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The response of roots and the rhizosphere environment to integrative cultivation practices in paddy rice
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作者 Hanzhu Gu Xian Wang +10 位作者 Minhao Zhang Wenjiang Jing Hao Wu Zhilin Xiao Weiyang Zhang Junfei Gu Lijun Liu Zhiqin Wang Jianhua Zhang Jianchang Yang Hao Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第6期1879-1896,共18页
Integrative cultivation practices(ICPs)are essential for enhancing cereal yield and resource use efficiency.However,the effects of ICP on the rhizosphere environment and roots of paddy rice are still poorly understood... Integrative cultivation practices(ICPs)are essential for enhancing cereal yield and resource use efficiency.However,the effects of ICP on the rhizosphere environment and roots of paddy rice are still poorly understood.In this study,four rice varieties were produced in the field.Each variety was treated with six different cultivation techniques,including zero nitrogen application(0 N),local farmers’practice(LFP),nitrogen reduction(NR),and three progressive ICP techniques comprised of enhanced fertilizer N practice and increased plant density(ICP1),a treatment similar to ICP1 but with alternate wetting and moderate drying instead of continuous flooding(ICP2),and the same practices as ICP2 with the application of organic fertilizer(ICP3).The ICPs had greater grain production and nitrogen use efficiency than the other three methods.Root length,dry weight,root diameter,activity of root oxidation,root bleeding rate,zeatin and zeatin riboside compositions,and total organic acids in root exudates were elevated with the introduction of the successive cultivation practices.ICPs enhanced nitrate nitrogen,the activities of urease and invertase,and the diversity of microbes(bacteria)in rhizosphere and non-rhizosphere soil,while reducing the ammonium nitrogen content.The nutrient contents(ammonium nitrogen,total nitrogen,total potassium,total phosphorus,nitrate,and available phosphorus)and urease activity in rhizosphere soil were reduced in all treatments in comparison with the non-rhizosphere soil,but the invertase activity and bacterial diversity were greater.The main root morphology and physiology,and the ammonium nitrogen contents in rhizosphere soil at the primary stages were closely correlated with grain yield and internal nitrogen use efficiency.These findings suggest that the coordinated enhancement of the root system and the environment of the rhizosphere under integrative cultivation approaches may lead to higher rice production. 展开更多
关键词 rice(Oryza sativa l.) nitrogen use efficiency grain yield integrative cultivation practices ROOTS
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ON PARAMETRIC MARCINKIEWICZ INTEGRALS RELATED TO BLOCK SPACES 被引量:1
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作者 WuHuoxiong ZhangPu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第3期258-266,共9页
In this paper,the L2-boundedness of a class of parametric Marcinkiewicz integral μρ Ω,h with kernel function Ω in B 0,0 q(S n-1) for some q>1,and the radial function h(x)∈l∞(Ls)(R +) for 1<s≤∞ are... In this paper,the L2-boundedness of a class of parametric Marcinkiewicz integral μρ Ω,h with kernel function Ω in B 0,0 q(S n-1) for some q>1,and the radial function h(x)∈l∞(Ls)(R +) for 1<s≤∞ are given.The Lp(Rn)(2≤p<∞) boundedness of μ *,ρ Ω,h,λ and μ ρ Ω,h,S with Ω in B 0,0 q(S n-1) and h(|x|)∈l∞(Ls)(R +) in application are obtained.Here μ *,ρ Ω,h,λ and μ ρ Ω,h,S are parametric Marcinkiewicz integrals corresponding to the Littlewood-Paley g* λ function and the Lusin area function S,respectively. 展开更多
关键词 Marcinkiewicz integral littlewood-Paley g-function lusin area integral block space l∞(ls)(R %PlUS%)
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Path integral solutions for n-dimensional stochastic differential equations underα-stable Lévy excitation
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作者 Wanrong Zan Yong Xu Jürgen Kurths 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2023年第2期98-112,共15页
