bluuebunny/crossref_metadata_2025_split huggingface dataset:
Properties of RF magnetron sputtered gallium nitride semiconductors doped with erbium
Authors: Peřina V. , Macková A. , Hnatowicz V. , Prajzler V. , Machovič V. , Matějka P. , Schröfel J. 
Published: August 2004

AbstractGaN is a wide direct band‐gap (Eg ∼ 3.4 eV) semiconductor which is attractive for optical devices. Trivalent erbium (Er3+) is an efficient luminescent centre with an atom‐like emission at 1540 nm. Typical GaN thin films are fabricated by chemical gas‐phase deposition or by epitaxy. Our GaN films were deposited by RF magnetron sputtering using gallium targets and a 3:7 nitrogen–argon mixture. The thickness of the deposited samples was typically 1–2 µm. For Er doping, pellets of metallic Er were put on top of the Ga target. The goal of erbium doping is to reach a concentration sufficient for optical activity. The composition of prepared layers was checked by nuclear analytical methods. The GaN stoichiometry, O admixture and Er dopant up to depths of 600 nm was checked by RBS using 2.4 MeV protons and 2.2 MeV alpha particles. The H impurity was checked by ERDA with 2.7 MeV alpha particles. The structure of fabricated GaN films was checked by x‐ray diffraction, Raman spectroscopy, absorption spectra and photoluminescence spectra. The possibility of fabrication of GaN films containing Er is verified. The H concentration originating from residual contamination of the Ar–N2 mixture can be reduced to some degree by annealing. Copyright © 2004 John Wiley & Sons, Ltd.
The contribution of the amorphous phase in nanocrystalline thin films of germanium and gallium arsenide
Authors: Valeev Rishat G. , Deev Andrew N. , Ruts Yuri V. 
Published: August 2004

AbstractThe nanoscale semiconductor structures obtained by evaporation in high vacuum at different temperatures show anomalous high photoconductivity. This may be connected with the structure of clusters which can consist of both crystalline and amorphous phases. We propose a method of extracting amorphous and crystalline contributions to the clusters. This method is based on the extraction of corresponding contributions to the extended x‐ray absorption fine structure (EXAFS) spectra. The method of EXAFS spectroscopy allows information to be obtained about the local atomic structure of materials in different states, including gases and liquids. The macro‐structure of films was examined by different methods, i.e. x‐ray diffraction, transmission electron microscopy (TEM), and atomic force microscopy (AFM). We obtained the volume portion of the amorphous phase to the nanosized particles of Ge as about 70% and for GaAs about 50%. Copyright © 2004 John Wiley & Sons, Ltd.
Investigation of the electronic structure of the phosphorus‐doped Si and SiO2:Si quantum dots by XPS and HREELS methods
Authors: Kovalev A. I. , Wainstein D. L. , Tetelbaum D. I. , Hornig W. , Kucherehko Yu. N. 
Published: August 2004

AbstractThe system of the nanocrystals of Si in the SiO2 matrix (SiO2:Si) attracts a great amount of attention due to its ability for luminescence in the visible and near‐IR range of spectrum. The influence of the P ion doping was investigated for the electronic structure of the Si single crystal and the SiO2:Si nanocomposite. The P doping of SiO2 implanted with Si+ and post‐annealed at T = 1000 °C (2 h) results in the enhancement of the PL peak connected with the Si nanocrystals. Owing to the low concentration of Si nanocrystals in the SiO2 matrix, the peculiarities of the P influence on the Si electronic structure were investigated on model samples (Si single crystals with ion doping by P). The determination of the chemical state of the P impurity and the electronic structure of the P‐doped Si and (SiO2:Si) quantum dots was carried out using XPS and high‐resolution electron energy loss spectroscopy (HREELS). The experimental density of the states (DOS) in the valence band and conduction band of the SiO2:Si composite are in good agreement with the calculation of the local electronic structure around small Si inclusions in the SiO2 matrix by means of the LMTO (linear muffin‐tin orbital) method. Copyright © 2004 John Wiley & Sons, Ltd.
Phase analysis and kinetics of solid‐state ageing of Pb‐free Sn3.5Ag solder on electroless NiP substrate
Authors: Yoon Jeong‐Won , Jung Seung‐Boo 
Published: August 2004

