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Reflection, attenuated total

The experimental apparatus consists of a gas flow system with a four-port valve, a multi-reflection Attenuated Total Reflection (ATR) accessory (Pike Technologies), and a custom reactor manifold mounted to the ATR top plate, shown in Fig. 45.1. The ATR reactor manifold consists of (i) a Cap2 window for UV irradiation, (ii) an inlet and outlet port, and (iii) an injection port for the liquid phase reactant. [Pg.406]

Internal reflectance (attenuated total reflectance ATR ). The internal reflectance or, more usually, attenuated total reflectance (ATR), technique depends on the total reflectance of an IR beam at the internal face of an IR-transparent crystal of high IR refractive index, as shown in Figure 2.38. Medium 1 is a prism of such a material (for example, Si, Ge or KRS-5 [thallous bromide- iodide]), medium 2 is a thin coating of a metal (Au, Pt, Fe) which forms the working electrode and medium 3 is the electrolyte. The... [Pg.96]

Infrared spectra of zeolitic samples can be measured in several different modes. These include transmission, diffuse reflectance, attenuated total internal reflection (ATR) and emission. Transmission and diffuse reflectance are by far the most widely used of these techniques. In the transmission mode, the sample is placed directly in the infrared beam of the instrument and the light passing through or transmitted is measured by the detector. This transmitted signal (T) is ratioed to the open beam (no sample) signal (To) to get the transmission spectrum of the sample. The transmission spectrum is converted to an absorbance spectrum ... [Pg.112]

FT Spectrometers FT spectrometers (Figure 3) differ from scanning spectrometers by the fact that the recorded signal is an interferogram [14] (see Chapter 6.2). They can be coupled to a microscope or macrochamber with an FPA detector. FT chemical imaging systems (CISs) are available for Raman, NIR, and IR spectroscopy. However, they can only be considered as research instruments. For example, most IR imaging systems are FT spectrometers coupled to microscopes. This type of spectrometer allows the acquisition of spectra in reflection, attenuated total reflection (ATR), or transmission mode. [Pg.414]

Aspartic peptidases, 365 Atmospheric pressure chemical ionization (APCI), used with LC/MS ATR-FTIR. see Attenuated total reflection Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), trans fatty acids, 505-511 Autoxidation. see also Oxidation discussed, 535 of lipids, 558, 627 prevention of, 558... [Pg.757]

The first HWGs confined light to their core either by total internal reflection (attenuated total reflection guides) or by reflection off a metallic surface (leaky guides) as discussed in Sect. 2.3.1. The latest generation of HWGs is based on PBG materials as discussed in Sect. 2.3.2. [Pg.142]

Diffuse Reflectance, Attenuated Total Reflection or Multiple Internal Reflection, Photoacoustic (PAS), Photothemal Beam Deflection, Specular Reflection Absorption, and forensic applications with the diamond cell and the Fourier transform infrared (FTIR) microscope. In museum laboratories, FTIR applications have been used for problems of identification and degradation in art and archeology. (14)... [Pg.240]

Bertolucci, Jantzef, and Chamberlain (8) report briefly on their work using single-reflection, attenuated, total-reflection, infrared spectroscopy to study the mechanism of adsorption on hydroxy-apatite crystals of citric acid, tartaric acid, sodium citrate, oxytetracycline hydrochloride, and glycine. This work has been of interest to many chemists, but it also has particular pertinency to current research on dental adhesives and the effect of pretreatment of the tooth cavity wall. [Pg.14]

FTIR-ATR Fourier transform infrared reflection-attenuated total reflection... [Pg.9]

Changes in wheat carbohydrate chemistry due to chemical enzymatic degradation were measured on a macro scale by internal reflection (attenuated total reflection ATR) FT-IR spectroscopy from a spot size of 250 X 250 gm [51]. In this study, the absorption bands of sucrose, fructose, glucose, arabinose and galactose were identified, and spectra included for mahogany, huckleberry and oak, as well as for cellulose and cellophane. Both, principal component analysis (PCA) and plotting of PCI versus PC2 enabled distinctions to be made between filter paper, cello-... [Pg.246]

Total Internal Reflection (Attenuated Total Reflectance)... [Pg.117]

Measurement in the reflectance mode using either external specular reflection, internal reflection [attenuated total reflection (ATR)] or diffuse reflection... [Pg.37]

