Portable Instruments in the Laboratory

UV-Vis spectrometers have become much smaller in recent years due, in part, to the availability of hbre optics and very small grating monochromators. Miniature spectrometers have been available commercially since the 1990s. These spectrometers are often devised so that they can be interfaced to the sample and source via optical fibres. This enables difficult locations to be accessed, analytes of interest to be measured in the field and in-process and biological measurements to be taken. Some of these mini UV-Vis-NIR spectrometers can be nsed both in the laboratory and outside the laboratory for field testing. 

Analytical Instrumentation A Guide to Laboratory, Portable and Miniaturized Instruments G. McMahon 

4 abstration corrected Machined from a solid concave holographic grating aluminium block 

Portable NIR analysers have been used to measure protein, cholesterol and glucose in whole blood and plasma samples in their collection tubes with no sample preparation required  

The MIRAN (miniature IR analyser) series of gas analysers from Thermo Electron Corp. is a versatile gas detection system which allows accurate and fast wavelength 

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Historically, viscosity measurements have been the single most important method to characterize fluids in petroleum-producing applications. Whereas the ability to measure a fluid s resistance to flow has been available in the laboratory for a long time, a need to measure the fluid properties at the well site has prompted the development of more portable and less sophisticated viscosity-measuring devices [1395]. These instruments must be durable and simple enough to be used by persons with a wide range of technical skills. As a result, the Marsh funnel and the Fann concentric cylinder, both variable-speed viscometers, have found wide use. In some instances, the Brookfield viscometer has also been used. 

One of the limitations of the portable field survey instruments in the measurement of americium is that their quantitative accuracy depends on how well the lateral and vertical distribution of americium in the soil compares with the calibration parameters used. These methods can provide a rapid assessment of americium levels on or below surfaces in a particular environment however, laboratory-based analyses of samples procured from these environmental surfaces must be performed in order to ensure accurate quantification of americium (and other radionuclides). This is due, in part, to the strong self absorption of the 59.5 keV gamma-ray by environmental media, such as soil. Consequently, the uncertainty in the depth distribution of americium and the density of the environmental media may contribute to a >30% error in the field survey measurements. Currently, refinements in calibration strategies are being developed to improve both the precision and accuracy (10%) of gamma-ray spectroscopy measurements of americium within contaminated soils (Fong and Alvarez 1997). 

This paper reports on research involved the design, construction, and evaluation of a portable instrument, a "luminoscope", for detecting skin contamination by coal tars via induced fluorescence. The instrument has been used in the laboratory to measure the fluorescence of various coal tars and recycle solvents from liquefaction processes spotted on filter paper on rat and on hamster skin. The practical use of the devices in field test measurements to monitor skin contamination of workers at coal gasifier is discussed. The paper also discusses the practicality and usefulness of the luminescence method for detecting skin contamination. 

One area where LIMSs have not provided out-of-the-box support is in the automation of sample preparation. This may be due to the fact, that analytical labs do not have sample-preparation workstations or that there is no standard for these workstations. Nevertheless, the authors think that sample preparation can be automated, providing similar benehts as in high throughput screening, for example. The use of portable devices such as pocket has been reported in the laboratory [74]. Commercially available applicahons such as LimsLink (Labtronics, Inc.) can upload laboratory instrument data from handheld devices to any LIMS. 

The Fuel Sniffer Sensor The Fuel Sniffer is a portable fuel dilution meter that can be used in the laboratory or in the field to provide rapid measurements of fuel contamination in engine oil. Developed in collaboration with the US navy, the Fuel Sniffer employs a surface acoustic wave (SAW) vapour microsensor to measure the concentration of distillate fuel in used diesel lubricating oil samples. The sensor quantifies the absorbed hydrocarbons by a change in frequency. The instrument samples the head space in the sample bottle and calculates the percent of fuel... 

The drive to reduce the size of conventional instrumentation has come about from a need to take equipment out of the laboratory to the sampling site. This requires an instrument that can be transported easily and that can work in the field, ideally from batteries for at least a few hours. The batteries may be disposable or rechargeable. Some portable devices have the option that they can work from mains electricity consequently, they can also be used back in the laboratory, where they save space due to their smaller footprint and often cost less to run and maintain than their benchtop counterparts. Where equipment may need to be moved from one location to another, even for coupling to another instrument, a smaller footprint and portability is again advantageous. Compact instruments usually require less sample and reagent volumes, which in turn reduces waste. Often, portable equipment is more user-friendly than the benchtop version as it is designed for use by nonscientists as well as scientists. 

Besides EDXRF spectrometers that are intended for use in the laboratory, a number of portable EDXRF instruments are also available. These devices are used in various fields for on-site analysis of works of art, environmental samples, forensic medicine, industrial products and waste materials etc. In their simplest form, the instraments consist of one or more radioisotope sources combined with a scintillation or gas proportional counter. However, combinations of radio-sources with ther-moelectronically cooled soHd-state detectors are also available in compact and lightweight packages (below 1 kg). In Fig. 11.21, schematics of various types of radiosource based EDXRF spectrometers are shown. In Fig. 11.21a, the X-ray source is present in the form of a ring radiation from the ring irradiates the sample from below while the fluorescent radiation is efficiently detected by a solid-state detector positioned at the central axis. Shielding prevents radiation from the source from entering the detector. In Fig. 11.21b and c, the X-ray source has another... 

Several reasons are routinely cited for developing Lab-on-a-Chip devices including reagent savings, use of smaller samples, ease of automation, and reduction of analysis time. Other reasons include the potential for reduction in the size of instrumentation, compatibility with laboratory automation equipment, the ability to provide portable instruments, and the ability to provide point-of-care clinical diagnostics. 

The first IC instruments appeared soon after the first publication about IC in 1977. At present, 16-18 companies produce and sell laboratory equipment for IC totaling a sum of 200 million dollars per year and automatic IC systems for industrial purposes totaling a sum of more than 10 miUion dollars. The wide appH-cation of IC for environmental control, foodstuff and drinks, in medicine, in energetics, in agrochemistry, and other areas is coimected with the appearance of versatile instrumentation in the last few years. Different types of instruments ranging from small, portable, and personal systems to unattended industrial analytical systems have been developed. 

Another type of time-of-flight analyzer which uses a similar type of system to the Galai instrument is known as the Lasentec instrument [49]. This system is portable and has been used for on-line monitoring of particles in a slurry or suspension, as well as for size analysis in the laboratory. The basic system used in the Lasentec instrument is illustrated in Figure 6.15. 

LSH-1000 (Fig. 4) For dispensing cryogenic fluids in the laboratory, there is always a need for a sizable storage vessel which is both portable and efficient. The container shown in Fig. 4 is such a vessel. It has a capacity of 1000 liters and an evaporation rate of about per day. It is mounted on a four-wheeled steerable cart. Controls and instrumentation have been kept to a minimum. The discharge connection is fitted with a vacuum-insulated valve and bayonet-type connection. A iji-in. layer of SI-4 insulation is used for this unit. 

There are two common approaches for measuring americium in the environment. Americium can either be measured directly in the field (in situ) using portable survey instruments or samples can be procured from the field and returned to the laboratory for quantification of americium. 

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