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[en] Complete text of publication follows. In order to count on biomaterials that can be used as implants or osseous fillings, with properties similar to the physiological weave with which they interact and fluids with which they are in contact, it is necessary to make sure that their properties are nearest to each other. Therefore the knowledge of the physical properties as the optical contributes very important information to us that it helps us in the election of biomaterials used in osseous implant. In the present work by means of the technique of Photoacoustic Spectroscopy the optical absorption spectrum of used synthetic and natural materials like osseous substitutes are obtained. The optical rank of observed absorption went of 300 to 800 NM.
[en] Complete text of publication follows. The focus of this work is on the post-breakdown plasma model (I.B. Gornushkin, S.V. Shabanov, N. Omenetto, J.D. Winefordner, J. Appl. Physics 100 (2006) 073304). The model is based on the conventional fluid dynamic equations supplemented by the equations of state and radiative transfer. It is used to solve the inverse initial value problem and to determine the plasma composition from the measured plasma spectrum. This is realized through the Monte Carlo procedure where the initial plasma parameters are iterated until a good agreement is achieved between the calculated and experimental spectra. This approach is aimed at finding a solution for calibration-free analysis. A comparison between different calibration-free methods will also be presented.
[en] Complete text of publication follows. X-ray fluorescence spectrometers become as small as a handy instrument, but the sensitivity is comparable to a big instrument. Only the difference may be the precision of the spectrometer. We have developed small size total reflection X-ray fluorescence (TXRF) spectrometers with the detection limit of a few tens of pico grams, with an X-ray tube of several watts. The key techniques will be discussed from the following points. 1. X-ray wave guide, 2. music recording of X-ray spectra, 3. monochromatic or non-monochromatic excitation, 4. the relation between sample total amount and the detection limit, 5. the relation between X-ray intensity and the detection limit. The present research was financially supported by JST SENTAN as well as JSPS Research Fellowships for Young Scientists (SK).
[en] Complete text of publication follows. A detailed study of the relevant analytical figures of merit for time-integrated multi-pulse laser-induced breakdown spectroscopy (MP-LIBS) was performed. Sensitivity, repeatability, linear dynamic range and limits of detection, when using air and argon atmospheres, were studied for several elements in solid and liquid samples and compared to the figures of single-pulse LIBS. Laser bursts containing up to 6, ns-range duration laser pulses, separated by s-range interpulse gaps were used in the experiments, and the effect of the number of pulses within the burst on the analytical parameters was also investigated. For the analysis of liquid samples, various approaches of liquid-to-solid matrix conversion were applied. The results indicate that, depending on the experimental conditions, the multi-pulse approach can provide a significant improvement in the analytical capabilities of LIBS.
[en] Complete text of publication follows. The concept of nascent hydrogen is as old as the discovery of hydrogen. The term itself is derived from the Latin 'nasci' (to be born) and was introduced by Joseph Priestley no later than in 1781. Hydrogen 'in the nascent state' was initially created as a term for hydrogen being set free from its compounds by the action of, say, a metal and acid. Yet, there are plenty of inherent assumptions - the hypothesis that at the very moment of their liberation, the elements exist in the 'elastic' state; that somehow the activity of an element is greatest at the instant of liberation from its compounds. This doctrine, with few modifications, has found wide acceptance virtually among all chemists and still persists. Otto Wallach (1910), Paul Sabatier (1912) and Frederic Joliot (1935) all use the term 'nascent hydrogen' in their Nobel lectures. In this presentation the history and evolution of the nascent concept will be discussed.
[en] Complete text of publication follows. This presentation will focus on new tools that are being developed for the practice of mass and optical spectrometry. For use in mass spectrometry, novel spectrometers and detectors will be featured, while for optical spectroscopy, a new emission source applicable to environmental analysis will be evaluated. One mass spectrometer that will be described is intended to accept two sources at the same time, in a truly simultaneous fashion. Another enables an entire mass range to be detected at once, so efficiency, speed, and precision are improved, while spectral skew is avoided. The emission source to be described is intended for field applications. It offers detection limits that rival those from the ICP, but requires only a 60Wdc power supply, no flowing gases, and can use a relatively simple monochromator.
