bluuebunny/crossref_metadata_2025_split huggingface dataset:
Der Einfluß kleiner Kohlenstoff‐ und Iridium‐Gehalte auf die Versetzungssubstruktur in Molybdän‐Einkristallen
Authors: Balan V. Z. , Barthel J. , Göbel R. , Jurisch M. , Matvienko L. F. , Ovsienko D. E. , Sosnina E. J. 
Published: July 2007

AbstractEs wurde der Einfluß der Züchtungsbedingungen und kleiner Kohlenstoffzusätze auf die Versetzungssubstruktur in Molybdän‐Einkristallen hoher Reinheit sowie der Zusammenhang zwischen dem Verteilungstyp von Iridium‐Verunreinigungen und der Substruktur dotierter Mo‐Einkristalle untersucht. Für die Untersuchungen wurden autoradiographische und röntgenographische Methoden angewendet. In der Arbeit wird gezeigt, daß Kohlenstoff die Perfektion der Einkristalle wesentlich verschlechtert. Im Falle der Ir‐dotierten Einkristalle spielt der Verteilungstyp der Beimengungen (B‐Kerne, A‐, B‐Streifen/Zellen) eine entscheidende Rolle.
Kinetics of sodium fluosilicate precipitation
Authors: Söhnel O. 
Published: July 2007

AbstractThe formation of Na2SiF6 by discontinuous precipitation of dilute H2SiF6 with a 40% excess of an aqueous solution of NaCl under various conditions was studied. The values of induction time, number of crystals formed, their final size and their habit were determined during precipitation from solutions, whose initial supersaturation was 2 < S < 11. At S < 7–8 the crystals were formed by heterogeneous nucleation, whereas at S ≳ 7–8 homogeneous nucleation mechanism began to prevail. Once formed, the Na2SiF6 crystals were growing according to the screw‐dislocation mechanism till they reached visible size; the corresponding values of kinetic order of nucleation and of the growth rate constant were g = 1.35 and kg = 4.32 × 10−8 cm2.05 sec−1 g−0.35, resp. The value of interfacial tension on the phase boundary Na2SiF6 crystal — saturated solution was determined (σ ∼ 52 erg/cm2). The resulting Na2SiF6 crystals conformed to log‐normal distribution irrespective of conditions of precipitation. The dependence of the final size of crystals on supersaturation exhibited a maximum at S ∼ 6. Crystals of Na2SiF6 had a hexagonal habit, which was near to a spherical form at lower supersaturations, while dendritic crystals were formed at higher supersaturations.
Untersuchungen zur Konzentration und Ausheilkinetik von Kristallbaufehlern in Metallen mit Hilfe der Positronenannihilation. Kurzer Abriß und Literaturübersicht
Authors: Dlubek G. 
Published: July 2007

AbstractEs erfolgt eine kurze Darstellung der Grundlagen und der Anwendung der Positronenannihilation zur Untersuchung von Kristallbaufehlern in Metallen, die ergänzt wird durch eine thematisch gegliederte Übersicht über neuere Literatur.
Single crystal growth of La2(SO4)3 · 9 D2O
Authors: de Saja J. A. , de Saja A. , Pastor J. M. , Rull F. 
Published: July 2007

AbstractSingle crystals of La2(SO4)3 · 9 D2O were grown from saturated D2O solutions. According to X‐ray diffraction measurements, the crystals have a hexagonal structure with unit cell parameters a = 10.996 Å and c = 8.077 Å (space group C–P63/m). Several physical properties were also determined (density, refractive indices, dielectric constants, specific heat, coefficient of linear expansion, microhardness).
Strukturierung und Verhalten von AuGaSb‐Kontakten
Authors: Vogel Klaus K. , Engel Aribert 
Published: July 2007

