Bruker Fourier transform

FTIR spectra were measined with a IFS-113v Bruker Fourier-transform IR spectrometer at 300 K. In Fig. 2 experimental FTIR transmittance spectrum of... 

In order to study the formation of interfacial metal phosphate layers, the untreated bare CRS panels were mechanically polished to a mirror finish and used as coating substrates. The ISPC was applied on mirror-finished CRS and cured at 163°C for 15 min. The polymer layer on each panel was removed without damaging the interface by soaking the panel in tetrahydrofuran solvent. The interfacial metal phosphate layer was rinsed with deionized water, dried, and characterized by a Bruker Fourier transform infrared (FTIR) spectrophotometer model Vector 22 equipped with a Spectra Tech FT-80 grazing angle accessory. 

H-NMR studies were performed on a Bruker MSL-400 spectrometer operating in the Fourier transform mode, using a static multinuclei probehead operating at 400.13 MEtz. A pulse length of 1 iis is used for the 90° flip angle and the repetition time used (1 second) is longer than five times Tjz ( H) of the analyzed samples. 

Fourier Transform (FT) Ranun spectroscopy (Model RFS 100/S, BRUKER Co.) using ND YAG laser was used to analyze the products on their structure electronic and vibration properties. The morphology of CNTs was observed by scanning dartron microscopy (SEM, Model S-4200, Hitach Co.) and transmission electron microscope (TEM, Modd JEOL 2000FX-ASID/EDS, Philips Co.). 

The matrix obtained after the F Fourier transformation and rearrangement of the data set contains a number of spectra. If we look down the columns of these spectra parallel to h, we can see the variation of signal intensities with different evolution periods. Subdivision of the data matrix parallel to gives columns of data containing both the real and the imaginary parts of each spectrum. An equal number of zeros is now added and the data sets subjected to Fourier transformation along I,. This Fourier transformation may be either a Redfield transform, if the h data are acquired alternately (as on the Bruker instruments), or a complex Fourier transform, if the <2 data are collected as simultaneous A and B quadrature pairs (as on the Varian instruments). Window multiplication for may be with the same function as that employed for (e.g., in COSY), or it may be with a different function (e.g., in 2D /-resolved or heteronuclear-shift-correlation experiments). 

NMR spectroscopy was performed with a Bruker AC-300 spectrometer at 75 MHz in the Fourier-transform mode, with proton decoupling at 30 C, using 5 mm tubes and D2O as solvent. The spectral width was 200 ppm. Chemical shifts are expressed in ppm relative to the resonance of external DSS (sodiiun 4,4-dimethyl-4-silapentane-1 -sulfonate). 

NMR spectra were obtained in continuous wave mode on a Varian T-60, and in the pulsed Fourier transform mode on a Varian HR-220 with Nicolet TT-100 Fourier transform accessory, a Nicolet NT-300 wide bore system, and a Bruker WM-500. 13C T1 data were obtained... 

Fig. 8. The 195Pt-NMR spectra of a DMF solution of [Pt2(en)3(PRI)2(N02) (N03)](N03)2 0.5 H20 (11) at 5°C, acquired on a Bruker WM-250 spectrometer operating at 53.6 MHz. (a) Power spectrum of the Fourier transform of a 1 K FID accumulated with a 5-jjls pulse width, 100-kHz spectral width, and 2000 K transients, (b and c) Normal Fourier transforms of 1 K FIDs accumulated with 10-fis pulsewidths, 42-kHz spectral width, and 64 K transients per spectrum. All FIDs were treated with 400-Hz line broadening functions to suppress noise (58).

Fig. 4.50. Illustration of the effect of Fourier transformation. The longer the detection interval the more accurate the result wiU be. By courtesy of Bruker Daltonik, Bremen.

Proton decoupled natural abundance Fourier transform NMR spectra were obtained on a Bruker HX270 at... 

The proton noise-decoupled 13c-nmr spectra were obtained on a Bruker WH-90 Fourier transform spectrometer operating at 22.63 MHz. The other spectrometer systems used were a Bruker Model HFX-90 and a Varian XL-100. Tetramethylsilane (TMS) was used as internal reference, and all chemical shifts are reported downfield from TMS. Field-frequency stabilization was maintained by deuterium lock on external or internal perdeuterated nitromethane. Quantitative spectral intensities were obtained by gated decoupling and a pulse delay of 10 seconds. Accumulation of 1000 pulses with phase alternating pulse sequence was generally used. For "relative" spectral intensities no pulse delay was used, and accumulation of 200 pulses was found to give adequate signal-to-noise ratios for quantitative data collection. 

