bluuebunny/crossref_metadata_2025_split huggingface dataset:
Matrix‐Free Formation of Gas‐Phase Biomolecular Ions by Soft Cluster‐Induced Desorption
Authors: Gebhardt Christoph. R. , Tomsic Anna , Schröder Hartmut , Dürr Michael , Kompa Karl L. 
Published: March 2009

AbstractWie Miniatur‐Schneebälle wirken neutrale Cluster aus einigen tausend Molekülen: Treffen sie mit ausreichender Geschwindigkeit auf eine Oberfläche, so können sie von dieser Biomoleküle wie Insulin ablösen. Weil die Cluster während und nach dem Aufprall auseinanderbrechen und verdampfen, stehen nach diesem mikroskopischen Schneeballwurf „nackte“ Biomolekülionen für massenspektrometrische Studien zur Verfügung.magnified image
Molekulare Erkennung in selbstorganisierten integrierten Schaltkreisen: kontrollierte Verkleinerung
Authors: Lim Yong‐beom , Lee Myongsoo 
Published: March 2009

AbstractIn Kleindruck erhältlich: Die Blockcopolymer‐Lithographie ermöglicht die Verkleinerung von integrierten Schaltkreisen – und das bei verkürzter Herstellungszeit. Eine auf Wasserstoffbrücken basierende Selbstorganisation durch molekulare Erkennung wurde genutzt, um auf der Oberfläche eines Siliciumsubstrats hochgeordnete quadratische Anordnungen von Blockcopolymeren zu erzeugen (siehe Bild).magnified image
Matrix‐Free Formation of Gas‐Phase Biomolecular Ions by Soft Cluster‐Induced Desorption
Authors: Gebhardt Christoph. R. , Tomsic Anna , Schröder Hartmut , Dürr Michael , Kompa Karl L. 
Published: March 2009

AbstractAll in a ball: Neutral molecular clusters consisting of a few thousand molecules can be seen as tiny snow balls; if they are thrown fast enough onto a surface, they are able to pick up biomolecules such as insulin from that surface. Since they break down and evaporate during and after the collision, bare biomolecular ions are available for mass spectrometry after such an energetic throw.magnified image
A Mechanism of Efficient G6PD Inhibition by a Molecular Clip
Authors: Kirsch Michael , Talbiersky Peter , Polkowska Jolanta , Bastkowski Frank , Schaller Torsten , de Groot Herbert , Klärner Frank‐Gerrit , Schrader Thomas 
Published: March 2009

AbstractTriple duty: A synthetic molecular clip traps nicotinamide adenine dinucleotide phosphate (NADP+; see picture) as well as occupying both the cofactor‐ and the substrate‐binding site in glucose‐6‐phosphate (G6P) dehydrogenase. This combination of two inhibition mechanisms makes the clip highly effective and selective for this enzyme over other dehydrogenases.magnified image
Phosphinoborane and Sulfidoborohydride as Chelating Ligands in Polyhydride Ruthenium Complexes: Agostic σ‐Borane versus Dihydroborate Coordination
Authors: Gloaguen Yann , Alcaraz Gilles , Pécharman Anne‐Frédérique , Clot Eric , Vendier Laure , Sabo‐Etienne Sylviane 
Published: March 2009

AbstractA question of coordination mode: Two new borane compounds are prepared. They act as bifunctional ligands as illustrated by their reaction with ruthenium polyhydrides which leads to the formation of two complexes (see scheme) displaying either a δ‐agostic interaction of a η2‐BH bond involving a trivalent boron atom or a dihydroborate ligation.magnified image
Asymmetric Suzuki–Miyaura Coupling in Water with a Chiral Palladium Catalyst Supported on an Amphiphilic Resin
Authors: Uozumi Yasuhiro , Matsuura Yutaka , Arakawa Takayasu , Yamada Yoichi M. A. 
Published: March 2009

AbstractYou oughta use water: Broad functional‐group (FG) tolerance was observed for the title coupling of aryl halides (X=Cl, Br, I) and aryl boronic acids to give biaryl compounds with up to 94 % ee. The chiral imidazoindole phosphine–palladium catalyst supported on an amphiphilic polystyrene–poly(ethylene glycol) (PS–PEG) resin could be recycled readily.magnified image
UV‐protecting and antibacterial finishing of cotton knits
Authors: Ibrahim N. A. , Gouda M. , Husseiny Sh. M. , El‐Gamal A. R. , Mahrous F. 
Published: March 2009

