793 research outputs found
Microwave oven fabricated hybrid memristor devices for non-volatile memory storage
© 2014 IOP Publishing Ltd. Novel hybrid non-volatile memories made using an ultra-fast microwave heating method are reported for the first time. The devices, consisting of aligned ZnO nanorods embedded in poly (methyl methacrylate), require no forming step and exhibit reliable and reproducible bipolar resistive switching at low voltages and with low power usage. We attribute these properties to a combination of the high aspect ratio of the nanorods and the polymeric hybrid structure of the device. The extremely easy, fast and low-cost solution based method of fabrication makes possible the simple and quick production of cheap memory cells
Novel conducting polymer current limiting devices for low cost surge protection applications
We report on the development of novel intrinsic conducting polymer two terminal surge protection devices. These resettable current limiting devices consist of polyaniline nanofibres doped with methane sulphonic acid electrochemically deposited between two 55 μm spaced gold electrodes. At normal applied voltages, the low resistance devices act as passive circuit elements, not affecting the current flow. However during a current surge the devices switch from ohmic to non-ohmic behaviour, limiting current through the device. After the current surge has passed, the devices reset back to their original state. Our studies show that a partial de-doping/re-doping process caused by the rapid diffusion of moisture out of or into the polymer film during joule heating/cooling is the underlying mechanism responsible
Super hydrophobic SAM modified electrodes for enhanced current limiting properties in intrinsic conducting polymer surge protection devices
Surface interface engineering using superhydrophobic gold electrodes made with 1-dodecanethiol self-assembled monolayer (SAM) has been used to enhance the current limiting properties of novel surge protection devices based on the intrinsic conducting polymer, polyaniline doped with methanesulfonic acid. The resulting devices show significantly enhanced current limiting characteristics, including current saturation, foldback, and negative differential effects. We show how SAM modification changes the morphology of the polymer film directly adjacent to the electrodes, leading to the formation of an interfacial compact thin film that lowers the contact resistance at the Au−polymer interface. We attribute the enhanced current limiting properties of the devices to a combination of lower contact resistance and increased Joule heating within this interface region which during a current surge produces a current blocking resistive barrier due to a thermally induced dedoping effect caused by the rapid diffusion of moisture away from this region. The effect is exacerbated at higher applied voltages as the higher temperature leads to stronger depletion of charge carriers in this region, resulting in a negative differential resistance effec
Contracts - Licensing - The Lanham Act Does Provide a Remedy for a False Sponsorship Claim - Mastercard International, Inc. v. Sprint Communications, Co., No. 94 CIV. 1051(JSM), 1994 WL 97097 (S.D.N.Y. Mar. 23, 1994).
Large dopant dependence of the current limiting properties of intrinsic conducting polymer surge protection devices
New two terminal surge protection devices based on intrinsic conducting polymers are demonstrated to be strongly affected by the dopant molecule type. Thermogravimetric analysis combined with current–voltage studies show a causal link between the dopant molecule, moisture content and the current limiting capability of the devices. Polyaniline thin-films with high moisture content produce devices with current saturation and foldback effects at high applied voltages while low moisture content films exhibit no current rectification and instead demonstrate decreasing resistivity with increasing voltage. Polyaniline doped with sulfuric acid (H2SO4) exhibited the largest moisture content and surge protection devices built with this material produced for the first time negative differential resistance under ambient conditions. A further improvement was made upon this through surface engineering of the interface between the polymer and electrodes using self-assembled monolayers
Anthropology of the Crowd
Faculty reflection on VCU Great Bike Race Book course.
Course Description: This track will study the bike race crowd using the four fields of anthropology (archaeology, biological, linguistic and sociocultural) to discover how they represent the greater diversity of humanity
Impact of sludge floc size and water composition on dewaterability
In order to observe the impact of different water compositions on sludge dewaterability, assessments of floc sizes using a particle size analyzer and of sludge dewaterability based on the capillary suction time (CST) test were carried out. Synthetic raw water had small floc sizes, and synthetic domestic wastewater had both larger median floc sizes and a better correlation between sludge dewaterability and median floc sizes. The floc size distribution results showed that synthetic raw water is associated with a narrow particle size distribution. In comparison, synthetic domestic wastewater produced a wider distribution. However, the CST values were similar for both waters. Compared to synthetic wastewater, natural wastewater had the largest distribution with generally larger particle sizes
The Coronavirus 2019 Pandemic Impact on the United States Public Universities
Since Covid-19 pandemic started in 2020, colleges and universities had to change the way students have a college experience. I used data and statistics to support claims in sub-topics throughout my paper such as club recruitment, student involvement, a Coronavirus 19 pandemic timeline, online learning outcomes, mental health, and funding of higher education. I had also interviewed Purchase College students and turned my own personal experience into a case study. Most importantly, I had created a Purchase College tool-kit for students that have been struggling to get involved in the community.Purchase College SUNYArts ManagementBachelor of ArtsGibson-Brehon, Dawn D
New Challenges in the Mathematical Modelling and Control of COVID-19 Epidemics: Analysis of Non-Pharmaceutical Actions and Vaccination Strategies
Following its official appearance in China in December 2019, COVID-19 (SARS-CoV-2) infection immediately reached pandemic proportions on six continents and in over 195 countries [...
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