bluuebunny/crossref_metadata_2025 huggingface dataset:
A Study in the Composition Patterns of Mycenaean Pictorial Pottery from Cyprus
Authors: Catling H. W. , Millett A.
Published: October 2013

Previous study of the relationship between provenance and composition in the Late Bronze Age painted pottery of Minoan Crete and Mycenaean Greece has shown that it is possible to distinguish a number of different types of composition which have a clearly defined territorial significance. One type of composition has been found to be characteristic of sites in the Peloponnese, two others to be almost wholly confined to north Greece, yet another to be distinctive of central Crete, and so forth. This stage of the original investigation, in fact, defined the different composition patterns which could be associated with the producing centres in the Minoan and Mycenaean homelands. But much Minoan and an even greater quantity of Mycenaean pottery has been recovered from regions far removed from these production centres. Such finds have been recorded from South Italy and Sicily, from the Ionian coast of Asia Minor, in Cyprus, Syria and Palestine, and in Egypt. A second phase of the original investigation therefore concentrated on this material. It was found, for instance, that Mycenaean pottery found in North Syria at Tell Atchana, and in Egypt at Tell el Amarna, was indistinguishable from the composition pattern (Group A) of the Mycenaean pottery from sites in the Peloponnese. This congruence was interpreted to mean that such pottery had been made in the Peloponnese and that it had travelled to Syria and to Egypt in the course of trade.
The Khaniale Tekke Tombs, II
Authors: Boardman John
Published: October 2013

Mr. R. W. Hutchinson excavated the Geometric tombs at Khaniale Tekke near Knossos in 1940. He published an account of the excavation and the material from the reused tholos (Tomb 2) in BSA xlix (1954) 215 ff. The publication in this article will often be cited below, by italicized references only. He described the finds from a chamber tomb (Tomb 1; to the right in p. 215, fig. 1). The finds from a third tomb, north of the tholos and mentioned on pp. 223 ƒ., were not available for study at that time, but were later identified, part in a storeroom at Knossos, part in Heraklion Museum, and Mr. Hutchinson kindly invited me to prepare the publication of them. Since 1954 the full publication of the Fortetsa cemetery has appeared, as well as other studies of relevant finds in the Knossos area. These prompt a reconsideration of the finds already published, especially the important gold jewellery. I have taken this opportunity to review the evidence with some supplementary photographs. St. Alexiou, Ephor of Antiquities, has kindly allowed me to study again the finds displayed in Heraklion Museum.

The contents of Tomb 1 were listed briefly on pp. 215 ƒ. They cannot now certainly be identified, but some of the pottery may have become confused with that from Tomb 3, published below. The dromos of the tholos, Tomb 2, was cut across by later burials. From one are reported an amphora (p. 224, no.23) and a lekythos of Cypriot form (possibly one of those published, pl. 26 top). Another held a wine amphora and a white-ground lekythos—fifth-century. And a third contained a pedestalled cothon with lid (no. 94). The last is in Heraklion, and is a plain plemochoe on a high flaring base.
Excavations at Kato Phana, Chios: 1999, 2000, and 2001
Authors: Beames Hugh , Tsigkou Angeliki , Wardle Nicola , Beaumont Lesley , Archontidou-Argyri Aglaia
Published: October 2013

This article presents a preliminary report on the excavation campaigns of 1999 to 2001 conducted in the Sanctuary of Apollo Phanaios at Kato Phana on Chios by the 20th Ephorate of Prehistoric and Classical Antiquities in collaboration with the British School at Athens. An account of the stratigraphy and architectural remains encountered is first presented, followed by a selected catalogue of the ceramic and small finds. The report concludes with a discussion of the chronological development of the site. While prior to the resumption of excavation work at Kato Phana in 1999 it was commonly held that the sanctuary had been established in the Late Geometric period, the new finds suggest that the history of cult worship here may extend back to the Late Mycenaean and the subsequent Protogeometric, Early Geometric and Middle Geometric periods. Excavation results now also reveal that by the seventh century BC the sanctuary had been architecturally embellished with permanent stone structures, with further architectural remodelling taking place on at least two subsequent occasions during the Archaic period. Though the paucity of Classical, Hellenistic and Roman finds from the site is puzzling, the Early Christian period provides a wealth of ceramic and small finds and architectural remains.
An early Corinthian helmet in the Manchester Museum
Authors: Jackson A. H.
Published: October 2013

The article concerns a helmet of Corinthian type, of the seventh century BC, very plain and without a crest or decoration but with small holes round the rim for stitching in a lining. It belonged for many years to Charterhouse, until that school recently sold its Museum's contents. Manchester Museum acquired it thanks to a most generous bequest from the estate of the late Professor Robert Cook. Here the helmet's dimensions and state are given; it had suffered damage particularly to the cheek-guards and the nose-guard (which is now a modern replica). Details of its design are examined, some confirming its date, others illustrating its strengths and weaknesses as a helmet. The historical significance of helmets of this plain design is briefly discussed. Finally it is suggested, on the grounds of the damage to its cheek-guards and nose-guard, that it ended its career as a victory thank-offering in a sanctuary, possibly Olympia where many helmets so damaged have been found.
Second Thoughts on ‘Mycenaean’ Pottery in Ithaca
Authors: Benton Sylvia
Published: October 2013

