bluuebunny/crossref_metadata_2025 huggingface dataset:
Calculation of the Raman frequency and the damping constant of a coupled mode in the ferroelectric and paraelectric phases in KH2PO4
Authors: Karacali H. , Kiraci A. , Yurtseven H.
Published: January 2010

The Raman frequency of the coupled mode $\omega _ - $ associated with the order parameter is calculated as a function of pressure from the mean field theory in the ferroelecric phase of KDP. Using the frequencies of the coupled mode, the pressure dependence of the damping constant $\Gamma _ - $ is calculated by the proton spin lattice relaxation time and by the energy fluctuation of this mode of KDP in the ferroelectric (FE) phase. For the paraelectric (PE) phase, the Raman frequency of the coupled mode $\omega _ - $ is calculated as a function of temperature at 6.54 kbar. The temperature dependence of the damping constant $\Gamma _ - $ is performed only by the energy fluctuation of the coupled mode $\omega _ - $ in the PE phase of KDP. The values of the activation energy U are extracted from the pressure and temperature dependence of the damping constant $\Gamma _ - $ of this coupled mode $\omega _ - $ for both FE and PE phases of KDP.
Role of bathocuproine as hole‐blocking and electron‐transporting layer in organic light emitting devices
Authors: Tomova Reni , Petrova Petia , Stoycheva‐Topalova Rumiana
Published: January 2010

In this paper we present our results concerning the role of 2,9‐Dimethyl‐4,7‐diphenyl‐1,10‐phenanthroline (bathocuproine, BCP) in OLED structures with emissive layer of Tris‐(8‐hydroxyquinoline) aluminum (Alq3). It is established that instead of the higher working voltage of devices with bathocuproine their current efficiency significantly increased. This higher efficiency indicates strong hole‐blocking nature of bathocuproine (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Catalytic activity of gold on nanocrystalline diamond support
Authors: Veres Miklós , Perevedentseva Elena , Karmenyan Artashes V. , Tóth Sára , Koós Margit
Published: January 2010

A simple and easily realizable method was found for the preparation of supported Au catalyst by sputtering island type gold film onto nanocrystalline diamond particles, that can catalyse CO oxidation to CO2. The oxidation of CO molecules from ambient air was observed and investigated by spectroscopic methods. Characteristic CO peaks of molecules adsorbed on gold surface and an increased intensity of the CO2 bands were detected, indicating the catalyst effect of the Au film. The catalytic efficiency was found to be dependent on the morphology of the deposited gold layer. Our measurements indicate also that CO molecules could adsorb permanently on active Au sites, leading to lowered activity of the catalyst. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Employing the effective medium approximation to model the optical properties of crystallized a‐Si:H obtained by MIC
Authors: Muller T. F. G. , Knoesen D. , Arendse C. J. , Halindintwali S. , Malgas G. F. , Houweling Z. S. , Schropp R. E. I.
Published: January 2010

Metal induced crystallization of hydrogenated amorphous silicon has been the subject of intense scrutiny in recent years. In this contribution we report on the metal‐mediated‐thermally induced changes of the structural and optical properties of hydrogenated amorphous silicon deposited by hot‐wire CVD, where aluminium and nickel were used to induce crystallization. The metal‐coated amorphous silicon was subjected to a thermal annealing regime of between 150 and 520°C. The structural measurements, obtained by Raman spectroscopy, show partial crystallization occurring at 350 °C. At the higher annealing temperatures of 450°C and 520°C complete crystallization occurs. Reflection and transmission measurements in the UV‐visible range were then used to extract the optical properties. By adopting the effective medium approximation a single optical model could be constructed that could successfully model material that was in different structural phases, irrespective of metal contamination. Changes in the absorption of the material in various stages of transition were confirmed with a directly measured absorption technique, and the modelled absorption closely followed the same trends. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Excitation power dependent photolu‐ minescence of PECVD a‐SiOx:H (x<2) thin films
Authors: Bacıoğlu Akın , Kodolbaş Alp Osman , Öktü Özcan
Published: January 2010

The excitation power dependent visible photoluminescence (PL) property of an a‐SiOx:H (x < 2) sample prepared in a PECVD system is studied within a temperature range of 12 K and 400 K. An explicit PL band was observed at the photon energy of 2.1 eV. It was observed that the PL intensity increased with a power of the excitation intensity (IPL∝Lγ) changed between 1.3 mWcm‐2 and 25 mWcm‐2. γ was calculated to change between 0.8‐1.2 depending on the measurement temperature. The 2.1 eV PL band was found to show weak thermal activation energy around room temperature and calculated as about 1meV. The temperature dependence of PL for each excitation power was fitted to a function proposed due to the thermal activated radiative recombination and the defect related non‐radiative recombination mechanism. As a result of the model the ratio of the average distance between a carrier and the non‐radiative defect center to the decay length of the wave function of the defect was calculated to be varying between 21 and 33 with increased generation rate range of 1.75x1016 cm‐3/s‐3.5x1017 cm‐3/s. The results were discussed in terms of the separation of phases and the behavior of thermally activated incoherent hopping migration of electrons to combine with self trapped holes (STH) to form self trapped excitons (STE). (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On nanoheteromorphous structure in amorphous As2S3 films prepared by different methods
Authors: Sarsembinov Sh. Sh. , Prikhodko O. Yu. , Ryaguzov A. P. , Maksimova S. Ya. , Daineko E. A. , Iskakov R. M. , Ushanov V. Zh.
Published: January 2010

