检索结果-南通市图书馆

response of photonic Hydrogels of Homogeneous particles to Uranyl Ions in Aqueous Solutions

在线全文

学校读者我要写书评

暂无评论

photonic Sensors 2023年第4期13卷 50-61页

作者： r.G.JOSHI Deepak K.GUpTA p.AMESH p.K.pArIDA T.r.rAVINDrAN Materials Science Group Indira Gandhi Centre for Atomic ResearchA CI of Homi Bhabha National InstituteKalpakkam 603102India Materials Chemistry and Metal Fuel Cycle Group Indira Gandhi Centre for Atomic ResearchA CI of Homi Bhabha National InstituteKalpakkam 603102India Metallurgy and Materials Group Indira Gandhi Centre for Atomic ResearchA CI of Homi Bhabha National Institute(HBNI)Kalpakkam 603102India

We study here the response of photonic hydrogels(pHs),made of photonic crystals of homogeneous silica particles in polyacrylamide hydrogels(SpHs),to the uranyl ions 22 UO_(2)^(2+) in aqueous *** is found that the reflection spectra of the SpH show a peak due to the Bragg diffraction,which exhibits a blue shift in the presence of 22 UO_(2)^(2+).Upon exposure to the SpH,22 UO_(2)^(2+)gets adsorbed on the SpH and forms complex coordinate bonds with multiple ligands on the SpH,which causes shrinking of hydrogel and leads to the blue shift in the diffraction *** amount of the blue shift in the diffraction peak increases monotonically up to 22 UO_(2)^(2+)concentrations as high as 2300μ*** equilibration time for the shift in the Bragg peak upon exposure to 22 UO_(2)^(2+)is found to be~30 *** results are in contrast to the earlier reports on photonic hydrogels of inhomogeneous microgel particles hydrogel(MpH),which shows the threshold 22 UO_(2)^(2+)concentration of~600μM,below which the diffraction peak exhibits a blue shift and a change to a red shift above *** equilibration time for MpH is~300 *** observed monotonic blue shift and the faster time response of the SpH to 22 UO_(2)^(2+)as compared to the MpH are explained in terms of homogeneous nature of silica particles in the SpH,against the porous and polymeric nature of microgels in the *** also study the extraction of 22 UO_(2)^(2+)from aqueous solutions using the *** extraction capacity estimated by the arsenazo-III analysis is found to be 112 mM/kg.

关键词： photonic hydrogels uranium extraction and monitoring arsenazo-Ⅲ-uranium complex polyacrylamide hydrogel UV-visible spectroscopy

Fracture Toughness and Microcracks on Natural Apophyllite 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

Journal of Materials Science & Technology 1998年第2期14卷 156-160页

作者： Dhar, p.r. Bamzai, K. Kotru, p.N. Dept. of physics University of Jammu Jammu-180004 India

results on fracture toughness of natural apophyllite crystals when they were subjected to impact were presented. The morphology of the cracks and fracture has been studied. It was found that the crack formation does not show any anisotropic property and remains the same whatever may be the orientation of the crystal. The average values of the fracture toughness K//c and brittleness index, as determined from measurements of crack length, were estimated to be 0.107 g mu m** minus **3**/**2 and 4.19 mu m** minus **1**/**2 respectively for the a(100) plane. The yield strength for a(100), p(111) and C(001) planes of apophyllite crystals for lower loads is 2250, 2160 and 1840 Mpa and for higher loads is 1510, 1600 and 1430 Mpa respectively. (Edited author abstract) 7 refs.

关键词： Crystals

reliable energy-efficient routing with novel route update in wireless sensor networks

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied physics & Engineering) 2008年第8期9卷 1099-1110页

作者： r. VIDHYAprIYA p. T. VANATHI Department of Information Technology PSG College of TechnologyCoimbatore 641004 India Department of Electronics and Communication Engineering PSG College of TechnologyCoimbatore 641004 India

In this paper we introduce a novel energy-aware routing protocol rEpU (reliable, efficient with path update), which provides reliability and energy efficiency in data delivery. rEpU utilizes the residual energy available in the nodes and the re-ceived signal strength of the nodes to identify the best possible route to the destination. reliability is achieved by selecting a number of intermediate nodes as waypoints and the route is divided into smaller segments by the waypoints. One distinct ad-vantage of this model is that when a node on the route moves out or fails, instead of discarding the whole original route, only the two waypoint nodes of the broken segment are used to find a new path. rEpU outperforms traditional schemes by establishing an energy-efficient path and also takes care of efficient route maintenance. Simulation results show that this routing scheme achieves much higher performance than the classical routing protocols, even in the presence of high node density, and overcomes simul-taneous packet forwarding.

