Journal articles: 'Atomic absorption spectroscopy – Instruments'

1

Appleton, John M. H., and Julian F. Tyson. "Flow injection atomic absorption spectrometry: the kinetics of instrument response." Journal of Analytical Atomic Spectrometry 1, no. 1 (1986): 63. http://dx.doi.org/10.1039/ja9860100063.

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Chen, Li Dan. "The Application of Atomic Absorption Spectroscopy on Detection of Engine Crankshaft Bearing Abnormal Sound." Advanced Materials Research 496 (March 2012): 427–30. http://dx.doi.org/10.4028/www.scientific.net/amr.496.427.

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By now, it is hard for an effective determination of the engine abnormal sound according to the existing auscultation method based on human experiences and diagnosis aided by instruments. For this reason, the author presented an innovative method that was by the using of atomic absorption spectroscopy technology for a rapid determination of the engine crankshaft bearing abnormal sounds. Major metals contents (Cu and Pb) in 20 batches of Audi A6 engine lubricating oil were detected by atomic absorption spectrometry. Samples were taken from the oil of mileages from 5000km to 69000km and 3000km intervals. Then the databases of main metal contents of different driving miles were built within the same vehicle type. This study showed that the main metal contents were fluctuating with the increasing of driving miles within certain range. For the practical application, we built a connection between engine abnormal sound faults and the major metal contents in the engine lubricating oil. By comparing the metal contents in problem engine with the established contents changing trends chart, we could get a rapid determination about the engine abnormal sound fault without disintegration of the car. To sum up, the achievements of this study helped to reduce vehicle maintenance costs and improved the fault diagnosis accuracy in abnormal sound of engine crankshaft bearing.

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Motooka, J. M. "An Exploration Geochemical Technique for the Determination of Preconcentrated Organometallic Halides by ICP-AES." Applied Spectroscopy 42, no. 7 (September 1988): 1293–96. http://dx.doi.org/10.1366/0003702884429913.

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An atomic absorption extraction technique which is widely used in geochemical exploration for the determination of Ag, As, Au, Bi, Cd, Cu, Mo, Pb, Sb, and Zn has been modified and adapted to a simultaneous inductively coupled plasma-atomic emission instrument. The experimental and operating parameters are described for the preconcentration of the metals into their organometallic halides and for the determination of these metals. Lower limits of determination are equal to or improved over those for flame atomic absorption (except Au), and ICP results are very similar to the accepted AA values, with precision for the ICP data in excess of that necessary for exploration purposes.

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Vecchiati, Giorgio, Francesco Fagioli, Giancarlo Torsi, Clinio Locatelli, Dionisio Mazzotta, and Antonella Pagnoni. "Standardless Analysis of Hg with the Cold Vapor Method: Evaluation of the Best Use of Modern Instrumentation." Applied Spectroscopy 56, no. 7 (July 2002): 859–62. http://dx.doi.org/10.1366/000370202760171527.

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The so-called cold vapor method is extensively used in atomic absorption spectroscopy for the quantitation of Hg and hydride forming elements. In the case of Hg it is possible to take advantage of the standardless method of analysis (which gives a quantitative result from a single measurement) if a stannous salt is used as a reducing agent. This type of analysis, which has the advantages of high sensitivity, low analysis time, and easy checking of the perfect working conditions of all the components of the apparatus, can be made with very slightly altered commercial instruments if flowmeters of good accuracy and precision are used. The mode of operation of modern commercial instruments can be either discontinuous, with a chromatographic-like injector, or continuous. A survey of the instruction manuals shows that virtually all manufacturers prefer the discontinuous mode. Our experimental results demonstrate that only with the continuous mode, if sufficient sample volume is available, is it possible to use the standardless method of analysis.

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Ahmadi, R., Madaah Hosseini, and A. Masoudi. "Avrami behavior of magnetite nanoparticles formation in co-precipitation process." Journal of Mining and Metallurgy, Section B: Metallurgy 47, no. 2 (2011): 211–18. http://dx.doi.org/10.2298/jmmb110330010a.

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In this work, magnetite nanoparticles (mean particle size about 20 nm) were synthesized via coprecipitation method. In order to investigate the kinetics of nanoparticle formation, variation in the amount of reactants within the process was measured using pH-meter and atomic absorption spectroscopy (AAS) instruments. Results show that nanoparticle formation behavior can be described by Avrami equations. Transmission electron microscopy (TEM) and X-ray diffraction (XRD) were performed to study the chemical and morphological characterization of nanoparticles. Some simplifying assumptions were employed for estimating the nucleation and growth rate of magnetite nanoparticles.

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Maria, Guţu Claudia, Bălălău D, Ilie Mihaela, Purdel Carmen Nicoleta, and Gubandru Miriana. "Quantitative Determination of Arsenic in Bottled Drinking Water Using Atomic Absorption Spectroscopy." Acta Medica Marisiensis 59, no. 5 (October 1, 2013): 246–49. http://dx.doi.org/10.2478/amma-2013-0056.

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Abstract Background: Many studies have been performed in the past few years, to determine arsenic speciation in drinking water, food chain and environment, arsenic being a well-recognized carcinogenic and toxic agent mainly in its inorganic species. The instrumental techniques used for arsenic determination, such as hydride generation atomic absorption spectrometry (HGAAS), graphite furnace atomic absorption spectrometry (GFAAS) and inductively coupled plasma mass spectrometry (ICP-MS), can provide a great sensitivity only on the total amount. Objective: The aim of this study was to develop a simple and rapid method and to analyze the concentration of total inorganic arsenic in bottled drinking water. Methods: Total arsenic was determined in samples from six different types of commercially available bottled drinking water using atomic absorption spectrometry with electrothermal or hydride generation vaporisation. All drinking water samples were acidified with 0.1M nitric acid to match the acidity of the standards. Results: The method was linear within the studied range (1-5 μg/L, R = 0.9943). The quantification limits for arsenic determination were 0.48 μg/L (HGAAS) and 0.03 μg/L (GFAAS). The evaluated arsenic content in drinking water was within the accepted limits provided by law. Conclusions: A simple and sensitive method for the quantification of arsenic in drinking water using atomic absorbtion spectroscopy was described, which can be further used in toxicological studies. As an additional advantage, the system is very fast, efficient and environmental friendly

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Huotari, Simo. "X-ray Raman scattering spectroscopy." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C219. http://dx.doi.org/10.1107/s2053273314097800.

