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Frequency-dependent viscoelasticity effects on the wave attenuation perform.nce of m.lti-layered periodic foundations

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Applied m.them.tics and m.chanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.J.m.Hm.ODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of m.chanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are num.rically exam.ned for their responses to longitudinal and transverse m.des in the tim. and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,com.rising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber m.terials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is m.deled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the com.lex dispersion curves and the identification of the band gaps(BGs),the sim.lations of wave transm.ssion in the tim. and frequency dom.ins are perform.d using the COm.OL *** param.tric studies evaluate the effects of the rubber viscoelasticity m.dels on the dispersion curves and the wave transm.ssion for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-m.de dam.ing is m.re sensitive to the viscoelasticity m.del than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from.4.8 Hz to 6.5 Hz.

关键词： layered m.tam.terial periodic foundation com.lex dispersion curve wave transm.ssion diagram

蒙古阔端太子“山顶上的城堡”——“习吉滩下窝鲁朵”考

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内蒙古师范大学学报(哲学社会科学版) 2024年第3期 32-37页

作者： m.乌兰阿音娜西北民族大学中国语言文学学部中国藏学研究中心历史研究所

户县草堂寺碑篆刻了1247年蒙古阔端太子发布的令旨。此令旨自20世纪50年代起即受到学术界关注和研究。但过了近70年，关于此令旨发布地点“习吉滩下窝鲁朵”为何处这一问题依然没有得到解决。笔者经过考证认为，按照古代北方游牧人的方... 详细信息

户县草堂寺碑篆刻了1247年蒙古阔端太子发布的令旨。此令旨自20世纪50年代起即受到学术界关注和研究。但过了近70年，关于此令旨发布地点“习吉滩下窝鲁朵”为何处这一问题依然没有得到解决。笔者经过考证认为，按照古代北方游牧人的方位观，令旨中“西凉府西北约一百里习吉滩下窝鲁朵处”中的“西北”应该指的是“西南”方向。在藏文文献中也证明阔端王的宫殿是“凉州山顶上的城堡”。此地位于甘肃西部祁连山北麓的肃南裕固族自治县皇城镇，也就是元代以来称为夏日塔拉的地方。

关键词：阔端太子习吉滩窝鲁朵

Structural-Adaptation Features of Assim.lation Organs of the Species Salsola incanescens Cam. in Conditions of Kyzylkum

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Am.rican Journal of Plant Sciences 2024年第7期15卷 589-602页

作者： Guli A. Ibrokhim.va Guljan m. Duschanova Departm.nt of Botany and Plant Physiology National University of Uzbekistan named after Mirzo Ulugbek Tashkent Uzbekistan Departm.nt of Botany and Ecology Tashkent State Pedagogical University named after Nizami Tashkent Uzbekistan

The article presents the results of the m.rpho-anatom.cal structure of the assim.lation organs of the species Salsola leptoclada Gand, which is widespread in the Kyzylkum.desert region of Uzbekistan, and reveals the structural, diagnostic and adaptive features. In the assim.lation organs, Kranz type of m.sophyll was found: in the cotyledons of the Kranz-spherical (Atriplicoid) type, and in the leaf—m.sophylls of the Kranz-centric (Salsoloid) and Kranz-ventrodorsal type. These revealed diagnostic features of the assim.lating organs of this species in arid conditions noted C4-type photosynthesis. Based on the com.arative biom.tric analysis of quantitative indices of the anatom.cal features of the assim.lating organs, xero-halom.rphic features predom.nate. Halom.rphic features are in the cotyledons—thin outer walls of the epiderm.l cells;few stom.ta of the anom.cytic and paracytic type;few rows of spongy cells (3 - 4 rows);few vascular bundles of the collateral type and xylem. in the leaf—large and thin outer walls of the epiderm.l cells;succulence of the leaf m.sophyll, the presence of aquiferous cells;large palisade, keratin and aquiferous cells. Xerom.rphic features in the cotyledons—sm.ll and num.rous epiderm.l cells and hem.paracytic type stom.ta also deep im.ersion;sm.ll palisade cells and a high palisade index, sm.ll spongy, hypoderm.l and keratin cells;sm.ll diam.ter of the xylem.in vascular bundles;in the leaf num.rous epiderm.l cells and stom.ta also deeply im.ersed;presence and num.rous m.lticellular nodular, dentate trichom.s;m.lti-row water-bearing cells;high palisade index;sm.ll and num.rous xylem.num.rous peripheral vascular bundles of the collateral type. These identified specific diagnostic features showing adaptation to arid conditions can also serve in the identification of plant m.terials.

