scholarly journals Inexpensive Graphene Oxide Heaters Lithographed by Laser

Nanomaterials ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 1184 ◽  
Author(s):  
Francisco J. Romero ◽  
Almudena Rivadeneyra ◽  
Inmaculada Ortiz-Gomez ◽  
Alfonso Salinas ◽  
Andrés Godoy ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Steady State ◽  
High Performance ◽  
Large Scale ◽  
Spray Deposition ◽  
Cost Effective ◽  
Fast Response ◽  
Stable Steady State ◽  
Steady State Temperature ◽  
High Level

In this paper, we present a simple and inexpensive method for the fabrication of high-performance graphene-based heaters on different large-scale substrates through the laser photothermal reduction of graphene oxide (laser-reduced graphene-oxide, LrGO). This method allows an efficient and localized high level of reduction and therefore a good electrical conductivity of the treated films. The performance of the heaters is studied in terms of steady-state temperature, power consumption, and time response for different substrates and sizes. The results show that the LrGO heaters can achieve stable steady-state temperatures higher than 200 °C when a voltage of 15 V is applied, featuring a time constant of around 4 s and a heat transfer coefficient of ~200 °C cm2/W. These characteristics are compared with other technologies in this field, demonstrating that the fabrication approach described in this work is competitive and promising to fabricate large-scale flexible heaters with a very fast response and high steady-state temperatures in a cost-effective way. This technology can be easily combined with other fabrication methods, such as screen printing or spray-deposition, for the manufacturing of complete sensing systems where the temperature control is required to adjust functionalities or to tune sensitivity or selectivity.

scholarly journals Ultrafast and Stable Planar Photodetector Based on SnS2 Nanosheets/Perovskite Structure

2021 ◽  
Author(s):  
Leyla Shooshtari ◽  
Ali Esfandiar ◽  
Yasin Orooji ◽  
Mahmoud Samadpour ◽  
Reza Rahighi
Keyword(s):  
High Performance ◽  
Large Scale ◽  
Incident Light ◽  
Transition Metal Dichalcogenides ◽  
Chemical Vapor ◽  
Cost Effective ◽  
Fast Response ◽  
Band Alignment ◽  
Perovskite Layer ◽  
Pmma Layer

Abstract Two-dimensional (2D) transition metal dichalcogenides (TMDs) are promising candidates of photodetectors where they are commonly grown parallel to the substrate due to their 2D characteristics in micrometer scales from exfoliation of bulk crystals or through high temperature chemical vapor deposition (CVD) methods. In this study, semi-hexagonal vertical nanosheets of SnS2 layered have been fabricated on FTO substrate without using Sn source through CVD method at relatively low temperature (500°C). Due to exceptional band alignment of triple cation lead perovskite with semi- hexagonal SnS2 nanosheets, an improved photodetector has been fabricated. This type of photodetectors fabricated through lithography-free and electrodes metallization free approach with remarkable fast response (20.7µs/31.4µs as rising /falling times), showed high photoresponsivity, external quantum efficiency and detectivity of 1.58 AW-1, 453% and 8.35 ×10 11, respectively under illumination of incident light ith 445nm. The stability of the photodetectors has been studied utilizing a protective PMMA layer on the perovskite layer in 100% humidity. The introduced growth and fabrication process of the planar photodetector, including one/two dimentional interface through the edges/ basal planes of layered materials with perovskite film, paves a way for the large scale, cost-effective and high-performance optoelectronic devices.