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For elements with low atomic number, or shallow absorption edges falling in the energy range below ~1 keV, x-ray absorption studies are often limited by surface sensitivity and the necessity of a vacuum environment, making bulk-sensitive measurements and for example studies of liquids difficult. An exciting alternative is provided by X-ray Raman scattering (XRS) spectroscopy. It is used to measure a photon-in-photon-out process, where a hard x-ray photon loses only part of its energy creating an excitation of an inner core electron. As such, it is the x-ray analogue of electron energy loss spectroscopy. The advantage of XRS is that the incident photon energy can be chosen freely and thus low-energy absorption edges can be studied with high-energy X-rays. Thus XRS is becoming increasingly popular since it allows for bulk-sensitive measurements of inner core spectra where the corresponding x-ray absorption threshold falls into the soft x-ray regime. This lifts all constraints on the sample environment inherent to soft x-ray studies, and offers access to bulk-sensitive information on solids, liquids and gases as well as systems in enclosed sample environments such as high-pressure cells. For example the microscopic structure of water within the supercritical regime has been recently studied using the oxygen K-edge excitation spectra measured by XRS, yielding new information on the hydrogen-bond network of water in extreme conditions [1]. Another important feature of XRS is that it allows for other than dipole transitions to be studied, thanks to an practically unlimited range of momentum transfer offered by hard x-rays. These higher order multipole excitations can yield novel information on the electronic structure, not accessible by many other spectroscopies [2]. The availability of XRS instruments at third-generation synchrotron radiation sources has made highly accurate XRS measurements possible. XRS can be even used as a contrast mechanism in three-dimensional X-ray imaging [3]. In this contribution, the capabilities of XRS and recent examples of novel studies allowed by it will be reviewed.

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Sakurai, Kenji, and Xiaomei Guo. "Recent performance of laboratory-scale X-ray absorption fine structure instruments." Spectrochimica Acta Part B: Atomic Spectroscopy 54, no. 1 (January 1999): 99–107. http://dx.doi.org/10.1016/s0584-8547(98)00181-5.

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Horoyski, P. J., and M. L. W. Thewalt. "Fourier Transform Raman and Brillouin Spectroscopy Using Atomic Vapor Filters." Applied Spectroscopy 48, no. 7 (July 1994): 843–47. http://dx.doi.org/10.1366/0003702944029866.

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This paper presents Raman and Brillouin scattering measurements obtained with a Fourier transform interferometer, in which the laser light rejection was provided by an alkali-metal vapor cell. The narrow absorption band of the vapor cell allowed for the detection of energy shifts as low as 0.85 cm−1(∼26 GHz) while completely blocking scattered light at the laser frequency. Since, unlike a Fabry-Perot interferometer, a Fourier transform interferometer does not have a free spectral range placing an upper bound on the energy shifts which it can detect without ambiguity, the energy regimes of both Brillouin and Raman scattering are for the first time accessible with a single instrument.

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Sanford, Caryn L., Susan E. Thomas, and Bradley T. Jones. "Portable, Battery-Powered, Tungsten Coil Atomic Absorption Spectrometer for Lead Determinations." Applied Spectroscopy 50, no. 2 (February 1996): 174–81. http://dx.doi.org/10.1366/0003702963906591.

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A compact, inexpensive atomic absorption spectrometer has been designed, constructed, and evaluated for the determination of lead at the μg/L level. The new device is made feasible by the combination of a reliable tungsten coil atomizer, a miniature spectrometer/charge-coupled device combination mounted on a PC card, and a near-line background-correction method. The finished spectrometer can be powered by a normal 12-V car battery, controlled with a laptop computer, and transported in any automobile. The overall dimensions of the original prototype system are 19 in. × 8 in. × 3 in. (excluding the computer), and it has no moving parts. The total estimated cost of the system including the computer is less than $6000. The limit of detection for Pb is 20 pg (20-μL sample volume), the linear dynamic range is two orders of magnitude, and the precision for the technique is 5% RSD at concentrations ten times greater than the detection limit. The accuracy of the technique was determined with the use of NIST SRM #1579a “Powdered Lead-Based Paint” containing 11.995 wt % Pb and NIST SRM 955a “Lead in Blood” containing 54.43 μg/dL Pb. The accuracy for the paint sample was 95.1% (11.41 wt % found) with the use of the calibration curve method (aqueous standards) and 97.2% (11.66 wt % found) with the method of standard additions. The accuracy for the blood sample was 93.5% (50.9 μg/dL found) with the calibration curve method and 96.6% (56.3 μg/dL found) with the method of standard additions. The limiting source of noise for the instrument is detector noise, so that the performance of the device can be improved by increasing the optical throughput of the system.

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Ferlemann, Frieder, Nadine Bauer, Richard Fitzenberger, Hartwig Harder, Hartmut Osterkamp, Dieter Perner, Ulrich Platt, Matthias Schneider, Paul Vradelis, and Klaus Pfeilsticker. "Differential optical absorption spectroscopy instrument for stratospheric balloonborne trace-gas studies." Applied Optics 39, no. 15 (May 20, 2000): 2377. http://dx.doi.org/10.1364/ao.39.002377.

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Lucic, M., and V. Krivan. "Slurry Sampling Electrothermal Atomic Absorption Spectrometry for the Analysis of Aluminum-Based Ceramic Powders." Applied Spectroscopy 52, no. 5 (May 1998): 663–72. http://dx.doi.org/10.1366/0003702981944328.

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A slurry sampling electrothermal atomic absorption spectrometry method for the determination of Ca, Cr, Cu, K, Fe, Mg, Mn, Na, Ni, and Zn in aluminum oxide and aluminum nitride powders is described. For each analyte, the experimental conditions including atomization temperature, internal gas flow during atomization, and pyrolytic re-coating of the graphite tube were optimized with respect to the sensitivity and background absorption. Quantification was performed by means of calibration curves recorded with the use of aqueous standards. The achievable limits of detection are between 5 ng/g (K) and 130 ng/g (Fe). The accuracy was checked by comparison of the results with those obtained by instrumental and radiochemical neutron activation analysis and other methods.

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Nixon, D. E., T. P. Moyer, P. Johnson, J. T. McCall, A. B. Ness, W. H. Fjerstad, and M. B. Wehde. "Routine measurement of calcium, magnesium, copper, zinc, and iron in urine and serum by inductively coupled plasma emission spectroscopy." Clinical Chemistry 32, no. 9 (September 1, 1986): 1660–65. http://dx.doi.org/10.1093/clinchem/32.9.1660.

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Abstract We describe an inductively coupled plasma atomic emission spectrometer that has been adapted to perform routine, simultaneous, direct analyses of calcium, magnesium, copper, zinc, and iron in serum or urine without sample digestion or pretreatment. The system, constructed with inexpensive, readily available components, can analyze 1-mL or smaller samples. Results correlate nearly perfectly with those derived by standard atomic absorption techniques (r = 0.98 to 0.997). Using certified serum and urine samples from various sources, we demonstrate that the instrument yields accurate results with a precision better than certified values. The instrument is sensitive to one order of magnitude less than the lower limit of the normal range in serum or urine for all elements tested, and responds linearly to concentrations two orders of magnitude higher than the upper limit of the normal range. With the system described here, these five elements can be assayed with the same or less technical effort than needed for a single element by atomic absorption.

