bluuebunny/crossref_metadata_2025_split huggingface dataset:
Prevalence of auditory changes in newborns in a teaching hospital
Authors: Barbosa Maria Alves , Guimarães Valeriana de Castro 
Published: May 2012

Summary
Introduction: The precocious diagnosis and the intervention in the deafness are of basic importance in the infantile development. The loss auditory and more prevalent than other joined riots to the birth.
Objective: Esteem the prevalence of auditory alterations in just-born in a hospital school.
Method: Prospective transversal study that evaluated 226 just-been born, been born in a public hospital, between May of 2008 the May of 2009.
Results: Of the 226 screened, 46 (20.4%) had presented absence of emissions, having been directed for the second emission. Of the 26 (56.5%) children who had appeared in the retest, 8 (30.8%) had remained with absence and had been directed to the Otolaryngologist. Five (55.5%) had appeared and had been examined by the doctor. Of these, 3 (75.0%) had presented normal otoscopy, being directed for evaluation of the Evoked Potential Auditory of Brainstem (PEATE). Of the total of studied children, 198 (87.6%) had had presence of emissions in one of the tests and, 2 (0.9%) with deafness diagnosis.
Conclusion: The prevalence of auditory alterations in the studied population was of 0,9%. The study it offers given excellent epidemiologists and it presents the first report on the subject, supplying resulted preliminary future implantation and development of a program of neonatal auditory selection.
Nanocomposite preparation by thermal decomposition of [Ag(hfac)(COD)] in amorphous polystyrene
Authors: Carotenuto G. , Palomba M. , Nicolais L. 
Published: May 2012

AbstractA simple technique to prepare plastic color filters based on the surface plasmon resonance of silver nanoparticles has been developed. In particular, silver/polystyrene nanocomposite has been prepared by dissolving silver 1,5‐cyclooctadiene‐hexafluoroacetylacetonate in amorphous polystyrene, and the obtained solid solution was heated for ca. 10 s at a convenient temperature (180°C). In these conditions, the metal precursor decomposes and produces silver atoms that diffuse into the polymeric matrix and clusterize, leading to the formation of a contact‐free dispersion of silver nanoparticles. The resulting films have been characterized by large‐angle X‐ray powder diffraction, transmission electron microscopy, and UV–vis spectroscopy. © 2012 Wiley Periodicals, Inc. Adv Polym Techn 31: 242–245, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21278
PROCESSING THERMOPLASTIC MATRIX TOWPREGS BY PULTRUSION
Authors: Nunes J. P. , Silva J. F. , Novo P. J. 
Published: May 2012

AbstractIn the work reported herein, glass fiber reinforced polypropylene towpregs, produced continuously at different processing conditions in a dry powder coating equipment (towpregger), were processed into final composite parts in a specially developed prototype pultrusion equipment. The influence of the towpregger fiber pull speed and the furnace temperature on the polymer content of the final towpregs was determined. The towpregs' quality was also assessed using optical microscopy and scanning electron microscopy. They were then processed into composite profiles in the pultrusion machine, and the influence of the pull speed and dies' temperatures on their mechanical and other relevant physical properties was studied. Finally, the best processing window and the optimization of the final composite profiles are discussed. © 2012 Wiley Periodicals, Inc. Adv Polym Techn 32: E306–E312, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/adv.21279
Nasal septal deviation in a mediaeval population
Authors: Mays Simon 
Published: May 2012

AbstractIn modern populations, there is evidence that nasal septal deviation (NSD) may be associated with maxillary sinusitis, and that those with NSD may differ in craniofacial morphology from those without or with less severe NSD. Whether these associations hold true for earlier populations has yet to be investigated. The current work is a step toward remedying this. The study group comes from a mediaeval English archaeological site. NSD was quantified using image analysis. Maxillary sinusitis was identified from new bone formation in the antrum. Cranial morphology was assessed using standard craniometric measurements. The results provided no evidence for a relationship between NSD and maxillary sinus disease. NSD was associated with reduced measures of upper facial height, suggesting decoupling of growth in vertical height of the nasal septum and the bony structures surrounding it. Am J Phys Anthropol 148:319–326, 2012. © 2012 Wiley Periodicals, Inc.
Curcumin – vom Molekül zur biologischen Wirkung
Authors: Esatbeyoglu Tuba , Huebbe Patricia , Ernst Insa M. A. , Chin Dawn , Wagner Anika E. , Rimbach Gerald 
Published: May 2012

