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Journal of Central South University 2016年第8期23卷 1839-1846页

作者： seyyed mostafa tahsini Ayyub Halvaee Hamed Khosravi School of Metallurgy and Materials Engineering College of Engineering University of Tehran Department of Materials Engineering Faculty of Engineering University of Sistan and Baluchestan

Similar friction welded joints of AA-7005 aluminum rods were fabricated using different combinations of process parameters such as friction pressure(1.0, 1.5 and 2.0 MPa) and friction time(10, 15 and 20 s). Interfacial microstructure and formation of intermetallic compounds at the joint interface were evaluated via scanning electron microscopy(SEM) equipped with energy dispersive spectrum(EDS), and optical microscopy(OM). Microstructural observations reveal the formation of intermetallic phases during the welding process which cannot be extruded from the interface. Theses phases influence the tensile strength of the resultant joints. From the tensile characteristics viewpoint, the greatest tensile strength value of 365 MPa is obtained at 1.5 MPa and 15 s. Finally, the role of microstructural features on tensile strength of resultant joints is discussed.

关键词： friction welding AA-7005 aluminum alloy microstructure intermetallics tensile strength

Coupled hydroelastic vibrations of an elliptical cylindrical tank with an elastic bottom

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Journal of Hydrodynamics 2014年第2期26卷 264-276页

作者： HASHEMINEJAD seyyed M. TAFANI mostafa Acoustics Research Laboratory Center of Excellence in Experimental Solid Mechanics and Dynamics School of Mechanical Engineering Iran University of Science and Technology

An exact three-dimensional analysis based on the linear potential theory and the elaborated method of eigenfunction expansion in elliptic coordinates are presented to study the free coupled elasto-hyrodynamic characteristics of an upright non-deformable cylindrical container of elliptical planform with a flexible bottom plate, filled to an arbitrary depth with an inviscid incompressible liquid. Extensive numerical data are presented in an orderly fashion for the first few symmetric/anti-symmetric coupled hydroelastic natural frequencies as a function of fluid depth parameter for two plate aspect ratios. Also, selected hydrodynamic and structural deformation modes shapes are presented in graphical form. The effects of liquid level, bottom plate elasticity, and cross sectional aspect ratio on the sloshing frequencies and hydrodynamic pressure modes are examined. The validity of the results is examined through computations using a commercial finite element package as well as by comparison with the data available in literature.

关键词： exact solution fluid-structure interaction free surface oscillations vertical elliptical vessel Mathieu functions

A method for extracting anomaly map of Au and As using combination of U-statistic and Euclidean distance methods in Susanvar district,Iran

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Journal of Central South University 2017年第11期24卷 2693-2704页

作者： seyyed Saeed Ghannadpour Ardeshir Hezarkhani mostafa Sharifzadeh Department of Mining & Metallurgical Engineering Amirkabir University of Technology (Tehran Polytechnic) Department of Mining Engineering and Metallurgical Engineering Western Australia School of MineCurtin University

Quantitative descriptions of geochemical patterns and providing geochemical anomaly map are important in applied geochemistry. Several statistical methodologies are presented in order to identify and separate geochemical anomalies. The U-statistic method is one of the most important structural methods and is a kind of weighted mean that surrounding points of samples are considered in U value determination. However, it is able to separate the different anomalies based on only one variable. The main aim of the presented study is development of this method in a multivariate mode. For this purpose, U-statistic method should be combined with a multivariate method which devotes a new value to each sample based on several variables. Therefore, at the first step, the optimum p is calculated in p-norm distance and then U-statistic method is applied on p-norm distance values of the samples because p-norm distance is calculated based on several variables. This method is a combination of efficient U-statistic method and p-norm distance and is used for the first time in this research. Results show that p-norm distance of p=2(Euclidean distance) in the case of a fact that Au and As can be considered optimized p-norm distance with the lowest error. The samples indicated by the combination of these methods as anomalous are more regular, less dispersed and more accurate than using just the U-statistic or other nonstructural methods such as Mahalanobis distance. Also it was observed that the combination results are closely associated with the defined Au ore indication within the studied area. Finally, univariate and bivariate geochemical anomaly maps are provided for Au and As, which have been respectively prepared using U-statistic and its combination with Euclidean distance method.

关键词： mineral anomaly Susanvar district U-statistic method Euclidean distance bivariate anomaly map

Wettability alteration and oil recovery by spontaneous imbibition of smart water and surfactants into carbonates

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Petroleum Science 2020年第3期17卷 712-721页

作者： Saeb Ahmadi mostafa Hosseini Ebrahim Tangestani seyyed Ebrahim Mousavi Mohammad Niazi Department of Chemical Engineering Sanandaj Branch Islamic Azad UniversitySanandajIran Department of Petroleum Engineering Faculty of Chemical EngineeringTarbiat Modares UniversityTehranIran Faculty of Chemical Engineering Tarbiat Modares UniversityTehranIran

