检索结果-南通市图书馆

Fatigue Failure of notched Specimen—A Strain-Life Approach

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Materials Sciences and Applications 2011年第12期2卷 1730-1740页

作者： Bikash Joadder Jagabandhu Shit Sanjib Acharyya sankar Dhar 不详

Failure cycles of notched round specimens under strain controlled cyclic loading are predicted using strain—life relations obtained from experiment for plain fatigue round specimens. For notched specimens, maximum strain occurs at notch root and is different from applied controlled strain. The maximum strain is computed by appropriate Finite element analysis using the FE software ABAQUS. FE model and material parameters are validated by comparing the FE results and experimental results of LCF tests of round specimens. This value of maximum strain is used for prediction of failure cycles. Prediction is compared with the experimental results. The results show good matching.

关键词： Strain Life Equation Failure Cycle notched Specimen LCF Cyclic Plasticity

Effect of Cooling Conditions on Mechanical and Microstructural Behaviours of Friction Stir Processed AZ31B Mg Alloy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Modern Mechanical Engineering 2017年第4期7卷 144-160页

作者： sankar Ramaiyan Rathinasuriyan Chandran Senthil Kumar Velukkudi Santhanam Department of Mechanical Engineering Anna University Chennai India

Friction stir processing (FSP) is an important microstructural alteration process used recently in the engineering field. Grains alteration and hence the mechanical properties of the possessed zone are controlled by the temperature, heating and cooling rate. In this work, AZ31B magnesium samples were friction stir processed in three different cooling conditions like air, water and cryogenic (liquid nitrogen) cooling. 1000 rpm and 60 mm/min were kept constant as tool rotation speed and traverse speed respectively in all the three mediums. The consequence of these conditions on thermal fields, axial force, resulting grain structure and mechanical properties?was?studied. It is found that the cryogenic treated friction stir processed samples exhibit fine grain structures and hence offer better mechanical properties than the air and water cooled processed samples.

关键词： Friction Stir Processing AZ31B Magnesium Alloy Cryogenic Coolant Liquid nitrogen and Mechanical Properties Axial Force Submerged Friction Stir Processing

Fabrication and Characterization of Graphene Based nanocomposite for Electrical Properties

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Materials Physics and Chemistry 2015年第1期5卷 22-30页

作者： Manoj Kumar Pati Puspalata Pattojoshi Gouri sankar Roy Department of Physics KIIT University Odisha India Department of Physics College of Engineering and Technology Bhubaneswar Odisha India

In the present study, we have described the synthesis of acid functionalized graphene (GE) which was grafted to chitosan (CH) by first reacting the oxidized GE with thionyl chloride to form acyl-chlorinated GE. This product was subsequently dispersed in chitosan and covalently grafted to form GE-chitosan. GE-chitosan was further grafted onto poly(anthranilic acid) (PAA) by free radical polymerization conditions, to yield GE-g-chitosan-g-PAA for our investigations. The structure of GE-CH-PAA composites was characterized by X-ray diffraction (XRD) pattern, Fourier transform infrared (FTIR) spectroscopy, thermo gravimetric analysis (TGA), cyclovoltammetrie (CV) and transmission electron microscopy (TEM). XRD report suggested the strongly crystalline character of the specimen prepared. The performance of cycle voltammeter was attributed to the GE-CH-PAA, which provided a large number of active sites and good electrical conductivity. Experimental results suggested that nanocomposites could be combined together for industrial applications.

关键词： Graphene Chitosan Poly(Anthranilic Acid) Electrical Conductivity

Assessment of School Infrastructure at Primary and Upper Primary Level: A Geospatial Analysis

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 Geographic Information System 2012年第5期4卷 412-424页

作者： Gouri sankar Bhunia Pravat Kumar Shit Soumen Dubai Department of Geography & Environment Management Vidyasagar University Medinipur India Office of the Sarva-Siksha-Mission (SSM) Paschim Medinipur India Rajendra Memorial Research Institutes of Medical Sciences (ICMR) Bihar India