AbstractThis article deals with enhancing the UV‐protecting properties as well as the antibacterial activity of knitted cotton fabrics against two kinds of bacteria: gram‐positive bacteria (G +ve), i.e.,Staphylococcus aureus (S. aureus), and gram‐negative bacteria (G −ve), i.e.,Escherichia coli (E. coli). Results showed that the extent of improvement in the UPF values are determined by: the fabric structure, i.e., Interlock > Pique > Parasol, pretreatment history, i.e., gray > scoured > bleached, type of softening agent, incorporation of the UV‐absorber in the softening bath as well as sequence of addition, in addition to the nature of the deposited metal‐oxide, i.e., Cu > Zr > Zn ≫ Al ≈ none. On the other hand, the antibacterial activities of the treated substrates against G +ve and G −ve bacteria are outstandingly improved by using the proper: fabric structure, i.e., Parasol > Interlock > Pique, state of the untreated substrate, i.e., bleached > gray, finishing additives and regime, i.e., soft finishing (using polysiloxame softener—Adasil® SM) and UV‐protecting (using UV‐absorber, Tinofast® CEL) in one step > Tinofast® CEL‐finish > Adasil® SM‐finish > full‐bleaching, as well as deposited metal oxide, i.e., Zn > Cu > Zr > Al > none. Combined soft‐finishing and UV‐cutting as well asinsitu deposition of proper metal oxides, onto and/or within the knitted substrates, options exhibited both an excellent UV‐protection and prominent antibacterial activities. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Effect of clay surfactant type and clay content on the rheology and morphology of uncured fluoroelastomer/clay nanocomposites prepared by melt‐mixing
Authors: Lakshminarayanan Sriram , Lin Bin , Gelves Genaro A. , Sundararaj Uttandaraman 
Published: March 2009

AbstractFluoroelastomer/clay composites were prepared by melt mixing in an internal mixer using Cloisite® Nanoclays: NA, 15A, 20A, 30B, and 93A at three different concentrations viz. 2.5, 5.0, and 10.0 phr. Rheology, X‐ray diffraction (XRD), and transmission electron microscopy (TEM) were used to characterize the composites prepared. Dynamic rheological measurements showed significant increase in storage moduli (G′) in the terminal frequency region for the uncured composites prepared from Cloisite® 15A and 20A. At higher frequencies, organically modified nanoclays plasticize the polymer matrix leading to lower modulus values. Using all three characterization techniques, Cloisite® 15A and 20A were shown to have intercalated structure in the fluoroelastomer matrix, whereas other nanoclays were shown to have inferior dispersion. The storage modulus increases proportionally with increase in the clay loading and no clay aggregation was observed at higher loadings. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Recycled polypropylene reinforced with curaua fibers by extrusion
Authors: Spinacé Marcia A. Silva , Fermoseli Karen K. G. , De Paoli Marco‐A 
Published: March 2009

AbstractCuraua fibers were studied as reinforcing agents for postconsumer polypropylene. The composites were processed by extrusion. The composite properties were investigated by mechanical tests, thermal methods, melt flow index, surface morphology, and water uptake. The variables studied were as follows: fiber contents (10 to 40 wt %), fiber surface treatment, initial fiber length, and modification of the polypropylene matrix. The treatment of the fiber with 5 wt % NaOH aqueous solution did not improve fiber‐matrix adhesion and the composites using 20 wt % of untreated curaua fibers presented the better mechanical properties. Feeding the extruder with fibers having shorter lengths (0.01–0.4 mm) produced better fiber dispersion, improving the mechanical properties of the composites. Composites prepared using fibers without surface treatment with postconsumer polypropylene and with polypropylene modified with maleic anhydride showed mechanical properties and water uptake similar to composites using the same polymer reinforced with other lignocellulosic fibers. The extrusion process caused also partial fibrillation of the fibers, improving their aspect ratio. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
A simple approach to prepare PMA/TiO2 composite: The homogeneous dispersion of nano TiO2 in maleic anhydride polymer matrix
Authors: Hua Xiao , Bei Feng‐Li , Wang Xin 
Published: March 2009