AbstractGrowth kinetics of intermetallic compound (IMC) layers formed between Sn3.5Ag solder and electroless NiP/Cu substrates were investigated at temperatures ranging from 100 to 170 °C for 0 to 60 days. The IMC formed at the interface was mainly Ni3Sn4, and a P‐rich Ni (hereafter Ni3P) layer was also observed as a by‐product of Ni3Sn4 formation, that was localized between the Ni3Sn4 IMC and the electroless NiP deposit layer. This Ni3P layer formed because of the phosphorous accumulation at the interface between the electroless Ni and the IMC layer. It was found that both the Ni3Sn4 IMC and the Ni3P layer were formed due to the solder reaction‐assisted crystallization. Also, another layer with NiSnP was observed between the Ni3P layer and the Ni3Sn4 IMC layer. The layer thickness of Ni3Sn4 and Ni3P were approximately 1.83 and 1.56 µm after 50 days of ageing at 150°C, respectively. Copyright © 2004 John Wiley & Sons, Ltd.
Surface analysis of (NH2)2CS‐treated GaP(001) by AES and XPS
Authors: Liu K. Z. , Suzuki Y. , Fukuda Y. 
Published: August 2004

AbstractA GaP(001) surface treated by (NH2)2CS/H+ solution has been studied by Auger electron spectroscopy (AES) and XPS. The AES result indicates that the GaP(001) surface can be sulfurized by (NH2)2CS/H+ solution. Oxygen and nitrogen could be almost removed upon annealing at 550°C. The sulfur on the surface is stable below 550°C but a significant amount of carbon is left. XPS spectra of C 1s and N 1s indicate that most of the (NH2)2CS molecules are adsorbed molecularly on the surface at RT, which is consistent with the AES result. It is found that sulfur is bonded mainly to Ga atoms and also bonded to phosphorus. The XPS and AES results indicate that gallium and phosphorus oxides, which can be almost removed from the surface at 550°C, exist on the passivated surface. Copyright © 2004 John Wiley & Sons, Ltd.
Application of x‐ray photoemission electron microscopy developed at SPring‐8 BL15XU
Authors: Yasufuku H. , Yoshikawa H. , Kimura M. , Ito K. , Tani K. , Fukushima S. 
Published: August 2004

AbstractWe have been developing x‐ray photoemission electron microscopy (XPEEM) designed for measurement with both soft x‐rays and hard x‐rays at SPring‐8 beamline BL15XU, in order to realize two‐dimensional chemical analysis and to establish a technique for the micro‐area x‐ray absorption fine structure (XAFS) for practical materials. In this work, surface images of SbTe amorphous/crystalline patterned film, used as the recording layer for the digital versatile disc—rewritable (DVD + RW), were observed by XPEEM. We have also demonstrated the micro‐area x‐ray absorption near‐edge structure (XANES) of Sb LIII spectra in a 200 × 200 nm2 area by means of XPEEM, and successfully distinguished the spectrum of the amorphous bit region from that of the crystalline region. Copyright © 2004 John Wiley & Sons, Ltd.
Effect of Plasticizers on Mechanical and Barrier Properties of Rice Starch Film
Authors: Laohakunjit Natta , Noomhorm Athapol 
Published: August 2004

AbstractThe effect of plasticizers, glycerol, sorbitol and poly(ethylene glycol) 400 (PEG 400), on mechanical and barrier properties of rice starch film has been investigated. Sorbitol‐ and glycerol‐plasticized starch films appeared homogeneous, clear, smooth, and contained less insoluble particles compared to unplasticized rice starch films. PEG 400 did not form plasticized films of suitable characteristics. The softness and stickiness of films improved with increasing concentrations of glycerol and sorbitol. In general, films plasticized with glycerol and sorbitol displayed a better solubility in water than unplasticized films, i.e. 35% (w/w) glycerol and 45% w/w (sorbitol) (optimum solubility). The tensile strength of films decreased especially in the high concentration regime of plasticizers, between 20–45% (w/w) of plasticizer/rice starch film. Through the entire concentration regime, the tensile strength of glycerol‐plasticized films was significantly lower than that of sorbitol‐plasticized films, but their elongation was larger. The water vapor transmission rate (WVTR) through plasticized films and the oxygen transmission rate (OTR) increased with glycerol and sorbitol concentrations, however, glycerol was revealed to be significantly more effective in reducing the tensile strength as well as increasing the WVTR and the OTR compared to sorbitol. With the higher tensile strength and the smaller OTR and WVTR, the 30% sorbitol‐plasticized film reveals an improved coating performance in terms of a reduction of coating failures.
Physicochemical and Functional Properties of Tetraploid and Hexaploid Waxy Wheat Starch
Authors: Chakraborty Monisha , Matkovic Kornelija , Grier Dean G. , Jarabek Eric L. , Berzonsky William A. , McMullen Michael S. , Doehlert Douglas C. 
Published: August 2004