AbstractCurcuma (Gelbwurzel) wird traditionell als Würzmittel für Lebensmittel eingesetzt. Curcumin ist ein wichtiger Bestandteil des Currypulvers und verleiht dem Pulver seine charakteristische Farbe. Aufgrund seiner intensiven gelben Farbe wird Curcuma bzw. Curcumin (Zusatzstoff E100) auch zum Färben von Lebensmitteln (z. B. Senf) verwendet. Curcuma enthält die Curcuminoide Curcumin, Demethoxycurcumin und Bisdemethoxycurcumin. In jüngster Zeit werden vermehrt gesundheitsfördernde Eigenschaften (Neuroprotektion, Chemo‐ bzw. Krebsprävention) von Curcuminoiden diskutiert. Curcuminoide induzieren im Organismus endogene antioxidative Schutzsysteme und wirken entzündungshemmend. Curcuminoide beeinflussen die Genexpression sowie epigenetische Regulationsmechanismen. Synthetische Curcumin‐Analoga zeigen zum Teil biologische Wirkungen. Dieser Aufsatz beschreibt die Entwicklung von Curcuma vom “traditionellen” Würz‐ und Färbemittel zum “modernen” biologischen Regulator.
Hydrogen‐Abstraction Reactivity Patterns from A to Y: The Valence Bond Way
Authors: Lai Wenzhen , Li Chunsen , Chen Hui , Shaik Sason 
Published: May 2012

Abstract“Give us insight, not numbers” was Coulson’s admonition to theoretical chemists. This Review shows that the valence bond (VB)‐model provides insights and some good numbers for one of the fundamental reactions in nature, the hydrogen‐atom transfer (HAT). The VB model is applied to over 50 reactions from the simplest H + H2 process, to P450 hydroxylations and H‐transfers among closed‐shell molecules; for each system the barriers are estimated from raw data. The model creates a bridge to the Marcus equation and shows that H‐atom abstraction by a closed‐shell molecule requires a higher barrier owing to the additional promotion energy needed to prepare the abstractor for H‐abstraction. Under certain conditions, a closed‐shell abstractor can bypass this penalty through a proton‐coupled electron transfer (PCET) mechanism. The VB model links the HAT and PCET mechanisms conceptually and shows the consequences that this linking has for H‐abstraction reactivity.
Importance of pressure drop in divided wall distillation column
Authors: Sangal Vikas Kumar , Bichalu L. , Kumar Vineet , Mishra Indra Mani 
Published: May 2012

ABSTRACTPressure drop calculations are extensively used for finding tray spacing at the time of designing a column, but these are rarely performed for the simulation purposes as a minor change in pressure (from condenser to reboiler) has insignificant effect on the vapour–liquid equilibrium. However, pressure difference plays an important role in deciding vapour and liquid flow rate across a tray (or trays), particularly in case of interconnected or divided wall distillation column (DWC). In case of a DWC, the feasible vapour split ratio below the divided wall section is naturally adjusted in such a way that the pressure drops in the two parallel branches of the DWC are equal. In the present work, simulation of a DWC using the MultiFrac model of aspen plusTM (Aspen Technology, Inc., Burlington, MA, USA) was carried out to study the feasible vapour split as a function of reflux ratio and liquid split ratio. The results are interesting in that they show a little effect of liquid split ratio on the feasible vapour split ratio and significantly different pressure profiles in two sides of the DWC. It was also found that the variation in vapour flow rate leads to a large variation in the concentration profile. These results indicate that the pressure drop may be one of the key parameters that should be considered for the optimal design and control of a DWC. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.
Comparison of the effects of wettability alteration and IFT reduction on oil recovery in carbonate reservoirs
Authors: Sheng James J. 
Published: May 2012

ABSTRACTInjection of chemicals in a carbonate reservoir may change wettability and reduce interfacial tension (IFT). The question is how much each mechanism contributes to the increase in oil recovery. There is lack of such information in the literature. The information is very important because it will guide us to select which chemicals to use, as some chemicals can effectively reduce IFT, whereas others can change wettability.This paper aims to compare the effects of different mechanisms in oil recovery related to chemical enhanced oil recovery (EOR) . Particularly, we compare the effects of wettability alteration and IFT reduction. Numerical simulation models are used. Our results show that wettability alteration plays important roles when IFT is high, and it is effective in the early time. IFT plays very important roles with or without wettability alteration and is effective during the entire process. Note that the matrix permeability is reasonably high so that the fluids can be redistributed. The implication is that anionic surfactants are preferred to cationic surfactants in chemical EOR, as the former are generally used to reduce IFT, whereas the latter are used to change wettability. Other observations are that in surfactant‐induced wettability alteration with low IFT, gravity drive is a very important mechanism. Molecular diffusion of chemicals affects oil recovery rate in the early time, but not ultimate oil recovery. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.
Kinetics of photocatalytic degradation of atrazine on molecularly imprinted titania film
Authors: Zhang Chunjing , Yang Zhengpeng , Zhang Chunxiao , Sun Yukun 
Published: May 2012