AbstractThis contribution reports a simple approach for preparing PMA/TiO2 composite. In this method, nano TiO2 powders are previously treated by a combined modification process, namely, the alkali‐treatment followed by oleic acid surface‐grafting. Before polymerization, the modified TiO2 nanoparticles are dispersed into the maleic anhydride (MA) solution to form stable homogeneous gel. When the reaction temperature is raised to 150°C, the modified nano TiO2 can initiate the in situ anionic polymerization of MA. Finally, the PMA/TiO2 composites are obtained, in which all the TiO2 are fully coated by MA polymer (PMA). Therefore, it is not needed to reclaim the nano initiators because they are blended into the prepared polymers as the nano fillers. TEM and SEM experiment results can strongly demonstrate that the TiO2 nanoparticles are homogeneously dispersed in PMA matrix. This approach is easy‐to‐operate and applicable to the preparation of other nano composites. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Reactive phenylbenzimidazole UV absorbers and their application to cellulose textiles
Authors: Kubáč Lubomír , Akrman Jiří , Burgert Ladislav , Dvorský Drahomír , Grüner Pavel 
Published: March 2009

AbstractNew types of reactive UV absorbers for applications to cellulose textiles have been prepared. These substances are condensation products of sulfobenzimidazolaniline, cyanuric chloride, and aminophenyl‐(2‐sulfethoxy)‐sulfone. They were applied to bleached, unbleached, as well as dyed cellulose textiles with the aim to increase the protection effect of these textiles against UV radiation. All the tested textiles showed a marked increase in the UV protection factor (UPF). The effects of the UV absorbers tested neither interfere with the function of fluorescent brighteners (FBs) nor affect the hue of the used dyestuffs. They exhibit synergistic effect in the protection effectiveness against UV radiation: the UV absorbers used together with dyestuffs and FBs have a higher UPF factor than is the sum of UPF contributions of the individual components. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
The physical and mechanical properties of polyurethanes from oleic acid polyols
Authors: Velayutham T. S. , Abd Majid W. H. , Ahmad A. B. , Gan Yik Kang , Gan Seng Neon 
Published: March 2009

AbstractThree different polyester polyols, with various oleic acid content, were used in the preparation of polyurethane (PUR) coatings. The polyols were designated as Alk28, Alk40, and Alk65, in which 28, 40, and 65 represent the percentage of oleic acid of the polyol formulations. These polyester polyols were reacted with aromatic diisocyanate [toluene diisocyanate (TDI)] to form PUR coatings. The acid value, hydroxyl value, molecular weight, and viscosity of the polyols have been determined. The reaction between the polyols and TDI was studied by Fourier Transform Infrared spectroscopy and X‐ray diffraction (XRD). The effects of varying NCO/OH ratio and oleic acid content of polyols on physical and mechanical properties of PUR films were studied. XRD results indicate that the samples are amorphous. PURs, made with Alk28, have the best mechanical properties followed by Alk40 and Alk65. The mechanical properties of the samples have increased as the NCO/OH ratio was increased from 1.2 to 1.6. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Improved biocompatibility of parylene‐C films prepared by chemical vapor deposition and the subsequent plasma treatment
Authors: Song Jeom Sik , Lee Sukmin , Jung Seong Hee , Cha Gook Chan , Mun Mu Seong 
Published: March 2009

AbstractThe purpose of this study is to prepare the thin film of C‐type parylene (C‐type polyxylylene, parylene‐C) with improved biocompatibility for the biomedical applications, since in spite of the popularity, the parylene‐C has been known to have the less biocompatibility than the N‐type or D‐type parylene. To prepare the well‐designed parylene films through the chemical vapor deposition (CVD) process and the subsequent plasma surface treatment, the parameters of deposition and surface modification were controlled to obtain optimized physical and surface properties. Using CVD, the thin films of parylene‐C as thick as 5 μm were prepared under different deposition pressures. When increasing the deposition rate of parylene film or the deposition pressure, the tensile strength of film increased, whereas the properties such as the surface contact angle and permeability, and the elongation decreased. The deposition rate could be controlled to optimize the physical and physiochemical properties of films. The hydrophilicity of the parylene‐C film increased after plasma surface treatment by showing the larger water contact angle than untreated one. When the radio frequency power was above 100 W in the plasma process, the thin film obtained reveals an excellent cytotropism. It shows the improved biocompatibility with living cells. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis of highly improved Ziegler‐Natta catalyst
Authors: Monji Majid , Pourmahdian Saeed , Vatankhah Mohammad , Taromi Faramarz Afshar 
Published: March 2009