By the method of Raman spectroscopy as well as the methods of thermo‐gravimetric and differentially‐thermal analyses the structure of amorphous As2S3 films prepared by thermal evaporation in a vacuum and by radio frequency ion‐plasma sputtering has been studied. The techniques are strongly differing in the conditions of substance vaporization and condensation of atoms on a substrate. It was shown that the concept of nanoheteromorphism can be used to the description of these amorphous films structure. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrical and structural properties of p ‐type nanocrystalline silicon grown by LEPECVD for photovoltaic applications
Authors: Micard Gabriel , Hahn Giso , Terheiden Barbara , Chrastina Daniel , Isella Giovanni , Moiseev Tamara , Cavalcoli Daniela , Cavallini Anna , Binetti Simona , Acciarri Maurizio , Le Donne Alessia , Texier Michael , Pichaud Bernard
Published: January 2010

p‐doped hydrogenated nanocrystalline silicon (p‐nc‐Si:H) is one of the most critical layers in thin film silicon solar cells. LEPECVD is a new technique for the growth of nc‐Si at high growth rate without compromising the layer quality, using a dense but low energy plasma. Thin p‐nc‐Si:H layers are grown on glass and ZnO:Al coated glass and their structural and electrical properties are investigated as a function of the silane dilution (d) and of the doping ratio (DR). The influence of the substrate on the structural properties is investigated and discussed. The incubation layer is clearly observed on both substrate types and its thickness is estimated. LEPECVD distinguishes itself from other high growth rate methods by a very low impurity distribution coefficient to obtain a comparable conductivity and boron density. The conduction path is shown to be dependent on the density of boron in the layer while a significant decrease of conductivity at high DR is not observed in the studied range (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of selenization pressure on the growth of Cu2ZnSnSe4 films from stacked metallic layers
Authors: Salomé P. M. P. , Fernandes P. A. , Cunha A. F. da
Published: January 2010

Cu2ZnSnSe4 (CZTSe) is a p‐type semiconductor with a high absorption coefficient, 104 to 105 cm‐1, and is being seen as a possible replacement for Cu(In,Ga)Se2 in thin film solar cells. Yet, there are some fundamental properties of CZTSe that are not well known, one of them is its band gap. In order to resolve its correct value it is necessary to improve the growth conditions to ensure that single phase crystalline thin films are obtained. One of the problems encountered when growing CZTSe is the loss of Sn through evaporation of SnSe. Stoichiometric films are then difficult to obtain and usually there are other phases present. One possible way to overcome this problem is to increase the pressure of growth of CZTSe. This can be done by introducing an atmosphere of an inert gas like Ar or N2. In this work we report the results of morphological, structural and optical studies of the properties of CZTSe thin films grown by selenization of DC magnetron sputtered metallic layers under different Ar pressures. The films are analysed by SEM/EDS, Raman scattering and XRD. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Annealing studies of substoichiometric amorphous SiOx layers for c‐Si surface passivation
Authors: Einsele F. , Beyer W. , Rau U.
Published: January 2010

We investigate thermal stability of amorphous substoichiometric silicon‐oxide alloys with oxygen concentrations from 0 to 10 at‐%. Annealing experiments, including effective lifetime measurements, hydrogen effusion, and infrared absorption spectroscopy, yield a surface passivation on p‐type float‐zone crystalline silicon wafers with maximum effective lifetimes up to 1.5 ms. The thermal stability of the passivation increases with increasing oxygen concentration of the films. For oxygen concentrations above 5%, we observe a decrease of passivation due to the formation of voids in the material, which shows in a low temperature peak of the H effusion spectra. Annealing leads to a structural transition of the material which is accompanied by an increase in effective lifetime. The stretching mode absorptions of Si– O–Si molecular vibrations near 1000 cm–1 shift towards higher wavenumbers, both with increased oxygen concentration and upon annealing of the films. For increased oxygen concentrations, the Si–H stretching modes shift from predominantly 2000 cm–1 to 2090 cm–1(© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Serializing C intermediate representations for efficient and portable parsing
Authors: Meister Jeffrey A. , Foster Jeffrey S. , Hicks Michael
Published: January 2010

C static analysis tools often use intermediate representations (IRs) that organize program data in a simple, well‐structured manner. However, the C parsers that create IRs are slow, and because they are difficult to write, only a few implementations exist, limiting the languages in which a C static analysis can be written. To solve these problems, we investigate two language‐independent, on‐disk representations of C IRs: one using XML and the other using an Internet standard binary encoding called eXternal Data Representation (XDR). We benchmark the parsing speeds of both options, finding the XML to be about a factor of 2 slower than parsing C and the XDR over 6 times faster. Furthermore, we show that the XML files are far too large at 19 times the size of C source code, whereas XDR is only 2.2 times the C size. We also demonstrate the portability of our XDR system by presenting a C source code querying tool in Ruby. Our solution and the insights we gained from building it will be useful to analysis authors and other clients of C IRs. We have made our software freely available for download at http://www.cs.umd.edu/projects/PL/scil/. Copyright © 2010 John Wiley&Sons, Ltd.
Reactivity and Conversion Behaviour of Brazilian and Imported Coals, Charcoal and Blends in view of their Injection into Blast Furnaces
Authors: Machado J. G. M. S. , Osório E. , Vilela A. C. F. , Babich A. , Senk D. , Gudenau H. W.
Published: January 2010

