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Chinese Chemical Letters 2011年第8期22卷 927-930页

作者： ebrahim Soleimani Mohammad Mehdi Khodaei Afsaneh Taheri Kal Koshvandi Department of Chemistry Razi UniversityKermanshah 67149Iran

An efficient method for the synthesis of 14-alkyl or aryl 14H-dibenzo[a,j]xanthene derivatives by the reaction of β-naphthol,and aldehydes in the presence of a catalytic amount of bismuth（Ⅲ） chloride（BiCl_3） under solvent-free conditions at 110℃is *** and aromatic aldehydes were used in the reaction and in all cases the desired products were synthesized *** reaction was studied under different temperatures;the maximum yield was obtained in a short reaction period at 110℃.The method offers the advantages of high yields,short reaction times,simplicity and easy workup compared to the conventional method of syntheses.

关键词： Bismuth(Ⅲ) chloride 14H-Dibenzo[a j]xanthenes β-Naphthol

The impact of land afforestation on carbon stocks surrounding Tehran,Iran

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Journal of Forestry Research 2014年第1期25卷 135-141页

作者： Saeid Varamesh Seyyed Mohsen Hosseini Farshad Keivan Behjou ebrahim Fataei Department of Forestry Faculty of Natural ResourcesTarbiat Modares University Department of Environmental engineering Ardabil BranchIslamic Azad University Faculty of Agricultural Technology and Natural Resources University of Mohaghegh Ardabili

The city of Tehran, like many polluted metropolises of the world, has higher emissions of greenhouse gases than other cities in Iran, due to heavy consumption of fossil fuel and landuse changes. To estimate carbon sequestration in two 40 year-old stands of plantedCupressus arizonica andFraxinus rotundifolia in degraded lands surrounding Tehran , sampling of above- and below- ground biomass, soil （at two depths of 0-15 and 15-30 cm）, and leaf litter was done by systematic random sampling. The total carbon stocks ofC. arizonica and F. rotundifolia stands were respectively 328.20 and 150.69 Mg·ha-1. The aboveground biomass with 233.16（71%） Mg·ha-1 inC. arizonica and 88.16 （58.50%） Mg·ha-1 inF. rotundifolia contributed the most shares to carbon sequestration. The diameter at breast height, total height, basal area, total volume, and biomass ofC. arizonica were significantly （p 〈0.01） higher than those ofF. rotundifolia. Also the depth of 0-30 cm of soil contributed between 18.29 % and 32.15 % of total ecosystem carbon, respectively. The economic value of carbon sequestration in the two stands in 2011 was calculated at 3.5 and 2.5 million dollars, respectively. Our results indicate that afforestation of the degraded land surrounding Tehran would sequester more carbon than would continuously degraded land, the current status quo. These stands can absorb atmospheric CO2at different rates, thus tree species selection and stand development should be considered in planning future afforestation projects.

关键词： carbon sequestration afforestation Cupressus arizonica Fraxinus rotundifolia Tehran.

A Unified Computational Method for Simulating Dynamic Behavior of Planing Vessels

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China Ocean Engineering 2009年第3期23卷 517-528页

作者： Mohammad Saeed SEIF ebrahim JAHANBAKHSH Roozbeh PANAHI Mohammad Hossein KARIMI Sharif University of Technology Transportation Research Institute

High speed planing hulls have complex hydrodynamic behaviors. The trim angle and drafts are very sensitive to speed and location of the center of gravity. Therefore, motion simulation for such vessels needs a strong coupling between rigid body motions and hydrodynamic analysis. In addition, free surface should be predicted with good accuracy for each time step. In this paper, velocity and pressure fields are coupled by use of the fractional step method. On the basis of in- tegration of the two-phase viscous flow induced stresses over the hull, acting loads （forces and moments） are calculated. With the strategy of boundary-fitted body-attached mesh and calculation of 6-DoF motions in each time step, time history of ship motions including displacements, speeds and accelerations are evaluated. For the demonstration of the software capabilities, circular cylinder slamming is simulated as a simple type of water slamming. Then, a high-speed planing catamaran is investigated in the case of steady forward motion. All of the results are in good concordance with experimental data. The present method can be widely implemented in design as well as in the performance prediction of high-speed vessels.

关键词： ship motions slamming planing vessel

Temperature profile estimation:A study on the Boberg and Lantz steam stimulation model

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Petroleum 2020年第1期6卷 92-97页

作者： Mehdi Safari Raoof Gholami ebrahim Khajehvandi Majid Mohammadi Department of Petroleum Engineering Curtin UniversityMalaysia Department of Petroleum Engineering Amirkabir University of Technology(Tehran Polytechnic)TehranIran Department of Energy Engineering Faculty of ScienceQom University of TechnologyQomIran

Cyclic steam stimulation(CSS)is widely used for production from heavy oil reservoirs where oil viscosity is manipulated by *** analytical models have been developed to predict the temperature evolution in the reservoir and estimate the oil ***,they often suffer from a number of assumptions which ultimately reduce their efficiency in providing a realistic *** this study,a numerical solution was proposed for two-dimensional heat conduction in heavy oil reservoirs to obtain the temperature evolution during the soaking *** a better comparison,an industry widely accepted analytical model,knows as the Boberg and Lantz steam stimulation model,together with its modified version later proposed by Bensten and Donohue were considered to examine temperature changes in a synthetic case *** results obtained indicated that the analytical solutions overestimate the average temperature of the reservoir by 42%after 300 days of injection while the numerical formulation can provide a close *** numerical approach could be a useful tool to estimate the temperature and oil production from heavy oil reservoirs.

