检索结果-南通市图书馆

Chinese physics B 2024年第9期33卷 433-442页

作者： Kaixuan li Cheng Ning Ye Dong Chuang Xue Institute of Applied physics and Computational Mathematics Beijing 100088China

For investigating efficiently the stagnation kinetic-process of z-pinch,we develop a novel modified electrostatic implicit particle-in-cell algorithm in radial one-dimension for z-pinch simulation in which a small-angle cumulative binary collision algorithm is *** our algorithm,the electric field in z-direction is solved by a parallel electrode-plate model,the azimuthal magnetic field is obtained by Ampere’s law,and the term for charged particle gyromotion is approximated by the cross product of the averaged velocity and magnetic *** simulation results of 2 MA deuterium plasma shell zpinch,the mass-center implosion trajectory agrees generally with that obtained by one-dimensional MHD simulation,and the plasma current also closely aligns with the external *** phase space diagrams and radial-velocity probability distributions of ions and electrons are *** main kinetic characteristic of electron motion is thermal equilibrium and oscillation,which should be oscillated around the ions,while that of ion motion is implosion *** the region of stagnation radius,the radial-velocity probability distribution of ions transits from the non-equilibrium to equilibrium state with the current increasing,while of electrons is basically the equilibrium *** the initial ion density and current peak are not high enough,the ions may not reach their thermal equilibrium state through collisions even in its stagnation phase.

关键词： z-pinch particle-in-cell ion heating charged particle collisions

Effects of multiple shapes for steady flow with transformer oil+Fe_(3)O_(4)+TiO_(2) between two stretchable rotating disks

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 373-388页

作者： M.RAHMAN M.TURKYILMAzOGLU z.MUSHTAQ Department of Mathematics Mirpur University of Science and TechnologyMirpur 10250Pakistan Department of Mathematics Hacettepe UniversityBeytepeAnkara 06532Turkiye

In this study,we examine the effects of various shapes of nanoparticles in a steady flow of hybrid nanofluids between two stretchable rotating *** steady flow of hybrid nanofluids with transformer oil as the base fluid and Fe_(3)O_(4)+TiO_(2)as the hybrid nanofluid is *** shapes of Fe_(3)O_(4)+TiO_(2)hybrid nanofluids,including sphere,brick,blade,cylinder,and platelet,are *** shape exists in the same volume of a *** leading equations(partial differential equations(pDEs))are transformed to the nonlinear ordinary differential equations(ODEs)with the help of similarity *** system of equations takes the form of ODEs depending on the boundary conditions,whose solutions are computed numerically by the bvp4c MATLAB *** outputs are compared with the previous findings,and an intriguing pattern is discovered,such that the tangential velocity is increased for the rotation parameter,while it is decreased by the stretching values because of the lower *** the reaction rate parameter,the concentration boundary layer becomes shorter,and the activation energy component increases the rate at which mass transfers come to the higher disk but have the opposite effect on the bottom *** ranges of various parameters taken into account are pr=6.2,Re=2,M=1.0,φ_(1)=φ_(2)=0.03,K=0.5,S=-0.1,Br=0.3,Sc=2.0,α_(1)=0.2,γ=0.1,E_(n)=2.0,and q=1.0,and the rotation factor K is within the range of 0 to 1.

关键词： transformer oil Brinkman number skin friction coefficient double rotating disk Nusselt number Sherwood number

Four Late-type Galaxies with Double Radio Lobes and properties of Such Galaxies

在线全文

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第4期24卷 84-90页

作者： z.S.Yuan X.Y.Gao z.L.Wen J.L.Han National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAS Key Laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China

The triggering mechanism for radio lobes from late-type galaxies is not fully *** samples are desired for a thorough investigation and *** utilizing the optical data from the newly released Dark Energy Spectroscopic Instrument imaging surveys and the radio sources from the NRAO VLA Sky Survey and the Faint Images of the Radio Sky at Twenty-centimeter,we identify four Late-type Galaxies with double Radio Lobes(La GRLs):J0217-3645,J0947+6220,J1412+3723 and J1736+*** previously known La GRLs,we confirm the correlation between radio power p_(1.4GHz)and stellar mass M_(*)of host ***(25/35)La GRLs belong to the blue cloud galaxies,while the newly identified cases in this work are located within the region of the red *** find a clear correlation between the differential radio power,i.e.,the offset from the p_(1.4GHz)-M_(*)relation,and the galaxy color,indicating that bluer galaxies at a fixed M_(*)tend to host more powerful radio ***,the majority(31/36)of La GRLs are either located in a galaxy group or displaying a disturbed *** suggest that all of the galaxy mass,color and surrounding environment could play important roles in triggering radio lobes in late-type galaxies.

