Wide Spectral Range

The variation of intensity with wavelength depends only on the critical wavelength (k ), the vertical scale of intensity being simply defined by the electron current and energy. The value of is given by the following formula  

Laboratory for Utilization of Electromagnetic Radiation. LURE-CNRS, University Paris-Sud, Bat. 209C, 91407 ORSAY Cedex. FRANCE. 

Taking a magnetic field of 1.2 T, a wavelength of = 1 A can be achieved with an electron energy E = 3.94 GeV. The shape of the spectrum indicates that, in such a case, a radiation extending from the X-ray region to the far infra-red can be obtained. 

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Dozens of compounds have been used in in vivo fluonne NMR and MRI studies, chosen more for their commercial availability and established biochemistry than for ease of fluonne signal detection [244] Among the more common of these are halothane and other fluormated anesthetics [245, 246], fluorodeoxyglucose [242 243], and perfluormated synthetic blood substitutes, such as Fluosol [246], a mixture of perfluorotnpropylamine and perfluorodecahn Results have been Imut-ed by chemical shift effects (multiple signals spread over a wide spectral range) and long acquisition times... 

The closed cycle of interconversions occurs on an ultrafast time scale. Femtosecond studies (95CPL35) of the ESIPT rearrangement of 347 (R = Me) (commercial name Tinuvin-P) carried out over a wide spectral range... 

Normally, time-resolved FT-IR spectroscopy (TRS FT-IR) possesses the same data characteristics. In a typical TRS FT-IR experiment, interferograms are assembled for a specific delay time after the photolysis pulse, and the data produced are normally finer-grained in frequency than in time. This type of experiment is complementary to experiments with fine-grained time information. It is particularly useful where a wide spectral range is necessary and works reasonably well for highly reproducible events which occur on relatively long timescales (fractions of seconds) (83). It is also an appealing system for use on shorter timescales, and it has... 

Using FLAMES we observed, 45 turnoff stars, 7 giant stars with GIRAFFE (LR2 from 396.4 to 456.7 nm, R 6400 and H15 from 660.6 to 696.5 nm, R 19300). At the same time, 3 stars known as blue stragglers ([1]) were observed by UVES-link R = 47000, and a 200 nm wide spectral range centered around 580 nm. 

So the function of special optical fibres for sensing is to produce a sensitive response to changes in the fibre surroundings. Such requirements on optical hardware as durability to the analyte, transparency (i.e. minimum optical losses) in a wide spectral range and common availability should be pointed out. Related to the these requirements, the choice of the fibre material as well as of the fibre coating and fibre structure belong to fundamental tasks in the design of fibre-optic sensors. 

Fourier transform infrared spectroscopy spectrometers can cover wide spectral ranges with a single scan in a relatively short scan time, thereby permitting the possibility of kinetic time-resolved measurements. 

Infrared spectroscopy is the workhorse in this field, because it can quickly provide dynamical details, discriminate between different cluster sizes and phases [40], and sample a wide spectral range. It often yields valuable feedback for quantum chemical calculations. In contrast to some action spectroscopy techniques, IR absorption spectroscopy is not intrinsically size-selective. All cluster sizes generated in the expansion are observed together, and indirect methods of size assignment are needed. 

Laser radiation can be obtained nowadays over a wide spectral range from the ultraviolet to the far infrared region, covering the range of optical spectroscopy. Fignre 2.4 shows schematically the spectral zones covered by different types of lasers. Although there are some specific regions in which direct laser action is not available. 

Recently, cyanine fluorochromes covering a wide spectral range have become available for immunofluorescence (13,14). The red-emitting fluoro-chrome Cyanine 3.18, which was shown to give a significantly brighter image than TRITC, lissamine rhodamine, Texas Red, or fluorescein under specific conditions of microscopy (7), provides a useful alternative to the rhodamines. Other useful substitutes for the rhodamines include the BODIPY TR and TMR, and Alexa 568 and 594 fluorochromes. The latter are newly introduced and appear to offer superior photostability. 

V at 100 MC/sec compared with 10 kV in Kerr cells) and they transmit over a wide spectral range (2500-12000 A). When designed as travelling wave modulators, they can be used even up to micro-wave modulation frequencies... 

Problems like overlapping and interfering of fluorophores is overcome by the BioView sensor, which offers a comprehensive monitoring of the wide spectral range. Multivariate calibration models (e.g., partially least squares (PLS), principal component analysis (PCA), and neuronal networks) are used to filter information out of the huge data base, to combine different regions in the matrix, and to correlate different bioprocess variables with the courses of fluorescence intensities. 

Time-resolved luminescence spectroscopy may be extremely effective in minerals, many of which contain a large amount of emission centers simultaneously. With the steady state technique only the mostly intensive centers are detected, while the weaker ones remain unnoticed. Fluorescence in minerals is observed over time range of nanoseconds to milliseconds (Table 1.3) and this property was used in our research. Thus our main improvement is laser-induced time-resolved spectroscopy in the wide spectral range from 270 to 1,500 nm, which enables us to reveal new luminescence centers in minerals previously hidden by more intensive centers. 

The deposition in Ref 11, from an alkaline thiosulphate bath, was reported in the context of a general description of deposition of various materials by CD, and only a little characterization was reported. X-ray diffraction showed some Ag2S peaks. Optical spectroscopy showed a gradual decrease in transmission over a wide spectral range, and it would be difficult to extract a reliable value for the bandgap from the spectrum. 

Covering a wide spectral range, solar radiation is divided roughly into two equal energy portions—the ultraviolet and visible in the 0.25- to 0.7-micron wave lengths, and the infrared out to about 2 or 2.5 microns. 

The applications of inelastic tunneling presented in Sec. V point up both the strong and weak points of this spectroscopy. Inelastic electron tunneling is sensitive, has good resolution, does not require large capital investment, has a wide spectral range, is sensitive to all surface vibrations, and can be used on oxide and supported metal catalysts. However, a counter-electrode must be used, single crystal metal surfaces cannot be used, and spectra must be run at low temperatures. 

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