High-Performance Supercapacitors Based on ɛ-MnO2/RGO Fiber Electrodes for Wearable Energy Storage

2018 ◽  
Vol 18 (12) ◽  
pp. 8352-8359 ◽  
Author(s):  
Xibin Liu ◽  
Gaohua liao ◽  
Xiang Qi ◽  
Xiaoan Mei ◽  
Jifei Wang ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Energy Storage ◽  
High Performance ◽  
Fiber Surface ◽  
Current Collector ◽  
Cost Effective ◽  
Surface Acting ◽  
Energy Storage Devices ◽  
Hybrid Fibers ◽  
Storage Devices

Hybrid fibers based on MnO2/reduced graphene oxide have been fabricated for flexible energy storage devices. Graphene oxide nanoflakes were reduced in a polytetrafluoroethylene (PTFE) pipeline under the appropriate condition to develop a fiber current collector, which also provides the possibility of weaving. The RGO fiber with the radius of about 35 μm has a resistance of 150 Ω · cm. MnO2 nanoflakes directly grow on the RGO fiber surface acting as the electrode material of the device. The MnO2/RGO hybrid fibers provide excellent energy storage performances. The as-fabricated SC exhibits a high areal capacitance of 1.37 F·cm−2 at the scan rate of 1 mV·s−1, and outstanding long-term cycling stability of 93.75% retention after 5000 cycles. This work demonstrates a cost-effective and versatile strategy for wearable energy storage devices.

Making E-Training Cost Effective through Quality Assurance

2009 ◽  
pp. 623-631
Author(s):  
Lichia Yiu ◽  
Raymond Saner
Keyword(s):  
High Performance ◽  
Cost Effective ◽  
Web Based ◽  
Corporate Learning ◽  
Use Of Technology ◽  
Training Cost ◽  
E Learning ◽  
American Society ◽  
High Level ◽  
The Cost

Since the 1990s, more and more corporate learning has been moved online to allow for flexibility, just-in-time learning, and cost saving in delivering training. This trend has been evolved along with the introduction of Web-based applications for HRM purposes, known as electronic Human Resource Management (e-HRM). By 2005, 39.67% of the corporate learning, among the ASTD (American Society for Training and Development) benchmarking forum companies, was delivered online in comparison to 10.5% in 2001. E-learning has now reached “a high level of (technical) sophistication, both in terms of instructional development and the effective management of resources” in companies with high performance learning function (ASTD, 2006, p.4). The cost per unit, reported by ASTD in its 2006 State of Industry Report, has been declining since 2000 despite the higher training hours received per employee thanks to the use of technology based training delivery and its scalability. However, the overall quality of e-learning either public available in the market or implemented at the workplace remains unstable.

scholarly journals Fabrication and Characterization of Humidity Sensors Based on Graphene Oxide–PEDOT:PSS Composites on a Flexible Substrate

Micromachines ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 148 ◽  
Author(s):  
Francisco J. Romero ◽  
Almudena Rivadeneyra ◽  
Markus Becherer ◽  
Diego P. Morales ◽  
Noel Rodríguez
Keyword(s):  
Graphene Oxide ◽  
Large Scale ◽  
Flexible Substrate ◽  
High Sensitivity ◽  
Cost Effective ◽  
Humidity Sensors ◽  
Good Thermal Stability ◽  
Cost Effective Method ◽  
And Performance ◽  
Stability Time

In this paper, we present a simple, fast, and cost-effective method for the large-scale fabrication of high-sensitivity humidity sensors on flexible substrates. These sensors consist of a micro screen-printed capacitive structure upon which a sensitive layer is deposited. We studied two different structures and three different sensing materials by modifying the concentration of poly(3,4-ethylenedioxythiophene)/polystyrene sulfonate (PEDOT:PSS) in a graphene oxide (GO) solution. The results show that the aggregation of the PEDOT:PSS to the GO can modify its electrical properties, boosting the performance of the capacitive sensors in terms of both resistive losses and sensitivity to relative humidity (RH) changes. Thus, in an area less than 30 mm2, the GO/PEDOT:PSS-based sensors can achieve a sensitivity much higher (1.22 nF/%RH at 1 kHz) than other similar sensors presented in the literature which, together with their good thermal stability, time response, and performance over bending, demonstrates that the manufacturing approach described in this work paves the way for the mass production of flexible humidity sensors in an inexpensive way.

scholarly journals Towards High Performance Chemical Vapour Deposition V2O5 Cathodes for Batteries Employing Aqueous Media

