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Scale and ratios

After labelling it is necessary to terminate the reaction by the addition of an amine molecule, such as ethanolamine, and to remove any excess labelling reagent and by-products. (The presence of excess unlabelled antibody is generally not a problem.) Gel filtration, dialysis, and ultrafiltration may be used (see Section 3.2). An antimicrobial agent, e.g. sodium azide, and bovine serum albumin (BSA) are usually added to protect the labelled antibody and prevent losses BSA is also [Pg.239]


Why are time scales and ratios of forces or energies important in studying flow behavior of dispersions ... [Pg.188]

The labelling reactions 238 The monoclonal antibody 239 Scale and ratios 239... [Pg.492]

The polymeric products can be made to vary widely in physical properties through controlled variation in the ratios of monomers employed in thek preparation, cross-linking, and control of molecular weight. They share common quaHties of high resistance to chemical and environmental attack, excellent clarity, and attractive strength properties (see Acrylic ester polymers). In addition to acryHc acid itself, methyl, ethyl, butyl, isobutyl, and 2-ethylhexyl acrylates are manufactured on a large scale and are available in better than 98—99% purity (4). They usually contain 10—200 ppm of hydroquinone monomethyl ether as polymerization inhibitor. [Pg.148]

Flavor Intensity. In most sensory tests, a person is asked to associate a name or a number with his perceptions of a substance he sniffed or tasted. The set from which these names or numbers are chosen is called a scale. The four general types of scales are nominal, ordinal, interval, and ratio (17). Each has different properties and allowable statistics (4,14). The measurement of flavor intensity, unlike the evaluation of quaUty, requires an ordered scale, the simplest of which is an ordinal scale. [Pg.2]

Table 6. Laboratory Unit, Pilot-Plant, and Commercial Scale-Up Ratios... Table 6. Laboratory Unit, Pilot-Plant, and Commercial Scale-Up Ratios...
Peclet number independent of Reynolds number also means that turbulent diffusion or dispersion is directly proportional to the fluid velocity. In general, reactors that are simple in construction, (tubular reactors and adiabatic reactors) approach their ideal condition much better in commercial size then on laboratory scale. On small scale and corresponding low flows, they are handicapped by significant temperature and concentration gradients that are not even well defined. In contrast, recycle reactors and CSTRs come much closer to their ideal state in laboratory sizes than in large equipment. The energy requirement for recycle reaci ors grows with the square of the volume. This limits increases in size or applicable recycle ratios. [Pg.59]

The furnace scales which form on alloy steels are thin, adherent, complex in composition, and more difficult to remove than scale from non-alloy steels. Several mixed acid pickles have been recommended for stainless steel, the type of pickle depending on the composition and thickness of the scale For lightly-scaled stainless steel, a nitric/hydrofluoric acid mixture is suitable, the ratio of the acids being varied to suit the type of scale. An increase in the ratio of hydrofluoric acid to nitric acid increases the whitening effect, but also increases the metal loss. Strict chemical control of this mixture is necessary, since it tends to pit the steel when the acid is nearing exhaustion. For heavy scale, two separate pickles are often used. The first conditions the scale and the second removes it. For example, a sulphuric/hydrochloric mixture is recommended as a scale conditioner on heavily scaled chromium steels, and a nitric/hydrochloric mixture for scale removal. A ferric sulphate/ hydrofluoric acid mixture has advantages over a nitric/hydrofluoric acid mixture in that the loss of metal is reduced and the pickling time is shorter, but strict chemical control of the bath is necessary. [Pg.294]

The power per unit volume is constant. From power consumptions in a bench-scale bioreactor, the necessary agitation rate is calculated for the scale up ratio, using Equation (13.2.1). The choice of criterion is dependent on what type of fermentation process has been studied. The following equation expresses relations for the impeller size and agitation rate in small and large bioreactors. [Pg.288]

All deposits contain various ratios of scale and corrosion products, but often one material predominates, such as calcite or magnetite. These materials have different densities and thermal factors that influence the allowable deposit thickness or weight per unit area before cleaning becomes necessary. Practical allowances usually are between the limitations for each of these two materials. These allowances may be perhaps 50 to 100 mg/cm2 of surface area for lower pressure boilers and 25 to 50 mg/cm2 of surface area for higher pressure boilers. (For a more precise allowance, see the information below.)... [Pg.631]

Cleaning solutions also vary in complexity, depending on the ratios of oil/grease to rust/mill scale and other factors. The most common components include ... [Pg.652]

In the literature a number of different techniques for the preparation of a-sulfo fatty acid esters can be found. There is equipment for small-scale and commercial scale sulfonation. Stirton et al. added liquid sulfur trioxide dropwise to the fatty acids dispersed or dissolved in chloroform, carbon tetrachloride, or tetrachoroethylene [44]. The molar ratio of S03/fatty acid was 1.5-1.7 and the reaction temperature was increased to 65 °C in the Final stage of sulfonation. The yield was 75-85% of the dark colored a-sulfonated acid. The esterification of the acid was carried out with either the a-sulfonic acid alone, in which case the free sulfonic acid served as its own catalyst, or with the monosodium salt and a mineral catalyst. [Pg.468]