When I wrote my report on the excavation of Polis, Ithaca, the leader of the expedition had suggested that in Ithaca, Early Bronze Age pottery had persisted till the closing phases of the Late Bronze Age, which meant that Ithaca was a backward little place well away from the broad stream of contemporary culture. I thought it possible that there was another lag after the Late Bronze Age, and I called certain vases ‘Mycenaean,’ taking fabric to be the determining factor. My paper was written in 1932, but not published till 1942, and long before then I was sure that we were both wrong. Mr. Heurtley wished to account for the presence of fifty Mycenaean sherds in an Early Bronze Age Settlement at Pilikata. It is true that no Middle Bronze Age settlement has yet been found in Ithaca. That may be our bad fortune, or the island may have been uninhabited in the centuries before 1500 B.C., as it was in the sixteenth century A.D. It seems simpler to admit disturbance by any later diggers of foundations or seekers of wells, than to postulate an iron curtain between Ithaca and both its nearest neighbours, Kephallenia and Leukas, in the Middle Bronze Age. After all, Early, Middle, and Late Bronze Age sherds were found together in Area VI at Pilikata, and no house plans have resulted; some disturbance seems inevitable.
De L'Origine du Prisme Triangulaire dans la Glyptique Minoenne
Authors: Chapouthier Fernand
Published: October 2013

L'une des formes les plus fréquentes—et la plus originale à coup sûr—de la première glyptique crétoise est celle du prisme à trois faces décorées de motifs ornementaux ou de signes hiéroglyphiques. Comme l'abondance des specimens de ce type correspond à une absence complète du type cylindrique, si familier aux civilisations de la Mésopotamie, on a pu penser que l'un se substituait à l'autre, dérivait de l'autre. ‘Le goût crétois’, a-t-on dit, ‘répugnait à la décoration des frises indéfiniment prolongées; sitôt que l'on eut transformé le cylindre en un corps à arêtes vives et morcelé sa surface latérale en une suite de facettes, l'artisan crétois fut libre de les orner comme des unités indépendantes les unes des autres.’
The Tomb of Porsena at Clusium
Authors: Myres John L.
Published: October 2013

The Elder Pliny quotes Varro's description of the Tomb of Porsena:

Sepultus sub urbe Clusio, in quo loco monumentum reliquit lapide quadrato quadratum: singula latera pedum lata tricenum, alta quinquagenum: in qua basi quadrata intus labyrinihum inextricabilem: quo si quis improperet (introire properet v.) sine glomere lini, exitum invenire nequeat. Supra id quadratum pyramides stant quinque, quattuor in angulis, et in medio una, imae latae pedum septuagenum quinum (latae pedum quinum; ita fastigatae ut in summo aeneus petasus omnibus sit impositus M), altae centenum quinquagenum, ut in summo orbis aeneus et petasus unus omnibus sit impositus, ex quo pendeant exapta catenis tintinnabula, quae vento agitata longe sonitus referant, ut Dodonae olim factum. Supra quem orbem (supraque orbem) quattuor pyramides insuper singulae stant altae pedum centenum. Supra quas uno solo quinque pyramides, quarum altitudinem Varronem puduit adicere; fabulae Hetruscae tradunt eandem fuisse, quam totius operis: adeo vesanam dementi quaesisse gloriam impendio, nulli profuturo. Praeterea fatigasse regni vires, ut tamen (tantum v.) laus maior artificis esset.
Post-Byzantine Figured Silks
Authors: Rice D. Talbot
Published: October 2013

At one time it was generally assumed, even by distinguished Byzantinists, that the Turkish conquest of Constantinople in 1453 put a sudden stop to the production of all objects of quality in the East Christian world, and that after that date Byzantine art at once degenerated into a peasant art throughout the whole of the area touched by the Turks. Recent research has, however, led to some modification of this view, and though work of the same superb quality as that produced in the great middle period of Byzantine art was not executed, we now know that in addition to painted icons, such things as embroideries, carved reliquaries, crosses of chased metal work or champlevé enamel and objects in bone or even ivory, were produced, which were by no means negligible from the artistic standpoint. Their production continued, moreover, through the sixteenth and earlier seventeenth centuries; only after that date did Christian art in Greece and the Balkans assume an essentially ‘peasant’ character. It is indeed to the sixteenth century that the greater number of painted icons that are now to be found in museums and private collections in Greece are to be assigned, and though there was much hack-work, paintings of very high quality were also produced amongst them.
Athens and Neapolis
Authors: Meritt Benjamin D. , Andrewes Antony
Published: October 2013

We offer here for the inspection and criticism of Professor Wace a new text of the decrees passed by the Athenians late in the fifth century concerning their faithful allies the Neopolitans, who lived on the coast of Thrace where now is the modern town of Kavalla.

