bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and Simulation of a Trap-Based Pulsed Slow Positron Beam
Authors: He Chun Qing , Wang Jun Cheng , Zhu Jun , Wang Shao Jie
Published: November 2012

A simple pulsed slow positron beam based on a Penning-trap has been designed and is being constructed in Wuhan University. The cooled positrons from the trap with very low energy dispersion are dumped and chopped to pulses of a few tens of ns in width. Positron pulses are bunched by adjusting the potential of drift tube using an arbitrary wave generator, then accelerated to the target. Influences of the pulse width, the energy dispersion of positrons etc. on the time resolution of bunched positron pulse are simulated. The result shows that lower energy dispersion of positrons leads to much narrower positron pulses, indicating that a trap-based slow positron beam has a great advantage in developing a pulsed slow positron beam.
Positron Annihilation Spectroscopy at LEPTA Facility
Authors: Sidorin Aleksey A. , Meshkov Igor , Ahmanova E. , Eseev M. , Kobets A. , Lokhmatov V. , Pavlov V. , Rudakov A. , Yakovenko S.
Published: November 2012

The Low Energy Positron Toroidal Accumulator (LEPTA) at JINR proposed for generation of positronium in flight can be used for positron annihilation spectroscopy (PAS) [1]. The positron injector of the LEPTA facility can generate continuous a slow positron beam with the intensity up to 1∙107s-1 at the energy in the range of a few eV to 100 keV and width of the spectrum 1 – 2 eV. The injector is based on radioactive 22Na isotope. The solid neon is used as a moderator to generate monochromatic beam. The parameters of the positron beam allow scanning the condensed matter in depth up to 10 microns with resolutions less than 10 nanometers and investigating layered structures for microelectronics and properties of a surface.
Positronium in Normal Alkanes
Authors: Goworek Tomasz , Zgardzińska Bożena , Pietrow Marek , Wawryszczuk Jan
Published: November 2012

A review of data about positron annihilation lifetime in normal alkanes is presented. It was found that positronium in rigid phase locates in the interlamellar gap, while in the rotator one in free volumes inside lamellae. Interesting effects seem to be: identity of o-Ps lifetime in rotator and liquid phase in long chain alkanes; appearance of “premature” rotator phase in nonadecane with low tricosane admixture, long-term relaxation after the changes of temperature or pressure in some binary mixtures, formation of porous structure at solidification of argon saturated alkane under high pressure.
Encapsulation of Natural Flavors in Cyclodextrins: Free Volume Studies by PALS
Authors: Ferreira Marques Maria Fatima , Gordo P.M. , Santos S.D. , Marques R.F. , da Silva A. Moreira , Kajcsos Z.
Published: November 2012

Positron annihilation lifetime spectroscopy (PALS) is used to study the free-volume in β-cyclodextrin (CD) with the encapsulation of two different essential oils: garlic (Allium sativum) and marjoram (Origanum majorana). The data reveal the presence of a long lifetime component related to the o-Ps. It is observed that the addition of garlic (or marjoram) oil to β-CD results in a decrease of the o-Ps lifetime which was ascribed to a reduction of the free volume holes from 83.6 to 67.7 Å3 (79.1 to 72.6 Å3). Different mechanisms for the encapsulation of garlic and marjoram oils in β-CD are suggested by the PALS parameters.
Crystal Structure of Hf2GaSb3
Authors: Tokaychuk Iryna , Tokaychuk Yaroslav , Gladyshevskii Roman E.
Published: November 2012

The structure of the new ternary compound Hf2GaSb3 was determined by means of X-ray powder diffraction. It crystallizes with the structure type Zr2CuSb3 which represents a ternary ordered derivative of the UAs2 type (Pearson symbol tP6, space group P-4m2, a = 3.89841(8), c = 8.62650(19) Å). The ternary compound can be regarded as an ordered, Ga-stabilized derivative of the high-temperature modification of the binary antimonide HfSb2 (structure type UAs2).
Bulk Synthesis and Structural Determination of High Mobility Multication Transparent Conducting Oxides
Authors: Jayaram Peediyekkal , Jaya T.P. , Pradyumnan P.P.
Published: November 2012

This work reports the synthesis of novel quaternary transparent conducting oxide Cd(1-x)Sn(1-x)InxGaxO3( x=0.1, 0.2, 0.3) at 1225°C via solid state reaction route. The investigations on structural, optical and electrical properties have been carried out. Powder X-ray diffraction revealed the phase purity and distorted orthorhombic structure of the species synthesized. Distortion of the structure is due to the substitution of In3+ and Ga3+ in CdSnO3 (JCPDS card no.340885) matrix. The optical transmittance approximated by the reflectance shows considerable increase in the transmittance of visible light along with the increase of substitution. Typical Burstein-Moss effect is observed with the increase in x value as a variation in optical bandgap from 2.7 to 2.9eV. Four point Hall measurements by Van der-Pauw method exhibit superior properties in charge carrier concentration and mobility. Maximum bulk charge concentration of 4.78x1017 cm-3 is obtained for x=0.3. Hall mobility depends on carrier concentration and steeply increases with the carrier concentration. Considerable drop in the resistivity of the material along with higher transmittance is a critical finding in the experiment.
Deposition and Characterization of Nanostructural IrOx by RF Sputtering
Authors: Tiong Kwong Kau , Lin Cheng Hsien , Chen Yi Min , Huang Ying Sheng , Lee Kuei Yi , Tsai Dah-Shyang
Published: November 2012