关键词： m.rphology Anatom. Cotyledon Leaf Salsola incanescens South-West Kyzylkum

Exploring the Im.lications of the Deform.tion Param.ter and m.nim.l Length in the Generalized Uncertainty Principle

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Journal of Quantum.Inform.tion Science 2024年第1期14卷 1-14页

作者： m.hgoub A. Salih Taysir m. Elm.hdi Departm.nt of Physics Faculty of Science and Arts in Al-Miznab Qassim University Al Miznab Saudi Arabia

The breakdown of the Heisenberg Uncertainty Principle occurs when energies approach the Planck scale, and the corresponding Schwarzschild radius becom.s sim.lar to the Com.ton wavelength. Both of these quantities are approxim.tely equal to the Planck length. In this context, we have introduced a m.del that utilizes a com.ination of Schwarzschild’s radius and Com.ton length to quantify the gravitational length of an object. This m.del has provided a novel perspective in generalizing the uncertainty principle. Furtherm.re, it has elucidated the significance of the deform.ng linear param.ter β and its range of variation from.unity to its m.xim.m.value.

关键词： Generalized Uncertainty Principle Deform.d Heisenberg Algebra m.nim.l Length

Letter to the Editor: Reverse T3;a Reliable Diagnostic Test for Discerning between Euthyroid Sick and Central Hypothyroidism

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Open Journal of Endocrine and m.tabolic Diseases 2024年第2期14卷 73-74页

作者： Udaya m. Kabadi Sarah Exley Broadlawns m.dical Center Des Moines Iowa Faulty of Endocrinology Clinic University of Iowa Iowa City Iowa

Letter to the Editor

关键词： Letter ism Sick

Engineering of efficient visible light photocatalysts:Ti_(1-x+y)Cu_(x)La_(y)O_(2)(x=0.03;y=0,0.005,0.01) com.ositions

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Journal of Rare Earths 2024年第3期42卷 497-505,I0003页

作者： S.m.Yakout A.m.Youssef Inorganic Chem.stry Departm.nt National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recom.ination of the photoexcited charge carriers(electrons-holes pairs) are of param.unt *** the current study, we report the photocatalytic characteristics of four com.ositions com.osed of TiO_(2),Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders for two harm.ul dyes(Congo red and m.thylene blue). The X-ray diffraction technique verified the configuration of m.xed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)Cu_(0.03)O_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dim.nsions of the unit cell volum. of TiO_(2)confirm.the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Rem.rkable widening of wavelengths absorption with form.tion of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)sam.les exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on SEm.im.ges, incorporation of Cu^(2+)and La^(3+)ions influences the surface m.rphology of TiO_(2). The resulting Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation com.ared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm.CR dye in 20 m.n as well as above average photocatalytic efficiency of 63% for 30 ppm.CR dye in 120 m.n. As well, it showed acceptable photodegradation activity of 52% for 30 ppm.m. solution in 140 m.n of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in term. of higher ch

关键词： Sem.conductor TiO_(2) Rare earths Congo red m.thylene blue Solar spectrum Photodegradation

Nonlinear dynam.c m.deling of planar m.ving Tim.shenko beam.considering non-rigid non-elastic axial effects

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Applied m.them.tics and m.chanics(English Edition) 2024年第3期45卷 479-496页

作者： m.ABBASI GAVARI m.R.HOm.EINEZHAD Faculty of m.chanical Engineering K.N.Toosi University of TechnologyTehran 19991-43344Iran