The larger fragments of the stone, in two groups, have been built into a bed of plaster in the Epigraphical Museum at Athens, where they bear the Inventory Number 6598 (Plate 23). A smaller fragment, which belongs to the first decree, but which cannot be fitted into a definite place in the reconstruction of the monument, bears the Inventory Number 6589 (cf. Fig.).
Part V. A Graffito from the Perseia Area
Authors: Woodhead A. G.
Published: October 2013

A visitor to Mycenae, perhaps in the middle or later part of the fourth century B.C., has left a record of his presence there in the form of a neatly-cut graffito written diagonally across a block of marble, probably a threshold found built into a wall near the Perseia fountain-house. The letters individually are well formed: they appear to diminish in size as the name progresses, but in fact do not do so: the deception may be due to a gradual rise from the horizontal line of the first three or four letters, plus a narrowing horizontal spacing. The cutting is broad and shallow, the name having, as it seems, been gouged out with some bluntish instrument measuring about 0·004 m. in width. Height of letters c. 0·03 m. Photograph (Fig.) from a squeeze now in the collection of the Museum of Classical Archaeology, Cambridge.

The name is ordinary enough, For Athenian examples see Kirchner, PA 5900–11, Hesperia, Indices s.v. etc. The best-known holder of it, not there quoted, was the potter of the late sixth century (Beazley, ARV 16, 34, 38). From the Argolid only one instance is quoted (IG IV 616.17), and that uncertain.
Thucydides as Archaeologist
Authors: Cook R. M.
Published: October 2013

In i.1–21 Thucydides gives a brief interpretation of early Greek history. This is important not only for the critical standard of its author, but also because in ten instances he says what his evidence is. Twice his evidence is archaeological. The two passages deserve careful study.

Mycenae had been destroyed by the Argives in the 460's and was deserted till the third century B.C. Thanks to modern archaeologists and Pausanias we can form some idea of what was to be seen in the time of Thucydides. Much of the Bronze Age wall, including the Lion Gate, should have been above ground; it was anyhow visible to Pausanias, and before him the Hellenistic fortifiers had made use of it. Some of the tholos tombs were open, to judge by finds made in their excavation and by Pausanias's mention of ‘underground treasuries of Atreus and his sons’. Of the Bronze Age palace and houses nothing was left above ground, so the stratification suggests. But the ruins of the city demolished in the 460's must still have survived, and its sanctuaries may have been intact; it would have been natural enough for the Argives to spare them, and there is some positive evidence that the temple on the summit of Mycenae and the sanctuary near the fountain house outside the Lion Gate were both kept in repair and that the Agamemnoneion over half a mile to the south was still visited.
A Chian Wine-Measure
Authors: Forrest W. G.
Published: October 2013

Among the Chian inscriptions collected by G. Zolotas and published by his daughter Mme Sarou in ᾿Αθηνᾶ xx (1908) 113–281 there are a few for which Zolotas relied on readings supplied by correspondents who were less careful epigraphists than himself. One of these has now appeared in Chios Museum and deserves republication.

Chios Museum (from Aplotaria in Chios town). No inv. no. Block of blue-grey Chian marble, broken off on right and bottom left. Inscribed on front face. On the top (left) a circular cavity, with raised rim, tapering downwards to a small drainage hole, and (right) a similar but larger cavity of which only a small section is preserved. The inner surface of both is carefully dressed.
The Seven Cities Offered by Agamemnon to Achilles (Iliadix. 149 ff., 291 ff.)
Authors: Simpson R. Hope
Published: October 2013

These notes are intended both as a supplement to, and as a partial correction of, my former article in this Annual, in the light of recent fieldwork in south-western Peloponnese, and of current views on the geography and place names of the Pylos Tablets. We now know that Mycenaean settlement was widespread throughout the Pamisos Valley of eastern Messenia and the western shores of the Messenian Gulf. And from the Pylos documents it has been deduced that the ‘Further Province’ of Pylos probably lay in eastern Messenia. These factors necessitate a reassessment of the Homeric tradition, particularly as regards the locations of the Seven Cities offered by Agamemnon to Achilles. I shall begin by summarizing the new archaeological information, in so far as it is relevant to the locations of the Seven Cities, before attempting an historical correlation.
Notes on the Epidaurian Building Inscriptions
Authors: Burford Alison
Published: October 2013

The building accounts of Epidauros are among the most interesting architectural and economic records of the Classical and Early Hellenistic period. It has rarely been recognized that they deserve to rank alongside the Athenian, Delphian, and Delian inscriptions, but although the Epidaurian material is slighter in bulk than the Delian, and covers a smaller area (politically and economically speaking) than the Athenian, it provides a far more comprehensive picture of that most important cultural activity, temple building. The Epidaurian inscriptions indicate the means by which one Greek city converted its sanctuary into a panhellenic cult-centre, that of the healing god Asklepios, during a period of a hundred years or so from about 370 B.C. onwards.
Dementia Care Knowledge Sharing within a First Nations Community
Authors: Forbes Dorothy , Blake Catherine , Thiessen Emily , Finkelstein Sara , Gibson Maggie , Morgan Debra G. , Markle-Reid Maureen , Culum Ivan
Published: October 2013

