Other measurement methods

This subchapter summarizes aU other experimental methods mentioned in subchapter 4.4.1 in order of their special importance and use regarding the determination of solvent activities in polymer solutions. 

Apart from VLE-measurements, membrane osmometry is the next important method that has been used for measuring solvent activities in polymer solutions. This follows from the 

Laboratory designed instruments were developed in the 40 s and 50 s, e.g. by Zimm or by Flory. Later on, high speed membrane osmometers are commercially available, e.g., from Knauer, Hewlett-Packard or Wescan Instruments. External pressures may be applied to balance the osmotic pressure if necessary, e.g., Vink. The principle scheme of a membrane osmometer together with the corresponding 

Some efforts are neeessary to keep the osmometer under appropriate working eondi-tions. This relates mainly to the proper preeonditioning and installation of the membrane, the attainment of thermal equilibrium, the ealibration of the eleetronie output, the adjustment of solvent zero, and to ehoosing the desired sensitivity. 

The relation between osmotie pressure and solvent aetivity is to be found from the ehemieal potential equilibrium eondition, taking into aeeount the pressure dependenee of ti. From the rules of phenomenologieal thermodynamies, one obtains  

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In comparison with other measurement methods, NMR has important strengths. Its great virtue is its noninvasive nature, allowing one to obtain spatially resolved metabolic profiles and to investigate metabolomics in vivo. 10 There is little or no sample preparation. It is nondestructive. It is information-rich with regard to the determination of molecular structures because it can detect different chemical groups of metabolites simultaneously. 

As a variation we discuss in the present paper an even simpler procedure where we make use of only two measured points (2PM). In our paper we compare both methods and we assess the accompanied increase of measurement inaccuracy. Though the following approach is based on gravimetric measurements it is valid likewise for any other measuring method e.g. the volumetric one. 

The plasticity readings obtained from the Brabender measuring kneader expressed in the form of torque figixres are not identical with the plasticity figures relevant to extrusion. This also holds true for those measured values determined by the penetrometer or other measuring methods. Yet the Brabender measuring kneader is ideally suited for the development or optimisation of bodies which need to be plastified prior to extrusion by means of continuous or intermittent kneading. 

Safety relevant characteristics such as explosion limits and ignition energies are not scientifically well-defined properties of the gas. They rather serve for comparison purposes and are always associated with a very specific, well-defined measurement method under precisely defined conditions (pressure, temperature, humidity, etc.). Other measurement methods yield different results, and an accident situation is quite different again. The purpose of these characteristics suits mainly the safety relevant comparison and the characterization of different substances. 

There are, however, other measurement methods developed mainly for routine process control in radiation processing, such as high-frequency conductivity (oscillometric) analysis, spectrophotometric evaluation, and conductivity measurement. 

In this chapter we shall describe the experimental techniques for the generation and detection of excess charge carriers in nonpolar liquids. Some of the underlying physical principles are discussed in Chapters 3 through 6. The review of the various techniques cannot be complete. We concentrate here on modem methods which make use of advanced electronic measurement apparatuses. Other measurement methods are described in the classic book by Adamczewski to which the reader is referred (Adamczewski, 1969). 

Another study which employed RT EPR (complementary to other measurement methods) involved water-soluble blends of sulfosalicylic acid protonated-PANI with poly(vinyl alcohol) (PVA, 10-70 wt%), synthesized by inverted emulsion and emulsion polymerization [98]. Although the mechanical properties and blend morphology were found to depend on the method of synthesis, the EPR spectral parameters were similar for both preparations (symmetric lines of width 2-5 G, with g in the range 2.0025-2.0046), typical for the PANI salt. 

The results obtained with the ECROM were compared to those obtained with other measurement methods and devices reported in literature such as ... 

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