Electrical properties of thin films of a-Ga x Te100− x composed of nanoparticles

Thin films of Ga _x Te_{100? x} (x?=?3, 6, 9 and 12) have been synthesized by thermal evaporation. From SEM images, it is observed that all the films contain nanoparticles of sizes varying from 100 to 200?nm. The dc electrical conductivity of the as-deposited films of Ga _x Te_100?x nanoparticles is measured as a function of temperature range from 298 to 383?K, and increases exponentially with temperature. The value of the activation energy, calculated from the slope of ln?σ _dc versus 1000/T plots, is found to decrease with increase in the Ga content. On the basis of the value of the pre-exponential factor σ _o, it is suggested that the conduction is due to thermally assisted tunneling of carriers in localized states near the band edges. The optical measurements suggest an indirect optical band gap in this system. The value of the optical band gap decreases on increasing the Ga concentration.     

Effect of network connectivity on thermal properties of As30Te70– x Tl x glasses

Alternating differential scanning calorimetry (ADSC) studies were undertaken to investigate the effect of Tl addition on the thermal properties of As₃₀Te_{70– x} Tl _x (6?≤?x?≤?22 at%) glasses. These include parameters such as glass-transition temperature (T _g), changes in specific heat capacity (ΔC _p) and relaxation enthalpy (ΔH ^NR) at the glass transition. It was found that T _g of the glasses decreased with the addition of Tl, which is in contrast to the dependence of T _g in As–Te glasses on the addition of Al and In. The change in heat capacity ΔC _p through the glass transition was also found to decrease with increasing Tl content. The addition of Tl to the As–Te matrix may lead to a breaking of As–Te chains and the formation of Tl⁺Te^?AsTe_2/2 dipoles. There was no significant dependence of the change of relaxation enthalpy, through the glass transition, with composition.     

Decidability of Quantified Propositional Intuitionistic Logic and S4 on Trees of Height and Arity ≤ω

Quantified propositional intuitionistic logic is obtained from propositional intuitionistic logic by adding quantifiers p, p, where the propositional variables range over upward-closed subsets of the set of worlds in a Kripke structure. If the permitted accessibility relations are arbitrary partial orders, the resulting logic is known to be recursively isomorphic to full second-order logic (Kremer, 1997). It is shown that if the Kripke structures are restricted to trees of at height and width at most , the resulting logics are decidable. This provides a partial answer to a question by Kremer. The result also transfers to modal S4 and some Gödel–Dummett logics with quantifiers over propositions.     

Defect analysis of Fe3(Al1– x Si x ) alloys by positron-lifetime spectroscopy

The recovery behaviour of vacancy-type defects created at 1000°C in Fe₃(Al_{1– x} Si _x ) alloys has been investigated by positron-lifetime measurements in samples cooled to room temperature by water quenching, air quenching and furnace cooling. In addition, a set of samples was aged for one week at 520°C. After water quenching, measurements reveal a high concentration of thermal vacancies, and from the decrease of the average positron lifetime it is inferred that vacancy recovery is strongly composition-dependent. Greater decreases of the positron lifetime were found for Si-rich samples, suggesting diffusion enhancement as the Si concentration increases. For the Fe₃Al alloy, the retained vacancy concentration depends strongly on the cooling rate. This is related to atomic ordering and a rebuilding of the D0₃ structure.     

Synthesis and evolution of crystalline garnet phases in Y3Sc5– x Ga x O12

Mixed-metal oxides with the composition Y₃Sc _x Ga_{5? x} O₁₂ (x?=?2.0, 2.1, 2.2, 2.25, 2.3, 2.4, 2.5, and 3.0) have been prepared by an aqueous sol–gel method. The effects of scandium substitution on the garnet phase formation were studied by IR spectroscopy and X-ray powder diffraction (XRD). The XRD data indicate that single-phase Y₃Sc _x Ga_{5? x} O₁₂ ceramic samples were obtained for x?=?2.0, 2.1, 2.2, 2.25, 2.3, and 2.4. The results also show that the formation of Y₃Sc _x Ga_{5? x} O₁₂ garnets depends on the molar ratio of scandium and gallium in the investigated composition, and consequently on the mean cationic radius at the Al³⁺ sites. The variation of lattice parameters for the Y₃Sc _x Ga_{5? x} O₁₂ phases with different x is reported.     

Thermal stability and glass-forming ability of Se80− x Te20Ag x (x = 0, 3, 5, 7 and 9) chalcogenide glasses

The thermal stability and glass-forming ability (GFA) of Se_{80? x} Te₂₀Ag _x (x?=?0,?3,?5,?7 and 9) chalcogenide glasses have been investigated using differential scanning calorimetry (DSC). The DSC runs have been taken at five different heating rates (10, 20, 30, 40 and 50?K/min) under non-isothermal condition. The thermal stability and GFA are monitored through determination of the temperature difference ΔT?=?T _c???T _g, where T _c is the onset crystallization temperature, T _g is the glass transition temperature, H ^l is the stability parameter, ΔH _c is the enthalpy released during crystallization and F _i is the fragility index. The activation energy of crystallization E _c and crystallization rate factor K have also been determined as indicators of the thermal stability of the above-mentioned samples. It is found that Se₇₁Te₂₀Ag₉ is the most stable among all the samples of the series.     

