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Gardaneh Salavat porphyry copper system: Is it about metal endowment or fertility of the porphyritic intrusion?

Acta Geochimica 2022年第3期41卷 496-514页

作者： seyyed reza mashhadi Department of Geoscience Aarhus UniversityHøeghGuldbergs Gade 28000 Aarhus CDenmark

Gardaneh Salavat porphyry copper system is located in the northwest of Iran. It comprises a quartz diorite to diorite porphyritic intrusion that created extensive alteration haloes in the host rocks. Despite all technical considerations, the exploration activities did not yield to ore discovery. As the matter of fact, all of the geological,geophysical, and geochemical characteristics of a porphyry Cu-Au deposit exist but there is no economic mineralization. Detailed examinations suggest that the only reasonable explanation can be related to the infertility or low metal endowment of the porphyritic intrusion. The reasons include(1) anomalous ranges of Cu, Au, and Mo rather than economic ore grades,(2) weakly development of potassic alteration,(3) probably sulfur saturation of magma that occurred before intrusion emplacement in the host rocks, and(4) probably low metal endowment in the regional scale and the lack of known porphyry copper deposits in close neighborhoods. It is tried to test the proposed hypothesis with the introduced fertility indicators based on major and trace element geochemistry. However,current fertility indicators could not prove or reject the proposed hypothesis for Gardaneh Salavat porphyritic intrusion because of the high-K calc-alkaline to shoshonitic nature of the intrusive rocks together with the unavailability of relatively fresh/unaltered samples. This case study is notable to examine because(1) it shows that characterization of fertile from barren intrusions seems to be as important as vectoring towards concealed porphyry copper deposits, especially while dealing with deep exploration targets that are associated with high financial risks, and(2) it highlights the inefficiencies and uncertainties in introduced magma fertility indicators for porphyry copper intrusions. As a result, it is of high importance to conduct an overarching investigation on other possible fertility indicators as a fundamental need for the future of the exploration

关键词： Porphyry Copper Fertility Metal endowment Barren intrusion

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Correction:Gardaneh Salavat porphyry copper system:Is it about metal endowment or fertility of the porphyritic intrusion?

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Acta Geochimica 2022年第6期41卷 1123-1123页

作者： seyyed reza mashhadi Department of Geoscience Aarhus UniversityHøegh-Guldbergs Gade 28000Aarhus CDenmark

Correction to:Acta Geochim(2022)41(3):496-514 https://***/10.1007/s11631-022-00535-0 In the original publication of the article,under the section“4.1 Proposed hypothesis for Gardaneh Salavat porphyry system”,on page 509,the following sentence“Du and Audétat(2020)believed that early sulfide saturation is not necessarily detrimental to deposit formation or fertility of porphyritic *** proving this fact”was included incorrectly.

关键词： porphyry intrusion deposit

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Effect of metal oxide arrester on the chaotic oscillations in the voltage transformer with nonlinear core loss model using chaos theory

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Chinese Physics B 2014年第1期23卷 480-488页

作者： Hamid reza Abbasi Ahmad Gholami seyyed Hamid Fathi Ataollah Abbasi Iran University of Science & Technology Electrical & Electronic Engineering Department Narmak *** Tehran Iran Amirkabir University Electrical Engineering Department Tehran 64540 Iran

In this paper, controlling chaos when chaotic ferroresonant oscillations occur in a voltage transformer with nonlin- ear core loss model is performed. The effect of a parallel metal oxide surge arrester on the ferroresonance oscillations of voltage transformers is studied. The metal oxide arrester （MOA） is found to be effective in reducing ferroresonance chaotic oscillations. Also the multiple scales method is used to analyze the chaotic behavior and different types of fixed points in ferroresonance of voltage transformers considering core loss. This phenomenon has nonlinear chaotic dynamics and includes sub-harmonic, quasi-periodic, and also chaotic oscillations. In this paper, the chaotic behavior and various ferroresonant oscillation modes of the voltage transformer is studied. This phenomenon consists of different types of bifur- cations such as period doubling bifurcation （PDB）, saddle node bifurcation （SNB）, Hopf bifurcation （HB）, and chaos. The dynamic analysis of ferroresonant circuit is based on bifurcation theory. The bifurcation and phase plane diagrams are il- lustrated using a continuous method and linear and nonlinear models of core loss. To analyze ferroresonance phenomenon, the Lyapunov exponents are calculated via the multiple scales method to obtain Feigenbaum numbers. The bifurcation diagrams illustrate the variation of the control parameter. Therefore, the chaos is created and increased in the system.

