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Effect of plant extracts on activity of some defense enzymes of apple fruit in interaction with Botrytis cinerea

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Journal of Integrative Agriculture 2019年第1期18卷 115-123页

作者： jalal Gholamnezhad Department of Horticultural Sciences Faculty of Agriculture & Natural ResourcesArdakan University

The efficacy of seven plant extracts(neem,fennel,lavender,thyme,pennyroyal,salvia and asafetida) in controlling postharvest of apple(caused by Botrytis cinerea) was evaluated in vitro and in *** vitro,all plant extracts treatments inhibited spore *** rates of pore germination was 17.41 and 20.83% for neem extract treatment(methanolic and aqueous extracts,respectively) with significant difference compared to control(73.6 and 85.33%) for aqueous and methanol *** the storage conditions,the application of aqueous extract of neem(at concentration of 25%) resulted in 89.11% reduction of disease severity compared with the untreated *** of enzymes activity showed the plant extracts can increase the activity of peroxidase,phenylalanine ammonia-lyase,β-1,3-glucanase and polyphenol oxidase in the presence of pathogens,in apple ***,the results of this research revealed that application of neem extracts was more effective than the application of other plant *** to this study,it could be concluded that plant extracts may be useful to control postharvest disease as a safe alternative option to chemical fungicides.

关键词： Botrytis cinerea defense enzymes plant extracts spore germination

Optimal Estimation and Tracking Control for Variable-speed Wind Turbine with PMSG

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Journal of Modern Power Systems and Clean Energy 2020年第1期8卷 159-167页

作者： Farzad Bakhtiari jalal Nazarzadeh Shahed University TehranIran

Designing an optimal tracking controller and system observer is a nonlinear problem in the variable-speed wind energy conversion system(WECS).In this paper,an adjusted feedforward and feedback optimal controller with extended Kalman filter(EKF)is introduced to estimate and control the permanent magnet synchronous generator(PMSG)for the maximum power point tracking(MPPT)with several disturbances of the wind *** augmented model of wind turbine and PMSG is expanded,and then the parameters of the optimal controller and estimator are *** dynamic stability of the closed-loop system with feedback-feedforward controller(FFC),EKF and speed controller are *** compare the dynamic performance of EKF and FFC with the conventional controllers,numerical results are demonstrated with the disturbances of the wind speed and faults in power grid.

关键词： Permanent magnet synchronous generator(PMSG) maximum power point tracking(MPPT) extended Kalman filter(EKF) optimal tracking control

Optimization Methods of MPPT Parameters for PV Systems:Review,Classification,and Comparison

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Journal of Modern Power Systems and Clean Energy 2021年第2期9卷 225-236页

作者： jalal Dadkhah Mehdi Niroomand the Department of Electrical Engineering University of Is-fahanIsfahanIran the Department of Electrical and Computer Engineering University of ManitobaWinnipegCanada the Department of Electrical Engineering University of IsfahanIsfahanIran

To obtain efficient photovoltaic(PV)systems,optimum maximum power point tracking(MPPT)algorithms are *** efficiency of MPPT algorithms depends on two MPPT parameters,i.e.,perturbation amplitude and perturbation *** optimization of MPPT algorithms affect both the tracking speed and steady-state *** this paper,optimization methods of MPPT parameters are reviewed and classified into fixed and variable *** fixed MPPT parameters are constant during MPPT performance,and a trade-off should be made between the tracking speed and steady-state ***,the variable MPPT parameters will be changed to improve both the tracking speed and the steadystate ***,some of them are simulated,compared,and discussed to evaluate the real contributions of the optimization methods to the MPPT ***,significant features of the optimization methods,i.e.,noise immunity,robustness,and computation effort,are investigated.

关键词： Photovoltaic(PV)systems maximum power point tracking(MPPT) perturbation amplitude perturbation period

Nonlocal vibration analysis of circular double-layered graphene sheets resting on an elastic foundation subjected to thermal loading

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Acta Mechanica Sinica 2016年第5期32卷 841-853页

作者： Reza Ansari jalal Torabi Department of Mechanical Engineering University of Guilan

Based on the nonlocal elasticity theory, the vibration behavior of circular double-layered graphene sheets（DLGSs） resting on the Winkler- and Pasternak-type elastic foundations in a thermal environment is *** governing equation is derived on the basis of Eringen＇s nonlocal elasticity and the classical plate theory（CLPT）.The initial thermal loading is assumed to be due to a uniform temperature rise throughout the thickness direction. Using the generalized differential quadrature（GDQ）method and periodic differential operators in radial and circumferential directions, respectively, the governing equation is discretized. DLGSs with clamped and simply-supported boundary conditions are studied and the influence of van der Waals（vd W） interaction forces is taken into *** the numerical results, the effects of various parameters such as elastic medium coefficients, radius-to-thickness ratio,thermal loading and nonlocal parameter are examined on both in-phase and anti-phase natural frequencies. The results show that the thermal load and elastic foundation respectively decreases and increases the fundamental frequencies of DLGSs.

