Interfacing with computers

The Ferranti-Shidey viscometer was the first commercial general-purpose cone—plate viscometer many of the instmments stiU remain in use in the 1990s. Viscosities of 20 to 3 x 10 mPa-s can be measured over a shear rate range of 1.8-18, 000 and at up to 200°C with special ceramic cones. Its features include accurate temperature measurement and good temperature control (thermocouples are embedded in the water-jacketed plate), electrical sensing of cone—plate contact, and a means of adjusting and locking the position of the cone and the plate in such a way that these two just touch. Many of the instmments have been interfaced with computers or microprocessors. 

Instrumentation is rapidly becoming more electronic. However, many users prefer pneumatic, and computer compatibility is available with either although electronic interface with computers is generally preferred. One coal gasification company prefers pneumatic because they feel the inherent corrosive atmosphere around such plants is not kind to electronic equipment. 

Once the best method of dealing with interferences has been decided upon and the most appropriate method of determination chosen, the analysis should be carried out in duplicate and preferably in triplicate. For simple classical determinations the experimental results must be recorded in the analyst s notebook. However, many modern instruments employed in instrumental methods of analysis are interfaced with computers and the analytical results may be displayed on a visual display unit, whilst a printer will provide a printout of the pertinent data which can be used as a permanent record. 

The models where two or four batches of powders can be processed in the cylinders mounted on rotating plate were the workhorse instruments in many laboratories. The recent Pulverisette model 7 was designed with larger rotational speeds specially for processing of powders to nanometric-level size. The Fritsch model Pulverisette mills, models 4, 5, and 6, are compatible with an interesting reactor cylinder, in which the cover is equipped with pressure and temperature sensor and a small radiofrequency unit allows for wireless transfer of the sensors data to the receiver interfaced with computer. This GTP (temperature-pressure) system developed... 

Typically, MR pulse sequences (including radio-frequency and gradient waveforms) are computer generated and computer controlled. The computer also generates eddy-current compensation for the gradients and perhaps other types of compensation for imperfections. Patient tables are typically under computer control. RF receivers interface with computers that convert the raw receiv data into images. Computers typically display and possibly monitor patient comfort and patient safety parameters. Computers typically monitor system hardware as well. 

Computers have been used in laboratories since the mid-1960 s for administrative and managerial support tasks. Recent developments have emphasised the direct interfacing of computers with laboratory instruments and the automatic performance of clerical tasks. In a recent survey of Laboratory Information Management Systems (LIMS) in use in the UK [ISC92], 78% of respondents stated that instruments had been interfaced with computers in their laboratories. A breakdown by analyser and computer type is shown in Table 1. Improvement in laboratory efficiency and saving of staff time were perceived as major benefits. Efficient data retrieval, improved quality control and a greater availability of information for administrative and management purposes are major facilities provided by LIMS. 

Modem tensiometers are interfaced with computers to increase the accuracy of the measurement and obtain dynamic surface tension readings within short but accurately measured time intervals. 

In modem microwave reactors, digital thermometers (sensors and probes) are itsed for temperature control. Moreover, some sophisticated ovens even interface with computers for reaction monitoring (Barlow and Marder, 2003 Raner et al., 1995). 

Another important compatibility, of course, is with the search and retrieval software of the online system. This can mean both a public and a corporate system serving the same user. Similarly, the user may wish to interface with computation support software, which may be operated on both public and corporate systems. 

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