bluuebunny/crossref_metadata_2025_split huggingface dataset:
The role of carbon in transport processes during PVT growth of bulk GaN
Authors: Rost H.‐J. , Siche D. , Gogova D. , Albrecht M. , Jacobs K. , Fornari R. 
Published: April 2009

AbstractThick GaN layers were deposited by the reaction of gallium with ammonia. The Physical Vapour Transport (PVT) process with NH3 addition is characterized by moderate NH3 flow rates, pressures, and consumption of reactants, by reduced parasitic growth and no NH4Cl formation. Carbon addition to the ammonia results in growth of thicker layers at increased transport rate and in single crystals even at Ga super saturations, which would normally be too high for single crystalline growth. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Narrow‐gap ferromagnetic semiconductors (In,Mn)Sb on GaAs (001): growth and properties
Authors: Tran Lien , Herfort Jens , Bierwagen Oliver , Hatami Fariba , Masselink W. Ted 
Published: April 2009

AbstractNarrow‐gap (In,Mn)Sb layers, which offer prospects for infrared spin‐photonics, were grown on GaAs (001) substrates using a Riber Compact 21T MBE system and a Veeco valved cracker cell for Sb. Samples consisting 0.4 μm (In,Mn)Sb/GaAs with different Mn content in the range of 1% were examined in this study in respect of their structural, magnetotransport and magnetization properties. It is found that Mn decreases the lattice constant as well as the degree of relaxation of (In,Mn)Sb films. The hole concentration increases with increasing Mn concentration resulting increased acceptor concentration and decreased resistivity.The magnetoresistance is found to be sensitive to the Mn concentration. The temperature‐dependent resistivity data at lower than 30 K show an increased resistivity with decreasing temperature, suggesting the insulating behavior of the samples. In addition, magnetization measurements reveal distinct hysteresis loops, indicating the ferromagnetic properties. The measured saturation magnetization values of the films are found to be dependent on Mn concentration. The Curie temperature is estimated to be below 50 K. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Biexcitonic photocurrent induced by two‐photon process at a telecommunication band
Authors: Kodera Tetsuo , Suzuki Ayako , Miyazawa Toshiyuki , Takagi Hiroyuki , Kumagai Naoto , Watanabe Katsuyuki , Nakaoka Toshihiro , Arakawa Yasuhiko 
Published: April 2009

AbstractWe report on photocurrent (PC) measurements of biexciton in a single self‐assembled InAs quantum dot (QD) at a telecommunication wavelength of 1.3 μm. We use shadow mask technique on an n‐i Schottky photodiode structure with QDs to excite a single QD resonantly. Coherent pulse excitation is realized in two types of setups utilizing (i) an optical parametric oscillator and (ii) a stable semiconductor laser diode. In both setups we observe the biexcitonic PC peaks induced by a coherent two‐photon process. Especially in the latter setups, the narrower pulse linewidth in energy provides a clearer biexcitonic PC peak because of reduced unwanted excitation. We estimate the binding energy ΔEB of our telecom‐band biexciton to be 0.9 meV from the splitting between excitonic and biexcitonic resonances. The result suggests our telecom‐band exciton‐biexciton system is a good candidate for the building block of fiber‐based controlled‐rotation quantum logic operation. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Heteroepitaxial growth of a rotated AlInSb layer mediated by an InSb bi‐layer on a Si(111) substrate
Authors: Saito Mitsufumi , Mori Masayuki , Ueda Koji , Maezawa Koichi 
Published: April 2009

AbstractTwo‐step growth of an AlInSb film mediated by an InSb bi‐layer on a Si(111) substrate was performed in a molecular beam epitaxy (MBE) chamber. The growth was observed by in situ reflection high energy electron diffraction. After the deposition, the samples were characterized by X‐ray diffraction (XRD). It is confirmed that the grown AlInSb films were rotated by 30° with respect to the Si substrates. The lattice mismatch between the AlInSb and the Si substrate was reduced by the rotation. Using this method, epitaxial AlyIn(1‐y)Sb layers which have the composition ratio y of 0.22‐0.65 can be achieved without thick buffer layers. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
C ‐plane chromia on c ‐plane sapphire
Authors: Tarre A. , Carlotti G. , Gerst A. , Mändar H. , Niilisk A. , Sammelselg V. , Socino G. , Rosental A. 
Published: April 2009

