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Geostatistics Studies and Geochemical Modeling Based on Core Data,Sheytoor Iron Deposit,Iran

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Journal of Geological Resource and Engineering 2018年第3期6卷 124-133页

作者： aref Shirazi Adel Shirazy Shahab Saki Ardeshir Hezarkhani Mining and Metallurgical Engineering Department Amirkabir University of TechnologyTehran ***Iran Faculty of Mining Petroleum and Geophysics EngineeringShahroud University of TechnologyShahrood ***Iran

In general,the purpose of the mineralization modeling is the advancement of a mineral exploration project and ultimately,the extractive design of a deposit,which is one of the most important stages in mining *** modeling is divided into two general categories,superficial and deep *** surface modeling,the aim is finding abnormal locations in terms of mineralization at the study area,which is commonly used in the early stages of exploration as one of the means for locating exploratory *** drilling in the study area with the aim of identifying mineralization and reserve estimation it is necessary to obtain deep mineralization position and its geometric features,using statistical and modeling *** mathematical,statistical and modeling methods,we can predict the position of iron mineralization in places where drilling is not done and eventually reach a three-dimensional model of the mineral materials *** a case study,the deep information about the boreholes of the sheytoor mining area in Yazd province of Iran was *** mineralization was modeled as 2D cumulative model and 3D block model,and the results were *** the geochemical threshold and the anomalous limit of iron element are calculated by concentration-volume(C-V)fractal method in this *** threshold and the anomalous limit for Fe in this deposit are 24.7%and 34.3%respectively.

关键词： Ore modeling C-V fractal method iron deposit core data sheytoor

Slope stability FEM analysis and retaining wall design:a case study of clinker in Benxi of Liaoning

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Global Geology 2008年第2期11卷 93-101页

作者： aref M.O.AL-JABALI Mohammed HAZAEA College of Construction Engineering Jilin University

Stability is always the most important problem after high slope was *** study analyzed the stress and strain inside the slope by Finite Element Method(FEM) and carried through stress distribution and failure zone,then analyzed the stability of the slope using three different methods and came to the conclusion that it is in unstable condition,so the designed retaining wall was put forward which makes the slope stable.

关键词： high slope stability FEM stress-strain analysis retaining wall

One-step random-walk process of nanoparticles in cement-based materials

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Journal of Central South University 2021年第6期28卷 1679-1691页

作者： Ali BAHARI aref SADEGHI-NIK Elena CERRO-PRADA Adel SADEGHI-NIK Mandana ROODBARI Yan ZHUGE Department of Physics University of MazandaranBabolsarIran Young Researchers and Elite Club Sari BranchIslamic Azad UniversitySariIran Department of Civil Engineering Universidad Politécnica de MadridMadridSpain Department of Civil Engineering University of South AustraliaAdelaideAustralia

Efficient modelling approaches capable of predicting the behavior and effects of nanoparticles in cement-based materials are required for conducting relevant *** the microstructural characterization of a cement-nanoparticle system,this paper investigates the potential of cell-based weighted random-walk method to establish statistically significant relationships between chemical bonding and diffusion processes of nanoparticles within cement ***_(0.5)C_(0.5)O_(3)(LSCO)nanoparticles were employed to develop a discrete event system that accounts for the behavior of individual cells where nanoparticles and cement components were expected to *** stochastic model is based on annihilation(loss)and creation(gain)of a bond in the *** model considers both chemical reactions and transport mechanism of nanoparticles from cementitious cells,along with cement hydration *** approach may be useful for simulating nanoparticle transport in complex 2D cement-based materials systems.

关键词： Markov chain Monte Carlo random-walk method Fokker-Planck equation LaSr_(0.5)C_(0.5)O_(3)(LSCO) cement nanoparticle incorporation

Nutritional Knowledge and Behavior of Professional Athletes in Khorramabad

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Journal of Life Sciences 2017年第2期11卷 65-73页

作者： Mahnaz mardani Behzad Bazgir Akram Beigi Bazgir Hossein Mansumezhad Maryam Rezapour Nutritional Health Research Center Department of Health & Nutrition Lorestan University of Medical Sciences KhorramabadIran Exercise Physiology Research Center Baqiyatallah University of Medical Science Tehran Iran Department of Health & Nutrition Lorestan University of Medical Science Iran Department of Physical Education and Sport Science Faculty of literature and Humanities Lorestan University KhorramabadIran Department of Pharmacy Arvand Branch ofAhvaz Jundishapur University of Medical Sciences Ahvaz Iran