关键词： Wireless sensor networks (WSNs) routing Energy efficiency received signal strength indicator (rSSI) route repair Waypoint

Behavior of an indigenously fabricated transferred arc plasma furnace for smelting studies

在线全文

学校读者我要写书评

暂无评论

plasma Science and Technology 2018年第3期20卷 136-145页

作者： A K MANDAL r K DISHWAr O p SINHA Department of Metallurgical Engineering IIT(BHU)

The utilization of industrial solid waste for metal recovery requires high-temperature tools due to the presence of silica and alumina, which is reducible at high temperature. In a plasma arc furnace, transferred arc plasma furnace（TAp） can meet all requirements, but the disadvantage of this technology is the high cost. For performing experiments in the laboratory, the TAp was fabricated indigenously in a laboratory based on the different inputs provided in the literature for the furnace design and fabrication. The observed parameters such as arc length, energy consumption, graphite electrode consumption, noise level as well as lining erosion were characterized for this fabricated furnace. The nitrogen plasma increased by around 200 K（200 ℃） melt temperature and noise levels decreased by ~10 d B compared to a normal *** plasma offered 100 K（100 ℃） higher melt temperature with ~5 d B higher sound level than nitrogen plasma. Nitrogen plasma arc melting showed lower electrode and energy consumption than normal arc melting, whereas hydrogen plasma showed lower energy consumption and higher electrode consumption in comparison to nitrogen plasma. The higher plasma arc temperature resulted in a shorter meltdown time than normal arc with smoother arcing. Hydrogen plasma permitted more heats, reduced meltdown time, and lower energy consumption, but with increased graphite consumption and crucible wear. The present study showed that the fabricated arc plasma is better than the normal arc furnace with respect to temperature generation, energy consumption, and environmental friendliness. Therefore, it could be used effectively for smelting-reduction studies.

关键词： smelting transferred arc plasma furnace characterization hydrogen and nitrogen plasma hollow electrode graphite and magnesite lining

Scaling laws for gas-solid riser flow through two-fluid model simulation

在线全文

学校读者我要写书评

暂无评论

particuology 2011年第2期9卷 121-129页

作者： p.r.Naren Vivek.V.ranade CrEST National Chemical Laboratory Chemical Engineering Department Institute of Chemical Technology

Scale up of gas-solid circulating fluidized bed （CFB） risers poses many challenges to researchers. In this paper, CFD investigation of hydrodynamic scaling laws for gas-solid riser flow was attempted on the basis of two-fluid model simulations, in particular, the recently developed empirical scaling law of Qi, Zhu, and Huang （2008）. A 3D computational model with periodic boundaries was used to perform numerical experiments and to study the effect of various system and operating parameters in hydrodynamic scaling of riser flow. The Qi scaling ratio was found to ensure similarity in global parameters like overall cross- sectional average solid holdup or pressure drop gradient. However, similarity in local flow profiles was not observed for all the test cases. The present work also highlighted the significance of error bars in reporting experimental values.

关键词： risersScalingCFDperiodic boundaryTwo-fluid modelError bar

Si/Si C-based DD hetero-structure IMpATTs as MM-wave power-source:a generalized large-signal analysis

在线全文

学校读者我要写书评

暂无评论

Journal of Semiconductors 2015年第6期36卷 58-63页

作者： Moumita Mukherjee p.r.Tripathy S.p.pati Centre for MM-wave Semiconductor Devices and Systems (CMSDS) DRDO Hi-Tech College of Engineering Former professor of Sambalpur University

