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Minor variation

It was observed very early that rather minor variations in the composition of the oils could make great differences in performance and many secret recipes developed. The field is unusual in that empirical practice has been in the lead, with theory stmggling to explain. Some basic aspects are fairly well under-... [Pg.472]

Synthesis This was in fact done by a minor variation on our strategy, the ethyl group being added later ... [Pg.122]

Reaction 1 is highly exothermic. The heat of reaction at 25°C and 101.3 kPa (1 atm) is ia the range of 159 kj/mol (38 kcal/mol) of soHd carbamate (9). The excess heat must be removed from the reaction. The rate and the equilibrium of reaction 1 depend gready upon pressure and temperature, because large volume changes take place. This reaction may only occur at a pressure that is below the pressure of ammonium carbamate at which dissociation begias or, conversely, the operating pressure of the reactor must be maintained above the vapor pressure of ammonium carbamate. Reaction 2 is endothermic by ca 31.4 kJ / mol (7.5 kcal/mol) of urea formed. It takes place mainly ia the Hquid phase the rate ia the soHd phase is much slower with minor variations ia volume. [Pg.299]

Propionic acid made in butane LPO probably comes by a minor variation of reaction 38 that produces methyl radicals and propionaldehyde. It is estimated that up to 18% of the j -butoxy radicals may decompose in this manner (213) this may be high since propionic acid is a minor product. [Pg.343]

Scale control can be achieved through operation of the cooling system at subsaturated conditions or through the use of chemical additives. The most direct method of inhibiting formation of scale deposits is operation at subsaturation conditions, where scale-forming salts are soluble. For some salts, it is sufficient to operate at low cycles of concentration and/or control pH. However, in most cases, high blowdown rates and low pH are required so that solubihties are not exceeded at the heat transfer surface. In addition, it is necessary to maintain precise control of pH and concentration cycles. Minor variations in water chemistry or heat load can result in scaling (Fig. 12). [Pg.270]

The catalysts for these compounds are based on aluminum (Nippon Zeon) or tin (Daiso) (12,13). The preferred catalysts are triaLkylalurninum—water combinations used with or without a chelating agent such as acetylacetone. Except for minor variations, few changes in catalyst composition have been made since it was first formulated. [Pg.553]

However, due to the minor variations in the phase impedances, all the phases may not be subjected to identical severity of faults. For instance, in the above test each phase has recorded a different fault cunent. To evaluate the fault level from these test data, the general practice has been to consider the phase that has recorded the highest fault current as the base, which may occur in any of the phases. In the above test, it has occurred in phase Y. For this fault current, the test duration is adjusted to achieve the required severity of fault in terms of thermal effect (50 x 1 in the above case). [Pg.433]

Rearrangements are also observed during halojluonnanons with cyclic medium ring dienes [70, 93] (equations 4 and 5) and with the monoepoxide of 1,5-cyclooctadiene [94] (equation 6) during halofluonnations Again, there are differences in product mixture with apparently minor variations in reagents (equation 4)... [Pg.63]

The above scheme to account for products of nitrile hydrogenation was proposed sixty years ago (80), and with minor variations 28,45,86] has withstood the test of time, It might be expected from the foregoing that, if a nitrile were reduced in the presence of an amine, unsymmetrical amines would result 48), and indeed the reaction provides an excellent way of preparing these amines 49,74). [Pg.95]

Several Intermetallics, for example Ni3Al, are ordered right up to the melting temperature showing only minor variation of order parameter with temperature. In the present paper LRO-kinetics is studied in CusAu, where a Ti of about 390°C allows a considerable variation of the degree of LRO until its complete dissolution. We report on results of recrystallized material as well as samples deformed in the disordered and the ordered state. Part of this work was already presented at an earlier conference. ... [Pg.207]

Most steels fall into this category, ranging from large structural sections to thin sheet, and minor variations in composition do not markedly affect their corrosion resistance. This is not generally important since such steels are usually protected by some form of coating which is specific for the condition of service. [Pg.45]

The available range of plastics is very wide with a variety of compositions and related properties within any one type description. Even when physical properties and formulation are specified, minor variations in trace additives, release agents, moulding cycles, etc. may have a considerable influence on corrosivity. Table 18.18 can therefore be considered only as a guide and even in this sense much more experimentation is needed to provide the full picture. In the present state of technology precise information is only likely to result from tests carried out on the material of interest various suitable test methods have been described in the literature ... [Pg.951]

The same argument implies that the analytic continuation of q x) in the unit circle is meromorphic. The argument is based on the functional equation (4.16) which is equivalent with the continued fraction (8 ). The continuation of q x) is derived from the continuous fraction by a minor variation of the reasoning used above. We note the following shortcut. [Pg.79]

This test has possible advantages over the notched Izod test. The notch sensitivity factor is eliminated, and energy is not used in pushing aside the broken portion of the specimen. The test results are recorded in ft-lb/in.2 (kJ/m2). This allows for minor variations in dimensions of the minimum in cross-section area. [Pg.312]

Reactions between carbon-centered radicals generally give a mixture of disproportionation and combination. Much effort has been put into establishing the relative importance of these processes. The ratio of disproportionation to combination (kt /k]t ) is dependent on the structural features of the radicals involved and generally shows only minor variation with solvent, pressure, temperature, etc. [Pg.39]

Pre-boiler pretreatment is concerned with providing higher quality MU and FW—that is, water with most, if not almost all, natural impurities removed. There are perhaps as many interpretations of what constitutes high-quality water as there are boiler designs requiring it, and consequently there are also many specifications available, each with minor variations on a similar theme. Trying to decide precisely what is required, above and beyond a basic good quality, as provided by the use of pretreatment equipment such as filters, softeners, and so forth is difficult. [Pg.341]

As far as dialkyl sulfosuccinates are concerned, there are minor variation possibilities known from the market products. Most of the substances available are dialkyl sulfosuccinates. The variation is limited to the fatty chain. Either linear, branched, or cyclic aliphatic groups are used. No ethoxylated sulfosuccinate diesters could be recognized. [Pg.509]

The key features of the EHI system are the monochromators and PUT assembly, since the former allow for minor variations In excitation or emission wavelength that may be necessary to differentiate lumophores of closely related structure, and the latter provides a means of quantitating luminescent species under study. Each monochromator has a resolution capability of 1 nm, and we anticipate that by careful selection of excitation and... [Pg.87]

This procedure, with minor variations, is repeated dozens of times in the manufacture of a semiconductor chip. The chemical treatment can be carried out using reagents in a liquid phase, but gas-phase treatment by a process known as chemical vapor deposition (CVD) has become more important as individual features in the integrated circuit become smaller. [Pg.425]


See other pages where Minor variation is mentioned: [Pg.220]    [Pg.92]    [Pg.71]    [Pg.17]    [Pg.211]    [Pg.8]    [Pg.1815]    [Pg.1962]    [Pg.336]    [Pg.214]    [Pg.618]    [Pg.116]    [Pg.46]    [Pg.1220]    [Pg.15]    [Pg.163]    [Pg.570]    [Pg.35]    [Pg.79]    [Pg.26]    [Pg.302]    [Pg.154]    [Pg.155]    [Pg.156]    [Pg.156]    [Pg.430]    [Pg.37]    [Pg.656]    [Pg.110]    [Pg.259]   
See also in sourсe #XX -- [ Pg.156 ]




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