Choice of operation mode

The choice of operating mode depends upon characteristics of the... 

Choice of Operation Modes and Suitable Imaging Environments... 

The choice of operation modes and, if applicable, suitable imaging environments depend on many factors, including the type of polymer system to be analyzed and the type of information that is required. Biologically relevant materials or effects that are intrinsic to the liquid—solid interface, for instance, require, of course, AFM under liquid. For a number of experiments, these almost trivial considerations dictate the choice and we refer to the hands-on sections in the corresponding chapters for more detailed information. 

Membrane Selection and Module Design Points made above (Section 10.5.1.1) also apply. For MBRs the design of the module and choice of operating mode to deliver shear stress to the total membrane surface is crucial. The various commercial designs described in Section 10.3 have evolved to meet this challenge. 

Liquid chromatography has a number of different configurations with regard to technical (instrumental) as well as separation modes. The HPLC system can be operated in either isocratic mode, i.e. the same mobile phase composition throughout the chromatographic ran, or by gradient elution (GE), i.e. the mobile phase composition varies with run time. The choice of operation... 

Different separation mechanisms, which determine selectivity, can be exploited in HPCE by appropriate choice of operating conditions. There are four principal modes of operation (Table 4.22) and it should be noted that in only one, micellar electrokinetic capillary chromatography (MEKC), is it possible to separate neutral species from one another. 

The use of different electromigration-based separation techniques hyphenated with MS has become a standard technique in modem pharmaceutical analysis. With the possibility of several commercially available instraments, including various interfaces, the coupling between CE and MS can now be easily achieved. Therefore, numerous issues can be resolved according to the wide choice of operation techniques afforded in CE and the various ionization modes and/or analyzers. CE—MS has emerged as a good alternative for trace... 

A DecisionProblem is a design problem requiring a Decision. This can include design decisions related to the final artifact (such as the specification of a chemical plant) like the choice of the mode of operation of a chemical plant or the selection of an appropriate reactor tjrpe, but also decisions referring to auxiliary artifacts like mathematical models. By linking a DecisionProblem to another DecisionProblem by means of the IsASubdecisionOf relation, it can be stated that solving the latter problem requires solving the former. The semantics of IsASubdecisionOf does not require the sub-decisions to be independent of each other nor does it require the entirety of sub-decisions to describe the complete DecisionProblem. 

The major discussion will be based on fee DSC shown in Fig. 4.85 which is a further development of fee DSC A of Fig. A.9.2, i.e., TMDSC is an added choice of operation, not a new instrament. It will be advantageous to do some sample characterizations in fee DSC mode, others in the TMDSC mode. It was noted in Sect. 4.3 that DSC could be used as a calorimeter or as DTA, similarly TMDSC can... 

After defining the interface s functionalities, the next step deals with the specifications of the views (Fig. 2). These specifications must take into account the fact that the views which must be developed correspond to both the normal and the abnormal operation modes. We can break this specification step down into two parts the first one concerning the content and the organization of the views, and the second one dealing with the choice of the modes of presentation of the information ... 

The UV-Visible detector is the universal detector used in analytical and preparative CCC. It does not destroy solutes. It is used to detect organic molecules with a chromophore moiety or mineral species after formation of a complex (for instance, the rare earth elements with Arsenazo III ). Several problems can occur in direct UV detection, as has already been described by Oka and Ito 1) carryover of the stationary phase due to improper choice of operating conditions, with appearance of stationary phase droplets in the effluent of the column 2) overloading of the sample, vibrations, or fluctuations of the revolution speed 3) turbidity of the mobile phase due to difference in temperature between the column and the detection cell or 4) gas bubbling after reduction of effluent pressure. Some of these problems can be solved by optimization of the operating conditions, better control of the temperature of the mobile phase, and addition of some length of capillary tubing or a narrow-bore tube at the outlet of the column before the detector to stabilize the effluent flow and to prevent bubble formation. The problem of stationary phase carryover (especially encountered with hydrodynamic mode CCC devices) can be solved by the addition between the column outlet and UV detector of a solvent that is miscible with both stationary and mobile phases and that allows one to obtain a monophasic liquid in the cell of the detector (a common example is isopropanol). 

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