Fast switching times of KD2PO4-KH2AsO4ferroelectric domains monitored by ESR

1983 ◽  
Vol 28 (9) ◽  
pp. 5268-5272 ◽  
Author(s):  
Roger D. Truesdale ◽  
Horacio A. Farach ◽  
Charles P. Poole
Keyword(s):  
Fast Switching ◽  
Switching Times

Design Method for Fast Switching Seat Valves for Digital Displacement® Machines

2014 ◽  
Author(s):  
Daniel B. Roemer ◽  
Per Johansen ◽  
Henrik C. Pedersen ◽  
Torben O. Andersen
Keyword(s):  
Pressure Loss ◽  
Design Method ◽  
Thermal Dissipation ◽  
Valve Design ◽  
Stroke Length ◽  
Efficient Operation ◽  
Fast Switching ◽  
Switching Times ◽  
High Bandwidth ◽  
Electro Magnetic

Digital Displacement® (DD) machines are upcoming technology where the displacement of each pressure chamber is controlled electronically by use of two fast switching seat valves. The effective displacement and operation type (pumping/motoring) may be controlled by manipulating the seat valves corresponding to the piston movement, which has been shown to facilitate superior part load efficiency combined with high bandwidth compared to traditional displacement machines. However, DD machines need fast switching on-off valves with low pressure loss for efficient operation, especially in fast rotating operation, where switching times must be performed within a few milliseconds. These valve requirements make a simulation based design approach essential, where mechanical strength, thermal dissipation, fluid dynamics and electro-magnetic dynamics must be taken into account. In this paper a complete design method for DD seat valves are presented, taking into account the significant aspects related to obtaining efficient DD valves with basis in a given DD machine specifications. The seat area is minimized and the stroke length is minimized to obtain fast switching times while considering the pressure loss of the valves. A coupled optimization is finally conducted to optimize the electro-magnetic actuator, leading to a valve design based on the chosen valve topology. The design method is applied to an example DD machine and the resulting valve design fulfilling the requirements is presented.

Ferroelektrische Flüssigkristall - Mischungen mit Kohlenhydrat - Derivaten als Dotierstoffe / Ferroelectric Liquid Crystal Mixtures with Carbohydrate Derivates as Dopants

1989 ◽  
Vol 44 (7) ◽  
pp. 675-679 ◽  
Author(s):  
V. Vill ◽  
F. Fischer ◽  
J. Thiem
Keyword(s):  
Liquid Crystal ◽  
Chiral Center ◽  
Ferroelectric Liquid Crystal ◽  
Fast Switching ◽  
Switching Times ◽  
Smectic Phases ◽  
First Time ◽  
Helical Twisting Power

Abstract For the first time carbohydrate derivatives were studied as dopants for calamitic smectic phases. Fast switching ferroelectric cells could be realized, and electroclinic effects were observed. By inversion of configuration at a chiral center of these compounds switching times, solubility, and helical twisting power vary by orders of magnitude. The studied derivatives showed modest solubility properties.

High-performance electrochromic films with fast switching times using transparent/conductive nanoparticle-modulated charge transfer

Nanoscale ◽  
2019 ◽  
Vol 11 (38) ◽  
pp. 17815-17830 ◽  
Author(s):  
Junsang Yun ◽  
Yongkwon Song ◽  
Ikjun Cho ◽  
Yongmin Ko ◽  
Cheong Hoon Kwon ◽  
...  
Keyword(s):  
Charge Transfer ◽  
Transition Metal ◽  
Metal Oxide ◽  
High Performance ◽  
Transition Metal Oxide ◽  
Fast Switching ◽  
Switching Times

Facile charge transfer-induced structural/interfacial designs for high-performance transition metal oxide-based electrochromic films.

