Computer tapes

Du Pont called this new lubricant material Krytox (64,65) and initially it had such extraordinary properties that it sold for 200/kg ( 187kg ca 1993). Krytox was and is used ia most of the vacuum pumps and diffusion oil pumps for the microelectronics iadustry ia this country and ia Japan because it produces no hydrocarbon (or fluorocarbon) vapor contamination. It has also found important appHcations ia the lubrication of computer tapes and ia other data processiag appHcations as weU as military and space appHcations. 

The exceUent adhesion to primed films of polyester combined with good dielectric properties and good surface properties makes the vinyhdene chloride copolymers very suitable as binders for iron oxide pigmented coatings for magnetic tapes (168—170). They perform very weU in audio, video, and computer tapes. 

Corrective Action Application Case 1 - Groundwater at the MEMOREX Computer Tape Plant (Santa Clara, California) was contaminated by a leaking underground solvent storage tank (Skladany et al., 1987). Chemical analysis of the groundwater identified the presence of methyl ethyl ketone (MEK) up to 500 ppm xylenes together with ethyl benzene up to 40 ppm cyclohexanone up to 30 ppm cyclohexanol up to 10 ppm acetone up to 10 ppm and toluene, tetrahydrofuran, 2-butanol, and methyl propyl ketone each less than 1 ppm. A biological... 

In addition to the programs to select the optimum discussed previously, graphic approaches are also available and graphic output is provided by a plotter from computer tapes. The output includes plots of a given response as a function of a single variable (Fig. 11) or as a function of all five variables (Fig. 12). The abscissa for both types is produced in experimental units, rather than physical units, so that it extends from—1.547 to + 1.547 (see Table 5). Use of the experimental units allows the superpositioning of the single plots (see Fig. 11) to obtain the composite plots (see Fig. 12). 

Perfluoropolyethers emerged on the market in the early 1970s. The first perfluoropolyether was the homopolymer of hexafluoropropylene oxide produced by DuPont, which has the structure [—CF2CF(CF3)0—] and this new lubricant material was called Krytox.31,32 Krytox was and is used in most of the vacuum pumps and diffusion oil pumps for the microelectronics industry because it does not produce any hydrocarbon or fluorocarbon vapor contamination. It also has important applications in the lubrication of computer tapes and in other data processing as well as military and space applications. 

The inventory of products, isolated intermediates, imports and useful byproducts was initially collected in a complex database with room for additional substances and attributes. For TSCA submission, computer tapes were then easily produced with appropriate plant location grouping and CAS Registry number and inventory number identification. This not only saved considerable clerical effort but assured accuracy in transcription and form preparation. 

Particles with lengths of ca. 0.6 pm are used in computer tapes these account for 25 % of the acicular maghemite that is produced. Other applications of this material include low bias audio cassettes and studio and broadcasting tapes. 

Provides toxicology data for more than 130,000 chemicals in four categories substance identification toxicity/biomedical effects toxicology and carcinogenicity review and exposure standards and regulations. Built and maintained by the National Institute for Occupational Safety and Health (NIOSH) as a segment of the Toxic Release Inventory database. Available online, CD-ROM and computer tape from NIOSH and from commercial database vendors. 

World production of cobalt-free magnetic iron oxides in 1995 was ca. 13 000 t, of which ca. 96% was used in compact cassettes and audio tapes, and ca. 4% in computer tapes. 

Applicants are invited to meet with the FDA before submitting an application to discuss the presentation and format of supporting information. If the applicant and the FDA agree, the applicant may submit tabulations of patient data and case report forms in a form other than hard copy, for example, on microfiche or computer tapes. 

Evidence exists that transients entering computer systems often cause software problems by causing bits to be changed and bits to be added to memory locations. These transients have also been shown to be caused by computer tape recorders providing the inductive impulse. 

After the plate is scanned and the transmittance data are recorded on a magnetic computer tape, the tape is evaluated using an IBM 360 computer. The transmittances are converted to intensities, backgrounds are subtracted, interferences are recognized, and one final answer is chosen from several preliminary answers for each element. Concentrations are obtained from analytical curves prepared prior to sample run and stored in computer memory. 

Producers of magnetic iron oxides include Toda Kogyo and Titan Kogyo (Japan), 3M, Magnox, ISK Magnetics (USA), Saehan Media (South Korea), and Herdilla (India). World production of cobalt-free magnetic iron oxides in 2002 was ca. 10,000 t, of which ca. 96% were used in compact cassettes and audiotapes, and ca. 4% in computer tapes. 

Fig. 5.1 TEM-photographs showing typical morphology of magnetic iron oxide pigments from Toda Kogyo (Table 5.1) Magnification x30000. A) Y-Fe2O3QX-440 ,for computer tapes and studio radio tapes B) Co- Y-Fe2O3TX-3045 ,...

Opaque free flowing aqueous dispersion designed for sizing continuous filament nylon yarns to be woven on water jet looms. Highly efficient product for most difficult fabrics such as computer tapes. 

Computer tapes can be purchased providing information on the physical properties of large numbers of compounds, and immediate access to computer-based information systems via the telephone can be obtained from computer service bureaus. Table 4.7 lists a number of such programs and data bases. 

A computer tape is. .. not unlike an algebraic formula, but this is not an essential limitation, except at the stage when it is being prepared by a human mind. It can be transformed, in the computer, to something much more complex, which is unintelligible to the bare human intellect, and can only be read, so to speak, by another computer. 

So it goes, all day long. The outside of the house is protected with hydrocarbon paint or possibly hydrocarbon derived vinyl plastie siding. In the car the dashboard, steering wheel, carpet, paint, lights, tires, belts, hoses, and in some ears the fenders, are hydrocarbon materials. Hydrocarbon-derived lubricants aid the proper function of the mechanical systems. The desk top at work, the light fixtures, the writing pen, the typewriter case, the computer case, the computer tape, the floppy disk, the hammer handle, the toolbox, and an almost endless stream of materials that make our lives pleasant, easier and more productive, are directly produced from hydrocarbon materials. 

Mass spectrometry data are readily digitized and libraries of mass spectral data for individual substances could be stored on computer tapes. Iflaus Biemann (1926- ), at MIT, had accumulated a library of 8,000 mass... 

Biaxially oriented films of PET polyesters are frequently used in the field of magnetic recording media, such as audio tapes, video tapes, computer tapes, and floppy disks. With the tendency to reduce the size and weight of electric and electronic equipment and to improve their performance, the demands become increasingly exacting. 

The one simulator session they did receive was less than effective, partly because the computer tape provided by Boeing to drive the exercise was not current (another instance of asynchronous evolution). For example, the maps were out of date, and the rules of engagement used were different and much more restrictive than those currently in force in OPC. No Mode I codes were listed. The list of friendly participants in OPC did not include UH-60s (Black Hawks) and so on. The second simulation session was canceled because of a wing exercise. 

Recently, the EPA/OPTS announced the availability of nonconfidential information of the TSCA inventory on a computer tape through NTIS. The inventory is a list of chemicals that are in commercial use in the United States, together with the levels of production. 

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