检索结果-南通市图书馆

Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 139-156页

作者： h.hOSSEINI O.BALILAShAKI Department of Mechanical Engineering Faculty of EngineeringGolestan University

The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically. It is assumed that the source is located outside the cavity at a specified distance from the borehole axis. The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed. Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid, empty borehole, and rigid inclusion with a hard boundary is employed for the analysis. Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions, the proposed boundary conditions at the interface are satisfied. Stresses are formulated by means of wave potential functions in a three-dimensional(3D) manner. The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra. Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis. To give an overall outline of the study, a numerical example is presented. The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values. In addition, the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole. Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases, and good agreement is achieved.

关键词：

Neuroinflammation as a therapeutic target in huntington's disease

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第3期20卷 817-818页

作者： Andrea Kwakowsky Thulani h.Palpagama Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CentreUniversity of GalwayGalwayIreland

In 1872, George huntington presented his essay “On Chorea” to the Meigs and Mason Academy of Medicine and, in doing so, detailed a disease that would later bear his name. huntington's disease(hD) is a genetic, neurodegenerative disease that manifests as the loss of motor control,cognitive impairment,and mood and psychiatric changes in paents.

关键词： huntington inflammation Medicine

Glial response in the midcingulate cortex in huntington’s disease

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第1期20卷 207-208页

作者： Thulani h.Palpagama Andrea Kwakowsky Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CenterUniversity of GalwayGalwayIreland

huntington’s disease(hD)is a genetic disease characterized by the progressive degeneration of the striatum and *** can present with a variety of symptoms that can broadly be classified into motor symptoms,inclusive of choreatic movements and rigidity,mood and psychiatric symptoms,such as depression and apathy,and cognitive symptoms,such as cognitive *** causal mutation underlying hD results from an expansion of a CAG repeat sequence on the IT15 gene,resulting in the formation and accumulation of a mutant huntingtin protein.

关键词： huntington degeneration cortex

Does mesenchymal stem cell’s secretome affect spinal sensory circuits?Implication for pain therapies

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第1期20卷 181-183页

作者： Francesco Ferrini Esri h.Juárez Adalberto Merighi Department of Veterinary Sciences University of TurinGrugliascoTOItaly Department of Psychiatry and Neuroscience UniversitéLavalQuébec CityQCCanada

Mesenchymal stem cells(MSCs)are multipotent adult stem cells of mesodermal origin that can be isolated from various tissues,including bone marrow,tooth pulp,adipose tissue,and umbilical *** have gained significant attention in regenerative medicine due to their ability to modulate the immune system and favor tissue *** enrich the medium in which they are cultivated with a broad range of bioactive molecules,including growth factors,cytokines,chemokines,enzymes,nucleic acids,and extracellular vesicles that collectively compose the MSC *** increasing number of pre-clinical studies suggest that delivering in vivo an MSC-conditioned medium(i.e.,the medium collected from MSC cultures after at least 3 days of exposure)exerts neuroprotective and anti-inflammatory effects in a variety of neurological conditions.

关键词： protective clinical collective

Target-Oriented Inversion of Time-Lapse Seismic Waveform Data

在线全文

学校读者我要写书评

暂无评论

Communications in Computational Physics 2020年第6期28卷 249-275页

作者： Xingguo huang Morten Jakobsen Kjersti solberg Eikrem Geir Nævdal Department of Earth Science University of BergenP.O.Box 78035020 BergenNorway NORCE Norwegian Research Centre Postboks 225838 BergenNorway

Full waveform inversion of time-lapse seismic data can be used as a means of estimating the reservoir changes due to the *** the repeated computa-tions for the monitor surveys lead to a large computational cost,time-lapse full wave-form inversion is still considered to be a challenging *** address this problem,we present an efficient target-oriented inversion scheme for time-lapse seismic data using an integral equation formulation with Gaussian beam based Green’s function *** proposed time-lapse approach allows one to perform a local inversion within a small region of interest(e.g.a reservoir under production)for the monitor *** have verified that the T-matrix approach is indeed naturally target-oriented,which was mentioned by Jakobsen and Ursin[24]and allows one to reduce the compu-tational cost of time-lapse inversion by focusing the inversion on the target-area *** method is based on a new version of the distorted Born iterative T-matrix inverse scattering *** Gaussian beam and T-matrix are used in this approach to perform the wavefield computation for the time-lapse inversion in the baseline model from the survey surface to the target *** have provided target-oriented inversion results of the synthetic time-lapse waveform data,which shows that the proposed scheme reduces the computational cost significantly.