On the meaningfulness of behavior: An expectancy x value approach

Our research examines people’s concept of ‘meaningful behavior’ from an expectancy x value perspective. Specifically, we argue that people consider two elements when inferring the meaningfulness of behavior: the value of the goals that the behavior relates to and the degree to which the behavior is useful for the achievement of these goals. A series of five studies demonstrates that behavior is considered to be ‘meaningful’ if it is highly instrumental for a highly valued goal. Our expectancy x value approach offers a straightforward yet crucial perspective of how people infer whether or not everyday life behaviors are meaningful to them. The implications of our findings for research on meaningfulness, meaning-regulation, and sense making are discussed.     

Study of incommensurate modulation in V-doped La2Cu1- x (VO) x O4 + δ by transmission electron microscopy

Structural variations in a hole-rich grain of V-doped La₂Cu_{1? x} (VO) _x O_{4+ δ} (x?=?0.045, δ?=?0.011) superconducting compound have been studied by electron diffraction and high-resolution transmission electron microscopy. Two types of one-dimensional (1-D) incommensurate modulation were observed one after the other when the specimen was exposed to electron beam irradiation. The features of these two modulated structures have been studied and are discussed.     

Solid-solution strengthening in ordered In x Ga1 − x P alloys

Ordered In _x Ga_{1??? x} P alloys have been grown on to GaAs(001) substrates by metal–organic vapour-phase epitaxy. Lattice-matched compositions of alloys (In _x Ga_{1??? x} P with x?≈?0.5) were used in order to produce epitaxial layers free of structural defects (threading dislocations). Growth temperature and substrate orientation were adjusted to control the degree η, of order, of the alloys in the range 0.3–0.5. Nanoindentation tests were carried out to measure the mechanical response of the heteroepitaxial layers. Transmission electron microscopy was used to characterize the structure as well as the plastic zones generated into the specimen by nanoindentation. Comparison of the alloys with binary references (InP and GaP bare substrates) showed strengthening, with the hardness and flow-stress values that are much larger than those of InP and of the same order of magnitude as those of GaP.     

Does solution of mental arithmetic problems such as 2 + 6 and 3 x 8 rely on the process of "Memory updating"?

Two experiments are reported that used the selective interference paradigm to study whether, besides response selection, the process of memory updating is involved in simple mental arithmetic. Participants were asked to solve simple sums (e.g., 2 + 6, Experiment 1) or simple products (e.g., 3 X 8, Experiment 2) in a single-task control condition and in three dual-task conditions with a selective interference task, simple reactions, choice reactions, or delayed choice reactions. The role of memory updating was estimated on the basis of the difference in impairment due to the choice reaction time and the delayed choice reaction time task, whereas the difference in impairment between the simple reaction time and the choice reaction time task indicates the role of response selection. While replicating previous results concerning response selection (Deschuyteneer & Vandierendonck, 2005, in press), the study showed that memory updating is strongly involved in solving simple mental arithmetic sums and products.     

Demonstration of the g · b x u = 0 edge dislocation invisibility criterion for electron channelling contrast imaging

Dislocations with a large edge component do not exhibit a full loss of diffraction contrast in the transmission electron microscope unless the conditions g b = 0 and g b x u = 0 are simultaneously met. Because of a similarity between transmission electron microscopy (TEM) diffraction contrast and electron channelling contrast in the scanning electron microscope, the same contrast rules would be expected to apply for electron channelling contrast imaging (ECCI). Using the characteristic edge dislocations formed in annealed FeAl, it is demonstrated that the same extinction conditions apply for TEM diffraction contrast and ECCI.     

Pressure-Induced transitions in amorphous TlxSe100−x alloys

Abstract

The electrical resistivity of bulk semiconducting amorphous Tl_xSe_100?x alloys with 0 ≤ x ≤ 25 has been investigated up to a pressure of 14 GPa and down to liquidnitrogen temperature by use of a Bridgman anvil device. All the glasses undergo a discontinuous pressure-induced semiconducting-to-metal transition. X-ray diffraction studies on the pressure-recovered samples show that the high-pressure phase is the crystalline phase. The pressure-induced crystalline products are identified to be a mixture of Se having a hexagonal structure with a = 4·37 Å and c = 4·95 Å and TlSe having a tetragonal structure with a = 8·0 Å and c = 7·0 Å     

Who took the "x" out of expectancy-value theory? A psychological mystery, a substantive-methodological synergy, and a cross-national generalization

Expectancy-value theory (EVT) is a dominant theory of human motivation. Historically, the Expectancy × Value interaction, in which motivation is high only if both expectancy and value are high, was central to EVT. However, the Expectancy × Value interaction mysteriously disappeared from published research more than 25 years ago. Using large representative samples of 15-year-olds (N = 398,750) from 57 diverse countries, we attempted to solve this mystery by testing Expectancy × Value interactions using latent-variable models with interactions. Expectancy (science self-concept), value (enjoyment of science), and the Expectancy × Value interaction all had statistically significant positive effects on both engagement in science activities and intentions of pursuing scientific careers; these results were similar for the total sample and for nearly all of the 57 countries considered separately. This study, apparently the strongest cross-national test of EVT ever undertaken, supports the generalizability of EVT predictions--including the "lost" Expectancy × Value interaction.     

