检索结果-南通市图书馆

Drilling signals analysis for tricone bit condition monitoring

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2021年第2期31卷 187-195页

作者： hamed rafezi Ferri Hassani Department of Mining and Materials Engineering McGill UniversityMontreal H3A 0G4Canada

This paper presents a novel approach to investigate the relations between drilling signals and bit wear condition in real world full-scale mining *** research addresses the increasing demand for automation in mining to increase the efficiency,safety,and ability to work in harsh environments.A crucial issue in fully autonomous unmanned drilling is to have a system to detect the bit wear condition through the drilling signals analysis in real *** this work,based on extensive field studies,a novel qualitative method for tricone bit wear state classification is developed and *** relations between drilling vibration as well as electric motor current signals and bit wear are investigated and bit failure vibration frequencies,regardless of the geological conditions,are *** failure frequencies are experimentally investigated and analytically ***,the effect of bit design parameters on the failure frequencies is presented for the application of bit wear condition monitoring and bit failure prediction.

关键词： Drilling Tricone bit Vibration Wear Condition monitoring Failure prediction

Experimental investigation on the effects of microwave irradiation on kimberlite and granite rocks

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2021年第2期13卷 267-274页

作者： Samir M.Deyab hamed rafezi Ferri Hassani Mehrdad Kermani Agus P.Sasmito Department of Mining and Materials Engineering McGill UniversityMontrealCanada

This study is a part of an overall research project on the effects of microwave(MW)irradiation on rocks for assisted rock breaking systems as well as mineral processing at McGill *** the first time,this paper highlights a comprehensive investigation on the effects of microwave irradiation on Canadian *** contribution to the continuous rock excavation and rock weakening effect prior to implementation of mechanical techniques was *** different kimberlite rocks,*** kimberlite(VK)and hypabyssal kimberlite(HK),and granite samples were *** important physical properties of the rock samples were measured including rock quality designation(RQD),specific gravity,porosity,and specific heat *** samples were treated for various exposure times using a multi-mode MWunit at different power levels ranging from 2 kW to 15 *** effect of MW irradiation on rock samples was *** results indicate that the mechanical properties including unconfined compressive strength(UCS)and Brazilian tensile strength(BTS)were significantly dropped as a result of ***,the effect on rock abrasivity using the Cerchar abrasivity index(CAI)has also been discussed.

关键词： Microwave irradiation Kimberlite Rock excavation Rock strength Abrasivity

Comparative CFD-DEM study of flow regimes in spout-fluid beds

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第2期85卷 323-334页

作者： hamed Hoorijani Behrad Esgandari Reza Zarghami Rahmat Sotudeh-Gharebagh Navid Mostoufi Multiphase Systems Research Lab School of Chemical EngineeringCollege of EngineeringUniversity of TehranP.O.Box 11155-4563TehranIran Department of Particulate Flow Modelling Johannes Kepler UniversityAltenbergerstr.694040LinzAustria

Spout-fluid beds are unique systems that require thorough study prior to their industrial *** this study,the hydrodynamics of spout-fluid beds were investigated using 3D computational fluid dy-namics coupled with discrete element method(CFD-DEM).Three flow regimes,including jet-in-fluidized bed,spouting-with-aeration,and intermediate/spout-fluidization were studied,and the particle mixing was quantified in these regimes using the Lacey mixing *** results showed that both axial and lateral mixing rates are better in jet-in-fluidized bed and the spouting-with-aeration flow regimes,with the axial mixing being superior to the lateral in all flow *** the diffusivity coefficient revealed that mixing in the jet-in-fluidized bed flow regime is better due to the formation and eruption of bubbles in the ***,the granular temperature was analyzed in all flow regimes,and higher particle velocity fluctuations were observed in the spouting-with-aeration and the jet-in-fluidized bed flow regimes due to the higher spout gas velocity and formation of bubbles in the *** study provides valuable insights into the hydrodynamics of spout-fluid beds in different flow regimes,which can aid in the design and optimization of spout-fluid bed reactors for various industrial applications.