AbstractWaxy wheats possess unique starch functional properties that may be useful in specific end‐uses. To assess the physicochemical, thermal, and pasting properties, starches from seven waxy genotypes originating from two wheat classes, tetraploid durum and hexaploid hard red spring (HRS), were evaluated and compared with their counterpart non‐waxy wild types. The amylose content ranged from 2.3% to 2.6% in waxy durum lines, compared to 29.2% in normal durum control, and 2.1% to 2.4% in waxy HRS, compared with 26.0% in normal HRS control. Significant differences in the degree of crystallinity were observed between the waxy and control starches, despite similar A‐type X‐ray patterns, although differences between the two wheat classes were non‐significant. Both, control and waxy starches displayed an X‐ray peak corresponding to the amylose‐lipid complex, but the intensity of the peak was markedly lower in the waxy starches. The waxy durum starches exhibited the highest transition temperatures as measured by Differential Scanning Calorimetry (DSC), whereas, the enthalpy of gelatinization of most waxy genotypes was statistically higher than that of the controls. All waxy starches displayed high peak viscosity, high breakdown, and low setback profile as measured by the Rapid Visco Analyser (RVA). Texture analysis of RVA gels revealed significant differences between waxy and non‐waxy wheats, as well as between waxy tetraploid and hexaploid wheats, confirming that the nature and class of wheat starch would play a significant role when using waxy wheat blends in different wheat‐based products.
Endometrial development in association with ovarian follicular waves during the menstrual cycle
Authors: Baerwald A. R. , Pierson R. A. 
Published: August 2004

AbstractObjectivesWaves of ovarian follicular development during the menstrual cycle have recently been documented in our laboratory. The objective of this study was to test the hypothesis that ultrasonographically detectable changes in the endometrium during the menstrual cycle would differ between women with two vs. three waves of ovarian follicular development and among women with different major and minor wave patterns of follicle growth.MethodsFifty women of reproductive age (mean age ± SD, 28.0 ± 6.9 years) underwent daily transvaginal ultrasonography for one interovulatory interval (IOI). Ultrasonographic images of the endometrium were obtained each day, and measurements of endometrial area and perimeter (based on the shape of an ellipse, in the transverse plane) and thickness and pattern (in the sagittal plane) were recorded. Endometrial area, perimeter, thickness and pattern were compared between women with two and three waves of follicle development and among women with different minor and major wave patterns of follicular growth during the IOI.ResultsEndometrial area, perimeter, thickness and pattern increased earlier during the follicular phase in women with two vs. three waves of follicular development. In women with two follicle waves, endometrial area and perimeter increased earlier in those with major major vs. minor major follicle wave patterns.ConclusionsUltrasonographically detectable changes in the endometrium occurred in association with follicle wave dynamics in women. Earlier development of the endometrium during the follicular phase in women with two vs. three follicle waves was attributed to an earlier increase in dominant follicle estradiol production. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Das Integrationspotential mesoporöser SiO2‐Schichten als ultra‐low‐k Dielektrikum. Mesoporous SiO2 as low‐k dielectric for integration in Cu/low‐k interconnect systems
Authors: Frühauf S. , Schulz S.E. , Gessner Th. 
Published: August 2004

AbstractDie Einführung von Schichtwerkstoffen mit sehr kleiner Dielektrizitätskonstante (unter 2,2) als Isolatorschichten für Leitbahnsysteme wird für die 65nm‐Generation höchstintegrierter Schaltkreise schon in den nächsten 3 bis 5 Jahren erwartet. Infolge der Integration dieser “low‐k”‐Materialien wird eine wesentliche Verbesserung der Signalübertragungs‐eigenschaften des Leitbahnsystem ermöglicht. Bei Anwendung der Cu‐DAMASCENE‐Technologie ist eine Vielzahl von Anforderungen für technologisch relevante Eigenschaften des Isolatormaterials zu erfüllen, vor allem chemische, thermische und mechanische Stabilität. Im vorliegenden Beitrag wird das Integrationspotential mesoporöser SiO2‐Schichten als ultra‐low‐k Dielektrikum anhand des Anforderungsprofils und der erreichbaren funktionellen und technologischen Eigenschaften detailliert dargelegt.
Industrielle Vakuumlecksuche mit intelligenten Gas‐Leckdetektoren: nicht nur ein Massenspektrometer. Industrial Vacuum Leak Detection with Intelligent Gas Leak Detectors: not only a Mass Spectrometer
Authors: Große Bley Werner 
Published: August 2004

