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Potential Applications of Milk Fractions and Valorization of Dairy By-Products: A Review of the State-of-the-Art Available Data, Outlining the Innovation Potential from a Bigger Data Standpoint 被引量:3
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作者 Serge Rebouillat Salvadora Ortega-Requena 《Journal of Biomaterials and Nanobiotechnology》 2015年第3期176-203,共28页
The unique composition of milk makes this basic foodstuff into an exceptional raw material for the production of new ingredients with desired properties and diverse applications in the food industry. The fractionation... The unique composition of milk makes this basic foodstuff into an exceptional raw material for the production of new ingredients with desired properties and diverse applications in the food industry. The fractionation of milk is the key in the development of those ingredients and products;hence continuous research and development on this field, especially various levels of fractionation and separation by filtration, have been carried out. This review focuses on the production of milk fractions as well as their particular properties, applications and processes that increase their exploitation. Whey proteins and caseins from the protein fraction are excellent emulsifiers and protein supplements. Besides, they can be chemically or enzymatically modified to obtain bioactive peptides with numerous functional and nutritional properties. In this context, valorization techniques of cheese-whey proteins, by-product of dairy industry that constitutes both economic and environmental problems, are being developed. Phospholipids from the milk fat fraction are powerful emulsifiers and also have exclusive nutraceutical properties. In addition, enzyme modification of milk phospholipids makes it possible to tailor emulsifiers with particular properties. However, several aspects remain to be overcome;those refer to a deeper understanding of the healthy, functional and nutritional properties of these new ingredients that might be barriers for its use and acceptability. Additionally, in this review, alternative applications of milk constituents in the non-food area such as in the manufacture of plastic materials and textile fibers are also introduced. The unmet needs, the cross-fertilization in between various protein domains,the carbon footprint requirements, the environmental necessities, the health and wellness new demand, etc., are dominant factors in the search for innovation approaches;these factors are also outlining the further innovation potential deriving from those “apparent” constrains obliging science and technology to take them into account. 展开更多
关键词 MILK Product MILK fractionation Casein Phospholipid WHEY Protein NON-FOOD Application VALORIZATION Enzyme Modification Bioactive Peptides BIGGER DATA Innovation: Closed Open Collaborative Disruptive Inclusive Nested
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Explicit Approximation Solutions and Proof of Convergence of the Space-Time Fractional Advection Dispersion Equations
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作者 E. A. Abdel-Rehim 《Applied Mathematics》 2013年第10期1427-1440,共14页
The space-time fractional advection dispersion equations are linear partial pseudo-differential equations with spatial fractional derivatives in time and in space and are used to model transport at the earth surface. ... The space-time fractional advection dispersion equations are linear partial pseudo-differential equations with spatial fractional derivatives in time and in space and are used to model transport at the earth surface. The time fractional order is denoted by β∈ and ?is devoted to the space fractional order. The time fractional advection dispersion equations describe particle motion with memory in time. Space-fractional advection dispersion equations arise when velocity variations are heavy-tailed and describe particle motion that accounts for