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Hypertension is one of the leading causes of death globally and a major risk factor for different cardiovascular outcomes. This led to continuous discovery of new drugs and on-going update of drug combinations. In the present work, sustainable eco-friendly spectrophotometric methods were developed and validated for the estimation of amiloride hydrochloride (AML), hydrochlorothiazide (HCT) and timolol maleate (TIM) in their ternary pharmaceutical formulation. The proposed methods are inspired based on the unique spectral characteristics of this mixture including spectral extension of AML over both HCT and TIM spectra. AML exhibits UV maximum at 362.0 nm that permits its direct estimation by zero order spectrophotometric method without any interference in a linear range of 2.0-20 [mu]g/mL. While for the estimation of HCT and TIM, two methods were applied. The first method is dual wavelength in ratio spectra, while the second one is ratio subtraction in conjunction with the first derivative of ratio spectra method. The two methods were found linear over the concentration range of 2.0-25 [micro]g/mL for HCT and 5-80 [micro]g/mL for TIM. The suggested methods were successfully adopted for the evaluation of the studied drugs in their marketed dosage form and further implemented for content uniformity evaluation. Additionally, method greenness profile was assessed using different assessment metrics., Author(s): Hoda M. Marzouk [sup.1] , Nada S. Ayish [sup.1] , Badr A. El-Zeany [sup.1] , Ahmed S. Fayed [sup.1] Author Affiliations: (1) grid.7776.1, 0000 0004 0639 9286, Analytical Chemistry [...]

This research presents the use of deep eutectic solvents as a green and cost-effective extraction solvent in dispersive liquid-liquid microextraction of cadmium in food and environmental water specimen, where sodium diethyldithiocarbamate was employed as a complexing agent. A flame atomic absorption spectrometer was then used to quantify cadmium. The impacts of some effective variables such as deep eutectic solvent type and volume, pH, disperser solvent type and volume, diethyldithiocarbamate concentration, and extraction time were examined and optimized. Under optimal conditions, limit of detection was measured as 0.9 [mu]g/L, while limit of quantification, enrichment factor, and relative standard deviation were 2.9 [mu]g/L, 50, and 1.4%, respectively. The developed extraction method was successfully employed for Cd quantification in food and water. Recoveries of spiked samples varied in the range of 96.0-102.5%., Author(s): Mohammad Reza Jamali [sup.1] , Jamshid Mofid Nakhaei [sup.2] , Shabnam Sohrabnezhad [sup.2] , Reyhaneh Rahnama [sup.1] Author Affiliations: (1) https://ror.org/031699d98, grid.412462.7, 0000 0000 8810 3346, Department of Chemistry, [...]

Solvent as a complex environment can surround solute molecules and modify their function. In this work, different solutesolvent interaction effects on the nonlinear optical behavior of some azo dyes were studied at the molecular level. In this case, spectroscopic technique and density functional theory were used. According to the results, molecular dipole transition, changes between ground and excited state dipole moments, substituent, and environment polarity play considerable effects on the molecular nonlinear optical responses. In addition to solvent effects on the molecular first- and second-order hyperpolarizability, the two-photon absorption cross-section is also modified due to solvent-induced interactions. Moreover, the determination of the contribution of dominant solvent effects on the molecular nonlinear optical behavior can facilitate the studies on the application of optical samples in designing various optical systems. Key words: hyperpolarizability, density functional theory, spectroscopy, two-photon cross-section, 1. Introduction Optical materials with nonlinear characteristics play significant roles in optics and photonics. By exploiting basic science, researchers are active in various laboratories to synthesize materials with unique nonlinear [...]

