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Determination of Ten Kinds of Alpha-2 Agonists Residues in Animal Derived Food by UHPLC-Triple Quadrupole/Composite Linear Ion Trap Mass Spectrometry
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作者 Fang LI Xuemei LI +3 位作者 Xiangang LI Sining LIU Sha LIU Ying WANG 《Plant Diseases and Pests》 2024年第1期28-32,共5页
[Objectives]The paper was to establish an ultra high performance liquid chromatography-quadrupole/linear ion trap complex mass spectrometry for the determination of 10 kinds ofα2-receptor agonists in animal derived f... [Objectives]The paper was to establish an ultra high performance liquid chromatography-quadrupole/linear ion trap complex mass spectrometry for the determination of 10 kinds ofα2-receptor agonists in animal derived food.[Methods]The samples were extracted with sodium carbonate buffer solution and ethyl acetate,and analyzed by mass spectrometry after solid phase extraction and high performance liquid chromatography separation.[Results]Ten kinds ofα2-receptor agonists showed a good linear relationship in the range of 1-100μg/mL,with the average recovery of over 69%and the relative standard deviation less than 8.32%.The detection limit of 10 kinds of α_(2)-receptor agonists was up to 1μg/kg.[Conclusions]The method has good selectivity and strong anti-interference ability,and can meet the requirements of 10 kinds ofα2-receptor agonists residues in animal derived food. 展开更多
关键词 Animal derived food α_(2)-receptor agonist Solid-phase extraction Ultra-high performance liquid phase-triple quadrupole/linear ion trap composite mass spectrometry
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Pressure transient analysis of a finite-conductivity multiple fractured horizontal well in linear composite gas reservoirs 被引量:1
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作者 REN Jun-jie GAO Yang-yang +2 位作者 ZHENG Qiao GUO Ping WANG De-long 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第3期780-796,共17页
Faulted gas reservoirs are very common in reality,where some linear leaky faults divide the gas reservoir into several reservoir regions with distinct physical properties.This kind of gas reservoirs is also known as l... Faulted gas reservoirs are very common in reality,where some linear leaky faults divide the gas reservoir into several reservoir regions with distinct physical properties.This kind of gas reservoirs is also known as linear composite(LC)gas reservoirs.Although some analytical/semi-analytical models have been proposed to investigate pressure behaviors of producing wells in LC reservoirs based on the linear composite ideas,almost all of them focus on vertical wells and studies on multiple fractured horizontal wells are rare.After the pressure wave arrives at the leaky fault,pressure behaviors of multiple fractured horizontal wells will be affected by the leaky faults.Understanding the effect of leaky faults on pressure behaviors of multiple fractured horizontal wells is critical to the development design.Therefore,a semi-analytical model of finite-conductivity multiple fractured horizontal(FCMFH)wells in LC gas reservoirs is established based on Laplace-space superposition principle and fracture discrete method.The proposed model is validated against commercial numerical simulator.Type curves are obtained to study pressure characteristics and identify flow regimes.The effects of some parameters on type curves are discussed.The proposed model will have a profound effect on developing analytical/semi-analytical models for other complex well types in LC gas reservoirs. 展开更多
关键词 semi-analytical model linear composite gas reservoir multiple fractured horizontal well finite-conductivity hydraulic fracture pressure behavior
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The Model for Linear Magnetoresistance of Two-Dimensional Metal-Semiconductor Composites with Interfacial Shells
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作者 徐洁 王国栋 +2 位作者 李山东 李强 高小洋 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第9期123-127,共5页
A metal-semiconductor composite with the interracial shells is investigated theoretically for the large linear mag- netoresistance effect of high doping Ag2+δ Se and Ag2+δ te materials. The magnetoresistance (MR... A metal-semiconductor composite with the interracial shells is investigated theoretically for the large linear mag- netoresistance effect of high doping Ag2+δ Se and Ag2+δ te materials. The magnetoresistance (MR) of composites is a function of the magnetic field, temperature, the conductivities of two phases without magnetic field, and the thickness and conductivity of the interracial shells. The MR increases with the increase of the magnetic field and with the decrease of temperature, and no saturation is found even under the high magnetic field. Moreover, it is interestingly found that the interracial shell is an important factor for the MR of the composites. The MR increases with the thickness and the conductivity of the interfacial shells. Lastly, the theoretical results on the MR are compared with the experimental data. It is found that the value of the MR of the composite with the interfacial shell is larger than that without the interfacial shell. 展开更多