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Oikari, Risto, Ville Häyrinen, Tomi Parviainen, and Rolf Hernberg. "Continuous Monitoring of Toxic Metals in Gas Flows Using Direct-Current Plasma Excited Atomic Absorption Spectroscopy." Applied Spectroscopy 55, no. 11 (November 2001): 1469–77. http://dx.doi.org/10.1366/0003702011953883.

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A measurement apparatus employing direct current (dc) plasma excited atomic absorption spectroscopy was developed and demonstrated for continuous measurement of toxic metals in process gases. Process gas is continuously sampled along a heated sample line. Metal compounds contained in the gas are thermally decomposed by mixing the gas with a plasma jet produced with a dc nitrogen plasma torch. Transmission of monochromatic light is measured through the gas jet, and absorbance caused by metal atoms is distinguished from the background by means of the Zeeman effect. The metal concentration in the sample gas is calculated from the measured absorbance with the known dilution and decomposition factors taken into account. The detection limits of the current prototype are 0.04 mg/m3 for cadmium and 0.4 mg/m3 for lead. The measurement accuracy is better than 20%, and the maximum measurement rate is about 100 values per minute. The instrument was designed to withstand wet, corrosive, and particulate-laden flue gases at temperatures up to 1100 °C. The instrument can also be used, after minor modification, for measurements at pressurized conditions. The performance of the instrument was demonstrated in connection with a real fluidized bed combustor.

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Christensen, Warren, James K. Johnson, Grace R. Van Ness, Elliot Mylott, Justin C. Dunlap, Elizabeth A. Anderson, and Ralf Widenhorn. "Developing and Assessing Curriculum on the Physics of Medical Instruments." CBE—Life Sciences Education 12, no. 2 (June 2013): 250–61. http://dx.doi.org/10.1187/cbe.12-09-0142.

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Undergraduate educational settings often struggle to provide students with authentic biologically or medically relevant situations and problems that simultaneously improve their understanding of physics. Through exercises and laboratory activities developed in an elective Physics in Biomedicine course for upper-level biology or pre–health majors at Portland State University, we aim to teach fundamental physical concepts, such as light absorption and emission and atomic energy levels, through analysis of biological systems and medical devices. The activities address the properties of electromagnetic waves as they relate to the interaction with biological tissue and make links between physics and biomedical applications such as microscopy or laser eye surgery. We report on the effect that engaging students in tasks with actual medical equipment has had on their conceptual understanding of light and spectroscopy. These initial assessments indicate that students’ understanding improves in some areas as a result of taking the course, but gains are not uniform and are relatively low for other topics. We also find a promising “nonshift” in student attitudes toward learning science as a result of taking the course. A long-term goal of this work is to develop these materials to the extent that they can eventually be imported into an introductory curriculum for life sciences majors.

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Hoeijmakers, H. Jens, Samuel H. C. Cabot, Lily Zhao, Lars A. Buchhave, René Tronsgaard, Allen B. Davis, Daniel Kitzmann, et al. "High-resolution transmission spectroscopy of MASCARA-2 b with EXPRES." Astronomy & Astrophysics 641 (September 2020): A120. http://dx.doi.org/10.1051/0004-6361/202037437.

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We report detections of atomic species in the atmosphere of MASCARA-2 b, using the first transit observations obtained with the newly commissioned EXPRES spectrograph. EXPRES is a highly stabilized optical echelle spectrograph, designed to detect stellar reflex motions with amplitudes down to 30 cm s−1, and has recently been deployed at the Lowell Discovery Telescope. By analyzing the transmission spectrum of the ultra-hot Jupiter MASCARA-2 b using the cross-correlation method, we confirm previous detections of Fe I, Fe II, and Na I, which likely originate in the upper regions of the inflated atmosphere. In addition, we report significant detections of Mg I and Cr II. The absorption strengths change slightly with time, possibly indicating different temperatures and chemistry in the day- and nightside terminators. Using the effective stellar line-shape variation induced by the transiting planet, we constrain the projected spin-orbit misalignment of the system to 1.6 ± 3.1 degrees, consistent with an aligned orbit. We demonstrate that EXPRES joins a suite of instruments capable of phase-resolved spectroscopy of exoplanet atmospheres.

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Somov, A. R., A. Kh Gil’mutdinov, and L. A. Grishin. "Taking into account physical and instrumental parameters in atomic absorption spectroscopy with a continuous radiation source." Journal of Applied Spectroscopy 73, no. 3 (May 2006): 317–22. http://dx.doi.org/10.1007/s10812-006-0077-1.

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Sheth, Alpa C., and Paresh U. Patel. "Review of Elemental Impurities in Pharmaceuticals Arena." INTERNATIONAL JOURNAL OF PHARMACEUTICAL QUALITY ASSURANCE 11, no. 02 (June 25, 2020): 214–18. http://dx.doi.org/10.25258/ijpqa.11.2.3.

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Elemental impurities in drug products may arise from several sources; they may be residual catalysts that were added intentionally in the synthesis or may be present as impurities (e.g., through interactions with processing equipment or container/closure systems or by being present in components of the drug product). Because elemental impurities do not provide any therapeutic benefit to the patient, their levels in the drug product should be controlled within acceptable limits. The main objective of the International Conference on Harmonization (ICH) (Q3D) guideline applies to new finished drug products and new drug products containing existing drug substances. The drug products containing purified proteins and polypeptides. This guideline does not apply to herbal products, radiopharmaceuticals, vaccines, cell metabolites, DNA products, allergenic extracts, cells, whole blood, cellular blood components, or blood derivatives, including plasma and plasma derivatives. The evaluation of the toxicity data for potential elemental impurities; the establishment of a permitted daily exposure (PDE) for each element of toxicological concern; application of a risk-based approach to control elemental impurities in drug products. Different analytical techniques for elemental impurities detection: flame atomic absorption spectrometry (FAAS), graphite furnace atomic absorption spectrometry (GFAAS), atomic fluorescence spectrometry, X-ray fluorescence spectrometry (XRF), instrumental neutron activation analysis (INAA), inductively coupled plasma-atomic emission spectroscopy (optical emission spectroscopy, ICP-OES), inductively coupled plasma mass spectrometry (ICP-MS), and microwave plasma atomic emission spectrometry (MP-AES).

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Mohammed, Elisabeth, Terry Mohammed, and Azad Mohammed. "Optimization of instrument conditions for the analysis for mercury, arsenic, antimony and selenium by atomic absorption spectroscopy." MethodsX 5 (2018): 824–33. http://dx.doi.org/10.1016/j.mex.2018.07.016.