variation in the flow field over entire system. In this paper, I focus on finding the precise explicit discrete approximate solutions to these models for some values of ?with ?, ?while the Cauchy case as ?and the classical case as ?with ?are studied separately. I compare the numerical results of these models for different values of ?and ?and for some other related changes. The approximate solutions of these models are also discussed as a random walk with or without a memory depending on the value of . Then I prove that the discrete solution in the Fourierlaplace space of theses models converges in distribution to the Fourier-Laplace transform of the corresponding fractional differential equations for all the fractional values of ?and . 展开更多
关键词 ADVECTION-DISPERSION Processes Grünwald-Letnikov Scheme EXPLICIT Difference Schemes Caputo Time-fractional Derivative Inverse RIESZ Potential Random WALK with and without a Memory CONVERGENCE in Distributions Fourier-Laplace Domain
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Revisiting the Curie-Von Schweidler Law for Dielectric Relaxation and Derivation of Distribution Function for Relaxation Rates as Zipf’s Power Law and Manifestation of Fractional Differential Equation for Capacitor 被引量:1
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作者 Shantanu Das 《Journal of Modern Physics》 2017年第12期1988-2012,共25页
The classical power law relaxation, i.e. relaxation of current with inverse of power of time for a step-voltage excitation to dielectric—as popularly known as Curie-von Schweidler law is empirically derived and is ob... The classical power law relaxation, i.e. relaxation of current with inverse of power of time for a step-voltage excitation to dielectric—as popularly known as Curie-von Schweidler law is empirically derived and is observed in several relaxation experiments on various dielectrics studies since late 19th Century. This relaxation law is also regarded as “universal-law” for dielectric relaxations;and is also termed as power law. This empirical Curie-von Schewidler relaxation law is then used to derive fractional differential equations describing constituent expression for capacitor. In this paper, we give simple mathematical treatment to derive the distribution of relaxation rates of this Curie-von Schweidler law, and show that the relaxation rate follows Zipf’s power law distribution. We also show the method developed here give Zipfian power law distribution for relaxing time constants. Then we will show however mathematically correct this may be, but physical interpretation from the obtained time constants distribution are contradictory to the Zipfian rate relaxation distribution. In this paper, we develop possible explanation that as to why Zipfian distribution of relaxation rates appears for Curie-von Schweidler Law, and relate this law to time variant rate of relaxation. In this paper, we derive appearance of fractional derivative while using Zipfian power law distribution that gives notion of scale dependent relaxation rate function for Curie-von Schweidler relaxation phenomena. This paper gives analytical approach to get insight of a non-Debye relaxation and gives a new treatment to especially much used empirical Curie-von Schweidler (universal) relaxation law. 展开更多
关键词 Power LAW RELAXATION RATE Distribution fractionAL Derivative fractionAL Integration Curie-Von Schweidler LAW Time-Constants Laplace INTEGRAL Zipfs LAW INTEGRAL Representation Time Dependent RELAXATION RATE Scale Dependent RELAXATION RATE Non-Debye RELAXATION
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Higher-Order Duality for Minimax Fractional Type Programming Involving Symmetric Matrices
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作者 Caiyun Jin Cao-Zong Cheng 《Applied Mathematics》 2011年第11期1387-1392,共6页
