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Identifying porphyry-Cu geochemical footprints using local neighborhood statistics in Baft area, Iran

Frontiers of Earth Science 2021年第1期15卷 106-120页

作者： Saeid GHASEMZADEH abbas maghsoudi Mahyar YOUSEFI Department of Mining and Metallurgical Engineering Amirkabir University of TechnologyTehran 95799-79167Iran Faculty of Engineering Malayer UniversityMalayer 65719-95863Iran

Identifying geochemical anomalies related to ore deposition processes facilitates the practice of vectoring toward undiscovered mineral deposit *** districtscale exploration studies,analysis of dispersion patterns of ore-forming elements results in more-reliable ***,deriving significant geochemical footprints and mapping the ensuing geochemical anomalies are of important issues that lead exploration geologists toward anomaly sources,e.g.,*** paper aims to examine the effectiveness of local relative enrichment index and singularity mapping technique,as two methods of local neighborhood statistics,in the delineation of anomalous areas for further exploration.A data set of element contents obtained from stream sediment samples in Baft area,Iran,therefore was applied to illustrate the procedure *** close relationship between anomalous patterns recognized and known Cu-occurrences demonstrated that the procedures proposed can efficiently model complex dispersion patterns of geochemical anomalies in the study *** results showed that singularity mapping method is a better technique,compared to local relative enrichment index,to delineate targets for follow-up exploration in the *** made this comparison because,as pointed out by exploration geochemists,dispersion patterns of geochemical indicators in stream sediments vary in different areas even for the same deposit *** variety in the dispersion patterns is due to the operation of post-mineralization subsystems,which are affected by local factors such as landscape of the areas under ***,the effectiveness of the methods should be evaluated in every area for every targeted deposit.

关键词： local neighborhood statistics robust principal component analysis singularity mapping technique local relative enrichment index exploration targets

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Gold anomaly ranking based on stream sediment geochemistry in the Fariman–Kashmar axis, NE Iran

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Acta Geochimica 2021年第2期40卷 135-149页

作者： Hassan Azmi Parviz Moarefvand abbas maghsoudi Department of Mining and Metallurgical Engineering Amir Kabir University of TechnologyTehranIran Geological Survey of Iran Northeast TerritoryMashhadIran

One of the essential tasks accelerate the decision-making process in mineral exploration projects is ranking anomalous *** this study,we used fourteen geologic maps(at scale 1:100,000)in areas where systematic geochemical explorations were conducted in the Fariman-Kashmar axis in northeast Iran to conduct the anomaly *** all these maps,samples were consistently prepared to be analyzed through statistical and geostatistical *** first,anomaly separation was carried out by fractal methods that resulted in the detection of 308 anomalous samples in 128 *** samples were classified into three groups of first,second,and thirdorder anomalies,whose number of anomalous samples were calculated based on this ranking *** factors,including the average concentration of each anomaly,its surface area,and the number of its samples,were used to rank the *** to this technique,the maximum anomaly score obtained was 172 for the Taknar area,and the minimum score was 3 for several *** validate the ranking results,some exploration operations were carried out in some of these anomalous areas in which mining operations started *** significant gold anomalous areas were introduced,which is considered an important result of this study.

关键词： Anomaly ranking Fractal model Exploration decision Gold exploration Geochemistry exploration

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Prospectivity modeling of porphyry copper deposits: recognition of efficient mono-and multi-element geochemical signatures in the Varzaghan district, NW Iran

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Acta Geochimica 2019年第1期38卷 131-144页

作者： Reza Ghezelbash abbas maghsoudi Mehrdad Daviran Faculty of Mining and Metallurgical Engineering Amirkabir University of Technology School of Mining Petroleum and Geophysics EngineeringShahrood University of Technology

The Varzaghan district at the northwestern margin of the Urumieh–Dokhtar magmatic arc, is considered a promising area for the exploration of porphyry Cu deposits in Iran. In this study we identified mono-and multi-element geochemical anomalies associated with Cu–Au–Mo–Bi mineralization in the central parts of the Varzaghan district by applying the concentration–area fractal method. After mono-element geochemical investigations, principal component analysis was applied to ten selected elements in order to acquire a multi-element geochemical signature based on the mineralization-related component. Quantitative comparisons of the obtained fractal-based populations were carried out in accordance with known Cu occurrences using Student's t-values. Then,significant mono-and multi-element geochemical layers were separately combined with related geologic and structural layers to generate prospectivity models, using the fuzzy GAMMA approach. For quantitative evaluation of the effectiveness of different geochemical signatures in final prospectivity models, a prediction-area plot was adapted. The results show that the multi-element geochemical signature of principal component one(PC1) is more effective than mono-element layers in delimiting exploration targets related to porphyry Cu deposits.