Large surface area nanostructural IrOx films were deposited on stainless steel substrates by reactive radio frequency magnetron sputtering using Ir metal target. The structural and spectroscopic properties of the nanostructural IrOx were characterized. The micrographs of field emission scanning electron microscopy showed the formation of folded leaves with chiffon-like structure for the as-deposited samples. X-ray photoelectron spectroscopy analysis provided the information of the oxidation states and the stoichiometry of IrOxNL. Raman spectra revealed the amorphous-like phase of the as-deposited nanostructural IrOx. The chiffon-like structure provides ultra-high surface area for electrical charge storage which makes the IrOxNL as an attractive candidate for the supercapacitor application.
Structural and Band-Edge Properties of Cu(AlxIn1-X)S2 (0≤x≤1) Series Chalcopyrite Semiconductors
Authors: Ho Ching Hwa , Pan Chia Chi , Cai Jian Rong , Huang Guan Tzu , Dumcenco Dumitru O. , Huang Ying Sheng , Tiong Kwong Kau , Wu Ching Cherng
Published: November 2012

We have demonstrated structural and electronic properties of a series solar energy crystals Cu(AlxIn1-x)S2 (0<=x<=1) by using measurement techniques of X-ray diffraction, polarized thermoreflectance (PTR), and X-ray photoelectron spectroscopy (XPS). Single crystals of Cu(AlxIn1-x)S2 (0<=x<=1) (0 and E ^ polarizations. The PTR spectra clearly showed that the energy value of D increases with the increase of Al content x in the Cu(AlxIn1-x)S2 (0<=x<=1) series due to the enhanced strain in the lattice. The composition-dependent crystal-field-splitting energies can be evaluated and determined to be D(x)= (10±2)+( 139±5)×x meV. Based on the experimental analyses, the crystal structure and valence-band structure of the Cu(AlxIn1-x)S2 (0<=x<=1) (0<=x<=1) series are thus realized.
Composition Dependent Band Gaps of Single Crystal Cu2ZnSn(SxSe1-x)4 Solid Solutions
Authors: Wang Yi Ping , Levcenco Sergiu , Dumcenco Dumitru O. , Huang Ying Sheng , Ho Ching Hwa , Tiong Kwong Kau
Published: November 2012

Single crystals of Cu2ZnSn(SxSe1-x)4 (CZTSSe) solid solutions have deen grown by chemical vapor transport technique using ICl3 as a transport agent. Analyzing the X-ray diffraction patterns reveal that the as-grown CZTSSe solid solutions are crystallized in kesterite structure and the lattice parameters are determined. The S contents of the obtained crystals are estimated by Vegard’s law. The composition dependent band gaps of CZTSSe solid solutions are studied by electrolyte electroreflectance (EER) techniques. The band gaps of CZTSSe are evaluated by a lineshape fit of the EER spectra and are found to increase almost linearly with the increase of S content.
Experimental Reinvestigation of Ni-Zr System
Authors: Kosorukova Tetiana , Ivanchenko Volodymir , Firstov Georgiy , Noël Henri
Published: November 2012

Phase equilibria in the Ni-Zr system were experimentally reinvestigated by means of differential thermal, electron microprobe, X-Ray diffraction and metallographic analyses of the alloys, which were prepared by arc melting and then annealed at 900°C during 2 weeks. The temperatures of equilibria reactions in Ni-Zr systems were specified and phase diagram Ni-Zr was reconstructed.
Thermoelectric Properties of Pb1-xCdxSe Crystals Grown by Vertical Bridgman Method
Authors: Gau Horng Jyh , Chiou Yih Jye , Wu Ching Cherng , Kuo Yung Kang , Ho Ching Hwa
Published: November 2012

Single crystals of Pb1-xCdxSe compounds with x = 0, 0.01, 0.03, 0.05, 0.07 and 0.1 were grown by vertical Bridgman method. The crystalline phase and stochiometry for these crystals were investigated by X-ray diffraction, SEM and electron-probe microanalysis (EPMA). The thermoelectric behaviors for the Pb1-xCdxSe crystals were studied by means of thermal and carrier transport measurements in the temperature range between 50K and 400K. X-ray diffraction and SEM analysis confirmed that as-grown Pb1-xCdxSe crystals are simgle phase. The experimental results showed that the PbTe sample is p-type semiconductor but Pb1-xCdxSe samples with x = 0.01, 0.03, 0.05, 0.07 and 0.1 are n-type semiconductors. Temperature dependences of resistivity, Seebeck coefficient, and thermal conductivity for the various compositions of Pb1-xCdxSe were analyzed. The dimensionless thermoelectric figure of merit ZT for these compounds was evaluated and discussed. It was found that Pb0.95Cd0.05Se exhibits the best thermoelectric performance. The maximum figure of merit (ZT) of Pb0.95Cd0.05Se is about 0.47 at 290 K.
The Studies of Ac Magnetic Susceptibility and Higher Harmonics in Cd0.88Cr1.96V0.31Se4 Semiconductor
Authors: Groń Tadeusz , Malicka Ewa , Pacyna Andrzej W. , Zawisza Beata
Published: November 2012

The complex ac dynamic magnetic susceptibility was used to study the magnetic state in the polycrystalline Cd0.88Cr1.96V0.31Se4 spinel. The temperature dependences of the zero field in-phase (real part) and out-of-phase (imaginary part) components of fundamental susceptibility showed the mictomagnetic behavior at low temperature and a weak Hopkinson-like effect close to the ordering temperature. These effects are also evidenced by the non-vanishing both the real and imaginary components of the 2nd and 3rd harmonics in the region of magnetic order.
High-Temperature Optical Characterization of Transition Metal Dichalcogenides by Piezoreflectance Measurements
Authors: Dumcenco Dumitru O. , Huang Ying Sheng , Tiong Kwong Kau , Colev Andrei , Gherman Corneliu , Kulyuk Leonid
Published: November 2012