AbstractChromium oxide thin films were atomic layer deposited from CrO2Cl2 and CH3OH on α‐Al2O3(0 0 1) (c ‐sapphire) substrates at 420 °C. On the basis of X‐ray reflection evidence, the thickness of the films in a series prepared ranged from 4 to 400 nm. As it was ascertained by reflection high‐energy electron diffraction, the films grew epitaxially. Electron probe microanalysis showed that O/Cr atomic ratio in them was close to 1.5 and that the residual impurities were present in insignificant amounts. The rms roughness of the films measured by atomic‐force microscopy and X‐ray reflection was of the order of 1 nm or less. X‐ray diffraction and Raman scattering data suggested that the films were strained, and that the strain was tensile in the c direction and compressive in the c plane. According to the surface Brillouin scattering measurements, the elastic properties of the films differed only slightly from those for single‐crystal bulk chromia. The films, when surface activated with Pt nanoislands, had a moderate response to CO in air with the transition times in the range of tens of seconds. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Homoepitaxial growth and characterization of ZnO(0001) thin films grown by metalorganic chemical vapor epitaxy
Authors: Ive Tommy , Ben‐Yaacov Tammy , Van de Walle Chris G. , Mishra Umesh K. , Denbaars Steven P. , Speck James S. 
Published: April 2009

AbstractWe study the properties of Zn‐face ZnO(00.1) layers grown on the Zn‐face of high quality ZnO(00.1) single crystal wafers by metalorganic chemical vapour epitaxy. The layers are grown directly on the ZnO substrates without any treatment of the substrate before starting the growth. The growth temperature is varied between 600–1050 °C while the reactor pressure is kept at 50 Torr. Atomic force microscopy reveals monolayer steps with a step length of 170 nm. The root‐mean‐square roughness is 0.1 nm over a 20×20 μm2 area. A two‐dimensional step morphology is only seen for growth temperatures above 950 °C. Layers grown below 950 °C exhibit very rough three dimensional surface morphologies. The full width at half maximum for x‐ray rocking curves is 22 arcsec and 36 arcsec across the (00.2) and the (20.1) reflections, respectively. This is comparable to the rocking curve widths of the as‐received substrates. The peaks of the ZnO epitaxial thin film and the substrate are indistinguishable in reciprocal space maps. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
GaN and digital electronics: A way out of Moore's law?
Authors: Palacios Tomás , Chung Jinwook W. , Saadat Omair , Mieville Frederic 
Published: April 2009

AbstractAfter forty years following Moore's law, Si digital electronics is reaching its limits, both in performance and in economic viability. In this paper we describe how nitride semiconductors can be combined with Si electronics to allow electronics to move beyond Moore's law and to enable new functionality. Three different research areas will be discussed: high performance digital circuits, high temperature electronics and heterogeneous integration of nitride and Si electronics. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electroluminescence characterization of AlGaN/GaN HEMTs
Authors: Lossy Richard , Glowacki Arkadiusz , Boit Christian , Würfl Joachim 
Published: April 2009

AbstractMicroscopic electroluminescence (EL) measurements on AlGaN/GaN high‐electron‐mobility transistors are reported. Photon emission is detected from front side and also from the backside of the wafer. Using both detection geometries manufacturing related dependencies can beidentified. Investigation of EL from backside during pinch‐off operation reveals detailed emission pattern that are partially hidden during front side observation. Spectrally resolved photon emission shows different pattern for on‐state and off‐state condition. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electron transport properties in InAs four‐terminal ballistic junctions under weak magnetic fields
Authors: Koyama M. , Fujiwara K. , Amano N. , Maemoto T. , Sasa S. , Inoue M. 
Published: April 2009

