射 n阶迭代 终于不动点
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C_(4)F_(7)N/CO_(2)混合气体湿度检测技术研究
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作者 谢成 邵先军 +3 位作者 张伟 王鑫 丁五行 何毅帆 《高压电器》 CAS CSCD 北大核心 2024年第9期148-154,共7页
电气设备中C_(4)F_(7)N/CO_(2)混合绝缘气体的湿度水平影响气体的绝缘性能,定期检测湿度是日常运维工作之一。文中研究采用变电站日常运维中常规的冷镜式露点仪和阻容式湿度计对不同湿度的C_(4)F_(7)N/CO_(2)混合绝缘气体进行检测,实验... 电气设备中C_(4)F_(7)N/CO_(2)混合绝缘气体的湿度水平影响气体的绝缘性能,定期检测湿度是日常运维工作之一。文中研究采用变电站日常运维中常规的冷镜式露点仪和阻容式湿度计对不同湿度的C_(4)F_(7)N/CO_(2)混合绝缘气体进行检测,实验表明上述常规湿度检测仪器均不能直接应用于C_(4)F_(7)N/CO_(2)混合气体的湿度检测。文中将上述冷镜式露点仪进行技术改造后,采用标准湿度的C_(4)F_(7)N/CO_(2)混合气体对其进行准确度实验,结果表明,改造后的冷镜式露点仪的露点测量误差不超过±0.2℃,且在C_(4)F_(7)N比例不超过12%时可准确检测不低于150μL/L的湿度,满足C_(4)F_(7)N/CO_(2)混合气体电气设备的运维要求。上述阻容式湿度计经过C_(4)F_(7)N/CO_(2)混合气体湿度发生器重新标定后也可用于C_(4)F_(7)N/CO_(2)混合气体的湿度检测,露点测量误差不超过±2.0℃。 展开更多
关键词 C_(4)F_(7)n/CO_(2)混合气体 湿度检测 冷镜式露点仪 制冷温度控制
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m-degree Center-connecting Line of Finite Points Set and Its Properties 被引量:1
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作者 ZHOU Yong-guo 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第2期247-252,共6页
In this paper, we first give the concept of m-degree center-connecting line in n-dimensional Euclidean space Enand investigate its several properties, then we obtain the length of m-degree center-connecting line formu... In this paper, we first give the concept of m-degree center-connecting line in n-dimensional Euclidean space Enand investigate its several properties, then we obtain the length of m-degree center-connecting line formula in finite points set. As its application,we extend the Leibniz formula and length of medians formula in n-dimensional simplex to polytope. 展开更多
关键词 n-dimensional Euclidean space finite points set m-degree center-connectingline PROPERTIES
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A New Thioamide Derivative for Separation and Preconcentration of Multi Elements in Aquatic Environment by Cloud Point Extraction 被引量:1
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作者 Mohamed M. Hassanien Ali M. Hassan +1 位作者 Wael I. Mortada Ahmed A. El-Asmy 《American Journal of Analytical Chemistry》 2011年第6期697-709,共13页
2-(pyridine-2-yl)-N-p-chlorohydrazinecarbothioamide (HCPTS) was synthesized, characterized and successfully applied for the preconcentration of Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II) in wat... 2-(pyridine-2-yl)-N-p-chlorohydrazinecarbothioamide (HCPTS) was synthesized, characterized and successfully applied for the preconcentration of Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II) in water, blood, and urine samples prior to graphite furnace atomic absorption determination (GFAAS);Hg was determined by cold vapor technique. Under the optimum experimental conditions (i.e. pH = 8, 10–4 M of HCPTS, 0.05% w/v of Triton X-114), calibration graphs were linear in the range of 0.02 to 200 ng?mL–1 for Co(II), Cd(II), Pb(II) and Ni(II);0.03 to 200 ng?mL–1 for Cu(II);0.07 to 200 ng?mL–1 for Fe(II) and Zn(II) and 0.02 to 150 ng?mL–1 for Hg(II). The enrichment factors were 43, 51, 41, 46, 54, 40, 45 and 52 for Cu(II), Ni(II),Zn (II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II), respectively. The limit of detection were found to be 0.019, 0.094, 0.0514, 0.052, 0.0165, 0.047, 0.068 and 0.041 ng?mL–1 for Cu(II), Ni(II), Zn(II), Cd(II), Co(II), Pb(II), Fe(II), and Hg(II), respectively. The developed method was applied to the determination of these metal ions in water, blood and urine samples with satisfactory results. 展开更多