A systematic optical characterization of transition metal dichalcogenide layered crystals grown by chemical vapour transport method as well as of natural molybdenite were carried out by using piezoreflectance (PzR) measurements. From a detailed lineshape fit of the room-temperature PzR spectra over an energy range from 1.6 to 5.0 eV, the energies of the band-edge excitonic and higher lying interband direct transitions were determined accurately. The possible assignments of the different origins of excitonic transitions are discussed. The near direct band edge A and B excitonic transitions detected in PzR spectra show a linear red-shift with the temperature increasing up to 525 K. The values of temperature-dependent energies of the excitonic transitions A and B are evaluated and discussed.
Thermodynamic Investigations of Chalcogenide Glasses from the GeSe2–Sb2Te3–CdTe System
Authors: Aljihmani Lilia , Vassilev Venceslav , Hristova-Vasileva Temenuga
Published: November 2012

Glassy samples from the GeSe2-Sb2Te3-CdTe system are synthesized. The thermal characteristics (glass-transition Tg, crystallization Tcr and melting Tm temperatures) are determined using differential thermal analysis. On the base of the values of these temperatures the glass forming ability of the glasses is determined by the Hruby’s criterion. The main thermodynamic parameters (enthalpy ΔH and entropy ΔS alternation) of the crystallization are calculated. The values of the ΔH and ΔS vary within 21.196 – 98.625 kJ/mol and 33.91 – 170.93 J/(mol.K), respectively. The influence of the composition on the investigated characteristics is analysed.
Pd-Based Metallic Glass Films Formed by Electrodeposition Process
Authors: Mochizuki Chihiro , Senga Takashi , Shibata Masami
Published: November 2012

The formation of Pd-Ni-P and Pd-Ni-Cu-P metallic glass films using the electrodeposition method was examined. In this study, the structure and composition of these metallic alloys were investigated at various condition of electrodeposition. The X-ray diffraction pattern on the electrodeposited Pd-Ni-P films in the range of 18-69 at% Pd, 12-62 at% Ni and 9-21 at% P showed a broad diffraction peak, which indicates metallic amorphous structure. A result of DSC showed that the electrodeposited Pd-Ni-P films in the range of 36-57 at% Pd, 24-47 at% Ni and 16-21 at% P were metallic glasses. In addition, it was proven that the electrodeposited Pd54Cu8Ni22P16 film was metallic glass.
Mechanically Driven Dissolution of Sn in Near-Equiatomic Bcc FeCo
Authors: Loureiro J.M. , Costa Benilde F.O. , Le Caër Gerard , Malaman Bernard
Published: November 2012

Ternary alloys, (Fe50−x/2Co50−x/2)Snx (x ≤ 33 at.%), are prepared by mechanical alloying from powder mixtures of the three elements. As-milled alloys are studied by X-ray diffraction and 57Fe and 119Sn Mössbauer spectroscopy. The solubility of Sn in near-equiatomic bcc FeCo is increased from ~0.5 at. % at equilibrium to ~20 at.% in the used milling conditions. The average 119Sn hyperfine magnetic field at room temperature is larger, for any x, than the corresponding fields in mechanically alloyed Fe-Sn solid solutions.
Si Nanocrystals Deposited by HFCVD
Authors: Luna-López José Alberto , Garcia-Salgado G. , Carrillo-López J. , Vázquez-Valerdi Dianeli E. , Ponce-Pedraza A. , Díaz-Becerril T. , Flores Gracia F.J. , Morales-Sánchez A.
Published: November 2012

The structural and optical properties of Si nanocrystal (Si-nc) embedded in a matrix of off-stoichiometric silicon oxide (SiOx, x<2) films prepared by hot filament chemical vapor deposition technique were studied. The films emit a wide photoluminescent spectra and the maximum peak emission shows a blue-shift as the substrate temperature (Ts) decreases. Also, a wavelength-shift of the absorption edge in transmittance spectra is observed, indicating an increase in the energy band gap. The Si-nc’s size decreased from 6.5 to 2.5 nm as Ts was reduced from 1150 to 900 °C, as measured through High Resolution Transmission Electron Microscopy analysis. A combination of mechanisms is proposed to explain the photoluminescence in the SiOx films, which involve SiOx defects and quantum confinement effects.
Isothermal Sections of the U-Fe-Sb Ternary System
Authors: Henriques Margarida S. , Malnoe Thomas , Tougait Olivier , Vilar Rui , Gonçalves Antonio Pereira
Published: November 2012

A systematic study on the ternary uranium-iron-antimony was made at 700 and 750°C through powder X-ray diffraction and Scanning Electron Microscopy coupled with Energy Dispersive Spectrometry. The assessed sections confirmed the existence and crystal structure of the binary intermetallic compounds as well as the ternary phase UFeSb2. Moreover it was found that UFeSb2 is part of a solid solution, UFe1-xSb2, stable for 193Fe3-xSb4, crystallizing in the cubic type Y3Au3Sb4 and stable for 22
Soft Chemistry Synthesis of Complex Oxides Using Protonic Form of Titanates HLnTiO4 (Ln=La, Nd)
Authors: Abdulaeva Liliya , Silyukov Oleg , Zvereva Irina , Petrov Yu.
Published: November 2012

In the present work protonic forms of layered n=1 Ruddlesden-Popper oxides HLnTiO4 (Ln=La, Nd) were used as starting point for synthesis of three series of the perovskite-like compounds. Characterization by SEM, powder XRD and TGA has been performed for the determination of the structure and composition of synthesized oxides.
Two-Stage Hydrogen Compression Using Zr-Based Metal Hydrides
Authors: Koultoukis Evangelos D. , Makridis Sofoklis S. , Fruchart Daniel , Stubos Athanasios K.
Published: November 2012

