Rate and efficiency

Dietary adrninistration of ionophores is coupled with the use of anaboHc steroid implants to maximize rate and efficiency of gain in growing catde. Effects of ionophores and anaboHc steroid implants are generally additive. 

Mechanism of Action. The mechanisms by which antibiotic adrninistration at subtherapeutic levels enhance growth rate and efficiency of gain in growing animals have not been clarified. Possible modes of action include disease control, nutrient sparing, and metaboHc effects. There is extensive evidence that the principal benefit from subtherapeutic use of antibiotics results from the control of harmfiil microorganisms. 

Further incentives to use energy-efficient motors are provided by various cost rebate programs offered by utilities based on norsepower rating and efficiency level. Another factor that will have a significant impact is the Energy Policy Act of 1992, in which the U.S. Congress established limits on the lowest level of nominal efficiency that certain classes of motors of standard design can have after 1997. 

When you have pursued source control options and have increased ventilation rates and efficiency to the limits of your expertise, you must decide how important it is to pursue the problem further. If you have made several unsuccessful efforts to control a problem, then it may be advisable to seek outside assistance. The problem is probably fairly complex, and it may occur only intermittendy or cross the borders that divide traditional fields of knowledge. It is even possible that poor indoor air quality is not the actual cause of the complaints. Bringing in a new perspective at this point can be very effective. 

The oxidopicolyl group increases the rate and efficiency of intemucleotide phos-phodiester synthesis. It is cleaved with piperidine. ... 

Over the last several years research groups have also explored the use of microwaves to increase the reaction rate and efficiency of the Biginelli reaction. In one example, polyphosphate ester (PPE) was used as the promoter under microwave conditions to deliver a variety of DHPMs 38 in yields ranging from 65-95% yield with reaction times typically below 2 minutes. ... 

For less polar monomers, the most extensively studied homopolymerizations are vinyl esters (e.g. VAc), acrylate and methacrylate esters and S. Most of these studies have focused wholly on the polymerization kinetics and only a few have examined the mierostructures of the polymers formed. Most of the early rate data in this area should be treated with caution because of the difficulties associated in separating effects of solvent on p, k and initiation rate and efficiency. 

The photoadditions proceed through 1,4-diradical intermediates. Trapping experiments with hydrogen atom donors indicate that the initial bond formation can take place at either the a- or (3-carbon of the enone. The excited enone has its highest nucleophilic character at the (3-carbon. The initial bond formation occurs at the (3-carbon for electron-poor alkenes but at the a-carbon for electron-rich alkenes.191 Selectivity is low for alkenes without strong donor or acceptor substituents.192 The final product ratio also reflects the rate and efficiency of ring closure relative to fragmentation of the biradical.193... 

The bioavailability of drugs from tablets can be markedly influenced by the rate and efficiency of the initial disintegration and dissolution process. Unfortunately, one is faced with a compromise situation — a structure that has both a durable structure prior to administration and the ability to readily break down when placed in the in vivo environment. One of the major factors affecting both these properties is the structure of the tablet, in particular its density (or porosity) and the pore structure. Study of the significance of such measurements and interpretation of the results is a relatively recent field of interest. 

The percent yield calculated in this way corresponds to the amount of product X relative to all products and is not the same as the percent of the starting material converted to X (this latter expression is given by x/a/Co, where C0 is the number of moles of reactant). It should be noted that similar to the relationship between rate and efficiency, a low quantum yield for a photochemical reaction does not necessarily mean that it will be formed in a low yield (the converse is true, however). If, for example, x = 0.005 and 2, t = 0.00005, then... 

Such performance curves are normally determined by the manufacturer from operating data using water at 60°F. Note from Eq. (8-6) that the head is independent of fluid properties, although from Eq. (8-4) the power is proportional to the fluid density (as is the developed pressure). The horsepower curves in Fig. 8-2 indicate the motor horsepower required to pump water at 60° F and must be corrected for density when operating with other fluids and/or at other temperatures. Actually, it is better to use Eq. (8-4) to calculate the required motor horsepower from the values of the head, flow rate, and efficiency at the operating point. The curves on Fig. 8-2 labeled minimum NPSH refer to the cavitation characteristics of the pump, which will be discussed later. 

In conclusion, the rates and efficiencies of hydrogen production by systems directly using photosynthesis fall short of even plausible economic feasibility. Since organic substrates are the ultimate source of hydrogen in photofermentations or indirect biophotolysis processes, it can be argued that it should be simpler and more efficient to extract the hydrogen from substrates using a dark fermentation process, an approach which is discussed next. 

A comparison of the amounts of resin-bound starting material and the product by cleave-and-analyze method might give a clue on the reaction completion. However, uncertainty will arise because (1) the resin-bound starting material and the product are not cleaved at the same rate and efficiency (2) the decomposition may occur during the process and (3) their UV extinction coefficients are different. 

The importance of temperature control of the GPC column cannot be overstated. The use of temperatures above ambient results in lower mobile-phase viscosity, which in turn reduces the back pressure generated by the column. Column life is prolonged, and in some cases higher flow rates may be employed. The reduction in mobile-phase viscosity improves both the rate and efficiency of mass transfer processes, enhancing column performance. While... 

The proportions of the desired 2,6-isomer and the unwanted 2,2-isomer in the alkylated product will vary depending on the rate and efficiency of mixing of the benzyl bromide with the lithium enolate. If the alkylation of the initially formed enolate could be effected without any eiiolatci equilibration, less than 2% of the unwanted 2,2-isom( r would be e. )oct( d. ... 

The efficacy of antibiotics in improving rate and efficiency of growth has been well documented by many researchers. To illustrate the responses in animals, a comprehensive summary involving 937 experiments and more than 20.000 pigs is presented in table 1. Note... 

The In-sltu coal gasification simulator appears to behave much like an underground coal seam undergoing gasification, and yields typical gas at rates and efficiencies very similar to those observed In field tests. At times. It even posed similar control problems, such as locating the combustion face, gas leakage and self re-lgnltlon. 

Indeed, in a study of reaction rate and efficiency as a function of geminal substitution of the VCP, it was found that heteroatom substitution was not required to activate the VCP for intermolecular [5+2] cydoaddition (Tab. 13.14) [51]. Substitution for -H at the 1-position of the cyclopropane with -Me, -TMS, or - Pr led to an acceleration of the reaction that correlated with size of the substituent. Significantly, good to excellent yields and high, if not complete, regioselectivities are observed with a variety of mono-substituted alkynes and simple, unactivated VCPs. 

Commercial sulfur vulcanizations are carried out in the presence of various additives, referred to as accelerators, which greatly increase the rate and efficiency of the process... 

Fluidized-bed combustion systems use a heated bed of sandlike material suspended (fluidized) within a rising column of turbulent air to burn many types and classes of waste fuels. The vendor claims that this technique results in improved combustion efficiency of high moisture content fuels and is adaptable to a variety of waste -type fuels. The scrubbing action of the bed material on the fuel particle is said to enhance the combustion process by stripping away the carbon dioxide and char layers that normally form around the fuel particle. This allows oxygen to reach the combustible material much more readily and increases the rate and efficiency of the combustion process. 

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