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Stender, Anthony S., Lindsay A. Giem, Matt C. Bunte, Carrie L. Burns, Lindsay D. Odom, Diane S. Fitzpatrick, Christopher J. Biorn, and Eugene T. Smith. "Determination of Arsenic in Drinking Water by Graphite Furnace Atomic Absorption Spectroscopy. An Undergraduate Instrumental Analysis Laboratory." Chemical Educator 5, no. 6 (December 2000): 321–23. http://dx.doi.org/10.1007/s00897000428a.

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Motkosky, Norine, Angelo Ransirimal Fernando, and Byron Kratochvil. "Elemental analysis of the marine biological reference material LUTS-1 by instrumental neutron activation, graphite furnace atomic absorption spectroscopy, and anodic stripping voltammetry." Canadian Journal of Chemistry 68, no. 5 (May 1, 1990): 735–40. http://dx.doi.org/10.1139/v90-116.

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Marine biological reference material LUTS-1, lobster heptopancreas, was analyzed for elemental homogeneity using graphite furnace atomic absorption, anodic stripping voltammetry, and neutron activation analysis. Analysis of samples taken from 12 bottles of LUTS-1 bottled on two different days showed no statistical differences at the 95% confidence level for within-bottle variance for a large number of elements. Differences were observed for between-day variances for aluminum, iron, cobalt, sodium, chlorine, bromine, and iodine, but not at a level sufficient to affect utility as a reference material. Keywords: neutron activation analysis, graphite furnace atomic absorportion spectroscopy, anodic stripping voltammetry, elemental analysis, marine biological reference material.

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Li, Bin, Liang Xue, Nan Ji, and Da Hui Wei. "Research on Spectroscopy Modulation of a Distributed Feedback Laser Diode Based on the TDLAS Technique." International Journal of Optics 2021 (July 24, 2021): 1–9. http://dx.doi.org/10.1155/2021/8829790.

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Laser current and temperature control circuits have been developed for a distributed feedback laser diode, which is applied as the light source of a tuneable diode laser absorption spectroscopy system. The laser’s temperature fluctuation can be limited within the range of −0.02 to 0.02°C, and good operation stability was observed through 15 hours of monitoring on the emitting wavelength of the laser. Response time of temperature modulation was tested which is suitable for the tuning requirements of gas detection systems. Laser current can be injected within the range from 40 to 80 mA. In addition, a linear power supply circuit has been developed to provide stable and low-noise power supply for the system. The physical principles of laser modulation theory are discussed before experiments. Experiments show that the output wavelength of the laser can be tuned accurately through changing the working current and temperature. The wavelength can be linearly controlled by temperature at 0.115 nm/°C (I = 70 mA) and be controlled by current at 0.0140 nm/mA (T = 25°C). This is essential for the tuneable diode laser absorption spectroscopy systems. The proposed cost-effective circuits can replace commercial instruments to drive the laser to meet the requirements of methane detection experiments. It can also be applied to detect other gases by changing the light source lasers and parameters of the circuits.

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Khalafinejad, Sara, Michael Salz, Patricio E. Cubillos, George Zhou, Carolina von Essen, Tim-Oliver Husser, Daniel D. R. Bayliss, et al. "The atmosphere of WASP-17b: Optical high-resolution transmission spectroscopy." Astronomy & Astrophysics 618 (October 2018): A98. http://dx.doi.org/10.1051/0004-6361/201732029.

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High-resolution transmission spectroscopy is a method for understanding the chemical and physical properties of upper exoplanetary atmospheres. Due to large absorption cross-sections, resonance lines of atomic sodium D-lines (at 5889.95 and 5895.92 Å) produce large transmission signals. Our aim is to unveil the physical properties of WASP-17b through an accurate measurement of the sodium absorption in the transmission spectrum. We analyze 37 high-resolution spectra observed during a single transit of WASP-17b with the MIKE instrument on the 6.5 m Magellan Telescopes. We exclude stellar flaring activity during the observations by analyzing the temporal variations of Hα and Ca II infrared triplet (IRT) lines. We then obtain the excess absorption light curves in wavelength bands of 0.75, 1, 1.5, and 3 Å around the center of each sodium line (i.e., the light curve approach). We model the effects of differential limb-darkening, and the changing planetary radial velocity on the light curves. We also analyze the sodium absorption directly in the transmission spectrum, which is obtained by dividing in-transit by out-of-transit spectra (i.e., the division approach). We then compare our measurements with a radiative transfer atmospheric model. Our analysis results in a tentative detection of exoplanetary sodium: we measure the width and amplitude of the exoplanetary sodium feature to be σNa = (0.128 ± 0.078) Å and ANa = (1.7 ± 0.9)% in the excess light curve approach and σNa = (0.850 ± 0.034) Å and ANa = (1.3 ± 0.6)% in the division approach. By comparing our measurements with a simple atmospheric model, we retrieve an atmospheric temperature of 15501550 −200+700 K and radius (at 0.1 bar) of 1.81 ± 0.02 RJup for WASP-17b.

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Nurfazliana, Mohd Fauzee, Sharul Ashikin Kamaruddin, Nayan Nafarizal, Hashim Saim, and Mohd Zainizan Sahdan. "Effects of Annealing Process on the Structural, Optical and Electrical Properties of Copper Oxide Thin Films Grown by Immersion Technique." Advanced Materials Research 1133 (January 2016): 439–43. http://dx.doi.org/10.4028/www.scientific.net/amr.1133.439.

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The synthesized and characterization on the growth of copper oxide thin films on fluorine-doped tin oxide (FTO) coated glass with annealing and without annealing process has been studied by immersion techniques. Furthermore, ZnO layer has been used in order to improved the absorption spectrum of CuO films. The copper oxide films were analyzed on the morphological, structural, optical and electrical by field emission scanning electron microscopy (FESEM), X-ray diffractometer (XRD), UV-Vis spectroscopy (absorbance) and I-V characteristics instruments. The atomic force microscope (AFM) was used in order to characterize the surface imaging of copper oxide films and the thicknesses were measured using a surface profiler. The AFM studies revealed that the roughness of the CuO films increased after annealing was applied this is due to the formation of large clusters of grains from the merging of small clusters grains. The CuO films thicknesses also becomes two times higher than the CuO films without annealing process.

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Lisichkov, Kiril, Katerina Atkovska, Neven Trajchevski, Orce Popovski, and Nadica Todorovska. "DETERMINATION OF ARSENIC, CADMIUM, LEAD, COOPER AND ZINC IN DRINKING WATER FROM R. MACEDONIA." Knowledge International Journal 28, no. 4 (December 10, 2018): 1259–64. http://dx.doi.org/10.35120/kij28041259k.

