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investigation of material composition,design,and performance of open-graded asphalt mixtures for semi-flexible pavement:A comprehensive experimental study

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 92-116页

作者： mohammad Taghipoor Abolfazl Hassani mohammad m.Karimi Department of Civil and Environmental Engineering Tarbiat Modares UniversityTehranIran

The primary goal of this study is the design and construction of semi-flexible pavement(SFP)mixture in accordance with the engineering and mechanical criteria.This study involves the use of a range of gradation curves,air void contents,cellulose and synthesized fibers,and neat and modified asphalt binders to prepare the open-graded asphalt(OGA)mixtures.To analyze the characteristics of these mixtures,a variety of test,namely binder drainage,semi-circular bending(SCB),Cantabro,wheel tracking,indirect tensile strength(iTS),and permeability tests were conducted.Additionally,to analyze the prepared grouting material,flexural strength,compressive strength,and fluidity tests were conducted.in the final stage,SFP was compared to HmA in terms of engineering characteristics and performance.According to the results,SFP was more resistant to skid,rutting,fire,and moisture damage,while HmA had a better performance in fracture tests,including SCB test.According to the results of the mechanical performance tests conducted on OGA mixtures,the highest and lowest values for air void content to achieve the highest mechanical performance level were 30%-35%and 25%,respectively.Also,based on the laboratory results,it was determined that the required void ratio for constructing OGA mixtures was 24%-26%based on the bitumen type and fibers amount in the mixture.Finally,SFP mixture can be regarded as a viable alternative to common pavements thanks to its high resistance to rutting and moisture damage,long freezing-thawing fatigue life,and adequate fire and skid resistance.

关键词： Semi-flexible pavement mixture Open-graded asphalt mixture Engineering properties Cantabro test Hot mix asphalt

mediastinal emphysema in the context of perforated gastric ulcer

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World Journal of Clinical Cases 2024年第15期12卷 2479-2481页

作者： Debkumar chowdhury Department of Emergency medicine Wythenshawe HospitalManchester M239LTUnited Kingdom

in the context of mediastinal emphysema/pneumomediastinum,the main aetiologies are associated with oesophageal perforation,lung pathology or post head and neck surgery related.The main way to differentiate the pathologies would be through Computed Tomographic imaging of the Thorax and abdomen with oral and intravenous contrast in the context of triple phase imaging.The causes of pneumomediastinum should be differentiated between traumatic and non-traumatic.Oesophageal perforation(Boerhaave syndrome)is associated with mackler’s triad in upto 50%of patients(severe retrosternal chest pain,pneumomediastinum,mediastinitis).Whereas in cases of lung pathology this can be associated with pneumothorax and pleural effusion.

关键词： Pneumomediastinum Duodenal ulcer Computed tomography Visceral perforation Diagnostic imaging Emergency care

Design,simulation,and testing of a tunable mEmS multi-threshold inertial switch

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microsystems & Nanoengineering 2024年第2期10卷 37-46页

作者： Qiu Xu Rodrigo T.Rocha Yousef Algoos Eric Feron mohammad i.Younis Faculty of Electronic information Engineering Huaiyin Institute of TechnologyHuai’an223003PR China Computer Electrical and Mathematical Science and Engineering DivisionKing Abdullah University of Science and TechnologyThuwal23955-6900Saudi Arabia Piezoelectric microsystem Technologies Silicon Austria LabsVillach9524Austria Physical Sciences and Engineering Division King Abdullah University of Science and TechnologyThuwal23955Saudi Arabia mechanical Engineering Department State University of New YorkBinghamtonNY13902USA

This paper presents a tunable multi-threshold micro-electromechanical inertial switch with adjustable threshold capability.The demonstrated device combines the advantages of accelerometers in providing quantitative acceleration measurements and g-threshold switches in saving power when in the inactive state upon experiencing acceleration below the thresholds.The designed proof-of-concept device with two thresholds consists of a cantilever microbeam and two stationary electrodes placed at different positions in the sensing direction.The adjustable threshold capability and the effect of the shock duration on the threshold acceleration are analytically investigated using a nonlinear beam model.Results are shown for the relationships among the applied bias voltage,the duration of shock impact,and the tunable threshold.The fabricated prototypes are tested using a shock-table system.The analytical results agree with the experimental results.The designed device concept is very promising for the classification of the shock and impact loads in transportation and healthcare applications.

