Coating components

In pack cementation, the part to be coated is placed in a retort and surrounded with a powdered pack consisting of the coating component and an activator the latter reacts with the coating component to form the carrier vapor, usually a haHde or an inert diluent, to prevent the pack from sintering together and to permit vapor transport of the alloying component through the pack. 

The slurry process requires less coating component. The latter is suspended in a vehicle, eg, lacquer or water, and is painted onto the substrate. The coated part is heated in an alumina retort containing a layer of activator at the bottom. The coating component forms a haHde and is deposited onto and diffused into the substrate. Slurry processes can be either activated or nonactivated. In the latter case, development of the coating reHes purely on diffusion without the possible benefits of vapor deposition. 

Sihcide coatings of refractory metals may contain as much as three to five coating components other than siUcon. A mixture of haUde carriers is selected containing the best carrier for each component. 

Coatomer is the major coat component of COPI vesicles. The Coatomer complex consists of seven different subunits (a -C, COP). 

Biochemical characterization of clathrin-coated vesicles revealed that their major coat components are clathrin and various types of adaptor complexes. Clathrin assembles in triskelions that consist of three heavy chains of approximately 190 kDa and three light chains of 30 40 kDa. Four types of adaptor complexes have been identified to date, AP-1, AP-2, AP-3 and AP-4 (AP for adaptor protein). Whereas AP-1, AP-3 and AP-4 mediate sorting events at the TGN and/or endosomes, AP-2 is involved in endocytosis at the plasma membrane. Each adaptor complex is a hetero-tetrameric protein complex, and the term adaptin was extended to all subunits of these complexes. One complex is composed of two large adaptins (one each of y/a/S/s and [31-4, respectively, 90-130 kDa), one medium adaptin (pi -4, <50 kDa), and one small adaptin (ol-4, <20 kDa). In contrast to AP-1, AP-2 and AP-3, which interact directly with clathrin and are part of the clathrin-coated vesicles, AP-4 seems to be involved in budding of a certain type of non-clathrin-coated vesicles at the TGN. 

A pre-requisite for clathrin-coat assembly is the recruitment to the membrane of an adaptor complex. Similar to what has been observed for the recruitment of coatomer to Golgi membranes, adaptor binding is dependent on the presence of ARF-GTP. However, in contrast to COPI vesicle formation, ARF-GTP is suggested to act in a process before budding and not as a stoichiometric coat component. Other differences between COP-coated and clathrin-coated vesicles concern their uncoating mechanism. Disassembly of clathrin-coated vesicles is believed to depend on the chaperoneHSC 70 and on auxilin. 

Formation of vesicles is likely to require interaction with the soluble coat components of cytoplasmic domains of certain integral membrane proteins that may serve as... 

Boving, H., Hintermann, H., and Hanni, W., Ball Bearings with CVD-TiC Coated Components, / roc. 3rd. Europ. Space Mechanisms and Tribology Symp.,yi2Ldnd, Spain, ESA SP-279 (Dec. 1987)... 

The major surface coat component of Toxocara larvae runs as a set of four closely migrating bands with apparent mobility of 120 kDa on SDS-PAGE. One of these was cloned and sequenced, identified as a serine-rich mucin and designated MUC-1 (Gems and Maizels, 1996). We have now established that there are at least five distinct mucin genes in this parasite, which bear general similarity but important distinctions. Thus, MUC-2, MUC-3, MUC-4 and MUC-5 are all threonine-rich rather than serine-rich, and all five differ in the repeat motifs within the mucin domains. All have similar non-mucin, cysteine-rich domains originally termed NC6 (nematode six-cysteine) domains, and since renamed SXC (six-cysteine), as described below. All mucins have a pair of SXC domains at their C-terminus, while MUC-3 and MUC-5 also have paired N-terminal SXC domains. 

Dynamic coating solution(s) Dynamic coating components do not always need to be added to the BGE, sometimes it suffices to flush in between runs. ... 

Uses. Manufacturing of benzene and other chemicals solvent for pains and coatings component of gasoline... 

Snow, L. D., Doss, R. C. and Carraway, K. L. 1980. Cooperativity of the Concanavalin A inhibition of bovine milk fat globule membrane 5 -nucleotidase. Response to extraction of nucleotidase and of putative cytoplasmic surface coat components. Bio-chim. Biophys. Acta 611, 333-341. 

Starch can be enzymically converted in the presence of pigment. The conversion follows a similar time-temperature cycle as in neat starch conversion. The pigment will adsorb a portion of the enzyme adsorption can be minimized by the addition of sodium silicate to the mixture prior to the addition of the enzyme (Vanderbilt process). Even with silicate treatment, a higher quantity of enzyme will be required to reach a specific viscosity target. Other coating components, such as latex and lubricants, have to be added after the conversion. The Vanderbilt process is now rarely used for the preparation of coating binder. 

Binding agents are the main coating components and principal film formers. Film formation can take place using the following techniques ... 

In all these cases, effective lubrication may be obtained by coating only one of the bearing surfaces, and making use of transfer to create a film on the counterface. Two simple precautions need to be taken to make certain of satisfactory operation. The first is to ensure that the primary surface film on the one coated component is not too heavily burnished before assembly, since it is essential for enough molybdenum disulphide to be present to form two viable films. The second precaution is to run in the system under lightly loaded conditions, so that no surface damage or other fault develops before an effective transfer film is formed on the counterface. 

Place the coated component in a pressure vessel, evacuate to 10 Torr and fill with hydrogen sulphide to 25 - 30 bars, raise the temperature to 195° 5°C and maintain for between 4 and 12 hours. 

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