For about 10 years the steel industry in Brazil has been using pulverized coal injection (PCI) technology in blast furnaces based on imported coals. In order to decrease the dependence on imported coals, Brazilian coal which has limited use due to high ash content is suggested to be mixed with imported coal and charcoal. The aim of this study is to examine the reactivity and combustion behaviour of the mentioned materials. The use of charcoal in the Brazilian steel industry reduces the CO2 emissions, since it represents a renewable source of carbon. The reactivity of the coal, charcoal and mixtures is evaluated through TGA. To provide a useful insight into the practice of PCI in blast furnaces, experiments are carried out with a laboratory rig at RWTH Aachen University that simulates the behaviour of fines injected into the raceway. The results of this study are presented and discussed.
Numerical Analysis of Stake Mark Induced Failure of a Rotor Shaft
Authors: Bambach M. , Al‐Baouni M. , Kilpatrick N. , Soto S. , Kretschmer M. , Hirt G.
Published: January 2010

In this paper, the stake mark induced failure of a generator rotor forging is analysed using finite element analyses in combination with a Cockroft & Latham failure model. Evidence is found from damage analysis that the rotor failed due to micro cracks and residual stresses induced by a double stake mark, which was located at a position subject to concentrated rotating‐bending stress amplitudes and torsional mean stress. The analysis presented here verifies the results of the damage analysis by showing that the stake mark configuration of the failed rotor was the most detrimental among a number of similar configurations. According to the finite element analysis, this stake mark configuration combines a high probability of inducing propagating sub‐surface micro‐cracks with considerable tensile residual stresses.
Model for Microstructure Prediction in Hot Strip Rolled Steels
Authors: dos Santos A. A. , Barbosa R.
Published: January 2010

Phase transformations from work‐hardened austenite after hot rolling of steel are of paramount importance for achieving the required mechanical properties. Moreover, it influences the control of cooling process in the cooling table. This paper proposes semi‐empirical mathematical models for predicting such transformations in carbon‐manganese and microalloyed steels, subjected to transformations conditions leading to a microstructure constituted by ferrite and pearlite. To develop the models, dilatometric tests were carried out in a Gleeble 3500 machine, simulating the industrial processing conditions as close as possible, including the effect of coiling. Emphasis was placed on the application of a criterion for determining the start of pearlite formation, which was based on carbon enrichment of austenite during the ferrite formation. Based on comparisons between measured and calculated ferrite fractions in tested specimens, it was proposed to consider a transition of the thermodynamic conditions prevailing during ferrite formation, which depend on steel chemistry and transformation conditions. As a preliminary assessment of its predictability the model was applied to a typical industrial process condition for microalloyed steels in hot strip rolling. It was shown that the model was capable of predicting reasonably well the evolution of ferrite and pearlite during the cooling in and also during the subsequent coiling process.
Friction and Temperature Development in the Hot Roll Cladding Process
Authors: Bach Fr.‐W. , Bormann D. , Rodmann M. , von Senden genannt Haverkamp H.
Published: January 2010

The setting of the optimum process parameters for high‐quality roll‐cladded composites requires detailed knowledge of their effects on adhesion and formability. This being the case, it is the objective of this paper to qualify and quantify both the thermal processes and the friction in the roller gap. The objective was worked out in three steps: the first step was to determine the friction with the aid of the forward‐slip procedure. In this case, the process parameters of temperature, rolling speed und degree of formability are of particular interest. In the second step, and by means of these process parameters, the friction coefficients were evaluated and modelled using the methods of statistical trials planning. In the third step, thermographic images were taken in the roller gap. This determined in particular the effect of degree of formability and rolling speed on the heat development.
A Study on the Effect of Na2O on the Viscosity for Ironmaking Slags
Authors: Kim H. , Kim W. H. , Park J. H. , Min D. J.
Published: January 2010

The viscosities of CaO‐SiO2‐10wt%MgO‐20wt%Al2O3‐Na2O slags (CaO/SiO2 = 0.8–1.2, wt%Na2O = 0–10) were measured to estimate the effect of Na2O on the viscous behavior at elevated temperatures. The slag viscosity at 1773 K decreased with increasing Na2O contents, which is observed in a basic oxide component. However, the FT‐IR spectroscopic analysis of the slag structure seemed to verify that [AlO4]‐tetrahedra depolymerized more readily than [SiO4]‐tetrahedra due to ionic charge compensation which has a tendency to be more effective on [AlO4]‐tetrahedra. Hence, for the present slag system, the viscosity decreased with additions of Na2O by providing network breaking O2‐ ions, and the charge balance by Na+ ions independently contributed to the depolymerization of the network structure of the molten slag. In addition, Na2O also lowered the critical temperature (TCR) resulting in a larger temperature difference between the operating temperature (TOP) and TCR, which can enhance operational stability.
Healing Men and Community: Predictors of Outcome in a Men's Initiatory and Support Organization
Authors: Burke Christopher K. , Maton Kenneth I. , Mankowski Eric S. , Anderson Clinton
Published: January 2010