关键词 The Model for linear Magnetoresistance of Two-Dimensional Metal-Semiconductor composites with Interfacial Shells Ag MR
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On Completeness for a 3-D Linear Theory of Composite Laminate
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作者 蒋友谅 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第7期679-688,共10页
In Ref [1] a model of 3-D composite laminate theory was described In the present paper,based on the basic equations about 3-D linear elasticity and classicalrariational principles,by the block matrix operation and the... In Ref [1] a model of 3-D composite laminate theory was described In the present paper,based on the basic equations about 3-D linear elasticity and classicalrariational principles,by the block matrix operation and the Lagrange's method of multipliers a series of basic equations and variational principles are obtained whichare more complere and more systematic than that in Ref [1] 展开更多
关键词 composite malerials. coinposite laminate. 3-D linear elasticity
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Multi-Level Inverter Linear Predictive Phase Composition Strategy for UPQC
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作者 M.Hari Prabhu K.Sundararaju 《Intelligent Automation & Soft Computing》 SCIE 2023年第6期2947-2958,共12页
The power system is facing numerous issues when the distributed gen-eration is added to the existing system.The existing power system has not been planned with flawless power quality control.These restrictions in the ... The power system is facing numerous issues when the distributed gen-eration is added to the existing system.The existing power system has not been planned with flawless power quality control.These restrictions in the power trans-mission generation system are compensated by the use of devices such as the Static Synchronous Compensator(STATCOM),the Unified Power Quality Con-ditioner(UPQC)series/shunt compensators,etc.In this work,UPQC’s plan with the joint activity of photovoltaic(PV)exhibits is proposed.The proposed system is made out of series and shunt regulators and PV.A boost converter connects the DC link to the PV source,allowing it to compensate for voltage sags,swells,vol-tage interferences,harmonics,and reactive power issues.In this paper,the fea-tures of a seven-level Cascaded H-Bridge Multi-Level idea are applied to shunt and series active filter changeovers to reduce Total Harmonic Distortion and com-pensate for voltage issues.Despite its power quality capacity for common cou-pling,the proposed system can inject the grid’s dynamic power.During voltage interference,it can also provide a piece of delicate burden power.The simulation is carried out with the help of MATLAB/SIMULINK programming,and the results are compared to those of other conventional methods. 展开更多
关键词 Unified power quality conditioner PHOTOVOLTAIC linear predictive phase composition total harmonic distortion
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A NEW WELL TEST MODEL FOR A TWO-ZONE LINEAR COMPOSITE RESERVOIR WITH VARIED THICKNESSES 被引量:12
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作者 ZHANG Lie-hui GUO Jing-jing LIU Qi-guo 《Journal of Hydrodynamics》 SCIE EI CSCD 2010年第6期804-809,共6页
This article presents a new well test model for two-zone linear composite reservoirs, where the rock and fluid properties as well as the formation thicknesses on both sides of the discontinuity are distinctly differen... This article presents a new well test model for two-zone linear composite reservoirs, where the rock and fluid properties as well as the formation thicknesses on both sides of the discontinuity are distinctly different. An analytical solution of pressure-transient behavior for a line-source, constant-rate well in this type of reservoir configuration is obtained with Fourier space transformation and Laplace transformation. By applying Duhamel principle, the wellbore storage and skins effects can easily be included. A set of type curves are generated and the sensitivities of the relevant parameters are discussed. A new correlating parameter MhDl√ηD is proposed to identify the pressure response in the pressure derivative curve. The model as well as the corresponding type curves are quite general that they are useful in predicting the production performance or analyzing the production data from this type of well-reservoir systems. 展开更多