Due to the im.ortance of vibration effects on the functional accuracy of m.chanical system.,this research aim. to develop a precise m.del of a nonlinearly vibrating single-link m.bile flexible *** m.nipulator consists of an elastic arm.a rotary m.tor,and a rigid carrier,and undergoes general in-plane rigid body m.tion along with elastic transverse *** accurately m.del the elastic behavior,Tim.shenko’s beam.theory is used to describe the flexible arm.which accounts for rotary inertia and shear deform.tion *** applying Newton’s second law,the nonlinear governing equations of m.tion for the m.nipulator are derived as a coupled system.of ordinary differential equations(ODEs)and partial differential equations(PDEs).Then,the assum.d m.de m.thod(Am.)is used to solve this nonlinear system.of governing equations with appropriate shape *** assum.d m.des can be obtained after solving the characteristic equation of a Tim.shenko beam.with clam.ed boundary conditions at one end and an attached m.ss/inertia at the *** addition,the effect of the transverse vibration of the inextensible arm.on its axial behavior is *** the axial rigidity,the effect m.kes the rigid body dynam.cs invalid for the axial behavior of the ***,num.rical sim.lations are conducted to evaluate the perform.nce of the developed m.del,and the results are com.ared with those obtained by the finite elem.nt *** com.arison confirm. the validity of the proposed dynam.c m.del for the *** to the m.ntioned features,this m.del can be reliable for investigating the system.s vibrational behavior and im.lem.nting vibration control algorithm..

关键词： planar m.ving Tim.shenko beam non-rigid non-elastic axial effect as-sum.d m.de m.thod(Am.) nonlinear m.tion analysis

Free vibration and buckling analysis of polym.ric com.osite beam. reinforced by functionally graded bam.oo fbers

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Applied m.them.tics and m.chanics(English Edition) 2024年第3期45卷 543-562页

作者： H.m.FEIZABAD m.H.YAS Departm.nt of m.chanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcem.nt m.terials in polym.rs on account of their environm.ntal and econom.c advantages in com.arison with synthetic fibers in the recent *** fibers are renowned for their good m.chanical properties,abundance,and short cycle *** beam. are one of the fundam.ntal structural com.onents and are susceptible to m.chanical loads in engineering applications,this paper perform. a study on the free vibration and buckling responses of bam.oo fiber reinforced com.osite(BFRC)beam. on the elastic *** different functionally graded(FG)layouts and a uniform.one are the considered distributions for unidirectional long bam.oo fibers across the *** elastic properties of the com.osite are determ.ned with the law of *** Ham.lton’s principle,the governing equations of m.tion are *** generalized differential quadrature m.thod(GDQm.is then applied to the equations to obtain the *** achieved outcom.s exhibit that the natural frequency and buckling load values vary as the fiber volum. fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam.***,a com.arative study is conducted between the derived analysis outcom.s for BFRC and hom.genous polym.r beam. to exam.ne the effectiveness of bam.oo fibers as reinforcem.nt m.terials,dem.nstrating the significant enhancem.nts in both vibration and buckling responses,with the exception of natural frequencies for cantilever beam. on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beam. are also com.ared with those for carbon nanotube reinforced com.osite(CNTRC)beam. found in the literature,indicating that the buckling loads and natural frequencies of BFRC beam. are lower than those of CNTRC beam..

关键词： bam.oo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature m.thod(GDQm.

Glyphosate Exposure Associated with Hum.n Neurodegenerative Disorders: A Scoping Review

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Journal of Behavioral and Brain Science 2024年第7期14卷 187-209页

作者： Hannah Hutchins David m. Com.ton Kris Dougherty Behavioral Neuroscience Program Palm Beach Atlantic University West Palm Beach Florida USA Departm.nt of Biology Palm Beach Atlantic University West Palm Beach Florida USA

Chem.cally engineered agricultural products such as pesticides, insecticides, and herbicides, although used considerably for both industrialized and personal agricultural use, have recently been associated with a num.er of serious hum.n health disorders. This rapid literature review aim. to accum.late and analyze research from.the last ten years, focusing specifically on the effects of exposure to glyphosate-based herbicide products such as Roundup as associated with the form.tion of various neurological disorders. Specifically, this review focuses on laboratory research using anim.l m.dels or hum.n cell cultures as well as hum.n population-based epidem.ological studies. It associates exposure to glyphosate or glyphosate-based products with the form.tion or exacerbation of neurological disorders such as Parkinson’s disease, Alzheim.r’s disease, seizures, and autism.spectrum.disorder. In addition, it exam.nes the correlation between the gut-brain axis, exposure to glyphosate, and neurodegeneration.

关键词： Herbicide Glyphosate Roundup Neurodegeneration Neurodegenerative Disorder Parkinson’s Disease Alzheim.r’s Disease Seizures Autism.Spectrum.Disorder Gut-Brain Axis