Development of superconducting wind turbine generators
Bogi B. Jensen, Nenad Mijatovic, and Asger B. Abrahamsen
In this paper, the commercial activities in the field of superconducting machines, particularly superconducting wind turbine generators, are reviewed and presented. Superconducting generators have the potential to provide a compact and light weight drive train at high torques and slow rotational speeds, because high magnetic fields can be produced by coils with very little loss.
Improved performance of vanadium redox battery using methylsulfonic acid solution as supporting electrolyte
Zhangxing He, Zhen Li, Zhi Zhou, Feiyue Tu, Yifan Jiang, Chunyue Pan, and Suqin Liu
Methylsulfonic acid (MSA) as supporting electrolyte for vanadium redox battery was studied and evaluated by thermal stability test, cyclic voltammetry, linear sweep voltammetry, and charge-discharge technique. The results show that the V(V)-MSA solution has better thermal stability than the sulfuric acid solutions, which may be due to the formation of VO(CH3SO3)2 to prevent further condensation.
Nanoporous tin oxide photoelectrode prepared by electrochemical anodization in aqueous ammonia to improve performance of dye sensitized solar cell
Jun Jie Teh, Guan Hong Guai, Xuewan Wang, Kam Chew Leong, Chang Ming Li, and Peng Chen
In this work, a nanoporous thin film consisting of sieve-like tin oxide (SnO2) sheets was prepared by anodization of tin foil in aqueous ammonia and applied as a photoelectrode for dye-sensitized solar cell (DSSC). Compared to the conventional SnO2 nanoparticle-based photoelectrode, the anodized nanoporous SnO2 electrode offers higher short circuit current (6.85 vs. 3.64 mA/cm2) and open circuit voltage (0.56 vs. 0.51 V) due to better charge transportation and better suppression of charge recombination.
Validation of a FAST semi-submersible floating wind turbine numerical model with DeepCwind test data
Alexander J. Coulling, Andrew J. Goupee, Amy N. Robertson, Jason M. Jonkman, and Habib J. Dagher
There are global efforts in the offshore wind community to develop reliable floating wind turbine technologies that are capable of exploiting the abundant deepwater wind resource. These efforts require validated numerical simulation tools to predict the coupled aero-hydro-servo-elastic behavior of such systems.
Performance of hybrid compact filter system in a down-draft gasifier: An experimental study
Rameshkumar Ramasamy and Mayilsamy Kavandappa Gounder
Tar formation in biomass gasification is a major problem which in subsequent stages decomposes under the conditions such as temperature, pressure drop, gas flow rate, and retention time. Crucial review of literature discloses that all existing systems have maximum 90% tar removal capability.
Isotope effect in the photochemical decomposition of CO2 (ice) by Lyman-α radiation
Chunqing Yuan and John T. Yates, Jr.
The photochemical decomposition of CO2(ice) at 75 K by Lyman-α radiation (10.2 eV) has been studied using transmission infrared spectroscopy. An isotope effect in the decomposition of the CO2 molecule in the ice has been discovered, favoring 12CO2 photodecomposition over 13CO2 by about 10%.
Nonlinear femtosecond laser induced scanning tunneling microscopy
Shirshendu Dey, Daniel Mirell, Alejandro Rodriguez Perez, Joonhee Lee, and V. Ara Apkarian
The authors demonstrate ultrafast laser driven nonlinear scanning tunneling microscopy (STM), under ambient conditions. The design is an adaptation of the recently introduced cross-polarized double beat method, whereby z-polarized phase modulated fields are tightly focused at a tunneling junction consisting of a sharp tungsten tip and an optically transparent gold film as substrate.
Planar junctionless transistor with non-uniform channel doping
Partha Mondal, Bahniman Ghosh, and Punyasloka Bal
The authors propose a planar junctionless transistor (JLT) in silicon-on-insulator (SOI) with non-uniform channel doping in vertical direction to improve the ON to OFF drain current ratio. In single gate JLT in SOI, a thin device layer is depleted in the off-state from the top of the layer and the leakage current flows through bottom of the device layer, and the leakage current depends on the device layer thickness.
Band alignment in SnS thin-film solar cells: Possible origin of the low conversion efficiency
Lee A. Burton and Aron Walsh
Tin sulfide is an attractive absorber material for low-cost thin-film solar cells. Despite the ideal physical properties of bulk SnS, the photovoltaic conversion efficiencies achieved in devices to date have been no greater than 2%.
Tuning magnetic anisotropy in (001) oriented L10 (Fe1−xCux)55Pt45 films
Dustin A. Gilbert, Liang-Wei Wang, Timothy J. Klemmer, Jan-Ulrich Thiele, Chih-Huang Lai, and Kai Liu
The authors have achieved (001) oriented L10 (Fe1−xCux)55Pt45 thin films, with magnetic anisotropy up to 3.6 × 107 erg/cm3, using atomic-scale multilayer sputtering and post annealing at 400 °C for 10 s. By fixing the Pt concentration, structure and magnetic properties are systematically tuned by the Cu addition.