A simple and rapid temperature induced aggregation micro extraction method based on ionic liquid for extraction and preconcentration of cobalt ions from water samples was proposed. In this investigation small amounts of 1-hexyl-3-methylimidazolium hexafluorophosphate [Hmim][[PF.sub.6]] and 1-hexyl-3-methylimidazolium fc-(trifluoromethylsulfonyl)imide [Hmim][[Tf.sub.2]N] (as extractant solvents) were added in a sample solution containing Triton X-114 (as an anti-sticking agent). After centrifuging the cooled solution, analysis was carried out by flame atomic absorption spectrophotometry. Some effective parameters have been optimized. Under the optimum conditions, detection limit of the method was 0.44 ng/mL and the relative standard deviation (RSD) for 100.0 ng/mL cobalt was ± 2.3% (n = 7).The calibration curve was linear in the range of 3.0 - 200.0 ng/mL cobalt and enrichment factor was obtained as 26.5. The applicability of the technique was evaluated by the determination of trace amounts of cobalt in several water samples and synthetic alloys. Keywords: liquid phase micro extraction, cobalt, ionic liquid, temperature-induced aggregation, flame atomic absorption DOI: 10.1134/S1061934814060112, Cobalt is an essential micronutrient for humans, animals and plants for a range of metabolic process or some biochemical metalloenzyme reactions [1, 2]. Cobalt acts as the central atom of [...]

Cold-induced aggregation microextraction (CIAME) combined with flame atomic absorption spectrometry (FAAS) was applied to preconcentration and determination of nickel(II) ions in natural water samples. The proposed method used 1-hexyl-3-methylimidazolium hexafluorophosphate ([Hmim][PF6]) as the extraction solvent and 1-(2-thiazolylazo)-2-naphthol (TAN) as the complexing agent. The extraction solvent was dissolved in the sample solution at 45°C. After dissolving, the solution was cooled in the ice bath and a cloudy solution of IL fine droplets was formed due to the decrease of IL solubility. After centrifugation, the fine droplets of extractant phase were settled at the bottom of the conical-bottom centrifuge tube. Analysis was carried out by a FAAS. Several important parameters influencing the CIAME extraction efficiency such as pH, complexing agent concentration, extraction solvent volume, salt effect, solution temperature, extraction time, centrifugation time and heating time were investigated and optimized. Under the optimum conditions, the limit of detection (LOD) was 0.8 ng/mL, and the relative standard deviation (RSD) was 3.4% for 50 ng/mL of nickel. The performance of the method was evaluated for extraction and determination of nickel in tap, mineral and seawater samples, and satisfactory results were obtained. Keywords: ionic liquid, cold-induced aggregation microextraction, flame atomic absorption spectrometry, nickel DOI: 10.1134/S1061934814050062, The pollution of natural waters by heavy metals is a great concern nowadays due to their potentially toxic effects on living organisms. Urbanization, industrial development, and heavy traffic lead to [...]

Sorghum-agricultural waste in nature (SAWN) and chemically activated with phosphoric acid (SAWAC) was used as a solid phase extraction material for determination of cadmium, copper, manganese and lead ions in aqueous solutions by flame atomic absorption spectrometry (FAAS). The effect of pH, sample flow rate and volume, eluent type, volume and flow rate, and the effects of potentially interfering ions on the recovery of the analytes were investigated. Adsorption capacity of SAWN and SAWAC was determined by batch method under the optimized conditions. Adsorption capacity of SAWAC was found to be 9.53, 11.77, 11.64, and 15.01 mg/L for Cd, Cu, and Mn and Pb ions, respectively. The limit of detection (LOD) for the analytes was found in the range of 0.16-1.21 µg/L with a theoretical preconcentration factor of 50. The method was validated by analyzing certified material (GBW 07605--Tea) and the results were in a good agreement with the certified value. In addition, the proposed method was applied to the determination of analytes in tea and river water samples. Keywords: sorghum-agricultural waste, solid phase extraction, heavy metals, flame atomic absorption spectrometry DOI: 10.1134/S1061934814050098, The heavy metals originate from industrial activities (metal plating, mining, smelting, battery, paint, and pigment manufacture, tanneries, petroleum refining, pesticides, pigment manufacture, printing and photographic industries, etc.) and agricultural activities [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2009.05.017 Byline: Marija Jakubeniene (a), Algimantas Irnius (b), Gregoire Abi Chaker (a), Jonas Mindaugas Paliulis (a), Antanas Bechelis (a) Keywords: Forensic medicine; Hypothermia; Calcium; Atomic absorption spectroscopy Abstract: The identification of hypothermia as cause of the death was always quite problematic in the field of forensic medicine. The aim of the present study was to verify the determination of calcium content in post-mortem liver, heart, and skeletal muscle samples as the biochemical marker defining hypothermia as the cause of death. The study involved 43 autopsy cases in which the circumstances of death indicated the effects of overcooling. The control group consisted of material collected from the corpses of 30 persons who were not exposed to low temperatures but died due to technical injuries (n =5), asphyxia (n =6), intoxication with ethanol and other substances (n =8), and acute myocardial infarction/ischemia (n =11). The concentration of calcium in autopsy samples was determined applying flame atomic absorption spectroscopy. Our study showed no significant differences of calcium content in tissues of persons who died due to hypothermia, over those who died in normothermic conditions. Author Affiliation: (a) Institute of Forensic Medicine of Mykolas Romeris University, Didlaukio str. 86E, Vilnius LT-08303, Lithuania (b) Vilnius University, Universiteto 3, Vilnius LT-01513, Lithuania Article History: Received 15 December 2006; Revised 18 March 2009; Accepted 25 May 2009

