Atomic emission spectroscopy equipment

X-ray fluorescence, mass spectroscopy, emission spectrography, and ion-conductive plasma—atomic emission spectroscopy (icp—aes) are used in specialized laboratories equipped for handling radioisotopes with these instmments. 

The chemical composition of the catalysts was determined by inductively coupled plasma (ICP) atomic emission spectroscopy using a Thermo Jarrell Ash Iris Advantage equipment. 

The X-ray diffraction (XRD) patterns were obtained by Philips X pert Pro X-ray diffractometer equipped with a Cu-K source at 40 kV and 40 mA. The crystalline sizes of R particles were calculated from Scherrer s equation [15]. Transmission electron microscopy (TEM) images were obtained using the G2 FE-TEM Tecnai microscope at an accelerating voltage of 200 kV. The content of platinum and carbon in the sample was determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES, RF source Jobin Yvon 2301, 40.68 MHz). 

Once in solution, the preferred method for measurement of boron is inductively coupled plasma atomic emission spectroscopy (ICP-AES) or inductively coupled plasma mass spectrometry (ICP-MS). The most widely used nonspectrophotometric method for analysis of boron is probably ICP-MS because it uses a small volume of sample, is fast, and can detect boron concentrations down to 0.15 pgL . When expensive ICP equipment is not available, colorimetric or spectrophotometric methods can be used. However, these methods are often subject to interference (e.g., nitrate, chloride, fluoride), and thus must be used with caution. Azomethine-H has been used to determine boron in environmental samples (Lopez et al. 1993), especially water samples. Another simple, sensitive spectrophotometric method uses Alizarin Red S (Garcia-Campana et al. 1992). 

Of the different techniques for atomic emission spectroscopy (AES) only those which use a flame or an ICP are of any interest for analysis of biomedical specimens. Flame AES, also called flame photometry, has been an essential technique within clinical laboratories for measuring the major cations, sodium and potassium. This technique, usually with an air-propane flame, was also used to determine lithium in specimens from patients who were given this element to treat depression, and was employed by virtually all clinical laboratories throughout the world until the recent development of reliable, rapid-response ion selective electrodes. Biological fluids need only to be diluted with water and in modern equipment the diluter is an integral part of the instrument so that a specimen of plasma or urine can be introduced without any preliminary treatment. 

The atomic emission spectroscopy method was used in the study of inorganic admixture composition in PPA-1 and PPA-2, usually occurring from the equipment. The effect of metal increments on thermal stability was assessed by isothermal TGA, MFl and melt thermal stability data. 

The determination of sodium by atomic absorption spectroscopy has been applied successfully by several workers using a variety of equipment. The first element to be determined by Alkemade and Milatz (A2), in fact, was sodium. While sensitivity in emission is slightly higher for this metal than sensitivity in absorption, sodium still counts as one of the most sensitive elements in atomic absorption spectroscopy. The absence of any spectral interference (P3) and the relative freedom from other interferences appear to offer promising advantages of absorption over emission also for this element. 

In the past, the most common method of analysis of small anions has been ion-exchange chromatography. For cations, the preferred techniques have been atomic absorption spectroscopy and inductively coupled plasma emission spectroscopy. Recently, however, capillary electrophoretic methods have begun to compete with these traditional methods for small ion analysis. Several major reasons for adoption of electrophoretic methods have been recognized lower equipment costs, smaller sample size requirements, much greater speed, and better resolution. 

Most other metals present in pharmaceuticals are present in sufficient concentrations that high sensitivity is not imperative and they may therefore be determined by flame atomic absorption spectroscopy. These products are extremely variable in composition but nonetheless yield easily to this type of analysis, which is generally unaffected by compounding agents such as binders or expanders. Thus, the elements Na, K, Mg, Ca, Mn, Fe, Co, Cu, Zn, and Mo are among those determinable by flame (51-53) and, recently, furnace (54) atomic absorption in multivitamin-mineral tablets. Chemical interactions between some metals dictate the use of an internal standard when several elements are present simultaneously. It should be noted here that a spark emission or ICP spectrometer equipped with an appropriate polychromator would have the advantage of simultaneous and therefore more rapid analysis in these multielemental products. These techniques have probably not been fully utilized in this regard. 

