bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cyclic interaction between normal and shear stresses of an epoxy polymer—Experiments and model predictions
Authors: Xia Zihui , Shen Xinghe , Ellyin Fernand 
Published: December 2009

AbstractThis investigation focuses on the axial‐torsional loading interaction of an epoxy polymer, Epon 826/Epi‐Cure Curing Agent 9551. Thin‐walled tubular specimens were subjected to combined constant tensile (or shear) stress and cyclic shear (or tension) loading schemes. Pure tensile creep and shear creep tests were also performed to compare the creep deformation to that with superimposed cyclic shear or cyclic tension. Test data clearly showed that cyclic shear (or cyclic tension) have a readily discernible effect on the tensile (or shear) creep deformation. Similarly, a superimposed constant tensile (or shear) load affects the hysteresis responses in cyclic shear (or cyclic tension). A nonlinear constitutive model developed by the authors was used to simulate the observed normal‐shear stress interaction. Due to the inclusion of an effective stress parameter in its nonlinear function, this model was able to account for the normal‐shear coupling effect. However, the incorporation of a general loading/unloading rule led to inaccurate simulation of the observed oscillatory creep response. A modification of the general rule was proposed and better predictions on both the cyclic and the creep responses could be obtained. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Electrical characterization of the boron trifluoride doped poly(3‐aminoacetophenone)/p‐Si junction
Authors: Yakuphanoglu Fahrettin , Şenkal B. Filiz 
Published: December 2009

AbstractElectrical and interface state properties of the borontrifluoride doped poly(3‐aminoacetophenone)/p‐Si junction have been investigated by current‐voltage and impedance spectroscopy methods. Al/p‐Si/P3APBF3/Aldiode indicates a nonideal behavior with electrical parameters (n = 3.53, ϕB = 0.82 eV, and Rs = 1.48 kΩ), which result from the interfacial layer, series resistance, and resistance of the organic semiconductor. The obtained barrier height value of the Al/p‐Si/P3APBF3/Aldiode is higher than that of the conventional Al/p‐Si (ϕB = 0.58 eV) Schottky diode. The interface state density of the diode was of the order of 1.05× 1012 eV−1 cm−2. It is evaluated that the barrier height and interface state density values of the diode are modified using the boron trifluoride doped poly (3‐aminoacetophenone) organic semiconductor. POLYM. ENG. SCI., 2010. © 2009 Society of Plastics Engineers
Management of multiple sclerosis during pregnancy
Authors: Brookings William , Lee Martin 
Published: December 2009

AbstractIn Pregnancy is a series of reviews focusing on the management of women with psychiatric and neurological conditions during pregnancy. In this article, Dr Brookings and Dr Lee describe how pregnancy can affect the course of multiple sclerosis (MS),discuss the safety of MS therapies and highlight other management issues to consider during pregnancy and postpartum. Copyright © 2009 Wiley Interface Ltd
Parkinson's Disease Society 6th Spring Conference for Researchers
Authors: Bedford Lynn 
Published: December 2009

AbstractThe Parkinson's Disease Society's 6th Spring Conference for Researchers was held in London in May, entitled ‘Parkinson's Disease:The Pieces of the Puzzle’. Here, Dr Lynn Bedford, Parkinson's Disease Society Senior Research Fellow, reports on some of the highlights of the conference, including the latest genetic research, the importance of pre‐motor symptoms and the therapeutic potential of the peptide exendin‐4, found in the saliva of a poisonous lizard. Copyright © 2009 Wiley Interface Ltd
The pharmacological management of anxiety disorders
Authors: Bleakley Stephen 
Published: December 2009

AbstractProgress in Neurology and Psychiatry is running a series of articles on the major psychiatric drug groups, produced in association with the College of Mental Health Pharmacists. In this article, Stephen Bleakley provides an overview of the main types of anxiety disorder and the efficacy and side‐effects of the drugs recommended for the treatment of these disorders. Copyright © 2009 Wiley Interface Ltd
NICE focuses on depression in chronic ill health
Authors: Titmarsh Steve 
Published: December 2009

AbstractIdentifying and treating depression in adults with chronic physical health problems (including neurological disorders) is highlighted in a new clinical guideline from the National Institute for Health and Clinical Excellence (NICE).1 The new guideline is linked with an updated version of NICE's depression clinical guideline.2 SteveTitmarsh reports from a Press briefing held in London to announce the new guidelines. Copyright © 2009 Wiley Interface Ltd
Errors in the recognition and diagnosis of sleep disorders
Authors: Stores Gregory 
Published: December 2009