Convexity and generalized convexity play important roles in optimization theory. With the development of programming problem, there has been a growing interest in the higher-order dual problem and a lot of related gen... Convexity and generalized convexity play important roles in optimization theory. With the development of programming problem, there has been a growing interest in the higher-order dual problem and a lot of related generalized convexities are given. In this paper, we give the convexity of (F, α ,p ,d ,b , φ )β vector-pseudo- quasi-Type I and formulate a higher-order duality for minimax fractional type programming involving symmetric matrices, and give the weak, strong and strict converse duality theorems under the condition of higher-order (F, α ,p ,d ,b , φ )β vector-pseudoquasi-Type I. 展开更多
关键词 HIGHER-ORDER (F α p d b φ )β Vector-Pseudoquasi-Type I HIGHER-ORDER DUALITY MINIMAX fractionAL TYPE PROGRAMMING Positive Semidefinite Symmetric Matrix
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Fractionalization of a Class of Semi-Linear Differential Equations
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作者 Issic K. C. Leung K. Gopalsamy 《Applied Mathematics》 2017年第11期1715-1744,共30页
The dynamics of a fractionalized semi-linear scalar differential equation is considered with a Caputo fractional derivative. By using a symbolic operational method, a fractional order initial value problem is converte... The dynamics of a fractionalized semi-linear scalar differential equation is considered with a Caputo fractional derivative. By using a symbolic operational method, a fractional order initial value problem is converted into an equivalent Volterra integral equation of second kind. A brief discussion is included to show that the fractional order derivatives and integrals incorporate a fading memory (also known as long memory) and that the order of the fractional derivative can be considered to be an index of memory. A variation of constants formula is established for the fractionalized version and it is shown by using the Fourier integral theorem that this formula reduces to that of the integer order differential equation as the fractional order approaches an integer. The global existence of a unique solution and the global Mittag-Leffler stability of an equilibrium are established by exploiting the complete monotonicity of one and two parameter Mittag-Leffler functions. The method and the analysis employed in this article can be used for the study of more general systems of fractional order differential equations. 展开更多
关键词 fractionAL INTEGRAL Caputo fractionAL Derivative Fading Memory Mittag-Leffler Functions Complete MONOTONICITY fractionALIZATION Variation of CONSTANTS Formula Fourier INTEGRAL Theorem Mittag-Leffler Stability
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滇西吉义独蛇绿混杂岩的岩石地球化学特征、成因和构造环境探讨 被引量:2
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作者 何琦 肖龙 +1 位作者 魏启荣 倪平泽 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第12期3229-3240,共12页
滇西吉义独蛇绿混杂岩位于金沙江缝合带的南端,岩石组合出露较齐全,包括堆晶橄榄岩、堆晶辉石岩、堆晶辉长岩以及玄武岩等,它们呈构造岩片的形式产出并与外来岩块组成蛇绿混杂岩。堆晶橄榄岩和辉石岩具低Al_2O_3,低TiO_2,而高Mg~#值(Mg~... 滇西吉义独蛇绿混杂岩位于金沙江缝合带的南端,岩石组合出露较齐全,包括堆晶橄榄岩、堆晶辉石岩、堆晶辉长岩以及玄武岩等,它们呈构造岩片的形式产出并与外来岩块组成蛇绿混杂岩。堆晶橄榄岩和辉石岩具低Al_2O_3,低TiO_2,而高Mg~#值(Mg~#=0.88~0.92),富集Cr和Ni,稀土总量偏低(∑REE=14.82×10^(-6)~27.75×10^(-6)),倒"U"型的稀土元素分布特征。堆晶辉长岩和玄武岩的Mg~#值较低,分别为0.70~0.79和0.51~0.66,具拉斑系列的演化趋势。玄武岩可以细分为2组:第一组玄武岩以平坦型稀土配分模式,低Mg~#(Mg~#=0.44~0.46),低稀土总量(∑REE=52.29×10^(-6)~60.26×10^(-6))为特征;第二组玄武岩则为LREE弱富集型的稀土配分模式,其Mg~#较高(Mg~#=0.54~0.68),稀土总量也较高(ΣREE=62.13×10^(-6)~101.87×10^(-6))。在原始地幔标准化的微量元素配分图解中,两组玄武岩均相对富集大离子亲石元素而亏损Nb、Ta和Ti,与岛弧岩浆岩类似,明显不同于N-MORB。岩石的Sr-Nd同位素组成较为均一和稳定,堆晶橄榄岩和辉石岩的(^(87)Sr/^(86)Sr);=0.7051~0.7056,ε_(Nd)(t)=2.8~4.1,玄武岩的(^(87)Sr/^(86)Sr)_i=0.7050~0.7056,ε_(Nd)(t)=5.1~5.8,且显示出原始地幔的同位素组成特征,暗示这些岩石为同源岩浆分异演化而成的岩浆产物。岩浆演化的主要方式为分离结晶作用,受地壳混染不明显。岩浆结晶形成岩石的顺序为:堆晶橄榄岩→堆晶辉石岩→堆晶辉长岩→玄武岩2组→玄武岩1组。岩石地球化学特征表明,吉义独蛇绿岩的形成与俯冲作用有关,且形成于金沙江洋内俯冲的消减环境。 展开更多
关键词 西 绿 ophiolitic MELANGE geochemical characteristics REE fractional crystallization rare earth elements Jinshajiang suture zone basic unit
