Plate heater

Built-Up Mica. When the primary property needed for a particular appHcation is insulation, budt-up mica made by binding layered mica spHttings together serves as a substitute for the more expensive sheet mica. The principal uses for built-up mica are segment plate, molding plate, flexible plate, heater plate, and tape (7). 

Chiron provides a microwell plate heater, a luminometer, and data management software. The plate heater is specially designed to provide precise control of the hybridization temperature (0 0.5°C) and to distribute heat evenly throughout the microwell plate. The luminometer maintains a temperature of 37°C and accommodates the 96-well plates. The data management software runs on an IBM PC or compatible computer with a minimum of 80386,16-Mhz microprocessor, 2 Mb of RAM, monitor, mouse, compatible printer, MS DOS (version 5.0 or greater), and Windows (version 3.1 or greater). 

Figure 2.18 Vapor jet configuration f or boiling on a horizontal flat-plate heater, as postulated by Zuber (1959). Adapted from Leinhard and Dhir, 1973. Reprinted with permission of U.S. Department of Energy.)...

Effect of geometric factors As shown in Section 2.4.3.1, Lienhard and Dhir (1973b) expressed the minimum dimension, L, of a horizontal flat-plate heater in terms of the dimensionless ratio L/ d. For ordinary liquids they found that the CHF is constant as long as L/ d > 3 (Eq. 2-128a). Otherwise, the CHF depends on the actual number of vapor jets (Lienhard and Dhir, 1973b),... 

After samples have been applied to the plate, the plate then needs to be dried. An oven maintained at 25°C or TLC plate heater is then used... 

Yamazaki S and Tsutsumi K. Synthesis of A-type zeolite membrane using a plate heater and its formation mechanism. Micropor Mesopor Mater 2000 37 67-80. 

Layers often require heating after applying the reagent in order to complete the reaction upon which detection is based and ensure optimum color development. Typical conditions are 10-15 min at 105-110°C. If a laboratory oven is used, the plate should be supported on a solid metal tray to help ensure uniform heat distribution. A plate heater (Fig. 2), which contains a 20 X 20-cm flat, evenly heated surface, a grid to facilitate proper positioning of TLC and high-performance TLC plates, programmable temperature between 25°C and... 

Fig. 2 Camag TLC plate heater. (Photograph supplied by D. Jaenchen, Camag, Muttenz, Switzerland.)...

Each heating zone is 20 cm in height, and the power to each zone is controlled by a silicon-controlled rectifier circuit. An additional flat plate heater is located at the bottom of the vessel. Furnace and reactor temperatures are recorded on a 12-point Barber-Colman chart recorder. 

After the chromatography, the back of the plate is dried with a paper towel and immediately placed on a cold plate heater. This is switched on, with a set temperature of 120 °C, until the intensity of the zones reaches a maximnm (ca. 10 min). 

Figure 91. Plate heater with Ceran ceramic heating surface (CAMAG)...

The TLC plate heater must always be operated in an efficient fume cupboard, as the vapors from the reagents must always be assumed to be highly toxic. 

Because of the high rate of heat loss in a fnme cupboard, it is better to set the temperature of the plate heater at 120 °C rather than 100 °C. 

Practical Tip for stabilizing colored zones On their way from the spray cabinet or plate heater to a documentation system, colored chromatograms should be covered with a clean glass plate to minimize reactions with oxygen. 

Reconsider Prob. 1.9. The heat loss will now be eliminated by attaching a flat-plate heater to the cold surface of the wall. The heat transfer coefficient between the heater and the cold ambient is also 10 W/m2 -K. Evaluate the power need in W/m2. Sketch the temperature distribution. 

Also included in Fig. 23 are Bonilla s data (B9a) for nucleate boiling of pentane from a chrome-plated heater, as well as the average over all heat-transfer coefficient, related to the instantaneous overall heat-transfer area, for pentane drops evaporating while rising in water. As noted earlier, the heat-transfer coefficient in the latter case was found to be practically independent of the temperature driving-force in the range studied (up to 15°C). 

SCS method was used to synthesize single phase Ni nanoparticles to display the possibility of transition metal synthesis using SCS. As presented in Fig 1, the precursor materials are dissolved in water and stirred to get a homogeneous solution. This solution is heated over a hot plate heater to initiate the combustion reaction. Once started, the reaction continues in an auto-thermal mode and no further external heating is reqttired, as the energy released dttring exothermic reaction is sufficient to complete the combustion of entire precursors. The products obtained are crystalline and no calcination is reqttired. 

In most cases the derivatization reaction is initiated and/or completed by a heating step, which can be performed in a conventional oven or on a plate heater. For optimum reproducibility modern plate heaters ensure homogenous temperature across their surface and allow precise adjustment over a wide temperature range, typically up to 200°C. 

The solvent used in sample application must be completely removed before the development stage. This step is carried out with or without heating, depending on the volatility of the sample solvent and the volatilities and thermal stabilities of the analytes. Plates are often dried at room temperature in a horizontal position inside fume hood a stream of air or nitrogen may be passed over the layer to hasten evaporation. If heat is required, a hair dryer or other type of blower, laboratory oven, or plate heater (Camag Scientific, Inc., Wilmington, Delaware, U.S.A.) is used. 

Note that the ionization occurs analogously to HPLC-MS and the amounts detected on the plate are comparable to HPLC-MS when using the same MS system. One can start with applications in the range of 1-100 ng/ band. If the standard solution is not available for direct flow injection analysis (FIA) and if information about the capability of ionization and its ionization parameters are not available, higher amounts (500 ng/band) and more tracks are also recommended for application. Typical application volumes were between 2 and 10 pL/ band. Drying of the start zones followed, for example, on a TLC plate heater set at 60°C for 1 min or in a homogeneous stream of warm air. 

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