In this paper,the path integral solutions for a general n-dimensional stochastic differential equa-tions(SDEs)withα-stable Lévy noise are derived and verified.Firstly,the governing equations for the solutions of... In this paper,the path integral solutions for a general n-dimensional stochastic differential equa-tions(SDEs)withα-stable Lévy noise are derived and verified.Firstly,the governing equations for the solutions of n-dimensional SDEs under the excitation ofα-stable Lévy noise are obtained through the characteristic function of stochastic processes.Then,the short-time transition probability density func-tion of the path integral solution is derived based on the Chapman-Kolmogorov-Smoluchowski(CKS)equation and the characteristic function,and its correctness is demonstrated by proving that it satis-fies the governing equation of the solution of the SDE,which is also called the Fokker-Planck-Kolmogorov equation.Besides,illustrative examples are numerically considered for highlighting the feasibility of the proposed path integral method,and the pertinent Monte Carlo solution is also calculated to show its correctness and effectiveness. 展开更多
关键词 Path integral method α-stable vy noise Monte carlo method Fokker-Planck-Kolmogorov equation
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LÉVY AREA ANALYSIS AND PARAMETER ESTIMATION FOR FOU PROCESSES VIA NON-GEOMETRIC ROUGH PATH THEORY
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作者 Zhongmin QIAN Xingcheng XU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1609-1638,共30页
This paper addresses the estimation problem of an unknown drift parameter matrix for a fractional Ornstein-Uhlenbeck process in a multi-dimensional setting.To tackle this problem,we propose a novel approach based on r... This paper addresses the estimation problem of an unknown drift parameter matrix for a fractional Ornstein-Uhlenbeck process in a multi-dimensional setting.To tackle this problem,we propose a novel approach based on rough path theory that allows us to construct pathwise rough path estimators from both continuous and discrete observations of a single path.Our approach is particularly suitable for high-frequency data.To formulate the parameter estimators,we introduce a theory of pathwise Itôintegrals with respect to fractional Brownian motion.By establishing the regularity of fractional Ornstein-Uhlenbeck processes and analyzing the long-term behavior of the associated Lévy area processes,we demonstrate that our estimators are strongly consistent and pathwise stable.Our findings offer a new perspective on estimating the drift parameter matrix for fractional Ornstein-Uhlenbeck processes in multi-dimensional settings,and may have practical implications for fields including finance,economics,and engineering. 展开更多
关键词 Itôintegration vy area non-geometric rough path fOU processes pathwise stability long time asymptotic high-frequency data
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Endpoint Estimates for Commutators of Fractional Integrals Associated to Operators with Heat Kernel Bounds
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作者 Liu Xian-jun Li Wen-ming Yan Xue-fang 《Communications in Mathematical Research》 CSCD 2017年第1期73-84,共12页
Let L be the infinitesimal generator of an analytic semigroup on L;(R;)with pointwise upper bounds on heat kernel,and denote by L;the fractional integrals of L.For a BMO function b(x),we show a weak type Llog L es... Let L be the infinitesimal generator of an analytic semigroup on L;(R;)with pointwise upper bounds on heat kernel,and denote by L;the fractional integrals of L.For a BMO function b(x),we show a weak type Llog L estimate of the commutators [b,L;](f)(x) = b(x)L;(f)(x)-L;(bf)(x).We give applications to large classes of differential operators such as the Schr¨odinger operators and second-order elliptic operators of divergence form. 展开更多
关键词 fractional integral COMMUTATOR llog l estimate SEMIGROUP sharp maximal function
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Hypersingular parameterized Marcinkiewicz integrals with variable kernels on Sobolev and Hardy-Sobolev spaces 被引量:2
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作者 CHEN Jie-cheng YU Xiao ZHANG Yan-dan WANG Hui 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2008年第4期420-430,共11页
Let α≥ 0 and 0 〈 ρ ≤ n/2, the boundedness of hypersingular parameterized Marcinkiewicz integrals μΩ,α^ρ with variable kernels on Sobolev spaces Lα^ρ and HardySobolev spaces Hα^ρ is established.
