Preliminary property measurements

Preliminary Property Measurements. Preliminary measurements of second harmonic generating activity on powder samples of Py-D3C, segregated by grain diameter, determined that X for the material is 1/85 20% that of quartz. These measurements also indicated a coherence length at least as long as that of quartz. 

In the third part of the chapter the solid state properties of our block copolymer are examined. The surface energies of these materials are characterized by contact angle measurements. The organization of the polymer chains in the solid state phase is investigated by small-angle X-ray scattering (SAXS) and the gas selectivity of porous membranes coated with these block copolymers is characterized by some preliminary permeation measurements. 

Crippen s book (10) gives an extensive compilation of the techniques of organic compound identification with the assistance of GC. It includes a step-by-step account of the preliminary examination, physical property measurements, and functional group classification tests. 

Table 1 shows preliminary materials properties measured on non-optimized bipolar plate materials produced through initial development work at PFCT Comparisons with published DOE goals are made in the table. Sealing of the plate through - through plate permeability is accomplished through the application... 

It is now possible to carry out bulk-property measurements, at varying levels of precision and sophistication, on the elements through Cf some preliminary measurements are being made on Es. Therefore, emphasis will be placed here on methods and techniques applicable to samples in the milligram to gram range. No attention will be given to the production of actinide metals on an industrial scale. 

The convective wave cycle was described in 5.2.4 but its heat transfer properties not quantified. Critoph and Thorpe [22] and Thorpe [23] have measured the convective heat transfer coefficient between flowing gas and the grains within the bed. Preliminary results imply that the pressure drop through the bed can be expressed by a modified Ergun equation ... 

The first report of current-voltage (I-V) measurements by Zhang and Lieber[I0] suggested a gap in the density of states below about 200 MeV and semiconducting behavior in the smallest of their nanotubes (6 nm diameter). The study that provides the most detailed test of the theory for the electronic properties of the ID carbon nanotubes, thus far, is the combined STM/STS study by Oik and Heremans[l 1], even though it is still preliminary. In this study, more than nine... 

At sufficiently low strain, most polymer materials exhibit a linear viscoelastic response and, once the appropriate strain amplitude has been determined through a preliminary strain sweep test, valid frequency sweep tests can be performed. Filled mbber compounds however hardly exhibit a linear viscoelastic response when submitted to harmonic strains and the current practice consists in testing such materials at the lowest permitted strain for satisfactory reproducibility an approach that obviously provides apparent material properties, at best. From a fundamental point of view, for instance in terms of material sciences, such measurements have a limited meaning because theoretical relationships that relate material structure to properties have so far been established only in the linear viscoelastic domain. Nevertheless, experience proves that apparent test results can be well reproducible and related to a number of other viscoelastic effects, including certain processing phenomena. 

In conclusion, the following experiments on filtration-washing-deliquoring should be performed to produce data (viscosity of liquids, effective solid concentration, specific cake resistance, cake compressibility, etc.) that are necessary to evaluate times of individual steps of filtration at an industrial scale, i.e. to obtain the proper basis for scale-up of filtration processes measure the filtrate volume versus time make marks on your vacuum flask and take down the time when the filtrate level reaches the mark => no more experiments are needed for preliminary evaluations of filtration properties of slurries initially fines pass the filter medium => recirculate them to the slurry,... 

Preliminary measurements of electrical conductivity of the conjugated derivatives of PBTAB, PBTB and PTTB obtained by the above treatment with bromine vapor are poor semiconductors with a conductivity of the order 10 °S/cm which apparently is not due to doping. Subsequent electrochemical or chemical doping of these polymers lead to 4-6 orders of magnitude increase in conductivity. Ongoing studies of the electrical properties of these conjugated polymers with alternating aromatic/quinonoid units will be reported elsewhere. 

It should be stressed that the field-ions related measurements are still of a very preliminary nature. Work is in progress both on determining the fundamental electrical properties of the radon progeny and based on this on the influence on progeny removal of electrode configuration etc. 

The rate of chemical reaction must be measured and cannot be predicted from properties of chemical species. A thorough discussion of experimental methods cannot be given at this point, since it requires knowledge of types of chemical reactors that can be used, and the ways in which rate of reaction can be represented. However, it is useful to consider the problem of experimental determination even in a preliminary way, since it provides a better understanding of the methods of chemical kinetics from the outset. 

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