关键词 non-uniform thickness linear composite well test model type curve
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Template-based smoothing functions for data smoothing in Geodesy 被引量:1
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作者 M.Kiani 《Geodesy and Geodynamics》 2020年第4期300-306,共7页
This paper is aimed at the derivation of a discrete data smoothing function for the discrete Dirichlet condition in a regular grid on the surface of a spheroid.The method employed here is the local L^2-seminorm minimi... This paper is aimed at the derivation of a discrete data smoothing function for the discrete Dirichlet condition in a regular grid on the surface of a spheroid.The method employed here is the local L^2-seminorm minimization,through Euler-Lagrange method,for the Beltrami operator.The method results in a weighted average of the surrounding points in a te mplate based on the first order Taylor expansion of the unknown function under consideration.The coefficients of the weighted average are calculated and used to smooth the Geoid height data in Iran,derived from the EGM2008 geopotential model. 展开更多
关键词 Minimization problem Regular grid linear composition Beltrami operator Smoothing function
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Very Short-Term Probabilistic Prediction Method for Wind Speed Based on ALASSO-Nonlinear Quantile Regression and Integrated Criterion 被引量:1
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作者 Yan Zhou Yonghui Sun +4 位作者 Sen Wang Linquan Bai Dongchen Hou Rabea Jamil Mahfoud Peng Wang 《CSEE Journal of Power and Energy Systems》 SCIE EI CSCD 2023年第6期2121-2129,共9页
To enhance the performance of the prediction intervals (PIs), a novel very short-term probabilistic prediction method for wind speed via nonlinear quantile regression (NQR) based on adaptive least absolute shrinkage a... To enhance the performance of the prediction intervals (PIs), a novel very short-term probabilistic prediction method for wind speed via nonlinear quantile regression (NQR) based on adaptive least absolute shrinkage and selection operator (ALASSO) and integrated criterion (IC) is proposed. The ALASSO method is studied for shrinkage of output weights and selection of variables. Furthermore, for the better performance of PIs, composite weighted linear programming (CWLP) is proposed to modify the conventional linear programming cost function of quantile regression (QR), by combining it with Bayesian information criterion (BIC) as an IC to optimize the coefficients of PIs. Then, the multiple fold cross model (MFCM) is utilized to improve the PIs performance. Multistep probabilistic prediction of 15-minute wind speed is performed based on the real wind farm data from the northeast of China. The effectiveness of the proposed approach is validated through the performances' comparisons with conventional methods. 展开更多
关键词 composite weighted linear programming least absolute shrinkage and selection operator integrated criterion wind speed
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Linear fractional composition operators on the Dirichlet space in the unit ball 被引量:1
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作者 ZHOU ZeHua YUAN Cheng 《Science China Mathematics》 SCIE 2009年第8期1661-1670,共10页
We investigate the adjoints of linear fractional composition operators C ? acting on classical Dirichlet space D(B N ) in the unit ball B N of ? N , and characterize the normality and essential normality of C ? on D(B... We investigate the adjoints of linear fractional composition operators C ? acting on classical Dirichlet space D(B N ) in the unit ball B N of ? N , and characterize the normality and essential normality of C ? on D(B N ) and the Dirichlet space modulo constant function D 0(B N ), where ? is a linear fractional map ? of B N . In addition, we also show that for any non-elliptic linear fractional map ? of B N , the composition maps σ o ? and ? o σ are elliptic or parabolic linear fractional maps of B N . 展开更多
关键词 linear fractional composition operators Dirichlet space ADJOINTS essential normality 47B38 46E15 32A37
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Linear Combinations of Composition Operators on Weighted Dirichlet Spaces 被引量:1
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作者 CHEN Peng 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2015年第5期369-374,共6页