关键词 parameterized Marcinkiewicz integral variable kernel Hardy-Sobolev space l^α-Dini condition
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Orliczφ-弦对数Minkowski不等式
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作者 赵长健 《数学年刊(A辑)》 CSCD 北大核心 2024年第1期15-24,共10页
本文通过引进新的混合弦测度和Orlicz混合弦测度概念,并且利用新近建立的Orlicz弦Minkowski不等式,建立了Orlicz空间上的混合弦积分的φ-弦对数Minkowski不等式.我们的结果φ-弦对数Minkowski不等式,在两种特殊情况下分别产生了弦对数Mi... 本文通过引进新的混合弦测度和Orlicz混合弦测度概念,并且利用新近建立的Orlicz弦Minkowski不等式,建立了Orlicz空间上的混合弦积分的φ-弦对数Minkowski不等式.我们的结果φ-弦对数Minkowski不等式,在两种特殊情况下分别产生了弦对数Minkowski不等式和L_(p)-弦对数Minkowski不等式. 展开更多
关键词 混合弦积分 l_(p)-混合弦积分 Orlicz混合弦积分 对数Minkowski不等式 弦对数Minkowski不等式
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Multilinear singular and fractional integrals on weighted Hardy spaces
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作者 ZHANG Pu LAN Jia-cheng 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第2期214-220,共7页
In this paper the boundedness properties of multilinear singular and fractional integrals on the weighted Hardy spaces are studied.
关键词 multilinear singular integral multilinear fractional integral lipschitz function l^r-Dini condition weighted Hardy space
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L2 Syntactic Alignment in the Reading-Writing Integrated Continuation Task: Evidence From Chinese EFL Learners’ Description of Motion Events 被引量:7
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作者 Min WANG Qiao GAN Julie BOLAND 《Chinese Journal of Applied Linguistics》 2021年第3期292-313,430,共23页
This study investigated how the mode in which the reading-writing integrated continuation task was conducted modulates the effects of second language(L2) syntactic alignment, through the English motion event construct... This study investigated how the mode in which the reading-writing integrated continuation task was conducted modulates the effects of second language(L2) syntactic alignment, through the English motion event construction with manner verbs. Ninety Chinese students were assigned to either of the two experimental groups or a control group, and they all experienced a pretest, an alignment phase and a posttest. In the alignment phase, the two experimental groups completed a reading-writing integrated continuation task but in different modes. For the multi-turn mode,participants reconstructed a picture story by continuing the episodes extracted from the story with one episode presented and continued at a time;for the single-turn mode, the first half of the same picture story was presented as a chunk, and then participants read and continued it. Results show that L2 learners aligned with the target structure in completing the story, and the alignment effect was retained in the posttest conducted after a delay of two weeks. Moreover, syntactic alignment was modulated by task mode with the multi-turn group exhibiting stronger immediate and longterm alignment effects. We conclude that the continuation task is a fruitful context for L2 structural alignment, and the magnitude of alignment effect hinges on interactive intensity. 展开更多
关键词 reading-writing integrated continuation task syntactic alignment task mode interactive intensity motion event construction with manner verbs l2 learning
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An Integrated Genetic,Physical and Transcript Map of Homoeologous Chromosomes 12 and 26 in Upland Cotton(Gossypium hirsutum L.) 被引量:2
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作者 KOHEL Russell J CHO Jaemin TOMKINS Jeffrey YU John Z 《棉花学报》 CSCD 北大核心 2008年第S1期22-,共1页
While Upland cotton(Gossypium hirsutum L.) represents 95% of the world production,its genetic improvement is hindered by the shortage of effective genomic tools and resources.The
关键词 An integrated Genetic Physical and Transcript Map of Homoeologous Chromosomes 12 and 26 in Upland Cotton Gossypium hirsutum l
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一类广义积分integral from n=0 to ∞(((sin(θ_x))/x)~ndx)的计算
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作者 赵剑威 吴志勤 雒秋明 《大学数学》 北大核心 2005年第1期126-129,共4页
利用三角函数幂公式、L′Hospital法则、分部积分公式,得到含有三角函数的第一类广义积分integral from n=0 to ∞(((sin(θ_x))/x)~ndx)的计算公式,其中n≥1且θ≠0.