关键词： galaxies:active galaxies:jets galaxies:spiral radio continuum:galaxies

phosphorylation promotes the Accumulation of pERIOD protein Foci

在线全文

学校读者我要写书评

暂无评论

Research 2024年第1期2023卷 59-69页

作者： Mengna li Shujing li Luoying zhang Key Laboratory of Molecular Biophysics of Ministry of Education College of Life Science and TechnologyHuazhong University of Science and TechnologyWuhanHubei 430074China Department of life Sciences Bengbu Medical CollegeBengbuAnhui 233030China Hubei province Key Laboratory of Oral and Maxillofacial Development and Regeneration WuhanHubei 430022China

Circadian clock drives the 24-h rhythm in our behavior and *** molecular clock consists of a series of transcriptional/translational feedback loops operated by a number of clock genes.A very recent study reported that the clock protein pERIOD(pER)is organized into discrete foci at the nuclear envelope in fly circadian neurons,which is believed to be important for controlling the subcellular localization of clock *** of inner nuclear membrane protein lamin B receptor(LBR)leads to disruption of these foci,but how they are regulated is yet ***,we found that pER foci are likely phase-separated condensates,the formation of which is mediated by intrinsically disordered region in *** promotes the accumulation of these *** phosphatase 2A,which is known to dephosphorylate pER,hampers the accumulation of the *** the other hand,the circadian kinase DOUBLETIME(DBT)which phosphorylates pER enhances the accumulation of the *** likely facilitates pER foci accumulation by destabilizing the catalytic subunit of protein phosphatase 2A,MICROTUBULE STAR(MTS).In conclusion,here,we demonstrate a key role for phosphorylation in promoting the accumulation of pER foci,while LBR modulates this process by impinging on the circadian phosphatase MTS.

关键词： conclusion separated translational

Enhanced photocatalytic Activity of z-scheme Meso-BiVO_(4)-Au-CdS for Degradation of Rhodamine B

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 869-876页

作者：张雁伟 WANG Yanze li Junguo XIE Jingjing 王文宣 FU zhengyi State Key Laboratory of Advanced Technology for Materials Synthesis and processing Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 441000China

We synthesized BiVO_(4)mesocrystals with ordered assembly structure,and studied the structural order and the relationship between the photodegradation of Rhodamine *** nanoparticles(Nps)were successfully loaded onto Meso-BiVO_(4)by light-assisted induction,and Cd nanoparticles were further selected to be deposited on Au nanoparticles to form z-scheme photocatalyst Meso-BiVO_(4)-Au-CdS *** try and propose to analyze its ordered assembly structure by XRD for the first *** results show that Meso-BiVO_(4)is a mesocrystal with highly exposed(001)plane and directional assembly *** charge separation efficiency of all samples was studied by pL *** results show that the z-scheme Meso-BiVO_(4)-Au-CdS can promote the charge separation and obtain the best carrier separation ***,it has the best photocatalytic activity in the experiment of photocatalytic degradation of rhodamine *** main active species in the degradation process were confirmed by free radical trapping experiment,and the degradation mechanism was put forward.

关键词： biomineralization photosynthesis mesocrystal photocatalysis TiO_(2) BiVO_(4)

Nitrogen mineralization in the oldest climax communities in the eastern Mediterranean region

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2024年第1期35卷 213-228页

作者： Fatma Selcen Sakar Gürcan Güleryüz Department of Biology Section Ecology GörükleGraduate School of Natural and Applied ScienceUniversity of Bursa Uludağ16059 NilüferBursaTurkey Department of Biology Section Ecology GörükleFaculty of Science and ArtsUniversity of Bursa Uludağ16059 NilüferBursaTurkey

In this study,we investigated how tree species affect N mineralization in connection to some soil properties and seconder metabolite levels of litter,in the soil of the old-est native forest *** the oldest pure communi-ties of pinus nigra(pN),Fagus orientalis(FO),and Abies bornmuelleriana(AB)in the mountain range of Mount Uludağ,Bursa,Turkey,annual net yield and N mineraliza-tion in the 0-5-and 5-20-cm soil layers were determined in a field incubation study over 1 *** locations were chosen from 1300 to 1600 m a.s.l.,and moisture content(%),pH,water-holding capacity(%),organic C,total N,and C/N ratio,and annual net mineral N yield of the soil and hydro-lyzed tannic acid and total phenolic compounds in litter were compared for these forest *** had the highest annual net Nmin yield(43.9±4.8 kg ha^(-1) a^(-1)),*** the lowest(30.5±4.2 kg ha^(-1) a^(-1)).Our findings show that in the oldest forest ecosystems,the seasonal soil moisture content and tree species play an essential role in N cycling and that hydrolyzed tannic acids and total phenolic compounds effectively control N *** acid and total phenolics in the litter were found to inhibit nitrification,but total phenolics were found to stimulate ammonification.