关键词： Flow regime Mixing Diffusivity CFD-DEM Hydrodynamics Spout-fluid bed

非等温时效对含银Al-Mg-Si合金多层摩擦表面显微组织和腐蚀行为的影响

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2024年第2期34卷 408-422页

作者： hamed JAMSHIDI AVAL Department of Materials Engineering Babol Noshirvani University of TechnologyBabol47148-71167Iran

研究非等温时效对添加不同银含量Al-Mg-Si合金多层摩擦表面显微组织和腐蚀行为的影响。通过在耗材棒横截面上钻孔的方式添加4%、8%和13%(质量分数)的银。采用光学显微镜和电子显微镜研究涂层的显微组织,采用显微硬度和拉伸实验研究涂层... 详细信息

研究非等温时效对添加不同银含量Al-Mg-Si合金多层摩擦表面显微组织和腐蚀行为的影响。通过在耗材棒横截面上钻孔的方式添加4%、8%和13%(质量分数)的银。采用光学显微镜和电子显微镜研究涂层的显微组织,采用显微硬度和拉伸实验研究涂层的力学性能,采用电化学测试研究样品的耐腐蚀性。结果表明,随着银添加量从4%(质量分数)增加到13%(质量分数),摩擦堆焊表面层的晶粒尺寸从(1.5±0.3)μm减小到(1.0±0.3)μm。铝基体中的溶质银能够加速Al-Mg-Si合金的析出动力学。经非等温时效处理后,含银涂层的屈服强度和抗拉强度分别比不含银涂层高50.6%和43.5%。经非等温时效处理后,材料的腐蚀电流密度降低,含银和不含银样品的耐腐蚀性均提高,含银涂层的耐蚀性比无银镀层提高了96.5%。

关键词：非等温时效显微组织腐蚀行为 Al-Mg-Si合金银添加剂多层摩擦堆焊

Integrated hazard assessment of rockfall incidents in the Cap Aokas Cliff Region

在线全文

学校读者我要写书评

暂无评论

Journal of Mountain Science 2024年第6期21卷 1916-1929页

作者： Zohra LADJEL Farid ZAHRI Riheb HADJI Younes hamed Karim ZIGHMI Kaddour BENMARCE Department of Earth Sciences Institute of Architecture and Earth SciencesFerhat Abbas UniversitySetif 19137Algeria Unit of Emerging Materials Research Ferhat Abbes UniversitySétif 19137Algeria Laboratory of Applied Research in Engineering Geology GeotechnicsWater Sciencesand EnvironmentFerhat Abbas UniversitySetif 19137Algeria International Association of Water Resources in the Southern Mediterranean Basin Gafsa 2112Tunisia Department of Earth Sciences Faculty of SciencesUniversity of GafsaGafsa 2112Tunisia

Rock fall accidents in mountainous cliff areas have significant consequences for human life and *** study aimed to evaluate the rockfall hazard in the Cap Aokas cliff region located along the northeast coast of Algeria by identifying the key factors contributing to rockfall *** employed a combination of kinematic analysis,Matterocking method,and 3D trajectory simulations to determine zones that are susceptible to rockfall *** using a probabilistic and structural approach in conjunction with photogrammetry,we identified the controlling *** kinematic analysis revealed the presence of five discontinuity families,which indicated both plane and wedge failure *** 3D trajectory simulations demonstrated that the falling blocks followed the stream *** then validated the susceptibility maps generated from the analysis using aerial photos and historical rockfall *** findings of this study enhance our understanding of rockfall phenomena and provide valuable insights for the development of effective strategies to mitigate rockfall hazards.