Molecules ◽  
2020 ◽  
Vol 25 (23) ◽  
pp. 5558
Author(s):  
Dimitra Vernardou ◽  
Charalampos Drosos ◽  
Andreas Kafizas ◽  
Martyn E. Pemble ◽  
Emmanouel Koudoumas
Keyword(s):  
Energy Storage ◽  
High Performance ◽  
Large Scale ◽  
Electrode Materials ◽  
Low Cost ◽  
Aqueous Media ◽  
Chemical Vapour ◽  
Cost Effective ◽  
Scale Production ◽  
Environmentally Safe

The need for clean and efficient energy storage has become the center of attention due to the eminent global energy crisis and growing ecological concerns. A key component in this effort is the ultra-high performance battery, which will play a major role in the energy industry. To meet the demands in portable electronic devices, electric vehicles, and large-scale energy storage systems, it is necessary to prepare advanced batteries with high safety, fast charge ratios, and discharge capabilities at a low cost. Cathode materials play a significant role in determining the performance of batteries. Among the possible electrode materials is vanadium pentoxide, which will be discussed in this review, due to its low cost and high theoretical capacity. Additionally, aqueous electrolytes, which are environmentally safe, provide an alternative approach compared to organic media for safe, cost-effective, and scalable energy storage. In this review, we will reveal the industrial potential of competitive methods to grow cathodes with excellent stability and enhanced electrochemical performance in aqueous media and lay the foundation for the large-scale production of electrode materials.

The Production of Reduced Graphene Oxide by a Low-Cost Vacuum System for Supercapacitor Applications

2018 ◽  
Vol 930 ◽  
pp. 609-612
Author(s):  
Quezia Cardoso ◽  
Franks Martins Silva ◽  
Ligia Silverio Vieira ◽  
Julio Cesar Serafim Casini ◽  
Solange Kazume Sakata ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Large Scale ◽  
Low Cost ◽  
High Vacuum ◽  
Cost Effective ◽  
Practical Method ◽  
Raw Material ◽  
Vacuum System ◽  
X Ray ◽  
Pump Pressure

Graphene has attracted significant interest because of its excellent electrical properties. However, a practical method for producing graphene on a large scale is yet to be developed. Graphene oxide (GO) can be partially reduced to graphene-like sheets by removing the oxygen-containing groups and recovering the conjugated structure. GO can be produced using inexpensive graphite as the raw material via cost-effective chemical methods. High vacuum and temperature (10−7 mbar and 1100°C, respectively) conditions are well-known to enable the preparation of reduced powder at the laboratory scale. However, a large-scale high vacuum reduction system that can be routinely operated at 10−7 mbar requires considerable initial capital as well as substantial operational and maintenance costs. The current study aims at developing an inexpensive method for the large-scale reduction of graphene oxide. A stainless steel vessel was evacuated to backing-pump pressure (10−2 mbar) and used to process GO at a range of temperatures. The reduction of GO powder at low vacuum pressures was attempted and investigated by X-ray diffraction and Fourier transform infrared spectroscopy. The experimental results of processing GO powder at various temperatures (200–1000°C) at relatively low pressures are reported. The microstructures of the processed materials were investigated using scanning electron microscopy and chemical microanalyses via energy dispersive X-ray analysis.

Large scale synthesized sulphonated reduced graphene oxide: a high performance material for electrochemical capacitors

RSC Advances ◽  
2013 ◽  
Vol 3 (35) ◽  
pp. 14954 ◽  
Author(s):  
Haibo Li ◽  
Ye Wang ◽  
Yumeng Shi ◽  
Jin Li ◽  
Lijun He ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Reduced Graphene Oxide ◽  
High Performance ◽  
Large Scale ◽  
Electrochemical Capacitors ◽  
Reduced Graphene

scholarly journals Performance Analysis of Specification Computer and Mobile with Implementation Tawaf Virtual Reality using A* Algorithm and RVO System

