Sandwich heating

Sandwich heating (two-sided heating) n. A method of heating a plastic sheet for thermoforming in which the sheet is positioned between two radiant heaters. 

Each member of the N-Lite Series (National Starch) is aimed at a specific role ia fat replacemeat, ie, N-Lite L for soups and sandwich spreads N-Lite LP for use ia dressiags and dips. N-Lite LP is an iastant modified food starch which yields a very oily texture and is stable to heat, acid, and shear N-Oil is a tapioca dextria suggested for fat-like mouthfeel and the N-Elate and N-Oil Series are propriety mixtures of starches and other fat replacers. 

Many polymers, including polyethylene, polypropylene, and nylons, do not dissolve in suitable casting solvents. In the laboratory, membranes can be made from such polymers by melt pressing, in which the polymer is sandwiched at high pressure between two heated plates. A pressure of 13.8—34.5 MPa (2000—5000 psi) is appHed for 0.5 to 5 minutes, at a plate temperature just above the melting point of the polymer. Melt forming is commonly used to make dense films for packaging appHcations, either by extmsion as a sheet from a die or as blown film. 

Several compounds such as BaZrS [12026-44-7], SrZrS [12143-75-8], and CaZrS [59087-48-8], have been made by reacting carbon disulfide with the corresponding zirconate at high temperature (141), whereas PbZrS [12510-11-1] was produced from the elements zirconium and sulfur plus lead sulfide sealed in a platinum capsule which was then pressurized and heated (142). Lithium zirconium disulfide [55964-34-6], LiZrS2, was also synthesized. Zirconium disulfide forms organometaUic intercalations with a series of low ionization (<6.2 eV)-sandwich compounds with parallel rings (143). 

Golorfastness to Heat Treatment. To test for fastness to dry heat, ISO 105-P01 the specimen is sandwiched between adjacent fabrics and placed under slight pressure between heated surfaces where the temperature of the surface is 150, 180, or 210°C for 30 s. The effect on the shade of the pattern and adjacents is then assessed. 

Honeycomb core. Honeycomb core used for aluminum bonded sandwich structure is exclusively aluminum. The core is fabricated by printing offset stripes of adhesive (the node adhesive) on aluminum foil, stacking a large number of these foils and then curing the adhesive in a heated press. The resulting block is called a hobe. Slices are machined from the edge of the hobe and then expanded to... 

This type of filter allows pressurized filtration of a slurry mixture to remove solids. A set of filter plates is sandwiched together in series with a configuration similar to the plates on a plate-and-frame heat exchanger. After the plates are compressed... 

A variation of thermoforming which does not involve gas pressure or vacuum is matched die forming. The concept is very simple and is illustrated in Fig. 4.53. The plastic sheet is heated as described previously and is then sandwiched between two halves of a mould. Very precise detail can be reproduced using this thermoforming method but the moulds need to be more robust than for the more conventional process involving gas pressure or vacuum. 

Valepotriates are detected by placing the chromatogram 0.3 mm from a TLC plate sprayed with cone, ammonia solution (sandwich configuration layer to layer), fastening with clips and heating to 110°C in a drying cupboard for 10 min [12]. 

Rubber blends with cure rate mismatch is a burning issue for elastomer sandwich products. For example, in a conveyor belt composite structure there is always a combination of two to three special purpose rubbers and, depending on the rubber composition, the curatives are different. Hence, those composite rubber formulations need special processing and formulation to avoid a gross dissimilarity in their cure rate. Recent research in this area indicated that the modification of one or more rubbers with the same cure sites would be a possible solution. Thus, chlorosulfonated polyethylene (CSP) rubber was modified in laboratory scale with 10 wt% of 93% active meta-phenylene bismaleimide (BMI) and 0.5 wt% of dimethyl-di-(/ r/-butyl-peroxy) hexane (catalyst). Mixing was carried out in an oil heated Banbury-type mixer at 150-160°C. The addition of a catalyst was very critical. After 2 min high-shear dispersive melt mix-... 

To investigate corrosion in heated crevices filled with wetted paste a sandwich test assembly was designed by Gleekman and Swandby simulating... 

Forming requires thorough, fast, and uniform radiant heat from the surface to the core to the surface of the sheet or film. As a general guide, to achieve these conditions, sheet plastics over 0.040 in. (1.02 mm) should use sandwich-type (under and over the sheet) heater banks. To ensure that sufficient heat... 

This low pressure process, also known as elastic reservoir molding, consists of making basically a sandwich of plastic-impregnated open-celled flexible polyurethane foam between the face layers of fibrous reinforcements. When this plastic composite is placed in a mold and squeezed, the foam is compressed, forcing the plastic outward and into the reinforcement. The elastic foam exerts sufficient pressure to force the plastic-impregnated reinforcement into contact with the heated mold surface. Other plastics are used. 

When modified fibres of type 5 are treated with hydroxylamine, oxime groups are also easily formed. The interaction with a protein affords a sandwich polymer22. Fibres modified in this way have enhances dyeability. When copolymer fibres are treated with diamine solutions or in acid medium with Fe+3 salts, intermolecular chemical bonds are formed, which results in a considerable increase of the temperature of zero strength and of the heat resistance of fibres. These conversions are shown in Scheme 2. 

The cemented lap seam used in these cans is a sandwich of plate, organic coatings, and cement. The body is formed on a modified body-maker, and the process is based on the control of heat input and removal. Welded cans are also made on a modified bodymaker. Coated TFS body blanks with bare edges are fed into the bodymaker where the margins are cleaned so that a uniform electrical resistance will be presented to the electric current provided to weld the side seam. 

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