bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis and characterization of crosslinkable latex with interpenetrating network structure based on polystyrene and polyacrylate
Authors: Zhang Ji‐De , Yang Mu‐Jie , Zhu Yang‐Rong , Yang Huan 
Published: May 2006

AbstractFunctional poly[styrene‐co‐(2‐ethylhexyl acrylate)‐co‐(1,6‐hexanediol diacrylate)]/poly[(methyl methacrylate)‐co‐(butyl acrylate)‐co‐(methacrylic acid)‐co‐(diacetone acrylamide)] (PS/PA) semi‐interpenetrating polymer networks (semi‐LIPNs) containing ketone carboxyl groups were synthesized by two‐stage emulsion polymerization, and characterized by Fourier transform infrared, transmission electron microscopy, dynamic light scattering and DSC. A unique feature of the PS/PA semi‐LIPNs is their ability to crosslink and form thermosetting full‐IPN polymers through the reaction of ketone carboxyl and hydrazide in the course of film formation at ambient temperatures. Series of latex particles with various levels of crosslinking density in the PS and PA domain and varied composition of PS/PA LIPNs were obtained. The effects of the LIPN PS/PA composition and the level of crosslinking density in the PS and PA domain on film density, swell ratio, mechanical properties and contact angle with water were investigated. Maximum synergy effects obtained at around 50/50 (PS/PA) in terms of mechanical properties, density and contact angle with water indicate that the maximum degree of interpenetration is obtained at this composition. Copyright © 2006 Society of Chemical Industry
Contact wetting angle as a characterization technique for processing CdTe/CdS solar cells
Authors: Angelo M. S. , McCandless B. E. , Birkmire R. W. , Rykov S. A. , Chen J. G. 
Published: May 2006

AbstractThe feasibility of measuring contact wetting angles to characterize processing induced changes to thin film semiconductors in CdTe/CdS solar cells is evaluated. The contact angles of water and formamide are used to determine the polar and dispersive surface energies of the thin films using two analysis methods. Changes in surface energies resulting from processing are correlated to changes in surface chemistry and structure detected by glancing incidence X‐ray diffraction (GIXRD), X‐ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). Surface energies are evaluated for sputtered In2O3:SnO2, chemical surface‐deposited CdS, and physical vapor‐deposited (PVD) CdTe thin films under as‐deposited and treated conditions. Treatments include thermal anneal in air, argon, and CdCl2ambient as well as surface etching. Indium tin oxide (ITO) and CdS films exhibit increased polar surface energy corresponding to enhanced crystallization of surfaces resulting from processing and increasing CdS growth temperature. Native oxidation of PVD CdTe (111)‐oriented film surfaces occurs rapidly and is readily detected by changes in contact angle. Surface energies of PVD (111)‐oriented CdTe stored under various humidities prior to processing are energetically similar due to native oxidation. The polar energy of CdTe surfaces is affected by the addition or removal of crystalline surface oxides during film processing. Copyright © 2006 John Wiley & Sons, Ltd.
A simulation‐based method for the comprehensive analysis of effective lifetime from photoconductance
Authors: Bueno G. , Recart F. , Jimeno J. C. 
Published: May 2006

AbstractThis paper presents a method for estimating recombination parameters in the volume and surface of solar cell precursors throughout the manufacturing process, taking into account several effects that are generally neglected. The technique is based on the comprehensive reconstruction of the effective lifetime assuming a set of fundamental parameters and its comparison to the experimental data obtained from the photoconductance measured under uniform generation in quasi‐steady state conditions. The analysis starts from the semianalytical solution of the minority carrier profiles in the structures under test. This analysis overcomes the usual flat profile approximation and presents important advantages. It allows the asymmetry presented by the solar cell precursors to be taken into account and deals with a wide range of surface conditions: emitters, bare silicon or dielectric passivations. The model also accounts for the effect of the electric field in the volume, and implements several phenomena that are sometimes neglected but are relevant when measuring industrial solar cells precursors: the injection dependence of mobilities and recombination lifetimes, the presence of non‐recombinant traps and the Depletion Region Modulation effect. The estimation technique requires uniform generation, which greatly facilitates the calculation of the carrier profiles and allows for a simple method for the auto calibration of the light absorption. Copyright © 2006 John Wiley & Sons, Ltd.
Effective efficiency of PV modules under field conditions
Authors: Topi Marko , Brecl Kristijan , Sites James 
Published: May 2006