The H-F stretching band in the absorption spectrum of [[C[H.sub.3]].sub.2]O...HF in the gas phase is examined. Strong intermolecular interaction is observed in the [[C[H.sub.3]].sub.2]O...HF complex.

Diode laser transient absorption spectroscopy was used for examining the relaxation of highly vibrationally excited 1,2-, 1,3-, and 1,4-difluorobenzene (DFB) by collisions with carbon dioxide. Large amounts of rotational and translational energy transfer from the hot donors to the bath were observed.

The infrared and electronic absorption measurements of the radical anion and dianion of p-terphenyl in an inert gas glovebox system are discussed. Findings reveal that the strong infrared intensities of the radical anion and dianion are a result of charge fluxes generated by electron-vibration interactions.

Subpicosecond absorption spectroscopy is used for characterizing primary photoinduced processes in a class of push-pull polyenes bearing a julolidine end group as the electron donor and a diethylthiobarbituric acid end group as the electron acceptor. The results have shown that photoinduced reaction trajectories in push-pull polyenes are controlled by the static and dynamic properties of the solvent, the chemical nature and size of the end groups and the conjugated-chain length and flexibility.

A diode-laser-based sensor has been developed to measure nitric oxide mole fractions using absorption spectroscopy. The sensor is based on sum-frequency mixing of a 395 nm external-cavity diode laser (ECDL) and a 532 nm laser in a beta-barium-borate crystal. Using a new tuning scheme, the GaN ECDL wavelength was modulated over 90 GHz without mode hops. The sensor was applied for measurements of the NO mole fraction in the exhaust of a laboratory-scale, 30 kW, coal-fired boiler burner. Absorption measurements were successfully performed despite severe attenuation by scattering from ash particles in the exhaust stream and on the exhaust-section windows. A detection limit (1[sigma]) of 4.5 ppm m[sqaure root of (Hz)] at 700 K was demonstrated in coal-combustion exhaust at a maximum detection rate of 5 Hz. OCIS codes: 300.1030, 300.6260, 300.6540, 280.1120, 120.1740, 140.2020.

Abstract -- The use of ram horn powder (RHP) as a new sorbent for the preconcentration of copper(II) was proposed. The procedure is based on the adsorption of copper(II) ions [...]

Abstract -- A simple and useful method employing cloud point extraction is proposed for the preconcentration and separation of silver in water samples. The silver cation reacts with bis(2-mercaptoanil) acetylacetone [...]

Abstract -- The complexation of vanadium(V) with 2-hydroxy-5-t-butylphenol-4'-methoxyazobenzene was studied. Optimum complexation conditions were found. The main spectrophotometric parameters of the resulting complexes were determined. A procedure was developed for [...]