ABSTRACTA titania film imprinted by atrazine molecule at the surface of a quartz crystal was prepared using molecular imprinting and surface sol–gel process. The quartz crystal microbalance technique was employed to in situ investigate the degradation behavior of atrazine on the molecularly imprinted titania film. The obtained results reveal that the molecular imprinting can enhance degradation of atrazine on titania films, and the degradation rate constants (K) estimated from the in situ frequency measurement is about 0.62 × 10−3 s−1, which is two times higher than that obtained on non‐imprinted titania films. © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.
Preparation of photocured azidophenyl‐fish gelatin and its capturing of human epidermal growth factor on titanium plate
Authors: Park Shin‐Hye , Seo Si‐Yoong , Kang Jeong‐Hwa , Ito Yoshihiro , Son Tae‐Il 
Published: May 2012

AbstractProtein immobilization is important in various medical fields that involve the use of metal. Titanium has been often utilized in various medical fields based on its biocompatibility and noncytotoxicity. However, as an unmodified titanium surface is not suitable, dopamine must be coated on the titanium surface. Among gelatin sources, fish gelatin is more suitable in the human body and does not pose serious side effects compared to porcine gelatin. Therefore, a photoreactive azidophenyl group was introduced to fish gelatin to create azidophenyl‐fish gelatin (azidophenyl‐f.gel). The azidophenyl group was analyzed by 1H‐NMR, UV spectroscopy, and gel permeation chromatography. The curing ratio of azidophenyl‐f.gel was measured using a micropatterning plate. Epidermal growth factor immobilization ability, cytotoxicity, and cell attachment tests were performed. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Effect of seed characteristics on morphology development in poly(n‐butyl acrylate)‐poly(n‐butyl methacrylate) core‐shell dispersions
Authors: Suresh Kattimuttathu I. , Bartsch Eckhard 
Published: May 2012

AbstractThis article reports on the influence of synthesis characteristics such as seed cross linking, particle‐size distribution (PSD), and surfactant in the seeded emulsion polymerization of n‐butyl acrylate–butyl methacrylate core‐shell systems. These systems were studied using a combination of techniques such as light scattering (static and dynamic), asymmetric field flow fractionation coupled with multiangle laser light scattering and transmission electron microscopy. Complimentary data, obtained from static light scattering and electron microscopy studies, on the effect of seed crosslinking on morphology development reveals that the presence of a crosslinked seed favors the formation of nonequilibrium core‐shell morphology. For uncrosslinked seeds occluded structures were present with a diffuse boundary between the core and the shell. In both cases, i.e., with or without surfactant, a monomodal PSD was observed for the core‐shell systems and the relative size polydispersity and the shape of the seed PSD were retained. Use of surfactant was found to broaden the PSD but did not seem to affect the formation core‐shell morphology. The study also shows the influence of crosslinked seeds on the film properties. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Compatibilization of natural rubber/high density polyethylene thermoplastic vulcanizate with graphene oxide through ultrasonically assisted latex mixing
Authors: Yan Ning , Xia Hesheng , Wu Jinkui , Zhan Yanhu , Fei Guoxia , Chen Chen 
Published: May 2012

AbstractNatural rubber (NR)/high density polyethylene (HDPE) thermoplastic vulcanizate was compatibilized with graphene oxide (GO) by an ultrasonically assisted latex mixing process (ULM). GO was dispersed into NR latex by ultrasonic irradiation and followed by latex coagulation to obtain the NR/GO master‐batch, which was further mixed and diluted with HDPE and NR via a dynamic vulcanization process to obtain the NR/HDPE/GO hybrid composites. It was found that the stacked GO platelets were successfully exfoliated by the ULM process and have good compatibilization efficiency for the immiscible NR and HDPE. A smaller discrete NR domain was observed in NR/HDPE blend in the presence of the GO. Moreover, the stacked GO platelets enhance the interfacial adhesion and phase compatibility, which results in an increase in mechanical property of NR/HDPE blends. Compared to the NR/HDPE blend, the tensile strength and tensile modulus at 300% strain for NR/HDPE/ (1.5 phr) GO blend were increased by ∼ 27% and ∼ 24%, respectively. The exfoliated GO can act as both the effective reinforcing filler and compatibilizer in the immiscible NR/HDPE blend. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Properties of polyimide hybrids with mixed metal oxide
Authors: Lu Hsu‐Tung , Huang Shih‐Liang , Tseng I‐Hsiang , Lin Yin‐Kai , Tsai Mei‐Hui 
Published: May 2012

