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earthquake engineering and engineering Vibration 2024年第3期23卷 713-726页

作者： m.A.Najafgholipour s.Heidarian Radbakhsh e.erfani Department of Civil and environmental engineering Shiraz University of TechnologyShiraz ***Iran Department of Building Civiland Environmental EngineeringConcordia UniversityMontréal H3G 1M8Canada

This paper presents an investigation of the seismic behavior of reinforced concrete(RC)structures in which shear walls are the main lateral load-resisting elements and the participation of flat slab floor systems is not considered in the seismic design *** this regard,the behavior of six prototype structures(with different heights and plan layouts)is investigated through nonlinear static and time history analyses,implemented in the Opensees *** results of the analyses are presented in terms of the behavior of the slab-column connections and their mode of failure at different loading ***,the global response of the buildings is discussed in terms of some parameters,such as lateral overstrength due to the gravity flat slab-column *** to the nonlinear static analyses,in structures in which the slab-column connections were designed only for gravity loads,the slab-column connections exhibited a punching mode of failure even in the early stages of ***,the punching failure was eliminated in structures in which a minimum transverse reinforcement recommended in ACI 318(2019)was provided in the slabs at joint ***,despite neglecting the contribution of gravity flat slab-column frames in the lateral load resistance of the structures,a relatively significant overstrength was imposed on the structures by the gravity frames.

关键词： RC flat slab-column frames seismic behavior nonlinear analysis time history analysis

swift XRT Analysis of Type II-P supernova sN 2008ij

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International Journal of Astronomy and Astrophysics 2024年第3期14卷 220-229页

作者： sh. m. shehata Ahmed m. Fouad R. m. samir A. A. shaker National Research Institute of Astronomy and Geophysics (NRIAG) Helwan Egypt

This study investigates the X-ray properties and evolution of Type II supernovae (sNe II) observed by swift, examining variations among supernovae and exploring their X-ray characteristics over time. We present the first X-ray study of the Type IIp supernova sN 2008ij using data from the swift X-ray mission. This investigation focuses on its spectral properties, identifying an X-ray flux of 1.20 (+0.11, −0.10) × 10−13 erg/cm2/s and a plasma temperature of 4.76 (+1.22, −0.83) keV. Our study marks an advancement in understanding sN 2008ij, providing crucial results into its X-ray emission characteristics. These results lay the groundwork for future studies of Type IIp supernovae, offering a foundation for exploring their evolutionary and physical processes.

关键词： X-Ray Core Collapse supernova swift (XRT) Observations

Fuel cell stack design and modelling with a double-stage boost converter coupled to a single-phase inverter

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Clean energy 2024年第1期8卷 188-196页

作者： Basem e.elnagi Ahmed m.Ismaiel Hany s.e.mansour m.N.Abd-Alwahab electrical engineering Department Faculty of EngineeringSuez Canal UniversityIsmailia 41522Egypt

A comprehensive proton-exchange membrane fuel cell stack model was developed and integrated with a two-stage DC/DC boost *** was directly coupled to a single-phase(two levels-four pulses)inverter without a *** pulse-width modu-lation signal was used to independently regulate every converter *** converter was modelled using a mATLAB®/simulink®environment and an appropriate voltage control *** analysis features of the suggested circuit were created and,through established experiments,the simulation results were verified.A single-phase(two levels-four pulses)inverter control circuit was tested and it produced a pure sinusoidal waveform with voltage *** matches the voltage of the network in terms of amplitude and frequency.A sinusoidal pulse-width modulation approach was performed using a single-phase(two levels-four pulses)pulse-width modulation *** results demonstrated an enhancement in the standard of the output wave and tuned the dead time with a reduction of 63μs compared with 180μs in conventional techniques.