关键词： Trajectory simulations Probabilistic analysis Structural approach Rockfall hazard Cap Aokas cliff

Combinational therapy with Myc decoy oligodeoxynucleotides encapsulated in nanocarrier and X-irradiation on breast cancer cells

在线全文

学校读者我要写书评

暂无评论

Oncology Research 2024年第2期32卷 309-323页

作者： BEHROOZ JOHARI MILAD PARVINZAD LEILAN MAHMOUD GHARBAVI YOUSEF MORTAZAVI ALI SHARAFI hamed REZAEEJAM Department of Medical Biotechnology School of MedicineZanjan University of Medical SciencesZanjanIran Zanjan Pharmaceutical Biotechnology Research Center Zanjan University of Medical SciencesZanjanIran Nanotechnology Research Center Ahvaz Jundishapur University of Medical SciencesAhvazIran Department of Radiology Technology School of Allied Medical SciencesZanjan University of Medical SciencesZanjanIran

The Myc gene is the essential oncogene in triple-negative breast cancer(TNBC).This study investigates the synergistic effects of combining Myc decoy oligodeoxynucleotides-encapsulated niosomes-selenium hybrid nanocarriers with X-irradiation exposure on the MDA-MB-468 cell *** and scramble ODNs for Myc transcription factor were designed and synthesized based on promoter sequences of the Bcl2 *** nanocarriers were synthesized by loading Myc ODNs and selenium into chitosan(Chi-Se-DEC),which was then encapsulated in niosome-nanocarriers(NISM@Chi-Se-DEC).FT-IR,DLS,FESEM,and hemolysis tests were applied to confirm its characterization and physicochemical ***,cellular uptake,cellular toxicity,apoptosis,cell cycle,and scratch repair assays were performed to evaluate its anticancer effects on cancer *** anticancer assessments were repeated under X-ray irradiation conditions(fractionated 2Gy).Physicochemical characteristics of niosomes containing SeNPs and ODNs showed that it is synthesized *** revealed that the anticancer effect of NISM@Chi-Se-DEC can be significantly improved in combination with X-ray irradiation *** can be concluded that NISM@Chi-Se-DEC nanocarriers have the potential as a therapeutic agent for cancer treatment,particularly in combination with radiation therapy and in-vivo experiments are necessary to confirm the efficacy of this nano-drug.

关键词： Combinational therapy Antisense therapy Myc signaling pathway Niosomes Radiation therapy SeNPs

Interplay between temperature-dependent strengthening mechanisms and mechanical stability in high-performance austenitic stainless steels

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2182-2188页

作者： Mohammad Javad Sohrabi hamed Mirzadeh Saeed Sadeghpour Milad Zolfipour Aghdam Abdol Reza Geranmayeh and Reza Mahmudi School of Metallurgy and Materials Engineering College of EngineeringUniversity of Tehran14395-515 TehranIran Centre for Advanced Steels Research Materials and Mechanical EngineeringUniversity of Oulu90014 OuluFinland Department of Mechanical Engineering College of EngineeringUniversity of Tehran14395-515 TehranIran

The effects of deformation temperature on the transformation-induced plasticity(TRIP)-aided 304L,twinning-induced plasti-city(TWIP)-assisted 316L,and highly alloyed stable 904L austenitic stainless steels were compared for the first time to tune the mechan-ical properties,strengthening mechanisms,and strength-ductility *** this purpose,the scanning electron microscopy(SEM),electron backscattered diffraction(EBSD),X-ray diffraction(XRD),tensile testing,work-hardening analysis,and thermodynamics calcu-lations were *** induced plasticity effects led to a high temperature-dependency of work-hardening behavior in the 304L and 316L stainless *** the deformation temperature increased,the metastable 304L stainless steel showed the sequence of TRIP,TWIP,and weakening of the induced plasticity mechanism;while the disappearance of the TWIP effect in the 316L stainless steel was also ***,the solid-solution strengthening in the 904L superaustenitic stainless steel maintained the tensile properties over a wide temper-ature range,surpassing the performance of 304L and 316L stainless *** this regard,the dependency of the total elongation on the de-formation temperature was less pronounced for the 904L alloy due to the absence of additional plasticity *** results re-vealed the importance of solid-solution strengthening and the associated high friction stress for superior mechanical behavior over a wide temperature range.