With the introduction of powerful and high-speed personal computers, proficient techniques for infrastructure development and management have advanced, of which Geoinformatics technology is of great significance. An attempt has been made for broad mapping and analysis of existing infrastructures in the context of planning scheme in Paschim Medinipur district, and to delineate the development zones of educational infrastructure facilities. The thematic layers considered in this study are infrastructure accessibility, type and condition of classroom and number of classroom allocated for the educational system at primary and upper primary level. Moran’s I statistics was used to estimate the spatial distribution of elementary infrastructure across the district. All these themes and their individual features were then assigned weights according to their relative importance in educational development and corresponding normalized weights were obtained based on the Saaty’s analytical hierarchy process. The thematic layers were finally integrated in GIS software based on multi-criteria approach to yield educational development infrastructure index. Moran’s I statistics shows girl’s toilet, electric and boundary wall facility within the district are clustered in pattern at primary level. At the upper primary level, only electric and computer facilities shows the clustered distribution across the district. However, four different zones have been delineated, namely ‘very good’, ‘good’, ‘moderate’ and ‘poor’. The block covered by very good elementary educational infrastructure facility is Daspur –I and Dantan –II at primary level and Keshiary block at upper primary level in Paschim Medinipur district. Finally, it is concluded that the Geoinformatics technology is very efficient and useful for the identification of infrastructure development.

关键词： Educational Infrastructure Spatial Auto-Correlation Saaty’s Analytical Hierarchy Process Multi-Criteria Approach

Combined Effects of Hall Current and Radiation on MHD Free Convective Flow in a Vertical Channel with an Oscillatory Wall Temperature

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Fluid Dynamics 2013年第1期3卷 9-22页

作者： sankar Kumar Guchhait Sanatan Das Rabindra nath Jana Department of Applied Mathematics Vidyasagar University Midnapore India Department of Mathematics University of Gour Banga English Bazar India

The combined effects of Hall current and radiation on an unsteady MHD free convective flow of a viscous incompressible electrically conducting fluid in a vertical channel with an oscillatory wall temperature have been studied. We have considered two different cases 1) flow due to the impulsive motion of one of the channel walls and 2) flow due to the accelerated motion of one of the channel walls. The governing equations are solved analytically using the Laplace transform technique. It is found that the primary velocity and the magnitude of the secondary velocity increase with an increase in Hall parameter for both the impulsive as well as the accelerated motions of one of the channel walls. An increase in either radiation parameter or frequency parameter leads to decrease in the primary velocity and the magnitude of the secondary velocity for both the impulsive as well as accelerated motions of one of the channel walls. The fluid temperature decreases with an increase in radiation parameter. Further, the shear stresses at the left wall reduce with an increase in either radiation parameter or frequency parameter for both the impulsive as well as the accelerated motions of one of the channel wall.

关键词： Hall Current MHD Free Convection Radiation Prandtl number Grashof number Frequency Parameter Impulsive Motion Accelerated Motion

Assessment of Factors Affecting Ephemeral Gully Development in Badland Topography: A Case Study at Garbheta Badland (Pashchim Medinipur,

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 Geosciences 2013年第2期4卷 461-470页

作者： Pravat Kumar Shit Gouri sankar Bhunia Ramkrishna Maiti Department of Geography & Environment Management Vidyasagar University Medinipur India Rajendra Memorial Research Institutes of Medical Sciences (ICMR) Patna Bihar India

Gully erosion in the Paschim Medinipur district of West Bengal, Indiahas been an issue of anxiety, formed by the amputation of soil from narrow channels through the accretion of surface runoff. Here, we attempted to investigate the erosion variability of gully in a micro catchment area, and also scrutinized the gully cross-sectional areas as distinct components of gully volumes. Twelve gullies were randomly selected in different slopes. To determine the geometric growth of the gully dimensions and soil loss, the initial length of gully, the width of the gully and depth of respective gullies was monitored in different seasons. Univariate analysis was conducted to measure the association between gully head retreat and vegetation coverage, slope, rainfall volume and runoff contributing area. We found strong and significant relation between the slope of gully head and linear retreat in the pre monsoon (p 0.008) and post monsoon (p 0.024) season respectively. Conversely, rainfall volume and gully head retreat showed a strong relationship in the pre monsoon (r = 0.80), monsoon (r = 0.66) and post-monsoon period (r = 0.94);while meager relationship was observed with rainfall intensity (r = 0.06). Results also illustrated that the overall retreat of gully head had very strong and positive relationship with the runoff contributing area (r = 0.89, p 0.001), and maximum gully erosion was observed in the monsoon period (55.67%). These results indicate that slope, rainfall and runoff contributing area have a strong positive influence on gully erosion in Paschim Medinipur district, since the initiation of the gully.

