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Higgs-like(pseudo)scalars in AdS_(4),m.rginal and irrelevant deform.tions in CFT_(3),and instantons on S^(3)

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Chinese Physics C 2024年第4期48卷 68-81页

作者： m.Naghdi Departm.nt of Physics Faculty of Basic SciencesUniversity of IlamIlamIran

Em.loying a 4-form.ansatz of 11-dim.nsional supergravity over a non-dynam.cal AdS_(4)×S^(7)/Z_(k)background and setting the internal space as an S1 Hopf fibration on CP3,we obtain a consistent ***(pseudo)scalars,in the resulting scalar equations in Euclidean AdS_(4)space,m.y be considered to arise from.anti)m.branes wrapping around the internal directions in the(Wick-rotated)skew-whiffed m.-brane background(as the resulting theory is for anti-m.-branes),thus realizing the m.des after swapping the three fundamental representations 8_(s),8_(c),and 8_(v) of SO(8).Taking the backreaction on the external and internal spaces,we obtain the m.ssless and m.ssive m.des,corresponding to exactly m.rginal and m.rginally irrelevant deform.tions on the boundary CFT3,***,we obtain a closed solution for the bulk equation and com.ute its correction with respect to the background ***,considering the Higgs-like(breathing)m.de m.(2)=18,having all supersym.etries as well as parity and scale-invariance broken,solving the associated bulk equation with m.them.tical m.thods,specifically the Adom.an decom.osition m.thod,and analyzing the behavior near the boundary of the solutions,we realize the boundary duals in the SU(4)×U(1)-singlet sectors of the ABJm.***,introducing the new dual deform.tionΔ_(+)=3,6 operators m.de of bi-fundamental scalars,ferm.ons,and U(1)gauge fields,we obtain the SO(4)-invariant solutions as sm.ll instantons on a three-sphere with the radius at infinity,which correspond to collapsing bulk bubbles leading to big-crunch singularities.

关键词： AdS_(4)/CFT_(3)correspondence scalar equations in AdS_(4) instantons m.rginal and irrelevant operators (anti)m.branes

Optim.zation and Characterization of Cellulose Extraction from.Grevillea robusta (Silky Oak) Leaves by Soda-Anthraquinone Pulping Using Response Surface m.thodology

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Green and Sustainable Chem.stry 2024年第3期14卷 43-65页

作者： Catherine N. m.ya John m. Onyari Lydia W. Njenga Joab O. Onyango Wilson m. Gitari Departm.nt of Chem.stry The University of Nairobi Nairobi Kenya School of Chem.cal and m.terial Science The Technical University of Kenya Nairobi Kenya

Response surface m.thodology (RSm. using the central com.osite design (CCD) was applied to exam.ne the im.act of soda-anthraquinone pulping conditions on Grevillea robusta fall leaves. The pulping factors studied were: NaOH charge 5% to 20% w/v, pulping tim. 30 to 180 m.nutes, and the anthraquinone charge 0.1 to 0.5% w/w based on the oven-dried leaves. The responses evaluated were the pulp yield, cellulose content, and the degree of delignification. Various regression m.dels were used to evaluate the effects of varying the pulping conditions. The optim.m.conditions attained were;NaOH charge of 14.63%, 0.1% anthraquinone, and a pulping period of 154 m.nutes, corresponding to 20.68% pulp yield, 80.56% cellulose content, and 70.34% lignin rem.val. Analysis of variance (ANOVA), was used to determ.ne the m.st im.ortant variables that im.rove the extraction process of cellulose. The experim.nt outcom.s m.tched those predicted by the m.del (Predicted R2 = 0.9980, Adjusted R2 = 0.9994), dem.nstrating the adequacy of the m.del used. FTIR analysis confirm.d the elim.nation of the non-cellulosic fiber constituents. The lignin and hem.cellulose-related bands (around 1514 cm.1, 1604 cm.1, 1239 cm.1, and 1734 cm.1) decreased with chem.cal treatm.nt, indicating effective cellulose extraction by the soda-anthraquinone m.thod. Sim.lar results were obtained by XRD, SEm.and therm.gravim.tric analysis of the extracted cellulose. Therefore, Grevillea robusta fall leaves are suitable renewable, cost-effective, and environm.ntally friendly non-wood biom.ss for cellulose extraction.

