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Mechanical and microstructural variations in ECAP of Ti-6Al-4V alloy with equiaxed microstructure

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Rare Metals 2022年第8期41卷 2732-2738页

作者： hamid Arabi mostafa Ketabchi S.h.N.Alhosseini Mining and Metallurgical Engineering Department Amirkabir University of TechnologyTehran***Iran University Complex of Material and Manufacturing Malek Ashtar University of TechnologyTehran***Iran

The aim of this study is to investigate mechanical and microstructural variations of Ti-6 Al-4 V acquired through various equal channel angular pressing(ECAP)*** ECAP of Ti-6 Al-4 V alloy with the first equiaxed micros tructure was carried out by an isothermal warm and isothermal die *** A pressing carried out on cylindrical samples at 650℃.Mechanical and microstructural investigations were performed concerning Ti-6 Al-4 V in the first state after 2,4,and 8 *** microscopy(OM)investigation shows that alpha grain size increases and beta grain size decreases with the pass numbers *** phase content initially decreases in the first two ECAP *** results show that more equiaxed alpha grains are achieved after four ECAP *** of X-ray diffraction(XRD)analysis show that crystallite size decreases with the number of passes *** two ECAP passes,a vivid increase in mechanical strength is observed;however,the increment dramatically slows down by the increasing number of passes.

关键词： Ti-6Al-4V alloy Equal channel angular pressing Equiaxed microstructure Mechanical properties

Catalytic behaviors of Co-Mn/TiO_2 catalysts for Fischer-Tropsch synthesis

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燃料化学学报 2012年第12期40卷 1435-1443页

作者： mostafa Feyzi Faculty of Chemistry Razi UniversityKermanshahIran

The 15%(Co-Mn)/TiO2,(Co/Mn=1/6) catalyst was prepared using fusion procedure and studied for the conversion of synthesis gas to C2 ～ 4 *** effects of calcination conditions and operation conditions such as the h 2 / CO molar feed ratio at different temperatures,gas hourly space velocity(GhSV) and total reaction pressure on the catalytic performance of catalyst were *** stability of the catalyst during 150 h at optimal operation conditions(t = 250℃ h2 /CO= 2/1,GhSV=1 500 h-1 and p =0.3 MPa) has been *** is found that this catalyst is high stable for production C2 ～ 4 *** of both precursors and calcined catalysts by powder X-ray diffraction,scanning electron microscopy(SEM),Brunauer-Emmett-Teller(BET) specific surface area measurement and thermal analysis methods such as thermal gravimetric analysis(TGA) and differential scanning calorimetry(DSC) show that the different preparation method influences the catalyst precursor structure and morphology.

关键词：气化理论燃料化学研究发展

Geology and geochemistry of the granitic rocks and associated dykes,East Gabal Nuqra,South Eastern Desert,Egypt

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Chinese Journal Of Geochemistry 2012年第4期31卷 376-389页

作者： Ibrahim h.Ibrahim mostafa E.Darwish Nuclear Material Authority 530 P.O.El MaadiCairoEgypt

A crescent-shape granitic stock and associated dykes is located to the East Gabal Nuqra at the extreme western part of Wadi Natash,South Eastern Desert,*** examined granites are classified as alkali-feldspar granites and mainly consist of quartz,potash feldspars,plagioclases,and ***,zircon,apatite and allanite are accessories representing the source of Y,U,Th and REEs in these *** granites are characterized by high K2O,Na2O and Zn contents and Rb/Sr ***,they are highly enriched in high field strength elements(hFSE),especially Zr(1529×10-6),Nb(100×10-6),hf(91×10-6) and Y(624×10-6) and light rare-earth elements(LREE,141×10-6) concentrations and strongly depleted in Ca,Mg,Sr and Eu *** features suggest that they are similar to A-type granites(type-2).The rhyolite dykes and granites have similar geochemical characteristics whereas the chondrite-normalized REE patterns show a LREE enriched feature with strong negative Eu-anomaly,whereas the REE pattern of trachydacites show slightly fractionated pattern with no *** is suggested that the trachydacites were generated by small degree of partial-melting deep-seated basic *** liquid,when subjected to fractional crystallization involving separation of plagioclases as residue,generated the alkali-feldspar *** further fractional crystallization gave rise to the alkali *** igneous rock suite originated from metaluminous to alkaline trachytic magma,and was developed in a within-plate tectonic *** extension caused by NW-SE right-lateral shear in area led to the emplacement of the alkali-feldspar *** later extrusion of the alkali rhyolite and trachydacite dykes was due to cauldron subsidence.