关键词： Oldest forest communities Nitrogen mineralization Nitrification Tannic acid Total phenolic litter

Fire resistance evaluation through synthetic fire tests and generative adversarial networks

在线全文

学校读者我要写书评

暂无评论

Frontiers of Structural and Civil Engineering 2024年第4期18卷 587-614页

作者： Aybike Özyüksel Çiftçioğlu M.z.Naser Department of Civil Engineering Manisa Celal Bayar University45140Türkiye School of Civil&Environmental Engineering and Earth Sciences(SCEEES) Clemson UniversityClemsonSC 29631USA Artificial Intelligence Research Institute for Science and Engineering(AIRISE) Clemson UniversityClemsonSC 29631USA

This paper introduces a machine learning approach to address the challenge of limited data resulting from costly and time-consuming fire experiments by enlarging small fire test data sets and predicting the fire resistance of reinforced concrete *** approach begins by creating deep learning models,namely generative adversarial networks and variational autoencoders,to learn the spatial distribution of real fire *** then use these models to generate synthetic tabular samples that closely resemble realistic fire resistance values for reinforced concrete *** generated data are employed to train state-of-the-art machine learning techniques,including Extreme Gradient Boost,light Gradient Boosting Machine,Categorical Boosting Algorithm,Support Vector Regression,Random Forest,Decision Tree,Multiple linear Regression,polynomial Regression,Support Vector Machine,Kernel Support Vector Machine,Naive Bayes,and K-Nearest Neighbors,which can predict the fire resistance of the columns through regression and *** learning analyses achieved highly accurate predictions of fire resistance values,outperforming traditional models that relied solely on limited experimental *** study highlights the potential for using machine learning and deep learning analyses to revolutionize the field of structural engineering by improving the accuracy and efficiency of fire resistance evaluations while reducing the reliance on costly and time-consuming experiments.

关键词： deep learning fire resistance generative adversarial networks machine learning

Dynamics of a rotating ring-stiffened sandwich conical shell with an auxetic honeycomb core

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 963-982页

作者： S.JAHANGIRI A.GHORBANpOUR ARANI z.KHODDAMI MARAGHI Department of Solid Mechanics Faculty of Mechanical EngineeringUniversity of KashanKashan ***Iran Faculty of Engineering Mahallat Institute of Higher EducationMahallat ***Iran

The free vibration analysis of a rotating sandwich conical shell with a reentrant auxetic honeycomb core and homogenous isotropic face layers reinforced with a ring support is *** shell is modeled utilizing the first-order shear deformation theory(FSDT)incorporating the relative,centripetal,and Coriolis accelerations alongside the initial hoop tension created by the *** governing equations,compatibility conditions,and boundary conditions are attained using Hamilton’s *** trigonometric functions,an analytical solution is derived in the circumferential direction,and a numerical one is presented in the meridional direction via the differential quadrature method(DQM).The effects of various factors on the critical rotational speeds and forward and backward frequencies of the shell are *** present work is the first theoretical work regarding the dynamic analysis of a rotating sandwich conical shell with an auxetic honeycomb core strengthened with a ring support.

关键词： free vibration conical shell rotating shell ring support auxetic honeycomb

Orthogonal polynomial expansions for the valuation ofoptions under the stochastic volatility models with stochastic correlation

在线全文

学校读者我要写书评

暂无评论

Journal of Management Science and Engineering 2024年第2期9卷 239-253页

作者： Kevin z.Tong Department of Mathematics and Statistics University of Ottawa585 King EdwardOttawaOntarioK1N 6N5Canada

This work provides a new method for pricing options under the generalized stochastic volatility models with Jacobi stochastic *** method is based on the observation that the generalized models belong to the class of polynomial diffusions and therefore the option prices can be efficiently computed via orthogonal polynomial *** take the Heston and Schöbel-zhu models with stochastic correlation as two specific examples and are able to derive the analytical formulas for the option *** also illustrate the accuracy of the proposed method through a number of numerical experiments.

关键词： Orthogonal polynomial expansions polynomial diffusions Stochastic correlation Jacobi process Stochastic volatility

Controllable CpL response driven by achiral UV-photosensitive dichroic dye through cholesteric liquid crystals

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Chemistry 2024年第4期67卷 1250-1255页

作者： Yihan Chen Yang li Hang li Lulu li Yiwu Quan Yixiang Cheng State Key Laboratory of Analytical Chemistry for life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China Key Laboratory of High-performance polymer Material and Technology of Ministry of Education School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210023China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Versatile stimuli-responsive circularly polarized luminescent(CpL)materials have potential applications in information storage,security encryption,and intelligent *** this study,the z/E isomerization of ultraviolet(UV)-photosensitive achiralα-cyanostilbene derivative was used as an achiral dichroic dye(Switch)to drive the controllable CpL-active response in cholesteric liquid crystals(CLCs).Under irradiation by 365 nm UV light,the resulting CLCs-z-Switch underwent a z-to-E configuration isomerization as CLCs-E-Switch,accompanied by a decrease in its dichroic order parameter(SFvalue)from 0.15to *** the quantum yield(QY)of CLCs-E-Switch increased from 8.1%(CLCs-z-Switch)to 16.8%,the corresponding glumvalues of CpL emission decreased from+0.55/-0.57 to+0.37/-0.39 due to a decrease in the order of helical arrangement of E-Switch in E7 *** study enables photosensitive CLCs-Switch to be applied for optical information storage devices.

关键词： circularly polarized luminescent photosensitive dichroic dye cholesteric liquid crystals chiral induction