AbstractModerne Leckdetektoren, die Prüfgase, insbesondere Helium, zur Prüfung von Komponenten und Anlagen benutzen, müssen sich immer mehr an den Bedürfnissen industrieller Anwendungen orientieren. Mit einem ganz wichtigen ersten Schritt, der schon 20 Jahre zurückliegt, konnten die Heliumleckdetektoren vom flüssigen Stickstoff in der Kühlfalle loskommen, als das Gegenstromverfahren eingeführt wurde. Dies und der Ersatz von Handventilen durch mikroprozessorgesteuerte elektromagnetische Ventile ermöglichte die Bedienung durch relativ wenig ausgebildete Personen in industriellen Prozessen. In den folgenden Jahren konzentrierten sich die Anstrengungen auf die Verbesserung der Nachweisgrenze und der Heliumansprechzeit des neuen Verfahrens.Die Herausforderung durch Einführung von trockenen Pumpsystemen (von der Halbleiterindustrie gefordert) musste dabei gleichzeitig gemeistert werden. Mit den neuesten Geräten – und damit beschäftigt sich dieser Artikel hauptsächlich – wird der Betrieb unter industriellen Bedingungen jetzt optimiert, wobei man sich nun auch auf die Untergrundbehandlung konzentriert, was für schnelles Abpumpen von großen Behältern (bis zu 100l Volumen) und eindeutiges Erkennen von Lecks unter Verseuchungsbedingungen unabdingbar ist. Innerhalb weniger Minuten in den Leckratenbereich unter 1x10‐9mbarl/s beim Abpumpen eines 100 l Behälters zu gelangen, das ist eine der Spezifikationen, die erreicht werden müssen. Einige 1000 ppm Heliumuntergrund in der Umgebung oder verseuchte Elastomerdichtungen dürfen keine langen Wartezeiten ohne Wertschöpfung erzeugen.Es ist nicht überraschend, dass neben neuen Pumpentechnologien die Software ein immer wichtigerer Teil moderner Leckdetektoren ist. Es gibt inzwischen Möglichkeiten, mit Signalinstabilitäten umzugehen, um die Leckratennachweisgrenze zu verbessern, es ist möglich, den Effekt der Wasserdampfdesorption auf die Pumpzeit bei großvolumigen Behältern ohne flüssigen Stickstoff zu reduzieren, es gibt immer neue Wege, “ZERO”‐Funktionen und Kompensationen für Nichtlinearitäten bei hohen Drücken einzusetzen.Diese Entwicklungen werden erläutert und anhand einiger Beispiele von kürzlich in den Markt eingeführten Leckdetektoren verdeutlicht.
In‐situ‐Sauerstoffmesszellen für den Einsatz im Vakuum. In‐situ oxygen sensors for the use in vacuum
Authors: Hartung Reinhold , Fokkens Elgar , Möbius Hans‐Heinrich 
Published: August 2004

AbstractDer Einsatz galvanischer Zellen mit oxidionenleitenden Festelektrolyten als Sensoren im Vakuum gestattet die direkte Messung des Sauerstoffpartialdrucks, der für Redoxprozesse an der Oberfläche von Werkstücken bei Wärmebehandlungen entscheidend ist. Der Sauerstoff liegt entweder als freie molekulare Komponente oder im thermodynamischen Gleichgewicht mit anderen Gasen vor. Auch im Vakuum gelten die Grundlagen der bekannten Gaspotenziometrie. Reduzierende Gase werden in Redoxquotienten wie QH = p(H2O)/p(H2) erfasst. Für die Festelektrolytmesstechnik zu Untersuchungen im Vakuum ergeben sich spezielle Anforderungen. Sonden mit Luftbezugselektrode werden bereits kommerziell angeboten. Erprobt wurde jetzt von 1 bis 10‐7 bar das feste Bezugssystem Cu,Cu2O, das bei Sensortemperaturen zwischen 400 und 650 °C einsetzbar ist. Wesentliche Störungen durch Sauerstoffpermeabilität des Festelektrolyten wurden in diesem Temperaturbereich nicht beobachtet. Änderungen der Restgaszusammensetzung im Vakuum, die häufig infolge von Wandreaktionen auftreten, werden mit Änderungen von p(O2) bzw. QH angezeigt. Die Messgenauigkeit verbessert sich, wenn Temperaturunterschiede zwischen den Elektroden berücksichtigt werden.
Opioid medication and driving ability
Authors: Kress Hans G. , Kraft Birgit 
Published: August 2004