GC can achieve the highest resolution of the essential oils, but there are some significant limitations with regards to preparative scale separations. Typically, as the sample capacity is increased, the resolution of the chromatographic separation is reduced. On a lab scale, equipment is available that permits 24-hour automated and unattended separations, however, the recovery yield and sample resolution are still problematic [57]. Capillary column GC has become so routine for essential oil analysis that one rarely finds a lab without that capability. A multitude of detectors exist for GC thermal conductivity (TCD), flame ionization (FID), flame photometric (FPD), thermionic specific (TSD), photoionization (PID), electron capture (ECD), atomic emission (AED), mass spectrometry (MS), and infrared spectroscopy (FTIR) [58,59]. The TCD is used primarily with preparative-GC (packed column) because it is... 

Even with the diflBculties cited above, the combination of flame emission and atomic absorption spectroscopy has become in a very short time one of our better methods for the analysis of waters for cations for the following reasons limited sample preparations necessary, high sensitivity, good analytical precision, low cost, and simphcity of equipment. 

Several different methods have been utilized for measuring iron in these biological samples. However, spectrophotometry is the most widely used because it does not require unusual equipment and is readily amenable to automation. Atomic absorption spectrometry is effectively used for tissue and urine analyses [33-35], but unreliable results are obtained with serum due to sensitivity limitations as well as matrix and hemoglobin interferences [35]. Other methods utilizing inductively coupled plasma emission spectroscopy [36], coulometry [37], proton induced X-ray emission [38], neutron activation analysis [39], radiative energy attenuation [40], and radiometry with Fe [41] have been described but, with the exception of coulometry, have not become standard procedures in the clinical chemistry laboratory, inasmuch as sophisticated and expensive instrumentation is required in some instances. However, some of them, e.g., neutron activation, may be the method of choice for definitive accurate analysis. 

Impurity inclusions and surface defects are a cause of many difficulties to the polymer producer and user. Equipment used for studying these phenomena discussed in Chapter 4 include electron microprobe x-ray emission/spectroscopy, NMR micro-imaging, various forms of surface infrared spectroscopy, e.g., diffusion reflection FTIR, ATR, also photoacoustic spectroscopy and x-ray diffraction - infrared microscopy of individual polymer fibres. Newer techniques such as scanning electron microscopy (SECM), transmission electron microscopy, time of flight secondary ion mass spectrometry (TOFSIMS), laser induced photoelectron ionisation with laser desorption, atomic force microscopy and microthermal analysis are discussed. 

This book is intended to fill the aforementioned gap and to present the basic principles and instrumentation involved in analytical atomic spectroscopy. To meet this objective, the book includes an elementary treatment of the origin of atomic spectra, the instrumentation and accessory equipment used in atomic spectroscopy, and the principles involved in arc-spark emission, flame emission, atomic absorption, and atomic fluorescence. 

The first volume contains the basic physical foundations of laser spectroscopy and the most important experimental equipment in a spectroscopic laboratory. It begins with a discussion of the fundamental definitions and concepts of classical spectroscopy, such as thermal radiation, induced and spontaneous emission, radiation power, intensity and polarization, transition probabilities, and the interaction of weak and strong electromagnetic (EM) fields with atoms. Since the coherence properties of lasers are important for several spectroscopic techniques, the basic definitions of coherent radiation fields are outlined and the description of coherently excited atomic levels is briefly discussed. 

X-ray spectroscopy, like optical spectroscopy, is based on measurement of emission, absorption, scattering, fluorescence, and diffraction of electromagnetic radiation. X-ray fluorescence and X-ray absorption methods are widely used for the qualitative and quantitative determination of all elements in,the periodic table having atomic numbers greater than that of sodium. With special equipment, elements with atomic numbers-in the range of 5 to 10 can also be determined. 

Since the introduction of the first commercially available atomic absorption spectrophotometer (AAS) in the early 1960s, there has been an increasing demand for better, faster, easier-to-use, and more flexible trace element instrumentation. A conservative estimate shows that today s market for atomic spectroscopy (AS)-based instruments, such as atomic absorption (AA), inductively coupled plasma optical emission (ICP-OES), and inductively coupled plasma mass spectrometry (ICP-MS), represents over 700 million in annual revenue. After market sales and service costs are added to this number, it is probably close to 1 billion. As a result of this growth, we have seen a rapid emergence of more sophisticated equipment and easier-to-use software. Moreover, with an increase in the number of manufacturers of both instrumentation and sampling accessories, the choice of which technique to use is often unclear. 

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