Cet article discute l’échantillon d’une étude des Premières Nations plus vaste sur les décisions de soins de la démence et le partage des connaissances. L’objectif de cette étude est de mieux comprendre le processus de partage des connaissances entre les praticiens de la santé (PS), les partenaires de soins, et les personnes atteintes de démence (PAD) au sein d’une communauté rurale des Premières Nations. Une méthodologie de la théorie constructiviste ancrée a été utilisée. Dix-neuf entrevues ont ete menées à trois reprises avec deux réseaux de soins de la démence qui comprenait deux PAD, trois partenaires de soins, et deux PS. Un modèle, “Partage des connaissances sur les soins de la démence,” a été conçue, centrée sur les PAD et leurs partenaires de soins. Trois grands thèmes du partage des connaissances sont representées dans le modèle: (1) le développement des relations de confiance, (2) l’accès et l’adaptation aux informations, et (3) application des informations. Des approches sensibles à la culture sont essentiels pour le développement des relations de confiance. Une fois que les relations ont été développées, le partage des connaissances grâce à l’accès, l’adaptation et l’application des informations est devenu possible.
Optimal Experimental Design With Nesting of Persons in Organizations
Authors: van Breukelen Gerard J. P.
Published: October 2013

This paper introduces optimal design of randomized experiments where individuals are nested within organizations, such as schools, health centers, or companies. The focus is on nested designs with two levels (organization, individual) and two treatment conditions (treated, control), with treatment assignment to organizations, or to individuals within organizations. For each type of assignment, a multilevel model is first presented for the analysis of a quantitative dependent variable or outcome. Simple equations are then given for the optimal sample size per level (number of organizations, number of individuals) as a function of the sampling cost and outcome variance at each level, with realistic examples. Next, it is explained how the equations can be applied if the dependent variable is dichotomous, or if there are covariates in the model, or if the effects of two treatment factors are studied in a factorial nested design, or if the dependent variable is repeatedly measured. Designs with three levels of nesting and the optimal number of repeated measures are briefly discussed, and the paper ends with a short discussion of robust design.
The Relation of Linguistic Awareness and Vocabulary to Word Reading and Spelling for First-Grade Students Participating in Response to Intervention
Authors: Kim Young-Suk , Apel Kenn , Al Otaiba Stephanie
Published: October 2013

Purpose

The relations of phonological, orthographic, and morphological awareness and vocabulary to word reading and spelling were examined for 304 first-grade children who were receiving differentiated instruction in a Response to Intervention (RtI) model of instruction.

Method

First-grade children were assessed on their phonological, orthographic, and morphological awareness; expressive vocabulary; word reading; and spelling. Year-end word reading and spelling were outcome variables, and phonological, orthographic, and morphological awareness; expressive vocabulary; and RtI status (Tiers 1, 2, & 3) were predictor variables.

Results

The 3 linguistic awareness skills were unique predictors of word reading, and phonological and orthographic awareness were unique predictors of spelling. The contributions that these linguistic awareness skills and vocabulary made to word reading and spelling did not differ by children's RtI tier status.

Conclusion

These results, in conjunction with previous studies, suggest that even beginning readers and spellers draw on multiple linguistic awareness skills for their word reading and spelling regardless of their level of literacy abilities. Educational implications are discussed.
Infrared-active spin-orbit transitions of halogen atom dopants in solid parahydrogen: The role of trapping site geometry
Authors: Hinde Robert J.
Published: October 2013

We present theoretical calculations of the 2P1/2 ← 2P3/2 spin-orbit transition of Cl dopants embedded as substitutional impurities in solid parahydrogen (pH2) matrices. In the lower-energy 2P3/2 spin-orbit level, the Cl atom's electron density distribution is anisotropic, and slightly distorts the geometry of the atom's trapping site. This distortion leads to a blue shift in the spin-orbit transition energy; the blue shift is enhanced when we account for the large-amplitude zero point motions of the pH2 molecules surrounding the Cl dopant. We also show that the intensity of the transition depends on the geometry of the trapping site. In the gas phase, the 2P1/2 ← 2P3/2 atomic transition is electric dipole forbidden. However, when the Cl atom resides in trapping sites that mimic the hexagonal close packed morphology of pure solid pH2, the transition becomes electric dipole allowed through interaction-induced transition dipole moments. These transition dipole moments originate in the anisotropic electron density distribution of the lower-energy 2P3/2 spin-orbit level.
On the mechanism of wetting failure during fluid displacement along a moving substrate
Authors: Vandre E. , Carvalho M. S. , Kumar S.
Published: October 2013

