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Switching, electronic forming

Polysulphone, Its chemical construction is illustrated in Fig. 1.3. A transparent thermoplastic in its original form. Service temperature of its products is up to about 150 °C. Resistant to hydrolysis (e. g. in repeated heat sterilization). Examples of applications transparent components of medical tools and instruments, electric switches, electronic parts. The industrial polysulphone is poly(ether-sulphone). Trade names Mindel (USA), Udel (USA). [Pg.24]

Fig. 7. A representative pulse power machine used for inertial confinement fusion is the Sandia National Laboratory Particle Beam Fusion Accelerator which consists of a slowly charged primary energy storage Marx capacitor bank under insulating oil, a water dielectric intermediate energy store capacitor, a switched pulse forming line which compresses the waveform in time, and a magnetically insulated transmission line which delivers the power pulse to a vacuum diode to produce energetic electrons or light ions, which are accelerated and focussed by electric and magnetic fields onto a target. Fig. 7. A representative pulse power machine used for inertial confinement fusion is the Sandia National Laboratory Particle Beam Fusion Accelerator which consists of a slowly charged primary energy storage Marx capacitor bank under insulating oil, a water dielectric intermediate energy store capacitor, a switched pulse forming line which compresses the waveform in time, and a magnetically insulated transmission line which delivers the power pulse to a vacuum diode to produce energetic electrons or light ions, which are accelerated and focussed by electric and magnetic fields onto a target.
In this section, we report on the combination of PDMS-based RF electronic devices and pneumatic valves to achieve a pneumatically-switched RF coplanar waveguide. PDMS has stable high frequency dielectric constant and low loss [21], while pneumatic valve technology offers a non-electronic form of control of RF devices eliminating electromagnetic interference and parasitic effects caused by bias lines. The outcomes present opportunities for pneumatically-switched addressable RF devices and elements. These can be utilized to control RF transmission in order to potentially activate or disable RF devices such as antenna and metamaterials [28]. [Pg.216]

Copper and silver are used extensively in the electronics industry because of their excellent electrical conductivity. These metals tend to form a protective surface coating which inhibits further corrosion. When exposed to HjS, a sulfide coating forms, increasing the resistance across contacts on electrical switches (6). [Pg.129]

Conducting Polymers Electronically conducting polymers (such as polypyrrole, polythiophene, and polyaniline) have attracted considerable attention due to their ability to switch reversibly between the positively charged conductive state and a neutral, essentially insulating, form and to incorporate and expel anionic species (from and to the surrounding solution), upon oxidation or reduction ... [Pg.124]

As the second step, the STM tip was locked over the desired particle, feedback was temporally switched off, and voltage-current (V-I) characteristics were measured. The typical trend of the V-I characteristics is shown in Figure 29. Current steps are clearly observable in the presented curve, indicating that the single-electron junction was formed. It is worth mentioning that the characteristics observed in areas without particles demonstrate a normal tunneling behavior (see Fig. 30). [Pg.178]

GP 1] [R 13] So-called micro-strip electrodes (MSE) can act as electrically steerable catalysts when used to switch on and off the conversion of ammonia at moderate voltages, several hundred volts (6 vol.-% NHj, 88 vol.-% O2, balance He 0.51 ms 260-380 °C) [75]. Thereby, NO formation was observed. By emitting and accelerating electrons in the range of mA cm current density from the solid to the gas phase, radicals were formed, typically much more than the number of released electrons, e.g. 10 radicals per electron. This efficient use of energy is referred to as dynamic catalysis. The gas phase near the electrodes contains hot and cold radicals, thus providing a two-temperature system. [Pg.295]

In electrocatalysis, the reactants are in contact with the electrode, and electronic interactions are strong. Therefore, the one-electron approximation is no longer justified at least two spin states on a valence orbital must be considered. Further, the form of the bond Hamiltonian (2.12) is not satisfactory, since it simply switches between two electronic states. This approach becomes impractical with two spin states in one orbital also, it has an ad hoc nature, which is not satisfactory. [Pg.49]

In the bulk form, vanadium oxides display different oxidation states and V—O coordination spheres and exhibit a broad variety of electronic, magnetic, and structural properties [96, 97], which make these materials attractive for many industrial applications. Prominent examples range from the area of catalysis, where V-oxides are used as components of important industrial catalysts for oxidation reactions [98] and environment pollution control [99], to optoelectronics, for the construction of light-induced electrical switching devices [100] and smart thermo-chromic windows. In view of the importance of vanadium oxides in different technological applications, the fabrication of this material in nanostructured form is a particularly attractive goal. [Pg.159]

The dendrimer-type tetranuclear Ru(II)-Os(II)3 complex (22, protonated form) shows an interesting electrochemical behavior due to the presence of free basic sites in its bridging ligands [41]. The protonated form shows a 3-1 oxidation pattern due to the simultaneous oxidation of the three Os-based units, followed by the one-electron oxidation of the Ru-based unit. On addition of base, the six chelating moieties (three on the Ru center and one on each Os center) undergo deprotonation. This causes changes in the oxidation potential of the metal ions, with a consequent switching from 3-1 to 1-3 in the oxidation pattern. [Pg.221]

One of the advances in the field of PET is the design of molecular devices, in which D and A pairs are ingeniously linked by covalent bridges (B) to form D-B-A dyads. Electron transfers between D and A across B in a controlled manner may thus display useful functionalities, such as molecular rectifiers [25], switches [26], biosensors [27], photovoltaic cells [28], and nonlinear optical materials [29]. Spacers that have been utilized are versatile, including small molecules, such as cyclohexane [30], adamantane [31], bicyclo[2.2.2]octane [32], steroids [33], and oligomers of... [Pg.229]


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See also in sourсe #XX -- [ Pg.281 , Pg.282 , Pg.283 ]




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