Estimation of compensation ratio by identifying the presence of different hopping conduction mechanisms in SnO2 thin films

WOS: 000287543300044The electrical properties of undoped SnO2 thin films prepared by the sol-gel technique were investigated by conductivity measurements in a temperature range of 50-200 K. Structural characterizations of the films were performed by atomic force microscopy and X-ray diffraction. Optical properties of the samples were also characterized by optical absorption spectroscopy. The different hopping models were used to investigate the characteristics of electrical conduction by hopping in employed temperature range. It was shown that three types of behavior can be expected, nearest-neighbour hopping at high temperatures, the Mott variable-range hopping at low temperatures and Efros-Shklovskii variable-range hopping at lower temperatures. The criteria for the observation of these three regions were established and the transitional behavior of the conductivity was determined. The experimentally determined critical transition temperatures were at the orders of magnitudes with what could be expected based on hopping conduction calculations. Under these analyses, the compensation ratio of the films was determined. (C) 2010 Elsevier B.V. All rights reserved.State of Planning Organization of TurkeyTurkiye Cumhuriyeti Kalkinma Bakanligi [2001K120590]; Ankara University BAPAnkara University [2007-07-45-054]This work is supported by the State of Planning Organization of Turkey under Grant No. 2001K120590 and the Ankara University BAP under Project Number 2007-07-45-054. We would also like to thank Prof. Dr. Yusuf Kagan Kadioglu and Ms. Murat Yavuz for providing XRD and AFM measurements

Phonon Softening and Direct to Indirect Bandgap Crossover in Strained Single Layer MoSe2

Motivated by recent experimental observations of Tongay et al. [Tongay et al., Nano Letters, 12(11), 5576 (2012)] we show how the electronic properties and Raman characteristics of single layer MoSe2 are affected by elastic biaxial strain. We found that with increasing strain: (1) the E' and E" Raman peaks (E1g and E2g in bulk) exhibit significant red shifts (up to 30 cm-1), (2) the position of the A1' peak remains at 180 cm-1 (A1g in bulk) and does not change considerably with further strain, (3) the dispersion of low energy flexural phonons crosses over from quadratic to linear and (4) the electronic band structure undergoes a direct to indirect bandgap crossover under 3% biaxial tensile strain. Thus the application of strain appears to be a promising approach for a rapid and reversible tuning of the electronic, vibrational and optical properties of single layer MoSe2 and similar MX2 dichalcogenides.Comment: http://link.aps.org/doi/10.1103/PhysRevB.87.12541

THE RELATIONSHIP BETWEEN TRUST, TURNOVER INTENTIONS AND EMOTIONS: AN APPLICATION

Managerial leaders and directors are required to succeed the method of “sense” and “emotion” very well, to achieve organizational aims (Lee, 2002). Organizations need to manage all the emotions and feelings and concepts that affect persons health and performance (Gross, 1999). Business life dealing with this issue has increased in seriousness because, the effect of emotions in decision making cleared with academic studies. There is a need to find the path to the correct leadership of emotions. Emotions in the organization help to identify thoughts about the presence and desire to work (Jackson, 2006). The main purpose of this study, which should be considered a descriptive survey in the general sense, is to investigate the relationship between emotional expressions, trust and turnover intentions. Two different surveys were used in order to measure and assess the emotions expressions, trust and turnover intentions. The survey conducted on 200 employees of the public sector institution. Data, obtained from questionnaires analyzed through the SPSS statistical packaged software. We found that especially trust factors (Trust in management, co-worker trust and trust to manager) had a significant effect on “satisfaction” factor of turnover intentions. In addition, we found that “Co-worker trust” had a negative and significant effect on “Seek for job” factor of turnover intentions

Experimental application of sum rules for electron energy loss magnetic chiral dichroism

We present a derivation of the orbital and spin sum rules for magnetic circular dichroic spectra measured by electron energy loss spectroscopy in a transmission electron microscope. These sum rules are obtained from the differential cross section calculated for symmetric positions in the diffraction pattern. Orbital and spin magnetic moments are expressed explicitly in terms of experimental spectra and dynamical diffraction coefficients. We estimate the ratio of spin to orbital magnetic moments and discuss first experimental results for the Fe L_{2,3} edge.Comment: 11 pages, 2 figure

A novel index in healthy infants and children — subarachnoid space: ventricle ratio

Background: The subarachnoid space (SAS) and ventricular width (VW) in normalinfants and children were studied with ultrasonography to provide the objectivemeasurement and define a normal range for these measurements. The additional aim was to determine the stable ratio as a SAS/VW.Materials and methods: A total of 100 healthy subjects, including 48 males and52 females, were studied. The cases were divided into 3 age groups: 0–6 months(n = 65), 7–12 months (n = 24) and > 13 months (n = 11). Transfontanel ultrasonography was performed in all the cases. SAS, VW and the SAS/VW ratios were calculated. The study was approved by the ethical committee. All parents wereinformed about the sonographic examination and their approvals were taken.Results: SAS was calculated as 3.1 (0.5–6) mm and VW was calculated as 3.6(1.3–5) mm. SAS/VW ratio was 0.9 ± 0.3. There was no statistically significant difference among SAS, VW and SAS/VW ratios in 3–97 percentile group (p > 0.05).Conclusions: Ultrasonography can be used as a practicable and reproducible modalityin the measurement of SAS and VW in healthy children. It is a non-invasivemethod and allows for serial follow-up. SAS/VW ratio can be used as an index inhealthy children

