Tools continuous flow

Lean Tool Continuous Flow/Cycle Time Gains... 

The properties required of a material in order for it to support a stable shock wave were listed and discussed. Rarefaction, or release waves were defined and their behavior was described. The useful tool of plotting shocks, rarefactions, and boundaries in the time-distance plane (the x-t diagram) was introduced. The Lagrangian coordinate system was defined and contrasted to the more familiar Eulerian coordinate system. The Lagrangian system was then used to derive conservation equations for continuous flow in one dimension. 

Tubular reactors have been the main tools to study continuous flow processes for vapor or gas-phase reactions. These are also used for reaction in tv o flowing phases over a solid catalyst. When the catalyst is in a fixed bed, the contact between the liquid on the outside surface of the particulate is uncertain. For slurry-type solid catalyst the residence time of the catalyst or the quantity in the reactor volume can be undefined. 

Various experimental methods to evaluate the kinetics of flow processes existed even in the last centuty. They developed gradually with the expansion of the petrochemical industry. In the 1940s, conversion versus residence time measurement in tubular reactors was the basic tool for rate evaluations. In the 1950s, differential reactor experiments became popular. Only in the 1960s did the use of Continuous-flow Stirred Tank Reactors (CSTRs) start to spread for kinetic studies. A large variety of CSTRs was used to study heterogeneous (contact) catalytic reactions. These included spinning basket CSTRs as well as many kinds of fixed bed reactors with external or internal recycle pumps (Jankowski 1978, Berty 1984.)... 

Micro reactors are continuous-flow devices consuming small reaction volumes and allowing defined setting of reaction parameters and fast changes. Hence they are ideal tools for process screening and optimization studies to develop solution-based chemistries. 

The previous two sections described the development of hp-xenon techniques for the investigation of gas dynamics in porous or opaque media. The usefulness of continuous flow hp-xenon as a tool for dynamic NMR imaging experiments was... 

A recent new trend called Active Learning substitutes the often assumed static setting of training and test set in which a learning machine is applied by the probably more realistic scenario of a continuous flow of data. The outcome of experiments influences the choice and generation of subsequent data points [155]. Active Learning provides tools that help select the most promising next subset of data to be subjected to experimentation [156]. 

The stopped-flow method is a routine laboratory tool, whereas the continuous-flow apparatus is used in a few specialized cases only. The stopped-flow technique requires only 100 to 400 /XL of solution or less for the complete time course of a reaction the dead time is as low as 0.5 ms or so and observations may be extended to several minutes. Stopped flow does, however, require a rapid detection and recording system. 

Mass spectrometry is a valuble tool with which an abundancy of structural information may be obtained from a minute amount of material. Capillary electrophoresis may be interfaced with mass spectrometry by electrospray ionization [124-126] or continuous-flow, fast-atom bombardment methods [127,128]. Several reviews discuss applications of the interfacing techniques, and address the attributes and disadvantages associated with these methods [129,130]. Critical parameters involved in the optimization of CE-electrospray ionization mass spectrometry analysis have been reviewed as well [131],... 

Having discussed some of the advantages associated with the use of microreaction technology as a tool to conduct high-throughput organic synthesis, the final section of this chapter focuses on some of the compounds generated under continuous flow that are of synthetic and/or industrial interest. 

Croft, D. J. and Pye, K. (2003). The potential use of continuous-flow isotope-ratio mass spectrometry as a tool in forensic soil analysis A preliminary report. Rapid Commun. Mass Spectrom. 17, 2581-2584. 

As a new class of materials, ionic liquids require special analytical methods. In the case of imidazolium halides and similar compounds the most common impurities are amines, alkyl halides and of course water. Seddon et al. described a method for the detection of residual amines using the strong UV absorbance of copper tetramine complexes. These complexes are readily formed by the addition of Cu2+ ions [24]. The detection of both amines and alkyl halides is possible by NMR spectroscopy but with limited resolution [25]. By far the most powerful analytical method is liquid chromatography combined with UV detection. This sensitive method allows the detection of traces of amines and halides [26]. Unreacted amines can be also detected by ion chromatography combined with a suppressor module. In this case detection is achieved using a continuous flow conductivity cell since amines are protonated and thus detectable. For traces of other ionic impurities ion chromatography is also the most powerful analytical tool [27]. Finally, residual water can be quantified using Karl Fischer titration or coulometry [28]. 

The increasing availabihty of mass spectrometers and on-Hne interfaces for sample preparation has made natural abundance measurements accessible to a broad community of biological oceanographers, and stable isotope measurements are becoming a routine tool in studies of marine ecosystems. In general, measurements are now carried out with continuous flow systems that integrate a... 

Continuous-flow (chemostat) culture the culture is completely homogeneous for long periods of time whilst cells are in a steady state (see section 5.6). An extremely useful tool for physiological studies but not very economical for production (by definition, cells are never at maximum density)... 

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