Mettler

Mettler softening point method — ASTM D 3461-76. This is the most recent method. This automatic method measures the temperature at which the resin flows out of a sample cup under its own weight. The temperature is recorded when the first drop crosses the light path of a photocell (Fig. 21). This method is quite accurate and reproducible. 

Fig. 21. Determination of the Mettler softening point. 1, heating element 2, platinum resistance thermometer 3, sample 4, light source 5, furnace 6, sample cup 7, photo cell 8, collector sleeve (see p. 48 in [25]).

Mettler softening point provides the lowest for a given resin. Therefore, both the softening point value and the method used for its determination should be given. In general, manufacturers supply the resins with a tolerance of about 3°C in the Ring and Ball (R B) softening point. 

Mackenzie, A.E., Allen, G., Lahey, D., Crossen, M.L., Nolan, K., Mettler, G., Worton, R.G., MacLen-nan, D.H., Korneluk, R. (1991). A comparison of the caffeine halothane muscle contracture test with the molecular genetic diagnosis of malignant hyperthermia. Anesthesiology 75,4-8. 

Dynamic calorimetric measurements were made on 10 mg samples in sealed aluminum pans over the temperature range 50°C to 220°C at 10°C/min using a Mettler thermoanalytical system consisting of a DSC, model 20 and processor, model TC-lOA, which performed the data handling. 

Figure 7. Configuration of the materials durability test system 1, Zymark robot arm 2, Mettler balance 3, blotting station 4, capping station 5, specimen rack 6, water bath 7, block oven 8, vacuum oven 9, freezing chamber 10, NDT station 11, automated micrometer, and 12, washing station. O, specimen holder.

At present, several companies offer reaction calorimeters. Below, the specifications of the most commonly used commercial calorimeter (RKl of Mettler) are given ... 

AccessChrom or TurboChrom data acquisition software, running on a MicroVax Balance, Analytical PM 2000, Mettler Balance, top loading, Mettler... 

Electronic analytical and top loading balances, Mettler or equivalent Sample chopper, Hobart, or equivalent... 

Mettler F, Moseley R. 1985. Medical effects of ionizing radiation. New York Grune and Stratton. 

Mettler-Toledo, Collected Applications Thermal Analysis Food, Schwerzenbach (1998), pp. 47-8. 

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. 

Considering the related Mettler DL 40 and DL 40 RC MemoTitrators, the DL 40 can be used for ten different volumetric and potentiometric methods titration to a pre-selected absolute (EPA) or relative (EPR) end-point equilibrium titration (EQU)-recording titration (REC)-incremental titration (INC) Karl Fischer water determination (KF)-controlled dispensing (DOSE) pH and pX measurements (pX/E) multi-level titrations and back-titrations with automatic calculation (CALC) and manual titration (MAN)-automatic calibration of electrodes (CAL). 

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. 

The Metrohm E 636 Titroprocessor (Fig. 5.12) offers in principle the same possibilities as the Mettler MemoTitrators, but with some additional features concerning its operation, illustrated by the schematic diagram in Fig. 5.13, using the usual microprocessor terminology62 1, CPU 2, RAM 3, ROM 4, Bus 5, I/O interface 6,16-place alphanumeric display 7, numerical push-buttons 8, function and control buttons 9, card reader (for routine analysis) 10, alphanumeric thermoprinter for curves (normal and first derivative) and data on... 

Imanidis G, C Waldner, C Mettler, H Leuenberger. (1996). An improved diffusion cell design for determining drug transport parameters across cultured cell monolayers. J Pharm Sci 85 1196-1203. 

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. 

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