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Experimental investigation of different brines imbibition influences on co-and counter-current oil flows in carbonate reservoirs

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Chinese Journal of Chemical Engineering 2021年第5期34卷 17-29页

作者： Pouyan Ahmadi mohammad Reza Aghajanzadeh Masoud Riazi mohammad Reza Malayeri mohammad Sharifi Enhanced Oil Recovery(EOR)Research Centre IOR/EOR Research InstituteShiraz UniversityShirazIran Helmholtz Centre for Environmental Research-UFZ LeipzigGermany Department of Petroleum Engineering Amirkabir University of TechnologyTehranIran Institut für Verfahrenstechnik und Umwelttechnik Technische Universität DresdenGermany

Imbibition of water,as wetting phase in oil-wet fractured carbonate reservoirs,plays a key role in fluid flow between matrix and fracture *** type of injected seawater and its chemistry would profoundly influence the imbibition *** this study,the impact of smart water(a brine that its ions have been adjusted to facilitate oil recovery)and low salinity water on co-and counter-current imbibition processes for oil-wet carbonate cores has been experimentally *** results show an increase of about 10% in oil recovery for co-and counter-currents for smart seawater imbibition compared to that of low salinity *** addition,as a result of the influence of co-and counter-current on each other,by co-current removal from one core face,the countercurrent in the other face would be intensified by as much as about 75%.A close examination of different lengths(5,7 and 9 cm)of carbonate cores with the same permeability revealed that by decreasing porous medium length,the amount of counter-current producing oil would be decreased so that in the 5 cm core,counter current oil production will not *** similar core lengths by increasing permeability,the share of counter current flow would be decreased approximately 18% since the capillary pressure could not overcome non-wetting phase viscous *** the role of matrix length along with a modified brine(which is designed according to the matrix mixture)strengthen the relevant mechanisms to have more oil production so that the higher thickness of matrix causes the higher amount of co-current oil producing and consequently more total recovery.

关键词： Smart water Co-current Counter current Wettability alteration Oil recovery

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Mineralogical and sink-float studies of Jajarm low-grade bauxite

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International Journal of Minerals,Metallurgy and Materials 2010年第3期17卷 251-256页

作者： mohammad Zarbayani Esmaeil Jorjani Mirsaleh Mirmohammadi mohammad Taghi Shadloo mohammad Noaparast Science and Research Branch Islamic Azad University School of Mining Engineering University of Tehran Jajarm Alumina Company

Jajarm＇s bauxite deposits are mainly diasporic, and they have a low mass ratio of Al2O3/SiO2. It is necessary to increase the run-of-mine mass ratio before feeding the material to the Bayer process. Chemical analysis indicated that the low-grade bauxite sample from Jajarm contained 43.9wt% Al2O3 and 13.35wt% SiO2, resulting in a mass ratio of 3.29. According to mineralogical studies, the presence of aluminosilicate minerals such as kaolinite, illite, and quartz was the main reason for the decrease of the mass ratio. Microscopic observations revealed that, with the size reduction from -1000＋710 to -38 μm, the liberation degree of diaspore increased from 10% to 60%, and that of aluminosilicates increased from 20% to 85%. Heavy liquids with the densities of 2.8, 3.0, 3.2, and 3.4 g/cm3 were used to evaluate the heavy media separation in three sizes, i.e., -3350＋710, -710＋212, and -212＋125 μm. Laboratory studies confirm that the density of 3.2 g/cm3 can produce the concentrates （in sunk fractions） with recoveries of 89.09%, 91.24%, and 84.68% with the Al2O3/SiO2 mass ratios of 5.03, 5.16, and 5.15 for the -3350＋710, -710＋212, and -212＋ 125 μ m sizes, respectively.