Severity of Types of Violations of Research Ethics: Perception of Iranian Master’s Students of Translation

Violations of research ethics including a varieties of plagiarism by students in Iran is a concern which has lately called promising levels of attention as rules are updated and better enforced and more awareness is being raised. As to deal with any problem, a full understanding of its nature is necessary, the current study focused on how a sample of Iranian students construe this phenomenon. To collect the necessary data, an original questionnaire with 34 closed-ended items included the most common instances of violations of research ethics was designed. The items included were mainly varieties of plagiarism identified in the literature. The items were narrowed down with reference to the qualitative data from focus group interviews with a purposive sample of Iranian graduate students. In the main phase of the study, using the questionnaire, quantitative data were obtained from the responses of 274 graduate students of translation studying in various Iranian universities. The findings revealed the participants did not have a fully accurate perception and appreciation of research ethics violation as they failed to distinguish ethically acceptable from unethical conducts. The contributing sample showed indifference to most ethical issues in scholarly publication. Translating a text and presenting it as one’s own in addition to text recycling were identified as the most severe instances perceived. The types, fraudulence, unacknowledged use, duplicate publication, misreferencing, excessive overuse were perceived the most severe to the least severe according to the sample. The typology and the findings on the severity of the types and instances were recommended to be used as an empirically supported guideline for curriculum design of academic writing courses in graduate programs in Iranian universities or similar contexts.     

Stress-corrosion cracking in YBa2Cu3O7−x ceramic superconductor

Abstract

Thin-foil transmission electron microscopy specimens of orthorhombic YBa²Cu³O^7?x subjected to residual elastic strains have shown slow crack growth in an atmosphere with low moisture content. Microcracks, initiated by amorphization at the strained edges, propagate alternately along (110) twin boundaries and (001) stacking faults, where strain energy is accumulated locally. The formation of carbon-rich amorphous layers along the strained lattice planes, followed by residual stress-assisted crack propagation, resembles stress-corrosion cracking in this ceramic superconductor.     

A Review of “A Dictionary of Philosophy of Religion”

ABSTRACT

HOLMAN OLD TESTAMENT COMMENTARY: EXODUS, LEVITICUS, NUMBERS. Glen S. Martin. Nashville, TN: Broadman &; Holman Publishers, 2002, 387 pp., $19.99. Reviewed by Gregg Watson.

THE WESTMINSTER DICTIONARY OF NEW TESTAMENT AND EARLY CHRISTIAN LITERATURE AND RHETORIC. David E. Aune. Louisville, KY: Westminster John Knox Press, 2003, xii, 595 pp., ISBN: 0-664-21917-9, $49.95. Reviewed by Iren L. Snavely, Jr.

ENCYCLOPEDIA OF RELIGION AND WAR, Routledge Encyclopedias of Religion and Society Series. Edited by Gabriel Palmer-Fernandez. New York &; London: Routledge, 2004, 512 pp., 33 b/w illustrations, ISBN: 0-415-94246-2, $125.00. Reviewed by Al Vara.

READING IS BELIEVING: THE CHRISTIAN FAITH THROUGH LITERATURE AND FILM. David S. Cunningham. Grand Rapids, MI: Brazos Press, 2002, 237 pp., $18.99. Reviewed by Robert F. Darden III.

UNDERSTANDING THE HADITH: THE SACRED TRADITIONS OF ISLAM. Ram Swarup. Amherst, NY: Prometheus Books, 2002, 258 pp., $22.00. Reviewed by Jeannie Colson.

AN INDEX TO ENGLISH PERIODICAL LITERATURE ON THE OLD TESTAMENT AND ANCIENT NEAR EASTERN STUDIES, Vol. VIII, ATLA Bibliography Series, 21. Compiled and edited by William G. Hupper. Lanham, MD and London: The American Theological Library Association, and The Scarecrow Press, 1999, 483 pp., $70.00. Reviewed by John Dickason.

BIOGRAPHICAL DICTIONARY OF EVANGELICALS. Editor: Timothy Larsen; Consulting Editors: David Bebbington and Mark Noll. Leicester, England and Downers Grove, IL: InterVarsity Press, 2003, 816 pp., $45.00. Reviewed by J. Michael Garrett.

LOGOS BIBLE SOFTWARE SERIES X-SCHOLAR'S LIBRARY (QB). Bellingham, WA: Logos Research Systems, 2004, $599.95, CDROM or DVD. Reviewed by Jason D. Baker.