This work investigates the onset of wetting failure for displacement of Newtonian fluids in parallel channels. A hydrodynamic model is developed for planar geometries where an advancing fluid displaces a receding fluid along a moving substrate. The model is evaluated with three distinct approaches: (i) the low-speed asymptotic theory of Cox [J. Fluid Mech. 168, 169–194 (1986)], (ii) a one-dimensional (1D) lubrication approach, and (iii) a two-dimensional (2D) flow model solved with the Galerkin finite element method (FEM). Approaches (ii) and (iii) predict the onset of wetting failure at a critical capillary number Cacrit, which coincides with a turning point in the steady-state solution family for a given set of system parameters. The 1D model fails to accurately describe interface shapes near the three-phase contact line when air is the receding fluid, producing large errors in estimates of Cacrit for these systems. Analysis of the 2D flow solution reveals that strong pressure gradients are needed to pump the receding fluid away from the contact line. A mechanism is proposed in which wetting failure results when capillary forces can no longer support the pressure gradients necessary to steadily displace the receding fluid. The effects of viscosity ratio, substrate wettability, and fluid inertia are then investigated through comparisons of Cacrit values and characteristics of the interface shape. Surprisingly, the low-speed asymptotic theory (i) matches trends computed from (iii) throughout the entire investigated parameter space. Furthermore, predictions of Cacrit from the 2D flow model compare favorably to values measured in experimental air-entrainment studies, supporting the proposed wetting-failure mechanism.
Critical current density and flux pinning in Zr0.96V0.04B2 superconductor with AlB2 structure
Authors: Jung Soon-Gil , Vanacken J. , Moshchalkov V. V. , Renosto S. T. , dos Santos C. A. M. , Machado A. J. S. , Fisk Z. , Albino Aguiar J.
Published: October 2013

We have investigated the critical current density (Jc) and the flux pinning behavior in Zr0.96V0.04B2 superconductor with an AlB2 structure. V substitutions in Zr sites of non-superconducting ZrB2 system lead to superconductivity, and the 4% V-substituted Zr0.96V0.04B2 compounds show the highest superconducting transition temperature (Tc) of ∼8.7 K. The magnetic hysteresis (M−H) loops for the Zr0.96V0.04B2 demonstrate type-II superconducting behavior in a broad temperature range, and the Jc is estimated from the M−H loops using the Bean model. The analysis of the double-logarithmic Jc(H) plots indicates the dominance of collective pinning in Zr0.96V0.04B2, and that Jc(H) and magnetic field dependences of the flux pinning force density (Fp) are well fitted by the double exponential model which takes into account the existence of two superconducting gaps.
Predicting a new photocatalyst and its electronic properties by density functional theory
Authors: Sarker Pranab , Prasher Dixit , Gaillard Nicolas , Huda Muhammad N.
Published: October 2013

A new material CuBiW2O8 is reported here which is suitable for photocatalysts for solar-to-hydrogen generation by splitting water through photoelectrochemical approach. By density functional theory total energy calculations along with extensive mineral database search of relevant oxides, the crystal structures of CuBiW2O8 has been determined, which agrees well with the experimental result. We have analyzed the thermodynamical stability of this material. Its stability was found to be comparable to other well-known oxides, such as CuWO4. The band structure calculation reveals that it has a suitable band gap. In addition to this, density of states and optical absorption calculations show favorable features of a photocatalyst.
Enhancing sensitivity of force sensor based on a ZnO tetrapod by piezo-phototronic effect
Authors: Wang Zengze , Qi Junjie , Lu Shengnan , Li Peifeng , Li Xin , Zhang Yue
Published: October 2013

A force sensor based on a zinc oxide tetrapod is provided in this paper. The performance of the device was fully investigated by atomic force microscopy. Tuning Schottky barrier height by Piezo-phototronic effect leads to the increasing sensitivity of sensor from 0.17 A/N to 2.05 A/N under forward bias. The possible mechanisms have been proposed and discussed.
Monochromatizing and focussing femtosecond high-order harmonic radiation with one optical element
Authors: Ibek Mateusz , Leitner Torsten , Erko Alexei , Firsov Alexander , Wernet Philippe
Published: October 2013

A novel approach for monochromatizing and focussing the Vacuum-Ultraviolet and soft x-ray radiation from high-order harmonic generation of a femtosecond optical laser with only one optical element is presented. We demonstrate that off-axis reflection zone plates applied as focussing monochromators allow for efficiently optimizing the trade-off between energy resolution and temporal dispersion of the femtosecond pulses. In the current experimental realization, we show how the temporal dispersion can be varied between 2 fs and 16 fs with a correlating variation of the energy resolution \documentclass[12pt]{minimal}\begin{document}$\frac{E}{\Delta E}$\end{document}EΔE between 20 and 90 for an off-axis reflection zone plate optimized for harmonic 13 at 20.41 eV. We also show how the focal spot size varies correspondingly between 80 × 90 μm2 and 290 × 140 μm2 as determined with a computational fitting approach based on a 3D Gaussian model. The diffraction efficiency for the tested zone plates amounts to up to 10%. We furthermore evaluate the influence of pointing stability on the performance of the zone plates. Based on our results we propose an optimized realization of a dedicated beam line for femtosecond pulses from high-order harmonic generation with an off-axis reflection zone plate.
Determination of the spatial temperature distribution from combustion products: A diagnostic study
Authors: Kappagantula Keerti , Crane Charles , Pantoya Michelle
Published: October 2013

Temperature measurements within the highly complex reaction field of energetic materials are complicated but existing technology enables point source measurements that identify a maximum temperature at a single location. This study presents a method to extend point source measurements to thermally map the spatial distribution of temperature over a large field of interest. The method couples point source temperature measurements from a multi-wavelength pyrometer with irradiance measurements from an infrared camera to produce a highly discretized thermal map that includes the reaction and surrounding field. This technique enables analysis of temperature gradients within the field of interest and an understanding of energy propagation beyond the point of reaction. Point source measurements of maximum temperature are within 10% of reported values. The method was illustrated for the aluminum and polytetrafluoroethylene reaction and the thermal distribution of temperature produced 30 720 temperature measurements over a field of interest corresponding to 3.5 cm × 8 cm.
Visibility oscillation in a multimode laser interferometer signal and its use in optimizing path lengths
Authors: Ruden E. L. , Camacho J. F. , Lynn A. G.
Published: October 2013

