Computer control trends

The plant components selected should be of proven design supported by strong reference installations. Modem trends are moving towards reduction in manning levels, and the use of central computer control and supervisory systems also ensures maximum efficiency of plant operation. 

It is evident that wet decomposition methods remain a fertile area for development. New digestion techniques need to be designed that address the limitations of the instrumentation and maximize its potential. Development trends for conventional and microwave instmments will focus on sample throughput, enhanced vessel performance specifications, the use of new materials, further refinement of in situ vessel control (direct temperature and pressure, incident and reflected microwave power), and computer-controlled sample digesters with automated capability. 

The current trend in SIM technique is toward computer control of the mass spectrometer with concurrent software development allowing data reduction as peak areas and channel ratios. TTie process of manually distinguishing several ion profiles and of making measurements from an... 

The DLTS method has been well accepted and is used by many laboratories. The trend is to place both the data acquisition and data interpretation under computer control. In addition to making the measurement easier, it allows certain signal processing of the experimental data that simplifies parameter extraction. 

The basic design of the gas chromatograph can be fitted with a range of specific injectors, columns and detectors to optimize the separation of components and aid their identification. Recent developments in computer control, the use of robotic autosamplers and the trend to couple instruments together for sequential procedures have lead to increased automation for routine analytical tasks performed by GCs in research, factory and quality control environments. 

Wittbrodt, J. and W. Erhardt. An inexpensive and versatile computer-controlled PCRmachine using a Peltier element as a thermoelectric heat pump. Trends Genet. 1989, 5(7), 202-203... 

Another trend that is likely to continue is the improvement of traditional techniques and instruments and the discovery of new ones. In the late twentieth century computer-controlled diffractometers came into wide use because they facilitated the collection and processing of digitized diffraction patterns. According to Moore s law, the computing power of integrated circuits doubles about every eighteen months, and, if this law remains valid, the computerization of diffraction technologies should become... 

Second, modem terrestrial industries are following the trend, begun in aviation, of the extensive use of computer control. Hence, hazardous industries must be assiduous about learning from aviation experiences. Already, there have been several major air crashes where the causes of the accidents are at least partly due to issues arising from their computer systems. 

FIA and, in particular, computer-controlled derived techniques still have an important contribution to make to quality control aspects in food analysis. Future trends will accompany the changes observed in analytical laboratories, where mass spectrometry-based detectors are replacing molecular spectrophotometry (e.g., diode array detectors [DAD]). Hence, it is expected the hyphenation of flow injection techniques to mass spectrometry, particularly for sample treatment (extraction, sample matrix removal) using FIA. Other less exploited feature, designated as reversed FIA (Mansour and Danielson, 2012), may also have an important role in future years. In this case, sample is applied as carrier, which allows an enhancement of detection limits. The only constraints are possible sample scarcity or high cost and multiplication of artifacts due to interferences. The future application of FIA is left to the imagination and ingenuity of future food analysts. 

Coarse and fine movements of tip with respect to the surface in the r-direction are required in order to bring the probe into the dynamic range of the gap control loop (the tip approach sequence). The coarse movement may be implemented, as above, with an inchworm and/or lead-screw drive. The trend for modem instruments is to have the approach sequence fully automated and under computer control. 

All modern X-ray fluorescence systems are computer controlled and equipped with automatic sample changers. Different matrix correction models are included in the data evaluation software, and further developments on expert systems will reduce manual calibration work. With WDXRF, the detectability of light elements (down to Be) will be optimized, e.g. by using X-ray tubes and detectors with ultrathin windows and widely spaced (focusing) analyser crystals. In EDXRF, trends are for miniaturization, development and optimization of high-resolution room temperature detectors and extension of the application range towards the determination of light elements. 

A recent trend in particle analysis has been the introduction of personal computer-based automation (3). Sophisticated software packages can be used to automate and speed up the analysis. In some cases these computers can even carry out continuous process control (qv) (see Computer technology). The latest machines also allow the measurements of smaller particles and can detect a wider range of sizes. Machines based on light-scattering principles are being more widely accepted by the industry because of speed. An average analysis takes from 1—2 min, whereas those based on sedimentation principles require from 10—120 min. 

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