关键词： tunable acceleration testing

Post processing of additive manufactured mg alloys:Current status,challenges,and opportunities

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Journal of magnesium and Alloys 2024年第4期12卷 1283-1310页

作者： Nooruddin Ansari Fatima Ghassan Alabtah mohammad i.Albakri marwan Khraisheh mechanical Engineering Program Texas A&M University at QatarP.O.Box 23874DohaQatar

magnesium(mg)and its alloys are emerging as a structural material for the aerospace,automobile,and electronics industries,driven by the imperative of weight reduction.They are also drawing notable attention in the medical industries owing to their biodegradability and a lower elastic modulus comparable to bone.The ability to manufacture near-net shape products featuring intricate geometries has sparked huge interest in additive manufacturing(Am)of mg alloys,reflecting a transformation in the manufacturing sectors.However,Am of mg alloys presents more formidable challenges due to inherent properties,particularly susceptibility to oxidation,gas trapping,high thermal expansion coefficient,and low solidification temperature.This leads to defects such as porosity,lack of fusion,cracking,delamination,residual stresses,and inhomogeneity,ultimately influencing the mechanical,corrosion,and surface properties of Am mg alloys.To address these issues,post-processing of Am mg alloys are often needed to make them suitable for application.The present article reviews all post-processing techniques adapted for Am mg alloys to date,including heat treatment,hot isostatic pressing,friction stir processing,and surface peening.The utilization of these methods within the hybrid Am process,employing interlayer post-processing,is also discussed.Optimal post-processing conditions are reported,and their influence on the microstructure,mechanical,and corrosion properties are detailed.Additionally,future prospects and research directions are proposed.

关键词： magnesium alloy Additive manufacturing Post-processing Heat treatment HiP

A critical review towards the causes of the iron-based catalysts deactivation mechanisms in the selective oxidation of hydrogen sulfide to elemental sulfur from biogas

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Journal of Energy Chemistry 2024年第3期90卷 388-411,I0010页

作者： mostafa Tarek Janaina S.Santos Victor márquez mohammad Fereidooni mohammad Yazdanpanah Supareak Praserthdam Piyasan Praserthdam Center of Excellence on Catalysis and Catalytic Reaction Engineering(CECC) Department of Chemical EngineeringFaculty of EngineeringChulalongkorn UniversityBangkok 10330Thailan High-Performance Computing Unit(CECC-HCU) Center of Excellence on Catalysis and Catalytic Reaction Engineering(CECC)Chulalongkorn UniversityBangkok 10330Thailand

Hydrogen sulfide(H_(2)S) not only presents significant environmental concerns but also induces severe corrosion in industrial equipment,even at low concentrations.Among various technologies,the selective oxidation of hydrogen sulfide(SOH_(2)S) to elemental sulfur(S) has emerged as a sustainable and environmentally friendly solution.Due to its unique properties,iron oxide has been extensively investigated as a catalyst for SOH_(2)S;however,rapid deactivation has remained a significant drawback.The causes of iron oxide-based catalysts deactivation mechanisms in SOH_(2)S,including sulfur or sulfate deposition,the transformation of iron species,sintering and excessive oxygen vacancy formation,and active site loss,are thoroughly examined in this review.By focusing on the deactivation mechanisms,this review aims to provide valuable insights into enhancing the stability and efficiency of iron-based catalysts for SOH_(2)S.

关键词： Selective oxidation of H_(2)S iron-based Catalysts mechanism of deactivation Sulfur or sulfate deposition Transformation of iron species Sintering SDG 7

Ultrasensitive plasmonic sensor based on mDm waveguide containing Persian Orsi window cavities for refractive index and blood plasma sensing

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Optoelectronics Letters 2024年第7期20卷 406-411页

作者： mohammad Ghanavati mohammad Azim Karami School of Electrical Engineering Iran University of Science and Technology

We developed a plasmonic refractive index（Ri） with a metal-dielectric-metal（mDm） structure that utilizes two Persian Orsi windows-like separated cavities with a high figure of merit（Fom） and ultrasensitivity. The simulated and optimized Ag-air-Ag mDm sensor for surface plasmon resonance（SPR） offers high Ri sensitivity（SRi） and the ability to detect blood plasma concentration（BPC）. The results verified that structural parameters have an effect on SRi, full width at half maximum（FWHm）, Fom, sensitivity of blood plasma（Sp） for right and left peaks, whose values are 1 345.45 nm·RiU-1, 32 nm, 42.04 RiU-1, 0.26 and 0.19 nm·L·g-1, respectively. The proposed design opens a new horizon in sensor development.

关键词： A

Genotypic effects on accelerated propagation of oil palm breeding materials selected(Elaeis guineensis jacq.)using somatic embryogenesis

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Oil Crop Science 2024年第2期9卷 111-120页

作者： Retno Puji Astari mohammad Basyuni Luthfi A.m. Siregar Revandy i.m. Damanike Deni Arifiyanto Dadang Affandi indra Syahputra Doctoral Program of Agricultural Sciences Faculty of AgricultureUniversitas Sumatera UtaraMedan20155North SumatraIndonesia PT.Socfin indonesia Jl.K.L.Yos Sudarso No.106Medan20244North SumatraIndonesia Department of Forestry Faculty of ForestryUniversitas Sumatera UtaraJl.Tri Dharma Ujung No.1Medan20155North SumatraIndonesia Center of Excellence for mangrove Universitas Sumatera UtaraMedan20155Indonesia Department of Agrotechnology Faculty of AgricultureUniversitas Sumatera UtaraMedan20155North SumatraIndonesia