关键词： Pem fuel cell pulse-width modulation single-phase inverter and double-stage DC/DC boost converter

magneto-Photo-Thermoelastic excitation Rotating semiconductor medium Based on moisture Diffusivity

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Computer modeling in engineering & sciences 2024年第10期141卷 107-126页

作者： Khaled Lotfy A.m.s.mahdy Alaa A.el-Bary e.s.elidy Department of mathematics Faculty of ScienceZagazig UniversityZagazig44519Egypt Department of mathematics Faculty of ScienceTaibah UniversityMadinah42353Saudi Arabia Department of mathematics and statistics College of ScienceTaif UniversityTaif11099Saudi Arabia Arab Academy for science Technology and Maritime TransportAlexandria1029Egypt

In this research,we focus on the free-surface deformation of a one-dimensional elastic semiconductor medium as a function of magnetic field and moisture *** problem aims to analyze the interconnection between plasma and moisture diffusivity processes,as well as thermo-elastic *** study examines the photothermoelasticity transport process while considering the impact of moisture *** employing Laplace’s transformation technique,we derive the governing equations of the photo-thermo-elastic *** equations include the equations for carrier density,elastic waves,moisture transport,heat conduction,and constitutive *** stresses,thermal conditions,and plasma boundary conditions are used to calculate the fundamental physical parameters in the Laplace *** employing numerical techniques,the Laplace transform is inverted to get complete time-domain solutions for the primary physical domains under ***,thermoelastic,and thermoelectric characteristics are employed in conjunction with a graphical analysis that takes into consideration the effects of applied forces on displacement,moisture concentration,carrier density,stress due to forces,and temperature distribution.

关键词： moisture diffusivity semiconductor photothermoelastic rotation thermomechanical waves laplace transform

Nonlinear wave dispersion in monoatomic chains with lumped and distributed masses:discrete and continuum models

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Applied mathematics and mechanics(english edition) 2024年第4期45卷 633-648页

作者： e.GHAVANLOO s.eL-BORGI school of mechanical engineering Shiraz UniversityShiraz 71963-16548Iran mechanical engineering Program Texas A&M University at QatarDoha 23874Qatar

The main objective of this paper is to investigate the influence of inertia of nonlinear springs on the dispersion behavior of discrete monoatomic chains with lumped and distributed *** developed model can represent the wave propagation problem in a non-homogeneous material consisting of heavy inclusions embedded in a *** inclusions are idealized by lumped masses,and the matrix between adjacent inclusions is modeled by a nonlinear spring with distributed ***,the model is capable of depicting the wave propagation in bi-material bars,wherein the first material is represented by a rigid particle and the second one is represented by a nonlinear spring with distributed *** discrete model of the nonlinear monoatomic chain with lumped and distributed masses is first considered,and a closed-form expression of the dispersion relation is obtained by the second-order Lindstedt-Poincare method(LPm).Next,a continuum model for the nonlinear monoatomic chain is derived directly from its discrete lattice model by a suitable continualization *** subsequent use of the second-order method of multiple scales(mms)facilitates the derivation of the corresponding nonlinear dispersion relation in a closed *** novelties of the present study consist of(i)considering the inertia of nonlinear springs on the dispersion behavior of the discrete mass-spring chains;(ii)developing the second-order LPm for the wave propagation in the discrete chains;and(iii)deriving a continuum model for the nonlinear monoatomic chains with lumped and distributed ***,a parametric study is conducted to examine the effects of the design parameters and the distributed spring mass on the nonlinear dispersion relations and phase velocities obtained from both the discrete and continuum *** parameters include the ratio of the spring mass to the lumped mass,the nonlinear stiffness coefficient of the spring,and the wave amplitude.

关键词： nonlinear mass-spring chain discrete model continuum model LindstedtPoincare method(LPm) method of multiple scales(mms) dispersion phase velocity

Kriging-boosted CR modeling for prompt infill drilling optimization

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Petroleum 2024年第1期10卷 39-48页

作者： elizaveta s.Gladchenko Anna e.Gubanova Denis m.Orlov Dmitry A.Koroteev skolkovo Institute of science and Technology Russian Federation Digital Petroleum LLC Russian Federation

The capacitance-resistance model(CRm)has been a useful physics-based tool for obtaining production forecasts for ***,the model's limitations make it difficult to work with real field cases,where a lot of various events *** events often include new well commissioning(NWC).We introduce a workflow that combines CRm concepts and kriging into a single tool to handle these types of events during history ***,it can be used for selecting a new well placement during infill *** make the workflow even more versatile,an improved version of CRm was *** takes into account wells shut-ins and performed workovers by additional adjustment of the model *** preliminary re-weighing and interpolating these coefficients using kriging,the coefficients for potential wells can be *** approach was validated using both synthetic and real datasets,from which the cases of putting new wells into operation were *** workflow allows a fast assessment of future well performance with a minimal set of reservoir *** way,a lot of well placement scenarios can be considered,and the best ones could be chosen for more detailed studies.