AbstractPolyimide/silica–titania (PI/SiO2–TiO2) hybrid films were prepared via an in situ sol–gel process. The PI precursor, poly(amic acid) (PAA), which contains 2,2'‐bis[4‐(4‐aminophenoxy)‐phenyl]propane (p‐BAPPP), 3,3',4,4'‐ benzophenetetracarboxylic anhydride (BTDA) and 3‐aminopropyltrimethoxysilane (APrTMOS), was first synthesized; this was followed by the addition of phenyltrimethoxysilane (PTMS) and/or tetraethyl orthotitanate (Ti(OEt)4) to fabricate PI/SiO2–TiO2 films. The relative content of SiO2 to TiO2 has remarkable effects on the crosslink structure and resultant properties of the hybrids. XPS results confirm that the amount of Si on the surface of the hybrids is higher than that in the bulk. The distribution of Ti in the hybrid films is contrary to the above trend because of the formation of three‐dimensional SiOSi, SiOTi, and TiOTi networks. The SiO2 content of the hybrids containing only silica significantly affects their refractive index, contact angle, and dielectric constant. The films with added PTMS show higher contact angles than pure PI because nonpolar segments, C2H6 or benzene groups, tend to distribute on the surface. Upon the addition of (Ti(OEt)4), some hydrophilic segments on the surface of the hybrids are induced because of the formation of a crosslinked structure. The denser crosslinked molecular structure, and consequently lower CTE and higher Tg are obtained from hybrids containing more TiO2. By comparing the above properties and flexibility, the best composition of metal oxides (SiO2/TiO2) in hybrids is 20/80. That is, an optimum ratio of metal oxides in PI hybrids induces superior properties for advanced practical applications. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Side effects in the application of polyamide 6 barrier materials for fuel tanks
Authors: Chernev Boril S. , Eder Gabriele C. 
Published: May 2012

AbstractTo reduce the pollution of air by minimizing evaporative emissions from fuel tanks, new plastic fuel tanks made of materials with excellent barrier properties have to be developed. Single‐layer polyamide 6 tanks are one option to meet the requested low‐hydrocarbon permeation rates for motorcycle vehicle tanks. Recently, some problems with respect to deposits in polyamide 6 tanks, blocked nozzles, tubing, and gasoline filters were observed. Thus, samples (precipitates) were taken from unused tanks after conditioning as well as of used tanks and filters after being in contact with gasoline for some time. By investigating the precipitates and deposits by means of infrared (IR) spectroscopy, the main constituents were identified to be cyclic caprolactam oligomers. Additional investigations on the extracted samples by mass spectroscopy allowed us to attribute specific features of the IR spectra to the individual cyclic oligomers (dimer, trimer, and tetramer). In addition, we could show that the crystalline precipitates and deposits in the fuel systems of used vehicles consist of mixtures of the cyclic dimer, trimer, tetramer, and even pentamer of caprolactam with varying contributions of the individual oligomers in dependence of the history of the part. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
POMA/PMMA blends modified by dye: Spectroscopic and morphological properties
Authors: Pereira N. S. , do Monte A. F. G. , Ceschin A. M. , Sales M. J. A. 
Published: May 2012

AbstractPoly(o‐methoxyaniline) (POMA), a conductive polymer (CP) well known, was used to prepare blends with poly(methyl methacrylate) (PMMA). Conducting polymer keeps absorbance strength within the PMMA matrix. POMA/PMMA blends presented absorption bands regarding the conducting polymer with different intensities and the main band red shifting. However, POMA/PMMA blends showed no photoluminescence (PL) emission. After the hybridization process of the CP with a photoluminescent dye, 2,1,3‐benzothiadiazole, POMA/PMMA blends showed new optical properties. PL spectra revealed an emission in the range of 500–550 nm, indicating interaction between the dye and the conducting polymer. The presence of the dye modified the morphological properties of the POMA/PMMA blends. New features have appeared on the surface of the blends prepared with higher concentration of hybridized CP. Blends with lower concentrations of hybridized CP showed their surfaces with POMA globules being covered by PMMA. This morphology replaced the globules and “crystals” on the surface of the blends prepared without the dye. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Nucleation effect of hydroxyl‐purified multiwalled carbon nanotubes in poly(p‐phenylene sulfide) composites
Authors: Sheng‐Ling Jiang , Xiao‐Yu Gu , Zhi‐Yuan Zhang 
Published: May 2012