[en] Complete text of publication follows. Trace metals have been determined by AAS after sample digestion with a vast number of reagents from nitric acid alone to combinations of nitric acid with peroxide or hydrofluoric, sulfuric and hydrochloric acids. In marine biota samples many elements are decomposed successfully, when only nitric acid is used to their microwave digestion. In this study a comparison of two digestion methods (nitric acid and nitro-hydrochloric combination) was made for the total decomposition of mollusc samples prior to their metal analysis by atomic absorption spectrometry (AAS). When silver was analyzed, the mixture of hydrochloric and nitric acids was necessary for samples with high silver concentrations (more than 1 mg/kg, dry weight). Additionally, this study reveals that if that acid mixture digestion is used prior other metals determination, low recoveries were obtained for As.
[en] Complete text of publication follows. The solvent dependent dual fluorescence of 4-dimethylaminobenzonitrile (DMABN) originated from a locally excited state (LE) and twisted intramolecular charge transfer (TICT) state that is stabilized in polar solvents. It has been the subject of intense experimental and theoretical work since its discovery in 1959. It can be expected that DMABN can form a halogen-bonding complex with a halogen atom as Fig. 1. Herein the fluorescence of DMABN alone and with carbon tetrabromide (CBr4) or diiodoperfluorohexane was investigated in different solvents. Upon addition of CBr4 or diiodoperfluorohexane, both LE and TICT peak decreased, but TICT peak decreased more sharply, as showed in Fig. 2. The halogen-bonding may disturb the TICT state by CT between Br and N atom. Also Br quenches dual fluorescence by heavy atom effect. So fluorescence from TICT state decreased more quickly than that from LE state.
[en] Complete text of publication follows. This work is aimed at demonstrating the potential of the implementation of automatic flow systems in solid-phase spectroscopy (SPS); with this purpose, two automatic systems have been employed, multicommutation and sequential injection analysis (SIA) and a critical comparison of both methodologies has been performed. The implementation of chemiluminescence detection in SPS has been satisfactorily carried out in both methods: a model analyte, 5-aminosalicylic acid, has been selected and it has been determined making use of its chemiluminescence reaction with permanganate retained on a solid support. First, the study of the most appropriate commercial flow-through cell and the optimum conditions for the reaction was performed. Second, the main differences in terms of flow variables and analytical parameters for multicommutation and SIA are stated. Finally, the analyte was determined in pharmaceuticals; in addition, statistical tests were carried out to prove the accuracy of the recovery method and to test that there is no significant difference between the two proposed methods with regard to accuracy and precision.
[en] The CSI36 conference will be held at the ELTE Convention Centre. In accordance with traditions, the programme consisted of invited plenary and keynote lectures, as well as oral and poster sessions. The scope of the conference, which encompasses the following fields of spectroscopy: Atomic plasma spectrometry (ICP, GD, AAS, etc.); Molecular spectrometry (UV-Vis, NMR, Raman, IR, etc.); Organic and inorganic mass spectrometry (TIMS, MALDI, LC-MS, GC-MS); X-ray spectrometry (XRF, XRD, XANES, PIXE, etc.); Hyphenated techniques; Laser spectroscopy; Imaging techniques; Nuclear techniques (Moessbauer spectroscopy, gamma spectroscopy, NAA); Quality control and chemometry. Contributions describing applications of the above spectroscopy techniques are also highly encouraged, such as in the area of: Material sciences (micro, surface and interface analysis); Environmental and geochemical analysis; Archaeometry and cultural heritage; Biological applications; Food analysis; Clinical and pharmaceutical analysis; Speciation; Mass spectrometry in post-genomics and proteomics; Miniaturisation and nano-technology. (S.I.)