AbstractThe lecture ‘Sleep Disorders ‐ an Update for Psychiatrists’ was given by Professor Gregory Stores at the eighth Latest Advances in Psychiatry Symposium in London in March. Professor Stores discussed the fact that sleep disorders can often be misinterpreted as psychiatric disorders, and in this article, he provides more information on this often‐neglected topic. Copyright © 2009 Wiley Interface Ltd
Educating staff about delirium in an acute hospital setting
Authors: Law Emma , Connelly Peter , Prentice Neil , Rooke David 
Published: December 2009

AbstractDelirium is often underdetected or misdiagnosed within the hospital setting. Here, the authors present the results of their study to assess whether a simple educational programme delivered to nursing staff within their District General Hospital can improve the rate of detection of delirium. Copyright © 2009 Wiley Interface Ltd
The development and impact of insomnia on cancer survivors: a qualitative analysis
Authors: Fleming Leanne , Gillespie Stephanie , Espie Colin A. 
Published: December 2009

AbstractObjectives: To conduct the first qualitative analysis of the development and impact of insomnia on a cohort of cancer survivors.Methods: Twenty‐one cancer survivors with a history of chronic insomnia contributed to four focus groups held at the University of Glasgow Sleep Research Centre. Participants' perceptions of the onset, evolution and effects of insomnia were elicited and qualitatively explored using content analysis.Results: Most participants reported insomnia onset following cancer diagnosis. Participants who had a pre‐existing insomnia reported that cancer diagnosis significantly aggravated their sleep complaint. Active cancer treatment was a major contributor to poor sleep quality due to the disruption of normal daily routines. This poor sleep pattern became persistent once active treatment had ceased and participants reported becoming particularly concerned about their sleep when they were discharged into follow‐up cancer care. The impact of insomnia was significant for all participants in the study and six major areas emerged as being particularly affected; mood, physical health, relationships, sleep quality, sleep‐related behaviour and cognition.Conclusions: The majority of cancer survivors in this study developed disturbed sleep as a result of cancer diagnosis and their sleep disruption was exacerbated by active cancer treatment. Insomnia also had a significant impact upon quality of life and these effects persisted long beyond the cessation of active anti‐cancer therapy. Early identification of insomnia symptoms in cancer care settings must be a priority to ensure that sleep disturbance is not overlooked or poorly managed. Copyright © 2010 John Wiley & Sons, Ltd.
Agents of support: psychometric properties of the Cancer Perceived Agents of Social Support (CPASS) questionnaire
Authors: Goldzweig Gil , Hasson‐Ohayon Ilanit , Meirovitz Amichay , Braun Michal , Hubert Ayala , Baider Lea 
Published: December 2009

AbstractObjective: The current study presents the development and the evaluation of the psychometric properties of the Cancer Perceived Agents of Social Support (CPASS). The CPASS is a new self‐rating instrument devised in order to enable both cancer patients and their spouses to report on the level of perceived social support they get. The CPASS evaluates the support given by different agents of support (spouse, family, friends and spiritual or religious beliefs) in several dimensions (emotional, cognitive and instrumental).Methods: The study sample comprised 662 cancer patients and their spouses recruited during a routine medical evaluation from three major cancer centers in Israel. The participants completed the CPASS and two other standardized instruments: The ENRICH Marital Satisfaction Scale (EMS) and the Brief Symptom Inventory (BSI).Results: Principal component analysis confirmed a three‐factor structure based upon the agent of support (spouse; friends/family; spiritual/religious beliefs). Cronbach's α coefficients for the agent of support indexes were high (0.80–0.95), while Cronbach's α levels for the kind of support were lower (0.45–0.72). Smallest Space Analysis (SSA) also confirmed the theoretical structure of the CPASS. Pearson correlation coefficients to the other study variables were high and significant.Conclusions: As a whole, the CPASS was found to be a valid tool for the current Israeli sample. Theoretical and practical conclusions and socio‐cultural implications are discussed. Copyright © 2009 John Wiley & Sons, Ltd.
Field evaluation of vaporised ethyl formate and carbon dioxide for fumigation of stored wheat
Authors: Dojchinov Greg , Damcevski Katherine A , Woodman James D , Haritos Victoria S 
Published: December 2009