Men have poorer health and declining social outcomes when compared to women, and research suggests that behaviors related to restrictive and traditional male gender roles contribute to this disparity. This study is an examination of The ManKind Project International (MKPI), a community‐based organization that provides alternative male gender norms and a community support system to help reinforce them. The MKPI runs an intensive, experiential “Training Adventure Weekend” (TAW), followed by voluntary, on‐going peer‐led support and integration groups (I‐Groups). One hundred men completed a pre‐TAW questionnaire, an interview, and a long‐term follow‐up (>18 mo.) questionnaire. The study examined if there was change on the primary study variables at follow‐up, and the relationship of background characteristics (age, self‐help group experience) and factors related to participation (MKPI beliefs, social support, I‐Group participation) to the criterion variables (depression symptoms, gender role conflict, and life satisfaction) at follow‐up. Results indicated significant change in the expected directions on the primary study variables, suggesting that for these men, participation has a positive impact. Most importantly, changes in MKPI‐related beliefs and social support significantly predicted positive outcomes. Also, more positive outcomes were found among men 30–44 years of age, but not among those with more prior self‐help experience or I‐Group participation. Possible explanations for these findings and directions for further research are discussed.
Applied Roles and the Future of Community Psychology
Authors: Jenkins Richard A.
Published: January 2010

The roles for community psychologists have changed over the past several decades. These changes have implications for training, traditional academic roles, and the capacity of the field to maintain its integrity and further development. Changes in the scope of community psychology as a field as well as the roles of community psychologists are described with consideration of how they may affect participation in the field, retention of membership in SCRA, and potential directions for training.
Effect of Sodium Salicylate on the Properties of Gemini Surfactant Solutions
Authors: Ye Zhongbin , Han Lijuan , Chen Hong , Shi Leiting , Luo Pingya
Published: January 2010

In this paper, the effect of sodium salicylate on the solution properties of a gemini surfactant, butylidene‐α, ω‐bis (cetyl dimethyl ammonium bromide), was investigated through absorbance and dynamic light scattering (DLS) measurement, transmission electron microscope (TEM) observation, and rheology measurement. The DLS experiment showed that the average size of aggregates increases with the addition of sodium salicylate. The TEM experiment showed that the addition of sodium salicylate causes the change of the size and shape of aggregate. With the increase of the concentration of sodium salicylate, the viscosity of the gemini surfactant solution reaches a maximum value and the flow pattern of the gemini surfactant solution also undergoes a great change with a transition from a Newtonian fluid to a non‐Newtonian fluid.
Interaction of Azo Dye with Cationic Surfactant Under Different pH Conditions
Authors: Nazar Muhammad Faizan , Shah Syed Sakhawat , Khosa Muhammad Arshad
Published: January 2010

The aggregation induced by Alizarin Yellow R (AYR) in the cationic surfactant, cetyltrimethylammonium bromide (CTAB), was investigated by measuring their UV–visible absorption spectra. Conductance measurements as a function of surfactant concentration below and above the critical micelle concentration (CMC) were studied. CTAB aggregation takes place at the concentration far below its normal CMC in the presence of AYR. Both hydrophobic and electrostatic interactions affect the aggregation process in aqueous solution. The dye effect on the CMC of CTAB was noted by a specific conductivity method as well. AYR–CTAB binding constant (Ks) and water–micelle partition co‐efficient (Kx) were quantified with the help of mathematical models employed to determine the partitioning of organic additives in the micellar phase. The number of dye molecules per micelle was estimated at particular CTAB concentrations above CMC, during this study.
Fatty Acid Composition of Plasma, Erythrocytes and Adipose: Their Correlations and Effects of Age and Sex
Authors: Ogura Tokuhiro , Takada Hideho , Okuno Masashi , Kitade Hiroaki , Matsuura Takashi , Kwon Masanori , Arita Seizaburo , Hamazaki Kei , Itomura Miho , Hamazaki Tomohito
Published: January 2010

The composition of fatty acids in abdominal subcutaneous adipose tissue and the correlation of fatty acid values of plasma and erythrocytes had not been reported in Japan. The aim of the present study was to investigate the fatty acid composition and correlation of plasma and erythrocyte phospholipids (PL) and adipose triacylglycerols (TG) in 75 adult patients admitted for non‐malignant diseases. We also examined the relationship of n‐3 and n‐6 polyunsaturated fatty acid (PUFA) with patients' characteristics. The total n‐3 PUFA were 11.2, 11.8 and 1.9%, and the ratios of n‐6/n‐3 were 2.41, 1.87 and 8.20 in plasma and erythrocyte PL and adipose TG, respectively. There were the highest correlations for total n‐3 PUFA and the n‐6/n‐3 ratio between plasma and erythrocyte PL and adipose TG. There was a positive correlation between n‐3 PUFAs and age, but a negative correlation was found between n‐6 PUFAs and age. There was no significant difference in the values of PUFAs in plasma and erythrocyte PL and adipose TG between men and women. The patients with cholesterol cholecystolithiasis showed a significantly lower proportion of eicosapentaenoic acid in plasma and erythrocyte PL than those of the other patients. Our findings suggest that PUFA in plasma and erythrocyte PL may be good biomarkers and more acceptable for studying participants than adipose TG.
Enzymatic Synthesis of Novel Feruloylated Lipids and Their Evaluation as Antioxidants
Authors: Zheng Yan , Branford‐White Christopher , Wu Xiao‐Mei , Wu Cheng‐Yao , Xie Jian‐Gang , Quan Jing , Zhu Li‐Min
Published: January 2010