Zr-based AB2-Laves phase type alloys containing the same type of A and B metals, have been prepared from pure elements by melting and subsequent re-melting under argon atmosphere by using a HF-induction levitation furnace. Characterization of the alloys has resulted from powder X-Ray Diffraction (XRD) measurements and SEM/EDX analyses. Systematic PCI (Pressure-Composition-Isotherms) measurements have been recorded at 20 and 90 °C, using a high-pressure Sievert's type apparatus. The purpose of this study is to find a series of alloys promptly forming metal hydrides (MH) with suitable properties in order to build a MH-based hydrogen compressor, working in the same way between 20 and ~100 °C.
ZnO Nanostructured Thin Films Applied on Ibuprofen Photoelectrodegradation
Authors: Frade Tânia , Gomes Anabela
Published: November 2012

ZnO nanorods were prepared on fluorine doped tin oxide (FTO) using the electrodeposition method. The architecture of the ZnO nanorods was strongly modified by changing the applied potential and bath composition. Scanning electron microscopy (SEM) confirmed the successful formation of ZnO nanorods and the diameter increasing due to the increase of deposition potential and nitrate zinc concentration. The annealed ZnO electrodes demonstrated a good performance on the Ibuprofen degradation. Percentage values of Ibu degradation varying between 22 and 30 % for 3 h period were obtained.
An Experimental Investigation of the U-Mo-C Ternary Diagram
Authors: Peniel Matthieu , El Bekkachi Houda , Tougait Olivier , Pasturel Mathieu , Noël Henri
Published: November 2012

The isothermal sections of the U-Mo-C ternary system have been established at 1000°C and 1400°C, using powder X-ray diffraction, scanning electron microscopy coupled with energy dispersive X-ray analysis for the quantification of U and Mo and differential thermal analysis. The main differences between the two sections are the appearance of liquid phase at about 1230°C, due to the peritectic decomposition of γ-UMo, and the peritectoid decompositions of MoC and β’’ Mo2C. No other transformation was detected in this temperature range, especially one involving the two only ternary phases found, UMoC2 and U2Mo2C3.
Effect of Vacancies on Positron Annihilation and Hyperfine Interactions in Fe-Al Alloys - Ab Initio Study
Authors: Deniszczyk Józef , Boroński Edward , Hanc Aneta
Published: November 2012

Vacancies occupying different sub-lattices of D03 structure of Fe3Al alloy were investigated by the full potential linearized augmented plane wave method. The calculations basing on the super-cell approach have been performed for the vacancy concentrations of 1.6 and 3 at.%. For both concentrations the sub-lattice preference for vacancy location was determined. The dependence of vacancy formation energy on magnetic state of structure has been found. The positron lifetimes for the annihilation in the bulk (Fe3Al) and in vacancies have been investigated basing on the ab initio results for the electron density. The effect of vacancies on spin magnetic moment and hy-perfine parameters of Fe atoms neighboring the vacancy was examined. The results are discussed and compared with the data available.
Electronic Structure of Mineral Libethenite Series: A Minimal Model Approach
Authors: Karmakar Debjani , Yakhmi J.V.
Published: November 2012

In mineral Libethenite series, A2PO4OH [A = Co, Cu], onset of low-dimensional magnetic behavior from a three-dimensional long-range ordered system under substitution of Cu in place of Co is investigated with the help of first principles multistep approaches. Detailed structural analysis of the relaxed system, while combined with orbital characterization of localized 3d-bandstructure, enables a thorough understanding of the evolution of magneto-structural correlation along the series. Determination of relevant exchange paths and subsequent estimation of exchange integrals along those paths provide the required information to construct a minimal model spin-Hamiltonian for the low-dimensional system, solution of which under first-order perturbation theory leads to approximate evaluation of spin-gap present in this system. Obtained results can explain all the experimental observations present in the literature.
Magnetism and Structural Behavior of CeRuSn Single Crystal
Authors: Fikáček Jan , Prchal Jiří , Prokleška Jan , Císařová Ivana , Sechovský Vladimír
Published: November 2012

We have synthesized CeRuSn single crystals and performed measurements of electrical resistivity and specific heat. At high temperatures, abrupt transitions were observed at 290 and 225 K in electrical resistivity during cooling. Both transitions are connected with a large temperature hysteresis. Low temperature properties are dominated by an antiferromagnetic transition at 2.9 K, which involves only half of cerium ions, leaving the rest of them non-magnetic. A significant magnetocrystalline anizotropy was revealed by application of external magnetic field.
Magnetic Properties of Tb2Pd2In; Single Crystal Study
Authors: Maskova Silvie , Kolomiets Aleksandre V. , Havela Ladislav , Andreev Alexander V. , Svoboda Pavel , Skourski Yurii
Published: November 2012

A pilot polycrystalline magnetization study of Tb2Pd2In in comparison with new single-crystal data reveal interesting magnetocrystalline anisotropy with field induced spin-flip transitions both in the c- and a-axis of the tetragonal structure.
Numerical Analysis of Time Dependent Effects in Bulk Nanocrystalline Hard Magnets
Authors: Ziółkowski Grzegorz , Chrobak Artur , Randrianantoandro Nirina , Chełkowska Grażyna
Published: November 2012

The presented work concerns numerical analysis of t-dependent magnetization curves. We propose the approach consisting in application of the so-called simulated annealing algorithm (SA) supplemented with local maximum entropy condition. Efficiency of the SA procedure and its parameters was tested with the use of computer generated curves derived from known distributions of relaxation time τ. Based on the determined SA parameters the analysis of empirical M(t) dependences measured for (Fe80Nb6B14)1-xTbx (x=0.08, 0.16) bulk nanocrystalline alloys were also carried out. As it was shown the SA procedure allows determining distributions of relaxation time without preliminary assumption about its shape and number of components.
Neutron Diffraction Study of the Hexagonal Perovskite-Type Compound LaCrGe3
Authors: Cadogan J.M. , Lemoine Pierric , Slater Brianna R. , Mar Arthur , Avdeev Maxim
Published: November 2012