关键词： Thermal EOR Steam stimulation Finite element Boberg and Lantz model Temperature prediction

Relationship between CD14-159C/T gene polymorphism and acute brucellosis risk

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Asian Pacific Journal of Tropical Medicine 2016年第3期9卷 241-245页

作者： Mehdi Moghadampour ebrahim Eskandari-Nasab Fatemeh Shabani Department of Microbiology School of MedicineZahedan University of Medical Sciences Infectious Diseases and Tropical Medicine Research Center.Zahedan University of Medical Sciences Department of Clinical Biochemistry School of Medicine.Zahedan University of Medical Sciences Genetic of Non-Communicable Disease Research Center Zahedan University of Medical Sciences School of Medicine Jiroft University of Medical Sciences

Objective:To investigate the association between the cluster of differentiation 14(CD14)-I59C/T(rs2569190) gene polymorphism and susceptibility to acute brucellosis in an Iranian ***:The study included 153 Iranian patients with active brucellosis and 128 healthy individuals as the control *** of the CD 14 variant was performed using an amplification refractory mutation system-polymerase chain reaction ***:The prevalence of CD14-159 TT and CT genotypes were associated with increased risk of brucellosis[odds ratio(OR)=l.993.95%confidence interval(95%CD=1.07-3.71.P=0.03 for CT:OR=3.869.95%CI= 1.91-7.84,P=0.01 for TT ***,the minor allele(T) was significantly more frequently present in brucellosis patients than in controls(61%vs.45%.respectively),and was a risk factor for brucellosis(OR=3.058.95%CI= 1.507-6.315.P=0.01).Condusions:The findings provid suggestive evidence of association of the CDI4-159C/T gene polymorphism with susceptibility to acute brucellosis in the Iranian population.

关键词： Acute brucellosis Cluster of differentiation 14 Single nucleotide polymorphism

Influence of catalyst on structural and morphological properties of TiO2 nanostructured films prepared by sol-gel on glass

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Progress in Natural Science:Materials International 2013年第1期23卷 77-84页

作者： Mehdi Alzamani Ali Shokuhfar ebrahim Eghdam Sadegh Mastali Mechanical Department Advanced Materials and Nanotechnology Research LabK.N.Toosi University of Technology Faculty of Metallurgical and Materials Engineering Semnan University

Transparent TiO2 thin films have been prepared by the sol-gel method using titanium alkoxides as *** films were deposited on glass supports by the dip-coating *** TiO2 layer acts as a self-cleaning coating generated from its photocatalysis and photoinduced *** crystalline structure of TiO2 films was dominantly identified as the anatase phase,consisted of uniform spherical particles of about 14-50 nm in size,which strongly depends upon catalyst-type and heat treatment *** heat treating temperature can lead to an increase in crystalline *** results indicated that the sample S.S(sample derived from sol containing sulfuric acid as catalyst) exhibits superhydrophilic nature and better photocatalytic activity,which can be attributed to its higher anatase content and lower crystalline *** studies,carried out using Atomic Force Microscopy(AFM),confirm the presence of crystalline phase with such a grain size and low surface ***,the applied films exhibiting high photocatalytic activity,superhydrophilic behavior,and low surface roughness can be used as an efficient self-cleaning coating on glass and other optical applications.

关键词： TiO2 films Structural properties Superhydrophilicity Glass substrate

A numerical study on heat transfer enhancement and design of a heat exchanger with porous media in continuous hydrothermal flow synthesis system

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Chinese Journal of Chemical Engineering 2017年第10期25卷 1352-1359页

作者： Pedram Karimi Pour-Fard ebrahim Afshari Masoud Ziaei-Rad Shahed Taghian-Dehaghani Department of Mechanical Engineering Faculty of Engneering University of Isfahan Hezar Jerib Ave. Isfahan 81746-73441 Iran

The aim of this study is to use a new configuration of porous media in a heat exchanger in continuous hydrothermal flow synthesis(CHFS)system to enhance the heat transfer and minimize the required length of the heat *** this purpose,numerous numerical simulations are performed to investigate performance of the system with porous ***,the numerical simulation for the heat exchanger in CHFS system is validated by experimental ***,porous media is added to the system and six different thicknesses for the porous media are examined to obtain the optimum thickness,based on the minimum required length of the heat ***,by changing the flow rate and inlet temperature of the product as well as the cooling water flow rate,the minimum required length of the heat exchanger with porous media for various inlet conditions is *** investigations indicate that using porous media with the proper thickness in the heat exchanger increases the cooling rate of the product by almost 40% and reduces the required length of the heat exchanger by approximately 35%.The results also illustrate that the most proper thickness of the porous media is approximately equal to 90% of the product tube's *** of this study lead to design a porous heat exchanger in CHFS system for various inlet conditions.

