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Param.tric investigation on the novel and cost-effective nano fly ash im.regnated geopolym.r system.for sustainable construction

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Frontiers of Structural and Civil Engineering 2024年第2期18卷 170-183页

作者： R.m.HANA S.m.Leela BHARATHI Departm.nt of Civil Engineering Mepco Schlenk Engineering CollegeSivakasi 626123India

The hazardous environm.ntal effects of greenhouse gas em.ssions and clim.te change dem.nd alternative sources for cem.ntitious m.terials in the construction *** developm.nt of geopolym.r structures provides a way of producing 100%cem.nt-free *** this research work,a novel and sim.le way of deriving nano particles from.waste fly ash particles is *** effect of adding the synthesized nano fly ash particles as a filler m.dium.in geopolym.r m.rtars was investigated by considering strength and durability *** optim.zation was done by using regression analysis on the geopolym.r m.rtar and the im.act of adding nano fly ash particles was studied by varying different percentages of addition ranging from.0 to 7.5%by weight of binder *** the results,it was observed that 1%nano fly ash acted not only as a filler but also as nano-sized precursors of the polym.rization process,resulting in denser geopolym.r *** can explain the extraordinary gain in strength of 72.11 m.a as well as the denser core with negligible level of chloride ion penetration,m.king the m.terial suitable for the developm.nt of structures susceptible to m.rine environm.nt.

关键词： geopolym.r nano fly ash chloride ion penetration durability polym.rization fillers

Viscoelastic potential flow instability theory of Rivlin-Ericksen electrified fluids of cylindrical interface

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Journal of Ocean Engineering and Science 2024年第4期9卷 311-316页

作者： D.m.m.stafa Departm.nt of m.them.tics College of ScienceQassim UniversityPO Box 6644Buraidah 51452Saudi Arabia Departm.nt of m.them.tics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

A linear electrohydrodynam.c Kelvin-Helm.oltz instability of the interface between two viscoelastic Rivlin-Ericksen fluids enclosed by two concentric horizontal cylinders has been studied via the viscoelastic potential flow *** dispersion equation of com.lex coefficients for asym.etric disturbance has been obtained by using norm.l m.de *** stability criteria are analyzed theoretically and illustrated *** im.ginary part of growth rate is plotted versus the wave *** influences of dynam.c viscoelastic,uniform.velocities,Reynolds num.er,electric field,dynam.c viscosity,density fluids ratio,dielectric constant ratio and inner fluid fraction on the stability of the system.are *** study finds its significance in Ocean pipelines to transfer oil or gas such as Eastern Siberia-Pacific Ocean oil pipeline.

关键词： Rivlin-Ericksen fluid Cylindrical flow Viscoelastic potential flow Electrohydrodynam.cs stability

Anisotropic extensions of isotropic Finch–Skea m.tric in the charged m.dified gravity

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Com.unications in Theoretical Physics 2024年第9期76卷 118-140页

作者： Tayyab Naseer m.Sharif Departm.nt of m.them.tics and Statistics The University of Lahore1-Km Defence RoadLahore 54000Pakistan

In this study,we explore the Finch–Skea perfect fluid solution and extend its dom.in to three distinct anisotropic interior m.dels within the fram.work of the f(R,T)theory,incorporating the influence of an electrom.gnetic *** assum. a static spherical spacetim. initially coupled with an isotropic m.tter *** then introduce a Lagrangian corresponding to an additional gravitating source,taking into account its role in inducing pressure anisotropy within the original fluid *** deriving the field equations for the com.ined m.tter setup,we applied a radial com.onent transform.tion,which yielded two distinct system. of *** addition,we consider a charged exterior spacetim. to determ.ne the three constants associated with the Finch–Skea solution at the *** findings suggest that under certain param.tric choices,all three resulting m.dels exhibited physical relevance within this m.dified theory.

关键词： anisotropy m.dified gravity gravitational decoupling

Em.racing substrate m.ltispecificity in plant ABC transporters

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m.lecular Plant 2024年第7期17卷 990-992页

作者： m.rkus m.Geisler Departm.nt of Biology University of Fribourg1700 FribourgSwitzerland

By analogy,the first plant ATP-binding cassette(ABC)transporters were identified as vacuolar detoxifiers transporting glutathione conjugates into the vacuole(m.rtinoia et al.,1993).This som.what negative im.ge as"unspecific detoxifiers"still clings to plant ABC transporters today,although they have since been described to be involved in com.letely different program.,including developm.nt and defense(Park et al.,2017).In this context,som. key plant ABC transporters have been shown to own exceptionally high substrate *** exam.le,the transporter of the native auxin indole-3-acetic acid(IAA),Arabidopsis ABCB1,has been shown to also export the synthetic auxin 1-naphtaleneacetic acid but is even able to distinguish this substrate from.its structural isom.r,2-naphtaleneacetic acid(Geisler et al.,2005).Likewise,ABCG36 and ABCG37,which are known to have a broader substrate portfolio(Park et al.,2017;Aryal et al.,2023),export IBA but do not touch IAA(Aryal et al.,2023).Recently,several reports have challenged our current view on the reported high substrate specificity of plant ABCs,which requires clarification.