The BaNiO3-type structure and the ferromagnetic order (TC = 78 K) of the Cr sublattice in LaCrGe3 have been confirmed by neutron powder diffraction measurements. At 20 K, the magnetic structure is collinear along the c axis with a Cr magnetic moment of 1.24(4) μB. Below 3 K, LaCrGe3 has a spin-canted ferromagnetic structure with a canting angle θ of 32(6) and a Cr magnetic moment of 1.31(4) μB at 1.7 K.
Evolution of the Magnetic and Electrical Properties in the Ce-Co-Ge System
Authors: Pasturel Mathieu , Pikul Adam , Wisniewski Piotr , El Bekkachi Houda , Soudé Arnaud , Tougait Olivier , Noël Henri
Published: November 2012

Among the 10 phases reported to exist at 973 K in the Ce-Co-Ge ternary system, a strong dependence of the magnetic and transport properties on the constituent concentration has been evidenced. Close to the Ce-Ge binary axis, the ternary phases exhibit ferromagnetic-like ordering with low TC, while increasing the cobalt concentration leads first to a paramagnetic area, then to an antiferromagnetic one and finally to ferromagnetism with high TC for cobalt and Co-rich binaries. Similarly, electrical resistivity and thermopower measurements evidence a rather metallic behavior for cerium poor phases while an increase in the Ce-content results in an increase of the Kondo-like interactions.
Quantum Oscillations in Ultra Pure PtSn4
Authors: Inamdar Manjusha , Kriegisch Martin , Shafeek Lubuna , Sidorenko A. , Müller Herbert , Prokofiev Andrey , Blaha Peter , Paschen Silke
Published: November 2012

PtSn4 is a non-congruently melting compound in the Pt-Sn binary phase diagram, crystallizing in the centrosymmetric space group Ccca. We report on single crystal growth, temperature dependent electrical resistivity, isothermal field-dependent magnetization and magnetostriction, and on band structure calculations of this transition metal compound. The high quality of the sample makes it possible to observe clearly resolved quantum oscillations in the magnetization data for temperatures as high as 20 K and in magnetic fields as low as 10 kOe. We found several frequencies along the three crystallographic directions and could relate them to several extremal orbits on the Fermi surface.
Magnetic Properties of MM’X (M= Mn, M’= 3d or 4d Metal, X = P, As, Si, Ge) Compounds with Hexagonal or Orthorhombic Crystal Structure
Authors: Zach Ryszard , Toboła Janusz , Chajec Wieslaw , Fruchart Daniel , Ono Fumihisa
Published: November 2012

Abstract. In this review paper comparison of magnetic properties in several MM’X-type intermetallics is presented. It may be summarized that main role in variation of magnetic interactions is played by modification of metallic sublattice in the tetrahedral but not in the pyramidal sites. It was shown not only in the case of composition, temperature and magnetic field dependencies but also by pressure variation of magnetic interactions. The latter was confirmed especially by electronic band structure calculations. Finally, in this report spin component and orbital one of magnetic moments for CoMnGe is presented for the first time.
The Interrelationship between Dentistry and Physiotherapy in the Treatment of Temporomandibular Disorders
Authors: de Toledo Evane Gonçalves , Silva Daniel Piccinini , de Toledo Juliane Alvarez , Salgado Ivone Oliveira
Published: November 2012

Aim

This study aimed to compare the effectiveness of interdisciplinary work between dentistry and physiotherapy as well as to determine the temporomandibular disorders (TMD) patients’ treatment plan.

Materials and methods

The sample consisted of 300 patient records from the ATM service (Faculty of Dentistry, Federal University of Juiz de Fora) file. Three factors were analyzed: (1) Therapy, which were transcribed physical therapy modalities used; 2) If there were any guidelines or procedures for home exercises without the professionals presence; 3) the temporomandibular joint (TMJ) palpation pain rates, transferred to a pain level measurements table according to visual analog scale (VAS). The Chi-square test was applied for statistical analysis with a significance level p ≤ 0.05.

Results

All physiotherapy modalities used separately or mixed contributed to TMJ pain relief. Guidelines for physical therapy at home proved to be very useful to pain decreasing.

Conclusion

It was concluded that the effectiveness of an interdisciplinary work in dentistry and physiotherapy treatments for TMD has been properly verified. It is essential to have an interdisciplinary treatment plan, where the physical therapy helps the pain relief and dentistry treats the disorders related to the stomatognathic system.

Clinical significance

The interdisciplinary work between dentistry and physiotherapy is more effective in TMD treatment.

How to cite this article

de Toledo EG Jr, Silva DP, de Toledo JA, Salgado IO. The Interrelationship between Dentistry and Physiotherapy in the Treatment of Temporomandibular Disorders. J Contemp Dent Pract 2012;13(5):579-583.
Nature of Occlusion during Eccentric Mandibular Movements in Young Adults
Authors: Sreekumar AV , Rupesh PL , Pradeep Nishna
Published: November 2012

Aim

The aim of this study was to find out the nature of occlusion and tooth contact during various eccentric mandibular movements in young adults with class I occlusion.

Materials and methods

The sample consisted of 100 young adults with class I occlusion with full complement of teeth.

Anterior disclusion in centric occlusion was demonstrated using a shim stock interposed between the upper and lower anteriors. Disclusion of posteriors was ascertained during 1.5 mm straight protusion and in edge-to-edge protrusion, visually as well as using a silk floss method. Posterior disclusion was also verified during lateroprotrusion and crossover. Besides these occlusal wear of teeth also were observed.