AbstractThe conversion efficiency of photovoltaic modules varies with irradiance and temperature in a predictable fashion, and hence the effective efficiency averaged over a year under field conditions can be reliably assessed. The suggested procedure is to define the efficiency versus irradiance and temperature for a specific module, collect the local irradiance and temperature data, and combine the two mathematically, resulting in effective efficiency. Reasonable approximations simplify the process. The module performance ratio is defined to be the ratio of effective efficiency to that under standard test conditions. Variations of the order of 10% in this factor among manufacturers, primarily the result of the differences in effective series resistance and leakage conductance, are not unusual. A focus on these parameters that control the effective efficiency should provide a path to PV modules with improved field performance. Copyright © 2006 John Wiley & Sons, Ltd.
Dependability analysis of stand‐alone photovoltaic systems
Authors: Díaz Pablo , Egido Miguel Ángel , Nieuwenhout Frans 
Published: May 2006

AbstractLong‐term performance of PV stand‐alone systems is analysed in this work in terms of dependability. On one side, the quality of a PV system, the energy service supplied to the users, depends on the initial design and sizing and on the component ageing that progressively decreases the availability of supply on demand (energy reliability). On the other side, technical failures lead to system stoppage until repairing is performed (technical reliability), which is crucial in real rural electrification applications. All those factors are analysed together with the basis of an extended field, laboratory and bibliographic review work. Copyright © 2006 John Wiley & Sons, Ltd.
Amino acid substitutions affecting protein dynamics in eglin C do not affect heat capacity change upon unfolding
Authors: Gribenko Alexey V. , Keiffer Timothy R. , Makhatadze George I. 
Published: May 2006

AbstractThe heat capacity change upon unfolding (ΔCp) is a thermodynamic parameter that defines the temperature dependence of the thermodynamic stability of proteins; however, physical basis of the heat capacity change is not completely understood. Although empirical surface area‐based calculations can predict heat capacity changes reasonably well, accumulating evidence suggests that changes in hydration of those surfaces is not the only parameter contributing to the observed heat capacity changes upon unfolding. Because packing density in the protein interior is similar to that observed in organic crystals, we hypothesized that changes in protein dynamics resulting in increased rigidity of the protein structure might contribute to the observed heat capacity change upon unfolding. Using differential scanning calorimetry we characterized the thermodynamic behavior of a serine protease inhibitor eglin C and two eglin C variants with altered native state dynamics, as determined by NMR. We found no evidence of changes in ΔCp in either of the variants, suggesting that changes in rigidity do not contribute to the heat capacity change upon unfolding in this model system. Proteins 2006. © 2006 Wiley‐Liss, Inc.
Dynamic control of allosteric antagonism of leukocyte function antigen‐1 and intercellular adhesion molecule‐1 interaction
Authors: Nam Kiyean , Maiorov Vladimir , Feuston Bradley , Kearsley Simon 
Published: May 2006

AbstractLeukocyte function associated antigen‐1 (LFA‐1) plays a critical role in T cell migration and has been recognized as a therapeutic target for immune disorders. Several classes of small molecule antagonists have been developed to block LFA‐1 interaction with intercellular adhesion molecule‐1 (ICAM‐1). Recent structural studies show that the antagonists bind to an allosteric site in the I‐domain of LFA‐1. However, it is not yet clear how these small molecules work as antagonists since no significant conformational change is observed in the I‐domain–antagonist complex structures. Here we present a computational study suggesting how these allosteric antagonists affect the dynamics of the I‐domain. The lowest frequency vibrational mode calculated from an LFA‐1 I‐domain structure shows large scale “coil‐down” motion of the C‐terminal α7 helix, which may lead to the open form of the I‐domain. The presence of an allosteric antagonist greatly reduces this motion of the α7 helix as well as other parts of the I‐domain. Thus, our study suggests that allosteric antagonists work by eliminating breathing motion that leads to the open conformation of the I‐domain. Proteins 2006. © 2006 Wiley‐Liss, Inc.
The antifouling activity of some juvenoids on three species of acorn barnacle, Balanus
Authors: Skattebøl Lars , Nilsen Nils Olav , Stenstrøm Yngve , Andreassen Petter , Willemsen Peter 
Published: May 2006

