Micromet Instruments

Fig. 8. Schematic top view of actual microdielectrometer sensor, illustrating the comb electrode structure, field effect transistors and thermal diode temperature indicator. (Reprinted with permission of Micromet Instruments, Inc.)...

Micromet Instruments, Inc., Cambridge, MA The Eumetric System II Microdielectrometer, Product Bulletin, 1985... 

The author would like to express his gratitude to David Day of Micromet Instrument... 

In terms of equipment. McDonnell Douglas proposes an automated ultrasonic scanning system (AUSS) with 9 axes of motion, a 7 axes ultrasound system (ADIS-II) and a portable inspection system (MAUS II) for aerospace composite structure inspection [36], The ultrasonic resin analyser (URA 2002A from Quatro Technologies) can be used to measure the resin content in polymer based composites [10]. The UCMS-200 ultrasonic cure monitoring system from Micromet Instruments utilizes measurements of the ultrasonic sound speed to monitor changes in the viscosity, rigidity of composites. 

Microban International, 1221 Avenue of the Americas, 24th Floor, New York, NY 10020, USA tel +1-212-332-8730 fax +1-212-332-8739 Micromet Instruments Inc, 7 Wells Avenue, Newton Centre, MA 02159, USA ... 

Figure 14. Micrometer positioning device for the DAC in an FTIR Nicolet instrument. The ample available space permits inclusion of the micrometer instrument, the heater and thermocouple leads with ease.

Aspects of common DEA techniques are presented in the following paragraphs, with emphasis on the instrumentation that is likely to be used in a typical thermal analysis laboratory examples are Novocontrol Spectrometers (BDS), TA Instruments (DEA 2970, although the production of this instrument has been discontinued), and Polymer Laboratories (DETA, this instrument is not available any more either). Dielectrometers (Micromet Instruments, now owned by Netzsch), used for in-process cure monitoring of thermosets, operate on similar principles. Features of the sensitive thermally stimulated current technique, and its comparison to DEA, are also discussed. 

The nebulization concept has been known for many years and is commonly used in hair and paint spays and similar devices. Greater control is needed to introduce a sample to an ICP instrument. For example, if the highest sensitivities of detection are to be maintained, most of the sample solution should enter the flame and not be lost beforehand. The range of droplet sizes should be as small as possible, preferably on the order of a few micrometers in diameter. Large droplets contain a lot of solvent that, if evaporated inside the plasma itself, leads to instability in the flame, with concomitant variations in instrument sensitivity. Sometimes the flame can even be snuffed out by the amount of solvent present because of interference with the basic mechanism of flame propagation. For these reasons, nebulizers for use in ICP mass spectrometry usually combine a means of desolvating the initial spray of droplets so that they shrink to a smaller, more uniform size or sometimes even into small particles of solid matter (particulates). 

Basically, the optical method uses equipment such as alignment telescopes, jig transits, and sight levels. Instruments with built-in optical micrometers for measuring displacements from a referenced line of sight enable an accurate determination of target movements, which are mounted on the machine. 

Fein-messen, n. precision measurement, -mes-ser, m. micrometer vernier, -messgerat, n. precision measuring instrument, -messlehre, /. micrometer caliper or gage, -mess-... 

The solvent reservoir is a storage container made of a saterial resistant to chemical attack by the mobile diase. In its simplest fora a glass jug, solvent bottle or Erlenmeyer flask with a cap and a flexible hose connection to the pump is adequate. The PTFE connecting hose is terminated on the solvent side with a 2 micrometer pore size filter to prevent suspended particle matter from reaching the pump. In more sophisticated instruments the solvent reservoir may also be Cjquipped for solvent degassing, as... 

The nanometer- to micrometer-scale dimensions of supramolecular assemblies present many challenges to rigorous compositional and structural characterization. Development of adequate structure-property relationships for these complex hierarchical systems will require improved measurement methods and techniques. The following areas constitute critical thrusts in instrument development. 

Infrared (IR) spectroscopy, especially when measured by means of the Fourier transform method (FTIR), is another powerful technique for the physical characterization of pharmaceutical solids [17]. In the IR method, the vibrational modes of a molecule are used to deduce structural information. When studied in the solid, these same vibrations normally are affected by the nature of the structural details of the analyte, thus yielding information useful to the formulation scientist. The FTIR spectra are often used to evaluate the type of polymorphism existing in a drug substance, and they can be very useful in studies of the water contained within a hydrate species. With modem instrumentation, it is straightforward to obtain FTIR spectra of micrometer-sized particles through the use of a microscope fitted with suitable optics. 

Several advantages offered by CE, such as a high efficiency, rapid method development, simple instrumentation, and low sample consumption, are the main reasons for its success in a variety of fields. UV-VIS spectrophotometry is probably the most widely used detection technique with CE because of the simplicity of the on-line configuration. However, its sensitivity, directly related to the optical path length afforded by the I.D. of capillaries, which is in the micrometer range, is low, and it remains the major bottleneck of this technique (see... 

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