Naturally fractured carbonate reservoirs have very low oil recovery efficiency owing to their wettability and tightness of ***,smart water can enhance oil recovery by changing the wettability of the carbonate rock surface from oilwet to water-wet,and the addition of surfactants can also change surface *** the present study,the effects of a solution of modified seawater with some surfactants,namely C12 TAB,SDS,and TritonX-100(TX-100),on the wettability of carbonate rock were investigated through contact angle *** recovery was studied using spontaneous imbibition tests at 25,70,and 90°C,followed by thermal gravity analysis to measure the amount of adsorbed material on the carbonate *** results indicated that Ca2+,Mg2+,and SO42-.ions may alter the carbonate rock wettability from oil-wet to water-wet,with further water wettability obtained at higher concentrations of the ions in modified *** of NaCl from the imbibing fluid resulted in a reduced contact angle and significantly enhanced oil *** oil recoveries were obtained with modified seawater at 25 and 70°C,but once the temperature was increased to 90°C,the oil recovery in the spontaneous imbibition experiment increased *** of smart water with C12 TAB surfactant at 0.1 wt%changed the contact angle from 161°to 52°and enhanced oil recovery to 72%,while the presence of the anionic surfactant SDS at 0.1 wt%in the smart water increased oil recovery to 64.5%.The TGA analysis results indicated that the adsorbed materials on the carbonate surface were minimal for the solution containing seawater with C12 TAB at 0.1 wt%(SW+CTAB(0.1 wt%)).Based on the experimental results,a mechanism was proposed for wettability alteration of carbonate rocks using smart water with SDS and C12 TAB surfactants.

关键词： Smart water Surfactants Carbonate rock Wettability alteration

The positive effects of Mediterranean-neutropenic diet on nutritional status of acute myeloid leukemia patients under chemotherapy

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Frontiers in Biology 2018年第6期13卷 475-480页

作者： Jalali seyyed mostafa Morteza Abdollahi Atiyeh Hosseini Dehghani Karl Bozorg Ajami Marjan Azadeh Kimia Moiniafshar 7th Floor Bldg No.2SBUMSArabi AveDaneshjoo BlvdVelenjakTehranTehran 19839-63113Iran

Introduction Cancer and chemotherapy-induced malnutrition increase death, reduce the response to treatment, and increase multiple kinds of side effects. The aim of this study was to investigate the effects of Mediterranean-neutropenic diet on the nutritional status of acute myeloid leukemia patients under *** and Methods 50 patients were divided into two groups by a random allocation scheme: the Mediterranean-neutropenic diet (n = 25) and the neutropenic diet group (n = 25). The intervention was implemented during a one month period. The nutritional status was evaluated based on PG-SGA. Serum albumin levels and dietary intake were also *** After the intervention, the mean serum albumin level in the intervention group was significantly higher than the beginning of the study (p = 0.09) and in comparison with the control group (p = 0.01). Also, the mean serum albumin level in the control group significantly decreased at the end of the study compared to the beginning of the study (p = 0.03). After intervention, the nutritional status of the patients in the intervention group was significantly improved compared to the control *** In general, based on the results of this study, the Mediterranean neutropenic diet improves nutritional status during chemotherapy by increasing food intake, preventing weight loss and increasing serum albumin levels

关键词： nutritional status Mediterranean diet neutropenic diet AML chemotherapy

The Effect of the Family’s Socioeconomic Factors on Nutrition of Elementary School Children

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Health 2014年第19期6卷 2657-2667页

作者： Fereshteh Farzianpour Ali Reihani seyyed mostafa Hosseini Halea Saderzadeh Yaganeh Seyead Shahab Hosseini Department of Health Management and Economics School of Public Health Tehran University of Medical Sciences Tehran Iran Department of Epidemiology and Statistics School of Public Health Tehran University of Medical Sciences Tehran Iran Department of Nutrition School of Public Health Tehran University of Medical Sciences Tehran Iran Tehran University Tehran Iran

Introduction: Anthropometric indices are used for assessing the nutrition status of people and societies. The indices determine the growth of the child’s nutrition status, his socioeconomic status and his quality of life. This research aims to study the anthropometric indices of elementary school children in the Iranian city of Piranshahr using the Body Mass Index (BMI) and waist circumference in the first six months of 2011. Methods: In this descriptive-analytical cross-sectional study, 1803 students aged between 7 and 11 in Piranshahr were studied. Multi-stage cluster sampling was used. The research setting was an elementary school in Piranshahr. Demographic data were collected through interviews and record in questionnaires. A Secca stadiometer was used to measure the height of each student standing without shoes (accuracy of 0.1 centimeter). The weight was measured using a spring scale with an accuracy of 0.1 kilogram with the least possible clothes on. The weight was divided by the square of height (square meter) to calculate BMI. To determine overweight and obesity, BMI percentiles of Center for Disease Control (CDC) were used. In order to use appropriate tests, the normality and equality of variances were measured by Leven and K-S tests, respectively. Results: The study found that 231 children (12.8%) were at risk of overweight and 96 children (5.3%) were overweight. Conclusion: There was a meaningful difference between boys and girls in terms of nutrition status of BMI, father’s higher education level, shortness, abdominal obesity and family history of obesity, and father’s jobs

关键词： Anthropometric Socioeconomic Factors Nutrition Status Elementary School Children Piranshahr Iran