AbstractIn many European countries the use of opioids for long‐term treatment of nonmalignant pain has dramatically increased during the last decade in order to improve the patient's quality of life, to allow an active social life and the return to work. In modern society, driving is regarded as an essential activity of daily living. Since opioids are centrally acting drugs that may interfere with the ability of safely driving a motor vehicle, the question arises of whether or not and on which conditions patients under continuous opioid medication may be considered fit to drive. In this article the evidence from recent studies of opioid effects on driving ability of patients is reviewed. Based on these data, the prerequisites and restrictions for driving under chronic opioid medication are outlined and practical guidelines are proposed.
Psychosocial behaviour and health care utilization in patients suffering from temporomandibular disorders diagnosed on the basis of clinical findings and MRI examination
Authors: Schmitter Marc , Kress Bodo , Ohlmann Brigitte , Henningsen Peter , Rammelsberg Peter 
Published: August 2004

AbstractThe aim of this study was to evaluate psychosocial behaviour and differences in health care utilization between subgroups of patients suffering from temporomandibular disorders, using both clinical examination and magnetic resonance imaging (MRI).Materials and methods: 70 patients were examined according to the research diagnostic criteria for temporomandibular disorders (RDC/TMD), and were divided into groups according to their clinical diagnoses. MRIs were acquired and joint‐related RDC/TMD diagnoses were modified on the basis of MRI findings. Group I suffered from joint pathology, group II from myofascial pain and group III from a combination. Non‐parametric statistics were used to reveal group‐related differences in psychosocial and behavioural aspects. Differences in group assignment based on clinical and MRI examination were assessed (κ statistics).Results: MRI findings led to group assignments that were different from clinical assignments (k = 0.3). For both types of assignment, patients with myofascial pain displayed higher somatization scores, used more splints and consulted more physicians. For clinical assignment only, depression scores were higher in the myofascial pain group. For MRI based assignment, sex differences were significant between groups I and III.Conclusion: Somatization‐specific behaviour is more widespread in patients suffering from exclusively myofascial pain than in patients presenting joint pathology. Inconsistencies in differences of other psychosocial variables between groups of TMD patients seem to be related to differences in group assignment either with or without objective information on joint pathology.
Return-to-Work Interval and Surgery for Carpal Tunnel Syndrome. Results of a Prospective Series of 233 Patients
Authors: CHAISE F. , BELLEMÈRE P. , FRIL J. P. , GAISNE E. , POIRIER P. , MENADI A. 
Published: August 2004

Aim of the study To evaluate the connection between the type of patient insurance and the time taken to return to work after carpal tunnel surgery. Patients and methods Two hundred and thirty-three patients in full-time work were operated on for carpal tunnel syndrome between 1 January and 30 June 1998. They were divided into three groups: independent workers ( n=87), wage earners in the private sector ( n=90) and civil servants ( n=56). Four categories were defined: manual workers, non-manual workers, patients with social security insurance and patients with workers compensation. The average return-to-work interval after surgery for each of the groups was evaluated and compared group by group. Results For independent workers the average time off work is 17 days, for those in the private sector it is 35 days, and for civil servants it is 56 days. Patients with social security insurance were off work for 32 days and those with workers compensation for 49 days. Discussion The comparison shows significant differences with regard to social security insurance: the return-to-work interval in civil servants is larger than for private sector workers, and this is higher than in independent workers. The difference between patients with workers compensation and those with social security insurance is 17 days and significant. There is a significant difference between manual and non-manual workers in independent and private sector workers. There is no significant difference between the sub-groups in the civil servants. These cross references enable us to work out the influence that social security status has on the return-to-work time following surgery.
Perceptual Illusions in Imagery
Authors: Giusberti Fiorella , Cornoldi Cesare , De Beni Rossana , Massironi Manfredo 
Published: August 2004

A mental image is in many ways analogous to a percept but it is not completely identical to it. In some respects, visual perception and visual imagery work in different ways. One area which is worth examining with regard to similarities and asymmetries between perception and imagery is the initial phases of visual information processing. The literature includes some references to the equivalence of imagery and perception in optical illusions, but data are contradictory. In our view, a mental image should not be particularly sensitive to variables which are critical in producing an optical illusion, i.e., variables affecting the early phases of information processing and field global effects. Our hypothesis is that an optical illusion will be present in a perception condition but not in an equivalent imagery condition. To test this, we carried out two experiments using the Ebbinghaus illusion and the Ponzo illusion. The results confirmed our hypothesis, demonstrating that there are indeed asymmetries between perception and imagery and that such differences mainly concern specific perceptual processes that differ from those involved in the generation of a mental image.