Results

The results of this study showed that the anterior disclusion is seen only in one-fourth of the subjects compared to almost three-fourth showing posterior disclusion. Mutually protected occlusion was also seen only in one-fourth of the subjects. Canine protective mechanism is seen in a relatively large number of subjects, but it was not overwhelmingly predominant. No correlation could be established between cuspid wear and the type of occlusion. A relatively high percentage of subjects showed wear on posterior teeth when there was no posterior disclusion.

Conclusion

From the above study it is seen that posterior disclusion is acknowledged as a common factor except when a bilateral balance is present. Since bilateral balance is harmful, the ideal occlusal relationship in eccentric movements is in favor of posterior disclusion. Posterior disclusion is easily obtainable when restorations are planned.

Clinical significance

From the findings and results it has been possible to make some contributions on the nature of tooth contacts and disclusion during various eccentric movements and compare it with the requirements of ideal occlusion.

How to cite this article

Sreekumar AV, Rupesh PL, Pradeep N. Nature of Occlusion during Eccentric Mandibular Movements in Young Adults. J Contemp Dent Pract 2012;13(5):612-617.
Estimation of Salivary Nitric Oxide in Recurrent Aphthous Ulcer and Oral Lichen Planus Patients with Its Clinical Significance
Authors: Baad RK , Jagtap Kiran
Published: November 2012

Aim

The present study was undertaken to study the role of nitric oxide in human saliva and its diagnostic/prognostic role in recurrent aphthous ulcers (RAU) and oral lichen planus (OLP).

Materials and methods

The study was carried out at outpatient department of Govt Dental College and Hospital, Aurangabad. Twenty cases with RAU, 15 with OLP and 30 healthy individuals were included in the study. The clinically diagnosed known cases of RAU and OLP were included after taking the detail case history and subjected to blood analysis for hemogram and biochemically salivary nitric oxide was estimated.

Results

The salivary nitric oxide levels were found to be increased significantly in RAU and OLP group, when compared with controls. Further, significantly increased levels have been observed in OLP group, when compared with RAU group (p < 0.001). The salivary nitric oxide levels were found to be increased significantly in minor RAU than major RAU and increased in erosive type of OLP than nonerosive type of OLP.

Conclusion

Thus, salivary nitric oxide can be treated as a diagnostic tool for the differential diagnosis of RAU and OLP.

Clinical significance

Nitric oxide plays an important role in modifying physiopathological processes of oral mucosal membrane so has diagnostic as well as prognostic value.

How to cite this article

Jagtap K, Baad RK. Estimation of Salivary Nitric Oxide in Recurrent Aphthous Ulcer and Oral Lichen Planus Patients with Its Clinical Significance. J Contemp Dent Pract 2012;13(5):623-626.
A Study to evaluate and compare the Efficacy of Preprocedural Mouthrinsing and High Volume Evacuator Attachment Alone and in Combination in Reducing the Amount of Viable Aerosols Produced during Ultrasonic Scaling Procedure
Authors: Malagi Sachin , Devker Nihal , Mohitey Jyoti , Vibhute Akshay , Chouhan Vivek Singh , Chavan Prithviraj , Joseph Rosemary
Published: November 2012

Background and objectives

In recent years, ultrasonics has gained prime importance and is considered a valuable tool in the dentist's armamentarium. Studies have confirmed that an aerosolized bacterial contamination is produced during the use of ultrasonic scalers.

Aim

To evaluate and compare the efficacy of preprocedural mouthrinsing using a bis-biguanide (chlorhexidine gluconate 0.2%) and high volume evacuator attachment alone and in combination in reducing the amount of viable aerosols produced during ultrasonic scaling procedure.

Materials and methods

A total 90 subjects were assigned to group I (who rinsed with 0.2% chlorhexidine gluconate prior to scaling), group II (high volume evacuator attachment was used during ultrasonic scaling) and group III (who rinsed with 0.2% chlorhexidine gluconate prior to scaling and in whom high volume evacuator attachment was used during ultrasonic scaling). Control group consisted of subject's whose mouth was scaled using a piezoelectric ultrasonic scaler without preprocedural rinsing or high volume suction.

Aerosol samples were collected using blood agar plates. The blood agar plates containing the aerosol sample were taken to the microbiology department as soon as the sampling was over and were subjected to aerobic culturing.

Results

The values obtained showed that all the three groups were effective in reducing the mean colony forming units (CFUs).

Conclusion

The results of this study showed that preprocedural rinse and high volume suction were effective when used alone as well as together in reducing the microbial load of the aerosols produced during ultrasonic scaling. There was a significant reduction in the number of CFUs in aerosol samples obtained.

How to cite this article

Devker N, Mohitey J, Vibhute A, Chouhan VS, Chavan P, Malagi S, Joseph R. A Study to evaluate and compare the Efficacy of Preprocedural Mouthrinsing and High Volume Evacuator Attachment Alone and in Combination in Reducing the Amount of Viable Aerosols Produced during Ultrasonic Scaling Procedure. J Contemp Dent Pract 2012;13(5): 681-689.
Efficacy of Microwaves and Chlorhexidine for Disinfection of Pacifiers and Toothbrushes: An in vitro Study
Authors: Bhat Chetan , Chamele Jay , Saraf Tanvi , Jadhav Abhijeet , Beg Aumir , Ubeja Ritu , Patil Padmeshwari
Published: November 2012

Purpose

The purpose of this study was to evaluate, in vitro, the contamination of toothbrushes and pacifiers by Streptococcus mutans, and the efficacy of microwave and chlorhexidine for their disinfection.

