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Effects of water content, water type and temperature on the rheological behaviour of slag-cement and fly ash-cement paste backfill

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International Journal of Mining Science and Technology 2020年第3期30卷 271-278页

作者： Yue Zhao abbas taheri Murat Karakus Zhongwei Chen An Deng School of Civil Environmental and Mining EngineeringThe University of AdelaideAdelaide 5005Australia School of Mechanical and Mining Engineering The University of QueenslandBrisbane 4072Australia

The pumping ability and placement performance of fresh cemented paste backfill(CPB) in underground mined cavities depend on its rheological properties. Hence, it is crucial to understand the rheology of fresh CPB slurry, which is related to CPB mixture design and the temperature underground. This paper presented an experimental study investigating the effects of binder type, content, water chemical properties and content, and temperature, on the rheological properties of CPB material prepared using the tailings of a copper mine in South Australia. Portland cement(PC), a newly released commercially manufactured cement called Minecem(MC) and fly ash(FA) were used as the binders added to the mine tailing materials. Various amounts of two different water types were added to the mixtures in the preparation of backfill material slurry. Six different temperatures ranging from 5 to 60 °C were to investigate the effect of temperature on CPB rheology. Overall, the increasing water content and decreasing temperature lead to lower yield stress. Based on the results obtained from the rheological properties of CPB slurry, it was found that at room temperature(25 °C), with regards to the unconfined compressive strength(UCS) performance, the replacement of 4% PC mixed CPB(28 days UCS 425 k Pa) to 3% MC mixed CPB(28 days UCS 519 k Pa), reduced the slurry yield stress from 210.7 to 178.5 Pa. The results also showed that the chemical composition of water affects the yield stress of CPB slurry and that MC mitigates the negative effect of mine-processed water(MW) and thus lead to improve the rheological properties of the slurry. However, the results suggested that the rheological properties of a mixture using MC is very sensitive to the water volume and temperature change. Therefore, using MC in backfill requires better quality control in slump mixing.

关键词： Cemented paste backfill Minecem Rheology Yield stress Fly ash Portland cement

Intermittent swelling and shrinkage of a highly expansive soil treated with polyacrylamide

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第1期14卷 252-261页

作者： Amin Soltani An Deng abbas taheri Brendan C.O’Kelly School of Engineering Information Technology and Physical SciencesFederation UniversityChurchillVIC3842Australia School of Civil Environmental and Mining EngineeringThe University of AdelaideAdelaideSA5005Australia Department of Civil Structural and Environmental EngineeringTrinity College DublinDublinD02 PN40Ireland

This laboratory study examines the potential use of an anionic polyacrylamide(PAM)-based material as an environmentally sustainable additive for the stabilization of an expansive soil from South *** experimental program consisted of consistency limits,sediment volume,compaction and oedometer cyclic swell-shrink tests,performed using distilled water and four different PAM-to-water solutions of P_(D)=0.1 g/L,0.2 g/L,0.4 g/L and 0.6 g/L as the mixing ***,the relative swelling and shrinkage strains were found to decrease with increasing number of applied swell-shrink cycles,with an‘elastic equilibrium’condition achieved on the conclusion of four *** propensity for swelling/shrinkage potential reduction(for any given cycle)was found to be in favor of increasing the PAM dosage up to P_(D)=0.2 g/L,beyond which the excess PAM molecules self-associate as aggregates,thereby functioning as a lubricant instead of a flocculant;this critical dosage was termed‘maximum flocculation dosage’(MFD).The MFD assertion was discussed and validated using the consistency limits and sediment volume properties,both exhibiting only marginal variations beyond the identified MFD of P_(D)=0.2 g/*** accumulated axial strain progressively transitioned from‘expansive’for the unamended soil to an ideal‘neutral’state at the MFD,while higher dosages demonstrated undesirable‘contractive’states.