AbstractDer Einfluß der Herstellungsbedingungen von Au‐Kontakten auf ihre Struktur und das elektrische Verhalten wurde an p‐ und n‐GaSb untersucht. Die nach Czochralski gezogenen GaSb‐Proben haben (111)‐Orientierung und sind mit p = 2–5 · 1017 cm−3 eigenleitend bzw. mit n = 4–8 · 1017cm−3 Te‐dotiert. Besonders wurde der Einfluß verschiedener Nachbehandlungstemperaturen zwischen 20°C und 400°C auf die Kontakteigenschaften studiert. An den hergestellten Au‐Kontakten erfolgten Widerstandsmessungen nach der Vierspitzenmethode. Es wurde eine Änderung des Kontaktwiderstandes in Abhängigkeit von der Nachbehandlungstemperatur und vom eingesetzten Drahtkontaktierverfahren festgestellt.
Funktionelle Abhängigkeiten der Gleichgewichtsverteilungskoeffizienten in Molybdän
Authors: Duží Pavel 
Published: July 2007

AbstractAus einer genaueren Untersuchung der Periodizität der Gleichgewichtsverteilungskoeffizienten in Molybdän geht hervor, daß die ko‐Werte der Beimengungen in Mo von drei Haupteinflußfaktoren abhängen vom a) Valenzfaktor (Anzahl der Valenzelektronen), b) Größenfaktor (Differenz der Atomradien von Mo und Beimengung), c) Gitterstabilitätsfaktor (die wirklichen oder hypotetischen Schmelzpunkte TM des mit Hauptmetall identischen Gitters des Fremdelementes). Nach dieser Abhängigkeit können die kc‐Werte der Beimengungen, für die keine oder ungenaue Zustandsdiagramme mit Mo vorliegen, vorhersagt oder prezisiert werden.
Gitterkonstantenänderungen und chemische Inhomogenitäten von tetragonalem ZnSiP2
Authors: Günther F. , Oettel H. , Stündl P. , Heide G. 
Published: July 2007

AbstractLokale Gitterkonstantenänderungen in ZnSiP2‐Kristallen, die mit Hilfe der Bond‐Methode nachgewiesen wurden, belegen örtliche chemische Inhomogenitäten, die mit Si‐Konzentrationsänderungen bis zu etwa 0,8 At.‐% erklärt werden können.
Zur Versetzungsdichtemessung von GaAs‐Einkristallen mit dem automatischen Gefügeanalysator EPIQUANT
Authors: Richter H. 
Published: July 2007

AbstractDer Einfluß der EPIQUANT‐Einstellgrößen auf die Meßgenauigkeit der Versetzungsdichte der GaAs‐>100<‐Kristalle wird beschrieben und eine Methode zur Bestimmung der mittleren Größe der Versetzungsätzgruben aus der Schnittlängenklassierung dargelegt. Spezielle linearanalytische Messungen zur Anordnung der Versetzungen auf dem Kristallquerschnitt und zur Größenverteilung der Versetzungsätzgruben ergeben wertvolle Hinweise auf die Perfektion des Einkristalls.
Morphologische Untersuchung von synthetischen Diamanten
Authors: Vavrda Josef 
Published: July 2007

AbstractMittels Röntgenstrahlbeugung wurde die Desorientierung der Subkörner von Diamantkristalliten untersucht. Der Zusammenhang zwischen der Ausscheidung von Katalysator‐Begleitphasen, Desorientierung von Subkörnern und Zwillingsbildung bzw. Aggregation von Diamantkristalliten wurde festgestellt.
Diffraktometrische Substrukturanalyse
Authors: Oettel H. 
Published: July 2007

AbstractStarting from the work of WARREN about the influence of grain size on intensity fluctuations of X‐ray interferences simple relations between these fluctuations and substructure parameters as subgrain size and desorientation are derived. As can be shown measurements with different beam divergencies allow to estimate subgrain size and desorientation separately. Combined X‐ray and TEM investigations on deformed and annealed armco‐iron show the usefulness of the proposed method of diffractometrical substructure analysis.
Optimierung der quantitativen röntgenographischen Phasenanalyse
Authors: Fiala Jaroslav 
Published: July 2007