关键词： ferroresonance chaos theory metal oxide arrester Lyapunov exponent

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Assessment of electrostatic discharge sensitivity of nitrogen-rich heterocyclic energetic compounds and their salts as high energy-density dangerous compounds:A study of structural variables

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Defence Technology（防务技术） 2024年第9期39卷 15-22页

作者： Mohammad Hossein Keshavarz Sedigheh Heydari Bani reza Bakhtiari seyyed Hesamodin Hosseini Faculty of Applied Sciences Malek Ashtar University of TechnologyIsfahan 177415875Iran

Nitrogen-rich heterocyclic energetic compounds(NRHECs)and their salts have witnessed widespread synthesis in recent *** substantial energy-density content within these compounds can lead to potentially dangerous explosive reactions when subjected to external stimuli such as electrical ***,developing a reliable model for predicting their electrostatic discharge sensitivity(ESD)becomes *** study proposes a novel and straightforward model based on the presence of specific groups(-NH_(2) or-NH-,-N=N^(+)-O^(-)and-NNO_(2),-ONO_(2) or-NO_(2))under certain conditions to assess the ESD of NRHECs and their salts,employing interpretable structural *** a comprehensive dataset comprising 54 ESD measurements of NRHECs and their salts,divided into 49/5 training/test sets,the model achieves promising *** Root Mean Square Error(RMSE),Mean Absolute Error(MAE),and Maximum Error for the training set are reported as 0.16 J,0.12 J,and 0.5 J,***,the ratios RMSE(training)/RMSE(test),MAE(training)/MAE(test),and Max Error(training)/Max Error(test)are all greater than 1.0,indicating the robust predictive capabilities of the *** presented model demonstrates its efficacy in providing a reliable assessment of ESD for the targeted NRHECs and their salts,without the need for intricate computer codes or expert involvement.

关键词： Electrostatic discharge sensitivity Heterocyclic energetic compounds containing azole compound Interpretable structural parameter Safety

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Characterization and corrosion behavior of Al-Co-rare earth(Ce-La)amorphous alloy

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Journal of Rare Earths 2023年第5期41卷 771-779,I0006页

作者： Seyed Ali Mousavi Sayed Hamid Hashemi Ali Ashrafi reza Shoja Razavi seyyed Mehdi Ghazi Mirsaeed Faculty of Materials and Manufacturing Technologies Malek Ashtar University of TechnologyTehran167885611Iran Department of Materials Engineering Malek Ashtar University of TechnologyIsfahanShahin-shahrIran Department of Materials Engineering Isfahan University of TechnologyIsfahan***Iran

A new Al-based amorphous alloy with excellent corrosion resistance and high thermal stability was produced in the Al-Co-RE(Ce-La)*** this regard,two different amorphous-nanocrystalline ribbons:Al_(87.6)-Co_(6.4)-Ce_(3.8-)La_(2.2)(M_(1))and Al_(82.3)-Co_(10.1)-Ce_(4.8)-La_(2.8)(M_(2))were prepared using melt *** results reveal the supercooled liquid region(ATx)of 218℃which shows that the M2alloy has higher thermal stability in comparison to the *** M2ribbons present the superior corrosion resistance because of the formation of amorphous *** icorr,Ecorr,Epit,and Epit-Ecorrvalues of fully amorphous Al-Co-Ce-La metallic ribbons have a better trend of anti-corrosion performance compared to other crystalline and amorphous aluminum alloys.

关键词： Amorphous alloys Melt-spinning Rare earth metal Corrosion behavior

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A new multilevel voltage source inverter configuration with minimum number of circuit elements

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Journal of Central South University 2017年第4期24卷 912-920页

作者： Mohammad reza Jannati Oskuee Masoumeh Karimi Yahya Naderi Sajad Najafi Ravadanegh seyyed Hossein Hosseini Smart Distribution Grid Research Lab. Electrical Engineering Department Azarbaijan Shahid Madani University Tabriz Iran Faculty of Electrical and Computer Engineering University of Tabriz Tabriz Iran

An advanced configuration for multilevel voltage source converters is proposed. The proposed converter is able to apply asymmetrical DC sources. The configuration of the proposed inverter is well designed in order to provide the maximum number of voltage levels in output terminals using lower number of circuit devices. The authority of the proposed inverter versus the conventional H-bridge cascaded inverter and the most recently introduced ones, is verified with a provided comparison study. The proposed inverter is able to generate the desired voltage levels using a lower number of circuit devices including power semi-conductor switches, IGBTs, diodes, related gate driver circuits of switches and DC voltage sources. As a result, the total cost and installation area are considerably reduced and the control scheme gets simpler. To confirm the feasibility of the proposed multilevel structure, both the simulation and experimental results are provided and compared which shows good agreements.