Byline: M. A. Amaro Lopez (1), R. Moreno Rojas (1), G. Zurera Cosano (1) Keywords: Macroelements; Trace elements; Atomic absorption spectrometry; Green asparagus; Frozen storage Abstract: The contents of macroelements (Ca, Mg, Na, K y P) and trace elements (Cu, Fe, Zn and Mn) of frozen green asparagus were determined by atomic absorption spectrometry to investigate the possible changes during 45 and 90 days frozen storage at -18 degC. A significant decrease of mineral concentrations was observed at 45 days of frozen storage. After 90 days, modifications were not observed, except for Cu and P concentrations. The asparagus thickness factor resulted in significant differences in the Cu, Fe, Zn, Ca and K contents. Frozen storage time involved smaller percentages of mineral retention in the &lt 11 mm spear for Ni, Ca, Mg, K and P, and, for the rest of mineral elements, the frozen storage effect was similar for both thicknesses (&lt 11 mm and &gt 14 mm). The highest mineral concentration was found in the apical portion or tip of green asparagus, except for Mn, Cr and K. Mineral retention percentages after frozen storage time were similar in both portions (apical and basal) of the spear. Author Affiliation: (1) Department of Food Science and Technology, University of Cordoba, Campus Universitario de Rabanales, Edificio Darwin, 14014, Cordoba, Spain Article History: Registration Date: 02/04/2004 Received Date: 06/02/2004 Online Date: 30/06/2004

Byline: A. B. Volynskii (1) Abstract: Mechanisms of the action of chemical modifiers based on platinum-group metals have been considered. It has been shown that the efficiency of a chemical modifier is determined mainly by chemical processes occurring at the pyrolysis step. By combining the results obtained using different methods, these processes have been described step-by-step. The systematic study of Pd, Pt, Rh, Ru, and Ir in chloride and sulfate media as chemical modifiers has revealed a correlation between the relative efficiencies and some chemical properties of the modifiers. It has been shown that, in the presence of matrices weakly interacting with platinum-group metals (for example, sodium chloride), the best modifiers are metals that most intensely interact with the analytes (ruthenium and iridium in determining metalloids). However, if the chemical modifier strongly interacts with the sample matrix, the efficiency of the modifier is determined by the interaction processes. For example, in the presence of a sulfate matrix capable of reacting with platinum-group metals, the best modifier is palladium. The correlations found may be useful for the practical application of platinum-group metals as chemical modifiers in the analysis of complex samples by electrothermal atomic absorption spectrometry. Author Affiliation: (1) Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, ul. Kosygina 19, Moscow, 119991, Russia Article History: Registration Date: 06/10/2004

Byline: Angeles Jos (1), Isabel Moreno (1), A. Gustavo Gonzalez (2), Miguel Lopez-Artiguez (3), Ana Maria Camean (1) Keywords: Brut cava; Metals; ICP; AAS Abstract: The aim of this study was to investigate the content of several metals in different commercial sparkling wines, all of them with the denomination of origin 'cava', in order to characterise them. Sixteen metals were determined in 18 samples of cava by inductively coupled plasma atomic-emission spectrometry (ICP-AES), hydride generation atomic-absorption spectrometry (HG-AAS) and graphite furnace atomic-absorption spectrometry (GF-AAS). Al, Ba, Ca, Cu, Fe, K, Mg, Mn, Na, P, Sr and Zn were analysed by ICP-AES HG-AAS was employed for As quantification and GF-AAS for Ni, Cd and Pb analysis. The procedure involved the degasification of the cava sample by sonication, followed by [H.sub.2]O.sub.2/[H.sub.2]SO.sub.4 treatment and heating in an oven. Author Affiliation: (1) Area de Toxicologia, Facultad de Farmacia, Universidad de Sevilla, C/ Profesor Garcia Gonzalez no.2, 41012, Sevilla, Spain (2) Departamento de Quimica Analitica, Universidad de Sevilla, Spain (3) Instituto Nacional de Toxicologia, Apdo. Correos 863, 41080, Sevilla, Spain Article History: Registration Date: 13/01/2004 Received Date: 08/09/2003 Online Date: 03/02/2004

