Specific designs

These are analysers conceived for the determination of one analyte or a few in a given type of sample. There are configurations automated to different degrees, with or without a microprocessor, the commonest of which are shown 

Caution should be applied at this point not to confuse this type of analyser with the variety of automatic modules available for sample preparation which offer no analytical information themselves. 

Specific designs have been conceived to resolve special problems in various fields (clinical and metallurgical chemistry, pollution, nutrition, etc.). In fact, they are instruments covered by a denomination referring to the analyte and type of sample for which they are intended. They are particularly suitable for carrying out a more or less large number of crucial determinations in the fields mentioned above. They are characterized by their simple operation (tuning, calibration, sample Introduction, delivery of results) insofar as they are intended for unskilled staff —so much so that few control laboratories know their operational foundation (i.e. the particular determinative technique being applied). 

There are an overwhelming number and variety of commercially available specific designs. As a comprehensive description is beyond the scope of this book, only some significant examples are discussed. Other analysers belonging to this group are commented on the Chapters 14 and 15, devoted to the automatization of clinical and environmental pollution monitoring. 

The CS-244Simultaneous Carbon/Sulfur Determinator manufactured by LECO is a specific microprocessor-controlled analyser developed for the determination of these two elements in metals, ferrous and non-ferrous alloys and various inorganic materials. As can be seen from Fig. 8.12, it consists of three essential elements  

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A new acoustic emission system (AEBIL Acoustic Emission Binary Localizer) meeting the requirements for continuous on-line structural surveillance of critical conponents of operating plants Is described in the paper. The system is specifically designed to identify and locate structurally significant, spatially concentrated, AE sources in the presence of a high rate of spatially diffuse AE events. The system performance and reliability has been extensively demonstrated in In-plant applications. 

NAMD [7] was born of frustration with the maintainability of previous locally developed parallel molecular dynamics codes. The primary goal of being able to hand the program down to the next generation of developers is reflected in the acronym NAMD Not (just) Another Molecular Dynamics code. Specific design requirements for NAMD were to run in parallel on the group s then recently purchased workstation cluster [8] and to use the fast multipole algorithm [9] for efficient full electrostatics evaluation as implemented in DPMTA [10]. 

The family of hierarchical elements are specifically designed to minimize the computational cost of repeated computations in the p-version of the finite element method (Zienkiewicz and Taylor, 1994). Successive approximations based on hierarchical elements utilize the derivations of a lower step to generate the solution for a higher-order approximation. This can significantly reduce the... 

First of all, given the well recognised promoting effects of Lewis-acids and of aqueous solvents on Diels-Alder reactions, we wanted to know if these two effects could be combined. If this would be possible, dramatic improvements of rate and endo-exo selectivity were envisaged Studies on the Diels-Alder reaction of a dienophile, specifically designed for this purpose are described in Chapter 2. It is demonstrated that Lewis-acid catalysis in an aqueous medium is indeed feasible and, as anticipated, can result in impressive enhancements of both rate and endo-exo selectivity. However, the influences of the Lewis-acid catalyst and the aqueous medium are not fully additive. It seems as if water diminishes the catalytic potential of Lewis acids just as coordination of a Lewis acid diminishes the beneficial effects of water. Still, overall, the rate of the catalysed reaction... 

Centralized processing plants specifically designed to handle regional aquaculture crops are estabUshed in areas where production is sufficiently high. In coastal regions, aquacultured animals are often processed in plants that also service capture fisheries. 

Grades of acetal resins specifically designed to enhance the excellent lubricity of the material, without sacrifice in other properties, are known. These include Delrin AF, Ultraform N2311, and Celcon LW materials. Antistatic grades, particularly useful in electronic appHcations, have been developed. At least one recendy introduced new grade, Celcon SR90, claims good scuff resistance. 

Other important properties that can be measured in the laboratory include sealabiHty, printabiHty, or coating adhesion. Many of these tests have been developed by the film manufacturer in cooperation with customers and are specifically designed to measure product performance in the end use. Some tests, like sealabiHty, can be standardi2ed to time, pressure, and temperature of sealing with instmment-measured peel values, but other tests are subjective, such as evaluations of printing loss to puUoff by adhesive tape. 

The specific design most appropriate for biomass, waste combustion, and energy recovery depends on the kiads, amounts, and characteristics of the feed the ultimate energy form desired, eg, heat, steam, electric the relationship of the system to other units ia the plant, iadependent or iategrated whether recycling or co-combustion is practiced the disposal method for residues and environmental factors. 

Although there are several limits which apply to heat pipe operation, these generally lend themselves to specific design solutions or occur at sufficiently high levels of performance to permit a wide latitude of practical appHcations. The envelope of these limits is shown generically in Figure 3. 

Values depend on plant-specific design and operating procedures for steam plant. 

Most CCDs are specifically designed for video camera apphcations, which detect photons in the visible portion of the electromagnetic spectra. 

Fig. 10. The 800 x 800 pixel scientific CCD specifically designed for the Galileo mission to Jupiter. The devices are shown in wafer form after initial...

CCD. Although front-side iEuminated devices are available, the MPP CCD is typically back-side ikuminated in order to achieve state-of-the-art photon collection performance. Even with this stipulation the MPP CCD is still a popular detector due to its availabiUty in various array sizes and formats specifically designed for scientific appHcations. 

Synthetic. The main types of elastomeric polymers commercially available in latex form from emulsion polymerization are butadiene—styrene, butadiene—acrylonitrile, and chloroprene (neoprene). There are also a number of specialty latices that contain polymers that are basically variations of the above polymers, eg, those to which a third monomer has been added to provide a polymer that performs a specific function. The most important of these are products that contain either a basic, eg, vinylpyridine, or an acidic monomer, eg, methacrylic acid. These latices are specifically designed for tire cord solutioning, papercoating, and carpet back-sizing. 

Sugar analysis by hplc has advanced greatly as a result of the development of columns specifically designed for carbohydrate separation. These columns fall into several categories. (/) Aminopropyl-bonded siHca used in reverse-phase mode with acetonitrile—water as the eluent. (2) Ion-moderated cation-exchange resins using water as the eluent. Efficiency of these columns is enhanced at elevated temperature, ca 80—90°C. Calcium is the usual counterion for carbohydrate analysis, but lead, silver, hydrogen, sodium, and potassium are used to confer specific selectivities for mono-, di-, and... 

Standard Test Methods for Steel Tire Cord. ASTM standard D2969-92 includes test methods for steel cords that are specifically designed for use in the reinforcement of pneumatic tires. It describes test methods determining steel cord constmction, break strength, elongation at break. 

After centrifugation, the specimens are placed in a holder specifically designed to work with a particular instmment. Some clinical analyzers utilize... 

Conditions of high pressure and low temperature favor the formation of the complex, whereas low pressure and high temperature tend to release the complexed carbon monoxide from solution. These conditions typify the operation of the absorber-stripper shown in Figure 2. Specific design conditions for the process are given in references 86—88, and an excellent summary of processing considerations is presented in reference 85. 

In the early 1960s the petroleum industry employing molecular sieve technology made available a low cost and plentihil supply of normal paraffin fractions of very high purity. This enabled chlorinated paraffin manufacturers to exploit new appHcations with a range of products specifically designed to meet the technical and commercial requirements. 

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