Consider a planar premixed flame front, such as that sketched in Figure 5.1.1. For the moment, we will be interested only in long length scales and we will treat the flame as an infinitely thin interface that transforms cold reactive gas, at temperature and density T p, into hot burnt gas at temperature and density T, A.-The flame front propagates at speed Sl into the xmbumt gas. We place ourselves in the reference frame of the front, so cold gas enters the front at speed = Su and because of thermal expansion, the hot gases leave the front at velocity 14 = Sl(Po/a)- The density ratio, Po/Pb, is roughly equal to the... [Pg.68]

In any circumstances, it can be expected that and (5x are algebraic functions of turbulence length scale and kinetic energy, as well as chemical and molecular quantities of the mixture. Of course, it is expedient to determine these in terms of relevant dimensionless quantities. The simplest possible formula, in the case of very fast chemistry, i.e., large Damkohler number Da = (Sl li)/ SiU ) and large Reynolds Re = ( Ij)/ (<5l Sl) and Peclet numbers, i.e., small Karlovitz number Ka = sjRej/Da will be Sj/Sl =f(u / Sl), but other ratios are also quite likely to play a role in the general case. [Pg.141]

The ratio of the Komolgorov length scale and the diameter of the microcarriers correlate with cell damage. Several researchers show that if the ratio falls below one, cell damage increases significantly [34-38]. The size of the smallest... [Pg.129]

Basically, there are four major types of measures that are used in taste intensity measurements (a) threshold measures or estimates of the physical level at which the sensation of sweetness begins, (b) equal-sweetness matches between a sugar and other sweeteners, (c) category or rating scales, and (d) ratio scales. Each method has found its adherents and uses, and each possesses specific advantages and defects that indicate its use for one application, but contraindicate its use for another. These methods and their applications have been critically analyzed and reviewed, " " and it is, therefore, superfluous to deal with the topic here. [Pg.350]

In this expression, w is a typical velocity scale and d a typical length scale, for example the diameter of a micro charmel. The Peclet number represents the ratio of the diffusive and the convective time-scales, i.e. flows with large Peclet numbers are dominated by convection. [Pg.198]

The scale-up ratio is defined as the relationship between productivities of large-scale and small-scale equipment items, i.e. [Pg.225]

Table 32.1 describes 30 persons who have been observed to use one of four available therapeutic compounds for the treatment of one of three possible disorders. The four compounds in this measurement table are the benzodiazepine tranquillizers Clonazepam (C), Diazepam (D), Lorazepam (L) and Triazolam (T). The three disorders are anxiety (A), epilepsy (E) and sleep disturbance (S). In this example, both measurements (compounds and disorders) are defined on nominal scales. Measurements can also be defined on ordinal scales, or on interval and ratio scales in which case they need to be subdivided in discrete and non-overlapping categories. [Pg.161]

Figure 1. Histogram of measurements of molar U/Ca ratio in a number of samples of reef-building corals and one giant clam sample (after Edwards 1988). Also indicated is the U/Ca ratio of seawater. This illustrates the point that corals do not fractionate U from Ca by large amounts when they make their skeletons. U/Ca ratios of corals are similar to values from inorganically precipitated marine aragonite. Mollusks along with most other biogenic minerals exclude uranium. Note that the horizontal axis is on a log scale and that the U/Ca ratio of the clam is almost 5 orders of magnitude lower than that of the corals. This difference is the fundamental reason why there are difficulties with uranium-series dating of mollusks. Figure 1. Histogram of measurements of molar U/Ca ratio in a number of samples of reef-building corals and one giant clam sample (after Edwards 1988). Also indicated is the U/Ca ratio of seawater. This illustrates the point that corals do not fractionate U from Ca by large amounts when they make their skeletons. U/Ca ratios of corals are similar to values from inorganically precipitated marine aragonite. Mollusks along with most other biogenic minerals exclude uranium. Note that the horizontal axis is on a log scale and that the U/Ca ratio of the clam is almost 5 orders of magnitude lower than that of the corals. This difference is the fundamental reason why there are difficulties with uranium-series dating of mollusks.

See other pages where Scale and ratios is mentioned: [Pg.239]    [Pg.239]    [Pg.239]    [Pg.239]    [Pg.86]    [Pg.8]    [Pg.12]    [Pg.297]    [Pg.813]    [Pg.188]    [Pg.321]    [Pg.1071]    [Pg.1118]    [Pg.833]    [Pg.130]    [Pg.22]    [Pg.321]    [Pg.501]    [Pg.62]    [Pg.174]    [Pg.189]    [Pg.235]    [Pg.226]    [Pg.226]    [Pg.226]    [Pg.17]    [Pg.128]    [Pg.118]    [Pg.53]    [Pg.342]    [Pg.295]   


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Scale ratio

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