关键词 HEAVY Metals PRECOnCEnTRATIOn Cloud point Extraction 2-(Pyridine-2-Yl)-n-P-Chlorohydrazinecarbothioamide
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Point Correspondences between <i>N</i>+ 1 Hypersurfaces of Projective Spaces and (<i>N</i>+ 1)-Webs
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作者 V. S. Bolodurin 《Applied Mathematics》 2013年第11期14-22,共9页
For a correspondence in question we establish a sequence of fundamental geometrical objects of the correspondence and find invariant normalizations of the first and second orders of all hupersurfaces under the corresp... For a correspondence in question we establish a sequence of fundamental geometrical objects of the correspondence and find invariant normalizations of the first and second orders of all hupersurfaces under the correspondence. We single out main tensors of the correspondence and establish a connection between the geometry of point correspondences between n + 1 hypersurfaces of projective spaces and the theory of multidimensional (n + 1)-webs. 展开更多
关键词 Hupersurface point CORRESPOnDEnCE Invariant normalization Multidimensional (n + 1)-Webs
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L_p(1≤p≤∞) APPROXIMATION BY AN n-DIMENSIONAL SUBSPACE ON A SET OF n+1 POINTS
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作者 史应光 《Acta Mathematica Scientia》 SCIE CSCD 1993年第4期430-436,共7页
Some new characterizations and immediate explicit expressions of best L(1≤p≤∞) approximation and their deviations by an n-dimensional subspace on a set of n+1 points are given.
关键词 APPROXIMATIOn BY An n-DIMEnSIOnAL SUBSPACE On A SET OF n+1 pointS L_p ID Case
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ON THE EXISTENCE OF INFINITELY MANY CRITICAL POINTS OF THE EVEN FUNCTIONAL integral from n=Q to (F(x,u,Du))+integral from n=■Q to (G(x,u))
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作者 严树森 《Acta Mathematica Scientia》 SCIE CSCD 1989年第2期231-240,共10页
In this paper we deal with the existence of infinitely many critical points of the even functional I(u)=integral from n=Q to (F(x,u,Du))+integral from n=(?)Q to (G(x,u)), u∈W^(1,p)(Ω),where G(x, u)=integral from n=o... In this paper we deal with the existence of infinitely many critical points of the even functional I(u)=integral from n=Q to (F(x,u,Du))+integral from n=(?)Q to (G(x,u)), u∈W^(1,p)(Ω),where G(x, u)=integral from n=o to u (g(x,t)dt), under the weak structure conditions on F(x, u, q) by the Mountain Pass Lemma. 展开更多
关键词 On THE EXISTEnCE OF InFInITELY MAnY CRITICAL pointS OF THE EVEn FUnCTIOnAL integral from n=Q to x u Du On THE EXISTEnCE OF InFInITELY MAnY CRITICAL pointS OF THE EVEn FUnCTIOnAL integral from n Q to x u
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Singularities of the Moduli Space of n Unordered Points on the Riemann Sphere
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作者 WU Yue XU Bin 《Chinese Quarterly Journal of Mathematics》 2020年第2期145-162,共18页
We classify the nite groups associated to the orbifold singularities of the moduli space of n≥5 unordered points on the Riemann sphere.