Materials and methods

Sixty pacifiers and 60 toothbrushes were contaminated with S. mutans and then divided into groups according to the disinfection protocol: Group 1—chlorhexidine solution; group 2—microwave sterilization; and group 3—sterile tap water. The devices were evaluated microbiologically after disinfection for the survival of S. mutans colonies and were examined. The results were analyzed statistically by ANOVA and Turkey test.

Results

The results of both types of evaluation showed a large number of S. mutans colonies after spraying with sterile tap water, and chlorhexidine spraying and microwaving were effective in eliminating colonies. Groups 1 and 2 were statistically similar to each other (p > 0.05) and differed significantly from group 3 (p < 0.05).

Conclusion

The 0.12% chlorhexidine solution spray and 7 minutes of microwave irradiation were almost equally effective for disinfection of pacifiers and toothbrushes.

How to cite this article

Chamele J, Bhat C, Saraf T, Jadhav A, Beg A, Jagtap C, Ubeja R, Patil P. Efficacy of Microwaves and Chlorhexidine for Disinfection of Pacifiers and Toothbrushes: An in vitro Study. J Contemp Dent Pract 2012;13(5):690-694.
Accidental Aspiration of Dental Crowns and Retrieval
Authors: Singh Sukhdeep , Singh Gurminder , Gambhir Ramandeep Singh
Published: November 2012

Aim

The aim of this article is to create awareness among the dental practitioners regarding the various accidents which can happen during a dental procedure and stress upon the preventive measures that can be taken to reduce the same.

Background

This article presents a case of aspiration of dental crowns by the patient and its retrieval by coughing and preventive measures which can be taken to avoid such circumstances.

Case description

A patient reporting to private dental practice accidentally aspirated the two-unit prosthesis (crowns) in the right lung during cementation. He was immediately taken to the hospital, where chest radiographs and computed tomographic (CT) scan were done in order to locate the actual position of the prosthesis. Bronchoscopy was planned to retrieve the crowns but the patient had a bout of cough and the crowns came out. A chest radiograph was taken to confirm the absence of crowns.

Clinical significance

Taking adequate precautions while performing any dental procedure in supine position can decrease the occurrence of such incidents. Rigid bronchoscopy is the advised method of retrieval in case the crowns are not coughed out.

How to cite this article

Singh G, Gambhir RS, Singh S, Kaur H. Accidental Aspiration of Dental Crowns and Retrieval. J Contemp Dent Pract 2012;13(5):716-718.
Contrasting patterns of climatic changes during the Holocene in the Central Mediterranean (Italy) reconstructed from pollen data
Authors: Peyron O. , Magny M. , Goring S. , Joannin S. , de Beaulieu J.-L. , Brugiapaglia E. , Sadori L. , Garfi G. , Kouli K. , Ioakim C. , Combourieu-Nebout N.
Published: November 2012

Abstract. Lake-level records from Italy suggest a north–south climatic partition in the Central Mediterranean during the Holocene with respect to precipitation, but the scarcity of reliable palaeoclimatic records in the North and Central-Southern Mediterranean means new evidence is needed to validate this hypothesis. Here, we provide robust quantitative estimates of Holocene climate in the Mediterranean region based on four high-resolution pollen records from Northern (Lakes Ledro and Accesa) and Southern (Lakes Trifoglietti and Pergusa) Italy. Multiple methods are used to provide an improved assessment of the paleoclimatic reconstruction uncertainty. The multi-method approach uses the pollen-based Weighted Averaging, Weighted-Average-Partial-Least-Squares regression, Modern Analogues Technique, and the Non-Metric-Multidimensional Scaling/Generalized-Additive-Model methods. The precipitation seasonality reconstructions are validated by independent lake-level data, obtained from the same records. A climatic partition between the north and the south during the Holocene confirms the hypothesis of opposing mid-Holocene summer precipitation regimes in the Mediterranean. During the early-to-mid-Holocene the northern sites (Ledro, Accesa) are characterized by minima for summer precipitation and lake-levels while the southern sites (Trifoglietti, Pergusa) are marked by maxima for precipitation and lake-levels. During the late Holocene, both pollen-inferred precipitation and lake-levels indicate the opposite pattern, a maximum in North Italy and a minimum in Southern Italy/Sicily. Summer temperatures also show partitioning, with warm conditions in Northern Italy and cool conditions in Sicily during the early/mid-Holocene, and a reversal during the Late-Holocene. Comparison with marine cores from the Aegean Sea suggests that climate trends and gradients observed in Italy shows strong similarities with those recognized from the Aegean Sea, and more generally speaking in the Eastern Mediterranean.
Temperature and precipitation signal in two Alpine ice cores over the period 1961–2001
Authors: Mariani I. , Eichler A. , Brönnimann S. , Auchmann R. , Jenk T. M. , Leuenberger M. C. , Schwikowski M.
Published: November 2012

Abstract. Water stable isotope ratios and net snow accumulation in ice cores are usually interpreted as temperature and precipitation proxies. However, only in a few cases a direct calibration with instrumental data has been attempted. In this study we took advantage of the dense network of observations in the European Alpine region to rigorously test the relationship of the proxy data from two highly-resolved ice cores with local temperature and precipitation, respectively, on an annual basis. We focused on the time period 1961–2001 with the highest amount and quality of meteorological data and the minimal uncertainty in ice core dating (±1 yr). The two ice cores come from Fiescherhorn glacier (Northern Alps, 3900 m a.s.l.) and Grenzgletscher (Southern Alps, 4200 m a.s.l.). Due to the orographic barrier, the two flanks of the Alpine chain are affected by distinct patterns of precipitation. Therefore, the different location of the two ice cores offers the unique opportunity to test whether the precipitation proxy reflects this very local condition. We obtained a significant spatial correlation between annual δ18O and regional temperature at Fiescherhorn. Due to the pronounced intraseasonal to interannual variability of precipitation at Grenzgletscher, significant results were only found when weighting the temperature with precipitation. For this site, disentangling the temperature from the precipitation signal was thus not possible. Significant spatial correlations between net accumulation and precipitation were found for both sites but required the record from the Fiescherhorn glacier to be shifted by −1 yr (within the dating uncertainty). The study underlines that even for well-resolved ice core records, interpretation of proxies on an annual or even sub-annual basis remains critical. This is due to both, dating issues and the fact that the signal preservation intrinsically depends on precipitation.
Seismic monitoring of precursory fracture signals from a destructive rockfall in the Vorarlberg Alps, Austria
Authors: Walter M. , Schwaderer U. , Joswig M.
Published: November 2012

