Concentration, and specific

Loop reactors are particularly suitable as bioreactors to produce, for example, single-cell protein (96). In this process, single yeast or bacteria ceUs feeding on methanol multiply in aqueous culture broths to form high value biomass at 35—40°C, 20 kg/m ceU concentrations, and specific growth rates of... 

The freezing point of the coolant should be monitored for coolants in all types of service. Additionally, maintenance of the corrosion inhibitor levels is requited of the heavy-duty service coolants and the stationary engine coolants. Because corrosion inhibitors and combinations of corrosion inhibitors work most effectively at given concentrations and specific ratios to the other inhibitors, appropriate concentrations must be maintained to maximize corrosion protection. Many manufacturers of coolants for stationary engines, and manufacturers of SCAs, provide an analytical service to monitor the effective inhibitor concentrations in the system periodically. Recommendations can then be made for proper maintenance and inhibitor replenishment. 

The effectiveness is known from experiment for important industrial catalysts and is correlated, in general, in terms of pore characteristics, concentrations, and specific rate equations. 

The role that acid and base catalysts play can be quantitatively studied by kinetic techniques. It is possible to recognize several distinct types of catalysis by acids and bases. The term specie acid catalysis is used when the reaction rate is dependent on the equilibrium for protonation of the reactant. This type of catalysis is independent of the concentration and specific structure of the various proton donors present in solution. Specific acid catalysis is governed by the hydrogen-ion concentration (pH) of the solution. For example, for a series of reactions in an aqueous buffer system, flie rate of flie reaction would be a fimetion of the pH, but not of the concentration or identity of the acidic and basic components of the buffer. The kinetic expression for any such reaction will include a term for hydrogen-ion concentration, [H+]. The term general acid catalysis is used when the nature and concentration of proton donors present in solution affect the reaction rate. The kinetic expression for such a reaction will include a term for each of the potential proton donors that acts as a catalyst. The terms specific base catalysis and general base catalysis apply in the same way to base-catalyzed reactions. 

Dissociation constant, the ratio of the rate of offset of ligand away from a receptor divided by the rate of onset of the ligand approaching the receptor. It has the units of concentration and specifically is the concentration of ligand that occupies 50% of the total number of sites available for ligand binding at equilibrium (see Affinity). 

Figure 1.24 Outlet concentration and specific molar flux of product (PI) in arbitrary units as a function of the space velocity of a feed component.

The procedures discussed so far take as fundamental variables the species concentration and specific rates, the latter obtained from homogeneous experiments. Such procedures are called deterministic—that is, admitting no fluctuation in the number of reactant species—as opposed to stochastic methods where statistical variation is built in. 

Particular advantages of solvent-free methods are enhancement of reactivity, because of the increased concentration, and specific selectivity, because of the restricted mobility. 

The inequality constraints. Various kinds of inequality constraints exist, such as requiring that all of the xiJk yiJc, Qk, Fk, Wk, and so on be positive, that upper and lower bounds be imposed on some of the product stream concentrations, and specification of the minimum recovery factors. A recovery factor for stage k is the ratio... 

Table 3.3 Root mean squared error of concentration and specific thermal power...

Fig. 3.3 Concentrations and specific thermal power computed via model (3.57) with first-order kinetics...

Time-Resolved Laser-Induced Incandescence (by Prof. Alfred Leipertz et al.) introduces an online characterization technique (time-resolved laser-induced incandescence, TIRE-LII) for nano-scaled particles, including measurements of particle size and size distribution, particle mass concentration and specific surface area, with emphasis on carbonaceous particles. Measurements are based on the time-resolved thermal radiation signals from nanoparticles after they have been heated by high-energetic laser pulse up to incandescence or sublimation. The technique has been applied in in situ monitoring soot formation and oxidation in combustion, diesel raw exhaust, carbon black formation, and in metal and metal oxide process control. 