AbstractEs wird ein neues Verfahren der absoluten quantitativen röntgenographischen Phasenanalyse auf der Basis der quadratischen Programmierung beschrieben, das optimale analytische Resultat garantiert. Die theoretischen Schlußfolgerungen werden durch ein praktisches Beispiel illustriert.
The defect structure of CdS crystals heavy doped with Cu, Se. and Zn atoms
Authors: Bak J. , Demianiuk M. , Żrmija J. 
Published: July 2007

AbstractIn this paper the defect structure of CdS crystals doped with Cu, Se and Zn atoms has been investigated. There were used two X‐ray methods: the oscillating slit and oscillating film methods. CdS crystals were obtained from the melt under pressure of Se and Zn 0.5, 0.75, 1% wt and Cu 0.25, 0.5, 0.75, 1% wt in relation to CdS crystals. It was proved that high doping damages the structure of CdS crystals and that especially Cu impurity much more disturbs the crystal lattice than Zn one. Se atoms cause rather small deformation of crystal and increase the lattice constant, this being connected with decreasing of energy gap.
Die Phasenübergänge und die Störstellenphotoleitung von Sb2S3
Authors: Grigas J. , Urbonawitschius W. , Orliukas A. 
Published: July 2007

AbstractEs wird die Abhängigkeit der Dielektrizitätskonstante und Photoleitfähigkeit von Sb2S3‐Kristallen von den Züchtungsbedingungen dargestellt. Es wird gezeigt, daß an Kristallen mit einer hohen Dielektrizitätskonstante, die spontane Polarisation aufweisen, auf der ferroelektrischen Fläche eine Störstellenphotoleitung beobachtet wird.
The thermal decomposition of aluminium hydroxide doped with Fe(III) ions
Authors: van Dijk J. 
Published: July 2007

AbstractThe thermal decomposition of various aluminium hydroxides doped with Fe(III) ions has been studied using ESR. The transition aluminas (η, γ, ϰ‐Al2O3) formed at low calcination temperatures show the ESR‐spectrum characteristic for Fe(III) ions incorporated in low crystalline materials. Spectra of doped reference compounds (ZnAl2O4, MgAl2O4, (dis)ordered LiAl5O8) showed that disorder in the cation sublattice could be responsible for this feature. The ESR spectra of aluminas (θ, x, α‐Al2O3) formed at high calcination temperatures reveal well‐defined and characteristic fine structures. Comparison with reference compounds (β‐Ga2O3, α‐Ga2O3) allows to draw conclusions as to the structure. The quality of the spectrum of δ‐Al2O3 formed in the dehydration sequence of boehmite, was in between that of the low and high temperature aluminas. In order to explain some of the features observed in the various dehydration sequences, a discussion based on the coordination of the anions along lines pointed out by GORTER, has been put forward. To this end, the regularity of the anion coordination is followed within the special packing sequences of the anion layers in the dehydration products.
Untersuchung dünner Isolatorschichten in Sandwich‐Anordnungen mit dem Elektronenspiegel‐Mikroskop
Authors: Heydenreich J. , Godehardt R. , Vester J. 
Published: July 2007

AbstractEs werden bei Elektronenspiegel‐Untersuchungen von Au–SiOx–Ge‐Sandwich‐Systemen beobachtete charakteristische Bildstrukturen beschrieben, die durch Leitfähigkeitsinhomogenitäten in der Isolatorschicht hervorgerufen werden. Durch eine quantitative Auswertung der experimentellen Ergebnisse ist eine Abschätzung der Ausdehnung und der Stärke der Inhomogenitäten möglich.
Computer generation of composite X‐ray powder patterns. A BESM‐6 FORTRAN program and its application to special problems of quantitative phase analysis
Authors: Fichtner‐Schmittler H. , Fichtner K. 
Published: July 2007