关键词： Expansive soil Polyacrylamide(PAM) Consistency limits Sediment volume Swell-shrink cycles Swelling and shrinkage strains Accumulated axial strain

Evaluation of the propensity of strain burst in brittle granite based on post-peak energy analysis

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Underground Space 2021年第1期6卷 1-11页

作者： Selahattin Akdag Murat Karakus Giang D.Nguyen abbas taheri Thomas Bruning School of Civil Environmental and Mining EngineeringThe University of AdelaideAdelaideSAAustralia

The increasing demand for resources and depletion of near ground mineral resources caused deeper mining operations under highstress rock mass *** a result of this,strain burst,which is the sudden release of stored strain energy in the surrounding rock mass,has become more prevalent and created a considerable threat to workers and construction *** is,therefore,imperative to understand how strain burst mechanism and stored excess strain energy are affected due to the high confinement in deep underground *** this purpose,post-peak energy distributions for brittle rocks were investigated using a newly developed energy calculation method associated with acoustic emission(AE).A series of quasi-static uniaxial and triaxial compression tests controlled by the circumferential expansion were ***-back behaviour known as Class-II behaviour associated with energy evolution and the material response under self-sustaining failure were analysed on granites under a wide range of confining pressures(0–60 MPa).The experimental results underline that the energy evolution characteristics are strongly linked to *** elastic strain energy(dUE),energy consumed by dominating cohesion weakening(dUCW)and energy dissipated during mobilisation of frictional failure(dUFM)showed a rising trend as the confining pressure was *** intrinsic ejection velocity was proposed to express the propensity of strain burst that was purely determined by the excess strain energy released from Class II rock.

关键词： Strain burst Energy balance Class II failure mode Self-sustaining failure Triaxial compression test Circumferential strain control

Quantification of grain boundary effects on the geometrically necessary dislocation density evolution and strain hardening of polycrystalline Mg-4Al using in situ tensile testing in scanning electron microscope and HR-EBSD

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Journal of Magnesium and Alloys 2024年第5期12卷 1815-1829页

作者： Eunji Song Mohsen taheri Andani Amit Misra Department of Materials Science and Engineering University of MichiganAnn ArborMI 48109USA Department of Mechanical Engineering University of MichiganAnn ArborMI 48109USA Department of Mechanical Engineering Texas A&M UniversityCollege StationTX 77843USA

In situ tensile testing in a scanning electron microscope(SEM)in conjunction with high-resolution electron backscatter diffraction(HR-EBSD)under load was used to characterize the evolution of geometrically necessary dislocation(GND)densities at individual grain boundaries as a function of applied strain in a polycrystalline Mg-4Al *** increase in GND density was investigated at plastic strains of 0%,0.6%,2.2%,3.3% from the area including 76 grains and correlated with(i)geometric compatibility between slip systems across grain boundaries,and(ii)plastic *** develop expressions for the grain boundary GND density evolution as a function of plastic strain and plastic incompatibility,from which uniaxial tensile stress-strain response of polycrystalline Mg-4Al are computed and compared with experimental *** findings in this study contribute to understanding the mechanisms governing the strain hardening response of single-phase polycrystalline alloys and more reliable prediction of mechanical behaviors in diverse microstructures.

关键词： Mg-Al alloys Grain boundaries Geometrically necessary dislocations Strain gradient plasticity HR-EBSD

Exergy Analysis of Charge and Discharge Processes of Thermal Energy Storage System with Various Phase Change Materials:A Comprehensive Comparison

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Journal of Thermal Science 2024年第2期33卷 509-521页

作者： Mojtaba taheri Fathollah POURFAYAZ Roghayeh HABIBI Akbar MALEKI Department of Renewable Energies and Environment Faculty of New Sciences and TechnologiesUniversity of TehranTehran***Iran Faculty of Mechanical Engineering Shahrood University of TechnologyShahrood***Iran

Thermal energy storage(TES) is of great importance in solving the mismatch between energy production and *** this regard,choosing type of Phase Change Materials(PCMs) which are widely used to control heat in latent thermal energy storage systems,plays a vital role as a means of TES ***,this field suffers from lack of a comprehensive investigation on the impact of various PCMs in terms of *** address this issue,in this study,in addition to indicating the melting temperature and latent heat of various PCMs,the exergy destruction and exergy efficiency of each material are estimated and compared with each ***,in the present work the impact of PCMs mass and ambient temperature on the exergy efficiency is *** results proved that higher latent heat does not necessarily lead to higher exergy ***,to obtain a suitable exergy efficiency,the specific heat capacity and melting temperature of the PCMs must also be *** to the results,LiF-CaF_(2)(80.5%:19.5%,mass ratio) mixture led to better performance with satisfactory exergy efficiency(98.84%) and notably lower required mass compared to other ***,the highest and lowest exergy destruction are belonged to GR25 and LiF-CaF_(2)(80.5:19.5) mixture,respectively.