In this paper, linear combinations of composition operators acting on weighted Dirichlet spaces are studied. By using the first derivative of the kernel function, we obtain a lower estimate for the essential norms of ... In this paper, linear combinations of composition operators acting on weighted Dirichlet spaces are studied. By using the first derivative of the kernel function, we obtain a lower estimate for the essential norms of these operators acting on the Dirichlet space D and S2. For general weighted Dirichlet space, by using complex interpolation methods, we characterize the compactness of these operators induced by linear fractional self-maps of the disk. 展开更多
关键词 linear combinations of composition operator compact operator weighted Dirichlet spaces complex interpolation
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Gradient estimates for parabolic systems from composite material
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作者 LI HaiGang LI YanYan 《Science China Mathematics》 SCIE CSCD 2017年第11期2011-2052,共42页
In this paper, we derive W^(1,∞) and piecewise C^(1,α) estimates for solutions, and their t-derivatives, of divergence form parabolic systems with coefficients piecewise H¨older continuous in space variables x ... In this paper, we derive W^(1,∞) and piecewise C^(1,α) estimates for solutions, and their t-derivatives, of divergence form parabolic systems with coefficients piecewise H¨older continuous in space variables x and smooth in t. This is an extension to parabolic systems of results of Li and Nirenberg [Comm Pure Appl Math, 2003, 56:892–925] on elliptic systems. These estimates depend on the shape and the size of the surfaces of discontinuity of the coefficients, but are independent of the distance between these surfaces. 展开更多
关键词 gradient estimates parabolic system composite material linear system of elasticity
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The principle of optimization of binary mobile phase composition of multi-step linear gradient elution
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作者 ZOU Han-Fa ZHANG Yu-Kui +2 位作者 DONG Li-Fu BAO Mian-Sheng LU Pei-Zhang 《Acta Chimica Sinica English Edition》 SCIE CAS CSCD 1989年第6期511-519,共1页
The basic principle of optimal method called “moving overlapping resolution mapping Method” to select the optimal binary mobile phase composition of multi-step linear gradient liquid chromatography is discussed with... The basic principle of optimal method called “moving overlapping resolution mapping Method” to select the optimal binary mobile phase composition of multi-step linear gradient liquid chromatography is discussed with simultaneously considering effects of position of solute inside the column and mobile phase composition on peak resolution and retention value, then a BASIC program based on this principle is developed in IBM-PC computer. The validities of both principle of optimization and BASIC program are confirmed by separation of samples Containing bile acids and PAHs in RP-HPLC. 展开更多
关键词 time LENGTH The principle of optimization of binary mobile phase composition of multi-step linear gradient elution
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Pressure transient analysis for a fractured well in a stress-sensitive tight multi-medium oil reservoir
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作者 Wancai NIE Tingshan ZHANG +1 位作者 Xiaopeng ZHENG Jun LIU 《Frontiers of Earth Science》 SCIE CSCD 2021年第4期719-736,共18页
Tight multi-medium oil reservoirs are the main source of hydrocarbon resources around the world.Acid fracturing is the most effective technology to improve productivity in such reservoirs.As carbonates are primarily c... Tight multi-medium oil reservoirs are the main source of hydrocarbon resources around the world.Acid fracturing is the most effective technology to improve productivity in such reservoirs.As carbonates are primarily composed of dolomite and calcite,which are easily dissolved by hydrochloric acid,high-permeability region will be formed near the well along with the main artificial fracture when acid fracturing is implemented in tight multi-medium oil reservoirs.In this study,a comprehensive composite linear flow model was developed to simulate the transient pressure behavior of an acid fracturing vertical well in a naturally fractured vuggy carbonate reservoir.By utilizing Pedrosa's substitution,perturbation,Laplace transformation and Stehfest numerical inversion technol-ogy,the pressure behavior results were obtained in real time domain.Furthermore,the result of this model was validated by comparing with those of previous literature.Additionally,the influences of some prevailing parameters on the type curves were analyzed.Moreover,the proposed model was applied to an acid fracturing well to evaluate the effectiveness of acid fracturing measures,to demonstrate the practicability of the proposed model. 展开更多
关键词 tight multi-medium oil reservoir acid fracturing stress-sensitive permeability composite linear flow
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