AbstractA computer program for the calculation and schematic representation of X‐ray diagrams of a polycrystalline substance or mixture of substances is outlined. The generation of X‐ray powder patterns is based on input data characterizing the crystal structures (lattice constants, atomic positions, etc.) and the features of the diagrams (diffractometer or Guinier type; line shape, resolution). Three examples illustrating the application of the program are discussed.
α‐substituted Phosphoryl Compounds (II). The Crystal and Molecular Structure of Diphenyl‐[5,6‐dichloro‐1, 3‐benzodioxol‐(2)]‐phosphine‐oxide, C19H13O3PCl2
Authors: Kulpe S. , Seidel I. 
Published: July 2007

AbstractThe compound crystallizes in the monoclinic space group P 21/c with four molecules per unit cell, and with the lattice parameters a = 11.807 Å, b = 13.070 Å, c = 11.312 Å, β = 96.74°. With X‐ray diffraction data collected on a four circle diffractometer, the crystal structure has been determined by direct methods and refined to an R‐value of 0.061 for 2735 measured and symmetrically independent reflections. The substance is a derivative of acetales of formyl diphenyl phosphine oxides. Correlations between the geometry of the structure and NMR‐data are of interest.
Crystal and Molecular Structure of Piperidinium‐acet‐m‐Cl‐anilide‐chloride
Authors: Reck G. , Leibnitz P. 
Published: July 2007

AbstractPiperidinium‐acet‐m‐Cl‐anilide‐chloride crystallizes in the orthorhombic space group Pca21 with 4 formula units C13H18ON2Cl2 in the unit cell. The lattice parameters are a = 10.348 Å, b = 12.280 Å and c = 11.335 Å. The crystal structure was determined by the heavy atom method and refined by least‐squares procedures to the conventional R = 0.045. Bond lengths, bond angles and the conformation of the drug molecule were determined. Cl− ions are linked to the molecules by hydrogen bonds forming chains together with iones and molecules related by the a‐glide plane.
Structural Properties of S‐alkylated Dithiolene Chelates (II). Crystal and Molecular Structure of Tris‐(S‐methylethene‐1,2‐dithiolato)cobalt
Authors: Richter R. , Sieler J. , Kaiser J. 
Published: July 2007

AbstractThe crystal and molecular structure of tris(S‐methyl‐ethene‐1,2‐dithiolato)cobalt has been determined by X‐ray structure analysis. The substance crystallizes in the cubic space group Pa3 with a = 14.545 Å and 8 formula units per unit cell. The structure was solved by heavy‐atom technique and refined to a final R value of R = 0.11. The co‐ordination polyhedron of this trischelate is a slightly distorted octahedron. The distances from the cobalt atom to thioether‐sulphur atoms and to mercaptide‐sulphur atoms differ significantly. The methyl groups are arranged in a facial (cis) manner. The molecule has the symmetry C3. The substance shows great structural similarity to anionic tris(dithiolene) chelates.
Interdiffusion in FCC Ni‐in alloys
Authors: Budurov S. J. , Boshinov W. S. , Kovatchev P. D. 
Published: July 2007

AbstractIt is the purpose of this study to add direct diffusion data to the results obtained from the cellular precipitation kinetics in earlier papers (BUDUROV et al.) The values of the interdiffusion coefficients were determined in the temperature range from 900° to 1100°C, using conventional diffusion couples and an electron microprobe.
The kinetics of crystal growth of succinonitrile and cyclohexanol from the melt
Authors: Alfintsev G. A. , Chemerinsky G. P. , Fedorov O. P. 
Published: July 2007

AbstractThe crystal growth kinetics of two organic substances with low melting entropies — succinonitrile and cyclohexanol — was studied in the wide range of supercoolings. The values of kinetic coefficients which connect growth velocity and interface supercooling are equal to 0.17 – 0.72 m/(s · K) for succinonitrile and (1.6 – 2.0) · 10−4 m/(s · K) for cyclohexanol. Viscosity of these substances was measured to compare the experimental data with theoretical dependences for continuous growth. It has been found that experimental kinetics of substances under study differs significantly from the expression of Wilson‐Frenkel type.
Treatment of data on metastable zone width leading to nucleation characteristics and measurements in the system potassium dichromate‐water
Authors: Nývlt J. 
Published: July 2007