If medium 1 is absorbing, the evanescent field wiU be absorbed and less intensity can be reflected (attenuated total reflection (ATR)). An ATR spectrum is similar to the conventional absorption spectrum except for the band intensities at longer wavelengths. At longer wavelengths the evanescent field penetrates ever deeper into the sample, equivalent to an increasing sample thickness. Sometimes an empirical so-called ATR correction is appHed in order to compensate across the spectrum for the linear wavelength increase in Eq. (10) ... [Pg.76]

In principle, the sensor constructions rely on five basic sensing schemes transmission, reflection, grazing angle reflection, attenuated total reflection (ATR), and a variant of the ATR effect known as the fibre-evanescent wave sensor (FEWS) (Melting Thomson, 2002). The investigations described in chapters 3 and 4 are based on the use of the ATR technique, focusing on its advantageous properties, esp edally in terms of mechanical robustness. [Pg.495]

In internal reflection, at angles of incidence larger than the critical angle, electromagnetic radiation is totally reflected (attenuated total reflectance, ATR. see Section 16.2.2.4 and Fig. 5). This special ca.se is very important in analysis for two approaches. First, simple transportation of radiation within the fiber (or a waveguide). Second, in total reflection, an evane.scent field appears in which the electrical field vector decays exponentially in the optically less dense medium. Every change within the medium with lower refractive index influences the field vector coupled to the field in the optically denser medium. Therefore, the totally reflected radiation contains information about effects on the other side of the phase boundary (the medium with lower refractive index) [20], [144]. Various principles to interogate this effect are known and used in evanescent field sensors. [Pg.448]

A small-size target specimen will often need to be removed from a matrix in which it is buried by using a knife, scalpel, or needle in an appropriate and safe manner, depending on the conditions surrounding it. If the target specimen is covered by a layer of some other material this may need to be scraped off Infrared microscopic measurements are utilized in many areas of study. In order to satisfy the various needs, in addition to straightforward transmission measurements, various types of reflection measurements such as specular reflection, attenuated total reflection (ATR), and transmission-reflection measurements (described later) can be performed with an infrared microscope designed for such purposes. [Pg.224]

Owing to these improvements, infrared spectroscopy has undergone a marked development in the last few years because of the possibility of adapting new accessories to the spectrometers and, therefore, of analysing samples whose infrared spectrum was impossible to obtain some years ago. Among these accessories are those which can measure specular and diffuse reflection, attenuated total reflectance and microscopes. One area in which the technique has improved dramatically is forensic analysis. [Pg.603]


See other pages where Reflection, attenuated total is mentioned: [Pg.235]    [Pg.121]    [Pg.198]    [Pg.139]    [Pg.733]    [Pg.3]    [Pg.235]    [Pg.133]    [Pg.787]    [Pg.322]    [Pg.61]   
See also in sourсe #XX -- [ Pg.317 ]




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ATR-FTIR (attenuated total reflectance-Fourier transform

ATTENUATED TOTAL

Albumin attenuated total reflection

Applications Attenuated total internal reflectance

Attenuated Total Infrared Internal Reflectance (ATR) Spectroscopy (Spectra-Tech)

Attenuated Total Reflectance spectra

Attenuated Total Reflectance spectra of Nafion

Attenuated Total Reflection (ATR) Mode

Attenuated Total Reflection (ATR) Technique

Attenuated Total Reflection Infrared Spectrometry (ATR)

