Circle accessory

Detailed experimental procedures for obtaining infrared spectra on humic and fulvic acids have been reported previously 9,22,25-26) and will be briefly described here. Infrared spectra were taken on the size-fractionated samples by using a Fourier transform infrared spectrometer (Mattson, Polaris) with a cooled Hg/Cd/Te detector. Dried humic and fulvic materials were studied by diffuse reflectance infrared spectroscopy (Spectra Tech DRIFT accessory) and reported in K-M units, as well as by transmission absorbance in a KBr pellet. Infrared absorption spectra were obtained directly on the aqueous size-fractioned concentrates with CIR (Spectra Tech CIRCLE accessory). Raman spectra were taken by using an argon ion laser (Spectra-Physics Model 2025-05), a triple-grating monochromator (Spex Triplemate Model 1877), and a photodiode array detector system (Princeton Applied Research Model 1420). All Raman and infrared spectra were taken at 2 cm resolution. 

Figure 15.11. Optical diagrams for (o) a CIRCLE accessory, and (b) a Tunnel ATR accessory (courtesy of Axiom Analytical, Inc.). Both accessories use a cylindrical IRE.

XR D-5 D/S. As the goniometer circle is horizontal, the table (Figure 9-5) can carry a fairly heavy load of instruments, samples, or accessories without risk of distorting the goniometer angle. Any value of 26 can be set reliably and quickly. Good performance is available at widely... 

Figure 22. (a) A fragment of the photosynthetic reaetion center with the three eomponents Speeial Pair (SP), Accessory Baeteriochlorophyll (BCh), and Bacteriopheophytin (BPh). Photoindueed electron transfer from SP to BPh takes place at a i lobal rate of (3 ps). (b) Prineiple of the modular mimetic approach. D and A are the donor and aeceptor porphyrins, respectively. M is an eleetron transfer mediator whose introduction between D and A can be realized via coordination of a metal center (solid circle) which will also bind the chelating part of the bisporphyrin spacer. 

In addition to the large circular chromosome that carries essential genes, bacteria also carry accessory genes in smaEer circles of double-stranded DNA known as plasmids. Plasmids range in size from 1000 to over 1 million base pairs. Plasmids are important in molecular diagnostics as they often encode pathogenic factors and antibiotic resistance. 

The instrument development cycle that began with a microscope accessory for an FT-IR spectrometer turned full circle with the production of a miniature interferometer accessory (the lUuminatIR ) for a research microscope. This latter development opened IMS to professional microscopists by adding a new, chemically selective dimension. Another small footprint-dedicated portable IMS used a diamond internal reflection element (IRE) to analyze solids or liquids on location. 

Fig. 190. Distribution of CRF and CGRP-immunoreactive climbing fibers in P7 mouse cerebellum (A-C) and in neurons of the inferior olive (D-F). CRF-immunoreactive climbing fibers and neurons are indicated by dots, CGRP-immunoreactive climbing fibers and neurons by open circles, a, b and c = subnuclei a, b and c of the medial accessory olive beta -i- group beta Cl, C2 = Crus I and II DAO = dorsal accessory olive dc = dorsal cap EGL.ML = external granular layer and molecular layer F = flocculus IGL = internal granular layer PF = paraflocculus MAO = medial accessory olive PO = principal olive PL = Purkinje cell layer. Redrawn from Yamano and Tohyama (1993).

Natoli Engineering Co., Inc., Tableting Accessories 28 Research Park Circle St. Charles, MO 63304, USA... 

A strip of conducting tissue (other than the A-V node) connects the atrium and ventricle. Impulses reaching the ventricle via the A-V node circle back to the atrium via the accessory pathway. Alternatively, the circuit may be reversed. 

Product Overview Brochure features Camfil Farr APC dust and fume collection systems to clean up industrial processes. The brochure provides a convenient two-page overview of the company s installed and portable dust collection equipment plus accessories and filters, industrial vacuums and other key products. Photos, features and benefits of each product are detailed. Camfil Farr APC, www.farrapc.com, filterman farrapc. com, (800) 479-6801 or (870) 933-8048. Circle 290... 

Bacterial adhesion and biofihns have been studied in situ by ATR [891, 902-904], For these measurements, special flow accessories are commercially available with a CIRCLE (Spectra-Tech, Stamford, CN) and trapezoidal (Spectra-Tech and Harrick Scientific) IRE. The latter is more suitable when the IR spectroscopic analysis is to be combined with another method, such as XPS or microscopic observation. An accessory with a trapezoidal IRE is described by Chittur et al. [841]. The use of a multichannel ATR/FTIR spectrometer specially designed for on-line examination of microbial biofilms [905] circumvents the problem of the reproducibility of the biofilm formation (see below). 

There are many types of ATR accessory. The old-style versions are the fully demountable type, with the ATR element (IRE) mounted vertically (traditional). The more modern variants include the horizontal ATR and the cylindrical ATR (such as the Circle and Tunnel cells). The traditional accessory is suitable for studying continuous surfaces, such as sheets or small blocks of compliant materials, and today it has relatively limited application. The horizontal accessories are ideal for liquids and pastes (trough versions) as well as soft powders and sheet films (flat plate versions). If a powder or film is to be analyzed with a horizontal ATR, pressure must be applied. The accessories are normally supplied with an optional pressure applicator for this purpose often equipped with a micrometer gauge for reproducible setting of the applied pressure. The cylindrical ATR accessories are normally limited to mobile liquids. 

Figure 11.25 Janecke prism (hexanary system Si3N4-Al203-Si02-AlN-YN-Y203) to visualize major crystalline phases (empty circles) and minor accessory phases (full circles). On the shaded plane Si2N20-Y40s-...

The Fendall 2000 Heated Accessory offers an innovative solution to the challenges presented by workplace environments that ate extremely cold or vary due to seasonal weather changes. Ideal for both indoor and outdoor applications, the portable station delivers unmatched versatility. Approved for use in temperatures as bw as -40 degrees Fahrenheit/Celsius, the accessory maintains eyewash solution at a tepid temperature (60-100 degrees Fahrenheit) to meet the ANSI Z358.1-2009 standard requiremenb. Sperian Eyewash, a Honeywell Company, www.honeywellsafety.com. Booth 2035. Circle 73... 

ATR accessories for the measurement of liquids are not restricted to IREs with a trapezoidal or parallelpiped geometry. Alternatively, liquids can be measured with cylindrical IREs. A cylindrical internal reflection element is a rod that has a cone at each end, as shown in Figure 15.10. The cone typically has a 45° half-angle at the apex. The IRE is sealed into a liquid cell that exposes most of the rod to the liquid, and only the ends of the cell extend beyond the cell. Two geometries for cylindrical IREs are shown in Figure 15.11. The first (Figme 15.11a) is the CIRCLE cell (Thermo Spectroscopy Division, Madison, Wisconsin), where CIRCLE is an... 

Both the CIRCLE and Tunnel cells can be filled and emptied remotely, and even be used for flow systems. Although these accessories are not sealed within the sample compartment, the sample compartment may be closed and only the flow lines need be accessible outside the spectrometer. The Tunnel cell also has the feature that the cell block can be temperature controlled with the use of either block electrical heaters or a coolant fluid. 

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