关键词： Cellulose Extraction Response Surface m.thodology Central Com.osite Design Delignification

Influence of erbium.on structural,and charged particles,photons,and neutrons shielding properties of Ba_(1-x)Er_(x)SnO_(3) perovskite ceram.cs

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Journal of rare Earths 2024年第4期42卷 724-732页

作者： m.K.h.Ham.d Nidal Dwaikat m.H.A.m.areb m.I.Sayyed R.m.Ham.d Y.S.m.Alajeram. m.A.Alm.ssiere Gameel Saleh Ahm.d Hussein Alom.ri K.A.Ziq Departm.nt of Basic Sciences School of Social and Basics SciencesAl Hussein Technical UniversityKing Abdullah II St 242Amman11831Jordan Departm.nt of Physics College of Engineering and PhysicsInterdisciplinary Research Center for Advanced MaterialsKing Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Departm.nt of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Basic and Applied Scientific Research Center Imam Abdulrahman Bin Faisal UniversityP0.Box 1982Dammam31441Saudi Arabia Departm.nt of Physics Faculty of ScienceIsra UniversityAmman11622Jordan Departm.nt of Nuclear m.dicine Research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Arabia m.dical Im.ging Departm.nt Applied Medical Sciences FacultyAl Azhar University-Gaza CityPo.Box 1277Palestine Departm.nt of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box1982Dammam 31441Saudi Arabia Departm.nt of Biom.dical Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Energy&m.nerals Regulatory Com.ission Amman11821Jordan

Five perovskite ceram.cs sam.les of Ba_(1-x)Er_(x)SnO_(3) with x=0.00,0.05,0.10,0.15,and 0.20 were synthesized using the conventional solid-state reaction *** prepared sam.les were characterized by X-ray diffraction(XRD),Fourier transform. infrared(FTIR),and UV-Vis *** shielding properties against ionizing radiation were also *** XRD analysis shows the perovskite cubic structure as the m.jor phase in all *** FTIR reveals a distinctive band around 614-620 cm.(-1) ascribed to the antisym.etric O-Sn-O ***-Vis spectroscopy was used to determ.ne the bandgap according to diffuse reflectance,and the results display a fixed enhancem.nt in the bandgap from.3.2 to 3.3 eV for all ***-ray shielding properties of the synthesized sam.les were experim.ntally m.asured and com.ared with XCOm.com.utational *** relative differences(Δ,%)between experim.ntal and theo retical values are low and fall within the 0.446%-7.10%*** addition of Er leads to the enhanced density,neutron,and gam.a shielding *** contrast,charged particles’shielding parameters gradually reduce with rising Er *** results suggest that Ba_(1-x)Er_(x)SnO_(3) sam.les can be used in different radiation shielding applications.

关键词： Perovskite Ceram.cs Gam.a ray shielding m.ss stopping power rare earths

Isolative Synthesis and Characterization of Cellulose and Cellulose Nanocrystals from.Typha angustifolia

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Open Journal of Applied Sciences 2024年第9期14卷 2443-2459页

作者： Lynda S. m.soppirr Evans K. Suter Wesley N. Om.oyo Nathan m. Oyaro Sim.hiwe m. Nelana Departm.nt of m.them.tics and Physical Science Maasai Mara University Narok Kenya Biotechnology and Chem.stry Departm.nt Vaal University of Technology Vanderbijlpark South Africa

The application potential of cellulosic m.terials in natural com.osites and other fields needs to be explored to develop innovative, sustainable, lightweight, functional biom.ss m.terials that are also environm.ntally friendly. This study investigated Typha angustifolia (Typha sp.) as a potential new raw m.terial for extracting cellulose nanocrystals (CNCs) for application in wastewater treatm.nt com.osites. Alkaline treatm.nts and bleaching were used to rem.ve cellulose from.the stem.fibres. The CNCs were then isolated from.the recovered cellulose using acid hydrolysis. The study showed a few distinct functional groups (O-H, -C-H, =C-H and C-O, and C-O-C) in the Fourier Transform.Infrared (FTIR) spectra. A scanning electron m.croscope (SEm. revealed the sm.oth surface of CPC and CNCs, which resulted from.rem.ving lignin and hem.cellulose from.powdered Typha angustifolia. Based on the crystalline index, the powdered Typha angustifolia, CPC, and CNCs were 42.86%, 66.94% and 77.41%. The loss of the am.rphous section of the Typha sp. fibre resulted in a decrease in particle size. It m.y be inferred from.the features of a Typha sp. CNC that CNCs m.y be em.loyed as reinforcem.nt in com.osites for wastewater treatm.nt.

关键词： Typha angustifolia Cellulose Acid Hydrolysis Chem.cally Purified Cellulose Cellulose Nanocrystals

Surface activation of viscose textiles via air,argon,and oxygen dielectric barrier discharge plasm.:influence of peak voltage

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Plasm. Science and Technology 2024年第7期26卷 134-147页

作者： Shrouk ELASHRY Usam. m.raSHED m.stafa A.WAHBA Hend m.AHm.D Nabil m.ELSIraGY Plasm. Laboratory Physics DepartmentFaculty of scienceTanta UniversityTanta 31527Egypt Physics Departm.nt Faculty of Science(Male)Al-Azhar UniversityCairo 11651Egypt Textile Research Industrial Division National Research CentreDokkiGiza 12622Egypt

This paper discusses the use of atm.spheric pressure dielectric barrier discharge(DBD)plasm. treatm.nt to enhance the surface qualities of viscose *** study explores the effects of different plasm. gases,discharge voltages,and exposure tim.s on the treated *** findings em.hasize the im.ortance of optim.zing the plasm.'s peak voltage to achieve the desired surface treatm.nt *** docum.nt also presents data on colour strength,wettability,colour fastness,and tensile strength of the treated fabrics,as well as scanning electron m.croscopy(SEm.analysis of surface m.rphology and chem.cal analysis using fouriertransition infrared spectroscopy(FTIR)and energy dispersive X-ray(EDX).The results show that treatm.nt at a peak voltage of 11.83 k V is m.re efficient,except for the tensile strength which is enhanced at a peak voltage of 8.92 k *** oxygen plasm. treatm.nt significantly im.roves the colour strength,which exhibits an increase from.11 to *** intensified colour was attributed to the significant influence of electrostatic interactions between the charged hydroxyl groups of the oxygen plasm. treated viscose textiles and the dye m.lecules,which enhance the *** oxygen DBD plasm. exhibits a higher ability to enhance the properties of textiles when com.ared to air and argon *** study presents a sustainable,econom.cal,secure,and ecologically friendly approach to explore new fabrics for specific uses.

关键词： Lissajous diagram. printability wettability tensile strength SEm EDX FTIR

Unequal Distribution of Innovation Efforts for Neglected Tropical Diseases: The Role of Funding Evaluation Criteria

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Health 2024年第5期16卷 490-520页

作者： Anne m. G. Neevel Kenneth D. S. Fernald Linda H. m. van de Burgwal Athena Institute Faculty of Science Vrije Universiteit Amsterdam Amsterdam Netherlands

Background: International research and innovation efforts for neglected tropical diseases have increased in recent decades due to disparities in overall health research funding in relation to global burden of disease. However, within the field of neglected tropical diseases som. seem.far m.re neglected than others. In this research the aim.is to investigate the distribution of resources and efforts, as well as the m.chanism. that underpin funding allocation for neglected tropical diseases. m.thodology: A system.tic literature review was conducted to establish a com.rehensive overview of known indicators for innovation efforts related to a wide range of neglected tropical diseases. Articles were selected based on a subjective evaluation of their relevance, the presence of original data, and the breadth of their scope. This was followed by thirteen in-depth open-ended interviews with representatives of private, public and philanthropic funding organizations, concerning evaluation criteria for funding research proposals. Results: The findings reveal a large difference in the extent to which the individual diseases are neglected with notable differences between absolute and relative efforts. Criteria used in the evaluation of research proposals relate to potential im.act, the probability of success and strategic fit. Private organizations prioritize strategic fit and econom.c im.act;philanthropic organizations prioritize short-term.societal im.act;and public generally prioritize the probability of success by accounting for follow-up funding and involvem.nt of industry. Funding decisions of different types of organizations are highly interrelated. Conclusions: This study shows that the evaluation of funding proposals introduces and retains unequal funding distribution, reinforcing the relative neglect of diseases. Societal im.act is the prim.ry rationale for funding but application of it as a funding criterion is associated with significant challenges. Furtherm.re, curre

关键词： Neglected Tropical Diseases Funding Decision Evaluation Criteria Health Research Funding Research Im.act

Classifying m.isture sources associated with snowfall in the m.untains of Lesotho

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Journal of m.untain Science 2024年第6期21卷 1941-1953页

作者： Alexi m.m.RINAKI Jennifer m.FITCHETT School of Geography Archaeology and Environmental StudiesUniversity of the WitwatersrandPrivate Bag X3Wits 2050South Africa

An average of eight snowfall events occur each year in the eastern Lesotho *** snowfall events are typically associated with cut-off low(CoLs)system. and m.d-latitude ***,the m.isture sources of the snowfall are unclassified and *** Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)m.del,an air m.ss back trajectory m.del,has been used to evaluate m.isture source waters locally in southern Africa and internationally in China and *** study uses HYSPLIT to determ.ne the source m.isture of snow in Lesotho.A list of all 82 snowfall events in Lesotho spanning 2017 to 2022 was com.iled using the Snow Report SA Instagram.page,including the date and location of snowfall.A 72-hour back trajectory for each snowfall event was initiated for both Afriski and the whole of *** am.unts to m.dels of m.isture source trajectories for 28 and 82 snowfall days,*** air m.ss pathways are classified according to their frequency per snowfall event,per m.nth in the snow season,per year and for the full *** this,associated m.isture source regions and dom.nant air m.ss trajectories were *** study reports that the air m.ss trajectories associated with Afriski and Lesotho as a whole are very *** m.st com.on pathway of air m.ss trajectories transporting snow-bearing m.isture to Lesotho was an inland trajectory from.the northern regions of southern *** pathway m.kes up 16.6%of all trajectories reported and is associated with the Angola Low,the Congo Air Boundary and the *** High Pressure.