Byline: Farzaneh. Shemirani (1), Masood. Salavati Niasari (2) Abstract: A method for the preconcentration of Cd(II), Cu(II), Zn(II), and Ni(II) is proposed using a minicolumn filled with silica gel modified by Schiff's base. The retained analytes on the ligand-coated silica gel were recovered with a small volume of HNO.sub.3 (nitric acid). The metal ions in the eluent were determined by flame atomic absorption spectrometer (FAAS). Different factors, including the pH of the sample solution, the sample volume, the amount of silica gel, eluent volume and matrix effects for preconcentration were examined. The recoveries for the analytes under optimum working conditions were higher than 95%. The relative standard deviations of the determination were 1.50, 2.10, 2.40, 3.43% for Cu(II), Cd(II), Zn(II) and Ni(II). The limits of detection (3s, n = 10) for Cd(II), Cu(II), Zn(II), and Ni(II) were found to be 3, 5, 5 and 4.7 ngL.sup.--1. The proposed method was applied to the analysis of some natural water samples and standard reference aluminum alloy material (NBS SRM 85b). Author Affiliation: (1) Department of chemistry, Faculty of Science, University of Tehran, IRAN (2) Department of chemistry, Faculty of Science, University of Kashan, IRAN Article History: Registration Date: 06/10/2004

Byline: A. V. Voloshin (1), A. Kh. Gil'mutdinov (1), Yu. A. Zakharov (1), A. A. Sevast'yanov (1) Abstract: Shadow spectral filming is used to study the spatiotemporal dynamics of the formation and dissipation of vapors of potassium sulfate and aluminum and indium nitrates in a transversely heated graphite furnace atomizer. The integrated platform, the Pd--Mg modifier, the internal flow of the sheath gas, the magnetic field of the nonselective background corrector, and the diffusion of oxygen from the ambient air are responsible for specific nonuniformities in the spatial structure of the vapor cloud. The nonuniformities result to a large extent from the transverse nonisothermal conditions of the graphite furnace. The explosive splashes of aluminum vapors interfering with the analysis are generated at the cold side walls of the graphite furnace, where the vapors are condensed in the process, rather than on the particles of the dry residue of the sample. The beating of the magnetic-field induction inside the graphite furnace atomizer caused by the overlapping of the fields of the heating current (50 Hz) and the background corrector (54 Hz) results in low-frequency (4--5 Hz) oscillations of the spatial position of the vapor cloud. The matrix modifier can stimulate these oscillations. Author Affiliation: (1) Physics Faculty, Kazan State University, Kremlevskaya ul. 18, Kazan, 420008, Russia Article History: Registration Date: 06/10/2004

The reactions of 2H-heptafluroropropane with O[(super 3)P] and H atoms are examined at high temperatures by using a shock tube technique coupled with atomic resonance absorption spectroscopy. The results were in agreement with the G2(MP2) energy barriers, within the expected uncertainty.

The population relaxation rate is examined of the first excited state of the acetylenic C-H stretch that is compared for room-temperature gas-phase and solution-phase samples of 10 terminal acetylenes. It is observed that a single solvent relaxation contribution to the total relaxation rate describes the solution dynamics for all terminal acetylenes which is consistent with the idea that solvent-induced energy relaxation pathways are dominated by the vibrational motions that are in close proximity to the excited state.

Abstract -- The dynamic of the formation and dissipation of sodium and nickel chloride vapors in the THGA transversely heated graphite furnace atomizer of a SIMAA 6000 multielement spectrometer was [...]

The black-dye/TiO2 system by electronic absorption and vibrational spectrocopies are characterized. The FT-IR spectroscopic data reveal that black-dye molecules are bound to the Tio2 surface via a bidentate binuclear coordination.

The effects of high-pressure (up to 1015 MPa) on exitonic coupling energies and energy disorder in the light harvesting complex 2 (LH 2) from rhodopseudomonas acidophila (strain 10050) were studied. The low-temperature (5 K) nonphotochemical hole burning and adsorption spectroscopies were used to study the process.

