http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
A ZnO nanowire-based photo-inverter with pulse-induced fast recovery.
Raza, Syed Raza Ali,Lee, Young Tack,Hosseini Shokouh, Seyed Hossein,Ha, Ryong,Choi, Heon-Jin,Im, Seongil RSC Pub 2013 Nanoscale Vol.5 No.22
<P>We demonstrate a fast response photo-inverter comprised of one transparent gated ZnO nanowire field-effect transistor (FET) and one opaque FET respectively as the driver and load. Under ultraviolet (UV) light the transfer curve of the transparent gate FET shifts to the negative side and so does the voltage transfer curve (VTC) of the inverter. After termination of UV exposure the recovery of photo-induced current takes a long time in general. This persistent photoconductivity (PPC) is due to hole trapping on the surface of ZnO NWs. Here, we used a positive voltage short pulse after UV exposure, for the first time resolving the PPC issue in nanowire-based photo-detectors by accumulating electrons at the ZnO/dielectric interface. We found that a pulse duration as small as 200 ns was sufficient to reach a full recovery to the dark state from the UV induced state, realizing a fast UV detector with a voltage output.</P>
Raza, Syed Abbas,Karim, Muhammad Ramzan Abdul,Shehbaz, Tauheed,Taimoor, Aqeel Ahmad,Ali, Rashid,Khan, Muhammad Imran The Korean Electrochemical Society 2022 Journal of electrochemical science and technology Vol.13 No.2
In the present study, the corrosion behavior of aluminum Al-7075 tempered (T-6 condition) alloy was evaluated by immersion testing and electrochemical testing in 1.75% and 3.5% NaCl environment at acidic, neutral and basic pH. The data obtained by both immersion tests and electrochemical corrosion tests (potentiodynamic polarization and electrochemical impedance spectroscopy tests) present that the corrosion rate of the alloy specimens is minimum for the pH=7 condition of the solution due to the formation of dense and well adherent thin protective oxide layer. Whereas the solutions with acidic and alkaline pH cause shift in the corrosion behavior of aluminum alloy to more active domains aggravated by the constant flux of acidic and alkaline ions (Cl<sup>-</sup> and OH<sup>-</sup>) in the media which anodically dissolve the Al matrix in comparison to precipitated intermetallic phases (cathodic in nature) formed due to T6 treatment. Consequently, the pitting behavior of the alloy, as observed by cyclic polarization tests, shifts to more active regions when pH of the solutions changes from neutral to alkaline environment due to localized dissolution of the matrix in alkaline environment that ingress by diffusion through the pores in the oxide film. Microscopic analysis also strengthens the results obtained by immersion corrosion testing and electrochemical corrosion testing as the study examines the corrosion behavior of this alloy under a systematic evaluation in marine environment.
Syed Raza 부산대학교 한국민족문화연구소 2017 Localities Vol.7 No.-
Traditional mountain societies are characterized by their symbiotic relationships with nature. Living in harsh environments, these peoples have to rely on natural resources and an array of practices which they have devised through trial and error through the ages. Their holistic view of their ecosystem results in diversified and dynamic strategies that are well adapted to both their natural environment and culture. Therefore, these peoples can be seen as guardians of the common resources around them. They procure and maintain such resources in accordance with their particular cultural edicts. This paper is based on ethnographic data collected from the village of Jangi in Kinnaur District of India’s Himachal Pradesh province, and documents how villagers are able to sustainable themselves through the religious intervention of the Deota (deity) Committee and the “Village Gram Sabha,” which regulate the water supplies for fields and distribute the forest’s dry fruits. The paper combines economic and cultural factors to analyze how traditional societies today use their sustainable practices to enhance their chances of survival in the harshest of conditions. It also enlightens readers about how women are distributors of knowledge in a mountain ecology, thus enabling future generations to survive well.
5G NR mmWave Indoor Coverage with Massive Antenna System
Syed Hassan Raza Naqvi,Pin Han Ho,Limei Peng 한국통신학회 2021 Journal of communications and networks Vol.23 No.1
In this paper, we introduce a novel mmWave access architecture,called mmWave over cable (mmWoC), for achieving effectiveindoor coverage, which is characterized by using an analogmodulated relay link to transport the outdoor mmWave signalsto the indoors. To enable an effective mapping of radio signals onthe cable sub-carriers, we introduce non-configurable air-to-cable(NC-A2C) scheduler that is characterized by its low control complexityand hardware requirement. We will discuss the merits ofthe proposed mmWoC access architecture and the NC-A2C scheduler,which are further validated via extensive simulations.
Tool Wear Patterns When Turning of Titanium Alloy Using Sustainable Lubrication Strategies
Syed Waqar Raza,Ibrahim Deiab,Salman Pervaiz 한국정밀공학회 2014 International Journal of Precision Engineering and Vol. No.
A key area of research in sustainable machining is the search for environmentally benign cooling strategies. Vegetable oils have oftenbeen proposed as sustainable alternative to the conventional synthetic emulsion coolants. Techniques like dry and cryogenicmachining, MQL and MQCL have also been proposed. The current study investigates the effect of six different strategies on the flanktool wear during turning of titanium Ti-6Al-4v using uncoated carbide tool at two levels of speed and feed. The mechanisms of toolwear are discussed. The use of rapeseed vegetable oil in MQL and MQCL configuration turns out to be an overall sustainablealternative at low feed and speed. Thus confirming the promise predicted in the use of vegetable oil as a lubricant for machining. At high speed and feed, cryogenic machining is more suitable for sustainable machining of Titanium.