Concerns about the use of chemical synthetic antioxidants that promote carcinogenesis has led to the development of natural antioxidants. Ferulic acid (4‐hydroxy‐3‐methoxy cinnamic acid, FA) is a monophenolic phenylpropanoid present in the plant kingdom. It has shown a high antioxidant capacity and biological activities, including antiviral, anticarcinogenic and antimicrobial ones. However, due to poor solubility in hydrophobic media, FA can only be used in aqueous environments and this is a key factor that to a certain extent limits its application and bioavailability. In the present study, novel feruloylated lipids 1(3)‐feruloyl‐monobutyryl‐glycerol (FMB) and 1(3)‐feruloyl‐dibutyryl‐glycerol (FDB) were prepared by lipase‐catalysed transesterification between FA and tributyrin. The structure of FMB and FDB was confirmed by NMR and ESI‐MS, respectively. The radical scavenging and antioxidant properties of FA, FMB and FDB were evaluated using several different antioxidant assays, including hydroxyl radical scavenging, superoxide anion radical scavenging, 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH·) radical scavenging, inhibition of peroxidation of linoleic acid and reducing power. The antioxidant activities decreased in the following order: BHT ≥ FMB > FDB > FA. The results suggested that FMB and FDB exhibited a strong effect against oxidation in lipophilic systems making them promising antioxidants.
Beyond Disparate Impact: Risk-based Pricing and Disparity in Consumer Credit History Scores
Authors: Spader Jonathan S.
Published: January 2010

Despite the increasing importance of credit scoring to an expanding range of activities, very little is known about the nature of the credit scoring process. This article examines the interaction of credit scoring with risk-based pricing, exploring the potential for credit scoring to contribute to the segmentation of low- and high-cost credit markets. Specifically, it uses a stylized example to illustrate the mechanism through which credit scores may capture disparities in surrounding credit markets, passing them into future periods and other credit markets. In the wake of mounting subprime foreclosures, this mechanism contains the potential to exacerbate the concentrated impacts of the subprime crisis in low-income and minority communities. The article examines this issue in the context of existing regulatory actions.
Non-uniqueness of weak solutions for the fractal Burgers equation
Authors: Alibaud Nathaël , Andreianov Boris
Published: January 2010

The notion of Kruzhkov entropy solution was extended by the first author in 2007 to conservation laws with a fractional Laplacian diffusion term; this notion led to well-posedness for the Cauchy problem in the

L^{\infty }

-framework. In the present paper, we further motivate the introduction of entropy solutions, showing that in the case of fractional diffusion of order strictly less than one, uniqueness of a weak solution may fail.

La notion de solution entropique de Kruzhkov a été étendue par Alibaud en 2007 aux lois de conservation avec un terme diffusif fractionnaire ; ceci a permis de démontrer que le prolème de Cauchy est bien posé dans le cadre

L^{\infty }

. Dans cet article, on montre que si l'ordre de l'opérateur de diffusion est strictement plus petit que un, alors il peut exister plusieurs solutions faibles ; on apporte ainsi une motivation supplémentaire à l'utilisation des solutions entropiques.
A priori bounds versus multiple existence of positive solutions for a nonlinear Schrödinger system
Authors: Weth Tobias , Dancer E.N. , Wei Juncheng
Published: January 2010

We study the set of solutions of the nonlinear elliptic system

\tag{P}
\begin{cases}
−\mathrm{\Delta }u + \lambda _{1}u = \mu _{1}u^{3} + \beta v^{2}u&\:\text{in }\Omega, \\
−\mathrm{\Delta }v + \lambda _{2}v = \mu _{2}v^{3} + \beta u^{2}v&\:\text{in }\Omega , \\
u,v > 0\:\text{in }\Omega ,\quad \:u = v = 0&\:\text{on }\partial \Omega ,
\end{cases}

in a smooth bounded domain

\Omega \subset \mathbb{R}^{N}

,

N⩽3

, with coupling parameter

\beta \in \mathbb{R}

. This system arises in the study of Bose–Einstein double condensates. We show that the value

\beta = −\sqrt{\mu _{1}\mu _{2}}

is critical for the existence of a priori bounds for solutions of (P). More precisely, we show that for

\beta > −\sqrt{\mu _{1}\mu _{2}}

, solutions of (P) are a priori bounded. In contrast, when

\lambda _{1} = \lambda _{2}

,

\mu _{1} = \mu _{2}

, (P) admits an unbounded sequence of solutions if

\beta ⩽−\sqrt{\mu _{1}\mu _{2}}

.
The effect of an ambidextrous supply chain strategy on combinative competitive capabilities and business performance
Authors: Kristal Mehmet Murat , Huang Xiaowen , Roth Aleda V.
Published: January 2010