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The presence of some chemical compounds at higher levels than maximum permissible concentrations (MPC) in the drinking water, suggests of water resources pollution. In this paper the following elements were analyzed: total arsenic, cadmium, lead, cooper and zinc. Twelve samples of water from the water supply system from the city of Skopje were examined during one year from three different springs. Also, ten samples of bottled water from three producers from the Macedonian market were tested.The determined average mass concentrations of total As, Cd(II), Pb(II), Cu(II) and Zn(II) in the analyzed water samples from the water supply system are 1.35 μg/l, 0.06 μg/l, 0.6 μg/l, 0.9 μg/l and 1,12 μg/l, respectively, and for the tested bottled water, the mean values ranges from 0.56 - 0.83 μg total As / l, 0.053 - 0.056 μg Cd(II)/l, 0.51 - 0.54 μg Pb(II)/l , 0.6 - 0.87 μg Cu(II)/l and 0.68 - 0.8 μg Zn(II)/l water.The following instrumental analytical methods and techniques were used for the analysis of the tested samples of drinking water: flame atomic absorption spectroscopy (AAS), atomic absorption spectroscopy with hydride cеll, electrothermal atomic absorption spectroscopy.The obtained results are shown in tables and graphic form. According to the obtained results a comparative analysis was carried out indicate that it is a water of good quality that can be used in different branches of the process industry.The obtained results in this paper do not exceed the values of the MPC of the Republic of Macedonia prescribed by the legal regulations for the drinking water, which confirm the health safety of the drinking water from the water supply system in the city of Skopje and the packed waters from the Macedonian market in relation to the tested elements.

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Singare, Pravin, Ram Lokhande, Mahadeo Andhale, and Raghunath Acharya. "Availability of essential trace elements in ayurvedic Indian medicinal herbs using instrumental neutron activation analysis and atomic absorption spectroscopy." World Journal of Science, Technology and Sustainable Development 7, no. 2 (May 2010): 175–90. http://dx.doi.org/10.1108/20425945201000012.

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Gómez Martín, J. C., J. Blahins, U. Gross, T. Ingham, A. Goddard, A. S. Mahajan, A. Ubelis, and A. Saiz-Lopez. "In situ detection of atomic and molecular iodine using Resonance and Off-Resonance Fluorescence by Lamp Excitation: ROFLEX." Atmospheric Measurement Techniques 4, no. 1 (January 19, 2011): 29–45. http://dx.doi.org/10.5194/amt-4-29-2011.

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Abstract. We demonstrate a new instrument for in situ detection of atmospheric iodine atoms and molecules based on atomic and molecular resonance and off-resonance ultraviolet fluorescence excited by lamp emission. The instrument combines the robustness, light weight, low power consumption and efficient excitation of radio-frequency discharge light sources with the high sensitivity of the photon counting technique. Calibration of I2 fluorescence is achieved via quantitative detection of the molecule by Incoherent Broad Band Cavity-enhanced Absorption Spectroscopy. Atomic iodine fluorescence signal is calibrated by controlled broad band photolysis of known I2 concentrations in the visible spectral range at atmospheric pressure. The instrument has been optimised in laboratory experiments to reach detection limits of 1.2 pptv for I atoms and 13 pptv for I2, for S/N = 1 and 10 min of integration time. The ROFLEX system has been deployed in a field campaign in northern Spain, representing the first concurrent observation of ambient mixing ratios of iodine atoms and molecules in the 1–350 pptv range.

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Gómez Martín, J. C., J. Blahins, U. Gross, T. Ingham, A. Goddard, A. S. Mahajan, A. Ubelis, and A. Saiz-Lopez. "In situ detection of atomic and molecular iodine using resonance and off-resonance fluorescence by lamp excitation: ROFLEX." Atmospheric Measurement Techniques Discussions 3, no. 4 (August 25, 2010): 3803–49. http://dx.doi.org/10.5194/amtd-3-3803-2010.

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Abstract. We demonstrate a new instrument for in situ detection of atmospheric iodine atoms and molecules based on atomic and molecular resonance and off-resonance ultraviolet fluorescence excited by lamp emission. The instrument combines the robustness, light weight, low power consumption and efficient excitation of radio-frequency discharge light sources with the high sensitivity of the photon counting technique. Calibration of I2 fluorescence is achieved via quantitative detection of the molecule by incoherent broad band cavity-enhanced absorption spectroscopy. Atomic iodine fluorescence signal is calibrated by controlled broad band photolysis of known I2 concentrations in the visible spectral range at atmospheric pressure. The instrument has been optimised in laboratory experiments to reach detection limits of 1.2 pptv for I atoms and 20 pptv for I2, for S/N=1 and 10 min of integration time. The ROFLEX system has been deployed in a field campaign in Northern Spain, representing the first concurrent observation of ambient mixing ratios of iodine atoms and molecules in the 1–350 pptv range.

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Pundt, Irene, and Kai Uwe Mettendorf. "Multibeam long-path differential optical absorption spectroscopy instrument: a device for simultaneous measurements along multiple light paths." Applied Optics 44, no. 23 (August 10, 2005): 4985. http://dx.doi.org/10.1364/ao.44.004985.

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Zorina, Natalja, Atis Skudra, Gita Revalde, and Zanda Gavare. "COMPARISON OF AS, HG AND TL HIGH-FREQUENCY ELECTRODELESS LAMPS FOR DETECTION OF ENVIRONMENTAL POLLUTION." ENVIRONMENT. TECHNOLOGIES. RESOURCES. Proceedings of the International Scientific and Practical Conference 1 (June 16, 2021): 275–80. http://dx.doi.org/10.17770/etr2021vol1.6529.

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Nowadays, there is an increasing necessity to determine the concentration of different substances in the environment in low concentrations, as more and more attention is paid to environmental pollution. This work is devoted to the comparison of main characteristics of high-frequency electrodeless light sources with different fillings for their use in high precision atomic absorption analysers.The spectral line intensities and profiles were studied in special design light sources, manufactured at Institute of Atomic Physics and Spectroscopy, with arsenic, mercury and thallium filling. Special attention is devoted to the UV lines of 193.7 nm and 197.2 nm of As, 276.8 nm, 377.6 nm of Tl and 253.7 nm of Hg spectral lines. The intensities and profiles were measured by means of a Fourier transform spectrometer.The deconvolution procedure was implemented to obtain the real form of emitted profiles for further analysis, since in the case of low –pressure or cold plasma, the instrumental function is on the same order that experimental profile and it has to be taken into account. The instrumental function can distort the real spectral line shape significantly, for example, it changes the width of the spectral line that leads to the uncertainties in the determination of such important plasma parameters like temperature. The instrumental function can conceal a detailed structure of the spectral line, like the dip in the line center caused by the self-absorption (self-reversal) and characterizing the radiation trapping.The integrated areas, values of self-absorption, and other parameters were obtained and compared for all fillings as a function of working regimes.

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Nuguyeva, Sh, and E. Mammadov. "Research of the Content of Heavy Metals in the Atmospheric Precipitation of the Geygel, Dashkesan and Gedabek Districts of Azerbaijan." Bulletin of Science and Practice 7, no. 6 (June 15, 2021): 60–66. http://dx.doi.org/10.33619/2414-2948/67/08.