The interference signal visibility V (difference to sum ratio of intensities at maximum and minimum interference) of an interferometer that uses a multimode laser is here derived for a given laser gain profile and spectral mode separation as a function of the difference ZS between the probe and reference beam optical path lengths and the spectral separation kS between the center of the laser gain profile and the nearest laser mode of higher frequency. kS has a significant effect on V for a given ZS. This parameter, in lasers where it sweeps freely across the gain profile, and other effects, such as various misalignments and optical coupling inefficiencies, render V alone an unreliable parameter for quantifying ZS (for the purpose of reducing it, say). However, the difference to sum ratio of the maximum and minimum V due to variations in kS for a given ZS is an intrinsic property of the laser insensitive to configurational details. Parameter W so defined, therefore, proves very useful for balancing path lengths. This is of particular importance for systems where probe and/or reference beams are transmitted via long single mode optical fibers, so this application is detailed. Optical path lengths within such fibers often cannot be measured to sufficient accuracy by spatial path length measurements due to fiber nonuniformity resulting in variations in the mode's group velocity (needed to convert to optical path length). Two examples are provided using different makes and models of 0.633 μm HeNe lasers with similar specifications. In the first case, the function W(ZS) is calculated directly from the laser's published gain profile and mode separation. In the second case, W is determined empirically for a range of ZS values for a laser with an unknown gain profile in a (heterodyned) interferometer whose interference signal oscillates between maximum and minimum intensity at 80 MHz due to the reference beam's optical frequency being acousto-optically upshifted by that amount, while kS spontaneously varies on an acoustic time scale. A single high-bandwidth waveform record for each ZS, therefore, provides all the information needed to determine W. Despite the second laser's gain profile apparently differing in detail, qualitative agreement is achieved between the two methods sufficient to validate the technique.
Precision platform for convex lens-induced confinement microscopy
Authors: Berard Daniel , McFaul Christopher M. J. , Leith Jason S. , Arsenault Adriel K. J. , Michaud François , Leslie Sabrina R.
Published: October 2013

We present the conception, fabrication, and demonstration of a versatile, computer-controlled microscopy device which transforms a standard inverted fluorescence microscope into a precision single-molecule imaging station. The device uses the principle of convex lens-induced confinement [S. R. Leslie, A. P. Fields, and A. E. Cohen, Anal. Chem. 82, 6224 (2010)], which employs a tunable imaging chamber to enhance background rejection and extend diffusion-limited observation periods. Using nanopositioning stages, this device achieves repeatable and dynamic control over the geometry of the sample chamber on scales as small as the size of individual molecules, enabling regulation of their configurations and dynamics. Using microfluidics, this device enables serial insertion as well as sample recovery, facilitating temporally controlled, high-throughput measurements of multiple reagents. We report on the simulation and experimental characterization of this tunable chamber geometry, and its influence upon the diffusion and conformations of DNA molecules over extended observation periods. This new microscopy platform has the potential to capture, probe, and influence the configurations of single molecules, with dramatically improved imaging conditions in comparison to existing technologies. These capabilities are of immediate interest to a wide range of research and industry sectors in biotechnology, biophysics, materials, and chemistry.
Narrow gap electronegative capacitive discharges
Authors: Kawamura E. , Lieberman M. A. , Lichtenberg A. J.
Published: October 2013

Narrow gap electronegative (EN) capacitive discharges are widely used in industry and have unique features not found in conventional discharges. In this paper, plasma parameters are determined over a range of decreasing gap length L from values for which an electropositive (EP) edge exists (2-region case) to smaller L-values for which the EN region connects directly to the sheath (1-region case). Parametric studies are performed at applied voltage Vrf=500 V for pressures of 10, 25, 50, and 100 mTorr, and additionally at 50 mTorr for 1000 and 2000 V. Numerical results are given for a parallel plate oxygen discharge using a planar 1D3v (1 spatial dimension, 3 velocity components) particle-in-cell (PIC) code. New interesting phenomena are found for the case in which an EP edge does not exist. This 1-region case has not previously been investigated in detail, either numerically or analytically. In particular, attachment in the sheaths is important, and the central electron density ne0 is depressed below the density nesh at the sheath edge. The sheath oscillations also extend into the EN core, creating an edge region lying within the sheath and not characterized by the standard diffusion in an EN plasma. An analytical model is developed using minimal inputs from the PIC results, and compared to the PIC results for a base case at Vrf=500 V and 50 mTorr, showing good agreement. Selected comparisons are made at the other voltages and pressures. A self-consistent model is also developed and compared to the PIC results, giving reasonable agreement.
Multi-dipolar microwave plasmas and their application to negative ion production
Authors: Béchu S. , Soum-Glaude A. , Bès A. , Lacoste A. , Svarnas P. , Aleiferis S. , Ivanov A. A. , Bacal M.
Published: October 2013