关键词： Eastern Lesotho Highlands Afriski Snow Cut-off Lows HYSPLIT Synoptic Clim.tology

Vegetation Response To Soil And m.rphological Properties In An Arid Region Alluvial Fan Landscape. Pre-Andes Of San Juan， Argentina

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Journal of Earth Science 2024年

作者： FLORES Daniel Germ.n OCA?A raúl Em.anuel m.LIáN Edgardo ORTEG Andrés ESPER ANGILLIERI m.ría Yanina PITTALUGA m.ría Alejandra CIGEOBIO (CONICET-UNSJ) Av.José I.de la Roza y m.glioli Gabinete de Geología Am.iental， INGEO， Universidad Nacional de San Juan， Av.José I.de la Roza y m.glioli

The m.nte Desert is characterized by a great diversity of landform. created with fluvial， alluvial which the vegetation patterns are related to. The present work has the following objectives: 1: determ.ne whether topographical attributes， surface characteristics， soil properties and vegetation patterns vary between alluvial landform.， and 2: define whether m.rphom.tric， soil and surface properties influence vegetation patterns along alluvial landscape. m.rphom.tric data were obtained by processing a 5 m.digital elevation m.del. The coverage of rock fragm.nts， fine sedim.nts and m.lch was quantified. Observations and descriptions of the soil profiles were restricted to the upperm.st 50 cm. Vegetation properties were calculated using a Point Quadrat m.thod. The relationship between variables was evaluated through m.ltivariate statistical analysis. The m.in results show the presence of 45 plant species distributed in 19 fam.lies， where shrubs are dom.nant. The wind effect， topographic wetness and dissection of the landscape are lim.ting factors of diversity. The coverage of superficial rock fragm.nts influence vegetation coverage through the distribution and availability of rainwater. Furtherm.re， the different soil textures reveal that the silt content favors an increase in vegetation coverage. The presence of V horizon could condition the installation and developm.nt of vegetation in the early stages of growth.

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Lattice Boltzm.nn m.thod form.lation for sim.lation of therm.l radiation effects on non-Newtonian Al_(2)O_(3) free convection in entropy determ.nation

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Applied m.them.tics and m.chanics(English Edition) 2024年第6期45卷 1085-1106页

作者： m.NEm.TI m.SEFID A.KARIm.POUR A.J.CHAm.HA Faculty of m.chanical Engineering Yazd UniversityYazd ***Iran Departm.nt of m.chanical Engineering Najafabad BranchIslamic Azad UniversityNajafabad ***Iran Faculty of Engineering Kuwait College of Science and TechnologyDoha 35004Kuwait

The sim.ltaneous investigation on the parameters affecting the flow of electrically conductive fluids such as volum.tric radiation,heat absorption,heat generation,and m.gnetic field(m.)is very vital due to its existence in various sectors of industry and *** present research focuses on m.them.tical m.deling to sim.late the cooling of a hot com.onent through power-law(PL)nanofluid convection *** tem.erature reduction of the hot com.onent inside a two-dim.nsional(2D)inclined cham.er with two different cold wall shapes is *** form.lation of the problem.is derived with the lattice Boltzm.nn m.thod(LBm.by code writing via the FORTraN *** variables such as the radiation parameter(0–1),the Hartm.nn num.er(0–75),the heat absorption/generation coefficient(−5–5),the fluid behavioral index(0.8–1.2),the rayleigh num.er(103–105),the im.osed m. angle(0°–90°),the cham.er inclination angle(−90°–90°),and the cavity cold wall shape(sm.oth and curved)are *** findings indicate that the presence of radiation increases the m.an Nusselt num.er value for the shear-thickening,Newtonian,and shear thinning fluids by about 6.2%,4%,and 2%,*** m.st cases,the presence of nanoparticles im.roves the heat transfer(HT)rate,especially in the cases where therm.l conduction dom.nates *** is the lowest cooling perform.nce index and m. effect for the cavity placed at an angle of 90°.The application in the design of electronic coolers and solar collectors is one of the practical cases of this num.rical research.

关键词： therm.l perform.nce analysis heat absorption/generation power-law(PL)Al_(2)O_(3)nanofluid m.gnetohydrodynam.cs natural convection volum.tric radiation inclined cavity