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The increasing content of heavy metals in soil and atmospheric air can lead to serious consequences in the final link of which a person is. To determine heavy metals in atmospheric deposition, the method of biomonitoring of mosses was used. Joint Institute for Nuclear Research scientists started the implementation of the mosses biomonitoring methodology in Azerbaijan 2015. In total, the concentration was determined for 44 elements. Determinations were performed using instrumental analysis of Epithermal Neutron Activation and Atomic Absorption Spectroscopy in 85 moss samples. The species of moss used in the work was Pleurosium schreberi. Based on the analysis results, the most contaminated areas are identified.

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Khan, M. Z. H., M. R. Hasan, M. Khan, S. Aktar, and K. Fatema. "Distribution of Heavy Metals in Surface Sediments of the Bay of Bengal Coast." Journal of Toxicology 2017 (2017): 1–7. http://dx.doi.org/10.1155/2017/9235764.

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The concentrations of major (Si, Al, Ca, Fe, and K) and minor (Cd, Mn, Ni, Pb, U, Zn, Co, Cr, As, Cu, Rb, Sr, and Zr,) elements in the surficial sediments were studied in an attempt to establish their concentration in the Bengal coast. It was revealed that the majority of the trace elements have been introduced into the Bengal marine from the riverine inflows that are also affected by the impact of industrial, ship breaking yard, gas production plant, and urban wastes. The concentration of heavy metals was measured using Atomic Absorption Spectroscopy and Energy Dispersive X-ray fluorescence instruments. The highest concentrations for several trace elements were thus recorded which generally decrease with distance from the coast. It was observed that the heavy metal concentrations in the sediments generally met the criteria of international marine sediment quality. However, both the contamination factor and pollution load index values suggested the elevation of some metals’ concentrations in the region. Constant monitoring of the Bengal coast water quality needs to be recorded with a view to minimizing the risk of health of the population and the detrimental impacts on the aquatic ecosystem.

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Lokhande, Ram S., Mahadeo L. Andhale, and Pravin U. Singare. "Analysis of essential trace elements in some traditional Indian medicinal plants using instrumental neutron activation analysis and atomic absorption spectroscopy techniques." International Journal of Immunological Studies 1, no. 3 (2011): 285. http://dx.doi.org/10.1504/ijis.2011.041726.

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Woźniak, Magdalena, and Izabela Ratajczak. "A reaction of [3-(2-aminoethylamino)propyl]trimethoxysilane with wood and cellulose – chemical analyses." Annals of WULS, Forestry and Wood Technology 109 (March 31, 2020): 43–47. http://dx.doi.org/10.5604/01.3001.0014.3155.

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A reaction of [3-(2-aminoethylamino)propyl]trimethoxysilane with wood and cellulose – chemical analyses. The paper presents tests results for [3-(2-aminoethylamino)propyl]trimethoxysilane (AATMOS) reactivity with cellulose and Scots pine wood. The tested material was treated with ethanolic solution of aminosilane and analyzed using instrumental methods, including elemental analysis, atomic absorption spectrometry and infrared spectroscopy. The results of the chemical analysis indicated that [3-(2-aminoethylamino)propyl]trimethoxysilane exhibited reactivity with both cellulose and pine wood. In addition, AATMOS-treated cellulose showed a higher content of silicon and nitrogen and more significant changes in FTIR spectra than the treated wood, suggesting that AATMOS showed a higher reactivity to cellulose than to wood.

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Woźniak, Magdalena, and Izabela Ratajczak. "Reactivity of (3-aminopropyl)trimethoxysilane with cellulose." Annals of WULS, Forestry and Wood Technology 109 (March 31, 2020): 53–57. http://dx.doi.org/10.5604/01.3001.0014.3161.

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Reactivity of (3-aminopropyl)trimethoxysilane with cellulose. The paper presents the results of tests for the reactivity of (3-aminopropyl)trimethoxysilane (APTMOS) with cellulose. The cellulose was treated with aqueous ethanolic solution of silane in two concentration: 5% and 20%. The reactivity of APTMOS with cellulose was analysed using instrumental methods: attenuated total reflectance Fourier transform infrared spectroscopy, atomic absorption spectrometry and elemental analysis. In the FTIR spectra of silane-treated cellulose, the bands of Si-O, Si-C and N-H bonds were detected. The analysis of silicon and nitrogen concentration in treated cellulose confirmed the presence of silane in cellulose structure. The presented results indicate that APTMOS forms chemical bonds with cellulose.

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Nurmin, Nurmin, Sri Mulyani Sabang, and Irwan Said. "Penentuan Kadar Natrium (Na) dan Kalium (K) dalam Buah Pisang Kepok (Musa paradisiaca L.) Berdasarkan Tingkat Kematangannya." Jurnal Akademika Kimia 7, no. 3 (August 30, 2018): 115. http://dx.doi.org/10.22487/j24775185.2018.v7.i3.11906.

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This study aimed to determine sodium (Na) and potassium (K) levels in the fruit of banana kepok (Musa paradisiaca L.). The method used in this study was a laboratory experiment using atomic absorption spectroscopy (AAS) instrument. The result showed that the sodium (Na) levels in unripe, ripe, and overripe bananas were 129.83 mg/kg, 125.15 mg/kg, and 122.65 mg/kg, respectively. While the potassium (K) level obtained from unripe, ripe, and overripe bananas was 266.76 mg/kg, 258.61 mg/kg, and 255.22 mg/kg, respectively. Based on these results, it can be concluded that sodium and potassium levels in unripe bananas kepok fruit were higher than in ripe and overripe bananas, moreover, the potassium levels were higher than the sodium levels.

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Wilson, Jamie, Neale P. Gibson, Joshua D. Lothringer, David K. Sing, Thomas Mikal-Evans, Ernst J. W. de Mooij, Nikolay Nikolov, and Chris A. Watson. "Gemini/GMOS optical transmission spectroscopy of WASP-121b: signs of variability in an ultra-hot Jupiter?" Monthly Notices of the Royal Astronomical Society 503, no. 4 (March 22, 2021): 4787–801. http://dx.doi.org/10.1093/mnras/stab797.

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ABSTRACT We present ground-based, spectroscopic observations of two transits of the ultra-hot Jupiter WASP-121b covering the wavelength range ≈500–950 nm using Gemini/GMOS. We use a Gaussian process framework to model instrumental systematics in the light curves, and also demonstrate the use of the more generalized Student’s-T process to verify our results. We find that our measured transmission spectrum, whilst showing overall agreement, is slightly discrepant with results obtained using HST/STIS, particularly for wavelengths shortwards of ≈650 nm. In contrast to the STIS results, we find evidence for an increasing bluewards slope and little evidence for absorption from either TiO or VO in our retrieval, in agreement with a number of recent studies performed at high-resolution. We suggest that this might point to some other absorbers, particularly some combination of recently detected atomic metals, in addition to scattering by hazes, being responsible for the excess optical absorption and observed vertical thermal inversion. Our results are also broadly consistent with previous ground-based photometry and 3D GCM predictions, however, these assumed different chemistry to our retrievals. In addition, we show that the GMOS observations are repeatable over short periods (days), similar to the HST/STIS observations. Their difference over longer periods (months) could well be the result of temporal variability in the atmospheric properties (i.e. weather) as predicted by theoretical models of ultra-hot Jupiters; however, more mundane explanations such as instrumental systematics and stellar activity cannot be fully ruled out, and we encourage future observations to explore this possibility.