关键词： bauxite diaspore aluminosilicate mass ratio heavy media

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Carbon mineralization in subtropical alluvial arable soils amended with sugarcane bagasse and rice husk biochars

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Pedosphere 2022年第3期32卷 475-486页

作者： mohammad Arifur RAHMAN mohammad Abdul KADER mohammad JAHIRUDDIN mohammad Rafiqul ISLAM Zakaria mohammad SOLAIMAN Regional Agricultural Research Station(RARS) Bangladesh Agricultural Research Institute(BARI)Jamalpur 2000(Bangladesh) School of Agriculture GeographyEnvironmentOcean and Natural SciencesUniversity of South PacificApia 1343(Samoa) Department of Soil Science Bangladesh Agricultural University(BAU)Mymensingh 2202(Bangladesh) UWA School of Agriculture&Environment and the UWA Institute of Agriculture PerthWA 6009(Australia) School of Veterinary and Life Science Murdoch UniversityMurdochWA 6150(Australia)

Subtropical recent alluvial soils are low in organic carbon(C).Thus,increasing organic C is a major challenge to sustain soil *** amendment could be an option as biochar is a C-rich pyrolyzed material,which is slowly decomposed in *** investigated C mineralization(CO_(2)-C evolution)in two types of soils(recent and old alluvial soils)amended with two feedstocks(sugarcane bagasse and rice husk)(1%,weight/weight),as well as their biochars and aged biochars under a controlled environment(25±2℃)over 85 *** the recent alluvial soil(charland soil),the highest absolute cumulative CO_(2)-C evolution was observed in the sugarcane bagasse treatment(1140 mg CO_(2)-C kg^(-1)soil)followed by the rice husk treatment(1090 mg CO_(2)-C kg^(-1)soil);the lowest amount(150 mg CO_(2)-C kg^(-1)soil)was observed in the aged rice husk biochar ***,for the old alluvial soil(farmland soil),the highest absolute cumulative CO_(2)-C evolution(1290 mg CO_(2)-C kg^(-1)soil)was observed in the sugarcane bagasse treatment and then in the rice husk treatment(1270 mg CO_(2)-C kg^(-1)soil);the lowest amount(200 mg CO_(2)-C kg^(-1)soil)was in the aged rice husk biochar *** sugarcane bagasse and rice husk biochar treatments reduced absolute cumulative CO_(2)-C evolution by 10%and 36%,respectively,compared with unamended recent alluvial soil,and by 10%and 18%,respectively,compared with unamended old alluvial *** absolute and normalized C mineralization were similar between the sugarcane bagasse and rice husk treatments,between the biochar treatments,and between the aged biochar *** both soils,the feedstock treatments resulted in the highest cumulative CO_(2)-C evolution,followed by the biochar treatments and then the aged biochar *** absolute and normalized CO_(2)-C evolution and the mineralization rate constant of the stable C pool(K_(s))were lower in the recent alluvial soil compared with those in the old alluvial *** biochar

关键词： aged biochar biochar amendment charland CO_(2)emission CO_(2)-C evolution recent alluvial soil soil organic carboon soil organic matter

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Predicting seismic permanent displacement of soil walls under surcharge based on limit analysis approach

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Earthquake Engineering and Engineering Vibration 2018年第4期17卷 747-759页

作者： mohammad Mahdi Aminpour mohammad Maleki Ali Ghanbari Faculty of Engineering Bu-Ali Sina University Faculty of Engineering Kharazmi University

Seismic permanent displacement of the soil walls plays an important role in design of these structures. Due to the increase in growth of urban areas and the limitations in use of flat grounds, many structures are built near slopes and retaining walls. During earthquakes, these structures can apply an additional surcharge on the wall. The intensity and location of the surcharge is of considerable importance on the seismic displacements of the soil wall. In this study, by using the limit analysis and upper bound theorem, seismic permanent displacement of the soil wall under surcharge has been analyzed. Thus, a formulation is presented for calculating the yield acceleration and seismic displacement for different surcharge conditions. The effect of seismic acceleration, surcharge intensity, its location and soil properties is investigated. A parameter called the ＂displacement coefficient＂ is proposed, and is a potential modification for Newmark’s sliding-block method.

