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Acta Geologica Sinica(English Edition) 2022年第4期96卷 1246-1256页

作者： mohammad Javad SEIDY mohammad Hossein SABERI Petroleum Engineering Department Semnan UniversitySemnanIran The New Technology Campus Petroleum Engineering DepartmentSemnan UniversitySemnanIran

In a comprehensive geochemical study,the genetic relationships among 14 samples of gas condensates from the Persian Gulf were investigated for the purpose of evaluating the respective source rocks in terms of both age and sedimentary *** analysis was used for categorization and determination of a certitude range to determine the genetic type of the condensate families in the studied *** samples were collected from Late Permian-Triassic reservoirs(Dalan and Kangan formations)located in 6 gasfields(gas condensate)hosting some of Iran’s most important gas/gas condensate *** by gas chromatography-mass spectrometry(GC-MS),a total of 16 biomarker parameters(10 maturity-related parameters and 6 sedimentary environment-related parameters)were used to evaluate the samples in terms of thermal maturity(and hence their positions in the maturity chart),the sedimentary environment of the source rock and the *** of Hierarchical Clustering Analysis(HCA)and Principal Component Analysis(PCA)to the collected data led to the categorization of the samples into three main genetic groups,Ⅰ-Ⅲ.GroupsⅠandⅢwere found to be located in the east and the west of the Persian Gulf,respectively,while GroupⅡwas developed between the two other groups.

关键词： gas condensate satistical methods genetic linkage thermal maturation Persian Gulf Coastal Fars

Initial estimation of hydrate formation temperature of sweet natural gases based on new empirical correlation

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Journal of Natural Gas Chemistry 2012年第5期21卷 508-512页

作者： mohammad Mahdi Ghiasi Petroleum University of Technology Ahwaz Faculty of PetroleumPost Box:63431AhwazIran

Production,processing and transportation of natural gases can be significantly affected by clathrate *** the gas analysis is crucial to predict the right conditions for hydrate ***,Katz gas gravity method can be used for initial estimation of hydrate formation temperature （HFT） under the circumstances of indeterminate gas *** far several correlations have been proposed for gas gravity method,in which the most accurate and reliable one has belonged to bahadori and *** main objective of this study is to present a simple and yet accurate correlation for fast prediction of sweet natural gases HFT based on the fit to Katz gravity *** reviewing the error analysis results,one can discover that the new proposed correlation has the best estimation capability among the widely accepted existing correlations within the investigated range.

关键词： natural gas hydrates hydrate formation temperature gas gravity method empirical correlation

Ground-level Ozone Prediction Using Machine Learning Techniques:A Case Study in Amman,Jordan

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International Journal of Automation and computing 2020年第5期17卷 667-677页

作者： Maryam Aljanabi mohammad Shkoukani mohammad Hijjawi Faculty of Information Technology Applied Science Private UniversityAmman 11931Jordan

Air pollution is one of the most serious hazards to humans′health nowadays,it is an invisible killer that takes many human lives every *** are many pollutants existing in the atmosphere today,ozone being one of the most threatening *** can cause serious health damage such as wheezing,asthma,inflammation,and early mortality *** air pollution could be forecasted using chemical and physical models,machine learning techniques showed promising results in this area,especially artificial neural *** its importance,there has not been any research on predicting ground-level ozone in *** this paper,we build a model for predicting ozone concentration for the next day in Amman,Jordan using a mixture of meteorological and seasonal variables of the previous *** compare a multi-layer perceptron neural network(MLP),support vector regression(SVR),decision tree regression(DTR),and extreme gradient boosting(XGBoost)*** also explore the effect of applying various smoothing filters on the time-series data such as moving average,Holt-Winters smoothing and Savitzky-Golay *** find that MLP outperformed the other algorithms and that using Savitzky-Golay improved the results by 50%for coefficient of determination(R2)and 80%for root mean square error(RMSE)and mean absolute error(MAE).Another point we focus on is the variables required to predict ozone *** order to reduce the time required for prediction,we perform feature selection which greatly reduces the time by 91%as well as shrinking the number of features required for prediction to the previous day values of ozone,humidity,and *** final model scored 98.653%for R^2,1.016 ppb for RMSE and 0.800 ppb for MAE.