AbstractTo investigate the nucleation effect of hydroxyl‐purified multiwalled carbon nanotubes (MWNTs‐OH) in poly(p‐phenylenesulfide) (PPS), a series of composites were prepared by blending PPS with MWNTs‐OH at 1, 2, and 3 wt %, respectively. Under SEM observation MWNTs‐OH were found homogeneously dispersed in the PPS matrix. DSC thermograms revealed that the enthalpy (ΔHc) of the composites increased with increasing MWNT‐OH content, whereas the crystallization temperature (Tc) decreased progressively. The decrease in Tc was in accordance with the smaller crystallite size determined with WXRD characterization, and the increase in ΔHc was evidenced by FTIR and XPS analyses. The higher ΔHc shows that MWNTs‐OH serves as a nucleating agent, providing sufficiently multiplied sites for crystal growth. The lowering of Tc was attributed not only to MWNTs‐OH network hindrance to PPS chain fusing rearrangement, but also to a poorer affinity between MWNTs‐OH and PPS; both effects coordinately govern Tc of PPS/MWNTs‐OH composites. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
A new insight into interface widths in binary polymer blends based on ortho‐positronium lifetime studies
Authors: Ramya P. , Ranganathaiah C. 
Published: May 2012

AbstractThe interface widths in two immiscible polymer blend (Poly vinyl chloride (PVC)/Polystyrene (PS)) and PVC/Ethylene Vinyl Acetate (EVA) are determined experimentally using hydrodynamic interaction approach through free volume measurement by positron annihilation lifetime spectroscopy. For comparison, the same study is performed in a miscible blend (Styrene Acrylonitrile (SAN)/Poly Methyl Methacrylate (PMMA)). The interfacial width (Δl) is evaluated from the hydrodynamic interaction (α) based on Kirkwood–Risemann theory and friction coefficient from Stokes equation. Friction at the interface of a binary blend evidences how close the surfaces of the polymer chains come or stay apart which in turn depends on the type of force/interaction at the interface. In this work, we define interface width from a different perspective of Flory–Huggins interaction approach. Measured composition dependent interface widths in the three blends studied clearly demonstrate the sensitivity of the present method. In miscible blend, high friction at the interface results in stronger hydrodynamic interaction and hence smaller interface widths (0.36–1.97 Å), whereas weak or no interaction in immiscible blends produce wider widths (2.81–25.0 Å). © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Mechanical and thermal degradation properties of silk from African wild silkmoths
Authors: Teshome Addis , Onyari John M. , Raina Suresh K. , Kabaru Jacques M. , Vollrath Fritz 
Published: May 2012

AbstractVariations among silk of four African wild silkmoths,Argema mimosae,Anaphe panda,Gonometa postica, andEpiphora bauhiniae, was studied regarding their mechanical properties and thermal degradation behaviors. Cocoon shells and individual degummed fibers were examined using tensile testing, thermogravimetric analysis, and scanning electron microscope (SEM).A. mimosaeandG. posticacocoon shells had marginally higher initial moduli and strains at maximum stress. The stress–strain curves ofBobmyx moriandA. pandadegummed fibers lacked clear yielding points.G. posticafibers had the highest breaking energy (76.4 J/cm3) and breaking strain (41.3%). The ultimate tensile strength was the highest forB. mori(427 MPa). Fiber pull‐out and detachment was predominant in fracture surfaces of both the cocoon shells and the fibers. Wild cocoon shells and degummed fibers had higher temperature for dehydration loss thanB. mori.A. mimosaefibers (11.9%) and G. postica cocoon shells (13.3 %) had the highest weight loss due to dehydration.E. bauhinaecocoon shells andB. morifibers had the highest total weight losses of 97.2 and 93.4%, respectively. The African silks exhibited variations in their mechanical and thermal degradation properties related to their physical and chemical structure and composition. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013