Simple Equipment

Finally, analytical methods can be compared in terms of their need for equipment, the time required to complete an analysis, and the cost per sample. Methods relying on instrumentation are equipment-intensive and may require significant operator training. For example, the graphite furnace atomic absorption spectroscopic method for determining lead levels in water requires a significant capital investment in the instrument and an experienced operator to obtain reliable results. Other methods, such as titrimetry, require only simple equipment and reagents and can be learned quickly. 

In the spring of 1989, it was announced that electrochemists at the University of Utah had produced a sustained nuclear fusion reaction at room temperature, using simple equipment available in any high school laboratory. The process, referred to as cold fusion, consists of loading deuterium into pieces of palladium metal by electrolysis of heavy water, E)20, thereby developing a sufficiently large density of deuterium nuclei in the metal lattice to cause fusion between these nuclei to occur. These results have proven extremely difficult to confirm (20,21). Neutrons usually have not been detected in cold fusion experiments, so that the D-D fusion reaction familiar to nuclear physicists does not seem to be the explanation for the experimental results, which typically involve the release of heat and sometimes gamma rays. 

These compounds and their derivatives can be manufactured using relatively simple equipment compared to that required for the fatty nitrile derivatives. Cyclization of amidoamines to imidazolines requires higher reaction temperatures and reduced pressures. Prices of imidazolines are therefore high. 

The majority of refineries operated by petroleum companies in different parts of the world to make local products, such as gasoline and burner fuels, also produce jet fuels. Even a small refinery with simple equipment can make suitable jet fuel if it has access to the right cmde. However, the principal supply of both civil and military jet fuels is produced in large refineries. Many are located near major cities and airports and are frequentiy connected by pipeline directiy to the airport. Modem airports have extensive storage and handling faciUties operated by local authorities, petroleum companies or consortia, or the airlines themselves. 

Food Applications. A number of features make en2ymes ideal catalysts for the food industry. They are all natural, efficient, and specific work under mild conditions have a high degree of purity and are available as standardi2ed preparations. Because en2ymatic reactions can be conducted at moderate temperatures and pH values, simple equipment can be used, and only few by-products are formed. Furthermore, en2ymatic reactions are easily controUed and can be stopped when the desired degree of conversion is reached. 

Relatively simple equipment with few maintenance problems... 

The ebonite compound before cure is a rather soft plastic mass which may be extruded, calendered and moulded on the simple equipment of the type that has been in use in the rubber industry for the last century. In the case of extruded and calendered products vulcanisation is carried out in an air or steam pan. There has been a progressive reduction in the cure times for ebonite mixes over the years from 4-5 hours down to 7-8 minutes. This has been brought about by considerable dilution of the reactive rubber and sulphur by inert fillers, by use of accelerators and an increase in cure temperatures up to 170-180°C. The valuable effect of ebonite dust in reducing the exotherm is shown graphically in Figure 30.3. 

The third category, cake filters, although well developed in many wastewater treatment applications, are the least developed of the filtration equipment use by the Biotech Industry. In the organic synthesis laboratory sometimes very simple equipment like a funnel and filter paper is used to accomplish this operation. Some other operations used for this filtration step in the lab are more sophisticated, but many are very labor intensive and limit the capacity of the overall production process itself. As a result, there is a need for optimization of the cake filtration equipment used in biotechnology. Cake filtration equipment is available in batch and continuous modes. Following are several examples of cake filtration units ... 

Relatively simple equipment components Potential for obnoxious and harmful odors... 

SEC is very easy to perform up to the production scale and the results are very reproducible. Because no gradient elution has to be applied, no programmable gradient mixing system is necessary and only comparatively simple equipment is needed for the operation. Additionally, the method can be integrated easily in purification schemes and most of the operational steps can be... 

In the presence of hydrogenation catalysts, certain organic compounds can serve as the hydrogen source. The procedure is useful when hydrogen is unavailable or zoned against only simple equipment is required 18). The... 

The motor manufacturer must be given the torque and Wk of the driven load. If not, he must assume this data and run the chance that the motor may not match the requirements. For simple equipment, such as centrifugal pumps or fans, it is usually sufficient to state the service. 

The method is very effective for the separation of dissolved components and enables the production of high-purity products, in addition to its advantages of being a low-cost and simple method. Liquid—liquid extraction is performed continuously using simple equipment, which can be completely automated and does not require constant labor and service. 

A few simple experiments will be briefly described, the performance of which will provide experience of the technique. Experiment 1 will require the use of an electronic millivoltmeter or of a pH meter which should be used in the millivolt mode this same apparatus can be used for the other experiments. If available, a commercial titrator (or auto-titrator) may be used after experience has been gained with the simple equipment, and apart from Experiment 1, many of the determinations can be performed using a potentiometer. 