关键词 广义积分 三角函数幂公式 ′Hospital法则 分部积分 数学归纳法
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Occurrence Reasons and Integrated Control of Physiological Chlorosis ofCinnamomum camphora L. in Urban Area of Pingdingshan City
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作者 Li Shihong 《Plant Diseases and Pests》 CAS 2014年第1期9-12,16,共5页
The relevant factors for physiological chlorosis of Cinnamomum camphora L. in Pingdingshan were studied combining with references and production sur- vey. The resuhs showed that the disease was the integrated results ... The relevant factors for physiological chlorosis of Cinnamomum camphora L. in Pingdingshan were studied combining with references and production sur- vey. The resuhs showed that the disease was the integrated results of soil environment, planting situation, microenvironment construction and maintenance manage- ment. Therefore, the countermeasures of "prevention first, restore tree vigor; integrated control, enhance tree vigor" were proposed. Chlorosis of C. camphora had been basically controlled after four years, and the control effect was obvious. 展开更多
关键词 Cinnamomum camphora l. Physiological chlorosis Occurrence reasons integrated control
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AREA INTEGRAL FUNCTIONS FOR SECTORIAL OPERATORS ON L^p SPACES 被引量:1
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作者 陈泽乾 孙牧 《Acta Mathematica Scientia》 SCIE CSCD 2014年第3期739-747,共9页
Area integral functions are introduced for sectorial operators on L^p-spaces. We establish the equivalence between the square and area integral functions for sectorial operators on L^p spaces. This follows that the re... Area integral functions are introduced for sectorial operators on L^p-spaces. We establish the equivalence between the square and area integral functions for sectorial operators on L^p spaces. This follows that the results of Cowling, Doust, McIntosh, Yagi, and Le Merdy on H^∞ functional calculus of seetorial operators on LP-spaces hold true when the square functions are replaced by the area integral functions. 展开更多
关键词 Sectorial operator H^∞ Functional calculus area integral function square function l^p space
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SOME BOUNDED RESULTS OF θ(t)-TYPE SINGULAR INTEGRAL OPERATORS
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作者 赵凯 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第5期573-578,共6页
Let B be a Banach space in UMD with an unconditional basis. The boundedness of the θ (t)_type singular integral operators in L p B(R n),(1≤p<+∞) and H 1 B(R n) spaces are discussed.
关键词 θ(t) _type singular integral operators l p B(R n) space H 1 B(R n) space
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Unified treatment of the bound states of the Schioberg and the Eckart potentials using Feynman path integral approach
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作者 A.Diaf 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第2期39-45,共7页
We obtain analytical expressions for the energy eigenvalues of both the Schioberg and Eckart potentials using an approximation of the centrifugal term. In order to determine the l-states solutions, we use the Feynman ... We obtain analytical expressions for the energy eigenvalues of both the Schioberg and Eckart potentials using an approximation of the centrifugal term. In order to determine the l-states solutions, we use the Feynman path integral approach to quantum mechanics. We show that by performing nonlinear space-time transformations in the radial path integral, we can derive a transformation formula that relates the original path integral to the Green function of a new quantum solvable system. The explicit expression of bound state energy is obtained and the associated eigenfunctions are given in terms of hypergeometric functions. We show that the Eckart potential can be derived from the Schioberg potential. The obtained results are compared to those produced by other methods and are found to be consistent. 展开更多
关键词 path integrals l-states Schioberg potential Eckart potential
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L^p integrability of trigonometric series with special varying coefficients
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作者 WEI Bao-rong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第4期402-410,共9页
