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Fine definition

Another foil type offered by laminate supphers, reverse-treated foil (RTF), offers an advantage for producing fine lines. The RTF copper has adhesion promoter applied to both sides and is classified by 4562 as code R (reverse-treated bond enhancement [cathode side] stain-proofing on both sides).This approach provides advantages to imaging fine lines. When the copper tooth is reversed, the fabricator can improve fine definition by allowing the etch chemistry process to stop at the surface of the laminate. [Pg.653]

Clays (qv) are aluminosihcate minerals, some of which have definite chemical compositions. In regard to tar sands, however, clay is only a size classification and is usually deterrnined by a sedimentation method. According to the previous definition of fines, the fines fraction equals the sum of the silt and clay fractions. The clay fraction over a wide range of fines contents is a relatively constant 30% of the fines. [Pg.356]

Isobutyhdene diurea [6104-30-9] is a nonhygroscopic white crystalline soHd available in fine (0.5—1.0 mm), coarse (0.7—2.5 mm), and chunk (2.0—3.0 mm) particle sizes. The AAPFCO official definition requires a minimum nitrogen content of 30% with 90% of the nitrogen in water-insoluble form prior to grinding (3). [Pg.133]

In diying solids it is important to distinguish between hygroscopic and nonhygroscopic materials. If a hygroscopic material is maintained in contact with air at constant temperature and humidity until equilibrium is reached, the material will attain a definite moisture content. This moisture is termed the equilibrium moisture content for the specified conditions. Equilibrium moisture may be adsorbed as a surface film or condensed in the fine capillaries of the solid at reduced pressure, and its concentration will vaiy with the temperature and humidity of the surrounding air. However, at low temperatures, e.g., 15 to 50°C, a plot of equilibrium moisture content versus percent relative humidity is essentially independent of temperature. At zero humidity the equilibrium moisture content of all materials is zero. [Pg.1182]

The micas, as a class, are difficult to grind to a fine powder one exception is disintegrated schist, in which the mica occurs in minute flakes. For diy grinmng, hammer mills equipped with an air-transport system are generally used. Maintenance is often high. It has been established that the method of milling has a definite effect on the par-... [Pg.1869]

The definitions coarsely chopped to finely powdered , which formerly in the pharmacopoeias were given as mesh sizes, are mostly nowadays indicated without such a requirement in the DAB 10, V. 4.N6, only coarsely chopped (4000 to 2800 sieve), finely chopped (2000 sieve), and powdered (710 to 180 sieve) are distinguished. The wide particle-size ranges have rightly been criticized [1, 2], partly on the basis of extensive investigations. [Pg.25]

Threshold lamit Value - The term refers to toxicity by inhalation. The abbreviation used is TLV. The TLV is usually expressed in units of parts per million (ppm) - i.e., the parts of vapor (gas) per million parts of contaminated air by volume at 25 °C (77°F) and atmospheric pressure. For chemicals that form a fine mist or dust, the concentration is given in milligrams per cubic meter (mg/m ). The TLV is defined as the concentration of the chemical in air that can be breathed for five consecutive eight-hour workdays (i.e., 40 hours per week) by most people without suffering adverse health effiects. This is the definition given by the American Conference of Governmental Industrial Hygienists. [Pg.443]

Contrary to widespread opinion, the value of Ea is not a constant quantity. As was proved previously [52], the value of E is variable, since it depends on the ordering of macromolecules in the amorphous material of the fiber. At the same time, one can suppose that this ordering will be affected by the specificity of the fine structure of the fiber, and particularly by the type of substructure of the fiber. The relationship determining the modulus Ea appropriate for a definite type of fiber substructure can be derived from Eq. (11) when appropriate values of A are assumed. In the case of the microfibrillar substructure, i.e., for A < I, typical of PET fibers stretched, but not subjected to annealing, this equation has the form [52] ... [Pg.849]

Naturally from the above definition there is some unavoidable overlapping, and a fine strainer of, say, stainless steel cloth is regarded as a filter. There are five main types of filtering units as follows. [Pg.882]

Since the foregoing tests were carried out at -identical conditions of compn and temp, and in a standard test fixture, the burning times serve as a means of checking the relative fineness of thea powdered tungsten fuels. The rapid burning times indicate that both M-10 and M-20 are very fine. Also, the M-10 is definitely finer than M-20, as shown by the difference in burning times... [Pg.523]

A very fine space resolution is required to measure the gradient of turbulent velocity fluctuations and calculate turbulent dissipation directly from the definition [5, 6]. [Pg.333]

Fine-chemical companies have definitely shown interest in micro-reaction technology (see also the commitment in [137]) and have formed their own task forces for this purpose. The increasing number of patents is further proof of the beginning commercial use of micro reactors (see, e.g., [318-321]). [Pg.103]

With foams, one is dealing with a gaseous state or phase of matter in a highly dispersed condition. There is a definite relationship between the practical application of foams and colloidal chemistry. Bancroft (4) states that adopting the very flexible definition that a phase is colloidal when it is sufficiently finely divided, colloid chemistry is the chemistry of bubbles, drops, grains, filaments, and films, because in each of these cases at least one dimension of the phase is very small. This is not a truly scientific classification because a bubble has a film round it, and a film may be considered as made up of coalescing drops or grains. ... [Pg.74]

The reduction of metal hydroxides or oxides powder by polyol was first reported by Figlarz and co-workers, which gave rise to fine powders of Cu, Ni, Co and some noble metals with micrometer sizes (polyol process) [32,33]. The polyol process was first modified for the preparation of PVP-protected bimetallic and monometallic nanoclusters such as Pt/Cu, Pd/Pd, Pt/Co, Pt, Pd, etc. [34-38]. The previous results definitely revealed that Pt, Pd, Cu and Co in these PVP-protected metal or alloy nanoclusters were in a zero-valent metallic state. [Pg.329]

There are no universally accepted definitions of bulk, fine, and specialty chemicals, nor are these classifications based on any intrinsic properties. For example, a substance that is currently viewed as a bulk chemical may well have been classified as a fine chemical at an earlier stage in its development. [Pg.15]

Where is the dividing line between bulk and fine chemicals Here again there is no universally accepted definition. Nonetheless, a useful definition of a fine chemical is one with a price of more than 10 US dollars/kg and a volume of less than 10,000 tons per annum. The latter is rather a large volume for most fine chemicals, e.g. most pharmaceutical intermediates are produced in quantities of less than 100 tons per annum. In practice, the type of technology used is probably more dictated by volume than by product application. [Pg.16]

Hirabayashi (1907) defined Kuroko as an ore which is a fine compact mixture of sphalerite, galena, and barite. This definition can be applied to black ore , but not to yellow ore or siliceous ore because these minerals are not abundant in these ores. Kinoshita (1944) defined Kuroko deposit as a deposit genetically related to the Tertiary volcanic rocks, consisting of a combination of Kuroko (black ore), Oko (yellow ore), Keiko (siliceous ore), and/or Sekkoko (gypsum ore) (Matsukuma and Horikoshi, 1970). The deposit is generally defined as a strata-bound polymetallic sulfide-sulfate deposit genetically related to Miocene bimodal (felsic-basaltic) volcanism (T. Sato, 1974). [Pg.15]


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