AbstractAnalogues of insect juvenile hormones (juvenoids) have been tested for settling inhibition of cyprids from three species of barnacle, Balanus balanoides (L.), Balanus improvisus Darwin and Balanus amphitrite Darwin. Some 3‐alkoxypyridine derivatives exhibited strong activity at mg litre−1 concentrations; 3,7‐dimethyloctyl 2‐methyl‐5‐pyridyl ether (8) gave an EC50 of 0.006 mg litre−1 when tested on B. balanoides. When compound 8 and similar juvenoids were incorporated into paints, test panels kept in seawater for 8 months were free of barnacles. Copyright © 2006 Society of Chemical Industry
2D and 3D Quantitative Structure‐Activity Relationship Studies on a Series of bis‐Pyridinium Compounds as Choline Kinase Inhibitors
Authors: Janardhan S. , Srivani P. , Sastry G. Narahari 
Published: May 2006

AbstractTwo‐dimensional (2D) and three‐dimensional (3D) quantitative structure activity relationship (QSAR) studies have been carried out on a series of 55 bis‐pyridinium compounds to find out the structural requirements of choline kinase (ChoK) inhibitors. The best predictions were obtained from the model where 44 compounds were considered in the training set and the remaining 11 in the test set. The heuristic and BMLR methods resulted with r2 and q2 values of 0.86, 0.83 and 0.87, 0.84 respectively. The obtained Fisher and S2 values for both the methods are 49.02 and 54.05, 0.053 and 0.0397 respectively. The best model for 3D‐QSAR has been obtained with r2=0.97, q2 = 0.58 and r$\rm{ {_{pred}^{2}}}$=0.68 when CoMFA fields were used. The r2 of 0.85, q2 of 0.55 and r$\rm{ {_{pred}^{2}}}$=0.66 have been observed when CoMSIA fields were used. The results that are obtained from 2D and 3D‐QSAR studies may provide useful insights into the roles of various substitution patterns on the bis‐pyridinium skeleton and may also help to design more potent compounds.
Utility of porous graphitic carbon stationary phase in quantitative liquid chromatography/tandem mass spectrometry bioanalysis: quantitation of diastereomers in plasma
Authors: Xia Yuan‐Qing , Jemal Mohammed , Zheng Naiyu , Shen Xiaohang 
Published: May 2006

AbstractA major challenge in selecting an appropriate stationary phase for diastereomeric separation is that it is difficult to predict which of the commercially available stationary phases could achieve the required liquid chromatographic (LC) separation. This work describes the selection and evaluation of a porous graphitic carbon (PGC) column coupled with tandem mass spectrometry (MS/MS) for the simultaneous quantitation of an experimental drug candidate (I), its two diastereomeric metabolites (II and III), and its demethylated metabolite (IV) in rat plasma. In addition, we investigated the PGC column for the separation of another drug candidate (VI), its two diastereomeric metabolites (VII and VIII) and its ketone metabolite (IX). The PGC column showed excellent chromatographic resolution for the two diastereomers II and III, as well as for VII and VIII. In contrast, the required resolution for the diastereomers II and III could not be achieved using silica‐bonded C18, C30, phenyl, perfluorinated, polar embedded and polar end‐capped phases. The PGC column showed ruggedness with excellent reproducibility of retention times, peak symmetry and response over a period of more than 400 injections of a plasma acetonitrile‐precipitation extract. Excellent accuracy and precision were achieved, with accuracy of 94–108% and intra‐ and inter‐run precision within 9%. This work indicates that PGC is a valuable addition to the repertoire of LC columns used for quantitative LC/MS/MS bioanalysis, especially where the separation and quantitation of diastereomeric analytes is involved. Copyright © 2006 John Wiley & Sons, Ltd.
Fixation of nitrogen in an electrospray mass spectrometer
Authors: Levine Rodney L. 
Published: May 2006

AbstractThe formation of an iron‐nitrogen compound in an electrospray ionization instrument is reported. The iron was released from the stainless steel electrospray needle by acetic acid added to displace trifluoroacetic acid and the nitrogen was present as the drying gas. The product is an iron nitride ion, [N2FeOH]1+, m/z 100.9438, and is capable of addition to peptides and proteins. Published in 2006 by John Wiley & Sons, Ltd.
Combined infrared multiphoton dissociation and electron‐capture dissociation using co‐linear and overlapping beams in Fourier transform ion cyclotron resonance mass spectrometry
Authors: Mihalca Romulus , van der Burgt Yuri E. M. , McDonnell Liam A. , Duursma Marc , Cerjak Iliya , Heck Albert J. R. , Heeren Ron M. A. 
Published: May 2006

AbstractA novel set‐up for Fourier transform ion cyclotron resonance mass spectrometry (FTICR) is reported for simultaneous infrared multiphoton dissociation (IRMPD) and electron‐capture dissociation (ECD). An unmodified electron gun ensures complete, on‐axis overlap between the electron and the photon beams. The instrumentation, design and implementation of this novel approach are described. In this configuration the IR beam is directed into the ICR cell using a pneumatically actuated mirror inserted into the ion‐optical path. Concept validation was made using different combinations of IRMPD and ECD irradiation events on two standard peptides. The ability to perform efficient IRMPD, ECD and especially simultaneous IRMPD and ECD using lower irradiation times is demonstrated. The increase in primary sequence coverage, with the combined IRMPD and ECD set‐up, also increases the confidence in peptide and protein assignments. Copyright © 2006 John Wiley & Sons, Ltd.
N‐terminal H3/D3‐acetylation for improved high‐throughput peptide sequencing by matrix‐assisted laser desorption/ionization mass spectrometry with a time‐of‐flight/time‐of‐flight analyzer
Authors: Noga Marek J. , Asperger Arndt , Silberring Jerzy 
Published: May 2006

AbstractA novel method for peptide sequencing by matrix‐assisted laser desorption/ionization mass spectrometry with a time‐of‐flight/time‐of‐flight analyzer (MALDI‐TOF/TOF) is presented. A stable isotope label introduced in the peptide N‐terminus by derivatization, using a 1:1 mixture of acetic anhydride and deuterated acetic anhydride, allows for easy and unambiguous identification of ions belonging either to the N‐ or the C‐terminal ion series in the product ion spectrum, making sequence assignment significantly simplified. The good performance of this technique was shown by successful sequencing of the contents of several peptide maps. A similar approach was recently applied to nanoelectrospray ionization (nanoESI) and nano‐liquid chromatography/tandem mass spectrometry (LC/MS/MS). The MALDI‐TOF/TOF technique allows for fast, direct sequencing of modified peptides in proteomics samples, and is complementary to the nanoESI and nanoLC/MS/MS approaches. Copyright © 2006 John Wiley & Sons, Ltd.
Detection of 17α‐hydroxyprogesterone caproate in equine plasma by gas chromatography/tandem mass spectrometry
Authors: McKinney Andrew R. , Suann Craig J. , Stenhouse Allen M. 
Published: May 2006

AbstractA method was developed for the analysis of the synthetic progestin 17α‐hydroxyprogesterone caproate in equine plasma following its administration by intramuscular injection. The method employed a reversed‐phase solid‐phase extraction followed by enol‐trimethylsilylation and analysis by gas chromatography/tandem mass spectrometry. The intact ester was detectable in the plasma for up to 2 weeks after a single therapeutic dose, and was found to be stable in equine whole blood for at least 2 months. Copyright © 2006 John Wiley & Sons, Ltd.
Real‐time depth‐mapping three‐dimension TV camera (Axi‐Vision camera)
Authors: Kawakita Masahiro , Iizuka Keigo , Iino Yoshiki , Kikuchi Hiroshi , Fujikake Hideo , Aida Tahito 
Published: May 2006

AbstractA three‐dimension camera (Axi‐Vision camera) has been developed that is capable of producing a color image of an object and performing high‐speed mapping of depth information from the camera to the object. With this camera, intensity‐modulated near‐infrared light is irradiated onto the object, and distances to points on the object are computed from the image captured by a camera that has a high‐speed shutter. Since a two‐dimensional scanning mechanism for a laser beam or complex computational processing is unnecessary in this depth mapping system, the distance to the object can be detected at high speed for each pixel of a TV image. For the present paper, a three‐dimension camera adapted to a standard television signal was constructed by development of a high‐output light‐emitting‐diode (LED) array light source capable of high‐speed intensity modulation, an image intensifier capable of high‐speed shutter operation on the nanosecond order, and an optical system. The prototype camera can output a depth image with a resolution of 768 × 493 pixels at a frame rate of 15 Hz, the characteristic depth mapping resolution of the camera is 1.8 cm (when the distance from the camera to the object is 2 m), and the camera can capture an image of a person‐sized object. It was also shown that the depth information thus obtained could be applied to live‐action filming and to CG and other new types of image synthesis. © 2006 Wiley Periodicals, Inc. Syst Comp Jpn, 37(8): 77–89, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20320
Multi‐subregion‐based probabilistic approach to pose‐invariant face recognition
Authors: Yamada Akihiko , Kanade Takeo 
Published: May 2006