关键词： Ozone prediction machine learning neural networks supervised learning regression

A novel hybrid algorithm based on a harmony search and artificial bee colony for solving a portfolio optimization problem using a mean-semi variance approach

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Journal of Central South University 2016年第1期23卷 181-188页

作者： Seyed mohammad Seyedhosseini mohammad Javad Esfahani Mehdi Ghaffari Department of Industrial Engineering Iran University of Science and Technology Young Researchers and Elite Club Naragh BranchIslamic Azad University Department of Industrial Engineering Naragh BranchIslamic Azad University

Portfolio selection is one of the major capital allocation and budgeting issues in financial management, and a variety of models have been presented for optimal selection. Semi-variance is usually considered as a risk factor in drawing up an efficient frontier and the optimal portfolio. Since semi-variance offers a better estimation of the actual risk portfolio, it was used as a measure to approximate the risk of investment in this work. The optimal portfolio selection is one of the non-deterministic polynomial(NP)-hard problems that have not been presented in an exact algorithm, which can solve this problem in a polynomial time. Meta-heuristic algorithms are usually used to solve such problems. A novel hybrid harmony search and artificial bee colony algorithm and its application were introduced in order to draw efficient frontier portfolios. Computational results show that this algorithm is more successful than the harmony search method and genetic algorithm. In addition, it is more accurate in finding optimal solutions at all levels of risk and return.

关键词： portfolio optimizations mean-variance model mean semi-variance model harmony search and artificial bee colony efficient frontier

Effect of an end plate on surface pressure distributions of two swept wings

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Chinese Journal of Aeronautics 2017年第5期30卷 1631-1643页

作者： mohammad Reza SOLTANI Mehran MASDARI mohammad Rasoul TIRANDAZ Department of Aerospace Engineering Sharif University of Technology Tehran 19166Iran Faculty of New Sciences and Technologies University of Tehran Tehran Iran

A series of wind tunnel tests was conducted to examine how an end plate affects the pressure distributions of two wings with leading edge（LE） sweep angles of 23° and 40°. All the experiments were carried out at a midchord Reynolds number of 8×10～5, covering an angle of attack（AOA） range from -2° to 14°. Static pressure distribution measurements were acquired over the upper surfaces of the wings along three chordwise rows and one spanwise direction at the wing quarter-chord line. The results of the tests confirm that at a particular AOA, increasing the sweep angle causes a noticeable decrease in the upper-surface suction pressure. Furthermore, as the sweep angle increases, the development of a laminar separation bubble near the LEs of the wings takes place at higher AOAs. On the other hand, spanwise pressure measurements show that increasing the wing sweep angle results in forming a stronger vortex on the quarter-chord line which has lower sensitivity to AOA variation and remains substantially attached to the wing surface for higher AOAs than that can be achieved in the case of a lower sweep angle. In addition, data obtained indicate that installing an end plate further reinforces the spanwise flow over the wing surface, thus affecting the pressure distribution.

关键词： Chordwise Flow field Pressure distribution Swept wing Wind tunnel

Nickel doped zinc oxide nanoparticles produced by hydrothermal decomposition of nickel-doped zinc hydroxide nitrate

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Particuology 2012年第4期10卷 492-496页

作者： mohammad Yeganeh Ghotbi Nanomaterials and Nanotechnology Program Ceramic Engineering DepartmentFaculty of EngineeringMalayer UniversityMalayerIran

Zinc hydroxide nitrate, an anionic exchanger layered material, undoped as well as doped with 2-10% nickel, was synthesized by using a pH-controlled precipitation method. The layered materials were then used to produce the undoped and nickel-doped zinc oxides by hydrothermal-treatment. X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy confirmed the formation of pure phase undoped and nickel-doped layered materials, as well as the products of the hydrothermal- treated materials, nanostructured zinc oxides. Optical studies of the nanostructured zinc oxides showed a decrease in band gap with increasing content of the doping agent, nicke~.

关键词： NanostructureNickel doped zinc oxideChemical synthesisBand gap

Analysis of shear rate effects on drag reduction in turbulent channel flow with superhydrophobic wall

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Journal of Hydrodynamics 2013年第6期25卷 944-953页

作者： NOURI Nowrouz mohammad BAKHSH mohammad Saadat SEKHAVAT Setareh School of Mechanical Engineering Iran University of Science and Technology

We examined the shear rate effect on drag reduction of superhydrophobic surfaces with different slip lengths. For this purpose, turbulent channel flow was considered at the friction Reynolds numbers of Reτ = 180, 395, 500. By using Navier＇s slip condition it is shown that increasing shear rate leads to the greater reduction in drag force and also more reduction occurs in larger slip length. Based on the results, more than 25% drag reduction happens at a friction Reynolds number of Reτ= 500 for slip length of 1 ×10 5 m. The simulation results suggest that reduction in drag force occurs because slip condition reduces the Reynolds stresses, also weakens vorticity filed and the near-wall coherent structures, and therefore turbulence production is decreased.