关键词： Capacitance-resistance model(CRm) Field development optimization Infill drilling Interwell connectivity Kriging New well commissioning(NWC)

Investigation of the transformation of organic matter of carbonate deposits of the semiluksky-mendymsky horizon under hydrothermal conditions

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Petroleum 2024年第2期10卷 216-223页

作者： s.m.Petrov A.I.Lakhova e.G.moiseeva A.G.safiulina Institute of Petroleum Chemistry and NanotechnologiesKazan National Research Technological UniversityKazan420015Russia Institute of Geology and Oil and Gas Technologies Kazan Federal UniversityKazan420008Russia

The paper presents the results of studies on the transformation of the organic matter of siliceous-clayey carbonate rocks of the semiluksko-mendymsky horizon of the Romashkino oil field in a hydrothermal fluid for an hour(with a water-to-rock ratio of 33)at 340℃and 380℃and pressu res of 17 and 20 *** a result of hydrothermal treatment,at 340℃and 17 mPa,based on nitrogen porosimetry and electron microscopy data,transformations of rock-forming minerals in the rock are *** lead to an increase in the volume and average diameter of mesopores in it and the formation of micropores,as well,which improve its filtration *** the same time,the amount of kerogen in the composition of the organic matter decreases and the yield of the petroleum hydrocarbon extract increases,in which,according to the sARA analysis,the content of asphaltenes increases and the content of resins,aromatic and saturated hydrocarbons *** the composition of aroatic hydrocarbons,the proportion of a lkyltri methyl benzenes and dibenzothiophenes increases,phenanthrene homologues appear,and in the composition of saturated hydrocarbons,the amount of iso-structure alkanes decreases relative to the content of linear *** the temperature and pressure of the hydrothermal fluid to 380℃and 20 mPa increases the degree of kerogen conversion from 12.4%to 23.6%.At the same time,changes occurring in the component composition of petroleum hydrocarbon extracts remains similar to the experiments carried out at 340℃and 17 mPa;the content of naphthalenes decreases,the content of dibenzothiophenes increases and C_(11)-C_(17),C_(19)-C_(22)alkyltrimethylbenzenes *** to IR spectroscopy,with increasing temperature and pressure of the hydrothermal fluid the intensity of the absorption bands of the aromatic ring,aliphatic fragments,and oxygen-containing groups increases in resins;the structural-group composition of asphaltenes changes little:aromaticity and the content of conde

关键词： Carbonate deposits Organic matter Hydrothermal fluid mobile hydrocarbons

Nanomotion of bacteria to determine metabolic profile

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Nanotechnology and Precision engineering 2024年第1期7卷 1-9页

作者： s.N.Pleskova e.V.Lazarenko N.A.Bezrukov R.N.Kriukov A.V.Boryakov m.e.Dokukin s.I.surodin Research Laboratory of scanning Probe microscopy Lobachevsky State University of Nizhny NovgorodNizhny Novgorod 603950Russia Department of Nanotechnology and Biotechnology Nizhny Novgorod State Technical University n.a.R.E.AlekseevNizhny Novgorod 603950Russia sarov Physics and Technology Institute National Research Nuclear University MEPhISarov 607186Russia

In addition to their visible motion such as swimming(e.g.,with the help ofﬂagella),bacteria can also exhibit nanomotion that is detectable only with highly sensitive instruments,and this study shows that it is possible to detect bacterial nanomotion using an AFm detection *** results show that the nanomotion characteristics depend on the bacterial strain,and that nanomotion can be used to sense the metabolic activity of bacteria because the oscillations are sensitive to the food preferences of the bacteria and the type of surrounding medium.

