Dedicated instruments

Time, Cost, and Equipment Automated chemical kinetic methods of analysis provide a rapid means for analyzing samples, with throughputs ranging from several hundred to several thousand determinations per hour. The initial start-up costs, however, may be fairly high because an automated analysis requires a dedicated instrument designed to meet the specific needs of the analysis. When handled manually, chemical kinetic methods can be accomplished using equipment and instrumentation routinely available in most laboratories. Sample throughput, however, is much lower than with automated methods. 

Setting out the objectives in a detailed fashion and assigning priority to those objectives is an essential first step and is time well spent. Once carefully considered, it could become clear that the objectives fall into two different categories and that it might be cheaper to purchase two dedicated instruments rather than one large, all-encompassing mass spectrometer. 

Repetitive routine analysis of a specific sample (e.g., for Quality Control) will usually require a dedicated instrument. Therefore, the chromatograph and, in particular, the detector will be chosen for that specific analysis. Consequently, only one detector will be necessary and the purchase of an armory of detectors on the basis that they might be needed in the nebulous future is not advised. An alternative detector can always be obtained if and when the demand arises. The same argument applies to multi-solvent reservoirs and multi-solvent gradient programmers and other accessories that are not immediately required for the specific analysis in mind. 

Abstract Controlled microwave heating has foimd many important applications in the synthesis of heterocycles. Almost all kinds of heterocycles have been prepared (or their preparation attempted) with the aid of microwaves. Many examples of cyclocondensations, reactions where two or more fimctional groups combine with the loss of another small molecule (usually water), have been described. Moreover, microwave irradiation successfully induces cycloaddition reactions, especially in the cases where high temperatures are required. This review collects the most representative examples of the application of microwaves to these two kinds of transformations. Except for a few examples, all the reactions selected have been carried out imder controlled microwave irradiation using dedicated instruments. 

Except for a few examples, all the reactions reported herein have been carried out under controlled microwave heating using dedicated instruments for organic synthesis that register the temperature and pressure of the reaction mixture, giving more reproducible results and allowing to work under safe conditions. 

Surface and interfacial engineering. NSF should expand its support in this area, with emphasis on acquisition by chemical engineers of state-of-the-art instramentation for surface and interface studies. The need for such dedicated instrumentation can be met at a funding level of about 5 milhon per year. 

The committee estimates that, in a given year, somewhere between 10 and 25 of the active groups in surface and interfacial engineering will need to acquire a major instrument for adaptation and use. A funding level of 5 million per year for major dedicated instrumentation can meet most of these needs. 

Aquatec Modular, semi-or fully automatic operation. Microprocessor controlled. A dedicated instrument designed for water analysis, i.e. dedicated method cassettes for phosphate and chloride, 600-100 samples h Flow through spectrophotometer (400-700nm)... 

Other automated systems may be purchased for a specific purpose and are called dedicated instruments, e.g. glucose analyser. Others have fairly restricted applications, an example being the reaction rate analysers which are specifically designed for the kinetic measurements of enzyme activity. Some of the more recently developed instruments employ individual pre-prepared disposable test packs or strip devices which contain all the reagents for each particular assay in a dry form. 

The use of reverse-phase columns with pre-column derivatization of the amino acids offers an acceptable alternative to the dedicated instrumentation of an amino acid analyser or separation by HPLC followed by post-column derivatization. 

Fluorometers designed for research purposes(31) are typically equipped with a xenon arc lamp, monochromators, one or more photomultiplier tubes, cuvet holders, and a computer interface. Some research level fluorometers, such as the Perkin-Elmer LS50, have optional microtiter plate reading accessories with fiber optic bundles. This is convenient since 96-well microtiter plates are commonly used for immunoassay development, and many commercial immunoassays are based on the use of microtiter plates. Fluorometers designed for commercial immunoassay purposes are generally dedicated instruments with few, if any, data acquisition and reduction parameters that can be manipulated by the user. 

In the last ten years several novel theories for the analysis of NMRD profiles have been proposed for different paramagnetic systems. These have resulted in novel equations and computer programs for numerical calculations. In this review we tried to summarize the classical theory as well as some recent theoretical treatments, and to show their applicability to different metal ion systems by selecting some experimental profiles which exhibit the most characteristic features. In the last few years, dedicated instruments, called field-cycling relaxometers, have appeared on the market... 

This type of analysis is conducted with dedicated instruments. It uses chemical reactions that resemble electrochemical detection. The determination can be carried out in two different ways. The first is conducted in a classical way using titration and the second is a coulometric method using a diaphragm cell. The latter is the more sensitive of the two methods, which makes its use compulsory for the determination of very low levels of water (concentrations in the order of mg/1). 

On-line SPE is the most elegant, but at the same time the most difficult enrichment technique to implement. On-line SPE-GC requires a dedicated interface that allows the introduction of the large solvent volume needed for the elution of the SPE cartridge. For on-line SPE-HPLC, which can be performed with simple valve-switching systems as well as with dedicated instrumentation (Figure 13.10), a number of restrictions have to be taken into consideration. 

Supercritical fluid extraction (SFE) utilizes the unique properties of supercritical fluids to facilitate the extraction of organics from solid samples. Analytical scale SFE can be configured to operate on- or off-line. In the online configuration, SFE is coupled directly to an analytical instrument, such as a gas chromatograph, SFC, or high-performance liquid chromatograph. This offers the potential for automation, but the extract is limited to analysis by the dedicated instrument. Off-line SFE, as its name implies, is a stand-alone extraction method independent of the analytical technique to be used. Off-line SFE is more flexible and easier to perform than the online methods. It allows the analyst to focus on the extraction per se, and the extract is available for analysis by different methods. This chapter focuses on off-line SFE. 

Innovative analytical tools and methods have been developed, and dedicated instrumented devices now give access to the necessary reliable data, essential for the optimisation of the process and for the analysis of the potential of the cycle. 

Combinatorial chemistry can produce products that reach the marketplace relatively quickly. Although the drug leads produced by combinatorial chemistry are subject to the same long development times as leads generated by other methods, the technology also delivers products, such as affinity ligands, and the dedicated instrumentation and software that achieve sales immediately. 

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