AbstractBACKGROUND: Vapormate™ is a cylinderised non‐flammable mixture of ethyl formate (16.7% by weight) and carbon dioxide (CO2) that has been developed as a rapid fumigant of stored grain. Four field trials were undertaken on wheat in 50 t farm silos to demonstrate the feasibility of dynamic application. To assess treatment efficacy, each trial tested mixed stages of Rhyzopertha dominica F. (>11 000), Tribolium castaneum (Herbst.) (>1500) and Sitophilus oryzae (L.) (>13 000) in mesh cages positioned through the centre of the grain bulk and on the grain surface. Ethyl formate and CO2 concentrations were measured in the silo during fumigation and in ambient air outside the 6 m fumigation zone. Application rates of 420, 660 and 940 g m−3 of ethyl formate/CO2 formulation and exposure times of 24, 3 and 72 h, respectively, were examined using wheat of 10.4–11.7% moisture content and grain temperatures between 2 and 32 °C.RESULTS: All life stages of R. dominica and T. castaneum were fully controlled under all conditions tested, and mortality of all life stages of S. oryzae was greater than 98%.CONCLUSION: Dynamic application of vaporised ethyl formate and CO2 to 50 t silos proved safe to operators and rapidly effective against stored‐grain insects on cold to warm grain. Copyright © 2009 CSIRO, Australia. Published by John Wiley & Sons, Ltd
HREELS study of graphene formed on hexagonal silicon carbide
Authors: Koch R. J. , Haensel T. , Ahmed S. I.‐U. , Seyller Th. , Schaefer J. A. 
Published: December 2009

AbstractUsing high resolution electron energy loss spectroscopy (HREELS) in conjunction with low energy electron diffraction (LEED) and X‐ray induced photoelectron spectroscopy (XPS), we have studied surface reconstructions from Si‐rich to C‐rich surfaces up to graphene formation. It is shown that the coupling between the longitudinal optical phonons and the carrier plasmons that originate from the presence of the layered semimetallic character of graphene and few layer graphene (FLG) drastically influence the HREELS‐spectra. For the hydrogen smoothened SiC‐samples, which have been subsequently annealed under high Ar‐pressure [1], the Fuchs‐Kliewer surface phonon ω0 is completely screened and two other losses ω‐ and ω+, called plasmarons, appear. They originate from the coupling between surface optical phonons and plasma oscillations of free‐electrons resulting from the graphene/SiC interface. For the heated SiC‐samples under ultra‐high‐vacuum (UHV) conditions, the situation is different, which indicates cluster formation of graphene / graphite at the surface. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Charge transient spectroscopy measurements of metal‐oxide‐semiconductor
Authors: Arnold Markus , Fechner Axel , Zahn Dietrich R. T. 
Published: December 2009

AbstractCharge transient spectroscopy (QTS) is an electrical measurement technique related to deep‐level transient spectroscopy (DLTS). Using QTS it is possible to measure fast charge reloading processes even in the absence of depletion regions as a function of time and temperature with different pulse voltages and pulse widths. As a result, one can determine the number, the energetic position, the capture cross section, and the density of the electrically active traps.Here QTS measurements of Al/SiO2/Si Metal‐OxideSemiconductor structures are presented revealing the influence of manganese implantation into p‐ and n‐doped silicon on the charge carrier transport and trapping properties. The QTS results are compared to I‐V, C‐V and DLTS measurements on the same samples and the differences are discussed (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Formation of an interface layer between Al1‐xSixOy thin films and the Si substrate during rapid thermal annealing
Authors: Michałowski Paweł Piotr , Beyer Volkhard , Czernohorsky Malte , Kücher Peter , Teichert Steffen , Jaschke Gert , Möller Wolfhard 
Published: December 2009

AbstractSilicon diffusion from the substrate through Al1‐xSixOy thin films was investigated by ToF‐SIMS depth profiling. Two types of substrate stacks were analyzed: Si wafer with either native oxide or with additional silicon nitride layer. The amount of diffused silicon depends strongly on the type of the substrate. The activation energy for pure alumina was found to be 2.27 ± 0.02 eV and 3.73 ± 0.02 eV for SiO2/Si and Si3N4/SiO2/Si samples, respectively.Furthermore it was proved that the activation energy increases with higher concentration of Si for SiO2/Si samples whereas it decreases for Si3N4/SiO2/Si. Detailed analysis of SIMS depth profiles provide satisfactory explanation of this phenomenon: SiO2 has much stronger tendency to react with Al1‐xSixOy material forming an interface layer that restrain further diffusion of Si from the substrate (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantum transport in narrow‐gap semiconductor nanocolumns
Authors: Lüth H. , Blömers Ch. , Richter Th. , Wensorra J. , Estevez Hernandez S. , Petersen G. , Lepsa M. , Schäpers Th. , Marso M. , Indlekofer M. , Calarco R. , Demarina N. , Grützmacher D. 
Published: December 2009