Very recently, Yu, Le and Zhou introduced the so called △B1^* and △B2^* conditions, which are generalizations of the monotone condition. By applying these two new conditions, the author essentially generalizes the... Very recently, Yu, Le and Zhou introduced the so called △B1^* and △B2^* conditions, which are generalizations of the monotone condition. By applying these two new conditions, the author essentially generalizes the classical results of Chen on the necessary and sufficient conditions of the Lp integrability of trigonometric series. In fact, the present paper gives the first result on the necessary and sufficient conditions of the Lp integrability of trigonometric series, where coefficients may have different signs. 展开更多
关键词 l^p integrability trigonometric series special varying coefficients
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On the Fractional Derivatives with an Exponential Kernel
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作者 Enyu Fan Jingshu Wu Shaoying Zeng 《Communications on Applied Mathematics and Computation》 EI 2023年第4期1655-1673,共19页
The present article mainly focuses on the fractional derivatives with an exponential kernel(“exponential fractional derivatives”for brevity).First,several extended integral transforms of the exponential fractional d... The present article mainly focuses on the fractional derivatives with an exponential kernel(“exponential fractional derivatives”for brevity).First,several extended integral transforms of the exponential fractional derivatives are proposed,including the Fourier transform and the Laplace transform.Then,the L2 discretisation for the exponential Caputo derivative with a∈(1,2)is established.The estimation of the truncation error and the properties of the coefficients are discussed.In addition,a numerical example is given to verify the correctness of the derived L2 discrete formula. 展开更多
关键词 Exponential fractional derivative integral transform l2 discretisation Truncation error
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BOUNDEDNESS OF MARCINKIEWICZ INTEGRAL ON THE WEIGHTED HERZ-TYPE HARDY SPACES
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作者 Lejin Xu 《Analysis in Theory and Applications》 2006年第1期56-64,共9页
In this paper, we discuss the boundedness of Marcinkiewicz integral μΩ with homogeneous kernel on the weighted Herz-type Hardy spaces, and prove that μΩ is bounded from HKq^a、P(ω1;ω2) into Kq^a、p (ω1; ω2).
关键词 Marcinkiewicz integral l^r-Dini condition weighted Herz-type Hardy spaces
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A BMO ESTIMATE FOR THE MULTILINEAR SINGULAR INTEGRAL OPERATOR
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作者 Qihui Zhang 《Analysis in Theory and Applications》 2006年第3期271-282,共12页
The behavior on the space L^∞(R^n) for the multilinear singular integral operator defined by TAf(x)=∫RnΩ(x-y)/|x-y|^n+1(A(x)-A(y)△A(y)(x-y))f(y)dy is considered, where 12 is homogeneous of deg... The behavior on the space L^∞(R^n) for the multilinear singular integral operator defined by TAf(x)=∫RnΩ(x-y)/|x-y|^n+1(A(x)-A(y)△A(y)(x-y))f(y)dy is considered, where 12 is homogeneous of degree zero, integrable on the unit sphere and has vanishing is considered, where Ω is homogeneous of degree zero, integrable on the unit sphere and has vanishingmoment of order one, A has derivatives of order one in BMO(R^n). It is proved that if Ω satisfies some minimum size condition and an L1-Dini type regularity condition, then for f ∈ L^∞(R^n), TAf is either infinite almost everywhere or finite almost everywhere, and in the latter case, TAf ∈ BMO(R^n). 展开更多
关键词 multilinear singular integral operator l^1-Dini type regularity condition
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An Accurate Numerical Integrator for the Solution of Black Scholes Financial Model Equation
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作者 Iyakino P. Akpan Johnson O. Fatokun 《American Journal of Computational Mathematics》 2015年第3期283-290,共8页
In this paper the Black Scholes differential equation is transformed into a parabolic heat equation by appropriate change in variables. The transformed equation is semi-discretized by the Method of Lines (MOL). The ev... In this paper the Black Scholes differential equation is transformed into a parabolic heat equation by appropriate change in variables. The transformed equation is semi-discretized by the Method of Lines (MOL). The evolving system of ordinary differential equations (ODEs) is integrated numerically by an L-stable trapezoidal-like integrator. Results show accuracy of relative maximum error of order 10–10. 展开更多
关键词 BlACK Scholes EQUATION Partial Differential Equations (PDEs) Method of lines (MOl) l-Stable Trapezoidal-like integrATOR
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