AbstractThe effects of media viscosity, mixing speed, and injection time on catalyst average particle size (APS), particle size distribution (PSD), and morphology in both conditions, with and without emulsifier, were investigated. Supports were prepared using a so‐called recrystallization method; then they were catalyzed under the same condition. To show the effects of emulsifier on the final product's properties such as catalyst activity, polymer isotacticity, and so on, two types of catalysts were polymerized and finally their results were compared. Scanning electron microscopy micrographs were used for morphological study. Results show that by increasing the media viscosity and injection time, APS of the catalyst support was decreased. But by increasing the mixing speed, APS was decreased and PSD was broadened. It was found that emulsifier reduces the sensitivity of APS and PSD of catalyst when the support preparation conditions are changed. Consequently, by employing emulsifier, highly improved catalyst was produced. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Crystallization behavior of fully biodegradable poly(lactic acid)/poly(butylene adipate‐co‐terephthalate) blends
Authors: Xiao Hanwen , Lu Wei , Yeh Jen‐Taut 
Published: March 2009

AbstractBoth poly(lactic acid) (PLA) and poly(butylene adipate‐co‐terephthalate) (PBAT) are fully biodegradable polyesters. The disadvantages of poor mechanical properties of PLA limit its wide application. Fully biodegradable polymer blends were prepared by blending PLA with PBAT. Crystallization behavior of neat and blended PLA was investigated by differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and wide angle X‐ray diffraction (WAXD). Experiment results indicated that in comparison with neat PLA, the degree of crystallinity of PLA in various blends all markedly was increased, and the crystallization mechanism almost did not change. The equilibrium melting point of PLA initially decreased with the increase of PBAT content and then increased when PBAT content in the blends was 60 wt % compared to neat PLA. In the case of the isothermal crystallization of neat PLA and its blends at the temperature range of 123–142°C, neat PLA and its blends exhibited bell shape curves for the growth rates, and the maximum crystallization rate of neat PLA and its blends all depended on crystallization temperature and their component. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Electropolymerization of o‐phenylenediamine on Pt‐electrode from aqueous acidic solution: Kinetic, mechanism, electrochemical studies and characterization of the polymer obtained
Authors: Sayyah S. M. , El‐Deeb M. M. , Kamal S. M. , Azooz R. E. 
Published: March 2009

AbstractElectropolymerization of O‐phenylenediamine (o‐PD) on Pt‐electrode from a deoxygenated aqueous acid medium was carried out using cyclic voltammetry technique. The kinetic parameters were calculated by means of electrochemical data. The experimentally obtained kinetic equation was RP,E = kE [monomer]1.19 [acid]1.23 [electrolyte]0.87 from the value of the anodic current density using cyclic voltammetry technique. The apparent activation energy (Ea) is found to be 28.34 kJ mol−1. The polymer films obtained have been characterized by X‐ray diffraction, elemental analysis, scanning electron microscopy, 1H‐NMR, 13C‐NMR, UV‐visible, and IR spectroscopy. The mechanism of the electrochemical polymerization reaction has been discussed. TGA is used to confirm the proposed structure and determination of the number of water molecules in the polymeric chain unit. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation and characterization of collagen‐based composite conduit for peripheral nerve regeneration
Authors: Xiangmei Wang , Jing Zhang , Hao Chen , Qingrui Wang 
Published: March 2009

AbstractCollagen‐based composite nerve conduit scaffold was prepared by freeze‐drying steam‐extrusion method and modified chemically with glutaraldehyde (GTA) by adding chitosan into collagen. Fourier transform infrared spectroscopy showed that the collagen and chitosan are certainly crosslinked through GTA. It was observed under scanning electron microscope that the modified nerve conduit material is a porous three‐dimensional crosslinked structure and the quantity ratio of the collagen to chitosan has influence on the morphology. The cell proliferation experiment results showed that the collagen‐based composite scaffold prompts the adhesion and proliferation of cells, but as the chitosan increasing, the cell proliferation decreased slightly. The swelling property, the collagenase degradation, and the mechanical property of the scaffold are tested at the quantity ratios of collagen to chitosan 4 : 3, 3 : 1, and 4 : 1 and crosslinking time 0.5 and 1.0 h. The experiments show that the stability of the scaffold is enhanced with decreasing the quantity ratio of collagen to chitosan and increasing crosslinking time. Through the experimental investigations, the modifying technique parameters are discussed and the scaffold exhibits better physical and chemical properties at the quantity ratio of collagen to chitosan 3 : 1 and crosslinking time 0.5 h. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Poly(vinyl alcohol) nanocomposites with sepiolite and heat‐treated sepiolites
Authors: Alkan M. , Benlikaya R. 
Published: March 2009