Today it is proved that the lack of adequate nutritional knowledge leads to problems such as obesity, overweight and increased cardiovascular diseases. However, many obstacles such as poor financial support, lack of time and poor nutritional knowledge can influence achievement of optimal nutrition which is proportional to the level of the athlete＇s physical activity. The purpose of this study was to determine the level of nutritional knowledge and dietary behavior of athletes in Khorramabad in 2013. Professional athletes of Khorramabad, Iran, with more than one year of regular exercise and at least one course participating in national championships competitions were studied in this cross-sectional, descriptive-analytic study. The samples included 247 athletes aged 17-29 years. Their nutritional knowledge and behavior were measured by the nutritional knowledge and behavior inventory. Results： The results showed a significant difference in nutritional knowledge of athletes by gender and educational level; female athletes have higher nutritional knowledge than male athletes. A gender-dependent difference was found in nutritional behavior; despite their higher nutritional knowledge, female athletes have weaker nutritional behavior than male athletes. However, no significant correlation was found between BMI and nutritional knowledge and behavior of the athletes. Moreover, findings showed that nutritional knowledge and behavior could be significantly different in various sports.

关键词： Sports nutritional knowledge nutritional behavior Khorramabad.

Copper Oxide Ore Leaching Ability and Cementation Behavior, Mesgaran Deposit in IRAN

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Open Journal of Geology 2018年第9期8卷 841-858页

作者： Shayan Khakmardan aref Shirazi Adel Shirazy Hassan Hosseingholi AmirKabir University of Technology (Tehran Polytechnic) Tehran Iran Shahrood University of Technology Shahrood Iran Sormak Mining Company Tehran Iran

One of the Iranian copper deposits that is located east of Iran and also known as a primeval one in that area is Mesgaran Field. Old mining works have been clearly seen in the area. Iran is located on global copper belt and as a result it has numerous potential areas as copper deposits. The purpose of this study is identifying possible potentialities of copper mining in less developed regions of Iran with basic modern technologies. In this study, laboratory investigations of this field were done on samples via leaching and the cementation method. According to the study purposes, acid concentration, temperature, time and pulp density were selected as the main factors that were tested in leaching studies. Moreover, pH, temperature, time and the amount of iron powder were factors which were tested for copper cementation. Optimum conditions of leaching studies with 99.11% recovery rate were obtained after 120 grams per liter of H2SO4, 80 degrees Celsius, 2 hours and 100 grams per liter of solid to liquid. On the other hand, optimum conditions of cementation by iron powder were resulted at more than 95% with a pH of 3, 45 degrees Celsius, 1 hour and 1.5 times more than the stoichiometric equation of required iron powder amount to precipitate copper.

关键词： Leaching Cementation Copper Oxide Malachite VMS Copper Deposit

Minimalization of Ash from Iranian Gilsonite by Froth Flotation

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Journal of Minerals and Materials Characterization and Engineering 2021年第1期9卷 1-13页

作者： Ramona Javadi Doodran Shayan Khakmardan aref Shirazi Adel Shirazy Amirkabir University of Technology Tehran Iran Shahrood University of Technology Semnan Iran

Gilsonite is a natural, brittle, and glisten tar hydrocarbon, which widely uses in the chemical, paint, and oil industry, besides asphalt production and thermal insulation. Major gangues of Gilsonite are gypsum, pyrite, silica, dolomite, calcite, and shale which are known as ash. Due to the fine liberation degree of gangue minerals from Gilsonite, most of the physical mineral processing methods are not applicable. Gilsonite has partially a behavior like coal in flotation due to its high carbon content and the similar composition of ash. As a result, flotation is one of the best methods to decrease the ash content of Gilsonite. In this study, four factors i.e. the dosage of collector, frother, and depressant, and solid to liquid ratio in three levels were examined in flotation to reduce the ash content and increase the recovery of Gilsonite. These tests were designed with the Taguchi method by Design-Expert software. Our results showed the lowest ash content of 5.2% was obtained in the condition which 200 g/t Gasoil as collector, 100 g/t MIBC as a frother, 300 g/t sodium silicate as a depressant, and pulp density was 5% solid to liquid weight ratio.