关键词： limit analysis surcharge soil wall seismic displacement yield acceleration

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A Nonlinear Coordinated Approach to Enhance the Transient Stability of Wind Energy-Based Power Systems

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IEEE/CAA Journal of Automatica Sinica 2020年第4期7卷 1087-1097页

作者： mohammad Javad Morshed the Department of Electrical and Computer Engineering University of Louisiana at LafayetteLafayetteLA 70504 USA

This paper proposes a novel framework that enables the simultaneous coordination of the controllers of doubly fed induction generators(DFIGs) and synchronous generators(SGs).The proposed coordination approach is based on the zero dynamics method aims at enhancing the transient stability of multi-machine power systems under a wide range of operating conditions. The proposed approach was implemented to the IEEE39-bus power systems. Transient stability margin measured in terms of critical clearing time along with eigenvalue analysis and time domain simulations were considered in the performance assessment. The obtained results were also compared to those achieved using a conventional power system stabilizer/power oscillation(PSS/POD) technique and the interconnection and damping assignment passivity-based controller(IDA-PBC). The performance analysis confirmed the ability of the proposed approach to enhance damping and improve system’s transient stability margin under a wide range of operating conditions.

关键词： Doubly fed induction generator(DFIG) excitation controller multi-machine power system synchronous generator(SG) transient stability zero dynamics

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A novel technology for control of variable speed pumped storage power plant

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Journal of Central South University 2016年第8期23卷 2008-2023页

作者： Seyed mohammad Hassan Hosseini mohammad Reza Semsar Department of Electrical Engineering Islamic Azad University

Variable speed pumped storage machines are used extensively in wind power plant and pumped storage power plant. This paper presents direct torque and flux control(DTFC) of a variable speed pumped storage power plant(VSPSP). By this method both torque and flux have been applied to control the VSPSP. The comparison between VSPSP's control strategies is studied. At the first, a wind turbine with the capacity 2.2 k W and DTFC control strategies simulated then a 250 MW VSPSP is simulated with all of its parts(including electrical, mechanical, hydraulic and its control system) by MATLAB software. In all of simulations, both converters including two-level voltage source converter(2LVSC) and three-level voltage source converter(3LVSC) are applied. The results of applying 2LVSC and 3LVSC are the rapid dynamic responses with better efficiency, reducing the total harmonic distortion(THD) and ripple of rotor torque and flux.

关键词： direct torque and flux control(DTFC) two-level & three-level voltage source converter(2LVSC&3LVSC) variable speed pumped storage power plant(VSPSP)

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A new robust fuzzy method for unmanned flying vehicle control

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Journal of Central South University 2015年第6期22卷 2166-2182页

作者： Mojtaba Mirzaei mohammad Eghtesad mohammad Mahdi Alishahi Department of Mechanical Engineering Shiraz University

A new general robust fuzzy approach was presented to control the position and the attitude of unmanned flying vehicles(UFVs). Control of these vehicles was challenging due to their nonlinear underactuated behaviors. The proposed control system combined great advantages of generalized indirect adaptive sliding mode control(IASMC) and fuzzy control for the UFVs. An on-line adaptive tuning algorithm based on Lyapunov function and Barbalat lemma was designed, thus the stability of the system can be guaranteed. The chattering phenomenon in the sliding mode control was reduced and the steady error was also alleviated. The numerical results, for an underactuated quadcopter and a high speed underwater vehicle as case studies, indicate that the presented adaptive design of fuzzy sliding mode controller performs robustly in the presence of sensor noise and external disturbances. In addition, online unknown parameter estimation of the UFVs, such as ground effect and planing force especially in the cases with the Gaussian sensor noise with zero mean and standard deviation of 0.5 m and 0.1 rad and external disturbances with amplitude of 0.1 m/s2 and frequency of 0.2 Hz, is one of the advantages of this method. These estimated parameters are then used in the controller to improve the trajectory tracking performance.

关键词： adaptive fuzzy sliding-mode control unmanned flying vehicle control underactuated system Lyapunov stability high speed underwater vehicle

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Risk-based probabilistic thermal-stress analysis of concrete arch dams

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Frontiers of Structural and Civil Engineering 2019年第5期13卷 1007-1019页

作者： Narjes SOLTANI mohammad ALEMBAGHERI mohammad Houshmand KHANEGHAHI Department of Civil and Environmental Engineering Tarbiat Modares UniversityTehran ***Iran Department of Civil Engineering Shahid Beheshti UniversityTehran ***Iran