关键词 STABILIZER Orbifold singularity Unordered n point Riemann sphere
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Transmission System Reconfiguration to Reduce Losses and Cost Ensuring Voltage Security
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作者 Veerapandiyan V. Mary D. 《Journal of Power and Energy Engineering》 2016年第6期4-12,共9页
The aim of this paper is to reduce the losses, total generation cost by switching of transmission line and to maintain voltage security under N - 1 contingency conditions. Generation cost is calculated and the pr... The aim of this paper is to reduce the losses, total generation cost by switching of transmission line and to maintain voltage security under N - 1 contingency conditions. Generation cost is calculated and the priority list is made for switching the line. The problem is solved by ACOPF using Interior Point Method. In order to test the feasibility and effectiveness of the above method, a sample 6-bus system and IEEE 30-bus system have been used. The impact of switching on system parameter includes the generation cost, locational marginal pricing (LMP) and transmission losses, ensuring voltage security of the system. 展开更多
关键词 Transmission Switching (TS) AC Optimal Power Flow (ACOPF) n - 1 Contingency and Interior point Method
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Study of Fixed Point Theorems for Higher Dimension in Partially Ordered Metric Spaces
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作者 Ibtisam Masmali Sumitra Dalal 《Applied Mathematics》 2016年第5期399-412,共14页
In this paper, we establish the existence and uniqueness of fixed points of operator , when n is an arbitrary positive integer and X is a partially ordered complete metric space. We have shown examples to verify our w... In this paper, we establish the existence and uniqueness of fixed points of operator , when n is an arbitrary positive integer and X is a partially ordered complete metric space. We have shown examples to verify our work. Our results generalize the recent fixed point theorems cited in [1]-[4] etc. and include several recent developments. 展开更多
关键词 n-Tupled Coincidence points n-Tupled Coincidence Fixed points Compatible Maps Fixed points and Partially Ordered Metric Spaces
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<i>N</i>-Order Fixed Point Theory for N-Order Generalized Meir-Keeler Type Contraction in Partially Ordered Metric Spaces
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作者 Shiyun Wang Jingwen Zhang 《Journal of Applied Mathematics and Physics》 2019年第5期1174-1184,共11页
This paper concerns N-order fixed point theory in partially ordered metric spaces. For the sake of simplicity, we start our investigations with the tripled case. We define tripled generalized Meir-Keeler type contract... This paper concerns N-order fixed point theory in partially ordered metric spaces. For the sake of simplicity, we start our investigations with the tripled case. We define tripled generalized Meir-Keeler type contraction which extends the definition of [Bessem Samet, Coupled fixed point theorems for a generalized Meir-Keeler contraction in partially ordered metric spaces, Nonlinear Anal. 72 (2010), 4508-4517]. We then discuss the existence and uniqueness of tripled fixed point theorems in partially ordered metric spaces. For general cases, we generalized our results to the N-order case. The results will promote the study of N-order fixed point theory. 展开更多
关键词 Tripled Fixed point Meir-Keeler TYPE COnTRACTIOn PARTIALLY Ordered Set n-Order Fixed point
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Preliminary Exploration on Properties of the Equidistant Conjugate Points of Higher Dimensional Simplex
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作者 ZENG Jian-guo 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第1期77-81,共5页