关键词： austenitic stainless steels mechanical behavior stacking fault energy metastability mechanical twinning

Groundwater vulnerability assessment using a GIS-based DRASTIC method in the Erbil Dumpsite area (Kani Qirzhala), Central Erbil Basin, North Iraq

在线全文

学校读者我要写书评

暂无评论

Journal of Groundwater Science and Engineering 2024年第1期12卷 16-33页

作者： Masoud H hamed Rebwar N Dara Marios C Kirlas Department of Earth Sciences and Petroleum College of ScienceSalahaddin University-ErbilErbilIraq Department of Petroleum Engineering College of EngineeringKnowledge UniversityErbilIraq Department of Agriculture Faculty of AgricultureForestry and Natural EnvironmentAristotle University of Thessaloniki

Groundwater vulnerability assessment is a crucial step in the efficient management of groundwater resources,especially in areas with intensive anthropogenic activities and groundwater *** the present study,the DRASTIC method was applied using Geographic Information System(GIS)to delineate groundwater vulnerability zones in the Erbil Dumpsite area,Central Erbil Basin,North *** showed that the area was classified into four vulnerability classes:Very low(16.97%),low(27.67%),moderate(36.55%)and high(18.81%).The southern,south-eastern and northern parts of the study area exhibited the highest vulnerability potential,while the central-northern,northern and north-western regions displayed the lowest vulnerability ***,results of the single-parameter sensitivity analysis indicated that amongst the seven DRASTIC parameters,the unsaturated zone and the aquifer media were the most influencing *** conclustion,the correlation of 25 nitrate concentration values with the final vulnerability map,assessed using the Pearson correlation coefficient,yielded a satisfactory result of R=0.72.

关键词： DRASTIC Erbil Iraq Groundwater vulnerability assessment Nitrate Pollution Sensitivity analysis

考虑气动载荷的超级高铁系统混合悬挂吊舱稳定性分析

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2024年第4期40卷 199-211页

作者： hamed Petoft Abbas Rahi Vahid Fakhari Faculty of Mechanical and Energy Engineering Shahid Beheshti UniversityTehran***Iran

超级高铁运输技术(HTT)是一种新型运输方式.它的工作原理是将一种称为吊舱的超高速车辆移动到低气压管中.本文研究了考虑空气动力载荷的新型混合悬浮吊舱的稳定性分析.拟议的吊舱包含两个悬浮装置:磁悬浮(EMS)和气垫.在这方面,气垫有助... 详细信息

超级高铁运输技术(HTT)是一种新型运输方式.它的工作原理是将一种称为吊舱的超高速车辆移动到低气压管中.本文研究了考虑空气动力载荷的新型混合悬浮吊舱的稳定性分析.拟议的吊舱包含两个悬浮装置:磁悬浮(EMS)和气垫.在这方面,气垫有助于系统克服整体重量.EMS悬架有两个比例微分(PD)控制器,可在存在空气动力载荷的情况下稳定吊舱的运动:一个控制垂直位移,另一个控制横向运动.本文建立了吊舱的五自由度动力学模型,包括吊舱的垂直和横向位移以及吊舱的俯仰、滚转和偏航力矩.介绍了气垫、磁悬浮和空气动力载荷的动态模型.求解相关动力学方程后,研究了控制器参数和气动升力和阻力载荷对吊舱稳定性的影响.此外,还分析了控制器系数和其他一些吊舱设计参数(包括气垫刚度、总质量和管内气压)对临界速度的影响.

关键词：横向运动空气动力载荷横向位移磁悬浮吊舱偏航力矩混合悬浮整体重量