关键词：碱长花岗岩地球化学特征堤坝沙漠埃及轻稀土元素碱性流纹岩元素富集特征

Polyphenolic rich fraction of Physalis peruviana calyces and its nano emulsion induce apoptosis by caspase 3 up-regulation and G2/M arrest in hepatocellular carcinoma

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Food Bioscience 2022年第6期50卷 1314-1323页

作者： Doha h.Abou Baker Dina mostafa Mohammed Medicinal and Aromatic Plants Department National Research CentreDokkiCairo12622Egypt Nutrition and Food Science Department National Research CentreDokkiCairo12622Egypt

Phytocompounds found in fruit wastes serve as nature's precious gift to humans in cancer treatment. In this context, the present work aimed to use of Physalis peruviana calyces (PPC) and its nano-emulsion as a novel method in hepatocellular carcinoma treatment. PPC butanolic fraction (PPCBF) was prepared and tested for its total phenol, total flavonoids, and hPLC analysis for phenolics, as well as the in vitro anticancer activity for both normal and nano-emulsion was evaluated. Twenty-four male Sprague-Dawley rats were used;18 rats were administered intraperitoneally diethylnitrosamine (DEN) once (200 mg/kg body weight) in a saline solution. All nutritional parameters, biochemical parameters, and histopathological examinations were assessed. Results revealed that PPCBF and its nano-emulsion showed high anti -hepG2 activity and induced Pre-G1 apoptosis and cell cycle arrest (G2/M phase). Moreover, PPCBF and its nano-emulsion caused up-regulation of caspase-3 mRNA in hepG2, which could indicate that the intrinsic mitochondrial route triggered apoptosis. All the nutritional and biochemical changes were confirmed by histopathological examination. In conclusion, PPC and its nano-emulsion could be serving as a successful and effective drug from waste with a bright future in the treatment of hepatocellular carcinoma (hCC).

关键词： Physalis peruviana calyces Bioactive compounds hepatocellular carcinoma Nanotechnology Apoptosis Biochemical parameters

Synthesis,characterization and catalytic performance of nanosized iron-cobalt catalysts for light olefins production

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Journal of Natural Gas Chemistry 2011年第6期20卷 677-686页

作者： mostafa Feyzi Asadollah hassankhani Faculty of Chemistry Razi UniversityP.O.Box:+98-67149KermanshahIran Department of Materials Science International Center for ScienceHigh Technology & Environmental SciencesP.O.Box:+98-76315-117KermanIran

Nanosized Fe-Co catalysts were prepared by co-precipitation method and studied for the conversion of synthesis gas to light *** particular,the effects of a range of preparation variables such as Co/Fe molar ratios of the precipitation solution,ph value of precipitate,temperature of precipitation,promoters and loading of optimum promoter on the structure and catalytic performance are *** optimal nano catalyst for light olefins （C2-C4） production was obtained over the catalyst with Co/Fe molar ratio of 3/1 which promoted with 2 wt% *** results show that the best operational conditions were GhSV=2200 h^-1 （h2/CO=2/1） at 260℃ under atmospheric *** of catalysts were carried out using X-ray diffraction （XRD）,thermal gravimetric analysis （TGA）,differential scanning calorimetry （DSC）,scanning electron microscopy （SEM）,transmission electron microscopy （TEM） and N2 physisorption measurements such as Brunauer-Emmett-Teller （BET） and Barrett-Joyner-halenda （BJh） methods.

关键词： light olefins catalytic performance operational condition characterization

Environmental factors influencing the distribution of endangered endemic species hedysarum criniferum Boiss in arid and semi-arid rangelands,Iran

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Journal of Arid Land 2024年第12期16卷 1730-1743页

作者： Javid hAYATI hossein BAShARI Seyed h MATINKhAh hamid R KARIMZADEh mostafa TARKESh Department of Natural Resources Isfahan University of TechnologyIsfahan ***Iran

Understanding the factors influencing the distribution of plant species is crucial for enhancing the management of endangered ecosystems. This study investigated the response of hedysarum criniferum Boiss, an endemic and endangered species to 25 environmental variables within its habitats with an area of 2.95×10^(5) km^(2) in arid and semi-arid rangelands of Iran. The purpose of this research is to identify the key environmental factors affecting the distribution and habitat preferences of h. criniferum for further conservation and restoration of the species. To predict the occurrence of h. criniferum and explore its relationship with environmental factors, we employed the best subset regression analysis, the hierarchical classification, and the extended huisman-Olf-Fresco(ehOF) model. The results showed that four environmental variables, i.e., gravel content, ph, annual minimum temperature, and mean annual temperature showed significant correlations with the canopy cover of h. criniferum(Phe probability of h. criniferum occurrence increased with higher precipitation and elevation, while it decreased with higher mean annual temperature, annual minimum temperature, and gravel content. The species' response curves and their optimal values, as assessed by the ehOF model, indicated that the response to mean annual temperature, ranging from 12℃ to 16℃, was optimal at 13℃. The response to mean annual precipitation, within a range of 150–650 mm, was optimal at 650 mm. Elevation responses, spanning from 1546 to 2450 m, showed an optimum at 2450 m. Regarding soil characteristics, the response to gravel content, ranging from 13.0%–48.0%, demonstrated an optimal value at 20.0%. The ph levels, varying from 7.5 to 8.2, prompted a sine-shaped response with an optimal ph of 8.0. These findings provide valuable insights for predicting species occurrence and identifying suitable locations for restoration programs. Our study underscores the importance of considering multiple

关键词： habitat suitability species response curves best subset regression extended huisman-Olf-Fresco(ehOF)model hierarchical classification

