Hasil untuk "Technology"

G. Bulman, R. Fairlie

N. Park

Perovskite solar cells based on organometal halides represent an emerging photovoltaic technology. Perovskite solar cells stem from dye-sensitized solar cells. In a liquid-based dye-sensitized solar cell structure, the adsorption of methylammonium lead halide perovskite on a nanocrystalline TiO2 surface produces a photocurrent with a power conversion efficiency (PCE) of around 3–4%, as first discovered in 2009. The PCE was doubled after 2 years by optimizing the perovskite coating conditions. However, the liquid-based perovskite solar cell receives little attention because of its stability issues, including instant dissolution of the perovskite in a liquid electrolyte. A long-term, stable, and high efficiency (∼10%) perovskite solar cell was developed in 2012 by substituting the solid hole conductor with a liquid electrolyte. Efficiencies have quickly risen to 18% in just 2 years. Since PCE values over 20% are realistically anticipated with the use of cheap organometal halide perovskite materials, perovskite solar cells are a promising photovoltaic technology. In this review, the opto-electronic properties of perovskite materials and recent progresses in perovskite solar cells are described. In addition, comments on the issues to current and future challenges are mentioned.

Zizi Papacharissi

B. Sridevi

Wayne F. Cascio, Ramiro Montealegre

V. Packard

Peggy A. Ertmer, Anne T. Ottenbreit-Leftwich

M. R. Dunn, Randi M. Jimenez, J. Chaput

Zhuhua Zhang, Xuemei Li, Jun Yin et al.

G. Burdea, Philippe Coiffet

P. H. Hu, Patrick Y. K. Chau, O. R. Sheng et al.

A. Parasuraman, Dhruv Grewal

Stephen D. Oliner, Daniel Sichel, Daniel Sichel

W. Bijker, T. P. Hughes, T. Pinch

M. Borup, N. Brown, Kornelia Konrad et al.

L. Gyongyosi, S. Imre

Abstract The power of quantum computing technologies is based on the fundamentals of quantum mechanics, such as quantum superposition, quantum entanglement, or the no-cloning theorem. Since these phenomena have no classical analogue, similar results cannot be achieved within the framework of traditional computing. The experimental insights of quantum computing technologies have already been demonstrated, and several studies are in progress. Here we review the most recent results of quantum computation technology and address the open problems of the field.

A. Bogaerts, E. Neyts

Wei Li, Bingnan Mu, Yiqi Yang

This review emphasizes the importance of costs in industrial-scale treatment of dye wastewater and provides a way to assess the cost-based feasibility of bio-adsorption technologies. Dye wastewater is one of the major contributors to environmental pollution. Bio-adsorption has attracted considerable attentions in dye wastewater treatment due to its technical feasibility, flexibility and operation simplicity. However, industrial-scale treatment of dye wastewater via bio-adsorption technologies remains stagnant, mainly due to high costs. So far, no review or research articles have systematically discussed the criteria for successful utilization of bio-adsorption technologies on a large scale. This review discusses the major factors affecting adsorption and desorption performance based on basic chemical and physical structures of bio-adsorbents available in literatures. A quantitative relationship has been summarized based on previous studies to assess the cost to utilize a bio-adsorption technology and serve as an access threshold for quality bio-adsorbents to be taken into real applications.

T. Kandil, S. Nassar, Mohamed Taysir

Blockchain technology starts to reconfigure all aspects of society to make it clear and beneficial for the legal system. The chapter introduces “The Blockchain Revolution” in categories 1.0, 2.0, and 3.0; in the form of analyzing the use of the technology that is being applied in new innovative business models, Blockchain 1.0 starts with the creation of the first blockchain and the introduction of the technology in the “Bitcoin Whitepaper,” the crypto-currency model, via Bitcoin's application in services related to cash, payments, and transfers. Blockchain 2.0 starts with the indication that using smart contracts on blockchains will be available via the development of syntax (i.e., “solidity” that would enable developers to create solutions with blockchain technology at the backend). The chapter explores the feature of the new disruptive business models-based blockchain technology as a new approach in delivering business products and services. In the chapter, the authors explore the new technologies raised in different fields of business.

J. Gudmundsson

Magnetron sputtering deposition has become the most widely used technique for deposition of both metallic and compound thin films and is utilized in numerous industrial applications. There has been a continuous development of the magnetron sputtering technology to improve target utilization, increase ionization of the sputtered species, increase deposition rates, and to minimize electrical instabilities such as arcs, as well as to reduce operating cost. The development from the direct current (dc) diode sputter tool to the magnetron sputtering discharge is discussed as well as the various magnetron sputtering discharge configurations. The magnetron sputtering discharge is either operated as a dc or radio frequency discharge, or it is driven by some other periodic waveforms depending on the application. This includes reactive magnetron sputtering which exhibits hysteresis and is often operated with an asymmetric bipolar mid-frequency pulsed waveform. Due to target poisoning the reactive sputter process is inherently unstable and exhibits a strongly non-linear response to variations in operating parameters. Ionized physical vapor deposition was initially achieved by adding a secondary discharge between the cathode target and the substrate and later by applying high power pulses to the cathode target. An overview is given of the operating parameters, the discharge properties and the plasma parameters including particle densities, discharge current composition, electron and ion energy distributions, deposition rate, and ionized flux fraction. The discharge maintenance is discussed including the electron heating processes, the creation and role of secondary electrons and Ohmic heating, and the sputter processes. Furthermore, the role and appearance of instabilities in the discharge operation is discussed.