关键词： superhydrophobic shear rate drag reduction coherent structures channel flow

Engendered nanoparticles for treatment of brain tumors

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Oncology research 2025年第1期33卷 15-26页

作者： Soroush Soleymani mohammad Doroudian Mahdieh Soezi Ali Beladi Kiarash Asgari Aso Mobarakshahi Aryana Aghaeipour Ronan Macloughlin Department of Cell and Molecular Biology School of Biological Sciences University of Leicester Leicester LE1 7RH UK. Department of Cell and Molecular Biology Faculty of Biological Sciences Kharazmi University Tehran 15719-14911 Iran. Cancer Epidemiology Research Center Aja University of Medical Sciences Tehran 14117-18541 Iran. Medical Biotechnology Research Center Aja University of Medical Sciences Tehran 14117-18541 Iran. Department of Life Sciences Faculty of Natural Sciences Imperial College London London SW7 2AZ UK. School of Pharmacy and Biomolecular Sciences Royal College of Surgeons in Ireland (RCSI) Dublin D02 YN77 Ireland. Research and Development Science and Emerging Technologies Aerogen Ltd. Galway Business Park Galway H91 HE94 Ireland. School of Pharmacy and Pharmaceutical Sciences Trinity College Dublin D02 PN40 Ireland.

Brain metastasis and primary glioblastoma multiforme represent the most common and lethal malignant brain tumors. Its median survival time is typically less than a year after diagnosis. One of the major challenges in treating these cancers is the efficiency of the transport of drugs to the central nervous system. The blood-brain barrier is cooperating with advanced stages of malignancy. The blood-brain barrier poses a significant challenge to delivering systemic medications to brain tumors. Nanodrug delivery systems have emerged as promising tools for effectively crossing this barrier. Additionally, the development of smart nanoparticles brings new hope for cancer diagnosis and treatment. These nanoparticles improve drug delivery efficiency, allowing for the creation of targeted and stimuli-responsive delivery methods. This review highlights recent advancements in nanoparticle and smart nanoparticle technologies for brain cancer treatment, exploring the range of nanoparticles under development, their applications, targeting strategies, and the latest progress in enhancing transport across the blood-brain barrier. It also addresses the ongoing challenges and potential benefits of these innovative approaches.

关键词： Blood-brain barrier (BBB) Brain cancer Nanoparticles Smart nanoparticles Stimuli responsive nanoparticles Targeted nanoparticles

Fabrication and densification enhancement of SiC-particulate-reinforced copper matrix composites prepared via the sinter-forging process

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International Journal of Minerals,Metallurgy and Materials 2014年第9期21卷 934-939页

作者： mohammadmehdi Shabani mohammad Hossein Paydar mohammad Mohsen Moshksar Department of Materials Science and Engineering School of Engineering Shiraz University

The fabrication of copper （Cu） and copper matrix silicon carbide （Cu/SiCp） particulate composites via the sinter-forging process was investigated. Sintering and sinter-forging processes were performed under an inert Ar atmosphere. The influence of sinter-forging time, temperature, and compressive stress on the relative density and hardness of the prepared samples was systematically investigated and subsequently compared with that of the samples prepared by the conventional sintering process. The relative density and hardness of the composites were enhanced when they were prepared by the sinter-forging process. The relative density values of all Cu/SiCp composite samples were observed to decrease with the increase in SiC content.

关键词： metallic matrix composites particle reinforced composites silicon carbide forging sintering bulk density

Fabrication,microstructure,and optical properties of nanocrystalline transparent LAST glass ceramics containing CeO_2

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International Journal of Minerals,Metallurgy and Materials 2014年第4期21卷 401-407页

作者： mohammad Sadegh Shakeri Materials and Energy Research Center (MERC)

In the present research, the effect of CeO2 dopant on the fabrication of transparent lithium aluminosilicate titanate （LAST） glass ceramics was investigated. Nanocrystallineβ-quartz solid solution （s.s.） was observed to be the main phase crystallized in this system. Com-parable refractive indices of the glassy matrix andβ-quartz s.s., as well as the incorporation of very fine grains size were determined as the main reasons for retaining the transparency of the glass ceramics. CeO2 was introduced as a suitable optical agent, playing a role as a network modifier in the glass ceramics, because it does not accelerate the growth process and retards the extended growth of crystals. Optical investi-gations indicate that the Fermi energy level, direct and indirect band gaps, and Urbach energy decrease with increasing nanocrystal content in the glassy matrix of specimens, which can be related to the expansion of conduction band, the enhancement of ionic bonds in the crystal lat-tice, and the enhancement of structural arrangement degree, respectively.

关键词： glass ceramics nanocrystals alurninosilicates titanates transparency optical properties