Characterization after drying

A narrow beam, attainable with Raman, was used by Schuster et al.4 to characterize the population distribution in Clostridium cultures. The technique was applied to the acetone-butanol (ABE) fermentation process in which the solventogenic Clostridia go through a complex cell cycle. After drying the cells on calcium fluoride carriers, single-cell spectra were obtained. Cells of different morphology showed different spectra. A number of cell components could be detected and varied in quantity. The approach was seen to be far faster than conventional methods. 

All experiments on the characterization of dye-clay composites were performed after drying overnight at 100°C in air, which should lead to the expulsion of... 

Alcohol (5 mmol), catalyst 1 (5 mol %, 84 mg) and TEMPO (5 mol %, 39 mg) were stirred at ca. 100 °C in toluene (10 mL) under atmospheric oxygen for the appropriate time (Table 5.1). After completion, the reaction mixture was treated with water (3 mL) and the organic layer, after drying over sodium sulfate and GC analysis, was passed through a short pad of sihca gel using ethyl acetate (or diethyl ether) and hexane as an eluent to provide the analytically pure aldehyde which was characterized by NMR, IR and mass analysis. 

IR Data Characterizing Selected Phosphorus-Based Catalysts after Drying and Calcination... 

A typical reaction procedure was as follows a mixture of zeolite (5 g) and amide (10 mmol) in an appropriate solvent (25 ml) was vigorously stirred under reflux at 75°C (using a thermostated bath) under nitrogen atmosphere. The reaction was periodically monitored by GLC. At the end of the reaction, the mixture was filtered and the cake washed with methanol and diethyl ether. After drying with anhydrous sodium sulfate, the solvent was evaporated and the residue purified by distillation or crystallization. The known compounds were characterized by their GC/MS spectra, as well as by their melting points or boiling points, by comparison with standards. 

If no commercial catalyst is available, it may still be advantageous to separate catalyst optimization from development of a coating procedure. Such an approach was pursued by Schwarz et al. [178] in the development of a catalytic microreactor for the partial oxidation of propane. In a first step, a VOY/ A1203 catalyst was developed. A commercially available Y-AI2O3 powder consisting of particles 3 pm in diameter was chosen as the support material, mixed with various amounts of vanadyl acetylace-tonate and suspended in methanol. After drying and calcination, the resultant material was characterized and its catalytic activity and selectivity for the partial oxidation of propane was determined. The optimized catalyst was resuspended in an alcoholic solution, mixed with binders, and coated onto a stainless steel MSR. 

At selected aging times t, samples are taken for experimental characterization. After three months of immersion, some samples are re-dried under thermal aging conditions at 40 °C and 60 °C, respectively. With the dry samples, the effect of aging in the epoxy network is studied without artifacts from evaporating water during the experiments. 

The synthesis of Sn-beta (68,151) with isolated single tin sites was accomphshed in a fluoride medium TEOS was hydrolyzed in a stirred aqueous solution of TEAOH. Then a solution of SnC 5H2O in water was added and the mixture stirred until the ethanol formed by hydrolysis of the TEOS had evaporated. HF was added to the resulting clear solution, and a thick paste formed. Then a suspension of nanocrystalline seeds (20 nm in diameter) of dealuminated zeolite beta in water was added. The crystallization was carried out in aTeflon-hned stainless-steel autoclave, which was heated to a temperature of 140 °C and continuously rotated for 20 days. After drying and calcining of the resultant sohd, XRD showed that a highly crystalline material with BEA structure was obtained, which contained 1.6 wt% Sn according to chemical analysis. Further characterization by XRD and UV, IR, and Sn MAS NMR spectroscopies verified the structure and the isomorphous substitution of siHcon by tin. 

After drying in vacuum the polymers were characterized by elemental analyses, FTIR- and solid-state Si-NMR spectroscopy. Three examples are shown in Fig. 1. The strong absorption bands around 2150 cm in the FTIR spectra indicate that in all cases the carbodiimide unit is present in the polymers. Besides, a significant number of trimethylsilyl endgroups are detected by the signal around 0 ppm in the Si-NMR spectra (Fig. 1). 

The partial wet natural fibres were poured into a glass tray (lOx 10x0.2 cm ) to form a dried sheet having 0.1 mm in thickness. After drying at 50 °C in an oven for 24 h, the natural fibre sheet was kept in a desiccator before characterization. The average particle size of coconut waste before and after the milling process was about 350 and 950 pm, respectively, as shown in Figure 13.6. 

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