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Sauders, M. Gómez, M. E. Montero Cabrera, E. F. Herrera Peraza, L. Castellón Insua, K. González Labrada, and M. C. López Reyes. "Metal concentrations in scleractinean corals determined by instrumental neutron activation analysis and atomic absorption spectrometry." Journal of Radioanalytical and Nuclear Chemistry 219, no. 1 (May 1997): 135–37. http://dx.doi.org/10.1007/bf02040282.

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Hight, Susan C. "Determination of Lead and Cadmium in Ceramicware Leach Solutions by Graphite Furnace Atomic Absorption Spectroscopy: Method Development and Interlaboratory Trial." Journal of AOAC INTERNATIONAL 84, no. 3 (May 1, 2001): 861–72. http://dx.doi.org/10.1093/jaoac/84.3.861.

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Abstract This method was developed to improve sensitivity and eliminate time consuming, evaporative pre-concentration in AOAC Method 973.82 and American Society for Testing and Materials method C738 for testing foodware. The method was developed using leach solutions obtained by leaching 9 differently decorated ceramic vessels with 4% acetic acid for 24 h at room temperature. Lead and cadmium concentrations in leach solutions were 0.005–17 600 and 0.0004–0.500 μg/mL, respectively. Concentrations were determined using peak area, phosphate chemical modifier (8.3 μg PO4−3), and a standard curve for quantitation. Optimized pre-atomization and atomization temperatures were 1300 and 1800°C, respectively, for Pb and 1100 and 1700°C, respectively, for Cd. Characteristic masses (mo) were 10 and 0.4 pg for Pb and Cd, respectively. Precision of repeated analyses of calibration solutions was ≤3% relative standard deviation. Precision of duplicate leach solution analyses on different days was 0–9% relative difference. Recovery from fortified leach solutions was 96–106%. Results obtained by this method agreed 92–110% with those of confirmatory analyses. Results of certified reference material solutions agreed 94–100% with certificate values. Pb and Cd limits of quantitation (LOQ) were 0.005 and 0.0005 μg/mL, respectively. Results from 3 trial laboratories for 4 leach solutions containing Pb and Cd concentrations of 0.017–1.47 and <0.0005–0.0864 μg/mL, respectively, agreed 89–102% with results of the author. Two attributes of this method were noteworthy: (1) Background absorbance due to organic matter was entirely absent from atomization profiles, making the use of short pre-atomization hold times (2 s) possible. (2) Instrument precision was excellent and only one determination per solution was needed. Acceptance criteria for quality control measurements and a practical procedure for estimating the method LOQ during routine regulatory analyses are described.

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Babicka, Marta, Magdalena Woźniak, and Izabela Ratajczak. "Organosilanes in wood protection – chemical analysis of wood and cellulose treated with MTMOS." Annals of WULS, Forestry and Wood Technology 110 (June 30, 2020): 5–8. http://dx.doi.org/10.5604/01.3001.0014.3674.

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Organosilanes in wood protection – chemical analysis of wood and cellulose treated with MTMOS. The paper presents the results of methyltrimethoxysilane (MTMOS) reactivity with Scots pine wood and cellulose. The lignocellulosic material after treatment with ethanolic solution of MTMOS was analysed using instrumental methods – atomic absorption spectrometry (AAS) and attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). The analysis of silicon concentration in treated material indicated the presence of silane in structure of wood and cellulose. The bands characteristic of vibrations of the silicon-carbon and silicon-oxygen originating from MTMOS molecule were observed in the spectra of modified materials, which confirmed the reactivity of silane with wood and cellulose. Moreover, the chemical analysis indicated that MTMOS exhibited higher reactivity to cellulose than to pine wood.

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Rosentreter, J. J., and R. K. Skogerboe. "A Method Development for the Routine Analytical Monitoring of Aqueous Cyanide Species." Water Science and Technology 26, no. 1-2 (July 1, 1992): 255–62. http://dx.doi.org/10.2166/wst.1992.0406.

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Utilizing a highly selective reaction between silver metal and cyanide ions, an apparatus and procedure for the analytical determination of aqueous cyanide species has been developed. The rapid analysis of free cyanide has been achieved through the use of pure silver filters as the reaction medium and atomic absorption spectroscopy as the detection method. This methodology has allowed for the quantitative detection of cyanide ions down to the sub-parts-per-billion level. By incorporating selective oxidation, kinetic equilibria, and photodissociation techniques, the silver-cyanide reaction technique has been adapted to provide a means of categorically speciating aqueous cyanide compounds. The complete system has been shown to be free from common chemical interferences, including thiocyanate. This detection system provides high speed cyanide determinations with little to no sample preparation or instrument supervision.

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de Azerêdo Amaro, Joana Angélica, and Sérgio L. C. Ferreira. "Application of factorial design and Doehlert matrix in the optimisation of instrumental parameters for direct determination of silicon in naphtha using graphite furnace atomic absorption spectrometry." J. Anal. At. Spectrom. 19, no. 2 (2004): 246–49. http://dx.doi.org/10.1039/b312168b.

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Jang, Yun Jung, Jihye Lee, Kang-Bong Lee, Donghwan Kim, and Yeonhee Lee. "Quantitative Analysis and Band Gap Determination for CIGS Absorber Layers Using Surface Techniques." Journal of Analytical Methods in Chemistry 2018 (October 18, 2018): 1–9. http://dx.doi.org/10.1155/2018/6751964.