关键词： Geochemical signature Concentration–area(C–A) fractal Principal component analysis(PCA) Student’s t-value Fuzzy mineral prospectivity modeling(MPM) Prediction–area(P–A) plot

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Comparative and Competitive Adsorption of Cu（II） and Cd（II） Using Scoria： Equilibrium, Kinetic and Thermodynamic Studies

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Chemical Research in Chinese Universities 2017年第3期33卷 471-478页

作者： SEYFI Sara AZADMEHR Amir Reza maghsoudi abbas Department of Mining & Metallurgical Engineering Amirkabir University of Technology Tehran *** Iran

Heavy metals, such as Cu（Ⅱ） and Cd（Ⅱ） are among the hazardous pollutants that lead to severe ecological problems and have a toxic effect on living organisms. This study was carried out on adsorption of Cu（Ⅱ） and Cd（Ⅱ） from single-and multi-component aqueous solutions with Iranian scoria. Two- and three-parameter isotherm models, such as Langmuir, Freundlich, Temkin, Dubinin-Radushkevich, Khan and Toth have been studied for single and bi- nary adsorption of Cu（Ⅱ） and Cd（Ⅱ） onto scoria. The best result was attained from Langmuir model for Cu（Ⅱ） and Cd（Ⅱ） ions in single and binary solution. Therefore, homogenous adsorption is dominated, which was emphasized by three-parameter isotherm models. Based on the value of the free energy of adsorption for Cu（Ⅱ） and Cd（Ⅱ）, the inte-raction between these ions and scoria is a physical adsorption. In order to investigate competitive adsorption behavior, modified and extended Langmuir and Freundlich models have been studied, which indicated that adsorption of Cu（Ⅱ） and Cd（Ⅱ） on scoria has synergistic behavior. Extended Freundlich model and modified Langmuir model described Cu（Ⅱ） and Cd（Ⅱ） adsorption onto scoria, respectively.

关键词： Adsorption Individual isotherm Multi-component isotherm Kinetics Thermodynamic

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Application of K-means and PCA approaches to estimation of gold grade in Khooni district(central Iran)

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Acta Geochimica 2018年第1期37卷 102-112页

作者： Neda Mahvash Mohammadi Ardeshir Hezarkhani abbas maghsoudi Department of Mining and Metallurgical Engineering Amirkabir University of Technology

Grade estimation is an important phase of mining projects, and one that is considered a challenge due in part to the structural complexities in mineral ore *** overcome this challenge, various techniques have been used in the past. This paper introduces an approach for estimating Au ore grades within a mining deposit using k-means and principal component analysis(PCA). The Khooni district was selected as the case study. This region is interesting geologically, in part because it is considered an important gold source. The study area is situated approximately 60km northeast of the Anarak city and 270km from Esfahan. Through PCA, we sought to understand the relationship between the elements of gold,arsenic, and antimony. Then, by clustering, the behavior of these elements was investigated. One of the most famous and efficient clustering methods is k-means, based on minimizing the total Euclidean distance from each class center. Using the combined results and characteristics of the cluster centers, the gold grade was determined with a correlation coefficient of 91%. An estimation equation for gold grade was derived based on four parameters: arsenic and antimony content, and length and width of the sampling points. The results demonstrate that this approach is faster and more accurate than existing methodologies for ore grade estimation.

关键词： K-means method Clustering Principal component analysis(PCA) Estimation Gold Khooni district

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Usage of Iranian scoria for copper and cadmium removal from aqueous solutions

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Journal of Central South University 2015年第10期22卷 3760-3769页

作者： Sara Seyfi Amir Reza Azadmehr Mahdi Gharabaghi abbas maghsoudi Department of Mining & Metallurgical Engineering Amirkabir University of Technology School of Mining Engineering College of Engineering University of Tehran

The competitive removal of copper and cadmium from aqueous solutions using scoria has been investigated. Scoria was characterized by various methods, such as XRD, XRF, FT-IR and SEM. The results show that scoria sample contained augite, enstatite, diopside, and olivine. These minerals were separated from each other and each mineral was then subjected to the adsorption experiments. It was found that the main absorbent constituent in scoria was augite. Finally, statistical experimental method was used to optimization of adsorption conditions（Initial concentration of copper and cadmium ions, the amount of scoria and temperature） for removal of Cu（II） and Cd（II） ions from solution in optimum conditions. The optimum conditions are obtained as follows： concentrations of Cu（II） and Cd（II） of 400×10-6 and 554×10-6, respectively; amount of scoria of 7 g; temperature of 38 ℃. Under these conditions Cu（II） and Cd（II） ions are absorbed onto the scoria more than 79% and 16%, respectively.

关键词： scoria adsorption removal factorial design

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Experimental investigation of flow and distortion mitigation by mechanical vortex generators in a coupled serpentine inlet-turbofan engine system

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Chinese Journal of Aeronautics 2020年第5期33卷 1375-1391页

作者： Iman maghsoudi Mohammad Ali VAZIRY Mostafa MAHMOODI Department of Aerospace Malek-Ashtar University of TechnologyTehran 158751774Iran Department of Aerospace Malek-Ashtar University of TechnologyIsfahanShahinshahr 115/83145Iran

The performance of compact,aggressive ducts in advanced propulsion systems is limited by the internal flow separation coupled with the formation of secondary counter-rotating vortices that give rise to intensive flow distortions at the duct *** experimental investigation was conducted to study the flow field and passive suppression of flow separation and Aerodynamic Interface Plane (AIP) distortion in a serpentine air inlet *** were performed by a turbofan engine at several Engine Operating Points (EOPs) from 56%(idle) to 100%(max).A large total pressure deficit region arose at the upper part of the AIP,which was associated with the upper surface flow *** the new mechanical S-type vortex generators in two longitudinal positions (VGl and VG2),separation and loss were diminished at the upper part of the duct and *** VG2 arrangement attained the maximum reductions in distortion coefficients which were 73.72%,60.7% and 37.8% in DC(90°),DC(60°) and△P_C/P metrics,*** the next step of the study,some unsteady aspects of the flow field were analyzed inside the *** separation onset and reattachment points were determined by the standard deviation of static pressure on the upper *** AIP spectral distribution showed that the boundary of low pressure and high pressure recovery regions was dominated by the maximum ***,the PSD diagram of several probes at AIP revealed the vortex shedding frequency and its higher harmonics at separation *** energy content of distinct unsteady spectral features in the bare configuration was significantly reduced using VGs,which showed the improvement of flow at the duct exit.

关键词： Distortion coefficient Power spectral density Serpentine inlet Total pressure Vortex generators

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Strict Topology over the Space of Measures with Continuous Translations on a Locally Compact Foundation Semigroup

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Acta Mathematica Sinica,English Series 2011年第5期27卷 933-942页

作者： S. maghsoudi R. NASR-ISFAHANI Department of Mathematics Faculty of Sciences Zanjan University Zanjan 313 Iran Department of Mathematical Sciences Isfahan University of Technology Isfahan 84156-83111 Iran

Let δ be a locally compact semigroup, w be a weight function on δ, and Ma （δ, ω） be the weighted semigroup algebra of δ. Let L0^∞（δ; Ma（δ, ω）） be the C＊-algebra of all Ma（δ, w）-measurable functions g on δ such that g/w vanishes at infinity. We introduce and study a strict topologyβ1 （δ, ω） on Ma（δ, ω） and show that the Banach space L0^∞（6;Ma（δ, ω） can be identified with the dual of Ma（δ, ω） endowed with 31（δ, ω）. We finally investigate some properties of the locally convex topology β^1（δ, ω） on Mo（δ, ω）. Keywords Foundation semigroup, locally convex space, weighted semigroup algebra, strict topology

关键词： Foundation semigroup locally convex space weighted semigroup algebra strict topology

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Nanomechanics and Ultrastructure of Bone:A Review

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Computer Modeling in Engineering & Sciences 2020年第10期125卷 1-32页

作者： Mohammad maghsoudi-Ganjeh Xiaodu Wang Xiaowei Zeng Department of Mechanical Engineering The University of Texas at San AntonioOne UTSA CircleSan AntonioTX 78249USA

In this review,a brief presentation is first given to the hierarchical structure and mechanical behavior of ***,the recent advancements in nanoscale characterization of bone ultrastructure and ingredients are discussed based on an extensive quantity of references in the ***,computational and analytical bone mechanics at ultrastructure levels are critically reviewed with the growing body of knowledge in the *** computational and analytical models are summarized in several categories for ease of understanding bone nanomechanics and their applicability/*** review is expected to provide a well-informed foundation for the researchers interested in interrogating the complex biomechanical response of bone at its nanoscale hierarchy.

关键词： Bone ultrastructure nanoscale mechanical properties simulation and modeling strength toughness

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An experimental study on the flexural behavior of heavily steel reinforced beams with high-strength concrete

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Frontiers of Structural and Civil Engineering 2014年第1期8卷 46-56页

作者： Yasser SHARIFI Ali Akbar maghsoudi Department of Civil Engineering Vali-e-Asr University ofRafsanjan Rafsanjan Iran Department of Civil Engineering Shahid Bahonar University of Kerman Kerman Iran

In recent years, an emerging technology termed high-strength concrete （HSC） has become popular in construction industry. Present study describes an experimental research on the behavior of high-strength concrete beams in ultimate and service state. Six simply supported beams were tested, by applying comprising two symmetric concentrated loads. Tests are reported in this study on the flexural behavior of high-strength reinforced concrete （HSRC） beams made with coarse and fine aggregate together with Microsilica. Test parameter considered includes effect of being compressive reinforcement. Based on the obtained results, the behavior of such members is more deeply reviewed. Also a comparison between theoretical and experimental results is reported here. The beams were made from concrete having compressive strength of 66.81-77.72 N/mm2 and percentage reinforcement ratio （P/Pb） in the range of 0.56% - 1.20%. The ultimate moment for the tested beams was found to be in a good agreement with that of the predicted ultimate moment based on ACI 318-11, ACI 363 and C SA-04 provisions. The predicted deflection based classical formulation based on code provisions for serviceability requirements is found to underestimate the maximum deflection of HSC reinforced beams at service load.

关键词： high-strength concrete (HSC) members flexural behavior reinforced concrete experimental results ultimatemoment

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