关键词： exergy analysis phase change materials thermal energy storage exergy efficiency

Remote condition monitoring of rail tracks using distributed acoustic sensing(DAS):A deep CNN-LSTM-SW based model

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Green Energy and Intelligent Transportation 2024年第5期3卷 70-85页

作者： Md Arifur Rahman Suhaima Jamal Hossein taheri The Laboratory for Advanced Non-Destructive Testing In-situ Monitoringand Evaluation(LANDTIE)Department of Manufacturing EngineeringGeorgia Southern UniversityStatesboro 30458GAUSA Information Technology Department Georgia Southern UniversityStatesboro 30458GAUSA

Railroad condition monitoring is paramount due to frequent passage through densely populated *** significance arises from the potential consequences of accidents such as train derailments,hazardous materials leaks,or collisions which may have far-reaching impacts on communities and the surrounding *** a solution to this issue,the use of distributed acoustic sensing(DAS)-fiber optic cables along railroads provides a feasible tool for monitoring the health of these extended ***,analyzing DAS data to assess railroad health or detect potential damage is a challenging *** to the large amount of data generated by DAS,as well as the unstructured patterns and substantial noise present,traditional analysis methods are ineffective in interpreting this *** paper introduces a novel approach that harnesses the power of deep learning through a combination of CNNs and LSTMs,augmented by sliding window techniques(CNN-LSTM-SW),to advance the state-of-the-art in the railroad condition monitoring *** well as it presents the potential for DAS and fiber optic sensing technologies to revolutionize the proposed CNN-LSTM-SW model to detect conditions along the rail track *** insights from the data of High tonnage load(HTL)-a 4.16 km fiber optic and DAS setup,we were able to distinguish train position,normal condition,and abnormal conditions along the ***,our investigation demonstrated that the proposed approaches could serve as efficient techniques for processing DAS signals and detecting the condition of railroad infrastructures at any remote distance with DAS-Fiber optic cable ***,in terms of pinpointing the train's position,the CNN-LSTM architecture showcased an impressive 97%detection *** a sliding window,the CNN-LSTM labeled data,the remaining 3%of misclassified labels have been improved dramatically by predicting the exact locations of each type of ***,these prop

关键词： Distributed acoustic sensing(DAS)-Fiber optic cable Railroad condition monitoring and anomaly detection High tonnage load(HTL) Convolutional neural network-long short-term memory-sliding window(CNN-LSTM-SW)

Engineering Nano/Microscale Chiral Self‑Assembly in 3D Printed Constructs

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Nano-Micro Letters 2024年第3期16卷 313-332页

作者： Mohsen Esmaeili Ehsan Akbari Kyle George Gelareh Rezvan Nader taheri‑Qazvini Monirosadat Sadati Department of Chemical Engineering University of South CarolinaColumbiaSC 29208USA TA Instruments Waters LLCNew CastleDE 19720USA Biomedical Engineering Program University of South CarolinaColumbiaSC 29208USA

Helical hierarchy found in biomolecules like cellulose,chitin,and collagen underpins the remarkable mechanical strength and vibrant colors observed in living *** study advances the integration of helical/chiral assembly and 3D printing technology,providing precise spatial control over chiral nano/microstructures of rod-shaped colloidal nanoparticles in intricate *** designed reactive chiral inks based on cellulose nanocrystal(CNC)suspensions and acrylamide monomers,enabling the chiral assembly at nano/microscale,beyond the resolution seen in printed *** employed a range of complementary techniques including Orthogonal Superposition rheometry and in situ rheo-optic measurements under steady shear rate *** techniques help us to understand the nature of the nonlinear flow behavior of the chiral inks,and directly probe the flow-induced microstructural dynamics and phase transitions at constant shear rates,as well as their post-flow ***,we analyzed the photo-curing process to identify key parameters affecting gelation kinetics and structural integrity of the printed object within the supporting *** insights into the interplay between the chiral inks self-assembly dynamics,3D printing flow kinematics and photopolymerization kinetics provide a roadmap to direct the out-of-equilibrium arrangement of CNC particles in the 3D printed filaments,ranging from uniform nematic to 3D concentric chiral structures with controlled pitch length,as well as random orientation of chiral *** biomimetic approach can pave the way for the creation of materials with superior mechanical properties or programable photonic responses that arise from 3D nano/microstructure and can be translated into larger scale 3D printed designs.