Tim Shelbourn (*) Baxter Healthcare The ultratrace aluminum analysis of two nutritional intravenous solution components with limited water solubility can be performed by GFAAS with dissolution in 1-propanol. Use of […]

Byline: Rudy Van Cauwenbergh (1), Peter Hendrix (1), H. J. Robberecht (1), Hendrik A. Deelstra (1) Keywords: Key wordsaSodium; Potassium; Belgium; Dietary intake Abstract: aThe daily dietary sodium and potassium intakes in Belgium were evaluated by sampling duplicate portions of food, destruction in a microwave oven and their sodium and potassium contents determined by atomic absorption spectroscopy. The mean intake for sodium (4.15+-1.01g/day) was found to be similar to values found in most other countries but well above the recommended range set by the National Research Council of the USA and the range established for Belgium. The mean intake for potassium (3.39+-0.84g/day) was somewhat higher than values for other countries and also above the recommended range for Belgium but not for the USA. Author Affiliation: (1) Department of Pharmaceutical Sciences, University of Antwerp (UIA), Universiteitsplein 1, B-2610 Antwerp, Belgium, BE Article note: Received: 24 June 1998

Byline: H. Robberecht (1), Peter Hendrix (1), Rudy Van Cauwenbergh (1), Kristien Van Dyck (1), Hendrik Deelstra (1) Keywords: Key wordsaBelgium; Minerals; Trace elements; Vegetarian foodstuffs; Atomic absorption spectrometry Abstract: aAtomic absorption spectrometry was used to determine mineral (Na, K, Ca and Mg) and trace element content (Zn, Fe, Cu and Si) of various vegetarian foodstuffs in Belgium. Thirty-five commercially available products were analysed after a wet-acid destruction in a closed-vessel destruction bomb. Various important sources of the minerals and trace elements were identified. Since data for vegetarian foods in Belgium are non-existent, the concentration values are compared with the scarce literature data and particularly with levels found in the same products available in The Netherlands. Author Affiliation: (1) Laboratory of Food Sciences, Department of Pharmaceutical Sciences, University of Antwerp (UIA), Universiteitsplein 1, B-2610 Wilrijk, Belgium, BE Article note: Received: 2 June 1998 / Revised version: 5 October 1998

Research was conducted to examine the electronic absorption spectrum of the hexamethyl(Dewar benzene) radical cation. Samples were prepared by immersing room-temperature solutions in liquid nitrogen. Photochemical reactions were performed with a 450 W xenon arc lamp as a light source. Results based on the distribution of reaction rates clearly suggest that the activation barrier for the process is strongly influenced by environmental factors.

The crystal structure of human endostatin reveals a zinc-binding site. Atomic absorption spectroscopy indicates that zinc is a constituent of both human and murine endostatin in solution. The human endostatin zinc site is formed by three histidines at the N terminus, residues 1, 3, and, 11, and an aspartic acid at residue 76. The N-terminal loop ordered around the zinc makes a dimeric contact in human endostatin crystals. The location of the zinc site at the amino terminus, immediately adjacent to the precursor cleavage site, suggests the possibility that the zinc may be involved in activation of the antiangiogenic activity following cleavage from the inactive collagen XVIII precursor or in the cleavage process itself.

Byline: Janos Vetter (1), Erzsebet Berta (1) Keywords: Key wordsaMercury; Wild edible mushrooms; Atomic absorption spectrometry; Agaricus; Macrolepiota; Lepista; Lycoperdon perlatum Abstract: aThe mercury (Hg) content of 112 samples of common, wild edible mushrooms was analysed by atomic absorption spectrometry. The average Hg content of all the samples was 1.72 mg/kg dry mass (DM) but the Hg concentrations found in different taxonomic groups (genera and species varied) remarkably. Although different sampling locations obviously have an effect on the Hg concentration of sporocarps, we found evidence for a Hg-accumulating capacity of some taxonomic groups. In addition to Agaricus and Macrolepiota, where the phenomenon of mercury accumulation has already been described, our results indicate high Hg levels in samples of Lycoperdon perlatum (average 2.94 mg/kg DM) and in Lepista species (average 3.02 mg/kg DM). These data confirm the need for greater attention to be given to Hg levels in wild common mushrooms, especially to Hg-accumulating species. Author Affiliation: (1) Department of Botany and Biological Laboratory, University of Veterinary Science, P.O. Box 2, H-1400 Budapest, Hungary, HU Article note: Received: 20 February 1997

