检索结果-南通市图书馆

Arctic sea-ice extent: No record minimum in 2023 or recent years

在线全文

学校读者我要写书评

暂无评论

Atmospheric and Oceanic Science Letters 2025年第1期18卷 52-55页

作者： Ola m.Johannessen Tor i.Olaussen Nansen Scientific Society BergenNorway Nansen Environmental and Remote Sensing Center BergenNorway

Arctic sea-ice extent reaches its minimum each year in September. On 11 September 2023 the minimum was 4.969 million square kilometers(***^(2)). This was not a record low, which occurred in 2012, when the minimum was 4.175 ***^(2), 0.794 ***^(2) less than the minimum in 2023. However, the ice extent had decreased by 0.432 ***^(2) compared with 2022. Nevertheless, the summer melting in 2023 was remarkably less than expected when considering the strong heat waves in the atmosphere and ocean, with record temperatures set around the world. in general, there is a high correlation between the long-term decrease in sea-ice extent and the increasing CO_(2) in the atmosphere, where the increase of CO_(2) in recent decades explains about 80% of the decrease in sea ice in September, while the remainder is caused by natural variability.

关键词： Sea ice Arctic minimum ice Climate

The effect of rotation on plane waves in generalized thermo-microstretch elastic solid with one relaxation time for a mode-i crack problem

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2011年第7期20卷 266-278页

作者： Kh.Lotfy mohamed i.A.othman Department of mathematics Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt Department of mathematics Faculty of SciencealmithnabQassim UniversityP.O.Box 6666AlmithnabKingdom of Saudi Arabia

The present paper is aimed at studying the effect of rotation on the general model of the equations of the generalized thermo-microstretch for a homogeneous isotropic elastic half-space solid, whose surface is subjected to a mode-i crack problem. The problem is studied in the context of the generalized thermoelasticity Lord Shulman＇s （L-S） theory with one relaxation time, as well as with the classical dynamical coupled theory （CD）. The normal mode analysis is used to obtain the exact expressions for the displacement components, the force stresses, the temperature, the couple stresses and the microstress distribution. The variations of the considered variables through the horizontal distance are illustrated graphically. Comparisons of the results are made between the two theories with and without the rotation and the microstretch constants.

关键词： Lord-Shulman's theory thermoelasticity microrotation microstretch

Generalized thermoelasticity of the thermal shock problem in an isotropic hollow cylinder and temperature dependent elastic moduli

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2012年第1期21卷 289-294页

作者： ibrahim A.Abbas mohamed i.A.othman Department of mathematics Faculty of Science and Arts-KhulaisKing AbdulAziz UniversityJeddahSaudi Arabia Department of mathematics Faculty of ScienceSohag UniversitySohagEgypt Department of mathematics Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt

in this paper, we construct the equations of generalized thermoelasicity for a non-homogeneous isotropic hollow cylider with a variable modulus of elasticity and thermal conductivity based on the Lord and Shulman theory. The problem has been solved numerically using the finite element method. Numerical results for the displacement, the temperature, the radial stress, and the hoop stress distributions are illustrated graphically. Comparisons are made between the results predicted by the coupled theory and by the theory of generalized thermoelasticity with one relaxation time in the cases of temperature dependent and independent modulus of elasticity.

关键词： generalized thermoelsticity thermal shock temperature dependent elastic moduli finiteelement method

Reflection of PlaneWaves from Electro-magneto-thermoelastic Half-space with a Dual-Phase-Lag model

在线全文

学校读者我要写书评

暂无评论

Computers, materials & Continua 2016年第2期51卷 63-79页

作者： A.m.Abd-Alla mohamed i.A.othman S.m.Abo-Dahab math.Dept. Faculty of ScienceTaif University 888Saudi Arabia Department of mathematics Faculty of ScienceSohag UniversityEgypt math.Dept. Faculty of ScienceZagazig UniversityP.O.Box 44519ZagazigEgypt math.Dept. Faculty of ScienceSouth Valley UniversityQena 83523Egypt

The aim of this paper is to study the reflection of plane harmonic waves from a semi-infinite elastic solid under the effect of magnetic field in a *** expressions for the reflection coefficients,which are the relations of the amplitudes of the reflected waves to the amplitude of the incident waves,are ***,the reflection coefficient ratio variations with the angle of incident under different conditions are shown *** are made with the results predicted by the dual-phase-lag model and Lord-Shulman theory in the presence and absence of magnetic field.

