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Discrimination geochemical interaction effects on mineralization at the polymetallic Glojeh deposit,NW Iran by interative backward quadratic modeling

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Acta Geochimica 2020年第2期39卷 236-254页

作者： farshad darabi-golestan Ardeshir Hezarkhani Department of Mining and Metallurgical Engineering Amirkabir University of Technology424 Hafez AveTehran 15875-4413Iran

The physico-chemical exchanges between hydrothermal fluids and the host rock are usually controlled by elemental interaction effects.A criterion-based backward elimination approach applies the iterative regression analysis and analysis of variance to investigate the geochemical features of the polymetallic Glojeh(Au-Ag-CuPb-Zn)deposit in NW Iran.A statistical definition of the elemental interaction effects(X(i-j)^2,Xi×Xj)could elucidate the relationship between variables and the performance of a full quadratic polynomial model(QPM).The model optimization procedure was carried out by the removal of insignificant predictors(P value 95%CL)based on R^2(pred.)*** order to straighten the convergent trend with R^2 and R^2(adj.),R^2(pred.)gradually increased from 0%to 77.8%by 15-steps *** miniature-scale geochemical changes indicate double ordinal Au(Ag,Pb)and Au(Ag,Zn)interactions within the vein and host rock,in *** show that the Au(Pb-Zn)commonly presents ordinal effect at the vein and disordinal interaction at the host *** ordinal-disordinal interaction revealed that elements Pb and Zn have similar geochemical features during *** addition,Akima's polynomial contour map confirms the results from Pb-Zn interaction effects by dependency tracing between Au-Pb-Zn at different ***,it is noteworthy that Pb and Zn occur together in the second phase of Pb-Zn-Cu±(Ag±Cd)sulfide mineralization at Glojeh,which implies intergrowth and interaction of Pb-Zn on Au *** and Zn demonstrate relatively high mobility and are generally concentrated in the near surface *** is an immobile element during alteration and high content Hg zone is mainly restricted to narrow stripes above ore vein and veinlets.

关键词： Backward Elimination Quadratic polynomial model Miniature-scale changes Ordinal–disordinal interaction effect Akima's polynomial contour map Immobile element

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Lateral Dispersion Pattern of Main Indicators at the Glojeh Polymetallic Deposit,NW Iran

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Journal of Metallic Material Research 2019年第1期2卷 30-38页

作者： farshad darabi-golestan ,Ardeshir Hezarkhani Department of Mining and Metallurgical Engineering Amirkabir University of Technology.424 Hafez AveTehranIran

The criterion-base iterative stepwise Backward Elimination(BE)method was used to predict Au according to the main variables(Ag,Cu,Pb,and Zn).The optimization process of the quadratic polynomial model are carried out on different ***,Pb and Zn with Ag×Zn and Pb×Zn are significant to determine the lateral dispersion of *** means Zn is the predominant element in near surface ***,it point out that the polymetallic(Au-Ag-Cu-Pb-Zn)high-sulfidation hydrothermal veins may be related to a porphyry deposit at ***,2D surface contour maps using kriging confirms all the results of the dispersion pattern of elements at Glojeh.

关键词： Iterative stepwise regression Interaction effects Lateral zonation Linear productivity Kriging technique

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Interpretation of Water Samples by Correspondence Analysis for Radioactive Elements in the Northern Coast of Oman Sea

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Journal of Metallic Material Research 2022年第1期5卷 25-31页

作者： farshad darabi-golestan Mohamad Reza Zare Department of Mining and Metallurgical Engineering Amirkabir University of TechnologyTehranIran Department of Physics Faculty of SciencesUniversity of IsfahanIsfahan81746-73441Iran