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Equilibrium thallium isotope fractionation and its constraint on Earth’s late veneer 被引量:3
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作者 Tong Fang Yun Liu 《Acta Geochimica》 EI CAS CSCD 2019年第4期459-471,共13页
Equilibrium isotope fractionation of thallium(Tl) includes the traditional mass-dependent isotope fractionation effect and the nuclear volume effect(NVE). The NVE dominates the overall isotope fractionation, especiall... Equilibrium isotope fractionation of thallium(Tl) includes the traditional mass-dependent isotope fractionation effect and the nuclear volume effect(NVE). The NVE dominates the overall isotope fractionation, especially at high temperatures. Heavy Tl isotopes tend to be enriched in oxidized Tl^3+-bearing species. Our NVE fractionation results of oxidizing Tl^+ to Tl^3+ can explain the positive enrichments observed in ferromanganese sediments. Experimental results indicate that there could be0.2–0.3 e-unit fractionation between sulfides and silicates at 1650 ℃. It is consistent with our calculation results,which are in the range of 0.17–0.38 e-unit. Importantly,Tl’s concentration in the bulk silicate Earth(BSE) can be used to constrain the amount of materials delivered to Earth during the late veneer accretion stage. Because the Tl concentration in BSE is very low and its Tl isotope composition is similar with that of chondrites, suggesting either no Tl isotope fractionation occurred during numerous evaporation events, or the Tl in current BSE was totally delivered by late veneer. If it is the latter, the Tl-contentbased estimation could challenge the magnitude of late veneer which had been constrained by the amount of highly siderophile elements in BSE. Our results show that the lateaccreted mass is at least five-times larger than the previously suggested magnitude, i.e., 0.5 wt% of current Earth’s mass. The slightly lighter 205 Tl composition of BSE relative to chondrites is probable a sign of occurrence of Tlbearing sulfides, which probably were removed from the mantle in the last accretion stage of the Earth. 展开更多
关键词 EQUILIBRIUM TL isotope fractionation Nuclear volume effect TL fractionations between SILICATES and sulfides LATE VENEER First-principles calculation
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内蒙古中部四子王旗大庙岩体时代及成因 被引量:65
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作者 章永梅 张华锋 +1 位作者 刘文灿 周志广 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第12期3165-3181,共17页
华北北缘的内蒙古中部地区出露大量晚古生代-早中生代花岗岩类,在空间上构成一条巨大的东西向花岗岩带。四子王旗大庙岩体作为一个典型的代表,以花岗闪长岩为主,其内部普遍发育暗色微粒包体(MMEs),是认识花岗岩岩石成因和演化的关键。... 华北北缘的内蒙古中部地区出露大量晚古生代-早中生代花岗岩类,在空间上构成一条巨大的东西向花岗岩带。四子王旗大庙岩体作为一个典型的代表,以花岗闪长岩为主,其内部普遍发育暗色微粒包体(MMEs),是认识花岗岩岩石成因和演化的关键。本文对包体及寄主岩进行了同位素测年、岩相学、矿物化学、全岩主量元素和微量元素分析。寄主岩石中的锆石LA-ICPMS U-Pb年龄平均为265±7Ma(2σ),包体中单颗粒黑云母Rb-Sr年龄为253±5Ma(MSWD=0.85),属晚二叠世-早三叠世岩浆活动的产物。包体具塑性外形及岩浆结构,存在多种不平衡矿物组合;MME中的斜长石An组分及黑云母斑晶中MgO成分呈多期震荡,同时总体上均显示出幔部高于核、边部的特征,暗示斑晶可能为围岩捕虏晶,这种相似的成分变化指示包体与寄主岩相互作用引起的结晶环境改变,标志着岩浆成分的变化,是岩浆混合的标志之一;主量和微量数据进一步证明岩体的岩浆混合成因。Rb/Sr-K/Rb变化关系反映包体非结晶分异或黑云母堆晶的产物,而Ce/Pb-Ce、Ba-δEU和P_2O_5-δEu图及其他微量元素比值图等均表明花岗闪长岩体发生了岩浆混合作用,这也得到岩浆物理化学条件的支持。岩浆底侵和岩浆混合作用是该区岩体形成的主要机制和方式。岩石地球化学特征表明该岩体不同于加厚地壳和俯冲洋壳熔融的TTG和埃达克质岩石,而黑云母矿物化学和岩石地球化学显示其构造背景很可能为同碰撞环境。 展开更多
关键词 magma mixing fractional crystallization LA-ICPMS trace elements mineral Late PALEOZOIC Inner Mongolia genesis Early Mesozoic
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Robust Finite-time Synchronization of Non-identical Fractional-order Hyperchaotic Systems and Its Application in Secure Communication 被引量:5
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作者 Hadi Delavari Milad Mohadeszadeh 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2019年第1期228-235,共8页
