Real-time synthesis

Real-time synthesis of operating procedures. Most of the ideas and methodologies, presented in this chapter, are applicable to the a priori, off-line, synthesis of operating procedures. There is a need though to address similar problems during the operation of a chemical plant. Typical examples are the synthesis of operational response (i.e., operating procedure) to process upsets, real-time recovery from a fallback position, and supervisory control for constrained optimum operation. 

Porcaro et al., 1995] Porcaro, N., Scandalis, P., Smith, J. O., Jaffe, D. A., and Stilson, T. (1995). SynthBuilder—a graphical real-time synthesis, processing and performance system. In Proc. 1995 Int. Computer Music Conf, Banff, pages 61-62. Computer Music Association. See http //www-leland.stanford.edu/group/OTL/Synth-Builder.html for information on how to obtain and run SynthBuilder. See also http //www-ccrma.stanford.edu for related information. 

MattiKarjalainen, Unto K. Laine, Timo I. Laakso, and Vesa Valimaki. Transmission-Line Modeling and Real-Time Synthesis of String and Wind Instruments. Proceedings of the International Computer Music Conference 293-296 (1991). 

Nadine Miner. Creating Wavelet-Based Models for Real-Time Synthesis of Perceptually Convincing Environmental Sounds. Ph.D. Dissertation, University of New Mexico (1998). 

It is particularly important to study process phenomena under dynamic (rather than static) conditions. Most current analytical techniques are designed to determine the initial and final states of a material or process. Instmments must be designed for the analysis of materials processing in real time, so that the cmcial chemical reactions in materials synthesis and processing can be monitored as they occur. Recent advances in nuclear magnetic resonance and laser probes indicate valuable lines of development for new techniques and comparable instmmentation for the study of interfaces, complex hquids, microstmctures, and hierarchical assemblies of materials. Instmmentation needs for the study of microstmctured materials are discussed in Chapter 9. 

The presence of triethylenetetramine in the hydrothermal synthesis of open-framework zinc phosphates results in a number of frameworks with one- to three-dimensional structures. The structures include one-dimensional ladders, two-dimensional layer structures, and one structure where the tetramine is bound to the zinc center. The structural type was highly sensitive to the relative concentration of the amine and phosphoric acid.411 Piperazine and 2-methylpiperazine can be used as templating molecules in solvothermal syntheses of zinc phosphates. The crystallization processes of the zinc compounds were investigated by real time in situ measurements of synchrotron X-ray powder diffraction patterns.412... 

The SmithSynthesizer and SmithCreator are systems devoted to laboratory synthesis. They are constituted by a closed rectangular waveguide section playing the role of cavity. They can use specific cylindrical tubes. Pressure and temperature sensors allow real-time monitoring and control of operating conditions. This system was a good solution for laboratory experiments. The SmithSynthesizer is described by Fig. 1.13. More details about the SmithSynthesizer could be found in Sect. 12.7 in Chapt. 12. 

The axon comprises a major portion of the total volume and surface area in most neurons and may extend several thousand cell body diameters. Since the genetic material and nearly all the protein synthesis machinery are localized to the cell body, a supply line is maintained to provide structural and functional materials to sites all along the length of the axon. Insights as to how neurons accomplish this task can be obtained by real-time imaging of living axons with video-enhanced light microscopy [1] (Fig. 28-1). 

The development phase invokes many instances where reactions must be optimised quickly because of changes in the route to or specification of the drug substance. The final challenge is to converge upon the most appropriate and environmentally acceptable methods for manufacture. In identifying optimal synthesis conditions, real-time tuning of a mi-... 

Fig. 11. Real-time, in-line temperature monitoring for an ionic-liquid synthesis when varying external bath temperature and volume flow...

De Mello et al. have constructed a so-called pSYNTAS (miniaturized synthesis and total analysis system). The system was used to perform an Ugi-type reaction to form several a-aminoacetamides from amines, isocyanates and formaldehyde in the presence of water (Scheme 25) [56-58]. The reported system consists of a glass/silicon nanoreactor [59] in connection to a TOF-MS for the real-time online analysis of the reaction stream. Reactions were conducted in the 600 nl volume chip under continuous flow of 20-2 pl/min flow rate. Reduced flow rates resulted in increased outputs. The analyzed outlet flow showed high yields of the desired products with small quantities of starting materials and intermediates (no exact yields were reported). 

Using the PETIS, real-time [ CJmethionine translocation was studied for barley. For the mechanism of Fe uptake in an Fe-delicient barley, it was found that leaf methionine does not participate in the reaction of mugineic acid synthesis, but the methionine produced in barley roots is used in the biosynthesis of mugineic acid phytosiderophores [131,132]. 

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