Portable Instruments in Various Applications

The unique appearance of an infrared spectrum has resulted in the extensive use of infrared spectrometry to characterize such materials as natural products, polymers, detergents, lubricants, fats and resins. It is of particular value to the petroleum and polymer industries, to drug manufacturers and to producers of organic chemicals. Quantitative applications include the quality control of additives in fuel and lubricant blends and to assess the extent of chemical changes in various products due to ageing and use. Non-dispersive infrared analysers are used to monitor gas streams in industrial processes and atmospheric pollution. The instruments are generally portable and robust, consisting only of a radiation source, reference and sample cells and a detector filled with the gas which is to be monitored. 

The widest field of battery application both in the number of batteries and in their diversity is that of portable units and domestic appliances. Typically this involves batteries of low and medium capacity from 0.01 to 100 Ah. Battery-powered electrical units include various radio sets, tape recorders, cell phones, TV sets, audio and video players, radio transmitters for civil and military use, portable flashlights for underground and other use, miniaturized devices electronic watches, hearing aids, pocket calculators, toys, some household appliances (electric shavers, measuring instruments including testers, radiation monitoring instruments, etc.), and various medical devices (cardiac pacemakers). 

As far as applications of on-chip chromatography go, we will most likely see developments geared toward two areas miniature portable analysis systems and highly multiplexed systems. The benefits of miniaturization will enable the creation of detection and diagnostic instruments that are small and easy to use for point of care and military applications. Micro-chromatography devices will also enable development of systems of unprecedented complexity that will allow analysis of highly complex samples with compounds of interest in trace amounts. With such systems, presymptomatic diagnosis of various diseases may become a reality. 

Principles and Characteristics In Chp. 8 of ref. [113a] we discussed elemental analysis modes in which the sample was approached to the elemental analysis tool. Mobile spectrometers are more suitable for in situ or on-line monitoring. Various such tools have recently been developed, as portable XRF and LIES A . X-ray fluorescence (XRF) analysis may be based on either electron or radio-isotope excitation. Compact, rugged, and reliable on-line XRF analysers based on radioisotope excitation have been described [25]. On-line (micro-)XRF analysers need very little if any sample preparation compared to many other techniques. Of prime importance is that the surface at the cell window represents the whole sample stream. The instruments are capable of excellent on-line performance for many applications such as process liquids, slurries, solids (e.g., polymer pellets), powders, and others. Process control XRF allows simultaneous determination of up to 32 elements. 

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