Attenuated Total Reflection crystal

Attenuated Total Reflection probes

Attenuated Total Reflection synthesis

Attenuated Total Reflection-FTIR

Attenuated multiple total internal reflection

Attenuated multiple total internal reflection technique

Attenuated total internal reflectance

Attenuated total internal reflection (ATR

Attenuated total internal reflection infrared

Attenuated total internal reflection infrared spectroscopy

Attenuated total reflectance

Attenuated total reflectance

Attenuated total reflectance (ATR

Attenuated total reflectance Attenuation

Attenuated total reflectance Attenuation

Attenuated total reflectance FTIR polymers

Attenuated total reflectance Fourier

Attenuated total reflectance Fourier analysis

Attenuated total reflectance Fourier method

Attenuated total reflectance Fourier transform

Attenuated total reflectance Fourier transform infrared

Attenuated total reflectance Fourier transform spectroscopy

Attenuated total reflectance Fourier transform-infrared spectroscopy

Attenuated total reflectance Fourier transformation infrared spectroscopy

Attenuated total reflectance Fourier transformed

Attenuated total reflectance Fourier transformed infrared spectroscopy

Attenuated total reflectance Fourier-transformation infrared

Attenuated total reflectance accessory

Attenuated total reflectance chemical structures

Attenuated total reflectance crystals

Attenuated total reflectance fourier transform infrared spectrometry

Attenuated total reflectance infrared

Attenuated total reflectance infrared absorption

Attenuated total reflectance infrared spectra

Attenuated total reflectance infrared spectrometry

Attenuated total reflectance infrared spectroscopy

Attenuated total reflectance infrared surface species, study

Attenuated total reflectance length

Attenuated total reflectance mid-infrared

Attenuated total reflectance principles

Attenuated total reflectance sampling depth

Attenuated total reflectance spectroscopy

Attenuated total reflectance surface-enhanced

Attenuated total reflectance surface-enhanced infrared absorption spectroscopy

Attenuated total reflectance technique

Attenuated total reflectance, analysis

Attenuated total reflectance, interfacial

Attenuated total reflectance, sample

Attenuated total reflectance-FTIR

Attenuated total reflectance-Fourier spectroscopy

Attenuated total reflection Fourier

Attenuated total reflection Fourier transform infrared

Attenuated total reflection Fourier transform infrared spectroscopy , polymer

Attenuated total reflection IR

Attenuated total reflection Subject

Attenuated total reflection adsorption

Attenuated total reflection cell design

Attenuated total reflection configurations

Attenuated total reflection correction

Attenuated total reflection dichroism

Attenuated total reflection fluids

Attenuated total reflection fundamentals

Attenuated total reflection infrared

Attenuated total reflection infrared spectroscopy

Attenuated total reflection instrumentation

Attenuated total reflection methods

Attenuated total reflection microspectroscopy

Attenuated total reflection mode

Attenuated total reflection principle

Attenuated total reflection protein layer

Attenuated total reflection protein solutions

Attenuated total reflection protein studies

Attenuated total reflection reaction

Attenuated total reflection sample contact

Attenuated total reflection sampling technique

Attenuated total reflection solid-liquid interface

Attenuated total reflection specialized techniques

Attenuated total reflection spectrometry

Attenuated total reflection spectroscopy

Attenuated total reflection spectroscopy (ATR

Attenuated total reflection spectroscopy lipids

Attenuated total reflection spectroscopy polarization

Attenuated total reflection spectroscopy principle

Attenuated total reflection spectroscopy sample cells

Attenuated total reflection spectrum

Attenuated total reflection surface plasmon waves

Attenuated total reflection technique

Attenuated total reflection transmission

Attenuated total reflection, ATR

Attenuated total reflection-Fourier transform

Attenuated total reflection-Fourier transform infrared spectrometer

Attenuated total reflection-Fourier transform infrared spectroscopy

Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR

Attenuated total reflection-Fourier transform spectroscopy)

Attenuated total-reflection waveguide

Attenuation total reflection

Attenuation total reflection

Attenuator attenuated total reflection

Attenuator attenuated total reflection

Circular Attenuated Total Reflection (CATR)

Coupled attenuated total reflection

Epoxy attenuated total reflection spectroscopy

FTIR, attenuated total reflectance data collection

Flowing attenuated total reflection

Forensic attenuated total reflection

Horizontal attenuated total reflectance

Horizontal attenuated total reflectance HATR)

Horizontal attenuated total reflection

In situ attenuated total reflectance infrared

In situ attenuated total reflectance infrared spectroscopy

Infrared spectrophotometry attenuated total reflectance

Infrared spectroscopy attenuated total reflectance Fourier

Infrared spectroscopy attenuated total reflection technique

Instruments attenuated total reflection

Pharmaceutical attenuated total reflection

Polarized attenuated total reflection infrared spectroscopy

Poly attenuated total reflectance Fourier

Polymer attenuated total reflection

Protein attenuated total reflection, polymer

Reflectivity total

Scanning Electrochemical Microscopy-Attenuated Total Reflection Spectroscopy

Single-wavelength attenuated total reflection-based devices

Surfaces, studies attenuated total internal reflection

Time-resolved attenuated total reflectance

Time-resolved attenuated total reflectance spectroscopy

Total internal reflection, attenuated

Total reflection

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