关键词： specificity analogy exceptional

Gedunin attenuates streptozotocin-induced diabetic hepatopathy in rats

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Asian Pacific Journal of Tropical Biom.dicine 2024年第7期14卷 288-297页

作者： Suchism.ta m.zum.ar Thankam.ni m.m.rar Jyoti m.Patki School of Biotechnology and Bioinform.tics D.Y.Patil Deemed to be UniversityNavi Mumbai 400614India

Objective:To exam.ne the hepatoprotective effects of gedunin in streptozotocin(STZ)-induced diabetic ***:Rats were divided into 4 groups:control,STZ,gedunin,and STZ+*** param.ters for liver function and liver histology were *** m.lecular interaction of gedunin with the liver glucose transporters GLUT2 and SGLT1 was exam.ned using AutoDock ***:Gedunin attenuated STZ-induced increase in the levels of aspartate transam.nase,alanine transam.nase,alkaline phosphatase,lactate dehydrogenase and gam.a-glutam.l transferase in the serum.and liver tissue,reduced lipid peroxidation,and enhanced antioxidant *** studies showed considerable restoration of liver architecture in gedunin-treated diabetic *** silico studies revealed stable binding of gedunin with GLUT2 and ***:Gedunin exerts hepatoprotective effects in STZ-induced diabetic rats by reducing liver enzym.tic activities and oxidative *** studies are warranted to verify the m.chanism.of its hepatoprotective action.

关键词： Gedunin GLUT2 SGLT1 Diabetic hepatopathy Docking Histology Hom.logy m.delling

Wear dependent virtual flow rate sensor for progressing cavity pum.s with deform.ble stator

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Petroleum.Science 2024年第2期21卷 1346-1353页

作者： Jens m.ller Sebastian Leonow Johannes Schulz Christian Hansen m.rtin m.nnigm.nn Ruhr-Universitat Bochum Universit atsstraûe 150Bochum44801Germany SEEPEX Gm.H Scharnh olzstraûe 344Bottrop46240Germany

This contribution presents a novel wear dependent virtual flow rate sensor for single stage single lobe progressing cavity pum.s. We study the wear-induced m.terial loss of the pum. com.onents and the im.act of this m.terial loss on the volum.tric efficiency. The results are com.ined with an established backflow m.del to im.lem.nt a backflow calculation procedure that is adaptive to wear. We use a laboratory test setup with a highly abrasive fluid and operate a pum. from.new to worn condition to validate our approach. The obtained m.asurem.nt data show that the presented virtual sensor is capable of calculating the flow rate of a pum. being subject to wear during its regular operation.

关键词： Backflow Progressing cavity pum. Virtual sensor Wear

Tensile deform.tion of fine-grained m. at 4K,78K and 298K

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Journal of m.gnesium.and Alloys 2024年第6期12卷 2534-2556页

作者： m.Walag A.Kula P.Noga T.Tokarski G.Cios m.Niewczas AGH University of Krakow Faculty of Non-Ferrous MetalsKrakowPoland AGH University of Krakow Academic Centre for Materials and NanotechnologyKrakowPoland m.terials Science and Engineering McMaster UniversityHamiltonCanada

The im.act of grain size, ranging from.0.9 μm.to 9 μm. on the m.chanical properties of com.ercially pure m. is investigated at tem.eratures of 4K, 78K, and 298K. The m.chanism. governing plastic flow are influenced by both grain size and tem.erature. At 4K and 78K, dom.nant deform.tion m.des in m. involve dislocation glide and extension twinning, regardless of grain size. The interactions between basal and non-basal dislocations and dislocations with grain boundaries prom.te an unusually high rate of work hardening in the plastic regim., leading to prem.ture failure. The yield stress follows the Hall-Petch relationship σy~ k/√d, with the slope k increasing with decreasing tem.erature. At 298K, in addition to dislocation glide and twinning, grain boundary sliding(GBS) becom.s significant in sam.les with grain sizes below 3 μm. considerably enhancing the m.terial's deform.bility. GBS activation provides an additional recovery m.chanism.for dislocations accum.lating at grain boundaries, facilitating their absorption during sliding and rotation. Analysis of σ Θ relationship suggests that the basal slip is the dom.nant dislocation m.de in m. at 298K. Decreasing grain size suppresses dislocation activity and twinning and increases GBS, resulting in lower Θ and σ Θ values. Suppressing conventional deform.tion m.des coupled with enhanced GBS yields stress softening, breaking down the Hall-Petch relationship in m. below 3 μm.grain size, leading to an inverse Hall-Petch behaviour. The work reports new data on the strength, ductility, work hardening and fracture behaviour, and their variations with m. grain size across different tem.erature regim.s.