This paper proposes a novel adaptive sliding mode control(SMC) method for synchronization of non-identical fractional-order(FO) chaotic and hyper-chaotic systems. Under the existence of system uncertainties and extern... This paper proposes a novel adaptive sliding mode control(SMC) method for synchronization of non-identical fractional-order(FO) chaotic and hyper-chaotic systems. Under the existence of system uncertainties and external disturbances,finite-time synchronization between two FO chaotic and hyperchaotic systems is achieved by introducing a novel adaptive sliding mode controller(ASMC). Here in this paper, a fractional sliding surface is proposed. A stability criterion for FO nonlinear dynamic systems is introduced. Sufficient conditions to guarantee stable synchronization are given in the sense of the Lyapunov stability theorem. To tackle the uncertainties and external disturbances, appropriate adaptation laws are introduced. Particle swarm optimization(PSO) is used for estimating the controller parameters. Finally, finite-time synchronization of the FO chaotic and hyper-chaotic systems is applied to secure communication. 展开更多
关键词 Adaptive SLIDING mode control (ASMC) CHAOS synchronization fractionAL order (FO) hyper-chaotic system LYAPUNOV THEOREM SECURE communication
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Existence of Solutions for Boundary Value Problems of Conformable Fractional Differential Equations
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作者 Xingyue Jian 《Journal of Applied Mathematics and Physics》 2019年第1期233-242,共10页
In this paper, we study a class of boundary value problems for conformable fractional differential equations under a new definition. Firstly, by using the monotone iterative technique and the method of coupled upper a... In this paper, we study a class of boundary value problems for conformable fractional differential equations under a new definition. Firstly, by using the monotone iterative technique and the method of coupled upper and lower solution, the sufficient condition for the existence of the boundary value problem is obtained, and the range of the solution is determined. Then the existence and uniqueness of the solution are proved by the proof by contradiction. Finally, a concrete example is given to illustrate the wide applicability of our main results. 展开更多
关键词 Boundary Value Problems Conformable fractional Differential Equations The Method of COUPLED UPPER and Lower SOLUTION COUPLED SOLUTION MONOTONE ITERATION
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New blind estimation method of evoked potentials based on minimum dispersion criterion and fractional lower order statistics
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作者 Daifeng Zha 《Journal of Biomedical Science and Engineering》 2008年第2期91-97,共7页
Evoked potentials (EPs) have been widely used to quantify neurological system properties. Tra-ditional EP analysis methods are developed under the condition that the background noises in EP are Gaussian distributed. A... Evoked potentials (EPs) have been widely used to quantify neurological system properties. Tra-ditional EP analysis methods are developed under the condition that the background noises in EP are Gaussian distributed. Alpha stable distribution, a generalization of Gaussian, is better for modeling impulsive noises than Gaussian distribution in biomedical signal proc-essing. Conventional blind separation and es-timation method of evoked potentials is based on second order statistics or high order Statis-tics. Conventional blind separation and estima-tion method of evoked potentials is based on second order statistics (SOS). In this paper, we propose a new algorithm based on minimum dispersion criterion and fractional lower order statistics. The simulation experiments show that the proposed new algorithm is more robust than the conventional algorithm. 展开更多
关键词 EVOKED POTENTIALS (EPs) Alpha stable distribution BLIND source separation Minimum dispersion (MD) fractionAL lower order statistics (FLOS)
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Fractional flow reserve: Current applications and overview of the available data 被引量:4
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作者 Matteo Tebaldi Gianluca Campo Simone Biscaglia 《World Journal of Clinical Cases》 SCIE 2015年第8期678-681,共4页