AbstractWe report on the electron transport properties based on ballistic electrons under magnetic fields in four‐terminal ballistic junctions fabricated on an InAs/AlGaSb heterostructure. The four‐terminal junction structure is composed of two longitudinal stems with two narrow wires slanted with 30 degree from the perpendicular axis. The electron focusing peak was obtained with the bend resistance measurement. Then it was investigated the nonlinear electron transport property of potential difference between longitudinal stems due to ballistic electrons with applying direct current from narrow wires. Observed nonlinearity showed clear rectification effects which have negative polarity regardless of input voltage polarity. Although this nonlinearity was qualitatively changed due to the Lorentz force under magnetic fields, the degradation of ballistic effects on nonlinear properties were observed when the current increased to higher strength. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Multicarrier analysis of magnetotransport data at low and high electric fields
Authors: Murthy O. V. S. N. , Venkataraman V. 
Published: April 2009

AbstractWe present some results on multicarrier analysis of magnetotransport data. Both synthetic as well as data from narrow gap Hg0.8Cd0.2Te samples are used to demonstrate applicability of various algorithms vs. nonlinear least square fitting, Quantitative Mobility Spectrum Analysis (QMSA) and Maximum Entropy Mobility Spectrum Analysis (MEMSA). Comments are made from our experience on these algorithms, and, on the inversion procedure from experimental R/σ‐B to S‐μ specifically with least square fitting as an example. Amongst the conclusions drawn are: (i) Experimentally measured resistivity (Rxx, Rxy) should also be used instead of just the inverted conductivity (σxx, σxy) to fit data to semiclassical expressions for better fits especially at higher B. (ii) High magnetic field is necessary to extract low mobility carrier parameters. (iii) Provided the error in data is not large, better estimates to carrier parameters of remaining carrier species can be obtained at any stage by subtracting highest mobility carrier contribution to σ from the experimental data and fitting with the remaining carriers. (iv)Even in presence of high electric field, an approximate multicarrier expression can be used to guess the carrier mobilities and their variations before solving the full Boltzmann equation. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Differentiation induced byAchyrocline satureioides(Lam) infusion in PC12 cells
Authors: Blasina M. F. , Vaamonde L. , Morquio A. , Echeverry C. , Arredondo F. , Dajas F. 
Published: April 2009

AbstractEpidemiological studies have shown that flavonoid‐rich plants induce beneficial health effects that are likely beyond their potent antioxidant capacity. Thus, the mechanisms by whichAchyrocline satureioides(AS), a popular South American medicinal plant, protects cells and neurons in culture, are still unclear. In this sense, a recently described trophic capacity for flavonoids, similar to that evoked by growth factors, could be one of the mechanisms involved in AS cellular protection. Since this trophic activity causes differentiation of PC12 cells, the cell differentiation capacity of AS and some of its flavonoids were evaluated. PC12 cells were treated with AS infusion (10 or 20 µg/mL of total polyphenols), quercetin (Q) (12.5 or 25 µm), luteolin (L) (25 µm), Q + L (12.5 µm each one) or nerve growth factor (NGF) for 3 days. Four morphological parameters (percentage of cells with neurites longer than one cell body diameter, percentage of cells with neurites, average number of neurites per cell and percentage of fusiform cells) were explored. The AS infusion showed differentiation capacity on all parameters with similar potency when compared with NGF. Besides, AS was more potent than some of its constituent flavonoids: Q, L or their combination. Copyright © 2009 John Wiley & Sons, Ltd.
Designing a Combinatorial Library by Using Reagent Pharmacophore Fingerprint
Authors: Chen Hongming , Börjesson Ulf , Engkvist Ola , Kogej Thierry , Svensson Mats A. , Blomberg Niklas , Weigelt Dirk , Burrows Jeremy N. , Lange Tim 
Published: April 2009