During the past decade multi-dipolar plasmas have been employed for various purposes such as surface treatments in biomedicine, physical and chemical vapour deposition for hydrogen storage, and applications in mechanical engineering. On the other hand, due to the design and operational mode of these plasma sources (i.e., strong permanent magnets for the electron cyclotron resonance coupling, low working pressure, and high electron density achieved) they are suitable for studying fundamental mechanisms involved in negative ion sources used in magnetically confined fusion and particle accelerators. Thus, this study presents an overview of fundamental results obtained with: (i) a single dipolar source, (ii) a network of seven dipolar plasma sources inserted into a magnetic multipolar chamber (Camembert III), and (iii) four dipolar sources housed in a smaller metallic cylinder (ROSAE III). Investigations with Langmuir probes of electron energy probability functions revealed the variation of the plasma properties versus the radial distance from the axis of a dipolar source in its mid plane and allowed the determination of the proportion between hot and cold electron populations in both chambers. These results are compared with the density of hydrogen negative ions, measured using the photodetachment technique. Electron energy probability functions obtained in these different configurations show the possibility of both hot and cold electron production. The former is a prerequisite for increasing the vibrational level of molecules and the dissociation degree and the latter for producing negative ions via dissociative attachment of the cold electrons or via surface production induced by H atoms.
Structural motifs of pre-nucleation clusters
Authors: Zhang Y. , Türkmen I. R. , Wassermann B. , Erko A. , Rühl E.
Published: October 2013

Structural motifs of pre-nucleation clusters prepared in single, optically levitated supersaturated aqueous aerosol microparticles containing CaBr2 as a model system are reported. Cluster formation is identified by means of X-ray absorption in the Br K-edge regime. The salt concentration beyond the saturation point is varied by controlling the humidity in the ambient atmosphere surrounding the 15–30 μm microdroplets. This leads to the formation of metastable supersaturated liquid particles. Distinct spectral shifts in near-edge spectra as a function of salt concentration are observed, in which the energy position of the Br K-edge is red-shifted by up to 7.1 ± 0.4 eV if the dilute solution is compared to the solid. The K-edge positions of supersaturated solutions are found between these limits. The changes in electronic structure are rationalized in terms of the formation of pre-nucleation clusters. This assumption is verified by spectral simulations using first-principle density functional theory and molecular dynamics calculations, in which structural motifs are considered, explaining the experimental results. These consist of solvated CaBr2 moieties, rather than building blocks forming calcium bromide hexahydrates, the crystal system that is formed by drying aqueous CaBr2 solutions.
Improvement of the accuracy of noise measurements by the two-amplifier correlation method
Authors: Pellegrini B. , Basso G. , Fiori G. , Macucci M. , Maione I. A. , Marconcini P.
Published: October 2013

We present a novel method for device noise measurement, based on a two-channel cross-correlation technique and a direct “in situ” measurement of the transimpedance of the device under test (DUT), which allows improved accuracy with respect to what is available in the literature, in particular when the DUT is a nonlinear device. Detailed analytical expressions for the total residual noise are derived, and an experimental investigation of the increased accuracy provided by the method is performed.
Optical emission, vibrational feature, and shear-thinning aspect of Tb3+-doped Gd2O3 nanoparticle-based novel ferrofluids irradiated by gamma photons
Authors: Paul Nibedita , Hazarika Samiran , Saha Abhijit , Mohanta Dambarudhar
Published: October 2013

The present work reports on the spectroscopic and rheological properties of un-exposed and gamma (γ-) irradiated rare earth (RE) oxide nanoparticle-based ferrofluids (FFs). The FFs were produced by dispersing surfactant coated terbium (Tb3+)-doped gadolinium oxide (Gd2O3) nanoparticles in the ethanol medium and later on they were subjected to energetic γ-irradiation (1.25 MeV) at select doses (97 Gy and 2.635 kGy). The synthesized RE oxide nanoparticles were of ∼7 nm size and having a cubic crystal structure, as predicted from transmission electron microscopy and x-ray diffraction studies. Fourier transformed infra-red (FT-IR) spectra showed an adequate blue shift of the Gd-O vibrational stretching mode from a wavenumber value of ∼558 cm−1, for the un-irradiated sample to a value of ∼540 cm−1 corresponding to the irradiated sample (2.635 kGy). In contrast, photoluminescence spectra have revealed modification of defect states along with Tb3+ assisted radiative transitions. The rheology measurements have illustrated unusual shear thinning behavior of the FFs, with an apparently improved power index (s) value from 0.34 to 0.50, obtained for increasing γ-dose cases. The variation of the decay parameter with irradiation dose, as predicted from the nature of apparent viscosity curves, is attributed to the defect formation, role of impurity ions (Tb3+), and weakening of inter nanoparticle bonding. The unusual properties of the novel RE oxide based FFs may find scope in sealing and shielding elements in the radiation environment including accelerator and other related zones.
Comment on “Temperature divergence of the dynamics of a poly(vinyl acetate) glass: Dielectric vs. mechanical behaviors” [J. Chem. Phys. 136, 154901 (2012)]
Authors: Richert Ranko
Published: October 2013