Flow fractional reserve(FFR) allows to evaluate the functional significance of coronary artery lesions, through the ratio of the mean coronary artery pressure after the stenosis to the mean aortic pressure duringmaxim... Flow fractional reserve(FFR) allows to evaluate the functional significance of coronary artery lesions, through the ratio of the mean coronary artery pressure after the stenosis to the mean aortic pressure duringmaximum hyperemia. The actual widely accepted cutoff value is 0.80. Below this value a coronary lesion is considered significant and therefore it requires invasive revascularization. Several studies [in particular Fractional Flow Reserve vs Angiography for Multivessel Evaluation 1(FAME-1) and FAME-2] have shown the relationship between FFR measurement and hard end-points(death, myocardial infarction, and urgent revascularization). Consequently, FFR evaluation represents the cornerstone in the decision-making in intermediate coronary lesions. Recent studies paved the way for further applications of FFR evaluation in complex and tricky clinical settings. In this paper, we perform an overview of the data regarding contemporary application of FFR. In particular, we review the use of FFR in: left main intermediate stenoses, serial stenoses, evaluation after stenting, guidance in coronary artery bypass surgery, and acute coronary syndrome. All the data presented in our overview confirm the essential role of FFR assessment in the daily clinical practice. The shift from "operator-dependent" to "FFR-dependent" evaluation in intermediate coronary artery stenosis is of paramount importance in order to improve the prognosis of our patients, through the discrimination of the functional role of every single coronary stenosis. 展开更多
关键词 Intermediate CORONARY LESION fractional flow RESERVE CORONARY ARTERY BYPASS surgery Left main Acute CORONARY syndrome SERIAL stenoses
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Disturbance Observer Based Speed Control of PMSM Using Fractional Order PI Controller 被引量:6
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作者 Aishwarya Apte Ujjwala Thakar Vrunda Joshi 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2019年第1期316-326,共11页
In this paper, fractional order PI(FOPI) control is developed for speed control of permanent magnet synchronous motor(PMSM). Designing the parameters for FOPI controller is a challenging task, especially for nonlinear... In this paper, fractional order PI(FOPI) control is developed for speed control of permanent magnet synchronous motor(PMSM). Designing the parameters for FOPI controller is a challenging task, especially for nonlinear systems like PMSM.All three PI controllers in the conventional vector controlled speed drive are replaced by FOPI controllers. Design of these FOPI controllers is based on the locally linearized model of PMSM around an operating point. This operating point changes with the load torque. The novelty of the work reported here is in use of Non Linear Disturbance Observer(NLDO) to estimate load torque to obtain this new operating point. All three FOPI controllers are then designed adaptively using this new operating point. The scheme is tested on simulation using MATLAB/SIMULINK and results are presented. 展开更多
关键词 fractionAL order PI (FOPI) non linear DISTURBANCE observer (NLDO) PERMANENT MAGNET SYNCHRONOUS motor(PMSM) vector control
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青藏高原北部新生代走构油茶错、纳丁错火山岩年代学、地球化学特征及其构造意义 被引量:13
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作者 刘建峰 迟效国 +4 位作者 赵秀羽 赵芝 董春艳 黎广荣 赵院东 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第12期3259-3274,共16页
本文对分布于藏北南羌塘地区的走构油茶错和纳丁错新生代火山岩进行了岩石学、同位素年代学和地球化学研究。两个地区火山岩主要由粗面玄武岩、橄榄粗安岩、安粗岩及粗面岩组成,具有从碱性系列火山岩到高钾钙碱性火山岩连续演化的特征... 本文对分布于藏北南羌塘地区的走构油茶错和纳丁错新生代火山岩进行了岩石学、同位素年代学和地球化学研究。两个地区火山岩主要由粗面玄武岩、橄榄粗安岩、安粗岩及粗面岩组成,具有从碱性系列火山岩到高钾钙碱性火山岩连续演化的特征。锆石U-Pb定年表明两个地区火山岩形成时代分别为34.64±0.55Ma和35.03±0.54Ma,另外在走构油茶错安粗岩和粗面岩中发现了大量的捕获锆石。地球化学分析显示,岩石ε_(Hf)(t)均为正值,但随SiO_2含量的增高,ε_(Hf)(t)有减小的趋势。稀土元素配分曲线上轻重稀土分馏明显,无或轻微Eu负异常,尤其是重稀土出现分馏,大多数样品(Sm/Yb)_N值介于6.30~8.25之间,表明原生岩浆起源于含有石榴石的弱亏损型软流圈地幔,中酸性岩浆所具有的类似埃达克岩的地球化学特征是原生幔源岩浆经AFC作用形成的。始新世末期南羌塘地区的火山活动可能与向北俯冲的拉萨地块的岩石圈地幔断离造成的软流圈上涌有关。 展开更多
