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RAPID AND FACILE SYNTHESIS OF ACYL AZIDES FROM ACYL HaliDES USING A POLYMER-SUPPORTED AZIDE ION UNDER HETEROGENEOUS CONDITIONS

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Chinese Journal of Polymer Science 2013年第7期31卷 1002-1010页

作者： Mohammad ali Karimi Zarchi saeed Barani Department of Chemistry College of SciencesYazd University

In this article a rapid and facile method for synthesis of acyl azide is described. The cross-linked poly（N-methyl-4- vinylpyridinium） azide ion, [Pa-VP]N3 is prepared and used as an efficient polymeric reagent for synthesis of acyl azides from acyl halides at room temperature under heterogeneous conditions. Various benzoyl halides, with electron-withdrawing groups as well as electron-donating groups, were transformed into the corresponding benzoyl azides in high to excellent yields in short reaction times. The acyl azide products were characterized by FT-IR, and some of them were also characterized by IH- and/or 13C-NMR spectroscopy, and physical properties were compared to literature values of known compounds. The spent polymeric reagents can be regenerated and reused for several times without losing their activity. Relative to the reported methods, the present method has the advantages of operational simplicity, mild reaction conditions, fast reaction rates, simple reaction work-up and lower hazardous and potentially explosive nature. Also the present method is the first procedure for the synthesis of acyl azides from acyl halides by using a polymer-supported azide ion under heterogeneous conditions.

关键词： Acyl azide Acyl halide Polymeric reagent Heterogeneous condition.

Reservoir Potential Assessment of the Tortonian-Calabrian Sediments from Offshore Makran(Southwest Pakistan)through a Multidisciplinary Approach

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Acta Geologica Sinica(English Edition) 2023年第1期97卷 163-175页

作者： Natasha KHAN Awais ali Salahudin KHURSHEED Kashif ali Muhammad saeed Department of Earth Sciences Abbottabad University of Science and TechnologyHavelian 22500Khyber PakhtunkhwaPakistan National Centre of Excellence in Geology University of PeshawarPeshawar 25130Pakistan

The Tortonian–Calabrian strata of Offshore Makran(Pakistan)is investigated for the purpose of reservoir *** stratigraphy and petrophysics indicate that the Neogene sediments have tight reservoir potential with porosities in the range of 3%–9%and 40%–50%water *** mineralogical cross plots indicate a mixed lithology with an abundance of dolomite and calcite,together with minor quartz content and *** seismic interpretation demonstrates medium–high amplitude reflection patterns,mud diapirs coupled with onlapping strata and the occurrence of bottom simulating reflectors(BSRs).The BSRs are characterized by diminished amplitude,low continuity and exhibiting acoustic blanking *** high formation pressure results indicate overpressure zones,suggesting the occurrence of overpressured shales in the Jal *** presence of mud diapirs and gas chimneys are the result of tectonic forces acting at the junction of the Arabian,Indian and Eurasian plates,whereas,BSRs prove the existence of gas charged sediments supporting the formation of mud diapirism in the *** is concluded that the high rates of sedimentation during the Neogene are likely to have contributed to the development of the high formation *** mud weights,casing policies,pore pressure transients and geophysical inversion studies will help alleviate drilling risks in future exploration strategies.

关键词： seismic reservoirs overpressure Neogene Makran

Development of processing map for InX-750 superalloy using hyperbolic sinus equation and ANN model

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Rare Metals 2021年第12期40卷 3598-3607页

作者： saeed aliakbari Sani ali Khorram Abed Jaffari Golamreza Ebrahimi School of Metallurgy and Materials Engineering Iran University of Science and TechnologyNarmakTehran 16846-13114Iran Department of Mechanical Engineering KNToosi University of TechnologyTehran 19395-1999Iran Department of Material and Metallurgy Engineering Iran University of Industries and Mines(IUIM)Tehran 19537-65733Iran Materials and Polymers Engineering Department Faculty of EngineeringHakim Sabzevari UniversitySabzevar 96179-76487Iran

The aim of this study is to develop processing maps based on two models and compare them with conventional processing *** hyperbolic sinus constitutive equation and artificial neural network(ANN)approaches were used in this investigation to predict flow stress and to develop processing maps in various *** hot compression tests of InX-750 superalloy were carried out above the gamma prime phase temperature and within the temperature range of 1000-1150℃and strain rate of 0.001-1.000 s^(-1).The processing maps were conducted based upon dynamic material model(DMM)for data by experimental,constitutive equation and ANN *** processing maps drawn by either of the prediction methods show that the method developed by ANN data does not significantly differ from the experimental processing *** ANN approach is thus a suitable way to predict the flow stress as well as hot working processing map of engineering metals and materials.