关键词：多孔介质结构合成系统换热器传热设计强化传热数值研究连续流动水热

Simulation of particles settling in power-law fluids by combined lattice Boltzmann-smoothed profile methods

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International Journal of Sediment Research 2021年第5期36卷 637-655页

作者： Hamideh Rouhani Tazangi Ataallah Soltani Goharrizi ebrahim Jahanshahi Javaran Department of Chemical Engineering Shahid Bahonar University of Kerman Department of Mechanical Engineering Shahid Bahonar University of Kerman

In the current study, the settling, interaction, drafting, kissing, and tumbling of two identical and nonidentical circular particles were simulated in a two-dimensional box in shear-thinning, Newtonian,and shear-thickening fluids by using the combined lattice Boltzmann-smoothed profile ***, the drag coefficient of one particle settling for different power-law indexes and Archimedes numbers was calculated. Also, the effect of the diameter ratio of the two particle pairs was considered during settling. The developed method was validated by simulating the settling of one particle and two identical particles in a Newtonian fluid. To consider two non-identical particles, two cases were examined. In Case A, the larger particle was above the smaller one and in the Case B, the smaller particle was above the larger one. The results showed that the two non-identical particles were separated more easily than the identical ones. In the settling of two particles under the same Archimedes number, the drafting and kissing time considerably increased by changing the non-Newtonian fluid behavior from a shearthinning one to a shear-thickening one. Also, when the larger particle was above the smaller one, the time duration of the kissing stage increased with the decrease in the diameter ratio.

关键词： Lattice Boltzmann method Smoothed profile method DKT phenomenon Power-law fluids Particulate flow Drag coefficient

The Outcome of Posterior Spinal Fusion and Instrumentation of Adolescent Idiopathic Scoliosis without Wound Suction Drainage

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Open Journal of Orthopedics 2023年第1期13卷 23-30页

作者： ebrahim Ghayem Hassankhani Golnaz Ghayyem Hassankhani Solmaz Ghayyem Hassankhani Pharmsist Orthopedic Research Center Mashhad University of Medical Sciences Mashhad Iran Orthopedic Research Center Ghaem Hospital Mashhad University of Medical Sciences Mashhad Iran Umea University Umea Sweden

Background: In spine surgery postoperative closed suction drainage is used to decrease the potential risks of wound hematoma formation, and reduces the risk of infection, cord compression and neurologic deficit. However, the efficacy of drains used for this purpose in adolescent idiopathic scoliosis is controversial. The purpose of this study is to evaluate outcomes of patients after posterior spinal fusion with instrumentation for adolescent idiopathic scoliosis without wound suction drainage. Methods: A total of 66 Patients who underwent posterior spinal fusion and instrumentation for the correction of Adolescent idiopathic scoliosis without the use of drain from January 2012 to January 2021 were included. Wound dehiscence, wound hematoma, infection, preoperative and postoperative hemoglobin levels and need for transfusion were described as frequency and mean values. Results: The average age was 15.06 years. Hospital stay was 2.2 days. Patients were followed-up over 50.21 months. There was no deep infection, wound hematoma. The difference between just postoperative and three days after operation hemoglobin levels was not significant and no need for transfusion. Only 3 (4.5%) cases with superficial skin infection and 4 (6%) cases with skin and Wound dehiscence were treated with dressing and antibiotics with full recovery. Conclusion: Without using drain for patients with idiopathic scoliosis who underwent posterior spinal fusion and instrumentation, no increase in blood loss, transfusion requirements, wound infection, skin dehiscence, and wound hematoma was observed.

关键词： Posterior Spinal Fusion Adolescent Idiopathic Scoliosis Wound Suction Drainage

Coal rib response during bench mining: A case study

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International Journal of Mining Science and Technology 2018年第1期28卷 107-113页

作者： Morgan M.Sears John Rusnak Mark Van Dyke Gamal rashed Khaled Mohamed Michael Sloan Ground Control Branch NIOSH Pittsburgh Mining Research Division

In 2016, room-and-pillar mining provided nearly 40% of underground coal production in the United *** the past decade, rib falls have resulted in 12 fatalities, representing 28% of the ground fall fatalities in *** coal *** of these 12 fatalities(75%) have occurred in room-andpillar *** objective of this research is to study the geomechanics of bench room-and-pillar mining and the associated response of high pillar ribs at overburden depths greater than 300 *** paper provides a definition of the bench technique, the pillar response due to loading, observational data for a case history, a calibrated numerical model of the observed rib response, and application of this calibrated model to a second site.

关键词： Deep cover Bench mining Thick seam Retreat mining Rib response Rib support