关键词： Gilsonite Froth Flotation Taguchi Coal Ash

Optimal DG Placement in Distribution Networks Using Intelligent Systems

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Energy and Power Engineering 2012年第2期4卷 92-98页

作者： Ali aref Mohsen Davoudi Farzad Razavi Majid Davoodi Department of Electrical Engineering Hidaj Branch Islamic Azad University Hidaj Iran Department of Electrical Engineering Qazvin Branch Islamic Azad University Qazvin Iran Department of Electrical Engineering Takestan Branch Islamic Azad University Takestan Iran

Distributed Generation (DG) unlike centralized electrical generation aims to generate electrical energy on small scale as near as possible to the load centers, interchanging electric power with the network. Moreover, DGs influence distribution system parameters such as reliability, loss reduction and efficiency while they are highly dependent on their situation in the distribution network. This paper focuses on optimal placement and estimation of DG capacity for installation and takes more number of significant parameters into account compare to the previous studies which consider just a few parameters for their optimization algorithms. Using a proposed optimal Genetic Algorithm, a destination function that includes the cost parameters (such as loss reduction, fuel price, etc.) has been optimized. This method is also capable of changing the weights of each cost parameter in the destination function of the Genetic Algorithm and the matrix of coefficients in the DIGSILENT environment. It has been applied and simulated on a sample IEEE 13-bus network. The obtained results show that any change in the weight of each parameter in the destination function of the Genetic Algorithm and in the matrix of coefficients leads to a meaningful change in the location and capacity of the prospective DG in the distribution network.

关键词： Distributed Generation (DG) Distribution Network Optimization Genetic Algorithm

Utility of central venous pressure measurement in renal transplantation: Is it evidence based?

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World Journal of Transplantation 2018年第3期8卷 61-67页

作者： Ahmed aref Tariq Zayan Ajay Sharma Ahmed Halawa Department of Nephrology Sur hospital Faculty of Health and Science Institute of Learning and Teaching University of Liverpool Department of Transplantation Surgery Royal Liverpool University Hospital Department of Transplantation Surgery Sheffield Teaching Hospitals

Adequate intravenous fluid therapy is essential in renal transplant recipients to ensure a good allograft perfusion. Central venous pressure(CVP) has been cons-idered the corners-tone to guide the fluid therapy for decades; it was the only available simple tool worldwide. However, the revolutionary advances in assessing the dynamic preload variables together with the availability of new equipment to precisely measure the effect of intravenous fluids on the cardiac output had created a question mark on the future role of CVP. Des-pite the critical role of fluid therapy in the field of tra-nsplantation. There are only a few clinical studies that compared the CVP guided fluid therapy with the other modern techniques and their relation to the outcome in renal transplantation. Our work sheds some light on the available published data in renal transplantation, together with data from other disciplines evaluating the utility of central venous pressure measurement. Although lager well-designed studies are still required to consolidate the role of new techniques in the field of renal transplantation, we can confidently declare that the new techniques have the advantages of providing more accurate haemodynamic assessment, which results in a better patient outcome.

关键词： Fluid monitoring Central venous pressure Renal transplantation

Geochemical and Geostatistical Studies for Estimating Gold Grade in Tarq Prospect Area by K-Means Clustering Method

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Open Journal of Geology 2019年第6期9卷 306-326页

作者： Adel Shirazy aref Shirazi Mohammad Hossein Ferdossi Mansour Ziaii Shahrood University of Technology Shahrood Iran Young Researchers & Elite Club Shahrood Branch Islamic Azad University Shahrood Iran Amirkabir University of Technology (Tehran Polytechnic) Tehran Iran Islamic Azad University Tehran Iran

Tarq geochemical 1:100,000 Sheet is located in Isfahan province which is investigated by Iran’s Geological and Explorations Organization using stream sediment analyzes. This area has stratigraphy of Precambrian to Quaternary rocks and is located in the Central Iran zone. According to the presence of signs of gold mineralization in this area, it is necessary to identify important mineral areas in this area. Therefore, finding information is necessary about the relationship and monitoring the elements of gold, arsenic, and antimony relative to each other in this area to determine the extent of geochemical halos and to estimate the grade. Therefore, a well-known and useful K-means method is used for monitoring the elements in the present study, this is a clustering method based on minimizing the total Euclidean distances of each sample from the center of the classes which are assigned to them. In this research, the clustering quality function and the utility rate of the sample have been used in the desired cluster (S(i)) to determine the optimum number of clusters. Finally, with regard to the cluster centers and the results, the equations were used to predict the amount of the gold element based on four parameters of arsenic and antimony grade, length and width of sampling points.

关键词： Gold Tarq K-Means Clustering Method Estimation of the Elements Grade K-Means