Oman Sea is connecting belt between the Indian Ocean and Persian *** it strategic and environmental aim,presence of natural radionuclide ^(226)Ra,^(232)Th,^(40)K and ^(137)Cs as man-made element is *** samples were taken from 36 marine spots at the coastal strip from Hormoz canyon to Goatr seaport in the northern coast of Oman *** analysis is used to identify variation and relationship between samples(Q-mood analysis)and variable(R-mood analysis)based on approximate χ^(2)*** elements(^(226)Ra,^(232)Th and^( 40)K),physical(temperature,pH,turbidity,conductivity,special density)and chemical(salinity,oxygen and chlorophyll)parameters of water for 36 samples handled by correspondence analysis,there are two outstanding result,(1)Radioactive elements show high correlation in factors by greater eigenvalue,and (2)some of the samples such as W13,W24 and rather W02,W05 and W12 show highest activity from Radioactive elements and also temperature and conductivity show nearest relation with them in many factors.

关键词： Hormoz canyon R-mood analysis Correspondence analysis Radioactive elements Marine spot samples

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Quadratic investigation of geochemical distribution by backward elimination approach at Glojeh epithermal Au(Ag)-polymetallic mineralization, NW Iran

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Journal of Central South University 2018年第2期25卷 342-356页

作者： darabi-golestan farshad Hezarkhani Ardeshir Department of Mining and Metallurgical Engineering Amirkabir University of Technology

The correspondence analysis will describe elemental association accompanying an indicator *** analysis indicates strong mineralization of Ag,As,Pb,Te,Mo,Au,Zn and to a lesser extent S,W,Cu at Glojeh polymetallic mineralization,NW *** work proposes a backward elimination approach(BEA)that quantitatively predicts the Au concentration from main effects(X),quadratic terms(X2)and the first order interaction(Xi×Xj)of Ag,Cu,Pb,and Zn by initialization,order reduction and validation of *** is done based on the quadratic model(QM),and it was eliminated to reduced quadratic model(RQM)by removing insignificant *** the QM optimization process,overall convergence trend of R2,R2(adj)and R2(pred)is obvious,corresponding to increase in the R2(pred)and decrease of *** RQM consisted of(threshold value,Cu,Ag×Cu,Pb×Zn,and Ag2-Pb2)and(Pb,Ag×Cu,Ag×Pb,Cu×Zn,Pb×Zn,and Ag2)as main predictors of optimized model according to288and679litho-samples in trenches and boreholes,*** to the strong genetic effects with Au mineralization,Pb,Ag2,and Ag×Pb are important predictors in boreholes RQM,while the threshold value is known as an important predictor in the trenches *** RQMs R2(pred)equal74.90%and60.62%which are verified by R2equal to73.9%and60.9%in the trenches and boreholes validation group,respectively.

关键词： correspondence analysis first order interaction reduced quadratic model (RQM) optimized model order reduction and validation strong genetic effects

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Charge structure factors of doped armchair nanotubes in the presence of electron-phonon interaction

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Chinese Physics B 2020年第9期29卷 415-422页

作者： Hamed Rezania farshad Azizi Department of Physics Razi UniversityKermanshahIran

We present the behaviors of both dynamical and static charge susceptibilities of doped armchair nanotubes using the Green function approach in the context of Holstein-model ***,the effects of magnetization and gap parameter on the the plasmon modes of armchair nanotube are investigated via calculating correlation function of charge density *** phase approximation has been implemented to find the interacting dynamical charge *** electrons in this systems interacts with each other by mediation of dispersionless Holstein *** results show that the increase of gap parameter leads to decreasing intensity of charge collective *** the frequency position of the collective mode tends to higher frequencies due to the gap *** the number of collective excitation mode decreases with chemical potential in the presence of electron-phonon *** the temperature dependence of static charge structure factor of armchair nanotubes is *** effects of the gap parameter,magnetization and electron-phonon interaction on the static structure factor are addressed in details.