AbstractA method is introduced for performing reagent selection for chemical library design based on topological (2D) pharmacophore fingerprints. Optimal reagent selection is achieved by optimizing the Shannon entropy of the 2D pharmacophore distribution for the reagent set. The method, termed ProSAR, is therefore expected to enumerate compounds that could serve as a good starting point for deriving a structure activity relationship (SAR) in combinatorial library design. This methodology is exemplified by library design examples where the active compounds were already known. The results show that most of the pharmacophores on the substituents for the active compounds are covered by the designed library. This strategy is further expanded to include product property profiles for aqueous solubility, hERG risk assessment etc. in the optimization process so that the reagent pharmacophore diversity and the product property profile are optimized simultaneously via a genetic algorithm. This strategy is applied to a two‐dimensional library design example and compared with libraries designed by a diversity based strategy which minimizes the average ensemble Tanimoto similarity. Our results show that by using the PSAR methodology, libraries can be designed with simultaneously good pharmacophore coverage and product property profile
Similarity‐Based Virtual Screening Using Bayesian Inference Network: Enhanced Search Using 2D Fingerprints and Multiple Reference Structures
Authors: Abdo Ammar , Salim Naomie 
Published: April 2009

AbstractIt has been known that different reference structure retrieve different sets of structures. Recent works in similarity searching have suggested that significant improvements in retrieval effectiveness can be achieved by combining results from different reference structures. One of an important characteristic of the Bayesian inference network (BIN) model is that permits the combining of multiple reference structures. In this paper we introduce a formal inference net model to directly combine the contributions of multiple reference structures, and propose a novel approach to the combination of information from various reference structures. The inference net model of similarity, which was designed from this point of view, treats similarity searching as an evidential reasoning process where multiple sources of evidence about target structure are combined to estimate similarity scores. In this paper, we have compared BIN with other similarity searching methods when multiple bioactive reference structures are available. Six different 2D fingerprints were used in combination with data fusion (DF) and nearest neighbor (NN) approaches as search tools and also as descriptors for BIN. Our empirical results show that the BIN consistently outperformed all conventional approaches such as DF and NN, regardless of the fingerprints that were tested. The superiority of BIN over conventional approaches is ascribed to the fact that BIN understands the content of the descriptors of the structures and references and used this understanding to infer the direct relationship between structures and references.
Computational study on the comparative synthesis of energetic FOX‐7 derivatives
Authors: Liu Min‐Hsien , Cheng Ken‐Fa , Chen Cheng , Hong Yaw‐Sun 
Published: April 2009

AbstractEthene and two kinds of nitrating reagents (HNO3 and N2O5) were included in respective molecular systems, which progressed through a two‐stage electrophilic and free radical nitrosubstitution, resulting in the corresponding nitroethene compounds. Subsequent halogenation (using Cl2 and Br2) and amination (using ammonia) were then performed, also by electrophilic and radical substitution, to produce the target 1,1‐diamino‐2,2‐dinitroethene (FOX‐7) derivatives. All transition state species were identified using a two‐ or three‐structure Synchronous Transit‐Guided Quasi‐Newton between the Cartesian coordinates of the related molecular systems at specific reaction stages. The modeling results suggest that N2O5 is the better agent for nitration and bromine is suitable for use in halogenation. The comparable activation energies throughout the reaction stages were considered to imply the most feasible pathways of FOX‐7 synthesis. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010
Electron localization and the second moment of the exchange hole
Authors: Ángyán J. G. 
Published: April 2009

AbstractThe localization tensor, which is a global measure of the itinerant character of the electrons, has been defined by Resta as the second cumulant moment of the position operator per electron. It seems to be a meaningful parameter not only for solids but also for finite molecular systems. In the independent‐particle limit, this quantity can be interpreted as the density‐weighted average of the second moment of the exchange hole. After examining several possible local measures based on the moment analysis of the exchange hole, it turns out that the density weighted squared exchange hole dipole moment might be a useful local indicator of electron localization. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
The effectiveness of producer‐side machine‐independent optimizations for mobile code
Authors: Amme Wolfram , von Ronne Jeffery , Adler Philipp , Franz Michael 
Published: April 2009

