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Enamels sealing

At first, the program which investigated the packaging of irradiation-- processed foods, concentrated on the most advanced type of container, the tinplate can. It had performed successfully for a century as a container for thermoprocessed foods. However, as a container for the irradiation-processed foods, its physical, chemical, and protective characteristics had to be evaluated, including the effects of radiation on enamels and end-sealing compounds. This container was satisfactory for packaging foods that were irradiation sterilized while unfrozen (1, 2). [Pg.29]

A screening study for evaluating and selecting components of the tinplate container—tinplate, enamel, end-sealing compound, and side-seam solder—which were irradiated at designated doses and temperatures... [Pg.30]

The three irradiated end-sealing compounds had good adhesion to all the enamels except Enamel 5, the epoxy-wax enamel with aluminum... [Pg.33]

Production Test. In a small-scale production test, tinplate containers with two commercially available enamels and two end-sealing compounds, which were selected from the results of this study, performed satisfactorily when packed with beef and ham. Beef was irradiated with 4.5-5.6 Mrad at 5, —30, and —90°C ham was irradiated with 3-4 Mrad and 6-7.5 Mrad at —30°C. For this production test, beef and ham were packaged in round tinplate containers and ham in Pullman tinplate containers, frozen and refrigerated products were shipped 1,200 miles by truck, and were gamma irradiated at various doses and temperatures. Irradiated products were shipped 1,200 miles in a non-refrigerated truck and stored at selected temperatures and humidities. The integrity of the cans was evaluated after storage for 10 days, 3 months, and 6 months. [Pg.40]

The production test showed that the epoxy phenolic enamel was the preferred enamel for coating tinplate containers used in packaging irradiation-sterilized ham and beef. The preferred end-sealing compound for the same application was the blend of cured and uncured isobutylene-isoprene copolymer. [Pg.40]

The evaluation of the components of the tinplate container showed that the preferred enamel for irradiation processing was the epoxy phenolic the preferred end-sealing compound was the blend of cured and uncured isobutylene—isoprene copolymer. Component testing of tinplate and solder for possible changes in mechanical properties, microstructure, and corrosion resistance indicated that the radiation caused... [Pg.40]

The second analytical method uses a combustion system (O Neil et al. 1994) in place of reaction with BrF,. This method was used for the crocodiles because they were represented by very thin caps of enamel. The enamel was powdered and sieved (20 mg), pretreated in NaOCl to oxidize organic material and then precipitated as silver phosphate. Approximately 10-20 mg of silver phosphate were mixed with powdered graphite in quartz tubes, evacuated and sealed. Combustion at 1,200°C was followed by rapid cooling in water which prevents isotopic fractionation between the CO2 produced and the residual solid in the tube. Analyses of separate aliquots from the same sample typically showed precisions of 0.1%o to 0.4%o with 2 to 4 repetitive analyses even though yields are on the order of 25%. [Pg.127]

Commercial porous ceramic tubes (SCT /US Filter Membralox Tl-70 [7]) were used in this study as support for the zeolite material. They are made (Figure 1) of three consecutive layers of tnacroporous a-Al203 with average pore sizes decreasing from the external to the internal layer. A thin toplayer made of mesoporous y-Al203 was also present in some samples. For gas permeability, gas separation and catalytic measurements the tubes were first sealed at both ends with an enamel layer before zeolite synthesis. Tubes with porous lengths up to 20 cm were used in this study. [Pg.128]

Uses Solvent for natural and synthetic resins, cellulose acetate, nitrocellulose, and some dyes nail polishes dyeing leather sealing moisture-proof cellophane lacquers, varnishes, enamels, wood stains in solvent mixtures perfume fixative jet fuel de-icing additive. [Pg.740]

