FT spectrophotometer

Infrared spectra of polydicyclopentadiene were recorded on a Nicolet lOMX(FT) spectrophotometer. Polymer samples for this analysis were films prepared by evaporating a thin layer of polymer solution. NMR spectra of linear PDCPD were obtained in CDCI3 using a Brucker (300 MHz) spectrophotometer with TMS as internal standard. 

Two common detectors, which also are independent instruments, are Fourier transform infrared spectrophotometers (FT-IR) and mass spectrometers (MS). In GC-FT-IR, effluent from the column flows through an optical cell constructed... 

Co concentration was determined by spectrophotometer (Varian Cary 500) at 692 nm wave length, with the sample diluted with a 9 mol/L concentrated HCl solution. NO content in gas phase was obtained by an on-line Fourier transform infrared spectrometer (Nicolet E.S.P. 460 FT-IR) equipped with a gas cell and a quantitative package, Quant Pad. 

FT-IR spectra were recorded at RT on a Perkin-Elmer 1760-X spectrophotometer equipped with a cryodetector, at a resolution of 2 cm-" (number of scans -100). In the 1070-960 cm- region, band integration and curve fitting were carried out by Curve fit, in Spectra Calc. (Galactic Industries Co.). Powdered materials were pelleted in self-supporting discs of 25-50 mg cm-2 and 0.1-0.2 mm thick, placed in an IR cell allowing thermal treatments in vacuo or in a controlled atmosphere. 

In order to follow progress of elimination, reactions were also performed on thin films in a special sealed glass cell which permitted in situ monitoring of the electronic or infrared spectra at room temperature (23°C). Typically, the infrared or electronic spectrum of the pristine precursor polymer film was obtained and then bromide vapor was introduced into the reaction vessel. In situ FTIR spectra in the 250-4000 cm-- - region were recorded every 90 sec with a Digilab Model FTS-14 spectrometer and optical absorption spectra in the 185-3200 nm (0.39-6.70 eV) range were recorded every 15 min with a Perkin-Elmer Model Lambda 9 UV-vis-NIR spectrophotometer. The reactions were continued until no visible changes were detected in the spectra. 

Spectra of solution cast films of the hydrogenated NBR were recorded on a Nicolet 520 FT-IR spectrophotometer. The final degree of olefin conversion was confirmed by infrared analysis.9... 

Spectra were obtained using a Digilab FTS-15E Fourier Transform Spectrophotometer. A NaCl crystal mounted in a heated cell (Model 018-5322 Foxboro/Analabs, N. Haven, Ct.) was placed in the infrared beam and the chamber allowed to purge for several minutes while the cell was brought to the desired temperature. The temperature of the cell was controlled using a DuPont 900 Differential Thermal Analyzer interfaced to the spectrometer cell. A chlorobenzene solution (ca. 10 by wt.) of the sample was then applied to the crystal using cotton tipped wood splint. 

Samples were characterized by FTIR spectroscopy with a Perkin Elmer (Spectrum BX) spectrometer using KBr pressed disks as matrices. The DRIFT experiments were carried out with a Broker IFS 55 spectrometer equipped with a Thermo Spectra Tech reacting cell. UV-vis Diffuse Reflectance spectra were recorded on a Perkin Elmer Lambda 45 spectrophotometer equipped with a diffuse reflectance attachment. Raman spectra were collected with Perkin Elmer system 2000 NIR FT-Raman using as excitation radiation the 5th harmonic of a diode pumped Nd YAG laser (1065 nm). 

The infrared spectrum of pseudoephedrine hydrochloride is shown in Figure 1. It was obtained as a 0.2% dispersion of pseudoephedrine hydrochloride in KBr with a Nicolet Model 7199 FT-IR spectrophotometer.2 Table I gives the infrared assignments consistent with the structure of pseudoephedrine hydrochloride. 

Figure la. The optical arrangements of an FT-IR Spectrophotometer with reflectance attachments in the sample chamber for electrochemical experiments. (Reproduced with permission from Ref. 9. Copyright 1984 Elsevier.)... 

Equipment. All melting points were determined with a Mel-Temp apparatus from Laboratory Devices and are uncorrected. Gas chromatography was carried out on either a Varian Aerograph 700 or Hewlett-Packard 5880 chromatograph. Beckman IR-9 and Perkin Elmer FT-1800 spectrophotometers were used for the determination of mid-IR spectra. All NMR spectra were obtained using an IBM NR-80 FT spectrometer. Elemental analyses were determined for all new monomers and polymers by Micro-Tech Laboratories, Inc. of Skokie,... 

Infrared spectra were obtained with a Perkin-Elmer 1800 and a Nicolet Magna-IR 750 FTIR spectrophotometer, and the absorption frequencies are reported in wave numbers (cm ). NMR spectra were obtained with a BZH-300 and a CA-F-300 Bruker FT NMR 300MHz spectrometer, and a Varian EM390 90-MHz spectrometer. All chemical shifts are reported in parts per million downfield (positive) of the standard. H-NMR and C-NMR chemical shifts are reported relative to internal tetramethylsilane, while T-NMR chemical shifts are reported relative to internal fluorotrichloromethane. Unless specified, Rf values were obtained from silica gel thin-layer chromatography developed with a mixture of 1.5 ml of methylene chloride and three drops of acetone. Melting points were determined with an Electrothermal melting-point apparatus without correction. Elemental analyses were performed by Galbraith Laboratories, Inc., Knoxville, Tern. 

PS118, PS160, PS340, PS463, PS537, and PS732) were obtained from Petrarch Systems, Inc. For the IR spectra a Nicolet MX-10 FT-IR spectrometer was used at a resolution of 1 cm". The UV spectra were measured on a Model DMS 90 Varian Associates UV-Visible spectrophotometer which was connected to an Apple 11+ desktop computer, equipped with an in-house modified Varian Associates software package. Other experimental details are described elsewhere(3). 

A Digilab FTIR spectrophotometer (Model FTS-60) was used to obtain IR spectra of samples before and after extractions. Standard KBr pellets containing 1% by weight sample were used. 

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