关键词： Directed chiral self-assembly Cellulose nanocrystals Bioinspired nanocomposite 3D printing Rheology

Targeting miRNA by CRISPR/Cas in cancer:advantages and challenges

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Military Medical Research 2024年第3期11卷 345-373页

作者： Bashdar Mahmud Hussen Mohammed Fatih Rasul Snur Rasool Abdullah Hazha Jamal Hidayat Goran Sedeeq Hama Faraj Fattma Abodi Ali abbas Salihi Aria Baniahmad Soudeh Ghafouri-Fard Milladur Rahman Mark C.Glassy Wojciech Branicki Mohammad taheri Department of Biomedical Sciences Cihan University-ErbilErbilKurdistan Region 44001Iraq Department of Clinical Analysis College of PharmacyHawler Medical UniversityErbilKurdistan Region 44001Iraq Department of Pharmaceutical Basic Science Faculty of PharmacyTishk International UniversityErbilKurdistan Region 44001Iraq Medical Laboratory Science Lebanese French UniversityErbilKurdistan Region 44001Iraq Department of Biology College of EducationSalahaddin University-ErbilErbilKurdistan Region 44001Iraq Department of Medical Laboratory Science Komar University of Science and TechnologySulaymaniyah 46001Iraq Department of Medical Microbiology College of Health SciencesHawler Medical UniversityErbilKurdistan Region 44001Iraq Department of Biology College of ScienceSalahaddin University-ErbilErbilKurdistan Region 44001Iraq Center of Research and Strategic Studies Lebanese French UniversityErbil 44001Iraq Institute of Human Genetics Jena University Hospital07747 JenaGermany Department of Medical Genetics School of MedicineShahid Beheshti University of Medical SciencesTehran 374-37515Iran Department of Clinical Sciences MalmöSection for SurgeryLund University22100 MalmöSweden Translational Neuro-Oncology Laboratory San Diego(UCSD)Moores Cancer CenterUniversity of CaliforniaSan DiegoCA 94720USA Faculty of Biology Institute of Zoology and Biomedical ResearchJagiellonian University31-007 KrakówPoland Urology and Nephrology Research Center Shahid Beheshti University of Medical SciencesTehran 374-37515Iran

Clustered regulatory interspaced short palindromic repeats(CRISPR)has changed biomedical research and provided entirely new models to analyze every aspect of biomedical sciences during the last *** the study of cancer,the CRISPR/CRISPR-associated protein(Cas)system opens new avenues into issues that were once unknown in our knowledge of the non-coding genome,tumor heterogeneity,and precision ***/Cas-based geneediting technology now allows for the precise and permanent targeting of mutations and provides an opportunity to target small non-coding RNAs such as microRNAs(miRNAs).However,the development of effective and safe cancer gene editing therapy is highly dependent on proper design to be innocuous to normal cells and prevent introducing other *** study aims to highlight the cutting-edge approaches in cancer-gene editing therapy based on the CRISPR/Cas technology to target miRNAs in cancer ***,we highlight the potential challenges in CRISPR/Cas-mediated miRNA gene editing and offer advanced strategies to overcome them.

关键词： CRISPR CRISPR/Cas9 CRISPR/Cas12 Gene editing miRNAs Cancer therapy

Classifying Modulations in Communication Intelligence Using Deep Learning Networks

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Journal of Systems Science and Information 2024年第3期12卷 379-392页

作者： Yahya BENREMDANE Said JAMAL Oumaima taheri Jawad LAKZIZ Said OUASKIT Department of Physics Faculty of Science Ben M'sikUniversity HassanⅡCasablanca 20100Morocco

The present research employs artificial intelligence to come up with an automatic solution for the modulation's classification of various radio signal *** a result,the work we performed involved selecting the database required for supervised deep learning,evaluating the performance of current techniques on unprocessed communication signals,and suggesting a deep learning networkbased method that would enable the classification of modulation types with the best possible ratio between computation time and *** started by examining the automatic classification models that are currently in *** light of the difficulty of forecasting in low Signal Noise Ratio(SNR)situations,we suggested an ensemble learning strategy based on adjusted Res Net and Transformer Neural Network,which is effective at extracting multi-scale features from the raw I/Q sequence ***,we produced an architecture that is simple to use and apply to communication *** architecture of this solution is strong and optimal,enabling it to determine the type of modulation with up to 95%accuracy automatically.

关键词： automatic modulation classification artificial intelligence deep learning radio frequency electronicwarfare