A Comprehensive Review on Charging Topologies and Power Electronic Converter Solutions for Electric Vehicles

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 675-694页

作者： Abdelfatah Ali hossam h.h.Mousa mostafa F.Shaaban Maher A.Azzouz Ahmed S.A.Awad the Department of Electrical Engineering American University of Sharjah26666 SharjahUnited Arab Emirates the Department of Electrical Engineering South Valley University83523 QenaEgypt the Department of Electrical and Computer Engineering University of WindsorWindsorON N9B 3P4 Canada Electrical Engineering Department Qatar UniversityDoha 2713Qatar Department of Electrical and Computer Engineering Sultan Qaboos UniversityMuscat123Oman

Electric vehicles(EVs)are becoming more popular worldwide due to environmental concerns,fuel security,and price *** performance of EVs relies on the energy stored in their batteries,which can be charged using either AC(slow)or DC(fast)***,EVs can also be used as mobile power storage devices using vehicle-to-grid(V2G)*** electronic converters(PECs)have a constructive role in EV applications,both in charging EVs and in ***,this paper comprehensively investigates the state of the art of EV charging topologies and PEC solutions for EV *** examines PECs from the point of view of their classifications,configurations,control approaches,and future research prospects and their impacts on power *** can be classified into various topologies:DC-DC converters,AC-DC converters,DC-AC converters,and AC-AC *** address the limitations of traditional DC-DC converters such as switching losses,size,and high-electromagnetic interference(EMI),resonant converters and multiport converters are being used in high-voltage EV ***,power-train converters have been modified for high-efficiency and reliability in EV *** paper offers an overview of charging topologies,PECs,challenges with solutions,and future trends in the field of the EV charging station applications.

关键词： Charging station charging topology electric vehicle power electronic converter vehicle-to-grid

Multifunction Battery Energy Storage System for Distribution Networks

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Energy Engineering 2022年第2期119卷 569-589页

作者： Omar h.Abdalla Gamal Abdel-Salam Azza A.A.mostafa Department of Electrical Power&Machines Helwan UniversityCairoEgypt Technical Affairs Sectors South Cairo Electricity Distribution CompanyCairoEgypt Department of Energy Efficiency and Renewables Egyptian Electric Utility and Customer Protection Regulatory AgencyCairoEgypt

Battery Energy Storage System(BESS)is one of the potential solutions to increase energy system flexibility,as BESS is well suited to solve many challenges in transmission and distribution *** of distribution network’s challenges,which affect network performance,are:(i)Load disconnection or technical constraints violation,which may happen during reconfiguration after fault,(ii)Unpredictable power generation change due to Photovoltaic(PV)penetration,(iii)Undesirable PV reverse power,and(iv)Low Load Factor(LF)which may affect electricity *** this paper,the BESS is used to support distribution networks in reconfiguration after a fault,increasing Photovoltaic(PV)penetration,cutting peak load,and loading valley *** paper presents a methodology for BESS optimal locations and sizing considering technical constraints during reconfiguration after a fault and PV power generation *** determining themaximumpower generation change due to PV,actual power registration of connected PV plants in South Cairo Electricity Distribution Company(SCEDC)was considered for a *** addition,the paper provides a procedure for distribution network operator to employ the proposed BESS to perform multi functions such as:the ability to absorb PV power surplus,cut peak load and fill load valley for improving network’s *** methodology is applied to a modified IEEE 37-node and a real network part consisting of 158 nodes in SCEDC *** simulation studies are performed using the DIgSILENT PowerFactory software andDPL programming *** Mixed Integer Linear Programming optimization technique(MILP)in MATLAB is employed to choose the best locations and sizing of BESS.

关键词： Battery energy storage system photovoltaic penetration peak load reduction valley filling MILP optimization

Prediction of peak ground acceleration of Iran's tectonic regions using a hybrid soft computing technique

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Geoscience Frontiers 2016年第1期7卷 75-82页

作者： mostafa Gandomi Mohsen Soltanpour Mohammad R.Zolfaghari Amir h.Gandomi Department of Civil Engineering Khajeh Nasir Toosi University of Technology Department of Civil Engineering The University of Akron

A new model is derived to predict the peak ground acceleration（PGA） utilizing a hybrid method coupling artificial neural network（ANN） and simulated annealing（SA）, called SA-ANN. The proposed model relates PGA to earthquake source to site distance, earthquake magnitude, average shear-wave velocity,faulting mechanisms, and focal depth. A database of strong ground-motion recordings of 36 earthquakes,which happened in Iran’s tectonic regions, is used to establish the model. For more validity verification,the SA-ANN model is employed to predict the PGA of a part of the database beyond the training data domain. The proposed SA-ANN model is compared with the simple ANN in addition to 10 well-known models proposed in the literature. The proposed model performance is superior to the single ANN and other existing attenuation models. The SA-ANN model is highly correlated to the actual records（R=0.835 and r =0.0908） and it is subsequently converted into a tractable design equation.

关键词： Peak ground acceleration Artificial neural networks Simulated annealing Explicit formulation