关键词： Hot deformation Hyperbolic sine equation ANN model Prediction Processing map

Partial discharge detection and identification at low air pressure in noisy environment

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High Voltage 2021年第5期6卷 850-860页

作者： ali Nasr Esfahani saeed Shahabi Behzad Kordi Department of Electrical and Computer Engineering University of ManitobaWinnipegManitobaCanada

Increasing demand for electric power in more electric aircraft requires a higher operating voltage for the power system that leads to higher electric stress on the insulation *** at high altitudes where the electrical strength of air is weakened exposes the insulation system to even higher levels of electrical *** such,the probability of partial discharges(PD),which result in insulation degradation and failure,is *** presence of switching circuits in the power distribution system of the more electric aircraft is capable of producing high levels of *** noise in combination with the background noise and parasitic impedances will cause high amplitude ringing in the measured partial discharge signal ***,a method based on the combination of the wavelet and energy techniques is employed to detect PD pulses in a noisy environ-ment under the low air pressure *** verify the technique,a laboratory setup consisting of two separate PD sources mounted in low air pressure(33 kPa)chamber is developed where sine and square waveforms are used as the applied *** ob-tained results demonstrate that the proposed approach offers low computational complexity,high performance in PD phase localization,and robustness in a noisy environment.

关键词： insulation mounted noisy

Improved Performance for a Heterogeneous Satellite-Cooperative Network with Best Relay Node Selection

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China Communications 2019年第5期16卷 93-105页

作者： Pedram hajipour ali Shahzadi saeed Ghazi-Maghrebi Department of Communication College of Electrical EngineeringYadegar-e-Imam Khomeini (RAH) Shahr-e-rey BranchIslamic Azad UniversityTehranIran. Department of Electrical and Computer Engineering Semnan UniversitySemnanIran. Department of Communication College of Electrical EngineeringYadegar-e-Imam Khomeini (RAH) Shahr-e-rey BranchIslamic Azad UniversityTehranIran

Nowadays, hybrid satellite-terrestrial cooperative network has emerged as a key technology to provide a great variety of communication services. The deployment of this network will improve coverage and capacity in remote areas. Despite the benefits of this network, by increasing the number of users, communication efficiency based on interference management is a major challenge in satellite-based system. Also, the direct links between satellite system and the terrestrial equipment do not always have desirable channel condition. In order to avoid serious throughput degradation, choosing a cooperative relay node is very important. In this paper, Stackelberg game is exploited for interference management that is raised by satellites in down link over terrestrial equipment. Then, for interference management between ground station and relay node with other mobile users, CVX is used to allocate optimum power. Also, the best relay node in this structure is selected based on the harmonic mean function. Thus, the performance of the heterogeneous satellite-cooperative network is investigated based on three benchmarks, namely, successful transmission, energy consumption and outage probability. Finally, the simulation results showed the effect of proposed system model on the performance of next generation satellite networks.

关键词： heterogeneous Stackelberg game convex optimization relay node cooperative communication

Dependence of effective screening length in granular columns on bead and silo sizes and their ratio

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Chinese Physics B 2013年第5期22卷 591-594页

作者： Abdul Qadir Madad ali Shah saeed Ahmed Khan Department of Electrical Engineering Sukkur Institute of Business Administration

Apparent mass measurements at the bottom of silos have been carried out. An important parameter in the Janssen model known as the effective screening length has been investigated for different bead and silo diameters as well as of their ratios. It is found that the effective screening length augments with the grain diameter d in addition to the granular column size. It is also revealed that λ exhibits stronger correlation with the bead diameter than that of the silo. This phenomenon is attributed to the reduced-shielding of the vertical stresses to the horizontal ones.

关键词： granular systems granular solids static sand piles granular compaction

Chaos control of the power system via sliding mode based on fuzzy supervisor

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International Journal of Intelligent Computing and Cybernetics 2017年第1期10卷 68-79页

作者： Ahmad Sarani ali Abadi saeed Balochian Department of Electrical Engineering Gonabad BranchIslamic Azad UniversityGonabadIran

Purpose-The purpose of this paper is to address the problem of control in a typical chaotic power *** oscillations cannot only extremely endanger the stabilization of the power system but they can also not be controlled by adding the traditional ***,the sliding mode control based on a fuzzy supervisor can sufficiently ensure perfect tracking and controlling in the presence of ***-loop stability is proved using the Lyapunov stability *** simulation results show the effectiveness of the proposed method in damping chaotic oscillations of the power system,eliminating control signal chattering and also show less control effort in comparison with the methods considered in previous ***/methodology/approach-The sliding mode control based on a fuzzy supervisor can sufficiently ensure perfect tracking and controlling in the presence of ***-loop stability is proved using the Lyapunov stability ***-Closed-loop stability is proved using the Lyapunov stability *** simulation results show the effectiveness of the proposed method in damping chaotic oscillations of power system,eliminating control signal chattering and also less control effort in comparison with the methods considered in previous ***/value-Main contributions of the paper are as follows:the chaotic behavior of power systems with two uncertainty parameters and tracking reference signal for the control of generator angle and the controller signal are discussed;designing sliding mode control based on a fuzzy supervisor in order to practically implement for the first time;while the generator speed is constant,the proposed controller will enable the power system to go in any desired trajectory for generator angle at first time;stability of the closed-loop sliding mode control based on the fuzzy supervisor system is proved using the Lyapunov stability theory;simulation of the proposed controller shows that t