This study investigates the influence of an ambidextrous supply chain strategy on manufacturers’ combinative competitive capabilities – the ability to excel simultaneously on competitive capabilities of quality, delivery, flexibility, and cost – and, in turn, on business performance. Drawing upon March's (1991) notions of exploration and exploitation, an ambidextrous supply chain strategy is conceptualized as a simultaneous pursuit of both explorative and exploitative supply chain practices. We operationalize this concept as a second‐order latent construct that captures the co‐variation between exploration and exploitation within the context of a manufacturer's supply chain management strategy. Using survey‐based data gathered from 174 U.S. manufacturers, we find that an ambidextrous supply chain strategy coincides with combinative competitive capabilities and business performance. Our empirical finding contradicts conventional wisdom that argues for tradeoffs between exploration and exploitation. Instead, our empirical results are in line with an emerging complementarity view advocating that supply chain managers build practices to gain operational efficiency while simultaneously searching for opportunities to gain operational advantages. In addition, we provide insights regarding the role of combinative capabilities in mediating the relationship between an ambidextrous supply chain strategy and business performance.
Uniqueness of pairings in Hopf-cyclic cohomology
Authors: Kaygun Atabey
Published: January 2010

We show that all pairings defined in the literature extending the Connes-Moscovici characteristic map in Hopf cyclic cohomology are isomorphic as natural transformations of derived double functors.
Higher homotopy operations and cohomology
Authors: Blanc David , Johnson Mark W. , Turner James M.
Published: January 2010

We explain how higher homotopy operations, defined topologically, may be identified under mild assumptions with (the last of) the Dwyer-Kan-Smith cohomological obstructions to rectifying homotopy-commutative diagrams.
Remarks on motivic homotopy theory over algebraically closed fields
Authors: Hu Po , Kriz Igor , Ormsby Kyle
Published: January 2010

We discuss certain calculations in the 2-complete motivic stable homotopy category over an algebraically closed field of characteristic 0. Specifically, we prove the convergence of motivic analogues of the Adams and Adams-Novikov spectral sequences, and as one application, discuss the 2-complete version of the complex motivic J -homomorphism.
Transition between Raman and Compton regimes in laser pulse amplification
Authors: CAIRNS R. A.
Published: January 2010

Amplification of a short laser pulse by means of its interaction with a counter-propagating long pulse in a plasma has been suggested as a way of reaching high intensities. Two regimes have been discussed in the literature. The first is the Raman regime, where the process is backward Raman scattering, described by the standard equations for resonant three-wave coupling, while the second is the Compton regime, in which electron dynamics is dominated by the ponderomotive force generated by the high-frequency wave, and electrons behave as single particles rather than producing a Langmuir wave. Our aim here is to use a simple model of electron dynamics to investigate the transition between these regimes.
Lower-hybrid waves generated by anomalous Doppler resonance in auroral plasmas
Authors: BINGHAM R. , CAIRNS R. A. , VORGUL I. , SHAPIRO V. D.
Published: January 2010

This paper describes some aspects of lower-hybrid wave activity in space plasmas. Lower-hybrid waves are particularly important since they can transfer energy efficiently between electrons and ions in a collisionless magnetized plasma. We consider the ‘fan’ or anomalous Doppler resonance instability driven by energetic electron tails and show that it is responsible for the generation of lower-hybrid waves. We also demonstrate that observations of their intensity are sufficient to drive the modulational instability.
Drift-Alfvén waves at the arbitrary ion Larmor radius scale in dusty plasmas
Authors: ONISHCHENKO O. G. , POKHOTELOV O. A. , KRASNOSELSKIKH V. V.
Published: January 2010

A set of magneto-hydrodynamic (MHD) equations that govern the nonlinear dynamics of drift-Alfvén waves with arbitrary spatial scales in comparison with the ion Larmor radius is derived. It is shown that in the linear limit a Fourier transform of these equations yields the dispersion relation which in the so-called Padé approximation corresponds to the fully kinetic theory.
The effects of a physical activity programme on the psychological wellbeing of older people in a residential care facility: an experimental study
Authors: CIAIRANO SILVIA , LIUBICICH MONICA EMMA , RABAGLIETTI EMANUELA
Published: January 2010

This experimental study aimed to analyse the effects of an aerobic activity intervention delivered by specially trained instructors to a sample of Italian older people living in a residential care facility. We assessed intervention effects on general health perception, perception that one's health represents a limitation for moderate and heavy physical activity, and positive and negative self-perception. The 36-item Short Form Health Survey Questionnaire (SF-36) was administered at pre-test and post-test to a sample of 22 older people (ten in the control group and 12 in the intervention group) of both genders with an average age of 80.6 years. The findings showed that: (a) the perception that one's health can limit moderate and heavy physical activity decreased significantly in the older people belonging to the intervention group between pre- and post-test, while it increased in the control group; (b) positive self-perception was found to be stable in the intervention group, while it decreased in the control group; and (c) there was no interaction between group and time with respect to both general health perception and negative self-perception. The exercise programme seemed to have a particularly positive effect on older people's beliefs about their ability to master successfully the activities of daily living such as walking and moving objects.
Formal and informal social participation of the ‘young-old’ in The Netherlands in 1992 and 2002
Authors: VAN GROENOU MARJOLEIN BROESE , DEEG DORLY J. H.
Published: January 2010