关键词： armchair nanotube Green's function

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Effect of methane content and the oscillating electric field between electrodes on atmospheric Ar/methane plasma jet and DLC coating deposition

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Plasma Science and Technology 2020年第8期22卷 76-89页

作者： Reza SAFARI farshad SOHBATZADEH Department of Atomic and Molecular Physics Faculty of Basic SciencesUniversity of MazandaranBabolsar 47416Iran

In this work,the effects of the methane gas flow and the internal oscillating electric field between electrodes on radio-frequency(RF)atmospheric pressure argon/methane plasma jet and process of diamond-like carbon(DLC)film deposition have been *** of RF atmospheric Ar/methane plasma jet such as active species density,length,electron temperature,appearance and ionization process of argon/methane plasma jet are changed due to the changing of methane flow content and electric field vector and its *** increasing methane flow,the formation of C2 hydrocarbon and CH band content is decreased because injected electrical energy to a mixture of Ar/methane gases is insufficient to stabilize the ionization process of methane gas and the electrical-chemical reaction rate is *** shortening the gas gap between two electrodes,electric field strength and its gradient are increased leading to more energy injection to the ***-chemical reactions are strengthened leading to increasing the CH band *** phenomena introduce the Ar/methane plasma jet in different modes causing to deposit the DLC film with different structures and *** using quartz glass and alumina ceramic as dielectric barriers tubes,RF atmospheric pressure Ar/methane plasma jet has been used to deposit DLC coating in different *** methane content and shortening the gas gap leads to decreasing sp3 bonded content and the quality of the deposited film.

关键词： RF atmospheric plasma methane flow electric field

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Core designing of a new type of TVS-2M FAs:neutronics and thermal-hydraulics design basis limits

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Frontiers in Energy 2021年第1期15卷 256-278页

作者： Saeed GHAEMI farshad FAGHIHI Department of Nuclear Engineering School of Mechanical EngineeringShiraz UniversityShiraz 71936-16548Iran Radiation Research Center Shiraz UniversityShiraz 71936Iran Lonizing and Non-Ionizing Radiation Center Shiraz University of Medical ScienceShirazIran

One of the most important aims of this study is to improve the core of the current VVER reactors to achieve more burn-up(or more cycle length)and more intrinsic *** is an independent study on the Russian new proposed FAs,called TVS-2M,which would be applied for the future advanced *** important aspects of neutronics as well as thermal hydraulics investigations(and analysis)of the new type of Fas are conducted,and results are compared with the standards PWR *** TVS-2M FA contains gadolinium-oxide which is mixed with UO_(2)(for different Gd densities and U-235 enrichments which are given herein),but the core does not contain *** new type TVS-2M Fas are modeled by the SARCS software package to find the PMAXS format for three states of CZP and HZP as well as HFP,and then the whole core is simulated by the PARCS code to investigate transient *** addition,the WIMS-D5 code is suggested for steady core modeling including TVS-2M FAs and/or TVS *** neutronics aspects such as the first cycle length(first cycle burn up in terms of MWthd/kgU),the critical concentration of boric acid at the BOC as well as the cycle length,the axial,and radial power peaking factors,differential and integral worthy of the most reactive CPS-CRs,reactivity coefficients of the fuel,moderator,boric acid,and the under-moderation estimation of the core are conducted and benchmarked with the PWR ***,the burn-up calculations indicate that the 45.6 d increase of the first cycle length(which corresponds to 1.18 MWthd/kgU increase of burnup)is the best improving aim of the new FA type called ***,thermal-hydraulics core design criteria such as MDNBR(based on W3 correlation)and the maximum of fuel and clad temperatures(radially and axially),are investigated,and discussed based on the CDBL.

关键词： TVS-2M FAs core design basis limits VVER-1000 analysis mixture of uranium-gadolinium oxides fuels thermal-hydraulics PARCS WIMS-D5

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Economic analysis on log damage during logging operation in Caspian Forests

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Journal of Forestry Research 2013年第3期24卷 585-589页

作者： farshad Keivan Behjou Faculty of Agriculture University of Mohaghegh ArdabiliArdabil Iran P.O.Box:56199-11367