Reduced to their bare verbal bones, both terms just defined by Pemety prominently appear in one of Duchamp s last ready-mades (MD-196). The immediate function of this minimalist object avant la lettre), inscribed with the artist s monogram M. D., was to serve as a kind of metallic seal set upon the box containing the deluxe edition (32 authorized examples in all) of Robert Lebel s Sur Marcel Duchamp, published the next year to great acclaim. As executed by Duchamp in Paris during the summer of 1958, this is simplicity itself a deep blue, enameled metal (iron) plaque, measuring 15 X 20 cm., which bears an inscription, the kind once familiar to Parisians, neatly laid out in white letters (sans serif). This object, which Jean Clair calls a Ready-made imite, exactly simulates the kind of announcements one formerly saw, a century ago, posted on newly erected apartment buildings. The statement it bears is concise, to say the least ... [Pg.346]

The most common oral condition and dental emergency is dental caries, which is a destructive disease of the hard tissues of the teeth due to bacterial infection with Streptococcus mutans and other bacteria. It is characterized by destruction of enamel and dentine. Dental decay presents as opaque white areas of enamel with grey undertones and in more advanced cases, brownish discoloured cavitations. Dental caries is initially asymptomatic and pain does not occur until the decay impinges on the pulp, and an inflammation develops. Treatment of caries involves removal of the softened and infected hard tissues, sealing of exposed dentines and restoration of the lost tooth structure with porcelain, silver, amalgam, composite plastic, gold etc. [Pg.425]

For the preparation of tubular silica membranes, commercially available mesoporous membranes [17] are used. These tubular supports have a total length of 25 cm and are enamelled at both ends, required for a gas-tight sealing with carbon seals to the reactor, so that an effective porous length of 20 cm remains. The tube consists of 4 layers. Layer 1, 2 and 3 consist of a-alumina with a thickness of 1.5 mm, 40 and 20 im and a pore diameter of 12, 0.9 and 0.2 im respectively. Layer 4 consists of y-alumina with a thickness of 3-4 im a Kelvin radius of 4 nm. A schematic drawing of the cross-section of a mesoporous support tube is provided in Figure 4. [Pg.93]

The tubular supports were measured in a membrane reactor, which could also serve for steamreforming experiments when applicable (Figure 6). The tubes were sealed with carbon sealing at the enamelled ends of the tubes. Permeance measurements were performed at 500°C. [Pg.95]

Not much research was performed on coating of tubes in this project. Results on the coating of commercial tubes show however that it is rather difficult to coat sufficiently defect-free membranes on these supports. As was already stated in chapter 4, the surface roughness of the used tubes was possibly too high to coat high quality silica layers. Another possibility is that here the same problem occurs as was encountered with the sealed flat membranes. Some defects in the membrane layer might result from a bad adherence of the coated layer at the enamel/membrane interface. [Pg.101]

The matching of expansion behavior is of the utmost importance to manufacturers of, for example, multi-layer capacitors, porcelain enameled cast iron sinks, fiber reinforced composites, light bulbs, etc. In all cases, various materials in rigid contact must have their expansion characteristics carefully matched. Inattention to this runs the risk of cracking and shattering of a light bulb at its seal to aluminum, delamination of metallic conductive leads from the ceramic substrate in a hybrid circuit, etc. By changing the composition of a constituent material, its... [Pg.184]


See other pages where Enamels sealing is mentioned: [Pg.359]    [Pg.310]    [Pg.12]    [Pg.512]    [Pg.194]    [Pg.208]    [Pg.493]    [Pg.493]    [Pg.29]    [Pg.30]    [Pg.31]    [Pg.34]    [Pg.93]    [Pg.213]    [Pg.70]    [Pg.92]    [Pg.169]    [Pg.152]    [Pg.357]    [Pg.357]    [Pg.21]    [Pg.183]    [Pg.210]    [Pg.211]    [Pg.512]    [Pg.322]    [Pg.184]    [Pg.753]    [Pg.817]    [Pg.194]    [Pg.208]    [Pg.310]    [Pg.12]    [Pg.261]    [Pg.30]    [Pg.197]   
See also in sourсe #XX -- [ Pg.60 , Pg.184 , Pg.218 ]




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