关键词 Tibetan Plateau northern geochemical characteristics fractional crystallization area Cenozoic VOLCANICS 线 volcanic rocks
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Comparisons of plant calcium fraction between two different vegetation zones in semi-arid region 被引量:2
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作者 MengQi Li XingDong He +2 位作者 XiangXiang Yang YueDan Zhao YuBao Gao 《Research in Cold and Arid Regions》 CSCD 2018年第4期340-346,共7页
To explore the characteristics of plant calcium(Ca) fraction, we analyzed 91 plant species in the Ningxia Habahu National Nature Reserve in Yanchi County of Ningxia and 84 plant species in Zhenglan Banner of Inner Mon... To explore the characteristics of plant calcium(Ca) fraction, we analyzed 91 plant species in the Ningxia Habahu National Nature Reserve in Yanchi County of Ningxia and 84 plant species in Zhenglan Banner of Inner Mongolia. Results show that, for the two regions, there is no significant difference between Ca fraction for the same growth type, and between water soluble Ca content or between hydrochloric acid soluble Ca content for plants of the same ecosystem and between hydrochloric acid soluble Ca content for plants of the same family. In similar vegetation zones, there is a significant difference among hydrochloric acid soluble Ca content for different growth types in Yanchi County and Zhenglan Banner,which was the highest for annual herbs and the lowest for perennial herbs. There is a significant difference between acetic acid soluble Ca content and between hydrochloric acid soluble Ca content for sandy land and grassland ecosystems in Yanchi County. There is a significant difference among the same Ca fraction of different families in the same region. Thus, the characteristics of plant Ca fraction are results of long-term adaptation to the environment. 展开更多
关键词 SEMI-ARID region plant calcium fraction Ningxia Habahu National Nature RESERVE Zhenglan BANNER of Inner Mongolia
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黄土高原地区连续施锌条件下土壤锌的形态及有效性 被引量:39
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作者 魏孝荣 郝明德 张春霞 《中国农业科学》 CAS CSCD 北大核心 2005年第7期1386-1393,共8页
采用连续浸提形态分级方法,研究了连续施用锌肥后锌的土壤化学特性变化。结果表明,经过17年连续施用锌肥,锌在土壤中有明显的累积。0~60cm各土层土壤全锌和有效锌(DTPA-Zn)含量均高于对照,并且表现出锌在表层土壤(0~15cm)累积和向深... 采用连续浸提形态分级方法,研究了连续施用锌肥后锌的土壤化学特性变化。结果表明,经过17年连续施用锌肥,锌在土壤中有明显的累积。0~60cm各土层土壤全锌和有效锌(DTPA-Zn)含量均高于对照,并且表现出锌在表层土壤(0~15cm)累积和向深层土壤迁移的特点。土壤中的锌主要以矿物态锌存在,占土壤全锌含量的95.57%~99.11%。其次为松结态锌,约占全锌的0.82%~3.58%。其它形态锌占全锌的比例很小,不到1.00%。锌肥施入土壤后各形态锌的含量都有较大幅度的增加,施入土壤中的锌有很大一部分转化为矿物态锌,只有一小部分进入土壤溶液,或与有机质、碳酸盐及氧化锰相结合。在土壤各形态锌中,交换态、松结态和碳酸盐态锌均能不同程度反映土壤锌的有效性。长期施用锌肥改善了小麦的锌营养状况,促进了小麦对锌的吸收,施锌小麦各器官锌含量和吸锌量均高于对照。 展开更多
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Existence Theorem for a Nonlinear Functional Integral Equation and an Initial Value Problem of Fractional Order in L<sub>1</sub>(R<sub>+</sub>)
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作者 Ibrahim Abouelfarag Ibrahim Tarek S. Amer Yasser M. Aboessa 《Applied Mathematics》 2013年第2期402-409,共8页
The aim of this paper is to study the existence of integrable solutions of a nonlinear functional integral equation in the space of Lebesgue integrable functions on unbounded interval, L1(R+). As an application we ded... The aim of this paper is to study the existence of integrable solutions of a nonlinear functional integral equation in the space of Lebesgue integrable functions on unbounded interval, L1(R+). As an application we deduce the existence of solution of an initial value problem of fractional order that be studied only on a bounded interval. The main tools used are Schauder fixed point theorem, measure of weak noncompactness, superposition operator and fractional calculus. 展开更多