关键词： multilevel voltage source inverter reduction of circuit components symmetric inverter asymmetric inverter

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Toward a More Accurate Web Service Selection Using Modified Interval DEA Models with Undesirable Outputs

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Computer Modeling in Engineering & Sciences 2020年第5期123卷 525-570页

作者： Alireza Poordavoodi Mohammad reza Moazami Goudarzi Hamid Haj seyyed Javadi Amir Masoud Rahmani Mohammad Izadikhah Department of Computer Engineering Borujerd BranchIslamic Azad UniversityBorujerdIran Department of Mathematics Borujerd BranchIslamic Azad UniversityBorujerdIran Department of Mathematics and Computer Science Shahed UniversityTehranIran Department of Computer Science Khazar UniversityBakuAzerbaijan Department of Mathematics Arak BranchIslamic Azad UniversityArakIran

With the growing number of Web services on the internet,there is a challenge to select the best Web service which can offer more quality-of-service(QoS)values at the lowest *** challenge is the uncertainty of QoS values over time due to the unpredictable nature of the *** this paper,we modify the interval data envelopment analysis(DEA)models[Wang,Greatbanks and Yang(2005)]for QoS-aware Web service selection considering the uncertainty of QoS attributes in the presence of desirable and undesirable *** conduct a set of experiments using a synthesized dataset to show the capabilities of the proposed *** experimental results show that the correlation between the proposed models and the interval DEA models is ***,the proposed models provide almost robust results and represent more stable behavior than the interval DEA models against QoS ***,we demonstrate the usefulness of the proposed models for QoS-aware Web service *** results indicate that the proposed models significantly improve the fitness of the resultant compositions when they filter out unsatisfactory candidate services for each abstract service in the preprocessing *** models help users to select the best possible cloud service considering the dynamic internet environment and they help service providers to improve their Web services in the market.

关键词： Cloud computing interval data envelopment analysis interval entropy Web service selection undesirable outputs

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A mild and efficient method for the methoxymethylation and acetylation of alcohols promoted by benzyltriphenylphosphonium tribromide

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Chinese Chemical Letters 2010年第10期21卷 1187-1190页

作者： Farhad Shirini Gholam Hossein Imanzadeh seyyed Ali reza Mousazadeh Iraj Mohammadpoor-Baltork Masoumeh Abedin Department of Chemistry College of ScienceUniversity of Guilan Department of Chemistry College of ScienceUniversity of Mohaghegh-Ardabili Department of Chemistry College of ScienceIsfahan University

A mild and efficient method for the conversion of alcohols to their corresponding methoxymethyl ethers and acetates using benzyltriphenylphosphonium tribromide （BTPTB） as catalyst is described. All reactions were pe... 详细信息

关键词： Benzyltriphenylphosphonium tribromide Alcohols Methoxymethylation Acetylation Heterogeneous reaction conditions

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聚(4-乙烯基吡啶丁烷磺酸)硫酸氢盐:一个高效的多相聚(离子液体)固体酸催化剂用于无溶剂条件下一锅法合成1-酰氨基-2-萘酚和取代喹啉(英文)

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催化学报 2013年第10期34卷 1861-1868页

作者： Ali reza Kiasat Arash Mouradzadegun seyyed Jafar Saghanezhad Chemistry Department College of ScienceShahid Chamran University

Poly(4-vinylpyridinium butane sulfonic acid) hydrogen sulfate has been used as an efficient dual acidic catalyst for the one-pot preparation of 1-amidoalkyl-2-naphthols and substituted quinolines under solvent-free *** catalyst was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and thermo-gravimetric analysis. The results revealed several advantages to our new catalyst system,including its reusability,facile work-up procedure, eco-friendly reaction conditions,short reaction time,and high product yields.

关键词： Solvent-free β-Naphthol Poly(ionic liquid) Acetamide Quinoline 2-Aminobenzophenone

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The Determination of Promising Mineral Zones in 1:100,000 Varamin Sheet Based on Geochemical Studies (Heavy Minerals)

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Open Journal of Geology 2016年第8期6卷 745-756页

作者： seyyed reza Mortazavi Ghodratollah Mohammadi Department of Mining Engineering Islamic Azad University South Tehran Branch Tehran Iran

In many parts of the world, data obtained from geochemical exploration of stream sediments are integrated with geological and geophysical data as one of the most efficient methods of exploring potential deposits at regional and semi-detailed scales. The aim of regional investigation is to study large areas to identify anomalies that might have been arisen from increased concentrations of an element or some elements in a region. A total of 78 geochemical samples were taken from Varamin sheet to identify regions of anomalies. The following information was used to perform a detailed geochemical exploration, in particular for geochemical sampling. 1) 1:100,000 geological map of Varamin. 2) 1:50,000 topographic maps of the region. 3) 1:100,000 airborne geophysical map of the region to locate shallow intrusions and hidden faults. The sampling network was designed using the above data and the analysis of 1:500,000 topographic maps. The sampling density was higher around faults and apparent and hidden intrusions, and lower in plains and lowlands.

关键词： Geochemical Heavy Minerals Varamin Promising Mineral Determination

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