关键词： Reflection Generalized thermoelasticity magnetic field Dual-phaselag model

The gravity impact in a rotating micropolar thermoelastic medium with microtemperatures

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 Ocean Engineering and Science 2018年第4期3卷 325-333页

作者： mohamed i.m.Hilal Ramadan S.Tantawi mohamed i.A.othman Department of mathematics Faculty of ScienceP.O.Box 44519Zagazig UniversityZagazigEgypt Department of Basic Science Faculty of EngineeringSinai UniversityAl-ArishEgypt

A model of micropolar thermoelastic medium with microtemperatures influenced by the gravitational field is *** medium rotates with a uniform angular *** physical quantities are obtained analytically and represented gr... 详细信息

关键词： Gravity micropolar thermoelasticity microtemperatures Rotation

The effect of gravity and inclined load in micropolar thermoelastic medium possessing cubic symmetry under G-N theory

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 Ocean Engineering and Science 2018年第4期3卷 288-294页

作者： mohamed i.A.othman S.m.Abo-Dahab Haneen A.Alosaimi Department of mathematics Faculty of ScienceZagazig UniversityZagazig 44519Egypt Department of mathematics Faculty of ScienceTaif UniversityTaif 888Saudi Arabia Department of mathematics Faculty of ScienceSouth Valley UniversityQena 83523Egypt

The problem of the micropolar thermoelastic medium under(G-N)theory of both types ii,iii under the effect of the gravity was *** normal mode analysis is used to obtain the solution of the physical *** are made between the results predicted by the(G-N)theory of type ii and type iii in the presence and absence of gravity and for different values of the angle of inclination.©2018 Shanghai Jiaotong *** by Elsevier B.V.

关键词： micropolar thermoelasticity Green-Naghdi theory Normal mode method Gravity inclined load.

Assessing the visualization of space and traffic volume using GiS-based processing and visibility parameters of space syntax

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Geo-Spatial information Science 2020年第3期23卷 209-221,I0002页

作者： Fazzami othman Zaharah m.Yusoff Siti Aekbal Salleh Centre of Studies for Surveying Sciences and Geomatics Faculty of ArchitecturePlanning and SurveyingUniversiti Teknologi MARAShah AlamSelangorMalaysia

Streets and physical layouts can be inherent in a sustainable city by emphasizing the use of space with planned strategies by promoting the movement of people and social behaviors for enhancing an economic *** analysis of the space layout is beneficial for defining the urban areas that can affect street behavior.A GiS incorporated with a space syntax can help to propagate the effectiveness of a spatial analysis in a study on urban *** integration of the computational pieces of both a GiS analytical tool and space syntax parameters will stimulate research oriented urban systems and spatial morphologies combined with a spatial ***,the development of livability can be affected by a set of parameters that define the used ***,this paper was aimed at examining the space syntax parameters for space visualization to evaluate street behavior using the GiS processing and space syntax *** this study,a spatial analysis was used to generate spatial information on traffic volume,while a space syntax was used to test the street ***,a predictive analysis was conducted to identify the correlation between traffic behavior and a set of *** results showed that integration and direct visibility were significant to the traffic *** of the streets that were linked to the commercial area showed high integration and direct visibility,which increased by more than half,compared with the unlinked *** on the statistical analysis,both parameters recorded aprobability of less than 5%.The results showed that any space designed with a continuous,direct and clear traffic volume will lead to increased integration and direct visibility,thus influencing a natural vehicle movement.

关键词： Space behavior traffic volume space syntax isovist visibility analysis

Study of micro-elongated thermoelastic medium loaded with a piezoelectric layer under the influence of gravity using the dual-phase-lag model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

international Journal of mechanical System Dynamics 2023年第2期3卷 136-145页

作者： mohamed i.A.othman Ebtesam E.m.Eraki mohamed F.ismail Department of mathematics Faculty of ScienceZagazig UniversityZagazigEgypt Department of Engineering mathematics and Physics Higher Institute of EngineeringShorouk AcademyAl-Shorouk CityEgypt

This paper aims to examine the influence of gravity on a thermoelastic microelongated layer when a piezoelectric layer is above it,utilizing the theory of Lord–Shulman(L–S)and also the model of dual‐phase‐lag(DPL).A partial differential equation was transformed into an ordinary differential equation using the normal mode *** epoxy numerical computations are carried out,and the results are presented in graphical *** L–S theory and the model of DPL are compared in the presence and absence of gravity and it is found that gravity has quite a massive influence on all the physical quantities.

关键词： piezoelectrics normal mode analysis gravity micro‐elongated thermoelastic DPL model

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer m.Colón-mercado Aranza i.Torrado-Tapias iris K.Salgado Jose m.Santiago Samuel E.Ocasio Rivera Dina P.Bracho-Rincon Luis H.Pagan Rivera Jorge D.miranda Department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA institute of Neurobiology San JuanPRUSA

in addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma