bluuebunny/crossref_metadata_2025_split huggingface dataset:
CuIn1−xGaxSe2‐based thin‐film solar cells by the selenization of sequentially evaporated metallic layers
Authors: Caballero R. , Guillén C. , Gutiérrez M. T. , Kaufmann C. A. 
Published: December 2005

AbstractPolycrystalline CuIn1−xGaxSe2(CIGS) thin films were deposited by the non‐vacuum, near‐atmospheric‐pressure selenization of stacked metallic precursor layers. A study was carried out to investigate the influence of significant factors of the absorber on the solar cells performance. An efficiency enhancement was obtained for Cu/(In+Ga) atomic ratios between 0·93 and 0·95. The slope of the observed energy bandgap grading showed a strong influence on theVOCand the short circuit current densityJSC. An increase of the Ga content in the active region of the absorber was achieved by the introduction of a thin Ga layer on the Mo back contact. This led to an improvement of efficiency andVOC. Furthermore, an enhanced carrier collection was detected by quantum efficiency measurements when the absorber layer thickness was slightly decreased. Conversion efficiencies close to 10% have been obtained for these devices. Copyright © 2005 John Wiley & Sons, Ltd.
Back‐contact solar cells: a review
Authors: Kerschaver Emmanuel Van , Beaucarne Guy 
Published: December 2005

AbstractEver since the first publications by R.J. Schwartz in 1975, research into back‐contact cells as an alternative to cells with a front and rear contact has remained a research topic. In the last decade, interest in back‐contact cells has been growing and a gradual introduction to industrial applications is emerging. The goal of this review is to present a comprehensive summary of results obtained throughout the years. Back‐contact cells are divided into three main classes: back‐junction (BJ), emitter wrap‐through (EWT) and metallisation wrap‐through (MWT), each introduced as logical descendents from conventional solar cells. This deviation from the chronology of the developments is maintained during the discussion of technological results. In addition to progress on manufacturing these cells, aspects of cell modelling and module manufacturing are discussed and an outlook towards industrial implementation is presented. Copyright © 2005 John Wiley & Sons, Ltd.
Synthesis and properties of new fluorene‐based polyquinoxalines with an ether linkage in the main chain for light‐emitting diodes
Authors: Jung Sung‐Hyun , Kim Dong Young , Cho Hyun‐Nam , Suh Dong Hack 
Published: December 2005

AbstractA new series of fluorene‐based polyquinoxalines with an ether linkage in the main chain were prepared by the polycondensation reaction between a tetraketone monomer and 3,3′,4,4′‐tetraaminodiphenyl ether. The polycondensation was usually carried out in m‐cresol. The resulting polymers (P1–P3) [P1 = poly(quinoxaline‐co‐9,9‐dihexyl‐2,7‐dimethyl‐9H‐fluorene) P2 = poly(quioxaline‐co‐9,9‐dihexyl‐9‐pentyl‐2,7‐di‐p‐tolyl‐9H‐fluorene) P3 = poly(quioxaline‐co‐9,9‐bis‐(4‐methoxy‐phenyl)‐2,7‐dimethyl‐9H‐fluorene)] showed good solubility in common organic solvents and high thermal stability with only a 5% weight loss up to 440 °C. P1 and P2 had very high glass‐transition temperatures of 212 and 223 °C, respectively, whereas P3 did not show any phase‐transition temperature in repeated scans up to 300 °C. All the polymers in photoluminescence showed blue emissions in the range of 432–465 nm, both in chloroform solutions and in thin films. Light‐emitting diode devices of the configuration indium tin oxide/poly(3,4‐ethylenedioxythiophene)/polymer:poly(N‐vinylcarbazole) blend (2:8)/LiF/Al were fabricated with P1 or P2 and emitted blue light with electroluminescence peak wavelengths of 434 and 448 nm, respectively. The maximum brightness and the external quantum efficiency of P1 were 0.56 μW/cm2 at 29 V and 0.056%, whereas P2 showed 0.50 μW/cm2 at 34 V and a relatively low value of 0.015%, respectively. Cyclic voltammetry studies revealed that these polymers possessed low‐lying ionization potential energy levels ranging from −5.49 to −5.86 eV and low‐lying electron affinity energy levels ranging from −2.65 to −2.88 eV. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1189–1198, 2006
Synthesis of poly(glycolic acid‐alt‐12‐aminododecanoic acid): The thermal polymerization kinetics of sodium N‐chloroacetyl‐12‐aminododecanoate
Authors: Botines E. , Franco L. , Ramis X. , Puiggalí J. 
Published: December 2005

AbstractA new regular poly(ester amide) consisting of glycolic acid and 12‐aminododecanoic acid was synthesized by a thermal polycondensation method involving the formation of a metal halide salt. Polymerization could start in liquefied or solid phases, depending on the reaction temperature. The polymerization kinetics were investigated by isothermal and nonisothermal isoconversional methods. The reaction model was selected with both Coats–Redfern and isokinetic relationships. The activation energy was higher when the reaction took place mainly in the solid state. A compensation effect was found between the frequency factor and the activation energy. The thermal properties of the new polymer were studied as well as the isothermal crystallization from the melt state. Melt‐grown spherulites were studied by means of polarizing optical microscopy. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1199–1213, 2006
Characterization of elastomeric blends by atomic force microscopy
Authors: Achalla P. , McCormick J. , Hodge T. , Moreland C. , Esnault P. , Karim A. , Raghavan D. 
Published: December 2005

AbstractThe bulk mechanical properties of a blend of elastomers are found to depend on the micro and nano scale morphology of the phases of the materials in the blend. In this study, we examine the phase morphology of blends of incompatible elastomers using Atomic Force Microscopy (AFM). Specifically, nanoindentation and Tapping Mode AFM (TMAFM) imaging techniques are used as experimental tools for mapping the composition of unfilled elastomeric blends. Depending on the composition of the blend, either co‐continuous or discontinuous domain/matrix morphology is observed. To identify the different components in bromobutyl (BIIR)/natural rubber (NR) blends, nanoscale indentation measurements were made on the observed phase‐separated regions. Results from force mode AFM and mechanical measurements of bulk NR and BIIR are used to assist in the interpretation of the TMAFM results for the BIIR/NR blends. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 492–503, 2006
Conformational analysis of a potent SSTR3‐selective somatostatin analogue by NMR in water solution
Authors: Gairí Margarida , Saiz Pilar , Madurga Sergio , Roig Xavier , Erchegyi Judit , Koerber Steven C. , Claude Reubi Jean , Rivier Jean E. , Giralt Ernest 
Published: December 2005

AbstractThe three‐dimensional structure of a potent SSTR3‐selective analogue of somatostatin, cyclo(3–14)H‐Cys3‐Phe6‐Tyr7‐D‐Agl8(Nβ Me, 2‐naphthoyl)‐Lys9‐Thr10‐Phe11‐Cys14‐OH (des‐AA1, 2, 4, 5, 12, 13[Tyr7, D‐Agl8(Nβ Me, 2‐naphthoyl)]‐SRIF) (peptide 1) has been determined by 1H NMR in water and molecular dynamics (MD) simulations. The peptide exists in two conformational isomers differing mainly by the cis/trans isomerization of the side chain in residue 8. The structure of 1 is compared with the consensus structural motifs of other somatostatin analogues that bind predominantly to SSTR1, SSTR2/SSTR5 and SSTR4 receptors, and to the 3D structure of a non‐selective SRIF analogue, cyclo(3–14)H‐Cys3‐Phe6‐Tyr7‐D‐2Nal8‐Lys9‐Thr10‐Phe11‐Cys14‐OH (des‐AA1, 2, 4, 5, 12, 13[Tyr7, D‐2Nal8]‐SRIF) (peptide 2). The structural determinant factors that could explain selectivity of peptide 1 for SSTR3 receptors are discussed. Copyright © 2005 European Peptide Society and John Wiley & Sons, Ltd.
Interlinkages between internal and international migration and development in the Asian region
Authors: Skeldon Ronald 
Published: December 2005

AbstractThis paper examines the linkages between systems of internal migration and systems of international migration in the Asian region. In the context of changing global patterns of international migration on the one hand and urbanisation on the other, the paper briefly examines the evolution of two different traditions in migration research and policy: those concerned with international and those concerned with internal migration. Recognising that there is some blurring in any distinction between the two types of migration, the paper hypothesises that there are sufficient differences between the two systems to warrant separate identification. Although both can operate simultaneously, the paper goes on to posit two scenarios: that internal migration can lead to international migration; and that international migration can lead to internal migration. Evidence from various parts of South and East Asia is employed to examine the validity of these statements.There is no single evolutionary path, and examples of both scenarios are found in Asia. The concentration of populations in urban areas can give rise to later international movements, but these international migrations themselves, by creating vacuums in areas of origin, can in turn generate internal migration. The history of colonial contact, too, can initiate international migration from particular areas, not necessarily just urban, which give rise to later internal movements. Internal and international migrations are integrated and it is necessary to consider them as a unified system rather than in isolation. The hierarchical movements link richer and poorer groups together and need to be understood in the context of the implementation of programmes of poverty alleviation. By attempting to link internal and international migration, this paper is a small step towards the creation of a more integrated framework for the study of population movement. Copyright © 2006 John Wiley & Sons, Ltd.
Balancing move and work: women's labour market exits and entries after family migration
Authors: Clark William A. V. , Huang Youqin 
Published: December 2005

AbstractA substantial literature has examined the nature of mobility and migration and the link to workforce participation. In general that literature has documented the disadvantages to women who move or migrate with a partner during the mobility or migration process, but it suggests, especially for the US, that the disadvantage is temporarily limited. This study of the same process in the British labour market reaffirms a temporary deficit‐effect of two‐worker migration for women, but unlike the US labour market the process of re‐entry seems slower. There are modest monetary gains from mobility and migration, but these gains come for some families only when women enter the labour force after migration. The study reconfirms the importance of gender in the migration and mobility processes. Income, for women, recovers more slowly if a birth was registered in the migration interval. Copyright © 2006 John Wiley & Sons, Ltd.
International migration and the Rainbow Nation
Authors: Lucas David , Amoateng Acheampong Yaw , Kalule‐Sabiti Ishmael 
Published: December 2005

AbstractRecent statistics suggest that emigration from South Africa is accelerating while documented immigration remains at low levels. Primary analysis of a 10% sample of the overseas‐born in South Africa from the 1996 census confirmed that Black immigrants to South Africa were shown to be predominantly unskilled males, who were no better qualified than the Black population in general. This contrasts with the apartheid era when South Africa built up a stock of overseas‐born skilled workers, mostly Whites, which was not replenished in the 1990s, partly because of restrictive immigration policies.The UK is the major destination for South Africans but lacks detailed data on the characteristics of the immigrants. The second destination is Australia and New Zealand combined. Comparisons are made with published census data on the South Africa‐born in Australia and New Zealand. A majority of emigrants have post‐school qualifications and professional occupations, reflecting the selective immigration criteria of Australia and New Zealand. The analysis confirms the importance of human capital to potential emigrants even though they may wish to move for non‐economic reasons. It also supports the view that South Africa had moved from a brain exchange of Whites to a brain drain, thus compounding a national shortage of skilled workers. Copyright © 2006 John Wiley & Sons, Ltd.
Structural and electrical properties of Mo/n‐GaN Schottky diodes
Authors: Reddy V. Rajagopal , Ramesh C. K. , Choi Chel‐Jong 
Published: December 2005

AbstractThe electrical and structural properties of molybdenum (Mo) Schottky contact to n‐type GaN (4.07 × 1018 cm–3) have been investigated before and after annealing at 600 °C. Measurements show that the Schottky barrier height of the as‐deposited sample was 0.81 eV (I–V) and 1.02 eV (C–V), respectively. It is shown that when the sample is annealed at 400 °C the Schottky barrier height slightly decreases to 0.74 eV (I–V) and 0.92 eV (C–V), respectively. However, the barrier height degraded to 0.56 and 0.73 eV when the sample was annealed at 600 °C for 1 min in nitrogen ambient. Based on the Auger electron microscopy and X‐ray diffraction results, the formation of nitride phases at the Mo/n‐GaN interface could be the reason for degradation of Schottky barrier height upon annealing at 600 °C. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Superconductivity of InN
Authors: Inushima T. , Kato N. , Takenobu T. , Motokawa M. 
Published: December 2005

AbstractThe crystal structure of InN is wurtzite and its interplanar spacing of (10$ \bar 1 $1) is almost the same as that of tetragonal In(101). The crystallographic similarity produces many problems to solve about the electronic properties of semiconducting InN. Above all, there is a controversy over the possibility that In layers in InN that contains poly‐crystalline phase couple by tunneling and exhibit no substantial depression of their superconducting transition temperature from the bulk In value. Here we present a superconductor to insulator transition in highly disordered InN with grains having a (10$ \bar 1 $1) plane parallel to sapphire (0001). (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of semiconducting electrodes on properties of thin ferroelectric films
Authors: Glinchuk M. D. , Zaulychny B. Y. , Stephanovich V. A. 
Published: December 2005

AbstractThe influence of semiconducting electrodes on the properties of thin ferroelectric films is considered within the framework of the phenomenological Ginzburg–Landau theory. The contribution of the electric field produced by charges in the electrodes allowing for the screening length of the carriers is included in the functional of the free energy and so in the Euler–Lagrange equation for the film's polarization. Application of the variational method to the solution of this equation allows the transformation of the free energy functional into a conventional type of free energy with renormalized coefficients. The obtained dependence of the coefficients on the film thickness, temperature, electrodes, carrier screening length, and other parameters make it possible to calculate the dependence of the properties on these parameters by conventional minimization of the free energy. The semiconducting carrier screening length was shown to influence strongly the film's properties and critical parameters of the thickness‐induced phase transition. At some fixed temperature and thickness of the film electrode an induced phase transition from the ferroelectric to the paraelectric phase is shown to exist when the screening length of the carriers is larger than some critical value. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Temperature‐induced phase transition in simulated amorphous Al2O3
Authors: Van Hoang Vo , Hung Nguyen Hoang 
Published: December 2005

AbstractOur previous simulation studies indicated the existence of pressure‐induced phase transition in liquid and amorphous Al2O3. In the current paper, we present the structural transformation of simulated amorphous Al2O3 from an octahedral to a tetrahedral network structure by heating from the high‐density amorphous (hda) model at constant pressure P = 0 GPa. The structure of the models was analyzed through the partial radial distribution functions (PRDFs), coordination number distributions, bond‐angle distributions and interatomic distances. Furthermore, significant differences in structural characteristics of low‐density amorphous (lda) models obtained by heating from the hda one and by cooling from the low‐density melt have been found and are presented. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
EPR of Nd3+ in congruent and nearly stoichiometric lithium niobate
Authors: Malovichko G. , Grachev V. , Okulov S. , Kokanyan E. , Henecker F. , Hofstaetter A. , Schirmer O. 
Published: December 2005

AbstractLithium niobate crystals doped with neodymium were studied with the help of electron paramagnetic resonance, EPR in the temperature range of 4.2–20 K. Tremendous narrowing of the EPR lines in nearly stoichiometric samples in comparison with congruent ones allowed us to distinguish four non‐equivalent centers, as well as line splitting caused by hyperfine interaction of neodymium electrons with nuclear spins of both magnetic isotopes 143Nd and 145Nd. It is shown that one of the centers has axial C3 symmetry, whereas all others have lowest C1 symmetry due to presence of intrinsic defects or/and charge compensation defects in the near neighborhood of Nd3+. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A study of phase transition in (NH4)3WO3F3 oxyfluoride by Raman scattering
Authors: Krylov A. S. , Gerasimova J. V. , Vtyurin A. N. , Fokina V. D. , Laptash N. M. , Voyt E. I. 
Published: December 2005

AbstractRaman scattering spectra of perovskite‐like (NH4)3WO3F3 oxyfluoride are studied in the 70–3600 cm–1 frequency range and the 93–323 K temperature range including the transition point from orientationally disordered cubic phase into the lower symmetry one. Internal vibrations of ammonium ions and WO3F3 octahedra have been found to exhibit transition anomalies. Analysis of measurements suggests that the transition under study is due mainly to the ordering of octahedra. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
MADoSPRO: a new approach to molecular modelling studies on a series of DNA minor groove binders
Authors: Lauria Antonino , Diana Patrizia , Barraja Paola , Montalbano Alessandra , Cirrincione Girolamo , Dattolo Gaetano , Almerico Anna Maria 
Published: December 2005

AbstractThe aim of this work was devoted to develop a method to predict ΔG values for a series of minor groove binders. Starting from a matrix of docking dataset for 10 minor groove binders (known and not) to 20 DNA fragments, with various sequences, it was possible to analyze the interaction modes and to calculate the ΔG value for new derivatives through MADoSPRO procedure. The method allowed, through the QSPR analysis, to characterize the type of interactions in such complexes, that was demonstrated to be related to quantum chemical and electrostatic descriptors, in agreement with the information available in literature on the structural requirements of specific minor groove ligands.
Fault‐tolerant control of nonlinear processes: performance‐based reconfiguration and robustness
Authors: Mhaskar Prashant , Gani Adiwinata , Christofides Panagiotis D. 
Published: December 2005

AbstractThis work considers the problem of control system/actuator failures in nonlinear processes subject to input constraints and presents two approaches for fault‐tolerant control that focus on incorporating performance and robustness considerations, respectively. In both approaches, first a family of candidate control configurations, characterized by different manipulated inputs, is identified for the process under consideration. Performance considerations are first incorporated via the design of a Lyapunov‐based predictive controller that enforces closed‐loop stability from an explicitly characterized set of initial conditions (computed using an auxiliary Lyapunov‐based nonlinear controller). A hierarchical switching policy is derived, that uses stability considerations (evaluated via the presence of the state in the stability region of a control configuration) to ascertain the suitability of a candidate backup configuration and then performance considerations are again considered in choosing between the suitable backup configurations. Next, we consider the problem of implementing fault‐tolerant control to nonlinear processes subject to input constraints and uncertainty. To this end, we first design a robust hybrid predictive controller for each candidate control configuration that guarantees stability from an explicitly characterized set of initial conditions, subject to uncertainty and constraints. A switching policy is then derived to orchestrate the activation/deactivation of the constituent control configurations. Finally, simulation studies are presented to demonstrate the implementation and evaluate the effectiveness of the proposed fault‐tolerant control method. Copyright © 2005 John Wiley & Sons, Ltd.
Robust control for an uncertain chemostat model
Authors: Gouze Jean‐Luc , Robledo Gonzalo 
Published: December 2005

AbstractIn this paper we consider a control problem for an uncertain chemostat model with a general growth function and cell mortality. This uncertainty affects the model (growth function) as well as the outputs (measurements of substrate). Despite this lack of information, an upper bound and a lower bound for those uncertainties are assumed to be known a priori. We build a family of feedback control laws on the dilution rate, giving a guaranteed estimation on the unmeasured variable (biomass), and stabilizing the two variables in a rectangular set, around a reference value of the substrate. We give two realistic applications of this control law to a depollution process and to phytoplankton culture. Copyright © 2005 John Wiley & Sons, Ltd.
Linear PI control of batch exothermic reactors with temperature measurement
Authors: Alvarez‐Ramirez Jose , Alvarez Jesus 
Published: December 2005

AbstractA wide variety of speciality materials and fine chemicals such as plastics, pharmaceutical and microelectronics components are produced in batch reactors. The nonlinear, transient and finite‐time features of the batch reactors give rise to complex process and control design problems. In particular, the safe operation of exothermic reactors depends on the adequate functioning of a temperature tracking controller, and to a good extent, the same is true for the attainment of a suitable compromise between productivity and product quality attributes. While the stabilization problem of continuous exothermic chemical reactors has been recently addressed with rigorous asymptotic‐stability methods, the same kind of studies have not yet been performed for the finite‐time batch reactor case. In this paper, the problem of designing a temperature tracking controller for an exothermic batch reactor, with n species and m reactions, is addressed under the following premises: (i) only the reactor temperature is measured, (ii) the (typically uncertain) reaction rate and heat exchange nonlinear functions are unknown, (iii) the controller must be linear and easy to tune, and (iv) the closed‐loop reactor motion must be stable in a suitable sense. The combination of industrial‐oriented inventory control concepts in conjunction with singular perturbation results yields a linear controller with a combined feedforward‐PI feedback structure, antireset windup scheme, and conventional‐like tuning rules. The controller: (i) tracks, arbitrarily fast and close, a prescribed temperature trajectory, with admissibly deviated concentration motions, and (ii) quickly recovers the behaviour of an exact model‐based nonlinear I/O linearizing controller. The proposed design is put in perspective with the geometric and IMC nonlinear control approaches. Copyright © 2005 John Wiley & Sons, Ltd.