AbstractCurrent automatic facial recognition systems are not robust to changes in illumination, pose, facial expression, and occlusion. In this paper, in order to address the problem of pose change, we propose an algorithm based on a probabilistic approach to face recognition that takes into account the pose difference between probe and gallery images. By using a large facial image database, the CMU PIE database, which contains images of the same set of people taken from many different angles, we have developed a probabilistic model of how facial features change as the pose changes. This model enables us to make our face recognition system more robust to changes of pose in the probe image. The experimental results show that this approach achieves a better recognition rate than conventional face recognition methods over a much larger range of poses. For example, when the gallery contains only images of a frontal face and the probe image varies its pose orientation, the recognition rate shows less than a 10% difference until the probe pose begins to differ by more than 45°, whereas the recognition rate of a PCA‐based method begins to drop at differences as small as 10°, and that of a representative commercial system begins to drop at 30°. © 2006 Wiley Periodicals, Inc. Syst Comp Jpn, 37(8): 68–76, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20437
3D information access space based on multifacet database visualization
Authors: Ohigashi Makoto , Tanaka Yuzuru 
Published: May 2006

AbstractIn order to access target information while getting an overview of the entirety of a large‐scale database, a search must be carried out in parallel with various modifications to the frame of reference and dynamic organization of the information. In this research, this type of database search is realized through an information access space dynamically constructed of hyperlinks based on an arbitrary frame of reference. The authors propose a new concept and structure for the frames of reference and develop a mechanism for dynamically linking individual database records with multiple information access spaces, dynamically constructed on the basis of declarative definitions of these frames of reference. The authors also provide a three‐dimensional interface for editing frames of reference and for spatial navigation threaded by these links. These operations correspond to query processing by narrowing down the subject tables and joining multiple tables; the user can gradually narrow his focus and arrive at the target information by dynamically modifying his frame of reference and repeating spatial movements. In this paper, a three‐dimensional interface is developed and database searches using that interface are evaluated; it is shown that this technique makes it possible to quickly access target information. © 2006 Wiley Periodicals, Inc. Syst Comp Jpn, 37(8): 13–23, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.20523
The influence of alkali‐degreasing on the chemical composition of hot‐dip galvanized steel surfaces
Authors: Berger Robert , Bexell Ulf , Stavlid Nils , Grehk T. Mikael 
Published: May 2006

AbstractThe influence of dipping temperature and time on the surface chemistry of hot‐dipped galvanized steel sheets during the alkaline degreasing process is investigated. The surface chemistry was monitored with scanning Auger electron spectroscopy (AES), X‐ray photoelectron spectroscopy (XPS), and time‐of‐flight secondary ion mass spectroscopy (ToF‐SIMS). The results show high Al concentrations on the untreated surfaces, which are significantly reduced during alkaline degreasing. The same conclusions could be drawn for the carbon compounds that accumulate on the surface during storage. The measurements reveal a gradual reduction in surface Al as the alkali solution temperature and/or degreasing time are increased. When degreasing was conducted at 70 °C for 30 s the surface was practically free from Al, which was present only in small islands. Furthermore, the experiments showed that the thickness of the oxide film covering the surfaces before and after alkaline degreasing is approximately 20 Å. The main constituents of the film varied from ZnAl hydroxide/oxide to Zn hydroxide/oxide, before and after degreasing, respectively. Copyright © 2006 John Wiley & Sons, Ltd.
Summary of ISO/TC201 technical report: ISO/TR 18392: 2005—Surface chemical analysis—X‐ray photoelectron spectroscopy—Procedures for determining backgrounds
Authors: Kövér L. 
Published: May 2006

AbstractISO Technical Report 18392 provides the guidance for determining backgrounds in X‐ray photoelectron spectra. The methods of background determination described in this report are applicable for the quantitative evaluation of the spectra of photoelectrons and Auger electrons excited by X‐rays from solid surfaces and surface nanostructures. Copyright © 2006 John Wiley & Sons, Ltd.