AbstractMeasurements of the width of metastable zone can be used for characterisation of the kinetics of nucleation. Methods of treatment these data discussed in literature are summarised, re‐examined and arranged in order to enable smoothing of experimental data and simultaneous calculation of the values of certain characteristic nucleation parameters. An example (potassium dichromate in aqueous solution) shows that the values obtained in this way are within usual limits given in the literature. The results indicate that in unseeded solutions the nucleation was probably heterogeneous one, whereas in presence of a fixed seed an adsorbed layer mechanism of secondary nucleation followed by a fluid shear action seems to explain the results.
Growth and characterization of SSD InP crystals used as substrates for infra‐red LED's
Authors: Moravec F. , Novotný J. , Janáček J. 
Published: July 2007

AbstractBulk indium phosphide crystals have been grown by the synthesis, solute diffusion (SSD) method. Various growth temperatures and temperature gradients in the indium melt were investigated. The growth temperature of about 850–900°C and the temperature gradient of about 10–15°C cm−1 were found as the most suitable growth conditions. All grown crystals were of the n‐type either undoped or doped with Te or Sn. Infrared light‐emitting junctions were grown by single LPE process. Characteristic surface structures of InP epitaxial layers as a function of the growth temperature and cooling rate were observed. Efficiencies of LED's have been typically 0.8%. Single LPE process on LEC InP substrates has given LED's with substantially lower efficiencies.
Nucleation in quiet supersaturated ADP solutions
Authors: Nagalingam S. , Vasudevan S. , Ramasamy P. , Laddha G. S. 
Published: July 2007

AbstractThe nucleation study has been made with supersaturated ADP solution. Rate of nucleation as indicated by the induction period was measured for non‐agitated system over the temperature range 20°C–45°C. The nucleation rate increases with increase in temperature but supersaturation has the dominant effect as predicted by classical nucleation theory. However, attempts to analyse the results in accordance with classical theory were not entirely successful, but it is shown how the assumption of (a) a variation of crystal surface energy with temperature and (b) the influence of heterogeneous nucleation can account for the discrepancies. Activation energies, surface free energies and sizes of crystal nuclei were determined for nuclei of ammonium dihydrogen orthophosphate over the range of temperature 20°C–45°C.
Effect of γ‐irradiation on the lattice parameter and colour centre concentration in pure Ca2+, Sr2+ and Eu2+ doped KCI crystals
Authors: Damm J. Z. , Stepień‐Damm J. 
Published: July 2007

AbstractThe changes of lattice parameter and colour centre concentration are examined in KCI crystals (both pure and Me2+‐doped) irradiated by γ‐rays at room temperature. For the pure crystals the relative volume change vs. F‐centre concentration plot reveals the presence of two stages, one ascribed to the introduction of colour centre pairs (or F centres only) and other to the generation of the new dislocations (or new dislocations with trapped‐hole centres). In Me2+ doped crystals the lattice expansion bears a complex character (in the initial irradiation stage a transient maximum appears). Additional anomaly appears in Eu2+ KCI in the high‐dose range where in spite of a distinct F‐centre concentration drop a marked raise of the lattice parameter is observed.
Effect of some Me2+ impurity ions on the lattice parameter of KCI crystals
Authors: Stepień‐Damm J. , Łukaszewicz K. 
Published: July 2007

AbstractThe effect of concentration of substitutional Ca2+, Sr2+, Ba2+ and Pb2+ ions on the lattice parameter of KCI crystals is examined. The amount of lattice contraction induced by the alcaline earths ions qualitatively correlates with the pertinent ionic radii values (relative unit cell contraction induced by one impurity dipole amounts to −0.905, −0.110 and −0.020 for Ca2+, Sr2+ and Ba2+ ions, respectively). The initial drop of lattice parameter observed at low Me2+ concentration is tentatively ascribed to the drop of dislocation density. In Pb2+ doped crystals except for the above initial drop, at higher dopant concentration no effect upon the lattice parameter is found.
Phase diagram and single crystal growth of the CuInSe2xS2(1−x) solid solutions
Authors: Bodnar I. V. , Bologa A. P. , Korzun B. V. 
Published: July 2007