关键词： Fuzzy logic Stability Robust control Nonlinear control Adaptive control Fuzzy supervisor Chaotic power system Lyapunov Control effort

Voltammetric determination of stability constants of lead complexes with diallyl disulfide, dimethyl disulfide, and diallyl sulfide

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Chinese Chemical Letters 2016年第1期27卷 71-76页

作者： Mohammad ali Kamyabi Fatemeh Soleymani-Bonoti saeed Zakavi Department of Chemistry University of Zanjan Department of Chemistry Institute for Advanced Studies in Basic Sciences

The complexation of Pb^（2＋）by diallyl disulfide（DADS）, dimethyl disulfide（DMDS） and diallyl sulfide（DAS）has been studied by differential pulse voltammetry. Stability constants,（log b）, of the 1：1（PbL） and 1：2（PbL_2） complexes, where L = ligand, were found to be in the range of ca. 3.8-4.2 and 9.4-10.2,respectively. Complex formation is accompanied with a significant decrease in the peak current and the shift of the Pb2＋/Pb half-wave potential to a higher one upon the addition of the sulfur containing ligands（L）. The formation of 1：1 and 1：2 complexes, i.e., PbL^（2＋）and PbL_2^（2＋）was observed in the case of the three ligands. The consecutive formation constants of labile lead complexes with DADS, DMDS, and DAS were determined at 298 K by the method of De Ford and Hume. Apparently due to the large size of the lead ion,steric hindrance caused by the greater steric bulk of DADS compared to that of DMDS have little or no effects on the formation constants, so that very similar values were obtained in the case of the two ligands. Also, the possible participation of C=C double bonds in coordination with the metal center in the case of DADS appears to compensate for the steric effects caused by the larger size of this ligand. In agreement with the Jorgensen principle of symbiosis, the second formation constants were found to be approximately six orders of magnitude greater than the first ones.

关键词： Garlic oil Organic sulfur compounds Pb^(2+)-DADS,DMDS,and DAS complexes Stability constant

Forecasting soil temperature at multiple-depth with a hybrid artificial neural network model coupledhybrid firefly optimizer algorithm

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Information Processing in Agriculture 2018年第4期5卷 465-476页

作者： saeed Samadianfard Mohammad ali Ghorbani Babak Mohammadi Department of Water Engineering University of TabrizTabrizIran Engineering Faculty Near East University99138 NicosiaNorth CyprusMersin 10Turkey Department of Irrigation and Reclamation Engineering University of TehranKarajIran

Forecasting soil temperature at multiple depths is considered to be a core decision-making task for examining future changes in surface and sub-surface meteorological processes,land-atmosphere energy exchange,resilient agricultural systems for improved crop health and eco-environmental risk *** aim of this paper is to estimate monthly soil temperature(ST)at multiple depth:5,10,20,50 and 100 cm with a hybrid multi-layer perceptron algorithm integrated with the firefly optimizer algorithm(MLP-FFA).To develop the hybrid MLP-FFA model,the monthly ST and relevant meteorological variables for the city of Adana(Turkey)are collated for the period of 2000–*** of hybrid MLP-FFA model is drawn upon a limited set of predictors,denoted as soil depth,periodicity(or the respective month),air temperature,pressure and solar radiation,while the objective variable for MLP-FFA model is the forecasted ST at multiple *** the evaluate MLPFFA,statistical metrics applied to test the model’s performance are:the root mean square error(RMSE),mean absolute error(MAE),mean absolute percentage error(MAPE)and mean bias error(MBE)where the sign of the difference is also *** conjunction with statistical metrics,a Taylor diagram is utilized to visualize the degree of similarity between the observed and forecasted soil *** terms of the forecasted results,the hybrid MLPFFA model is seen to outperform the standalone MLP *** optimal MLP-FFA is attained for soil temperature forecasting at a depth of 20 cm(RMSE,MAPE of 0.546C,2.40%)whereas the optimal MLP is attained for soil temperature forecasting at a depth of 50 cm(RMSE of 0.544℃,2.21%).Conclusively,the study advocates through statistical metrics attained the better utility of the hybrid MLP-FFA hybrid *** its superior performance,it is ascertained that the hybrid MLP model integrated with Firefly optimizer is a qualified ancillary tool that can be applied to generate precise soil temperat

关键词： Artificial neural network Hybrid firefly algorithm Soil temperature Turkish State Meteorological Service