关键词： Nanomotion Bacteria Cantilever Oscillation Atomic force microscopy metabolism

Transcriptional reprogramming during human osteoclast differentiation identifies regulators of osteoclast activity

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Bone Research 2024年第1期12卷 180-198页

作者： morten s.Hansen Kaja madsen maria Price Kent søe Yasunori Omata mario m.Zaiss Caroline m.Gorvin morten Frost Alexander Rauch molecular endocrinology Laboratory(KmeB) Department of EndocrinologyOdense University HospitalDK-5000 Odense CDenmark Department of Clinical Research Faculty of Health SciencesUniversity of Southern DenmarkDK-5000 Odense CDenmark Clinical Cell Biology Pathology Research UnitDepartment of Clinical ResearchUniversity of Southern DenmarkDK-5000 Odense CDenmark Institute of metabolism and systems Research(ImsR)and Centre for Diabetes Endocrinology and Metabolism(CEDAM)University of BirminghamBirmingham B152TTUK Centre for membrane Proteins and Receptors(COmPARe) Universities of Birmingham and NottinghamBirmingham B152TTUK Department of molecular medicine University of Southern DenmarkDK-5000 Odense CDenmark Department of Orthopedic surgery Faculty of MedicineThe University of TokyoTokyo 113-8655Japan Department of Internal medicine 3 Rheumatology and ImmunologyFriedrich-Alexander-University Erlangen-Nürnberg(FAU)and Universitätsklinikum ErlangenD-91054 ErlangenGermany Deutsches Zentrum Immuntherapie(DZI) Friedrich-Alexander-University Erlangen-Nürnberg and Universitätsklinikum ErlangenD-91054 ErlangenGermany steno Diabetes Center Odense Odense University HospitalDK-5000 Odense CDenmark

enhanced osteoclastogenesis and osteoclast activity contribute to the development of osteoporosis,which is characterized by increased bone resorption and inadequate bone *** novel antiosteoporotic therapeutics are needed,understanding the genetic regulation of human osteoclastogenesis could help identify potential treatment *** study aimed to provide an overview of transcriptional reprogramming during human osteoclast *** were differentiated from CD14+monocytes from eight female *** sequencing during differentiation revealed 8980 differentially expressed genes grouped into eight temporal patterns conserved across *** patterns revealed distinct molecular functions associated with postmenopausal osteoporosis susceptibility genes based on RNA from iliac crest biopsies and bone mineral density *** analyses revealed mutual dependencies between temporal expression patterns and provided insight into subtype-specific transcriptional *** donor-specific expression patterns revealed genes at the monocyte stage,such as filamin B(FLNB)and oxidized low-density lipoprotein receptor 1(OLR1,encoding LOX-1),that are predictive of the resorptive activity of mature *** expression of differentially expressed G-protein coupled receptors was strong during osteoclast differentiation,and these receptors are associated with bone mineral density sNPs,suggesting that they play a pivotal role in osteoclast differentiation and *** regulatory effects of three differentially expressed G-protein coupled receptors were exemplified by in vitro pharmacological modulation of complement 5 A receptor 1(C5AR1),somatostatin receptor 2(ssTR2),and free fatty acid receptor 4(FFAR4/GPR120).Activating C5AR1 enhanced osteoclast formation,while activating ssTR2 decreased the resorptive activity of mature osteoclasts,and activating FFAR4 decreased both the number and resorptive activity of mature *** conclus

关键词： osteoclast programming identif

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) compositions

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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 Chemistry Department National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount *** the current study, we report the photocatalytic characteristics of four compositions composed 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 harmful dyes(Congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed 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 dimensions of the unit cell volume of TiO_(2)confirm the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation 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)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on sem images, incorporation of Cu^(2+)and La^(3+)ions influences the surface morphology 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 compared 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 min as well as above average photocatalytic efficiency of 63% for 30 ppm CR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm mB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in terms of higher ch

关键词： semiconductor TiO_(2) Rare earths Congo red methylene blue solar spectrum Photodegradation