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Thermal/heat treatments

Figure 9.12 shows boron depth profiles for a B dose of 1015cm 2 at an implantation energy of 0.5 keV and thermal heat treatment at 1,050°C for 10 s. The boron depth profile for 0.5 keV implants is consistent with shallow junction requirements of junction depths of 20 nm. After thermal annealing, the boron profile has spread to depths of 100 nm or more - well beyond the shallow junction... [Pg.122]

Tests were made of V-butt-type welds produced by the MIG process. The nominal composition of the X5039 filler wire and composition of the 5183 filler wire used are also listed in Table II. All welds were made in the flat position using a backup bar, but with no special cooling technique employed. Most of the welds were machine-welded a few were hand-welded. The welds were radiographed and found to be free of obvious defects. All welds were tested in the as-welded condition, i.e., without post-thermal heat treatment, but they had been aged at room temperature for 15 to 30 days. [Pg.113]

I Thermal Heat Treatment Thermo-Chemical Heat Treatment... [Pg.574]

A third model was proposed by Wiesener. In his view, the Co or Fe imis of the adsorbed N4 chelates promoted the decomposition of the chelate upon thermal heat treatment followed by the formation, at high temperature, of CNx, a special form of carbon, bearing nitrogen atoms that would be the tme catalyst [18, 19]. In this scenario, the metal is believed to be only an intermediate and has no role in the electroreduction of oxygen. [Pg.275]

The estabhshment of safe thermal processes for preserving food in hermetically sealed containers depends on the slowest heating volume of the container. Heat-treated foods are called commercially sterile. Small numbers of viable, very heat-resistant thermophylic spores may be present even after heat treatment. Thermophylic spores do not germinate at normal storage temperatures. [Pg.458]

Post-heat treatment of glass induces phase separation and crystalliza tion A very precise secondary heat treatment is necessary to develop and control photochromic properties. Glass-ceramics receive a thermal ceramming process that induces crystallization... [Pg.311]

Vessel heads can be made from explosion-bonded clads, either by conventional cold- or by hot-forming techniques. The latter involves thermal exposure and is equivalent in effect to a heat treatment. The backing metal properties, bond continuity, and bond strength are guaranteed to the same specifications as the composite from which the head is formed. AppHcations such as chemical-process vessels and transition joints represent approximately 90% of the industrial use of explosion cladding. [Pg.150]

Phosphatase Test. The phosphatase [9001-78-9] test is a chemical method for measuring the efficiency of pasteurization. AH raw milk contains phosphatase and the thermal resistance of this enzyme is greater than that of pathogens over the range of time and temperature of heat treatments recognized for proper pasteurization. Phosphatase tests are based on the principle that alkaline phosphatase is able, under proper conditions of temperature and pH, to Hberate phenol [108-95-2] from a disodium phenyl phosphate substrate. The amount of Hberated phenol, which is proportional to the amount of enzyme present, is determined by the reaction of Hberated phenol with 2,6-dichloroquinone chloroimide and colorimetric measurement of the indophenol blue formed. Under-pasteurization as well as contamination of a properly pasteurized product with raw milk can be detected by this test. [Pg.364]

Anhydrous monocalcium phosphate, Ca(H2PObe made in a pan mixer from concentrated phosphoric acid and lime. The high heat of reaction furnishes essentially all the necessary thermal input and subsequent drying is minimized. A small amount of aluminum phosphate or a mixture of sodium and potassium phosphates is added in the form of proprietary stabilizers for coating the particles. Heat treatment converts the coating to a protective polyphosphate (19). [Pg.342]

Direct-current arcs into which no material is introduced have many appHcations as heat sources. Industrial processing of metals using plasma torches has been carried out in the former USSR (126). Thermal plasmas also are used in surface and heat treatment of materials (127,128). Metals can be... [Pg.115]

Process Va.ria.tlons. The conventional techniques for tea manufacture have been replaced in part by newer processing methods adopted for a greater degree of automation and control. These newer methods include withering modification (78), different types of maceration equipment (79), closed systems for fermentation (80), and fluid-bed dryers (81). A thermal process has been described which utilizes decreased time periods for enzymatic reactions but depends on heat treatment at 50—65°C to develop black tea character (82). It is claimed that tannin—protein complex formation is decreased and, therefore, greater tannin extractabiUty is achieved. Tea value is beheved to be increased through use of this process. [Pg.372]

Fabrics composed of synthetic polymer fibers are frequendy subjected to heat-setting operations. Because of the thermoplastic nature of these fibers, eg, polyester, nylon, polyolefins, and triacetate, it is possible to set such fabrics iato desired configurations. These heat treatments iavolve recrystaUization mechanisms at the molecular level, and thus are permanent unless the fabrics are exposed to thermal conditions more severe than those used ia the heat-setting process. [Pg.441]

Extrusion Resins. Extmsion of VDC—VC copolymers is the main fabrication technique for filaments, films, rods, and tubing or pipe, and involves the same concerns for thermal degradation, streamlined flow, and noncatalytic materials of constmction as described for injection-molding resins (84,122). The plastic leaves the extmsion die in a completely amorphous condition and is maintained in this state by quenching in a water bath to about 10°C, thereby inhibiting recrystallization. In this state, the plastic is soft, weak, and pHable. If it is allowed to remain at room temperature, it hardens gradually and recrystallizes partially at a slow rate with a random crystal arrangement. Heat treatment can be used to recrystallize at controlled rates. [Pg.441]


See other pages where Thermal/heat treatments is mentioned: [Pg.497]    [Pg.497]    [Pg.203]    [Pg.300]    [Pg.492]    [Pg.437]    [Pg.335]    [Pg.335]    [Pg.247]    [Pg.308]    [Pg.553]    [Pg.492]    [Pg.497]    [Pg.497]    [Pg.203]    [Pg.300]    [Pg.492]    [Pg.437]    [Pg.335]    [Pg.335]    [Pg.247]    [Pg.308]    [Pg.553]    [Pg.492]    [Pg.289]    [Pg.290]    [Pg.113]    [Pg.130]    [Pg.142]    [Pg.135]    [Pg.149]    [Pg.151]    [Pg.202]    [Pg.237]    [Pg.432]    [Pg.90]    [Pg.443]    [Pg.105]    [Pg.119]    [Pg.121]    [Pg.122]    [Pg.249]    [Pg.344]    [Pg.331]    [Pg.200]    [Pg.497]    [Pg.363]   
See also in sourсe #XX -- [ Pg.319 ]




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