In this paper, the concept of the equidistant conjugate points of a triangle to the n-dimensional Euclidean space is extended. The concept of equidistant conjugate point in high dimensional simplex is defined, and the... In this paper, the concept of the equidistant conjugate points of a triangle to the n-dimensional Euclidean space is extended. The concept of equidistant conjugate point in high dimensional simplex is defined, and the property of the equidistant conjugate points of a triangle is generalized to high dimensional simplex. 展开更多
关键词 SIMPLEX equidistant conjugate point n-dimensional Euclidean space kdimensional spatial (k+1)-polygon
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A General Method of Researching the N-Ordered Fixed Point on a Metric Space with a Graph
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作者 Xiaonan Liang Shiyun Wang 《Journal of Applied Mathematics and Physics》 2020年第12期2846-2860,共15页
In this paper, we propose a new perspective to discuss the N-order fixed point theory of set-valued and single-valued mappings. There are two aspects in our work: we first define a product metric space with a graph fo... In this paper, we propose a new perspective to discuss the N-order fixed point theory of set-valued and single-valued mappings. There are two aspects in our work: we first define a product metric space with a graph for the single-valued mapping whose conversion makes the results and proofs concise and straightforward, and then we propose an <em>SG</em>-contraction definition for set-valued mapping which is more general than some recent contraction’s definition. The results obtained in this paper extend and unify some recent results of other authors. Our method to discuss the N-order fixed point unifies <em>N</em>-order fixed point theory of set-valued and single-valued mappings. 展开更多
关键词 n-Order Fixed point Product Metric Space Endowed with a Graph Set-Valued Mapping SG-Contraction
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于桥水库流域地表水非点源N时空变化特征 被引量:34
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作者 李俊然 陈利顶 +2 位作者 傅伯杰 张淑荣 李广清 《地理科学》 CSCD 北大核心 2002年第2期238-242,共5页
在野外水样监测 (1999年 5月~ 2 0 0 0年 10月 )和土地利用调查的基础上 ,利用遥感影像和数字化地形图 ,运用GIS的空间分析和图形叠置功能 ,研究于桥水库流域地表水非点源N的时空变化特征。结果表明 ,在时间上 ,NH+ 4 -N的峰值出现在... 在野外水样监测 (1999年 5月~ 2 0 0 0年 10月 )和土地利用调查的基础上 ,利用遥感影像和数字化地形图 ,运用GIS的空间分析和图形叠置功能 ,研究于桥水库流域地表水非点源N的时空变化特征。结果表明 ,在时间上 ,NH+ 4 -N的峰值出现在枯水期 ,而NO-3 -N的峰值出现在丰水期 ;在空间上 ,NH+ 4 -N含量在中部平原区最高 ,南部丘陵和北部山区居其次 ,NO-3 -N含量的变化则不具有明显的规律性。NH+ 4 -N和NO-3 -N不同的时空分布特征与它们的化学性质及流域内土地利用格局有关。 展开更多
关键词 于桥水库流域 非点源 土地利用 GIS 地理信息系统 生态系统
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折点氯化法处理高NH_3-N含钴废水试验与工程实践 被引量:40
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作者 宋卫锋 骆定法 +3 位作者 王孝武 陈嘉嘉 黄子安 黎伟海 《环境工程》 CAS CSCD 北大核心 2006年第5期12-13,共2页
高NH3-N化学冶金废水是一种难处理废水。针对该类废水NH3-N高,含盐量高,难以生化处理的特征,首先对应用折点氯化法处理该类废水进行了实验室小试研究,根据试验结果进行了工程实践,出水达到了国家二级标准要求,并对工程实践中需注意的问... 高NH3-N化学冶金废水是一种难处理废水。针对该类废水NH3-N高,含盐量高,难以生化处理的特征,首先对应用折点氯化法处理该类废水进行了实验室小试研究,根据试验结果进行了工程实践,出水达到了国家二级标准要求,并对工程实践中需注意的问题进行了总结。 展开更多
关键词 折点氯化 nH3-n 废水 试验研究 工程实践
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NIPA/DMAA共聚物及其水溶液相转变温度的研究 被引量:11
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作者 曾钫 刘新星 童真 《高分子材料科学与工程》 EI CAS CSCD 北大核心 1997年第5期100-103,共4页
合成了不同配比的N-异丙基丙烯酰胺(NIPA)/N,N-二甲基丙烯酰胺(DMAA)共聚物并用红外光谱对它们进行了验证。DSC分析表明,共聚物的Tg随NIPA含量逐渐增大先是显著升高,当NIPA含量为46.5mol%时... 合成了不同配比的N-异丙基丙烯酰胺(NIPA)/N,N-二甲基丙烯酰胺(DMAA)共聚物并用红外光谱对它们进行了验证。DSC分析表明,共聚物的Tg随NIPA含量逐渐增大先是显著升高,当NIPA含量为46.5mol%时,Tg达132℃,随后共聚物的Tg仅有微小的升高。共聚物水溶液的相转变温度比PNIPA均聚物高,当NIPA的含量为46.5mol%时,共聚物的雾点温度高达51.6℃,我们认为这是因为共聚物分子链的疏水性较PNIPA均聚物分子链的低所致。 展开更多
关键词 异丙基 相变 聚丙烯酰胺 共聚物 甲基丙烯酰胺
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肥液浓度对单膜孔入渗NO_3^--N运移特性影响的室内试验研究 被引量:25
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作者 董玉云 费良军 穆红文 《农业工程学报》 EI CAS CSCD 北大核心 2006年第5期204-206,共3页
该文通过室内入渗试验,研究了不同浓度的单膜孔肥液入渗NO3--N的分布特性。研究表明:不同浓度的膜孔肥液入渗土壤NO3--N浓度的湿润锋运移距离与土壤水分运动的湿润锋一致;肥液浓度越大,相同入渗时间的NO3--N浓度锋运移距离越大,土壤剖面... 该文通过室内入渗试验,研究了不同浓度的单膜孔肥液入渗NO3--N的分布特性。研究表明:不同浓度的膜孔肥液入渗土壤NO3--N浓度的湿润锋运移距离与土壤水分运动的湿润锋一致;肥液浓度越大,相同入渗时间的NO3--N浓度锋运移距离越大,土壤剖面NO3--N浓度最大值越大,相同深度处土壤NO3--N浓度也越大。肥液入渗土壤NO3--N浓度分布特征与湿润体深度符合分段函数模型。供水入渗过程中,NO3--N浓度锋运移距离和浓度最大值均随时间的延长而增大;再分布过程中,NO3--N浓度锋运移距离继续增大,而NO3--N浓度最大值逐渐减小。 展开更多
关键词 膜孔灌 点源入渗 肥液浓度 nO3^--n浓度分布
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