Mettler apparatus

The resins were tested dynamically by thermomechanical analysis (TMA) on a Mettler apparatus. Triplicate samples of beech wood alone, and of two beech wood plies each 0.6 mm thick bonded with each resin system, for sample dimensions of 21 X 6 X 1.2 mm were tested in non-isothermal mode between 40°C and 220°C at a heating rate of 10°C/min with a Mettler 40 TMA apparatus in three-point bending on a span of 18 mm. A force varying continuosly between 0.1 N, 0.5 N and back to 0.1 N was appUed on the specimens with each force cycle of 12 s (6 s/6 s). The classical mechanics relation between force and deflection E = [L /(4fc/i )][ AF/( A/)] (where L is the sample length, b and h are the sample width and thickness, AF is... 

In 1976, Radiometer61 presented for the first time a microprocessor-controlled titration system. Since then, the microprocessor has been used preferentially and as a fully integrated part (in line) in electroanalytical instruments as a replacement for the on-line microcomputer used before. Bos62 gave a comprehensive description of the set-up and newer developments with microprocessors in relation to microcomputers and indicated what they can do in laboratory automation. Many manufacturers are now offering versatile microprocessor-controlled titrators such as the Mettler DL 40 and DL 40 RC MemoTitrators, the Metrohm E 636 Titroprocessor and the Radiometer MTS 800 multi-titration system. Since Mettler were the first to introduce microprocessor-controlled titrators with their Model DK 25, which could be extended to a fully automated series analysis via the ST 80/ST 801 sample transport and lift together with the CT 21/CT211 identification system, we shall pay most attention to the new Mettler MemoTitrators, followed by additional remarks on the Metrohm and Radiometer apparatus. 

Although the DL 40 was capable of performing Karl Fischer water titrations and Mettler developed a separate microprocessor-controlled push-button operated DL 18 KF titrator, they also introduced as an all-purpose apparatus the improved DL 40 RC (see Fig. 5.11) with a dual titration head and with a modified software program to handle the new two-component titrants for Karl Fischer titration (see pp. 204-205). The instrument can also be expanded into an automatic series titrator by connecting the RT 40 sample transport for 16 samples and storage of 50 sample weights from a connected balance this series routine can be interrupted at any time after completion of the titration in progress. 

APPARATUS AND MATERIALS. A Mettler DL40 memotitrator, DK19 Filter Titrator with filters and a DK181 Phototrode were purchased from M.S.E. Scientific Instruments, Crawley. Visible spectra were recorded on a Perkin Elmer Lambda 3 spectrophotometer. 

The fresh and spent catalysts were characterized with the physisorption/chemisorption instrument Sorptometer 1900 (Carlo Erba instruments) in order to detect loss of surface area and pore volume. The specific surface area was calculated based on Dubinin-Radushkevich equation. Furthermore thermogravimetric analysis (TGA) of the fresh and used catalysts were performed with a Mettler Toledo TGA/SDTA 851e instrument in synthetic air. The mean particle size and the metal dispersion was measured with a Malvern 2600 particle size analyzer and Autochem 2910 apparatus (by a CO chemisorption technique), respectively. 

Melting Point-Mettler Dropping Point (Cc 18-80) determines the temperature at which a sample becomes sufficiently fluid to flow in a specified apparatus the major melting point determination method used by domestic industry. 

As shown in Fig. 4.8.1, a TG apparatus typically consists of a (1) recording balance, (2) furnace, (3) furnace temperature controller, (4) temperature programmer, (5) temperature detector, and (6) recorder. Most commercial models, e.g., Perkin-Elmer Model TGA-7, TA Instruments 2950 TGA, Mettler TC11ATG50, Seiko Instruments SSC 5200 TG-DTA 220, and Shimadzu TGA-50, consist of these basic components. 

In the laboratory we have several automatic and semiautomatic robotic apparatus including the IRORI Nanokan optical encoding system for split- and pool-synthesis (34) and synthesizers from Advanced ChemTech and the MiniBlock from Mettler, Toledo, OFI. 

Claudy et al. (14, 15) used an electrical analog model of a heat flux DSC apparatus with the numerical values of the resistors computed using a Mettler TA 2000B DSC apparatus. 

Wendlandt (45) used a microscopic method for the determination of the reflectance of the sample. The apparatus, as shown in Figure 9.28, consisted of a low-power (100 x, generally) reflection-type microscope, A, which is illuminated by means of a monochromator, B. The reflected radiation is detected by a photomultiplier tube, C, and amplifier, D, and recorded on either an X-Y recorder, E, or a strip-chart recorder, F. In order to heat the sample to 250°C, a Mettler Model FP-2 hot stage, G, is employed. Either isothermal ( 1CC) or dynamic sample temperatures may be attained by this device. The sample is moved through the illuminated optical field by means of the reversible motor, H. The motor is reversed at preset intervals by a relay circuit and timer, J. Thus, it is possible to scan the reflectance from the sample, which may consist of a single crystal or a powdered mixture. Powdered samples may be placed directly on the heated microscope slide or... 

Figure 9.28. Microreflectance apparatus. A, B L microscope B. B L monochromator and lamp C, photomultiplier tube D, amplifier and power supply E, X-Y recorder F, strip-chart recorder G. Mettler hot stage H, reversible motor J, relay and timer (45).

Figure H.3. Mettler TMA 40-TMA apparatus A, measuring sensor B, sample support C, purge gas inlet D, linear variable differential transformer E, linear motor coil F, linear motor stator. 

The V-Al oxide precursor was prepared by co-precipitation of ammonium metavanadate and aluminum nitrate solutions [2,7,8]. At the lab-scale (up to 100 g of solid), a 6-liter temperature-regulated glass reactor (LabMax from Mettler) equipped with a U-type impeller was used for the precipitation. This apparatus allows to control and record the pH, temperature, rates of reactants addition, and stirring during the whole precipitation process. At pilot-scale (1 kg of solid), an 80-liter stainless steel precipitation tank was used. This tank is equipped with a double jacket for heating or cooling the slurry, pH and temperature control systems. The stirring in the tank was achieved with a propeller (boat-like) at about 200 rpm. For both scales, the pH... 

Fig. 8. Schematic description of an apparatus for simultaneous visual and DSC observations using the Mettler Thermosystem FP800 (Reprinted with permission from [108])...

For further characterization, degradation of the polymer was studied using the Mettler thermogravimetric apparatus. Figure 10 shows the weight loss curves for atactic PPBA when heated at 6°C/min. No appreciable weight loss occurred at temperatures up to 613°K. Isotactic polymers showed similar traces and no appreciable degradation occurred at temperatures less than 573°K. 

TMA tests were carried out on the dried, lignin impregnated papers. Tensile tests on the dry specimens were conducted on a Mettler 40 TMA apparatus. The specimen was subjected to an oscillahng force. The Young s modulus was obtained as a funchon of temperature by applying the formula ... 

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