关键词： Waveform inversion time-lapse seismic seismic inverse scattering target-oriented inversion Gaussian beam based Green’s function

Effect of nanoparticle(Pd, Pd/Pt, Ni) deposition on high temperature hydrogenation of Ti-V alloys in gaseous flow containing CO

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

Progress in Natural Science:Materials International 2017年第1期27卷 93-98页

作者： S.Suwarno M.Williams J.K.solberg V.A.Yartys Department of Mechanical Engineering Institut Teknologi Sepuluh Nopember Department of Materials Science and Engineering NTNU Institute for Energy Technology University of the Western Cape

The hydrogenation properties of Ti-V hydrides coated with nanoparticles have been studied in gaseous mixtures of argon and hydrogen with and without additions of 1% CO. Nanoparticles of Pd, Ni, and co-deposited Pd/Pt with particle sizes of;0–60 nm were formed by electroless deposition on the hydride surfaces. The alloy resistance to CO could be significantly improved by particle deposition. Large amounts of hydrogen were absorbed in a CO-containing gas when Ni and Pd/Pt deposition had been applied, while pure Pd deposition had no positive effect. Ni was found to have a stronger effect than those of Pd/Pt and Pd, possibly because of the size effect of Ni nanoparticles.

关键词： Metal hydride Titanium Vanadium Nanoparticle Palladium Nickel Platinum Carbon monoxide

Comparative chemical sensor for detection of chromium(Ⅵ) in aqueous solution

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Optoelectronics Letters 2025年第1期21卷 21-27页

作者： Sura h.AL-REKABI A.A.ALWAhIB Electrical Technique Department Al Suwayrah Technical Institute Middle Technical University Laser and Optoelectronics Department University of Technology-Iraq

A process for purifying aqueous solutions containing heavy and toxic metals such as chromium（Cr） has been investigated. One of the extremely harmful pollutants in rivers and seawater is the heavy metal ions due to their direct impacts on human, animals and plants are hexavalent Cr（Ⅵ）. Consequently, highly sensitive sensor to detect Cr is essential. Surface plasmon resonance（SPR） technique has attracted huge research interest in detecting heavy metals specifically. In this study, three types of prism-based SPR sensor, gold（Au）/silver（Ag）, Au/polyaniline（PANI） and Au/titanium dioxide（TiO2） nanostructured films, are investigated as potential sensing material to detect the presence of Cr（Ⅵ） ions in water. The base Au layer with thickness of 48.3 nm is deposited on a glass slide for all sensors. For Au/Ag, Au/PANI nanofibers and Au/TiO2sensor films, the Cr（Ⅵ） concentration is varied from 1 ppm to 15 ppm with sensitivity of 0.270 °ppm-1, 0.082 °ppm-1and 0.039 °ppm-1, respectively. Based on these results, the Au/PANI nanofibers are the most sensitive to Cr（Ⅵ） among the tested sensing materials.

关键词： Titanium dioxide

Free vibration and transient response of double curved beams connected by intermediate straight beams

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-TALOOKOLAEI h.GhANDVAR E.JUMAEV S.KhATIR T.CUONG-LE School of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and Science Center for Engineering Application and Technology Solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. The strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. Subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

关键词：

Formation of precipitates and recrystallization resistance in Al-Sc-Zr alloys

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2012年第8期22卷 1866-1871页

作者：贾志宏 Jostein RφYSET Jan Ketil solberg 刘庆重庆大学材料科学与工程学院重庆400044 Department of Materials Science and Engineering Norwegian University of Science and TechnologyNO-7491TrondheimNorway hydro Aluminium Research and Technology Development NO-6600SunndalsφraNorway

Al-x%Sc-0.11%Zr alloys （x=0, 0.02, 0.05, 0.08, 0.11, 0.15） were produced by a chill cast procedure. The effect of Sc content on the precipitation of Al3（Sc,Zr） during heat treatment at 475 °C for 12 h was studied. Nucleation, precipitation and distribution of Al3（Sc,Zr） precipitates were found to be strongly related to the Sc content. With increasing the Sc content, the average radius of the precipitates decreases, while the number density of the precipitates increases, as investigated by transmission electron microscopy （TEM）. The distribution of the precipitates becomes more and more homogeneous when the Sc content is increased. The recrystallization resistance of samples that was 90% cold rolled and isothermal annealed for half an hour in the temperature range of 200-600 °C was investigated. The results show that the recrystallization temperature varies from 250 °C for the alloy without Sc to about 600 °C for the alloy containing 0.15% Sc because of the high density of Al3（Sc,Zr） precipitates.

关键词： aluminium alloy precipitate recrystallization resistance