Simple equipment. Even a lathe will suffice. 

Simple equipment with provision for wide selection of accurate ratios of carriage-to-mandrel speeds. Powerful machine and many spools of fiber required for large mandrel. 

The experimental data in Figure 3-5 can be obtained in a matter of minutes once the materials are at hand, and they illustrate a quick and useful application of direct absorptiometry with simple equipment. Furthermore, they give an insight into the problem of selecting materials... 

Minerals generally present difficult problems in chemical analysis, and these problems grow more serious when the elements being determined are as difficult to separate as are those named above. The time and effort that x-ray emission spectrography can save are therefore great, but there are obstacles to be surmounted. Among these are (1) Absorption and enhancement effects are often serious. (2) The element of interest may be present at low concentration in a matrix that is unknown and variable. (3) Satisfactory standards are not always easy to obtain. (4) Simple equipment sometimes does not resolve important analytical lines- completely. (5) Sample preparation and particle size often influence the intensities of analytical lines Class II deviations (7.8) can be particularly serious with minerals. 

Advantages Low cost No grinding Broad applicability High b.p. solvent contamination of analyte Low investment Simple equipment Simultaneous extractions in series Low investment Simple equipment Rapid Economic solvent use Good reproducibility Low investment Simple equipment Economical Simple equipment Not traumatic Almost solvent free Concentrated analyte Rapid Low temperatures Rapid Automated Simultaneous extraction Low solvent use Rapid User friendly Automated Sequential extractions Not analyst labour intensive... 

The greatest strength of 2D planar methods is that they distribute components widely over a 2D space of high peak capacity. Multidimensional TLC development has the advantages of requiring simple equipment is compatible with scanning densitometry for solute identification and quantitation and enables exploitation of the spot reconcentration mechanism. 

There are many examples of equipment being sold in areas for which it is not suited. The unsuitability may be a lack of trained operators, a lack of basic knowledge of the equipment s possibilities, equipment inappropriate to the terrain, or, occasionally, equipment so highly specialized that it cannot be adapted to the general use for which it is needed. In general, simple equipment can best be used to demonstrate the value of the use of pesticides. 

The extraction of the common metals from their ores in antiquity was based mainly on relatively simple equipment and processes. Lumps of copper or iron ore, for example, that may have formed part of a ring of stones around an ancient domestic fire and become embedded in its embers, could have been reduced to metal. It is quite reasonable to conjecture, therefore, that some prehistoric campfire became, quite accidentally, the first metallurgical furnace. All that is needed to convert a campfire into a smelting furnace is a small depression in the ground to receive the molten metal. A furnace of this type is illustrated in Figure 42 (Gowland 1912 Killick 2001). 

Low initial investment. Simple equipment, insurance and small dimensions... 

Ferric hydroxide coprecipitation techniques are lengthy, two days being needed for a complete precipitation. To speed up this analysis, Tzeng and Zeitlin [595] studied the applicability of an intrinsically rapid technique, namely adsorption colloid flotation. This separation procedure uses a surfactant-collector-inert gas system, in which a charged surface-inactive species is adsorbed on a hydrophobic colloid collector of opposite charge. The colloid with the adsorbed species is floated to the surface with a suitable surfactant and inert gas, and the foam layer is removed manually for analysis by a methylene blue spectrometric procedure. The advantages of the method include a rapid separation, simple equipment, and excellent recoveries. Tzeng and Zeitlin [595] used the floation unit that was devised by Kim and Zeitlin [517]. 

A dead-stop titration curve is produced if Ag+ is titrated with a halide using a pair of identical silver electrodes. Only whilst both Ag+ and Ag are present will a current flow in the cell, and this is linearly related to the Ag+ concentration. Bi-amperometric titrations require only simple equipment but generally give poorer precision because the currents measured are not necessarily on the limiting current plateau. 

Soil respiration (flush of C02) Field chamber Aerobic incubation for >1 week in lab Indicates soil microbial activity relatively simple equipment conducted in a nonstandard laboratory can be determined in field or in laboratory relatively time-consuming dependent upon organic inputs Parkin et al. (1996)... 

The chlorinolysis of 2,4-dinitrophenyl benzyl sulfide gives a good yield of product which is satisfactory for most purposes without recrystallization. Only simple equipment and inexpensive materials are needed, only 2 or 3 hours of the operator s time are required, and the entire procedure can be completed within 24 homs. 

In most cases, extraction is carried out using simple equipment such as Erlen-meyer flasks or test tubes. A sample, plus the appropriate extractant, is added to the container and shaken for a specified amount of time (see the Procedures in the next sections). A flat top or wrist shaker (see Figure 11.1) is commonly used for Erlenmeyer flasks. In some instances, an end-over-end shaker is required. 

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