Mid- and near-infrared (IR) spectroscopy has been used to study the curing of a bisphenol-A based epoxy resin (EPON-828) with tetrafunctional agent, viz., meta-phenylenediamine (MPDA). Three different cure cycles were in study. Primary amine functionality was observed react relatively rapidly; none remained after for 2 h at 75°C. Secondary exhausted rich samples subjected standard cycle (2 75°C followed by 125°C). In stoichiometric amount or higher MPDA, complete reaction secondary groups...

Infrared spectra of several 1,3-dicarbonyl compounds from different organic chemical clauses have been recorded. Assignments characteristic enol frequencies made, and group frequency ranges developed. In most cases, the are reasonably narrow considering great changes in overall structure examples studied. The affects to a significant degree absorption certain modes.

The design of a reflecting microscope for FT-IR microspectromatry is described. employs infinity-corrected optics and novel dual confocal aperturing configuration. performance the discussed relative to stray light rejection use differential interference contrast with IR microspectroscopy.

Beam condensers are economical accessories for infrared (IR) spectrometers and can very effectively reduce IR detection limits to the nanogram range (and below). Sample presentation beam condenser has commonly been microdisk, a miniature pellet pressed from mixture of analyte an alkali halide salt. The sample must be ground prior pressing pellet. For some small samples, such as paint chips, fibers, polymers in general, grinding is not practical; however, frequently these samples too thick...

A new point sensor for identifying chemical weapons of mass destruction and other hazardous materials based on Fourier transform infrared (FT-IR) spectroscopy is presented. The a portable, fully functional FT-IR system that features miniaturized Michelson interferometer, an integrated diamond attenuated total reflection (ATR) sample interface, embedded on-board computer. Samples are identified by automated search algorithm compares their spectra to digitized databases include reference nerve...

Abstract Die Wechselwirkungen zwischen Strömungsbedingungen, Stofftransportgeschwindigkeit und Abtragsgeschwindigkeit in Zweiphasenströmungen werden bei der Simulation von Erosionskorrosion untersucht. Geschwindigkeit die Beladung Strömung variiert. Zur Bestimmung dient Grenzstromtechnik. Untersuchungen im Redoxsystem Kaliumhexacyanoferrat(II)/Kaliumhexacyanoferrat(III) an einer glatten Platinelektrode durchgeführt. wird gravimetrisch den Stählen St 38 X8 CrNiTi18. 10 wäßrigen...

IR spectroscopy is a broadly applicable technique for the identification of covalent materials. Recent advances in instrumentation have made Fourier Transform infrared (FT-IR) available field characterization suspect Presently, this deployed and used potential chemical hazards. This discussion concerns work towards expanding analytical utility field-based FT-IR spectrometry biological threats. Two classes materials were studied: biologically produced toxins which non-peptide nature peptide...

Emerging chemical threats to homeland security challenge the specificity of sensor-based detectors. As number chemicals detect increases, false alarm rates these systems tend increase and usefulness detector in real world situations declines. The infrared (IR) absorption spectrum a material is physical constant highly specific for molecule interest. For many years, IR spectra have been used by chemists identify unknowns based on comparison with known materials determine presence functional...

Abstract What is combinatorial chemistry? Combinatorial chemistry quickly becoming a very popular technique for organic synthesis in the pharmaceutical and biotechnology fields. Basically, methods allow one to obtain thousands of derivatives chemical compounds quick efficient manner. The method begins when molecule interest attached resin beads. Once attached, number reactions can be run on beads split up into several subsets, different each subsets. Because are solid phase, it extremely...

Abstract

Abstract The surface of printed paper has been examined through a fully automated attenuated total reflection (ATR) mapping technique. Automated z-axis control was utilized to bring the sample into contact with ATR objective in reproducible manner and an integrated stage used position sample. A force sensing device, Contact Alert, ensure optimal between internal element Global manipulations resultant data revealed compositional differences attributed ink, carbonate cellulose distributions....

The feasibility of using IR mapping microspectroscopy to locate and identify a neuroanatomical probe in brain tissue has been demonstrated. Frequency specific maps were generated from latex nanosphere injection site tissue. 2240 cm<SUP>-1</SUP> vCN absorption band, attributable the latex, was used as an analytical band.

A NIR Raman accessory has been designed for use with a Perkin-Elmer Model 1700 Fourier Transform Spectrometer. The design does not interfere application of the instrument normal mid-infrared spectroscopy. In order to demonstrate performance, number different types samples and analytical problems have considered. These include structure-spectra correlations, pharmaceuticals, polymers, highly colored fluorescent materials, sampling.