关键词： Gully Erosion Gully Heads Rainfall Runoff Contributing Area Sediment Yield

Developments of Rill networks: An Experimental Plot Scale Study

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 Water Resource and Protection 2013年第2期5卷 133-141页

作者： Pravat Kumar Shit Gouri sankar Bhunia Ramkrishna Maiti Department of Geography & Environment Management Vidyasagar University Medinipur India Senior Research Fellow (ICMR) Rajendra Memorial Research Institutes of Medical Sciences (ICMR) Bihar India

Enumerating the relative proportions of soil losses due to rill erosion processes during monsoon and post-monsoon season is a significant factor in predicting total soil losses and sediment transport and deposition. Present study evaluated the rill network with simulated experiment of treatments on varying slope and rainfall intensity to find out the rill erosion processes and sediment discharge in relation to slope and rainfall intensity. Results showed a significant relationship between the rainfall intensity and sediment yield (r = 0.75). Our results illustrated that due to increase in rainfall intensity represent the development of efficient rill network while, no rill was found with a slope of 20° and a rainfall intensity of 60 mm·h-1. The highest rill length was observed in plot E with 20° slope and 120 mm·h-1 rainfall intensity at 360 minutes. Positive and strong correlation (R2 = 0.734, P 0.001) was observed between the cumulative rainfall intensity and sediment discharge. A longitudinal profile was delineated and showed that the depth and numbers of depressions amplified with time and were more prominent for escalating rainfall intensity for its steeper slopes. Information derived from the study could be applied to estimate longer-term erosion stirring over larger areas possessing parallel landforms.

关键词： Rill network Slope Gradient Rainfall Simulation Sediment Yield

CsPbBr3 perovskite quantum-dot paper exhibiting a highest 3 dB bandwidth and realizing a flexible white-light system for visible-light communication

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Photonics Research 2021年第12期9卷 2341-2350页

作者： KOnTHOUJAM JAMES SInGH XIAOTOnG FAn AnnADA sankar SADHU CHUn-HO LIn FAnG-JYUn LIOU TInGZHU WU YU-JUnG LU JR-HAU HE ZHOnG CHEn TOM WU HAO-CHUnG KUO Department of Photonics&Institute of Electro-Optical Engineering College of Electrical and Computer EngineeringNational Yang Ming Chiao Tung UniversityHsinchu 30010Taiwan International Ph.D.Program in Photonics(UST) College of Electrical and Computer EngineeringNational Yang Ming Chiao Tung UniversityHsinchu 30010Taiwan Department of Electronic Science Fujian Engineering Research Center for Solid-State LightingXiamen UniversityXiamen 361005China School of Materials Science and Engineering University of New South WalesSydneyNSW 2052Australia Research Center for Applied Sciences Academia SinicaTaipei 11529Taiwan Department of Materials Science and Engineering City University of Hong KongKowloon TongHong KongChina

We propose a flexible white-light system for high-speed visible-light communication(VLC)applications,which consists of a semipolar blue InGan/Gan single-quantum-well micro-light-emitting diode(LED)on a flexible substrate pumping green CsPbBr3 perovskite quantum-dot(PQD)paper in nanostructure form and red CdSe QD *** highest bandwidth for CsPbBr3 PQD paper,229 MHz,is achieved with a blue micro-LED pumping source and a high data transmission rate of 400 Mbps;this is very promising for VLC *** 817 MHz maximum bandwidth and a 1.5 Gbps transmission speed are attained by the proposed semipolar blue *** proposed flexible white light system and the high-bandwidth PQD paper could pave the way for VLC wearable devices.

关键词： pumping communication quantum

Optomechanical Gyroscope

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Optomechanical Gyroscope