AbstractInN nanowires were grown by plasma‐assisted MBE in a bottom‐up approach, while InAs nanocolumns were prepared top‐down by electron beam lithography. Both types of narrow‐gap semiconductor nanocolumns exhibit a surface accumulation with a cylinder‐like 2 DEG as conduction channel. In magnetoconductance measurements at low temperatures with the magnetic field parallel to the column axis the InN wires exhibit magnetoconductance oscillations with a repetition period of a magnetic flux quantum ϕ0. For the InAs columns the observed magnetoconductance oscillations have a period of half the flux quantum ϕ0/2. The interpretation is based on the different surface perfectness of both types of columns. The InN wires with an almost perfect crystallinity allow transport through coherent angular momentum states within the surface 2 DEG which yields a ϕ0 periodicity. The InAs column surfaces exhibit a high amount of surface defects arising from the preparation and only diffusive, phase conserving transport through the 2 DEG is possible, which allows Al'tshuler‐Aronov‐Spivak interferences with a period ϕ0/2. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
UV transparent single‐crystalline bulk AlN substrates
Authors: Bickermann Matthias , Epelbaum Boris M. , Filip Octavian , Heimann Paul , Nagata Shunro , Winnacker Albrecht 
Published: December 2009

AbstractBulk aluminum nitride (AlN) is a very promising substrate material for UV optoelectronics, and its UV transparency is of high interest for UV devices designed to emit through the substrate. We report on 500 μm thick bulk AlN substrates with plain UV transmittance exceeding 50% (i.e., absorption coefficients below 14 cm–1) for wavelengths from 220 nm to 380 nm in the main wafer area. Comparing the spectra of different AlN bulk samples, four major below band‐gap absorption bands are identified and interpreted based on a point defect model for AlN crystals. We conclude that a further reduction of oxygen contamination of the source material led to a significant decrease of UV absorption in both colorless and yellowish areas of those substrates. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Built‐in fields in non‐polar InxGa1–xN quantum dots
Authors: Schulz Stefan , O'Reilly Eoin P. 
Published: December 2009

AbstractWe present a detailed analysis of the internal built‐in potential in polar and non‐polar Inx Ga1–x N quantum dots (QDs). The applied model is based on a surface integral method to calculate the three‐dimensional electrostatic built‐in potential in semiconductor QDs of arbitrary shape. This technique allows for a detailed and systematic analysis of the different contributions to the total built‐in field. Here, we also investigate the impact of the QD geometry on the built‐in potential in structures grown along non‐polar directions of the crystal.Since there is uncertainty in the literature as to the sign of the piezoelectric constant e15 associated with the shear strain, we study the influence of this constant in detail. While recent results on non‐polar GaN/AlN QDs indicate that only a negative e15 leads to significant reduction in the built‐in field, we show that for InN/GaN QDs there should still be a significant field present, independent of the sign of the piezoelectric constant e15. However, this field is strongly reduced with increasing Ga concentration in the nanostructure. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of gas flow rates on the formation of III‐nitride nanowires
Authors: Chen Liang‐Yih , Liao Cheng‐I , Peng Hsuan‐Ying 
Published: December 2009

AbstractThis study achieved catalytic growth of gallium nitride nanowires (GaN‐NWs) and indium gallium nitride nanowires (InxGa1‐xN‐NWs) by the horizontal furnace chemical vapour deposition (HF‐CVD) method at the temperature of 900 °C and 550 °C, respectively. The morphologies and structures of III‐nitride nanowires depended on the gas flow rates were studied. Comparing the growth mechanisms of GaN‐NWs and InxGa1‐xN‐NWs, the vapour‐solid (VS) mechanism is dominant in GaN nanowires, except with a low ammonium flow rate, and the vapour‐liquid‐solid (VLS) mechanism is dominant in InxGa1‐xN nanowires. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Resonant MEMS based on cubic GaN layers
Authors: Niebelschütz F. , Brueckner K. , Jatal W. , Tschumak E. , As D. J. , Hein M. A. , Pezoldt J. 
Published: December 2009