Vegetable oil production from oil palm(Elaeis guineensis Jacq.)is an important industry due to the rising demand every year.The somatic embryogenesis culture can propagate oil palm duplicate as parent plant,which can be selected as breeding material to produce new planting germplasm with high production or disease resistance.This study aims to evaluate the genotypic effect of somatic embryogenesis,while immature leaflets were employed as explants.The culture used embryo induction medium based on murashige and Skoog(mS)modifications that contained 5 mg/L Naphthalene Acetic acid(NAA)and 0.5 mg/L Benzyl Amino Purine(BAP).The genotypic effect was statistically significant in the percentage of callus induction,producing somatic embryos,and germination embryos.in this study,we successfully cloned thirteen oil palm genotypes(GE-02,GE-03,GE-06,GE-07,GE-09,GE-23,GE-24,GE-27,GE-28,GE-32,GE-33,GE-34,and GE-35),with the highest number of somatic embryos formed on GE-27 with a percentage of 70.1%.The cloning was successful in accelerating the propagation of oil palm for materials breeding programs to create new varieties with high production and disease resistance.it is necessary to observation the performance of these clones in the field in terms of mantle flower appearance.

关键词： Somatic embryogenesis Oil palm Genotypic effect Support breeding

Recent Progress in Bionic Hydrogels for Articular Cartilage:Tribological and mechanical Characteristics

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Journal of Bionic Engineering 2024年第2期21卷 653-673页

作者： mohammad Javan Almasi Dangsheng Xiong School of materials Science and Engineering Nanjing University of Science and TechnologyNanjing210094China

Cartilage regeneration and repair are considered clinical challenges since cartilage has limited capability for reconstruction.Although tissue-engineered materials have the ability to repair cartilage,they have weak mechanical characteristics and cannot resist long-term overload.On the other hand,surgery to replace the joint is frequently done to treat significant cartilage deterioration these days.However,the materials that are being used for replacement have high friction coefficients,lack shock absorption functions,and lack cushioning.Further research on natural articular cartilage structure and function may lead to bionic hydrogels,which have suitable physicochemical and biological characteristics(e.g.,tribological and mechanical properties and the ability to support loadbearing capability),but need improvements.Based on their tribological and mechanical characteristics,the current review highlights the most recent advancements of bionic hydrogels used for articular cartilage,highlighting both the field's recent progress and its potential for future research.For this reason,firstly,some important property improvement methods of bionic hydrogels are discussed and then,the recent findings of various research on the making of those bionic materials are provided and compared.it seems that by using some modifications such as product design,surface treatments,animal tests,controlling the isoelectric point of hydrogels,and computer simulation,the intended mechanical and tribological characteristics of natural articular cartilage may be attained by the bionic hydrogels.

关键词： Bionic hydrogel Articular cartilage mechanical property Tribological property Lubrication

Sacrificial piles as a countermeasure against local scour around underwater pipelines

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Water Science and Engineering 2024年第2期17卷 187-196页

作者： Forough Raeisi Seyed mohammad Ali Zomorodiann masih Zolghadr Hazi mohammad Azamathulla Department of Water Engineering Shiraz UniversityShiraz ***Iran Department of Water Sciences Engineering Jahrom UniversityJahrom ***Iran Department of Civil and Environmental Engineering The University of the West IndiesSt.Augustine CampusTrinidad 331310Republic of Trinidad and Tobago

Local scour around pipelines crossing rivers or in marine environments is a significant concern.it can lead to failure of the pipelines resulting in environmental side effects and economic losses.This study developed an experimental method to reduce local scour around pipelines with a steady flow of clear water by installing cylindrical and cubical sacrificial piles.Three sizes of sacrificial piles were examined in a linear arrangement.Sacrificial piles were installed on the upstream side of the pipeline at three distances.maximum scour depth reduction rates below the pipeline were computed.The results showed that sacrificial piles could protect a pipeline from local scour.A portion of scoured sediment around the sacrificial piles was deposited beneath the pipeline.This sediment accumulation reduced the scour depth beneath the pipeline.Analysis of the experimental results demonstrated that the size of piles(d),the spacing between piles,and the distance between the pipe and piles(Xp)were the variables that reduced the maximum scour beneath the pipeline with a diameter of D.For the piles with d=0.40D and 0.64D,X_(p)=4OD was the optimal distance to install a group of piles,and cubical piles could mitigate scour more effectively than cylindrical piles under similar conditions.For the piles with d=D,the greatest reduction in scour depth was achieved at X_(p)=50D with any desired spacings between piles,and cylindrical piles in this dimension could protect the pipeline against scour more effectively than cubical piles.

关键词： Clear water River crossing pipeline Local scour Self-burial process Sediment transport