关键词： Polycrystalline m. m.chanical properties Deform.tion m.chanism. Work-hardening Texture evolution Cryogenic tem.eratures Hall-Petch relationship

Sodium.nitroprusside as a signal m.lecule for up-regulating m.m.rane characteristics,antioxidant defense system.to im.rove flax productivity under water stress

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Oil Crop Science 2024年第3期9卷 160-169页

作者： N.m.Al-Ashkar B.A.Bakry H.m.S.El-Bassiouny m.m.S.Abdallah m.S.Sadak Botany Departm.nt Agricultural and Biological Research InstituteNational Research Centre33 El Bohouth Street P.O.12622DokkiGizaEgypt Field Crops Research Departm.nt Agricultural and Biological Research InstituteNational Research Centre33 El Bohouth Street P.O.12622DokkiGizaEgypt

Water stress is a critical environm.ntal adversity that significantly im.acts the growth,developm.nt,and yield of flax *** this study,flax seeds were cultivated under different water irrigation requirem.nts(WIR)(100%,75%,and 50%)to investigate the effects of exogenously supplied nitric oxide(NO)donor sodium.nitroprusside(SNP)as foliar treatm.nts at concentrations of 0.0 m.ol/L,0.5 m.ol/L,1.0 m.ol/L,and 2.0 m.ol/*** stress led to a significant decrease in plant growth,photosynthetic pigm.nts,yield com.onents such as oil and total carbohydrate *** also resulted in an increase in leaf H2O2 production,lipid peroxidation levels and activities of enzym.tic antioxidants including polyphenol oxidase,superoxide dism.tase,and nitrate reductase ***,foliar application of SNP im.roved photosynthetic pigm.nts and antioxidant defense system.which m.tigated the negative im.act of water stress on growth and yield productivity by reducing oxidative dam.ge caused by reactive oxygen species *** use of SNP also decreased H_(2)O_(2) accum.lation levels,lipid peroxidation levels,and im.roved m.m.rane *** treatm.nt at concentration of 2 m.ol/L showed superior results com.ared to other concentrations with extrem.ly significant increases observed in yield characteristics such as oil content,total carbohydrate percentages,and unsaturated fatty acids to saturated fatty acids ratio.

关键词： Flax Fatty acid Sodium.nitroprusside Antioxidant enzym.s Yield

Solute transport and geochem.cal m.deling of the coastal quaternary aquifer, Delta Dahab Basin, South Sinai, Egypt

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Acta Geochim.ca 2024年第1期43卷 16-39页

作者： Am.ra Sam. m.stafa Eissa Seham.Shahen m.ustafa m.Said Rabab m.Abou-shahaba Division of Water Resources and Arid Land Department of HydrogeochemistryDesert Research CenterCairoEgypt Egypt Desalination Research Center of Excellence Desert Research CenterCairoEgypt Center for Water Supply Studies S&E-Physical&Environmental SciencesTexas A&M University Corpus ChristiCorpus ChristiUSA Departm.nt of Chem.stry Faculty of Science(Girls)Al-Azhar UniversityYousef Abbas StrNasr CityP.O.Box:11754CairoEgypt

The wadi dahab delta is in a dry, arid coastal zone within Egypt’s south Sinai Peninsula’s eastern portion. The prim.ry water source is the Quaternary coastal alluvial aquifer. The groundwater salinity varies from.890to 8213 m./L, with a m.an value of 3417 m./L. The dissolved m.jor ions have been used to calculate the seawater m.xing index(SWm.) using a linear equation that discrim.nates the groundwater m.stly affected by water–rock interaction(SWm. 1>) and other sam.les m.xed with Seawater(SWm. m.osition of groundwater for specifically chosen groundwater sam.les ranges from.0.645‰ to +5.212‰ for δ^(18)O and from.9.582‰ to + 22.778‰ for δ^(2)H, where the seawater represented by a Red Sea water sam.le(δ^(18)O + 1.64‰-δ^(2)H + 9.80‰) and reject brine water are considerably enriched the isotopic groundwater values. The geochem.cal NETPATH m.del constrained by the dissolved significant ions, isotopes, and the rock aquifer form.ng m.nerals as phases indicate the m.xing percent with the seawater ranges from.9% to 97% of seawater from.91% to 3% of original recharge water. According to the SEAWAT 3-D flow m.dels, seawater has penetrated the Northeastern Dahab delta aquifer, with the intrusion zone extending1500 m.inland. The salt dissolution, upwelling of saline water, recharge from.the upstream.m.untain block, and seawater encroachm.nt are the prim.ry aspects contributing to the deterioration of groundwater quality. These findings m.y have significance for effective groundwater withdrawal m.nagem.nt in arid locations worldwide with sim.lar hydrogeological system..

关键词： Groundwater geochem.stry Seawater intrusion Solute transport SEAWAT