AbstractIn this work, we report the fabrication of GaN microelectromechanical structures (MEMS) based on cubic GaN grown by molecular beam epitaxy on 3C‐SiC(100)/Si(100) pseudosubstrates. Free‐standing beam resonators with a width of 5 μm and lengths from 250 to 1000 μm were patterned and characterized. Magnetomotively and electrostatically actuated resonators were analyzed under ambient and vacuum conditions resulting in quality factors of up to 250 under ambient conditions up to 40.000 under vacuum (1.9x10‐5 mbar) and resonant frequencies from 97 to 406 kHz for the fundamental resonant mode. These results allow for the determination of the Young's modulus and the residual strain of the free standing structures. The measured GaN resonators exhibited Young's moduli from 235 to 260 GPa and high residual axial strains from 1.0x10‐3 to 1.25x10‐3. For the cubic GaN layers from which the resonators were fabricated, residual strains between 3.3x10‐3 and 5.8x10‐3 have been extracted from XRD measurements. These values are on the same order of magnitude but a definite factor higher compared to the measurement results obtained for the fabricated GaN‐beams, which indicates a partial layer relaxation caused by the influences of the MEMS fabrication processes. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Non‐polar cubic AlGaN/GaN HFETs grown by MBE on Ar+ implanted 3C‐SiC (001)
Authors: Tschumak Elena , Lindner J. K. N. , Bürger M. , Lischka K. , Nagasawa H. , Abe M. , As D. J. 
Published: December 2009

AbstractThe growth of cubic group III‐nitrides is a direct way to eliminate polarization effects, which inherently limit the fabrication of normally‐off heterojunction field‐effect transistors (HFETs) in GaN technology. HFET structures were fabricated of non‐polar cubic AlGaN/GaN hetero layers grown by plasma assisted molecular beam epitaxy (MBE) on free standing 3C‐SiC (001). The electrical insulation of 3C‐SiC was realised by Ar+ implantation before c‐AlGaN/GaN MBE. The structural properties of the epilayers were studied by high‐resolution x‐ray diffraction (HRXRD). HFETs with normally‐off and normally‐on characteristics were fabricated of cubic AlGaN/GaN. Capacitance‐voltage (CV) characteristics of the gate contact were performed to detect the electron channel at the c‐AlGaN/GaN hetero interface. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Factors affecting the luminescence emission of InGaN multi‐quantum wells grown on (0001) sapphire substrates by MOVPE
Authors: Martínez Oscar , Avella Manuel , Jiménez Juan , Bosi Matteo , Fornari Roberto 
Published: December 2009

AbstractThe luminescence emission of InGaN/GaN multi‐quantum wells (MQW) is affected by several factors, i.e. the composition, the QW thickness, the piezoelectric field and the high density of threading dislocations. In the case of heterostructures containing several QWs piled up, one has to consider the homogeneity of each QW and the thickness of the barrier layers between them, which have influence on the strain. We present herein a Cathodoluminescence (CL) study of a series of InGaN QW structures, paying special emphasis to the problem of the lateral distribution of In, and how it influences the emission properties of the QWs. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Novel InN/InGaN multiple quantum well structures for slow‐light generation at telecommunication wavelengths
Authors: Naranjo F. B. , Kandaswamy P. K. , Valdueza‐Felip S. , Lahourcade L. , Calvo V. , González‐Herráez M. , Martín‐López S. , Corredera P. , Monroy E. 
Published: December 2009

AbstractThe third order susceptibility is responsible for a variety of optical non‐linear phenomena ‐ like self focusing, phase conjugation and four‐wave mixing ‐ with applications in coherent control of optical communication. InN is particularly attractive due to its near‐IR bandgap and predicted high nonlinear effects. Moreover, the synthesis of InN nanostructures makes possible to taylor the absorption edge in the telecomunication spectral range and enhance nonlinear parameters thanks to carrier confinement. In this work, we assess the nonlinear optical behavior of InN/InxGa(1‐x)N (0.9 > x > 0.7) multiple‐quantum‐well (MQW) structures grown by plasma‐assisted MBE on GaN‐on‐sapphire templates. Low‐temperature (5 K) photoluminescence measurements show near‐IR emission whose intensity increases with the In content in the barriers, which is explained in terms of the existence of piezoelectric fields in the structures. The nonlinear optical absorption coefficient, α2, were measured at 1.55 μm using the Z‐scan method. We observe a strong dependence of the nonlinear absorption coefficient on the In content in the barriers. Saturable absorption is observed for the sample with x = 0.9, with α2 ∼ ‐9 x 103 cm/GW. For this sample, an optically controlled reduction of the speed of light by a factor S ∼ 80 is obtained at 1.55 μm (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)