关键词 NONLINEAR Functional Integral Equation VOLTERRA Operator Measure of Weak Noncompactness fractional Calculus SCHAUDER Fixed Point Theorem
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Mild Solutions for Nonlocal Impulsive Fractional Semilinear Differential Inclusions with Delay in Banach Spaces
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作者 Ahmed Gamal Ibrahim Nawal Abdulwahab Al Sarori 《Applied Mathematics》 2013年第7期40-56,共17页
In this paper, we give various existence results concerning the existence of mild solutions for nonlocal impulsive differential inclusions with delay and of fractional order in Caputo sense in Banach space. We conside... In this paper, we give various existence results concerning the existence of mild solutions for nonlocal impulsive differential inclusions with delay and of fractional order in Caputo sense in Banach space. We consider the case when the values of the orient field are convex as well as nonconvex. Our obtained results improve and generalize many results proved in recent papers. 展开更多
关键词 fractionAL DIFFERENTIAL INCLUSIONS IMPULSIVE SEMILINEAR Functional DIFFERENTIAL INCLUSIONS The Infinitesimal Generator of a Semigroup NONLOCAL Conditions Mild Solutions
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A New Approach for the Exact Solutions of Nonlinear Equations of Fractional Order via Modified Simple Equation Method 被引量:1
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作者 Muhammad Younis 《Applied Mathematics》 2014年第13期1927-1932,共6页
In this article, the modified simple equation method has been extended to celebrate the exact solutions of nonlinear partial time-space differential equations of fractional order. Firstly, the fractional complex trans... In this article, the modified simple equation method has been extended to celebrate the exact solutions of nonlinear partial time-space differential equations of fractional order. Firstly, the fractional complex transformation has been implemented to convert nonlinear partial fractional differential equations into nonlinear ordinary differential equations. Afterwards, modified simple equation method has been implemented, to find the exact solutions of these equations, in the sense of modified Riemann-Liouville derivative. For applications, the exact solutions of time-space fractional derivative Burgers’ equation and time-space fractional derivative foam drainage equation have been discussed. Moreover, it can also be concluded that the proposed method is easy, direct and concise as compared to other existing methods. 展开更多
关键词 Exact Solutions Complex Transformation MODIFIED SIMPLE EQUATION METHOD Nonlinear Equations of fractionAL Order fractionAL Calculus Theory
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新疆哈尔里克山二叠纪碱性花岗岩-石英正长岩组合的成因及其构造意义 被引量:14
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作者 汪传胜 顾连兴 +5 位作者 张遵忠 吴昌志 唐俊华 三金柱 黎广荣 李中华 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第12期3182-3196,共15页
哈尔里克奥姆尔塔格碱性花岗岩(OMAG)侵入于小铺东二长花岗岩中。该岩体岩性较均一,呈灰紫色,主要矿物组合为石英、钾长石、钠长石、碱性角闪石和霓石;化学成分上富硅、碱,贫钙、镁,低铝;富Rb、Th、U和Zr,Ga/Al比值大(3.18×10~4~3... 哈尔里克奥姆尔塔格碱性花岗岩(OMAG)侵入于小铺东二长花岗岩中。该岩体岩性较均一,呈灰紫色,主要矿物组合为石英、钾长石、钠长石、碱性角闪石和霓石;化学成分上富硅、碱,贫钙、镁,低铝;富Rb、Th、U和Zr,Ga/Al比值大(3.18×10~4~3.56×10~4),贫Ba、Sr,岩石中Co、Cr、V和Ni等过渡元素显著亏损,U、Hf、Zr和Nb等高场强元素的含量高;稀土总量较高,配分模式右倾,并具有显著的负铕异常;LA-ICP-MS锆石^(206)Pb/^(238)U加权平均年龄为287.6±2.1Ma;具有正的ε_(Nd)(t)值(+4.96),较低的(^(87)Sr/^(86)Sr),值(0.70159)。同样侵入于小铺东二长花岗岩中的恰干昆多沟含角闪石石英正长岩(QGQS)也呈灰紫色,其结构和构造与OMAG非常相似。两个岩体在主量元素和REE图解上均呈现有规律的分布和一致的演化趋势。从QGQS到OMAG,SiO_2含量增加(从64.71%~64.83%到71.23%~74.31%)、全碱含量降低(从11.72%~11.79%到8.49%~9.87%)和Al_2O_3含量减少(从16.09%~16.19%到11.44%~13.34%)、稀土总量减少(从592.3×10^(-6)~656.0×10^(-6)到273.9×10^(-6)~405.9×10^(-6))、轻/重稀土比值降低(从18.2~20.1到4.4~6.0)、稀土配分曲线从平滑到Eu显著亏损。基于OMAG的岩相学、矿物学、地球化学、锆石年代学和与QGQS的对比研究,笔者认为奥姆尔塔格碱性花岗岩可能是由石英正长岩母岩浆经过分离结晶作用演化的产物,且这种石英正长岩岩浆起源于亏损地幔;根据哈尔里克造山带地质演化历史的分析,这两个岩体均形成于紧随主碰撞后的挤压-伸展转折阶段。 展开更多
关键词 distribution patterns fractional crystallization comparative study compression
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