Characterisation techniques

Nuclear magnetic resonance is another characterisation technique of great practical importance, and yet another that became associated with a Nobel Prize for Physics, in 1952, jointly awarded to the American pioneers, Edward Purcell and Felix Bloch (see Purcell et at. 1946, Bloch 1946). In crude outline, when a sample is placed in a strong, homogeneous and constant magnetic field and a small radiofrequency magnetic field is superimposed, under appropriate circumstances the... 

This brief outline of the gradual solution of a crucial characterisation dilemma in polymer science could be repeated for other aspects of characterisation in polymer science, as in other parts of MSE, characterisation techniques and theories are crucial. 

Silver nitrate (AgN03) is a compound that fulfills the precedent requirements (Till = 212°C), and also it can be easily decomposed into pure silver by thermal treatment at 400 °C. As mentioned before, the basic characterisation technique for this studies is transmission electron microscopy (TEM) the atoms with rather high atomic number would facilitate the detection of the nanorods. 

Most of our results have been obtained by TEM studies of individual tubes that can be considered nanolaboratories the ability to control and observe such small objects is very impressive. However, it also strains a limitation concerning the lack of an efficient method to generate macroscopic quantities of filled tubes, where we could be able to apply conventional macroscopic characterisation techniques. 

Tong HM, Nguyen LT (eds) (1990) New characterisation techniques for thin polymer films, J Wiley, New York... 

This chapter is organised as follows Following this introduction as section 1, a brief description of the synthesis and characterisation techniques used for the as-synthesised polymer capped selenide nanopartides is given as section 2. In section 3, the mechanism of the reaction, results and discussion of the different selenide nanocomposites obtained using different polymers are given. Section 4, the last section gives a summary of the whole process, followed by references. Acknowledgements are cited before references. 

The reaction on the catalyst surface was followed by in situ i.r. spectroscopy using a Bruker IFS88 FTIR spectrometer for the characterisation of sorbed species and mass spectroscopy for the analysis of gas phase. The state of Pt was further investigated by in situ X-ray absorption spectroscopy (Daresbury, UK, beamline 9.1, transmission mode, Si(220) monochromator, Pt-Lj, edge). Details of catalyst characterisation techniques are reported elsewhere [13,14]. 

The polymer characteristics addressed within these clusters are presented below in Table 1. Table 1 presents an overview of the many analytical/ characterisation techniques and methods used for the molecular characterisation... 

As is evident in the many examples selected in this chapter to illustrate the molecular characterisation and analysis of polymer degradation and oxidation processes, almost, without exception, each study or investigation cited has involved use of more than one analytical method or characterisation technique, often many more than two. This clearly emphasises the importance of using a multi-technique approach to provide supportive, complementary and confirmatory information, since each technique or method yields a different aspect of the degradation/oxidation process in polymers. 

A. Gupper, Doctoral Thesis Enhanced Applications of Microscopic Characterisation Techniques in Materials Science, Graz University of Technology, 2003. 

The development of catalysts includes both practical and theoretical knowledge and experience with a palette of disciplines known to the chemical engineer, e.g. inorganic chemistry, physical and chemical characterisation techniques, nano-scale materials, unit operations, chemical reaction engineering, catalyst kinetics, and transport phenomena. 

The desirability of using a non-invasive in-situ probe has already been discussed. There is, however, a problem, in that standard characterisation techniques are unable to penetrate bulky reaction vessels. As a result of this, little is known about the reaction dynamics or kinetics of intercalation reactions. A non-invasive probe which can interrogate a typical intercalation process is required. It is also necessary to employ short data collection times in order that kinetic information may be obtained. X-ray powder diffraction is a highly appropriate tool. It is non-invasive, and is a powerful characterisation technique when used in combination with ex-situ analyses. 

Angular-dispersive X-ray diffraction is used as a standard characterisation technique in the majority of solid-state laboratories. In this method, a constant-wavelength X-ray source is used. A detector sweeps a range of angles, and therefore Bragg reflections are separated by a spatial coordi-... 

Foams 2000 Second International Conference on Thermoplastic Foam. Conference proceedings. Parsippany, N.J., 24th-25th October 2000, p. 139-48 USING POLYMER CHARACTERISATION TECHNIQUES TO PREDICT LDPE RESIN SUITABILITY FOR EXTRUDED FOAM APPLICATIONS Anger J Ngnyen L Nova Chemicals Corp. 

Ferrisilicate zeolites wherein iron ions replace silicon in the lattice framework have potential as catalyst in various conversion processes. During the past decade ferrisilicate analogs of sodallte, MFI, M, MTT, EUO, MTW, FAU, BETA, MOR and LTL have been synthesised and characterised by various physicochemical techniques as well as catalytic reactions. After a review of the general synthesis procedures a list of criteria is presented to confirm the location of Fe in the zeolite framework. Examples are provided to illustrate the utility of the various characterisation techniques. 

This chapter initially provides an overview of the considerations associated with the synthesis of inorganic polymers and the reasons why inorganic rings are so important as polymer precursors. The methods commonly used to characterise polymers are then discussed. As in Chapter 3, which describes the techniques used for the characterisation of inorganic rings, this section focuses on utility rather than on theoretical and practical details of the different methods. The reader is referred to a variety of texts for further details about these polymer structural characterisation techniques. ... 

The characterisation techniques discussed in this chapter are of a fairly general nature. Specialised techniques applicable to particular problems are discussed as the questions arise in the text. 

The last decade has seen the introduction of several new characterisation techniques which have been of major assistance in understanding the structure of monolayers at a molecular level. The most important of these has been the use of synchrotron radiation to obtain diffraction patterns from films at the air/water surface. In principle it would always have been possible to use X-rays for this purpose but the high intensity and highly monochromatic nature of the radiation from a synchrotron source has made this technique far easier to use. A selection of recent papers based on this technique is given [79-88], not all of which refer to simple fatty acids. The information available from such experiments is of two distinct kinds, though, in several studies, both kinds of information have been obtained. 

So far, few authors [7,8] have reported X-ray reflectivity data for nitrides. This technique offers a very precise method of measuring the thickness of layers thinner than about 2000 A and their roughness. With a growing number of nitride samples of a very small roughness, reflectivity will soon become a commonly used characterisation technique. However, one should be aware that the level of surface roughness obtained from reflectivity often does not coincide with the data of atomic force microscopy (AFM) or even optical microscopy. This is because each technique has a different length scale and studies using complementary methods are necessary to obtain a real model of the surface. 

HAuC14 solution pH or range of pH of predominance of the various Auln speciation Characterisation technique References... 

Each of the three characterisation techniques explored in the present study can be criticised in terms of experimental procedure or mathematical interpretation of the raw data. Nevertheless, in the present study, a remarkable agreement is obtained between the results obtained with the three techniques. It is interesting to note that this is the case with such large pore samples of heterogeneous pore size distribution. These results are in good agreement with comparison studies carried out on other more ordered pore systems [6]. 

The honeycomb monoliths were dried at room temperature and then heated in air to 150°C for 4h. Samples of each composite were also heat-treated at 500°C or 850°C in nitrogen. Heat-treatment in an inert atmosphere was necessary to avoid oxidation of the AC. These materials were subsequently used in all of the characterisation techniques and adsorption performance tests. 

CHARACTERISATION TECHNIQUES FOR CROSS-LINKED VINYL POLYMERS AND MIPS... 

---