AbstractPoly(vinyl alcohol) (PVA) nanocomposites with pristine sepiolite and heat‐treated (HT) sepiolites were prepared by the method of solution dispersion. The measurements of XRD, FTIR, TEM, and AFM were used for the characterization of the nanocomposites. Furthermore, thermal and optical properties were investigated by TG/DTG/DTA and UV‐visible transmission spectra, respectively. Both the effects of sepiolite/polymer ratio and the structural changes in sepiolite on heating were examined in terms of changes in the properties of the nanocomposites. The addition of sepiolite/HT sepiolites into the PVA matrix resulted in a decrease in the thermal decomposition temperatures of the nanocomposites because of the fact that sepiolite and HT sepiolites facilitated the elimination of the water and acetate groups from the PVA in the second step based on the TG/DTG studies. The HT sepiolites‐PVA nanocomposites had lower thermal stability and more influenced optical clarity than those of the sepiolite PVA, at the same filler levels. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Studying the degradation of polyhydroxybutyrate‐co‐valerate during processing with clay‐based nanofillers
Authors: Cabedo Luis , Plackett David , Giménez Enrique , Lagarón José María 
Published: March 2009

AbstractPolyhydroxybutyrate‐co‐valerate (PHBV) is attracting interest as a new material for packaging applications and nanoparticulate layered silicates are being increasingly explored as a way to improve PHBV film properties. In this context, it is essential to understand how different types of nanofillers could influence polymer properties. PHBV was processed with three‐layered clay types using different mixing methods, and we examined the effect of processing time, clay type, and clay content on polymer molecular weight and composite morphology. PHBV molecular weight (Mw) decreased by 38% after extrusion processing and was further reduced in the presence of montmorillonite (MMT). However, when PHBV was processed with kaolinite as the additive, no further reduction in polymer molecular weight was observed. Molecular weight also decreased as the MMT clay content increased from 1 to 5 wt %. The results suggest that release of tightly bound water from clay surfaces at elevated temperature may be responsible for PHBV degradation during processing. Evidence also points to the possibility that the surface modifier present in organically modified MMT may catalyze PHBV degradation in some way. X‐ray diffraction studies indicated an intercalated morphology in the presence of modified montmorillonite but good dispersion was also achieved when unmodified kaolinite was blended with PHBV. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
The multilayered nature of reference selection
Authors: Camacho‐Miñano María‐del‐Mar , Núñez‐Nickel Manuel 
Published: March 2009

AbstractWhy authors choose some references in preference to others is a question that is still not wholly answered despite its being of interest to scientists. The relevance of references is twofold: They are a mechanism for tracing the evolution of science, and because they enhance the image of the cited authors, citations are a widely known and used indicator of scientific endeavor. Following an extensive review of the literature, we selected all papers that seek to answer the central question and demonstrate that the existing theories are not sufficient: Neither citation nor indicator theory provides a complete and convincing answer. Some perspectives in this arena remain, which are isolated from the core literature. The purpose of this article is to offer a fresh perspective on a 30‐year‐old problem by extending the context of the discussion. We suggest reviving the discussion about citation theories with a new perspective, that of the readers, by layers or phases, in the final choice of references, allowing for a new classification in which any paper, to date, could be included.
A bibliometric evaluation of research performance in different subject categories
Authors: Nah In Wook , Kang Dai‐Shin , Lee Dae‐Hee , Chung Yun‐Chul 
Published: March 2009

AbstractIn this article, bibliometric indicators with publications and citations are used for a direct research‐performance comparison among different or interdisciplinary categories, the work of individual scientists, and their research teams and institutions. For example, basic research performances of some projects at the Korea Institute of Science and Technology (KIST) were assessed using bibliographic factors with IPQ‐Normalized impact factor to compare with an international level and other research groups in different or interdisciplinary fields. Some research teams at KIST showed higher quality publications in terms of the international measures.
Score‐based bibliometric rankings of authors
Authors: Marchant Thierry 
Published: March 2009

AbstractScoring rules (or score‐based rankings or summation‐based rankings) form a family of bibliometric rankings of authors such that authors are ranked according to the sum over all their publications of some partial scores. Many of these rankings are widely used (e.g., number of publications, weighted or not by the impact factor, by the number of authors, or by the number of citations). We present an axiomatic analysis of the family of all scoring rules and of some particular cases within this family.