AbstractPortable mobile code is often executed by a host virtual machine using just‐in‐time compilation. In this context, the compilation time in the host virtual machine is critical. This compilation time can be reduced if optimizations are performed ahead‐of‐time before distribution of the mobile code. Unfortunately, the portable nature of mobile code limits ahead‐of‐time optimizations to those that are machine‐independent. This work examines the effect of machine‐independent optimizations on the performance of mobile code applications. All experiments use the SafeTSA Format, a mobile code format that is based on Static Single Assignment Form (SSA Form). The experiments, which are performed on both the PowerPC and IA32 architectures, indicate that the effects of performing classical machine‐independent optimizations are—in fact—quite machine‐dependent. Nevertheless, the results demonstrate that applying such optimizations in a mobile code system can be beneficial. Copyright © 2009 John Wiley & Sons, Ltd.
Adaptive networks as second order governance systems
Authors: Nooteboom Sibout , Marks Peter 
Published: April 2009

AbstractWe connect the idea of ‘levers for change’ with ‘governance capacity’ and propose ‘adaptive networks’ as an ideal type embedded in, and leveraging change in, governance systems. Discourses connect practices of citizens and companies with that governance system. Aware of interdependencies, individuals may act in the interest of the whole system and self‐organize into adaptive networks, and influence discourses to a common end. Their effectiveness depends on second‐orderedness: adaptive networks in niches outside the governance system may influence it through levers. The motivation and competence to build creative tension helps adaptive networks emerge and coevolve with power networks, improving governance capacity. Copyright © 2009 John Wiley & Sons, Ltd.
Epistemic communities and the global alliance against tobacco marketing
Authors: Mukherjee Amit , Ekanayake E. M. 
Published: April 2009

AbstractThe World Health Organization's (WHO's) Framework Convention on Tobacco Control (FCTC) is a major blow to the worldwide expansion strategies and marketing practices of transnational tobacco companies. As expected, the industry vehemently opposed the treaty, lobbying instead for voluntary agreements and regulation by the market. However, in spite of bitter and persistent opposition by the tobacco industry, the FCTC was adopted by WHO. If the tobacco industry “lost” its battle to prevent FCTC from being institutionalized, who “won” and how? Our research suggests that the efforts of the epistemic community—a like‐minded network of professionals whose authoritative claim to consensual knowledge provides them with a unique source of power in public policy decision making—won the battle by being able to better convince the decision makers as to the needs of the FCTC by relying on, and successfully disseminating, its knowledge, expertise, and ideas. © 2009 Wiley Periodicals, Inc.
Crisis management—dealing with asymmetric information problems
Authors: Chong Beng Soon , Lee Chay Hoon 
Published: April 2009

AbstractA key component of crisis management involves the management of asymmetric information problems. Drawing on the experience of the recent severe acute respiratory syndrome (SARS) epidemic, this article examines the nature of the asymmetric information problems that typically prevail during a crisis, the costs associated with it, and the various mechanisms to address the problems. We find that the asymmetric information problems in the event of a crisis can be severe and potentially costly if the problems are not adequately resolved. © 2009 Wiley Periodicals, Inc.
Examining differences in competitive intelligence practice: China, Japan, and the West
Authors: Fleisher Craig S. , Wright Sheila 
Published: April 2009

AbstractThis article identifies the state of competitive intelligence (CI) in Asia—specifically, two of its most prominent economic powers, China and Japan. Comparisons with Western, mainly U.S. practice, are made, particularly where data and management research from those countries supports this approach. In terms of current practice, CI in Japan is more developed than in China, although China continues to devote increasing attention and resources to the area. Decision makers in multinational companies, competing in China or Japan, or with firms that originate there, should be aware of the competitive implications emanating from their utilization of CI. © 2009 Wiley Periodicals, Inc.
A comparison of FDI determinants in China and India
Authors: Zheng Ping 
Published: April 2009

AbstractThis study explores foreign direct investment (FDI) determinants in China and India and fills the gap in the literature by providing a comprehensive empirical comparison analysis. Two panel data sets and two statistical models are employed to identify the determinants of FDI inflows from home countries worldwide to the two host countries by considering both home and host countries' characteristics. The empirical results show some interesting similarities and differences between the two countries. Market growth, imports, labor costs, and country political risk/policy liberalization are the determinants for both countries. However, exports, market size, and borrowing costs are important to China's FDI, while geographical and cultural distance factors are important to India's FDI. © 2009 Wiley Periodicals, Inc.