Liquid-crystal varactors with fast switching times for microwave applications

2008 ◽  
Vol 44 (7) ◽  
pp. 480 ◽  
Author(s):  
F. Goelden ◽  
A. Gaebler ◽  
S. Mueller ◽  
A. Lapanik ◽  
W. Haase ◽  
...  
Keyword(s):  
Liquid Crystal ◽  
Fast Switching ◽  
Switching Times ◽  
Microwave Applications

scholarly journals Photochromic Organic-Inorganic Hybrid Nanocomposite Hard Coatings With Tailored Fast Switching Properties

1999 ◽  
Vol 576 ◽  
Author(s):  
M. Mennig ◽  
K. Fries ◽  
H. Schmidt
Keyword(s):  
Hard Coatings ◽  
Matrix Composition ◽  
Coating System ◽  
Fast Switching ◽  
Switching Times ◽  
Aromatic Character ◽  
Glass Slides ◽  
The Matrix ◽  
Cross Linker ◽  
Surface Modified

ABSTRACTA recently developed photochromic organic-inorganic nanocomposite (Nanomer®) coating system is investigated, which is based on an epoxysilane as network former, different bisepoxides as spacer and an organic amine as thermal cross-linker. This coating system is compatible with different photochromic dyes like oxazines, pyrans and fulgides and also with surface modified ceramic nanoparticles as filler in order to obtain macroscopic “hard properties” without changing the photochromic kinetics. In order to investigate the dye-spacer interactions and influence on the switching kinetic behavior, the matrix composition was diminished to the network former, the thermal cross-linker and two types (polar and nonpolar) of spacers in different concentrations. Four commercially available spirooxazines with different molecular sizes and polarities were incorporated into the matrices and coatings on glass slides were prepared by float-coating and cured at 130 °C for 2 h. The half darkening and half fading times of the coatings were measured by a fast diode array spectrometer as a function of spacer type and concentration for the four different dyes. The “nonpolar” spacer CHMG did not influence the switching kinetic of the dyes significantly and fast switching times of 2 s - 4 s were obtained. The “polar” spacer PCF (aromatic character) showed interactions with the dye molecules, which led to an increase in the switching times of up to 25 s. The retardation of the switching process increased with increasing spacer content and with increasing polar character of the dye molecule. From these results, it could be concluded that the photochromic behavior of the spirooxazines could be adjusted to different applications by interactions with polar spacers.

A novel red to transmissive electrochromic polymer based on phenanthrocarbazole

RSC Advances ◽  
2016 ◽  
Vol 6 (30) ◽  
pp. 25620-25623 ◽  
Author(s):  
G. Atakan ◽  
G. Gunbas
Keyword(s):  
Optical Contrast ◽  
Fast Switching ◽  
Switching Times ◽  
Electrochromic Polymer

This work describes the synthesis of a novel red to transmissive electrochromic polymer with high optical contrast and fast switching times.

scholarly journals Side-chain engineering of green color electrochromic polymer materials: toward adaptive camouflage application

2016 ◽  
Vol 4 (12) ◽  
pp. 2269-2273 ◽  
Author(s):  
Hongtao Yu ◽  
Shan Shao ◽  
Lijia Yan ◽  
Hong Meng ◽  
Yaowu He ◽  
...  
Keyword(s):  
High Stability ◽  
Strong Absorption ◽  
Polymer Materials ◽  
Side Chain ◽  
Green Color ◽  
Fast Switching ◽  
Switching Times ◽  
Electrochromic Polymers ◽  
Electrochromic Polymer ◽  
Brown Color

The synthesised electrochromic polymers can exhibit a vegetable-green color at lower applied voltages and a soil-brown color in the oxidized-state, excellent solubility, superhydrophobicity, strong absorption, very fast switching times, and high stability.

Iron Loss Characteristics of Motors Fed by Fast Switching GaN-FET Inverters

2020 ◽  
Vol 140 (6) ◽  
pp. 488-494
Author(s):  
Haruo Naitoh ◽  
Takaya Sugimoto ◽  
Keisuke Fujisaki
Keyword(s):  
Iron Loss ◽  
Fast Switching ◽  
Gan Fet
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