2019 ◽  
Vol 7 (1) ◽  
pp. 55-70
Author(s):  
Moh. Zikky ◽  
M. Jainal Arifin ◽  
Kholid Fathoni ◽  
Agus Zainal Arifin
Keyword(s):  
Virtual Reality ◽  
High Performance ◽  
Large Scale ◽  
3D Models ◽  
A Algorithm ◽  
Virtual Reality Technology ◽  
Performance Technology ◽  
Outer Line ◽  
High Performance Computer ◽  
High Level

High-Performance Computer (HPC) is computer systems that are built to be able to solve computational loads. HPC can provide a high-performance technology and short the computing processes timing. This technology was often used in large-scale industries and several activities that require high-level computing, such as rendering virtual reality technology. In this research, we provide Tawaf’s Virtual Reality with 1000 of Pilgrims and realistic surroundings of Masjidil-Haram as the interactive and immersive simulation technology by imitating them with 3D models. Thus, the main purpose of this study is to calculate and to understand the processing time of its Virtual Reality with the implementation of tawaf activities using various platforms; such as computer and Android smartphone. The results showed that the outer-line or outer rotation of Kaa’bah mostly consumes minimum times although he must pass the longer distance than the closer one.  It happened because the agent with the closer area to Kaabah is facing the crowded peoples. It means an obstacle has the more impact than the distances in this case.

scholarly journals Cloud Computing Cloud Computing in Remote Sensing : High Performance Remote Sensing Data Processing in a Big data Environment

2021 ◽  
Vol 16 (6) ◽  
Author(s):  
Yassine Sabri ◽  
Aouad Siham
Keyword(s):  
Remote Sensing ◽  
Cloud Computing ◽  
Data Processing ◽  
High Performance ◽  
Large Scale ◽  
Processing System ◽  
Remote Sensing Data ◽  
Cloud Service ◽  
Intermediate Data ◽  
High Level

Multi-area and multi-faceted remote sensing (SAR) datasets are widely used due to the increasing demand for accurate and up-to-date information on resources and the environment for regional and global monitoring. In general, the processing of RS data involves a complex multi-step processing sequence that includes several independent processing steps depending on the type of RS application. The processing of RS data for regional disaster and environmental monitoring is recognized as computationally and data demanding.Recently, by combining cloud computing and HPC technology, we propose a method to efficiently solve these problems by searching for a large-scale RS data processing system suitable for various applications. Real-time on-demand service. The ubiquitous, elastic, and high-level transparency of the cloud computing model makes it possible to run massive RS data management and data processing monitoring dynamic environments in any cloud. via the web interface. Hilbert-based data indexing methods are used to optimally query and access RS images, RS data products, and intermediate data. The core of the cloud service provides a parallel file system of large RS data and an interface for accessing RS data from time to time to improve localization of the data. It collects data and optimizes I/O performance. Our experimental analysis demonstrated the effectiveness of our method platform.

scholarly journals Upstream to downstream: a multiple-assessment-point approach for targeting non-point-source priority management areas at large watershed scale

2013 ◽  
Vol 10 (11) ◽  
pp. 14535-14555
Author(s):  
L. Chen ◽  
Y. Zhong ◽  
G. Wei ◽  
Z. Shen
Keyword(s):  
Point Source ◽  
Large Scale ◽  
Cost Effective ◽  
Small Scale ◽  
Watershed Scale ◽  
Nps Pollution ◽  
Specific Assessment ◽  
High Level ◽  
Multiple Assessment

Abstract. The identification of priority management areas (PMAs) is essential for the control of non-point source (NPS) pollution, especially for a large-scale watershed. However, previous studies have typically focused on small-scale catchments adjacent to specific assessment points; thus, the interactions between multiple river points remain poorly understood. In this study, a multiple-assessment-point PMA (MAP-PMA) framework was proposed by integrating the upstream sources and the downstream transport aspects of NPS pollution. Based on the results, the integration of the upstream input changes was vital for the final PMAs map, especially for downstream areas. Contrary to conventional wisdom, this research recommended that the NPS pollutants could be best controlled among the upstream high-level PMAs when protecting the water quality of the entire watershed. The MAP-PMA framework provided a more cost-effective tool for the establishment of conservation practices, especially for a large-scale watershed.

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