NMR spectra in D20 were recorded on a Bruker WM-360 NMR spectrometer. IR spectra were recorded neat with liquids or as fluorolube mulls with solids using a Nicolet 20DXB Fourier Transform Infrared Spectrophotometer. 

Spectra. P-31 and H-l NMR spectra were obtained with a Bruker HX90 Fourier transform spectrometer using spinning 10-mm tubes, a deuterium lock from the deuterated solvent, and external 85% H3P04 as the reference. IR spectra were obtained using a Perkin-Elmer Model 337 grating spectrometer that covered the range from 4000 cm-1 to 400 cm-1. 

U.K.), with a normal sweep width of 1000 Hz and sweep time of 500 s. Fourier transform PMR spectra were recorded using a Bruker WH 300 instrument (Bruker Instruments Inc., Manning Park, Billerica, MA 01821, USA) and methanol-d as solvent (NMR Ltd). 

Fourier transform (FT) IR spectroscopy is one of several nondispersive optical spectroscopies based on interferometry. A two-beam interferometer first proposed by Michelson is the basis of most modern FT-IR spectrometers, as exemplified by the schematic of the Bruker Equinox 55 spectrometer (Bruker Optik, Ettlingen, Germany) in Fig. 2. Simply described, the interferometer comprises a beam splitter and two mirrors. A collimated beam of IR energy is split at the beam splitter into equal halves. Half of the energy travels through the beam splitter to one of the mirrors, which is positioned at a fixed distance away from the beam splitter. The reflected beam travels perpendicular to the incident beam to a moving mirror. IR radiation reflects off the fixed and moving mirrors and recombines at the beam splitter. The recombined IR beam projects from the interferometer towards the detector on an optical path perpendicular to the source beam. 

Fig. 2 Block diagram of a Bruker Equinox 55 Fourier transform (FT) IR spectrometer...

The detector in capillary electrophoresis is the main component in nanoanalyses. Many detectors can be used for this purpose but the mass spectrometer is the best one due to its wide ranges and low concentration detection capabilities. In the last few years, time-of-flight-mass spectrometry (TOF-MS) instruments have come onto the market and are available in many sizes, but small instruments are preferred in NCE. Bruker (Billerica, MA) has provided a micro-TOF-MS-LC (2x2x4 feet) system for nanoanalyses. Bruker also introduced a Q-q-FTMS (Fourier transform mass spectrometer) for proteomics called the APEX-QE. It offers fast, dual quadrupoles, which provides the first stages followed by FTMS for the highest mass accuracy. It can be coupled to NCE and controlled by Bmker s ProteinScape work flow and warehousing... 

All broadband spectra were amplified by a low-noise preamplifier with a dynamic range > 1,000, and a broadband main amplifier. The amplified time-domain signal is digitized by a 20 MHz, 9 bit Bruker ADC with 128 K words of buffer memory, and Fourier transformed by a Bruker array processor (128 K word FFT in 8 sec). 

Total soil carbon was determinated by elemental analysis with an automatic analyzer (CHNS 932, Lego). FOURIER transform infrared spectroscopy (IFS 66, Bruker) was used for analysis of the main soil components clay, feldspar, silicate, carbonate, and sulfate. This method is based on the application of a multi-step iterative spectra exhaustion method in which the soil spectrum is decremented by a small fraction of the spectrum of the most probable component [HOBERT et al., 1993]. 

Bruker uses the command EM (exponential multiplication) to implement the exponential window function, so a typical processing sequence on the Bruker is EM followed by FT or simply EE (EF = EM + FT). Varian uses the general command wft (weighted Fourier transform) and allows you to set any of a number of weighting functions (lb for exponential multiplication, sb for sine bell, gf for Gaussian function, etc.). Executing wft applies the window function to the FID and then transforms it. 

The 500-MHz, H-n.m.r. spectra were recorded with a Bruker WM-500 spectrometer operating in the pulsed, Fourier-transform mode and equipped with a Bruker Aspect2000 computer having an 80k memory-capacity. The D resonance of D20 was used as the field-frequency lock-signal. The spectra were obtained by using a 90° pulse-width, and accumulated into 16k addresses with an acquisition time of... 

Si-NMR spectra were recorded on a Bruker VJM-250 (liquid) or a Bruker CXP-300 Fourier transform magic-angle-spinning (FT MAS) solid state spectrometer. Resonances are relative to tetramethyl-silane (TMS). Dynamics of the silicate solutions were studied by selective excitation techniques by using DANTE-type (131 pulse sequences. 

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