Determination of the branching ratios Γ(KL→3π0)/Γ(KL→π+π−π0)\Gamma (K_L \to 3 \pi^0) / \Gamma (K_L \to \pi^+ \pi^- \pi^0) and Γ(KL→3π0)/Γ(KL→πeν)\Gamma (K_L \to 3 \pi^0) / \Gamma (K_L \to \pi e \nu )

Improved branching ratios were measured for the $K_L \to 3 \pi^0$ decay in a neutral beam at the CERN SPS with the NA31 detector: $\Gamma (K_L \to 3 \pi^0) / \Gamma (K_L \to \pi^+ \pi^- \pi^0) = 1.611 \pm 0.037$ and $\Gamma (K_L \to 3 \pi^0) / \Gamma (K_L \to \pi e \nu ) = 0.545 \pm 0.010$. From the first number an upper limit for $\Delta I =5/2$ and $\Delta I = 7/2$ transitions in neutral kaon decay is derived. Using older results for the Ke3/K$\mu$3 fraction, the 3$\pi^0$ branching ratio is found to be $\Gamma (K_L \to 3 \pi^0 )/ \Gamma_{tot} = (0.211 \pm 0.003)$, about a factor three more precise than from previous experiments

B(H) Constitutive Relations Near H_c1 in Disordered Superconductors

We provide a self-contained account of the B vs. H constitutive relation near H_c1 in Type II superconductors with various types of quenched random disorder. The traditional Abrikosov result B ~ [ln (H - H_c1)]^{-2}, valid in the absence of disorder and thermal fluctuations, changes significantly in the presence of disorder. Moreover, the constitutive relations will depend strongly on the type of disorder. In the presence of point disorder, B ~ (H - H_c1)^{3/2} in three-dimensional (thick) superconductors, as shown by Nattermann and Lipowsky. In two-dimensional (thin film) superconductors with point disorder, B ~ (H - H_c1). In the presence of parallel columnar disorder, we find that B ~ exp[-C / (H - H_c1)] in three dimensions, while B ~ exp[-K / (H - H_c1)^{1/2}] in two dimensions. In the presence of nearly isotropically splayed disorder, we find that B ~ (H - H_c1)^{3/2} in both two and three dimensions.Comment: 37 pages, 12 figures included in text; submitted to Physica

The Minimal Supersymmetric Standard Model: Group Summary Report

CONTENTS: 1. Synopsis, 2. The MSSM Spectrum, 3. The Physical Parameters, 4. Higgs Boson Production and Decays, 5. SUSY Particle Production and Decays, 6. Experimental Bounds on SUSY Particle Masses, 7. References.Comment: 121 pages, latex + epsfig, graphicx, axodraw, Report of the MSSM working group for the Workshop "GDR-Supersym\'etrie",France. Rep. PM/98-4

Experimental study of solubility of elemental sulphur in methane

International audienceThe chemical engineering department of LaTEP has been working for many years on theproblem of sulphur deposition especially in natural gas network [1, 2]. The solid sulphurappears immediately downstream of a pressure reduction facility. One of the hypothesesproposed to explain the solid formation, based on a thermodynamic approach, is thedesublimation of sulphur. During gas expansion, both pressure and temperature decrease.Consequently the gas may become over saturated in sulphur. Because we are below thetemperature of sulphur triple point, part of the gaseous sulphur can be transformed into solidparticles. Thus, it is important to obtain solubility data of sulphur in natural gases. Methane isthe major natural gas component. So, it is of importance to measure solubility of elementalsulphur in CH4. In this paper experimental measurements up to a pressure and temperature of30 MPA and 363.15 K are presented.The principle of the experimental pilot can be resumed following three steps: saturationof the gas with sulphur, trap of all the dissolved gaseous sulphur and finally quantification.Although the principle is simple, experimental difficulties occur at the three steps. A variablevolume equilibrium cell is used to saturate the gas with sulphur. Since sulphur solubility valueis weak in gas transport conditions, the volume of the cell is necessarily big (0.5 Litre). Thepressure of the equilibrium cell is held constant thanks to a piston during the trapping step. Anoriginal gaseous sulphur trapping method was developed. It is based on the reactiveabsorption of the gaseous sulphur with solvent. Indeed, the gas bubbles into a liquid solutionwhich traps gaseous sulphur. Finally, the solution which contains a standard is analysed bygas chromatography and sulphur is quantified. The total volume of the gas withdrawn isdetermined by a position transducer placed on the autoclave. Then, the sulphur solubilityvalue is calculated