关键词： Circular DLGS Vibration Nonlocal theory Thermal environment Numerical solution

Sedimentological evidence of climate-tectonic interaction in the upper Satluj catchment of NW Himalaya

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Journal of Mountain Science 2024年第6期21卷 1978-1991页

作者： JOSHI Moulishree jalal Poonam Department of Geology Kumaun UniversityNainitalUttarakhand 263001India

Quaternary valley fill deposits in the Upper Satluj Valley of NW Himalaya act as archives of changing climate-tectonic dynamics in a *** landforms help in decoding the relationship between climate and *** region is traversed by several active faults and thrusts such as the Kaurik-Chango Fault(KCF)and Sangla Detachment(SD),thereby making upper Satluj Valley tectonically *** parameters such as width of valley floor(Vfw),Normalized Steepness Index(KSn)and geomorphological evidences such as the presence of huge strath terraces,narrowing of the river valley and palaeolake deposits point towards the tectonically active nature of the *** arid,high elevation region is also climatically sensitive as it falls in a transient climatic zone which receives rainfall only during abnormal monsoon *** rainfall causes outburst floods,a common phenomenon in the area due to the blocking of headwater in the upper reaches of the Satluj *** a result,the Quaternary sequence is modified from time to *** transition from hypo concentrated deposits to channel deposits and ponding events are prominent in the depositional sequence,resulting from a response to *** studied Quaternary sediments reveal that the Trans-Himalayan region of the upper Satluj valley is affected by tectonic-climate variability,making it vulnerable to geohazards.

关键词： Himachal Pradesh Quaternary Lithofacies association Tectonics Climate

Regularity classification and corresponding analysis method requirements of horizontally curved bridges with unequal pier heights

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Earthquake Engineering and Engineering Vibration 2023年第2期22卷 549-571页

作者： Mohammad jalal Maleki-amin Shahrokh Maalek School of Civil Engineering Tehran UniversityTehran 11155-4563Iran Iranian Bridge Engineering Association Tehran 36481684Iran

The seismic behavior of horizontally curved bridges,particularly with unequal height piers,is more complicated than that of straight bridges due to their geometric *** this study,the seismic responses of several horizontally curved single-column-bent viaducts with various degrees of curvature and different pier heights have been investigated,employing three different analysis approaches:namely,modal pushover analysis,uniform load method,and nonlinear time history *** the investigated bridge configurations and utilizing the most common regularity indices,the results indicate that viaducts with 45-degree and 90-degree deck subtended angles can be categorized as regular and moderately irregular,respectively,while the bridges with 180-degree deck subtended angle are found to be highly ***,the viaducts whose pier heights are asymmetric may be considered as irregular for almost all ranges of the deck subtended *** effects of higher transverse and longitudinal modes are discussed and the minimum analysis requirements are identified to assess the seismic response of such bridge configurations for design *** the Regularity Indices used here are useful tools to distinguish between regular and irregular bridges,further studies are needed to improve their reliability.

关键词： horizontally curved bridges unequal height piers pushover analysis regularity index seismic analysis and response

An online estimator for rotor resistance in vector drives of induction machines based on Walsh functions

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Control Theory and Technology 2014年第4期12卷 402-412页

作者： Hamidreza SHIRAZI jalal NAZARZADEH Engineering Faculty Shahed University

In a modern electrical driver, rotor field oriented control an appropriate transient response. In this method, the space （RFOC） method has been used to achieve a good performance and vector of the rotor flux comes handy by the rotor resistance value. The rotor resistance is one of the important parameters which varies according to motor speed and room temperature alteration. In this paper, a new on-line estimation method is utilized to obtain the rotor resistance by using Walsh functions domain. The Walsh functions are one of the most applicable functions in piecewise constant basis functions （PCBF） to solve dynamic equations. On the other hand, an integral operational matrix is used to simplify the process and speed of the computation algorithm. The simulations results show that the proposed method is capable of solving the dynamic equations in an electrical machine on a time interval which robustly estimates the rotor resistance in contrast with injection noises.

关键词： Vector control Walsh functions Operational matrix Rotor resistance estimation

Green Recyclable CuO-CeO_(2)Nanocomposite Catalyzed Amination of Aryl Halides with Aqueous Ammonia in Water

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Chinese Journal of Chemistry 2014年第5期32卷 396-398页

作者： jalal Albadi Azam Mansournezhad Behbahan Khatam Alanbia University of Technology BehbahanIran Department of Chemistry Gachsaran BranchIslamic Azad UniversityGachsaranIran

CuO-CeO_(2)nanocomposite as a green recyclable catalyst,catalyzed amination of aryl halides with aqueous am-monia in *** catalyst can be easily recovered by simple filtration and recycled up to 5 consecutive runs with consistent *** procedure provides some advantages such as simple work-up,clean procedure,relatively short reaction times and high yields of the products.

关键词： CuO-CeO_(2)nanocomposite amination aryl halides ammonia

Hybrid extended Fourier series for optimal control of nonlinear algebraic dynamical systems

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控制理论与应用（英文版） 2011年第4期9卷 487-492页

作者： jalal NAZARZADEH Hamidreza RADMANESH Department of Electrical Engineering Shahed University

The paper introduces a new method for finding optimal control of algebraic dynamic systems. The structure of algebraic dynamical systems is nonlinear with quadratic and bilinear terms. A new hybrid extended Fourier series is introduced, and state and control variables of the system are expanded by this series. Moreover, properties of new series are presented, and integration and product operational matrices are obtained. Using operational matrices, optimal control of the systems is converted to a set of simultaneous nonlinear algebraic relations. An illustrative example is included to compare our results with those in the literature.

关键词： Bilinear systems Hybrid extended Fourier series Nonlinear algebraic dynamic systems Quadratic systems Optimal control