Industrial preparation spectroscopy

Several industrially prepared catalysts of this type had almost all the clusters in the zeolite pores, as shown by EXAFS spectroscopy, transmission electron microscopy, and hydrogen chemisorption (Table 2) EXAFS spectra indicate first-shell Pt-Pt coordination numbers of 4-5, indicating clusters of, on average, about 5-12 atoms. Dark field electron micrographs [30] have led to similar conclusions for industrially prepared catalysts. 

Near-infrared (NIR) spectroscopy is becoming an important technique for pharmaceutical analysis. This spectroscopy is simple and easy because no sample preparation is required and samples are not destroyed. In the pharmaceutical industry, NIR spectroscopy has been used to determine several pharmaceutical properties, and a growing literature exists in this area. A variety of chemoinfometric and statistical techniques have been used to extract pharmaceutical information from raw spectroscopic data. Calibration models generated by multiple linear regression (MLR) analysis, principal component analysis, and partial least squares regression analysis have been used to evaluate various parameters. 

Undeniably, one of the most important teclmological achievements in the last half of this century is the microelectronics industry, the computer being one of its outstanding products. Essential to current and fiiture advances is the quality of the semiconductor materials used to construct vital electronic components. For example, ultra-clean silicon wafers are needed. Raman spectroscopy contributes to this task as a monitor, in real time, of the composition of the standard SC-1 cleaning solution (a mixture of water, H2O2 and NH OH) [175] that is essential to preparing the ultra-clean wafers. 

An unusual method for the preparation of syndiotactic polybutadiene was reported by The Goodyear Tire Rubber Co. (43) a preformed cobalt-type catalyst prepared under anhydrous conditions was found to polymerize 1,3-butadiene in an emulsion-type recipe to give syndiotactic polybutadienes of various melting points (120—190°C). These polymers were characterized by infrared spectroscopy and nuclear magnetic resonance (44—46). Both the Ube Industries catalyst mentioned previously and the Goodyear catalyst were further modified to control the molecular weight and melting point of syndio-polybutadiene by the addition of various modifiers such as alcohols, nitriles, aldehydes, ketones, ethers, and cyano compounds. 

The understanding of phosphors and solid-state luminescence has matured to the point at which relatively rational design and preparation of new light-emitting materials can be achieved. This has resulted from advances in solid-state physics and optical spectroscopy coupled to the development of new chemical synthesis techniques. This has led to the rapid development of phosphors as important industrial/technological materials. Examples of the occurrence of phosphors in everyday use include ... 

Tablets account for more than 80% of all pharmaceutical formulations therefore, the development and implementation of NIR methods for determining APIs in intact tablets is of a high interest with a view to assuring content uniformity and quality in the end product. Blanco et al developed an innovative strategy to prepare calibration samples for NIR analysis by using laboratory-made samples obtained by mixing the API and excipients in appropriate proportions and compacting the mixture at a pressure similar to that used industrially. This way of matching laboratory and production samples affords more simple and robust NIR methods which require the use of neither HPLC nor UV-vis spectroscopy as reference rather, reference values are obtained by weighing during preparation of the samples. The PLS calibration models thus constructed exhibited a good predictive ability with various production batches.

Infrared spectroscopy is a common analytical method used in industry and research. The reader may refer to basic texts such as (12-14) to obtain guidance in the method, instrumentation, sample preparation and interpretation of spectra. 

In the reported experiments, transition metal ion concentrations were typically low, and electrolytes were added, and, hence, the results are not necessarily pertinent to industrial catalyst preparation. However, Raman spectroscopy was also applied for the characterization of mixed metal ion solutions with compositions of industrial relevance (Dieterle, 2001). Figure 7A, for example, shows the Raman spectra of solutions containing molybdenum, tungsten, and vanadium ions as a function of pH. At high pH values, for example, between 9 and 6, Raman bands were observed that evidence M0O42 and V10O286- species. Raman bands of hepta- and octa-molybdate, and decavanadate were observed upon acidification. At the pH... 

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