Waste wood was studied in an economic enterprise by logging, function, tree species and log size in four Caspian hardwood sites. Dam- aged logs were recorded with additional information obtained for the location, dimensions and type of damage. The data were analyzed statis- tically to determine significant differences of damage during logging process. The results indicated that animal harvesting systems cause more volume （40.5% of log volume） and value loss （89.5 $.m^-3） to logs than mechanized harvesting systems （13.9% and 6.0 $.m^-3）, also bucking resulted in significantly more volume （9.9% of log volume） and value loss （5.5 $.m-3） when compared to skidding （0.2% of log volume and 0.2 $.m^-3）, decking （0.4% of log volume and 0.2 $.m^-3） and loading （0.2% of log＇s volume and 0.3 $.m^-3） operations. Study showed that the processes of skidding, decking and loading of logs have very little impact on dam- age levels. Volume and value losses of damaged logs are not sensitive to tree species and log size. The information from the field study is impor- tant in creating new guidelines or training to help minimize hardwood log damage during the timber harvesting process.

关键词： log damage forest operations Caspian hardwood forests

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Optimally Connected Hybrid Complex Networks with Windmill Graphs Backbone

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Journal of Systems Science & Complexity 2020年第4期33卷 903-929页

作者： SAFAEI farshad BABAEI Amin MOUDI Mehrnaz Faculty of Computer Science and Engineering Shahid Beheshti UniversityTehranIran School of Computer Science Institute for Research in Fundamental SciencesTehranIran Department of Computer Engineering University of Torbat HeydariehTorbat HeydariehIran

The significance of the existing analysis methods in complex networks and easy access to the ever-increasing volume of information present the emergence of proposing new methods in various fields based on complex system ideas. However, these systems are usually faced with various random failures and intelligent attacks. Due to the nature of the components’ behaviors, the occurrence of the failures and faults in their operations and the alteration of their topologies are the most important problems. Since the complex systems are usually used as the infrastructures of other networks, their robustness against failures and the adoption of suitable precautions are necessary. Moreover, the smallworld effect in most complex systems is one of the crucial structural features. The authors found that the relation between these two is not well-known and may even be in conflict in some networks. The main goal in this paper is to achieve an optimal topology by utilizing a robustness-oriented multiobjective trade-off optimization model(edge rewiring) to establish a peaceful relationship between the two requirements. By offering a proposed rewiring method with the small-world effect, which is called core-periphery Windmill property, the authors demonstrated that the generated networks are able to exhibit appropriate robustness even during intelligent attacks. The results obtained in terms of Windmill graphs are presented very good approximations to demonstrate the small-world effect. These graphs are used as the initial core in the construction of the optimized networks’ topologies.

关键词： effect. utilizing Optimal

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Evaluation of soil erodibility factor(k)for loess derived landforms of Kechik watershed in golestan Province,North of Iran

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Journal of Mountain Science 2016年第11期13卷 2028-2035页

作者： farshad KIANI Aboutaleb GHEZELSEFLO Dept.of Soil Science Gorgan university of agricultural sciences and natural resourcesGorgan ***Iran Natural resources organization of golestan province Gorgan ***Iran

The technique proposed by Wischmeier ＆ Smith for estimating the soil erodibility factor is among the most important methods in this regard. Given the high amounts of silt and lime content in loess soils of eastern parts of golestan province in Iran, this study aims to evaluate the ability of Wischmeier ＆ Smith index to estimate the soil erodibility of this region. Soil erodibility was first obtained by Wischmeier nomograph and then was compared with the actual values obtained by selecting six plots and then performing physical and chemical tests on these samples. Using the nomograph, Wischmeier index was calculated to be about 0.05-0.092 Mg h MJ？1 mm？1. The results showed that Wischmeier index was 182, 4.11, 6 and 0.35 times than actual value in field with half-hour rainfall, Fournier index, SWAT value with half-hour rainfall and SWAT value with Fournier index, respectively. Obtained results showed that erodibility estimated by Wischmeier ＆ Smith index was higher than the actual measured value. Poor performance of this index in loess soils indicates the need for further research in this field.

关键词： Soil erodibility Loess Wischmeier nomograph Iran

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