Local Hall effect in hybrid ferromagnetic/semiconductor devices

We have investigated the magnetoresistance of ferromagnet-semiconductor devices in an InAs two-dimensional electron gas system in which the magnetic field has a sinusoidal profile. The magnetoresistance of our device is large. The longitudinal resistance has an additional contribution which is odd in applied magnetic field. It becomes even negative at low temperature where the transport is ballistic. Based on the numerical analysis, we confirmed that our data can be explained in terms of the local Hall effect due to the profile of negative and positive field regions. This device may be useful for future spintronic applications.Comment: 4 pages with 4 fugures. Accepted for publication in Applied Physics Letter

Wall : A wall of Curious Interactions

The current model of housing is ill-suited to address the epidemic of loneliness and isolation. The top – down approaches to the built environment serialize the social needs of the urban metropolis as an issue of density. As such, the housing has turned to a highly marketable and easily organized model of tower housing. However, highly organizational models struggle to design for the nuanced and messy aspects of social interactions, resulting in an overly isolative and oppressive form of living. Architecture can no longer afford a typology that discourages means of spontaneous interaction. Instead, this project argues for a dwelling that encourages connections in the form of co-op housing. Designing for a non-isolative privacy and interactions of curiosity, it positions the wall at the center as means to develop relationships. Therefore, it is a reaction against the isolative wall typical to the current forms of tower housing. The project aims to redefine the wall as an interface for curious interactions that facilitate engagement with one’s neighbor.Applied Science, Faculty ofArchitecture and Landscape Architecture (SALA), School ofUnreviewedGraduat

Visualization 5: Fiber bundle-based integrated platform for wide-field fluorescence imaging and patterned optical stimulation for modulation of vasoconstriction in the deep brain of a living animal

Video of vasoconstriction in a single cerebral blood vessel using patterned light stimulation at 4.7 mm below the cortical surface of living ChR2 transgenic mouse (SM22(CAG-ChR2-EYFP)). Originally published in Biomedical Optics Express on 01 June 2017 (boe-8-6-2781

Separation of Co(II) and Li(I) with Cyanex 272 using hollow fiber supported liquid membrane: A comparison with flat sheet supported liquid membrane and dispersive solvent extraction process

Separation of Co(II) and Li(I) by non-dispersive solvent extraction using a hollow fiber supported liquid membrane has been investigated. Separation of both the metals by flat sheet supported liquid membrane and dispersive solvent extraction technique has also been investigated and compared. The parameters for the three processes were optimized to achieve quantitative separation of Co(II) over Li(I) with Cyanex 272 diluted with kerosene. The feasibility to produce pure metal salt solutions was established by controlling the process parameters like pH of the feed solution, extractant concentration, metal ion concentration and acid concentration for selective stripping. For both the hollow fiber and the flat sheet supported liquid membrane processes, the aqueous feed pH of 6.0 and 750 mol/m(3) of Cyanex 272 in the membrane phase were the best conditions for extraction, whereas the best stripping results were obtained with 100 and 25 mol/m(3) H2SO4, respectively. In the case of dispersive solvent extraction process, the quantitative separation of the metals was achieved by extraction at equilibrium pH of 5.50 using 100 mol/m(3) of Cyanex 272, and stripping with 10 mol/m(3) H2SO4 solution. Under the optimum conditions, the separation factor was found to be 18, 178 and 180 for hollow fiber supported liquid membrane, flat sheet supported liquid membrane, and dispersive solvent extraction, respectively. Suitable mathematical models for the quantitative extraction of the metal in dispersive solvent extraction and mass-transfer coefficient in non-dispersive solvent extraction were proposed and validity of the models was verified. Proposed models and the mathematical analyses revealed that both dispersive solvent extraction and non-dispersive solvent extraction process followed cation-exchange reaction mechanism with similar kind of stoichiometry. (C) 2015 Elsevier B.V. All rights reserved

Visualization 1: Fiber bundle-based integrated platform for wide-field fluorescence imaging and patterned optical stimulation for modulation of vasoconstriction in the deep brain of a living animal

FITC fluorescence cerebrovascular video with bleeding due to vessel damage by excessive insertion of a 620-µm fiber bundle into the brain of living B6 wild-type adult mouse. Originally published in Biomedical Optics Express on 01 June 2017 (boe-8-6-2781

Performance Comparison of CdTe:Na, CdTe:As, and CdTe:P Single Crystals for Solar Cell Applications

We compared thermal stability, open-circuit voltage, short-circuit current, and fill factor values of single-crystal Cadmium telluride (CdTe) grown using the vertical Bridgman (VB) technique and doped with group V elements (phosphorus and arsenic), and group Ⅰ element (sodium), followed by an annealing process. The sodium-doped CdTe maintained a hole density of 1016 cm−3 or higher; after annealing for a long time, this decreased to 1015 cm−3 or less. The arsenic-doped CdTe maintained a hole density of approximately 1016 cm−3 even after the annealing process; however its bulk minority carrier lifetime decreased by approximately 10%. The phosphorus-doped CdTe maintained its properties after the annealing process, ultimately achieving a hole density of ~1016 cm−3 and a minority carrier lifetime of ~40 ns. The characteristics of a single-crystal solar cell were evaluated using a solar cell device that contained single-crystal CdTe with various dopants. The sodium-doped sample exhibited poor interfacial properties, and its performance decreased rapidly during annealing. The samples doped with group V elements exhibited stable characteristics even during long-term annealing. We concluded, therefore, that group V elements dopants are more suitable for CdTe single-crystal-based solar cell applications involving thermal stress conditions, such as space missions or extreme fabrication temperature environments

Smart paper electronics by laser-induced graphene for biodegradable real-time food spoilage monitoring

In situ monitoring system on the food package based on biodegradable materials to examine the food status is of great significance for practical application since food poisoning and non-degradable package waste have raised critical healthcare and environmental issues recently. Here, we report a laser-induced paper sensor (LIPS) that is comprised of a laser-induced graphene (LIG)/paper hybrid structure for wireless, real-time monitoring of the food status by the chemical- and thermo- sensing capabilities of LIPS. Direct laser irradiation on any type or structure of commercial paper converts the laser-irradiated paper surface into LIPS with a decent sheet resistance of 105 omega sq(-1) and porous structure which enables smart monitoring of key parameters such as gas concentration and temperature for the food spoilage prior to the food intake. Optimized laser irradiation conditions on the paper substrate produced the temperature and chemical gas coefficient of resistance change of 0.15%degrees C-1 and 0.0041% ppm(-1). As a proof-of-concept, we fabricated LIPS on the surface of the paper to both detect the temperature and monitor the chemical degradation of the food, of which data can be directly delivered to the user's mobile device through continuous wireless communication. We believe that LIPS proposed herein will make significant contributions to the next-generation food-related green electronics to provide users with a smart and high-fidelity monitoring platform for simple detection of the real-time status of food products.N