Real-time processing

Obtain real-time process data confirm process models... 

Implement sustainable real-time process control strategies... 

Monitor pollution in real time. Processes should be monitored in real time for the formation of hazardous substances. 

Process automation implies the real time acquisition and control of process variables such as temperature, agitation, material delivery, or quality control measurements. As far as the MARS system is concerned, a real time process is just like any instrument. The acquisition module merely requires more interactive monitoring, alarms, and control. This can be accomplished by means of a real time multi-tasking data acquisition module. 

The batch process control system we ve purchased provides only a starting point for our process research lab we must also identify and test a comprehensive set of controlled devices and real-time process instruments for chemists and engineers to use as building blocks for real feedback control systems. The technologies we are evaluating for characterization of polymer batches at all process stages include ... 

In petrochemical and bulk commodity chemical manufacture, real-time process control has been a fact of life for many years. There is considerable understanding of processes and control of process parameters is usually maintained within tight specifications to ensure statistical process control to within six sigma, or the occurrence of one defect in a million. This has been enabled through the use of real-time analytical capability that works with programmable logic circuits to make small changes to various process inputs and physical parameters as required. 

In batch chemical operations, this level of real-time process control is rarely achieved, although there are increasing attempts in recent years to achieve greater statistical process control, the industry is generally only able to operate at about three or occasionally four sigma, or one defect in 1000-10 000. 

Biosensors may provide the basis for in-field analyses and real-time process analysis. However, biosensors are generally limited to the determination of a limited range of analytes in defined matrices. Enzyme-based biosensors, principally acetylcholinesterase (AChE) inhibition, have been successfully used in environmental analysis for residues of dichlorvos and paraoxon, " carbaryl " and carbofuran. " Immunochemically based biosensors may be the basis for the determination of pesticide residues in liquid samples, principally water and environmental samples, but also fruit juices. The sensors can be linked to transducers, for example based on a piezo-... 

As self-assembly and nanotechnology move from curiosities and demonstrations to more serious means of fabrication and manufacturing, the need for characterization tools, especially those that can meet the time scales for real-time processing, will grow enormously. 

Data reduction and interpretation are much aided by computer methods and the high speed of current microcomputers facilitates the real-time processing and display of data. The principle of extracting as much information as possible from analytical measurements through the application of statistical and other mathematical methods, usually with the aid of appropriate computer software, is known as chemometrics (p. 13). 

Milhlberger, F. Wieser, J. Ulrich, A. Zimmermann, R. Single Photon Ionization Via Incoherent VUV-Excimer Light Robust and Compact TOF Mass Spectrome-i t for Real-Time Process Gas Analysis. Anal Chem. 2002, 74, 3790-3801. 

COGM Real-time process analysis application... 

A real-time process instrument can either be implemented in routine production or be used as a reachback capability for diagnostic purposes during adverse production events. 

In some manufacturing process analysis applications the analyte requires sample preparation (dilution, derivatization, etc.) to afford a suitable analytical method. Derivatization, emission enhancement, and other extrinsic fluorescent approaches described previously are examples of such methods. On-line methods, in particular those requiring chemical reaction, are often reserved for unique cases where other PAT techniques (e.g., UV-vis, NIR, etc.) are insufficient (e.g., very low concentrations) and real-time process control is imperative. That is, there are several complexities to address with these types of on-line solutions to realize a robust process analysis method such as post reaction cleanup, filtering of reaction byproducts, etc. Nevertheless, real-time sample preparation is achieved via an on-line sample conditioning system. These systems can also address harsh process stream conditions (flow, pressure, temperature, etc.) that are either not appropriate for the desired measurement accuracy or precision or the mechanical limitations of the inline insertion probe or flow cell. This section summarizes some of the common LIF monitoring applications across various sectors. 

Flnorescent monitoring in its varions forms can be applied to a plethora of real-time process and field analytical problems across various sectors. Given the superior analytical attribntes and ease of use, steady state... 

Will the measurement be made on-line or off-line For on-line analyzers, is there a grab sample port nearby Is the sample stable once it is withdrawn from the process (See Chapter 3 for more information on sampling issues.) Only an on-line analyzer can enable real-time process control. However, an on-line analyzer implementation will generally be more expensive, more complex, and involve more people in more functions than an off-line one. 

As Van der Grinten developed his estimation algorithm for real time process control he also introduced a dead time , the time between sampling and availability of the analytical result. As a measure of reconstruction efficiency he defined the measurability factor... 

The Siro model is a good tool in the development of constituent retrieval algorithms for limb scan measurements. However, the Monte Carlo technique requires a lot of computer time. Faster models need to be developed for near-real time processing of limb spectra to constituent profiles. Siro serves as a reference against which faster but more approximate methods can be validated. 

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