AbstractThe phase diagram of the CuInSe2‐CuInS2 system is plotted using DTA and the solidus and liquidus lines by the approximation of the theory of regular and ideal solutions are calculated. The single crystals of the CuInSe2xS2(1−x) solid solutions are first grown by chemical transport.
Character of indirect exchange interactions in lanthanum manganite
Authors: Karavay A. P. , Sirota N. N. , Pavlov V. I. 
Published: July 2007

AbstractUsing the neutron diffraction and magnetic studies a model for exchange interactions in lanthanum manganite with altering ranges having antiferromagnetic and ferromagnetic ordering in the crystal structure is suggested. The anisotropic exchange interaction of the Mn3+ O2− Mn3+ type, accompanied by the local Jahn‐Teller oxygen octahedron distortions, dominates in antiferromagnetic ranges, while in the ferromagnetic ones there are two types of positive exchange interactions: Mn3+ O2− Mn4+, the mechanism of which has been proposed by Zener, and Mn3+ O2− Mn3+ without the local Jahn‐Teller distortions.
An experiment to evaluate methods for estimating fossil fuel resources
Authors: Sterman John D. , Richardson George P. 
Published: July 2007

AbstractEstimates of petroleum and natural gas resources vary substantially, both over time and across estimation methods. This paper develops a simulation model of global oil resources to evaluate different resource estimation techniques. Protocols for the Hubbert life cycle and USGS geological analogy methods are developed and applied to synthetic data generated by the model. It is shown that the Hubbert method can generate an accurate estimate as early as twenty years before the peak of global production, but the geological analogy approach overestimates the true resource base over the life cycle of the resource. The results show the applicability of simulation and the synthetic data approach to the problem of evaluating forecasting methods.
Forecasting capacity and capacity utilization in the U.S. aerospace industry
Authors: Greer Wlllls R. , Liao Shu S. 
Published: July 2007

AbstractThe forecasting of capacity and its utilization is particularly relevant in the aerospace industry because of long product delivery lead‐times and the forward‐pricing system. The objective of this paper is to develop a method for forecasting both the industry's capacity and its capacity utilization so that decision makers who must rely on this information may have policy guidance. The result shows that the aerospace industry's capacity expansion rate is closely tied to its present and recent past state of capacity utilization, and to anticipated changes in output. Output, in turn, can be predicted by using Five Year Defense Plans data and information on the cyclical nature of commercial business. Based on these findings, we were able to build an accurate model for forecasting aerospace industry capacity utilization.
Bushfire rate‐of‐spread forecasting: Deterministic and statistical approaches to fire modelling
Authors: Beer T. 
Published: July 2007

AbstractThe three basic modelling approaches used to explain forest fire behaviour are theoretically, laboratory or empirically based. Results of all three approaches are reviewed, but it is noted that only the laboratory‐ and empirically based models have led to forecasting techniques that are in widespread use. These are the Rothermel model and the McArthur meters, respectively. Field tests designed to test the performance of these operational models were carried out in tropical grasslands. A preliminary analysis indicated that the Rothermel model overpredicted spread rates while the McArthur model underpredicted. To improve the forecast of bushfire rate of spread available to operational firefighting crews it is suggested that a time‐variable parameter (TYP) recursive least squares algorithm can be used to assign weights to the respective models, with the weights recursively updated as information on fire‐front location becomes available. Results of this methodology when applied to US Grasslands fire experiment data indicate that the quality of the input combined with a priori knowledge of the performance of the candidate models plays an important role in the performance of the TVP algorithm. With high‐quality input data, the Rothermel model on its own outperformed the TVP algorithm, but with slightly inferior data both approaches were comparable. Though the use of all available data in a multiple linear regression produces a lower sum of squared errors than the recursive, time‐variable weighting approach, or that of any single model, the uncertainties of data input and consequent changes in weighting coefficients during operational conditions suggest the use of the TVP algorithm approach.