The study compares the formal and informal social participation of 60–69 year olds in The Netherlands in 1992 and 2002, and examines which attributes of the two cohorts favour social participation. Using data from the Longitudinal Aging Study Amsterdam, it was found that cohort differences in formal participation (as members of organisations, in volunteer work and in religious organisations) and in informal participation (having a large social network, and in cultural and recreational activities) associated with cohort differences in individual characteristics (level of education, health, employment status and marital status). Descriptive analyses showed an increase between 1992 and 2002 in all forms of participation except religious involvement. The 2002 cohort members were more educated and more engaged in employment, but in worse health and had a higher prevalence of divorce than the 1992 cohort members. Logistic regression analyses showed that the positive effect on social participation of the recent cohort's higher educational level was suppressed by the negative effect of their worse health. Being divorced had mixed effects on formal and informal participation, but the difference in the number of divorcees did not explain cohort differences in social participation. Interaction effects showed that the influence of sex and health on volunteer work and religious involvement changed over time. The paper concludes with a discussion of the prospects for higher levels of formal and informal social participation among future cohorts of young-older people.
A potential environment for lasing below 15 nm initiated by exploding wire in water
Authors: Kolacek K. , Prukner V. , Schmidt J. , Frolov O. , Straus J.
Published: January 2010

Proximity wall stabilized, fast (>4 × 1011 A/s), high current (>40 kA) discharges are capable to create long, dense, hot, stable, non-equilibrium plasma column, suitable e.g., for radiation amplification or even for lasing in extreme ultraviolet and soft X-ray region. Exploding wire in water resembles a metal-vapor-filled capillary with liquid, ever fresh wall (without any metallic deposit). Modeling of wire explosion (inclusive melting and boiling phase transitions, thermal diffusion, and variable conductivity) by the originally skinned driving current is described. Modeling results are compared with measurement of the discharge current and with side-on and end-on monitoring of H-alpha line emission. Analysis of H-alpha line profile is used for diagnostic of water-vapor layer around the wire. The differences between model and reality are attributed to the fact that the pressure dependence of material constants was neglected in the first approximation.
Study on Au + U + Au sandwich Hohlraum wall for ignition targets
Authors: Li Xin , Lan Ke , Meng Xujun , He Xiantu , Lai Dongxian , Feng Tinggui
Published: January 2010

In ignition targets designs, U or U based cocktail hohlraum are usually used because the Rosseland mean opacity of U is higher than for Au at the radiation temperature for ignition. However, it should be noted that the opacity of U is obviously lower than for Au when the radiation temperature falls into a low temperature region. Because the depth penetrated by radiation is only several micrometers under a 300eV drive, and also because there is a prepulse longer than 10 ns prepulse at temperatures lower than 170 eV in the radiation drive of ignition target designs. Therefore we propose an Au + U + Au sandwich hohlraum for ignition targets in this work. Compared to the cocktail, the sandwich not only remarkably simplifies the fabrication and uses less depleted U material, but also increases the albedo during the prepulse.
THE MOCK HEROIC, AN INTRUDER IN ARCADIA: GIROLAMO GIGLI, ANTONIO CALDARA AND L'ANAGILDA (ROME, 1711)
Authors: SMITH AYANA
Published: January 2010

In 1711 the opera L'Anagilda was performed in the private theatre of Francesco Maria Ruspoli, an important Roman patron of the Arcadian Academy. L'Anagilda's librettist (Girolamo Gigli) and composer (Antonio Caldara) were both associated with this society, but the opera contrasts with the basic goal of Arcadian aesthetics – namely, to reform literature and opera by imitating the structure of ancient Greek tragedy and the stylistic purity of Italian renaissance poets. Rather, Gigli and Caldara created an opera infused with comedy, interspersed with fantastic intermezzos and formulated according to a genre not endorsed by Arcadian literary critics, the mock heroic. This article explores topics related to one central question: why would Gigli and Caldara openly flout the literary precepts of Arcadia? Gigli was a career satirist whose works eventually caused him to be exiled from his native Siena, all of Tuscany and the Papal States, and to be expelled from three major literary academies, the Intronati, the Cruscanti and the Arcadians. Since he continually criticized the organizations to which he belonged for their narrow-mindedness, prejudice and hypocrisy, I contend that L'Anagilda represents a critique of Arcadia. Yet in the process, Gigli also shows the Arcadians that there is more than one path to verisimilitude and the imitation of classical models. Despite the mock-heroic characteristics of the libretto, Gigli adheres to some Arcadian structural requirements, and Caldara's score heightens the characterizations and the overall verisimilitude of the opera.
SOLOIST PARTICIPATION DURING THE TUTTIS OF EIGHTEENTH-CENTURY WOODWIND CONCERTOS
Authors: CAMPBELL CAREY
Published: January 2010

Although the common way to perform late eighteenth-century flute or oboe concertos today is for the soloist to rest during tutti passages, this is probably not what most composers had in mind. Recent research has shown that keyboard and violin soloists played an important role as orchestral members during the ritornellos of their concertos, the former providing a continuo part and the latter doubling the orchestral first violins. But what about concertos for flute or oboe? Were these soloists also to play during the tuttis, and if so, what? Primary source evidence (supported by statements in contemporary treatises) reveals that many eighteenth-century composers expected woodwind soloists to participate during all or some orchestral ritornellos. Printed and manuscript parts of the period reveal several types of soloist participation, suggesting that the practice was widespread yet also flexible. Reinstatement of the soloist in the tuttis, performing all of the music that eighteenth-century composers asked them to perform, would alter the way these concertos sound, in turn forcing a change in how they are perceived.
JOHN GEIB: BEYOND THE FOOTNOTE
Authors: STRANGE THOMAS , NEX JENNY
Published: January 2010

