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Micro-radiation

In this case, the wall thermal resistance is considered negligible. This kind of thermal boundary condition can be used, for example, for micro-radiators working in space and manufactured with materials having a large value of thermal conductivity. [Pg.494]

Micro-radiators in space power systems with negligible normal wall resistance... [Pg.495]

For the development of design surface, a distinction between the pre-and posttreatment of mold cavity surface and pure pre-treatment for coating (e.g., eroded mold surfaces) has to be done. For the design development, processes such as micro-radiation, mat-down treatment, or micro mat can be used. Depending on the technology used, as shown in Figure 2.110, paint-like or very dull surfaces can be established. [Pg.432]

Notice from this equation that energy is inversely related to wavelength. This explains why you put on sunscreen to protect yourself from UV solar radiation (<400 nm) and a lead apron when dental x-rays (<10 nm) are being taken. Conversely, IR (>700 nm) and micro-wave photons (>80,000 nm) are of relatively low energy (but don t try walking on hot coals). [Pg.135]

Infrared (IR) thermography is one of the most advanced non-destructive (NDT) methods based on the fact that all bodies whose absolute temperature is above zero emit electromagnetic radiation over a wide spectrum of wavelengths depending on the temperature. Recently, several researchers have applied it to micro-scale temperature measurement. Hetsroni et al. (2001a) constructed a thermal micro-system... [Pg.28]

In Proceedings of 21st SemiTherm Symposium, San Jose, 15-17 March 2005, pp 354—360 Mohr J, Ehrfeld W, Munchmeyer D (1988) Requirements on resist layers in deep-etch synchrotron radiation lithography. J Vac Sci Technol B6 2264-2267 Morini GL (2004) Single phase convective heat transfer in micro-channels overview of experimental results. Int J Thermal Sci 43 631-651... [Pg.96]

Specific surface areas of the catalysts used were determined by nitrogen adsorption (77.4 K) employing BET method via Sorptomatic 1900 (Carlo-Erba). X-ray difiraction (XRD) patterns of powdered catalysts were carried out on a Siemens D500 (0 / 20) dififactometer with Cu K monochromatic radiation. For the temperature-programmed desorption (TPD) experiments the catalyst (0.3 g) was pre-treated at diflferent temperatures (100-700 °C) under helium flow (5-20 Nml min ) in a micro-catalytic tubular reactor for 3 hours. The treated sample was exposed to methanol vapor (0.01-0.10 kPa) for 2 hours at 260 °C. The system was cooled at room temperature under helium for 30 minutes and then heated at the rate of 4 °C min . Effluents were continuously analyzed using a quadruple mass spectrometer (type QMG420, Balzers AG). [Pg.173]

This is also (see [R 6]) a commercial chip ( Radiator ), provided by MCS, Micro Chemical Systems Ltd., The Deep Business Center [20]. A bottom plate contains an extensively wound serpentine channel. A top plate covers this microstructure. The two reactant solutions enter via capillary tubing through holes in the top plate. The first reactant is fed at the start of the serpentine path and the second enters this path in a short distance. Shortly before the end of the serpentine, a third stream can enter which may serve, e.g., for dilution and thus quenching of the reaction. After a very short passage, the diluted streams enter via a fourth port analytics. Commercially available capillary connectors were employed. [Pg.387]

International Union of Pure and Applied Chemistry International Union of Pure and Applied Physics Laser (Ablation) Micro Mass Spectrometry Light Amplification by Stimulated Emission of Radiation Liquid Chromatography... [Pg.25]

EPR spectrometers use radiation in the giga-hertz range (GHz is 109 Hz), and the most common type of spectrometer operates with radiation in the X-band of micro-waves (i.e., a frequency of circa 9-10 GHz). For a resonance frequency of 9.500 GHz (9500 MHz), and a g-value of 2.00232, the resonance field is 0.338987 tesla. The value ge = 2.00232 is a theoretical one calculated for a free unpaired electron in vacuo. Although this esoteric entity may perhaps not strike us as being of high (bio) chemical relevance, it is in fact the reference system of EPR spectroscopy, and thus of comparable importance as the chemical-shift position of the II line of tetra-methylsilane in NMR spectroscopy, or the reduction potential of the normal hydrogen electrode in electrochemistry. [Pg.11]

Silver halide fibres (AgClxBri x) have the widest spectral range in the mid-IR, well into the fingerprint range. Due to their crystalline nature, they have a superior flexibility. Problematic is their tendency to decompose upon contact with UV radiation or base metals. Also sulphides will chemically destroy the fibre material. Other points against are the high intrinsic attenuation due to absorption by impurities or scattering at inclusions or micro-crystals and the non-availability of (applicable) core-clad fibres. [Pg.139]

As a further consequence of these assumptions, it might be foreseen that micro-wave effects could be important in determining the selectivity of some reactions. When competitive reactions are involved, the GS is common for both processes. The mechanism occurring via the more polar TS could, therefore, be favored under the action of microwave radiation (Scheme 3.7). [Pg.75]

Similarly, in the cycloaddition of cydopentadiene (23) with methyl acrylate (34), described by Gedye, microwave radiation does not alter the endo/exo selectivity and the observed changes can be explained on the basis of the reactions under micro-wave conditions occurring at higher temperatures than those occurring under reflux and under pressure (Scheme 9.8) [49]. [Pg.303]

There have also been attempts to affect photochemical reactions by use of other sources of nonclassical activation, for example ultrasound [20, 21], Combined chemical activation by use of two different types of electromagnetic radiation, microwave (MW) and ultraviolet (UV)/visible (VIS), is covered by the field broadly called micro-wave photochemistry. The energy of MW radiation is considerably lower than that of... [Pg.463]

Milnes and Mostaghaci [5.5] compared the consequences of different drying methods on the density, the sinter rate and micro structures of sublimated TiO-, suspensions. Evaporation of water in a micro-oven and by radiation heating leds to strongly bound agglomerates, while freeze drying resulted in softly bound secondary clusters. The freeze dried powder reached in 2 h of sintering 98 % of the theoretical density, while differently dried powders needed twice as much time and had a less fine microstructure. [Pg.250]


See other pages where Micro-radiation is mentioned: [Pg.151]    [Pg.187]    [Pg.45]    [Pg.344]    [Pg.456]    [Pg.90]    [Pg.425]    [Pg.702]    [Pg.209]    [Pg.147]    [Pg.452]    [Pg.29]    [Pg.29]    [Pg.90]    [Pg.865]    [Pg.111]    [Pg.634]    [Pg.528]    [Pg.550]    [Pg.517]    [Pg.20]    [Pg.301]    [Pg.477]    [Pg.68]    [Pg.46]    [Pg.31]    [Pg.283]    [Pg.341]    [Pg.337]    [Pg.338]    [Pg.343]    [Pg.52]   
See also in sourсe #XX -- [ Pg.407 ]




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