A full-scale, self-consistent, non-linear, large-signal model of double-drift hetero-structure IMpATT diode with general doping profile is derived. This newly developed model, for the first time, has been used to analyze the large-signal characteristics of hexagonal SiC-based double-drift IMpATT diode. Considering the fabrication feasibility, the authors have studied the large-signal characteristics of Si/SiC-based hetero-structure devices. Under small-voltage modulation （~ 2%, i.e. small-signal conditions） results are in good agreement with calculations done using a linearised small-signal model. The large-signal values of the diode＇s negative conductance （5 × 106 S/m2）, susceptance （10.4 × 107 S/m2）, average breakdown voltage （207.6 V）, and power generating efficiency （15%, rF power： 25.0 W at 94 GHz） are obtained as a function of oscillation amplitude （50% of DC breakdown voltage） for a fixed average current density. The large-signal calculations exhibit power and efficiency saturation for large-signal （〉 50%） voltage modulation and thereafter decrease gradually with further increasing voltage-modulation. This generalized large-signal formulation is applicable for all types of IMpATT structures with distributed and narrow avalanche zones. The simulator is made more realistic by incorporating the space-charge effects, realistic field and temperature dependent material parameters in Si and SiC. The electric field snap-shots and the large-signal impedance and admittance of the diode with current excitation are expressed in closed loop form. This study will act as a guide for researchers to fabricate a high-power Si/SiC-based IMpATT for possible application in high-power MM-wave communication systems.

关键词： Si/SiC hetero-structure double drift diode full-scale large-signal modelling high-power parasiticeffects noise-analysis

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2010年第12期31卷 1517-1526页

作者： p.LOGANATHAN p.pUVI-ArASU r.KANDASAMY Department of Mathematics Anna University Erode Sengunthar Engineering College Computational Fluid Dynamics FSSWUniversiti Tun Hussein Onn Malaysia

Combined heat and mass transfer on free, forced, and mixed convection flow along a porous wedge with magnetic effect in the presence of chemical reaction is investigated. The flow field characteristics are analyzed by the runge-Kutta-Gill scheme with the shooting method as well as the local non-similarity method up to the third level of truncation, which are used to reduce the governing partial differential equations into nine ordinary differential equations. The governing boundary layer equations are converted to a dimensionless form by Falkner-Skan transformations. Because of the effect of suction/injection on the wall of the wedge with buoyancy force and variable wall temperature, the flow field is locally non-similar. Numerical calculations up to the third order level of truncation are carried out as a special case for different values of dimensionless parameters. Effects of the magnetic field strength in the presence of chemical reaction with variable wall temperature and concentration on the dimensionless velocity, temperature and concentration profiles are shown graphically.

关键词： local non-similarity suction/injection buoyancy force magnetic field wallof wedge

Viscous and Ohmic heating effects in doubly stratified free convective flow over vertical plate with radiation and chemical reaction

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2013年第2期34卷 139-152页

作者： p.GANESAN r.K.SUGANTHI p.LOGANATHAN Department of Mathematics Anna University Chennai

An analysis is carried out to study the combined effects of viscous and Ohmic heating in the transient, free convective flow of a viscous, incompressible, and doubly stratified fluid past an isothermal vertical plate with radiation and chemical reactions. The governing boundary layer equations are solved numerically by an implicit finite difference scheme of the Crank-Nicolson type. The influence of different parameters on the velocity, the temperature, the concentration, the skin friction, the Nusselt number, and the Sherwood number is discussed with graphical illustrations. It is observed that an increase in either the thermal stratification or the mass stratification parameter decreases the velocity. An increase in the thermal stratification increases the concentration and decreases the temperature while an opposite effect is observed for an increase in the mass stratification. An augmentation in viscous and Ohmic heating increases the velocity and temperature while decreases the concentration. The results are found to be in good agreement with the existing solutions in literature.

关键词： thermal stratification mass stratification Ohmic dissipation viscousdissipation chemical reaction radiation

在线全文

学校读者我要写书评

暂无评论

经验的认知私人性

世界哲学 2025年第02期 126-139页

作者： p.M.S.哈克张学广徐皓乙西北大学哲学学院外国哲学研究中心

经验的认知私人性学说认为，只有我真的知道我拥有一种既定的经验，其他人最多只能猜测，但无法真的知道我拥有的经验，或者不能像我一样确定地知道这一点。这一学说是笛卡尔和英国古典经验主义以来占主导地位的心灵理论，并为当代神经... 详细信息

经验的认知私人性学说认为，只有我真的知道我拥有一种既定的经验，其他人最多只能猜测，但无法真的知道我拥有的经验，或者不能像我一样确定地知道这一点。这一学说是笛卡尔和英国古典经验主义以来占主导地位的心灵理论，并为当代神经科学和心理学所加持。但是，该学说建立在对“内省”“意识”“察觉”“知道”等概念误解的基础上。维特根斯坦通过语法分析成功地表明，“我知道我疼痛”这类句子与“我知道他疼痛”和“他知道我疼痛”并不属于同一种语言游戏，第一人称现在时话语的特权地位不应该在特权通道的意义上理解。

关键词：认知私人性内省意识知道语言游戏