John Lawrence Geib has remained an often-cited but poorly known builder of keyboard instruments since the eighteenth century. Although historians have noted his patent for an escapement mechanism used on early English square pianos after 1787, little has been written about him, and much of that has now proven to be incomplete or untrue. A letter written by Geib to Benjamin Franklin has recently been made public. It outlines his early years in London and provides the foundation for further research into the remaining records and extant instruments. This information allows one to draw a more complete and historically correct picture of Geib and to place him in perspective with the other builders operating at the time. This article gives new details about his principal invention – the escapement mechanism – and the nature of his business during his early years in London. A full reproduction of the patent is included as an appendix.
Across‐arc geochemical trends in the Izu‐Bonin arc: Contributions from the subducting slab, revisited
Authors: Tollstrup Darren , Gill Jim , Kent Adam , Prinkey Debra , Williams Ross , Tamura Yoshihiko , Ishizuka Osamu
Published: January 2010

New Sr, Nd, Hf, and Pb isotope and trace element data are presented for basalts erupted in the Izu back arc. We propose that across‐arc differences in the geochemistry of Izu‐Bonin arc basalts are controlled by the addition of aqueous slab fluids to the volcanic front and hydrous partial melt of the slab to the back arc. The volcanic front has the lowest concentrations of incompatible elements, the strongest relative enrichments of fluid‐mobile elements, and the most radiogenic Sr, Nd, Hf, and Pb, suggesting the volcanic front is the result of high degrees of partial melting of a previously depleted mantle source caused by an aqueous fluid flux from the slab. Relative to the volcanic front, the back arc has higher concentrations of incompatible elements and elevated La/Yb and Nb/Zr, suggesting lower degrees of partial melting of a less depleted or even enriched mantle source. Positive linear correlations between fluid‐immobile element concentrations and the estimated degree of mantle melting suggest the slab contribution added to the mantle wedge in the Izu back arc is a supercritical melt. Pb, Nd, and Hf isotopes and Th/La systematics of back‐arc basalts are consistent with a slab melt composed of >90% altered oceanic crust and <10% sediment; that is, altered oceanic crust, not subducted sediment, dominates the slab contribution. High field strength element systematics require supercritical melts to be in equilibrium with residual rutile and zircon.
Seasonal Atlantic tropical cyclone hindcasting/forecasting using two sea surface temperature datasets
Authors: LaRow Timothy E. , Stefanova Lydia , Shin Dong‐Wook , Cocke Steven
Published: January 2010

Seasonal Atlantic basin tropical cyclone hindcasts are conducted from 1986–2005 using the Florida State University/Center for Ocean Atmospheric Prediction Studies atmospheric global spectral model and two sea surface temperature products. The two sea surface temperature products are: the National Oceanic and Atmospheric Administrations Climate Forecast System Model's 1 June forecast and the weekly observed sea surface temperatures. The hindcasts extend through the 180‐day Atlantic hurricane season. A four member ensemble is generated for each year using time‐lagged atmospheric initial conditions centered on 1 June of the respective year. The interannual variability of total number of Atlantic storms (tropical storms plus hurricanes) and accumulated cyclone energy using both sea surface temperature products yield high correlations which are statistically significant, although using the observed sea surface temperature product yields higher correlations. The results indicates that the Climate Forecast System Model's sea surface temperatures are suitable for use in real‐time seasonal tropical cyclone forecasting in the Atlantic basin in a two‐tiered approach.
Interannual ENSO variability forced through coupled atmosphere‐ocean feedback loops
Authors: Solomon Amy
Published: January 2010

El Niño/Southern Oscillation (ENSO) events are known to force atmospheric teleconnections that impact extratropical sea surface temperatures and surface winds. In this paper we use focused model experiments to investigate whether this extratropical variability can feedback to, and significantly impact, the Tropics through ocean Rossby waves. We use an atmospheric general circulation model coupled to a reduced gravity Pacific Ocean model to isolate these potential feedback loops and quantify their impact on ENSO variability. We find that anomalous winds and heat fluxes located in regions of maximum mean subduction in the subtropical North Pacific trigger ocean Rossby waves that take approximately four years to reach the equator. Most notably, we demonstrate that this feedback loop causes a primarily 2‐year ENSO, when only the Tropics is coupled, to shift to a more realistic broad 2–5 year range by damping ∼2 year variability and amplifying ∼4 year variability.
Geolocation of terrestrial gamma‐ray flash source lightning
Authors: Cohen M. B. , Inan U. S. , Said R. K. , Gjestland T.
Published: January 2010

Terrestrial gamma‐ray flashes (TGFs) are impulsive (∼1 ms) but intense sources of gamma‐rays associated with lightning activity and typically detected via low orbiting spacecrafts. We present the first catalog of precise (<30 km error) TGF source locations, determined via ground‐based detection of ELF/VLF radio atmospherics (or sferics) from lightning discharges, which enables precise geolocation of lightning locations. We present the distribution of source‐to‐nadir distances, established due to effects of Compton scattering on the escaping photons. We find that TGFs occur in coincidence with the lightning discharge, but with a few ms variance, and that a detectable sferic at long distances is nearly always present. The properties of TGF‐associated sferics and their connection to multiple‐peak TGFs are highly variable and inconsistent, and are classified into two categories.