The probabilistic risk of arch dam failure under thermal loading is studied. The incorporated uncertainties, which are defined as random variables, are associated with the most affecting structural (material) properties o f concrete and thermal loading conditions. Karaj arch dam is selected as case study. The dam is numerically modeled along with its foundation in three-dimensional space;the temperature and thermal stress distribution is investigated during the operating phase. The deterministic thermal finite element analysis o f the dam is combined with the structural reliability methods in order to obtain thermal response predictions, and estimate the probability o f failure in the risk analysis context. The tensile overstressing failure mode is considered for the reliability analysis. The thermal loading includes ambient air and reservoir temperature variations. The effect o f solar radiation is considered by an increase in the ambient temperatures. Three reliability methods are employed: the first-order second-moment method, the first-order reliability method, and the Monte-Carlo simulation with Latin Hypercube sampling. The estimated failure probabilities are discussed and the sensitivity o f random variables is investigated. Although most of the studies in this line o f research are used only for academic purposes, the results of this investigation can be used for both academic and engineering purposes.

关键词： arch dams probabilistic analysis thermal stress sensitivity reliability

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Effects of floods on macroinvertebrate communities in the Zarin Gol River of northern Iran: implications for water quality monitoring and biological assessment

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Ecological Processes 2021年第1期10卷 608-618页

作者： mohammad Gholizadeh Department of Fisheries Faculty of Agriculture and Natural ResourcesGonbad Kavous UniversityBasirat BlvdShahid Fallshi StrGonbad KavousGolestan Province P.O.163Iran

Background:The timing,magnitude,and duration of extreme hydrological disasters have the potential to threaten the species diversity and river *** August 8,2014,and August 19,2017,disastrous floods struck mountainous regions of Iran’s Zarin Gol River *** communities were studied at seven upstreams prior to the floods in June 2014 and 2017 and after the floods in September 2014 and 2017 and 9 months after the second flood in June *** effects of floods on macroinvertebrate communities,recovery rate of macroinvertebrate community resilience and influencing factors were ***:Despite the fact that extreme floods were the only reason of the disruption,the effects of biological water quality assessment metrics after the disaster were comparable to those of heavily polluted *** indicators revealed that the communities were unaffected prior to the floods,and the water quality remained within acceptable *** the disasters,the density of macroinvertebrates declined,and biological indicators demonstrated the severe depletion of water *** indicators(species richness,percent model affinity(PMA),and Ephemeroptera,Plecoptera,and Trichoptera(EPT)richness)rebounded after 9 months(June 2018),demonstrating that Zarin Gol River’s macroinvertebrate communities could recover even after the severe impact of the *** a result,macroinvertebrate samples taken from flood-affected areas revealed that extreme flooding,rather than a decrease in water quality,causes a loss of diversity and ***:Because of shifts in hydrological regimes in streams around the world,understanding the short-term impacts of strong flooding and the comparatively quick recovery of macroinvertebrate ecosystems has important consequences for bio-assessment programs after severe floods.

关键词： Macroinvertebrate Climate change Bio-assessment Hydrology

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Effect of graphene oxide and reduced graphene oxide nanosheets on the microstructure and mechanical properties of mild steel jointing by flux-cored arc welding

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International Journal of Minerals,Metallurgy and Materials 2020年第4期27卷 505-514页

作者： mohammad Khosravi mohammad Mansouri Ali Gholami Yadollah Yaghoubinezhad Department of Mechanical Engineering Birjand University of Technology BirjandP.O.Box 97175-569235Iran Department of Materials Engineering Birjand University of Technology BirjandP.O.Box 97175-569315Iran

The effect of graphene oxide(GO)and reduced graphene oxide(RGO)nanosheets on the microstructure and mechanical properties of welded joints of mild steel was evaluated by flux-cored arc *** was synthesized by the Hummer’s method and was reduced under hydrothermal conditions at a pressure of 1.1 MPa at 180°C for 12 h.1,3,and 10 mg/mL paste fillers were used in GO and RGO,and applied to the weld *** results clearly showed that by increasing the concentration of RGO up to 10 mg/mL,the tensile strength and hardness of the weld metal were improved by approximately 20.5%and 38.4%,respectively,because the coarse grains were changed into fine *** domain of the nanosheets cluster was 19.85×10^?9 ***,the RGO nanosheets contributed to modifying the mechanical properties of the welded steel,likely due to dislocation pinning.

关键词： graphene oxide reduced graphene oxide flux-cored arc welding steel mechanical properties

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