A longitudinal study was conducted to evaluate the relationship between the level of zinc in maternal milk and the nutritional status of gestating mothers during the third trimester of pregnancy. The results confirmed that diet affects the maternal milk zinc levels during pregnancy and those of milk during lactation. While it has been established that zinc in the diet is quite important in maintaining the health of gestating mothers, there is still a need to pursue further studies to warrant the modification of the current recommended intake of zinc.

Self-injection control was shown to be effective in producing efficient, narrow line, two-wavelength emission in a CW Ti3+ :Al2O3 laser. The two-wavelength selector is a combination of an interference wedge and a grazing incidence grating. To avoid insertion losses and optical damage problems, the device operates outside the main nonselective laser cavity. This produced two independently tunable two narrow laser lines of total output power of 1.5 watts, which can be emitted separately or as a single beam.

Measurements of the ratio of heat produced to energy absorbed provide an alternative to other heat load characterization of solid-state laser media. This method is convenient as only temperature and pump energy are recorded. This involves only energy defect and non-radiative quenching and provides the same results as spectroscopy and through calculations indicating strong consistency between heat characterization and laser characterization.

Protein affinity and gel-filtration experimental studies and atomic absorption spectroscopy of the mutant zinc-finger domain of human transcription factor IIE (TFIIE) reveal that the large subunit of TFIIE, TFIIE-56, functions as a zinc binding protein that is essential for the TFIIE activity. Mutant TFIIE-56 combines with small subunit TFIIE-34 to develop into a stable heterotetramer. Gel mobility shift experiments show that transcription inhibition by mutant TFIIE indicate the mutant's inefficiency in assembling a stable transcription complex. Zinc binding by TFIIE results in a specific structure that aids the transcription complex development.

Byline: D. G. Filatova (1), L. N. Ryazanova (2), O. A. Shiryaeva (2), N. B. Zorov (1), Yu. A. Karpov (2) Abstract: The conditions for the formation of soluble complex gold ammines were considered for the subsequent determination of gold by atomic absorption spectrometry with a graphite atomizer. It was found that complex ammine solutions of pH 9--11 were stable at gold concentrations to 25 +- 5 ug/mL in the test solution and that the ashing temperature could be increased to 1200degC. Author Affiliation: (1) Department of Chemistry, Moscow State University, Vorob'evy gory, Moscow, 119992, Russia (2) Giredmet Research and Project Institute of Rare Metals Industry, Bol'shoi Tolmachevskii per. 5, Moscow, 109012, Russiay Article History: Registration Date: 06/10/2004

The use of united atom force field for accurate reproduction of the adsorption properties of alkanes in nanoporous framework structures is analyzed. It is concluded that it reproduces extremely well heats of adsorption, entropies of adsorption and maximum loading.

The influence of orientation of perylene-3,4-dicarboximide (PMI) on triplet energy transfer (TET) rates is discussed. The synthesis of the linear arrays of zinc meso-tetraarylporphyrin (ZnP), perylene-3,4-dicarboximide (PMI) with naphthalene-1,8:4,5-bis(dicarboximide) (NI) and pyromellitimide (PI) is examined with the help of ultrafast transient absorption spectroscopy.

A study was conducted to investigate the reaction mechanism of O + COS -> products. Time-resolved measurements of O and S atoms were conducted by using atomic resonance absorption spectroscopy, and the overall rate constant was determined by the O atom decay at temperatures 1250-1600 K.

Electronic absorption spectroscopy is used for the study of complexes of fullerene C70 with aniline and various substituted anilines in CCl4 medium. It has been observed that C70 acts as a better acceptor than C60 does in forming charge transfer (CT) complexes and the degree of charge transfer in the ground state of the complexes has been found to be very low (0.2--0.3%).