The temperature dependence of polymer dynamics below the standard glass transition is of considerable interest. Glassy relaxation dictates the process of physical aging, and understanding these slow dynamics helps in assessing a possible divergence at a finite temperature. In a recent paper, Zhao and McKenna have measured the equilibrium dynamics of poly(vinyl acetate) in the range from Tg − 15 K to Tg + 30 K using Struiks protocol [J. Zhao and G. B. McKenna, J. Chem. Phys. 136, 154901 (2012)]. In a figure that is meant to compare their results with dielectric relaxation data from Wagner and Richert [Polymer 38, 255 (1997)], dielectric retardation data from that work is shown instead. The corrected figure shows a considerable difference in the two measurements below Tg − 10 K, Arrhenius versus Vogel-Fulcher-Tammann behavior, and a possible source of the difference is discussed.
Response to “Comment on ‘Temperature divergence of the dynamics of a poly(vinyl acetate) glass: Dielectric vs. mechanical behaviors’” [J. Chem. Phys. 139, 137101 (2013)]
Authors: Zhao Jing , McKenna Gregory B.
Published: October 2013

R. Richert has made a comment to a paper of ours in which dielectric measures on poly(vinyl acetate) suggest that there is a change in temperature dependence of the temperature shift factors from Vogel-Fulcher-Tammann (VFT) to Arrhenius near to the glass transition temperature. He notes that we made an error in the description of his data and further notes that the data we did not use show a VFT behavior to well below the glass transition. Here we respond to the comment and add additional analysis that suggest that the differences in results are related to the differences between time temperature superposition (TTS) of data and fitting the data with a Kohlrausch, Williams, and Watts function. When TTS is used on the data from Wagner and Richert [Polymer 38, 255 (1997)] the change in behavior to Arrhenius-like below Tg is recovered.
Effects of deposition temperature on structure and properties of (K0.48Na0.52)NbO3 ferroelectric thin films by pulsed laser deposition
Authors: Tian Aifen , Ren Wei , Wang Lingyan , Du Huiling , Yao Xi
Published: October 2013

Highly [001] oriented lead-free (K0.48Na0.52)NbO3 thin films have been prepared on Pt/TiO2/SiO2/Si substrates by pulsed laser deposition. The microstructure and electrical properties of the thin films are a strong function of deposition temperature. Highly preferentially [001] oriented thin films were obtained at the deposition temperature of 740 °C. The film exhibits a dielectric constant of 422 and a dielectric loss of 0.058 at 1 kHz. The P-E hysteresis loop shows that the film possesses a large remnant polarization of 11 μC/cm2 and a moderate coercive field of 72 kV/cm. The Ohmic conduction is dominant at the low field for the films except the film deposited at 680 °C. However, the Poole-Frenkel conduction mechanism is dominant at the high field for the films except the film deposited at 700 °C.
Linear stability of miscible two-fluid flow down an incline
Authors: Usha R. , Tammisola O. , Govindarajan Rama
Published: October 2013

We show that miscible two-layer free-surface flows of varying viscosity down an inclined substrate are different in their stability characteristics from both immiscible two-layer flows, and flows with viscosity gradients spanning the entire flow. New instability modes arise when the critical layer of the viscosity transport equation overlaps the viscosity gradient. A lubricating configuration with a less viscous wall layer is identified to be the most stabilizing at moderate miscibility (moderate Peclet numbers). This also is in contrast with the immiscible case, where the lubrication configuration is always destabilizing. The co-existence that we find under certain circumstances, of several growing overlap modes, the usual surface mode, and a Tollmien-Schlichting mode, presents interesting new possibilities for nonlinear breakdown.
Visualization of He II counterflow around a cylinder
Authors: Chagovets T. V. , Van Sciver S. W.
Published: October 2013

We report the experimentally investigated evolution of thermal counterflow across a cylinder in He II by using a modified particle tracking visualization technique with solidified hydrogen particles as tracers. It was found, for a relatively small velocity of the normal fluid, that the flow is similar to laminar flow over cylinder in classical fluids. Increasing the flow velocity leads to the appearance of a pair of normal fluid eddies downstream the cylinder. We confirm the existence of large scale eddies both upstream and downstream of the cylinder at the highest velocities achieved. In addition to the previously reported turbulent state, we confirm the existence of a state where more than one pair of eddies coexist downstream from the cylinder.
Ideal design of textured LiCoO2 sintered electrode for Li-ion secondary battery
Authors: Yamada Hideto , Suzuki Tohru S. , Uchikoshi Tetsuo , Hozumi Masato , Saito Toshiya , Sakka Yoshio
Published: October 2013

To improve the energy density and practical realization of the all-solid-state Li-ion secondary battery, the principal requirement is a high electric conductivity in the densely sintered positive electrode. To accomplish this task, we focused on the anisotropic Li-ion and electron conductivities of the LiCoO2. As a result of our work, the ideal design of the texturing, perpendicular alignment of the c-plane and horizontal but random orientation of the c-axis on the electrode, was proposed. The battery performance of the ideal textured cell fabricated using a rotating strong magnetic field has a significantly higher performance than a randomly oriented cell.