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Recently, Cu(InXGa(1−X))Se2 (CIGS) absorber layers have been extensively studied by many research groups for thin-film solar cell technology. CIGS material is particularly promising due to its exceptionally high absorption coefficient and large band gap range, which is adjustable as a function of alloy stoichiometry. To enhance the conversion performance of CIGS solar cells, understanding the CIGS structure and composition is a crucial challenge. We conducted a quantitative study to determine the bulk composition of the major elements such as Cu, In, Ga, and Se of four different CIGS photovoltaic cells. The compositional information was obtained by X-ray fluorescence (XRF), inductively coupled plasma atomic emission spectroscopy (ICP-AES), and femtosecond laser ablation inductively coupled plasma mass spectrometry (fs-LA-ICP-MS). Then, the XRF concentration ratio was compared with the intensity ratio of fs-LA-ICP-MS to investigate the potential of accurate and rapid analysis using the fs-LA-ICP-MS technique. In contrast to the bulk information, the surface techniques can supply detailed information about the chemical composition across the depth profile. Here, elemental depth distributions of CIGS thin films were investigated using magnetic sector secondary ion mass spectrometry (SIMS) and Auger electron spectroscopy (AES). The atomic distributions of four different CIGS absorber layers exhibited a good agreement although they were obtained using two different surface instruments, AES and SIMS. Comparative analysis results of different CIGS absorber layers using SIMS, AES, and fs-LA-ICP-MS provide us with the appropriate technique for the information of accurate composition in a rapid analysis time. Thanks to a simple approach using the Ga/(In + Ga) ratio, the optical band gap energy of the Cu(InXGa(1−X))Se2 quaternary layer was monitored in the entire CIGS layer. The elemental distribution and the band gap determination were then used to elucidate their relationship to the corresponding CIGS cell efficiency result.

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Kratochvil, Byron, Norine Motkosky, M. John M. Duke, and Dennis Ng. "Determination of trace aluminum concentration and homogeneity in biological reference material TORT-1 by instrumental neutron activation analysis and graphite furnace atomic absorption spectroscopy." Canadian Journal of Chemistry 65, no. 5 (May 1, 1987): 1047–50. http://dx.doi.org/10.1139/v87-177.

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The biological reference material TORT-1, lobster hepatopancreas, was analyzed for aluminum by instrumental neutron activation analysis (INAA) and graphite furnace atomic absorption spectroscopy (GFAAS). After correction of the INAA results for interferences from 28Al produced by 31P(n,α)28Al and 28Si(n,p)28Al reactions, and use of HNO3 plus HF for sample dissolution for the GFAAS analyses, the methods gave similar results of 43 ± 3 and 42 ± 2 μg/g respectively for 200 to 300-mg test portions. Analysis of six portions from each of six bottles of TORT-1 showed no statistical difference at the 95% confidence level for the between and within bottle variances. Therefore, the material can be considered homogeneous for aluminum if 200- to 300-mg test portions are taken. The variance was greater and the average lower when 30-mg test portions were analyzed for aluminum by GFAAS. The pattern of the results, together with the need for HF in the dissolution procedure, suggests the presence of aluminum-containing microparticulate mineral matter, perhaps silicate material, in the material.

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Baird, Michael J. "Analysis of an Air Conditioning Coolant Solution for Metal Contamination Using Atomic Absorption Spectroscopy. An Undergraduate Instrumental Analysis Exercise Simulating an Industrial Assignment." Journal of Chemical Education 81, no. 2 (February 2004): 259. http://dx.doi.org/10.1021/ed081p259.

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Fakayode, Sayo O., Angela G. King, Mamudu Yakubu, Abdul K. Mohammed, and David A. Pollard. "Determination of Fe Content of Some Food Items by Flame Atomic Absorption Spectroscopy (FAAS): A Guided-Inquiry Learning Experience in Instrumental Analysis Laboratory." Journal of Chemical Education 89, no. 1 (November 18, 2011): 109–13. http://dx.doi.org/10.1021/ed1011585.

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Lokhande, Ram S., Pravin U. Singare, Mahadeo L. Andhale, Raghunath Acharya, A. G. C. Nair, and A. V. R. Reddy. "Determination of macro, micro nutrient and trace element concentrations in Indian medicinal plants using instrumental neutron activation analysis and atomic absorption spectroscopy techniques." International Journal of Food Safety, Nutrition and Public Health 3, no. 1 (2010): 33. http://dx.doi.org/10.1504/ijfsnph.2010.032033.

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Mo, Zeqiang, Jin Yu, Jinduo Wang, Jianguo He, Shoujun Dai, and Yang Liu. "Differential Measurement for Cavity Ring-Down Spectroscopy with Dynamic Allan Variance." Journal of Spectroscopy 2020 (April 14, 2020): 1–13. http://dx.doi.org/10.1155/2020/8398063.

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The method of dynamic Allan variance (DAVAR) is used to analyze the time-varying characteristics of a nonstationary signal and is thus incorporated to evaluate the random error in the cavity ring-down spectroscopy (CRDS) experiments. With the numerical simulation of the influence of instabilities of sudden, slow, or periodic changes on the measurement accuracy in the ring-down process, DAVAR is proved to be an effective way to evaluate random error characteristics in an interfering environment. In order to minimize influences of time-varying noises in CRDS, a practical differential measurement method is proposed, in which wavelength modulation is applied to detect the ring-down times at the absorption peak and the nonabsorption peak in a time-division manner. The validity of the differential measurement is proved with its ability to compensate the influence of the environment changes and improves the accuracy from 0.181 ppm to 0.00914 ppm. The differential measurement method can be used to correct the time-varying error in real time and is helpful to improve the environmental adaptability of the CRDS instrument.

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Khelifa, N. "Effect of Measurement of Dew Point Temperature in Moist Air on the Absorption Line at 1392.53 nm of Water Vapor." International Journal of Optics 2019 (April 2, 2019): 1–7. http://dx.doi.org/10.1155/2019/3424172.

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The HITRAN database (High-Resolution Transmission molecular absorption database) is an extremely helpful reference for selecting lines of molecular species. In the case of water vapor, a particular strong absorption line around λ ≈ 1392.5 nm is suitable for the detection of molecules, not only because of its high strength but also because it is well separated from the neighboring transitions, thus avoiding any overlap. First, we present the optical system that uses a distributed feedback (DFB) laser diode, emitting around λ ≈ 1392.5 nm with a power ≈ 3 mW and linewidth ≤ 10 MHz. For metrological needs, we are looking for a means to control the water vapor concentration in ambient air in near real time and especially when an optical chilled mirror hygrometer is used. The latter instrument is widely used due to its performance with regard to both accuracy and repeatability of measurements. Here, using the molecular absorption device the use of such an instrument is examined from the point of view of its impact on the measurement of relative humidity. This paper reports the measured frequency positions of the observed line at λ = 1392.5337 nm for different air pressures and compares them with the values given in the HITRAN database. In addition, we discuss the possibility of using water vapor detection by spectroscopy to observe the change of the shape and the position of the absorption line produced during measurements of the dew point temperature by the optical chilled mirror hygrometer.

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Awadallah, R. M., M. K. Sherif, A. H. Amrallah, and F. Grass. "Determination of trace elements of some Egyptian crops by instrumental neutron activation, inductively coupled plasma-atomic emission spectrometric and flameless atomic absorption spectrophotometric analysis." Journal of Radioanalytical and Nuclear Chemistry Articles 98, no. 2 (April 1986): 235–46. http://dx.doi.org/10.1007/bf02037086.

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Journal articles on the topic 'Atomic absorption spectroscopy – Instruments'

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