Abstract. In this study we describe the seismic analysis of precursory patterns of a rockfall in the "Rappenlochschlucht", a gorge located in the Vorarlberg Alps, Austria. The rockfall with an estimated volume of 15 000 m3 occurred on 10 May 2011 (10:48:43 UTC) and destroyed a massive bridge construction. Fortunately, the rockfall did not cause any casualties. A permanent seismic network consisting of three seismic small arrays was installed in July 2009 in 5 km distance to the gorge, at the Heumoes slope, in order to detect and locate slope-related fracture processes within a radius of a few hundred meters. By chance, the rockfall with an estimated equivalent local magnitude of ML,eq = 2.3 was recorded by the seismic network. We observed several smaller rockfall events up to three hours, and 12 fracture signals up to five hours prior to the rockfall. The smaller rockfalls and the fractures were both located in the vicinity of the source area where the main event emerged, applying absolute and relative localization methods. These specific types of fracture signals located near by the gorge "Rappenlochschlucht" have never been observed in almost two years of permanent seismic monitoring. We interpret these fractures with magnitudes between ML = 0.4 and −0.5 as precursory signals of the main rockfall event. The observed fractures and the weaker rockfalls are sequences of initial stress relief within the rock mass and mass transferring processes, respectively, finally causing the destructive main rockfall event. To investigate possible triggers of the destructive rockfall event, several meteorological and hydrological data as well as the local seismicity during that period of time were analyzed and discussed in detail in this study. Unfortunately, no triggering factor of the rockfall event was identified, and remains therefore unknown.
Towards dynamics in flood risk assessment
Authors: Mazzorana B. , Levaggi L. , Keiler M. , Fuchs S.
Published: November 2012

Abstract. As a consequence of flood impacts, communities inhabiting mountain areas are increasingly affected by considerable damage to infrastructure and property. The design of effective flood risk mitigation strategies and their subsequent implementation is crucial for a sustainable development in mountain areas. The assessment of the dynamic evolution of flood risk is the pillar of any subsequent planning process that is targeted at a reduction of the expected adverse consequences of the hazard impact. Given these premises, firstly, a comprehensive method to derive flood hazard process scenarios for well-defined areas at risk is presented. Secondly, conceptualisations of a static and dynamic flood risk assessment are provided. These are based on formal schemes to compute the risk mitigation performance of devised mitigation strategies within the framework of economic cost-benefit analysis. In this context, techniques suitable to quantify the expected losses induced by the identified flood impacts are provided.
Cementation of Bioproducts Generated from Biodegradation of Radioactive Cellulosic-Based Waste Simulates by Mushroom
Authors: Eskander S. B. , Abd El-Aziz S. M. , El-Sayaad H. , Saleh H. M.
Published: November 2012

The current work was devoted to study the solidification of bioproducts originated from the bioremediation of mixture of solid cellulose-based radioactive waste simulates using a mushroom (Pleurotus pulmonarius), in Portland cement. The obtained solidified waste form was subjected to mechanical integrity qualification after curing periods of 28 and 90 days. Chemical performance of the cement-waste form was also evaluated in different leachant media during 540 days. The results obtained gave useful information about the mechanical, physical, and chemical performances of the final cement-waste form incorporated the radioactive bioproducts. Moreover, it indicated that cement can provide a highly durable form that ensures a long-term stability of the solidified waste material and can act as a first barrier against the release of radiocontaminants from radioactive wastes to the surrounding environment.
Influence of breed, milk diet and slaughter weight on carcass traits of suckling kids from seven Spanish breeds
Authors: Panea B. , Ripoll G. , Horcada A. , Sañudo C. , Teixeira A. , Alcalde M. J.
Published: November 2012

This experiment aimed to describe the influence of production system on the following characteristics from seven Spanish goat breeds: carcass weight, dressing percentage, head weight, viscera weight, kidney fat weight, fatness score, carcass length, leg length, rump perimeter, rump width, kidney fat colour and tissue composition of shoulder. Experiment involved 201 male, single-birth suckling kids from five meat and two dairy breeds. Animals from meat breeds were slaughtered at two targets carcass weights (light, 4 kg; heavy, 7 kg). In dairy breeds, half of the animals were reared with dam’s milk and the other half with a milk replacer and all of them were slaughtered at light weight (4 kg). Statistics consisted in two GLM, means for each variable, a PCA to study relationships between variables and a discriminant analysis to compare breeds. In dairy breeds, breed had greater influence than milk diet, with breed effect being particularly strong for kids that were fed with natural milk. In meat breeds, slaughter weight was more important than breed and many significant interactions were found between both effects. All carcass traits were closely related to each other and to slaughter weight. Slaughter weight was also positively related to dressing percentage and to fatness degree. Discriminant analysis explained 76.1% of variability and separated dairy breeds, with well-fattened, medium-shaped carcasses, from meat breeds, with good conformations and medium fatness degrees. Hence, carcass traits were able to group breeds by diary or meat type.