Cell cultures offer many advantages over intact animals when it comes to incorporation of radioactive tracers and studying the effects of drugs or hormones. Thus the tracer or drug may be added and removed at known times, its extracellular concentration and specific activity maintained constant and there is no interference in its metabolism by cells of other organs. This does not mean to say, however, that there are no pitfalls to the use of isotopes in cell cultures. 

From the previous sections it is evident that radionuclides of high specific activity often represent very small amounts (microamounts, non-weighable amounts < 1 pg) of matter, especially if the half-lives are short. Handling of such microamounts requires special precautions, because in the absence of measurable amounts of carriers the radionuclides are microcomponents and their chemical behaviom may be quite different from that observed for macrocomponents. This aspect is of special importance if the system contains liquid/solid, gas/solid or liquid/liquid interfaces. The percentage of radionuclides sorbed on the walls of a container depends on the chemical form (species) of the radionuclide, its concentration and specific activity, and on the properties of the container material. At high specific activity of a radionuclide in solution, the surface of a glass beaker generally offers an excess of surface sorption sites. 

Figure 2. Steady-state relationships between solids retention time, effluent waste concentration, and specific treatment efficiency for completely mixed, continuous flow biological treatment processes...

As described previously, the specific interactions between enzymes and lectins with carbohydrates have been evaluated for use in insulin delivery systems based on responses to chemical and biochemical stimuli. These include pH, changes in specific ion concentration, and specific molecular recognition events [15]. 

Fish allergy with increased IgE total concentrations and specific IgE antibodies against various fish products have been reported in two children with Uver transplants (88). Even though both patients had a personal or familial history of aUery, this again suggested a possible relation between tacrolimus and food allergy. 

In addition to the sample concentration and specific parameters related to the pulse sequence being used, the spectral signal-to-noise ratio (SNR) depends on various components of the spectrometer hardware, in particular the sensitivity of the probe and preamplifier. The SNR can be related to the temperature of the receiver coil ( Tq), its resistance (Rc), the temperature of the sample (Tg), the resistance added to the coil by the sample (i s), and the noise temperature of the amplifier (TA) by the following equation 7... 

Instead of dissolving, hybrid molecules self-organize. Small amounts of these amphiphilic molecules produce surface films larger amounts lead to bulk assemblies, in which clusters of molecules minimize their destructive effect on the network of hydrogen bonds by forming micelles or vesicles (liposomes) with a speciflc topology that depends on the concentration and specific shape of the amphiphilic molecules (see Figure 19.6). 

Laplante and Pottler (1982) observed fluorescence oscillations upon irradiating the 9,10-dimethyl anthracene/chloroform systems continuously. Fluorescence oscillations were found to occur immediately after the reaction was started. However, initial oscillations were usually found to be of horatian nature and periodic oscillations were obtained following a horatian initial period. In some cases the periodic behavior was not reproducible even though the nonperiodic oscillatory behavior could be reproduced. Experiments were carried out to determine the effect of e.g., excitation wavelength, substrate concentration and specificity. The mechanism has not yet been elucidated. 

When the type, concentration and specific surface area of biogenic carbonate is relatively constant within a bed, the range of influence may show little variation, and as the distance between concretions will typically vary between one and two ranges of influence, as explained above, a semi-regular spacing between concretions can arise. Similarly, variations in the type, concentration and/or specific surface area of biogenic carbonate from bed to bed, plus variable bed thicknesses, could cause the range of influence to vary systematically between beds. 

Liquid detergent process patents frequently define both compositional and process requirements, such as raw material concentrations and specifications, order of addition of critical components, thermal history, premix or adjuvant preparation methods, product/process stabilizers, distributive and dispersive mixing requirements, and process instrumentation. These patents apply to the production of primary raw material constituents, such as surfactants, builders, conditioning agents, rheology regulators, hydrotropes, disinfectants, bleach additives, etc., in addition to the specification of fully formulated detergent systems. 

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