bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterisation and Quantification of Flavonoids in Iris germanica L. and Iris pallida Lam. Resinoids from Morocco
Authors: Roger B. , Jeannot V. , Fernandez X. , Cerantola S. , Chahboun J. 
Published: December 2011

ABSTRACTIntroductionIris resinoid obtained from Iris germanica or Iris pallida rhizomes is widely used in the perfume industry but its chemical composition has not yet been reported. Nevertheless, very active compounds have been identified in iris rhizomes including iridals and isoflavones.ObjectiveIn this first study concerning iris resinoid composition, flavonoids were qualitatively and quantitatively investigated in I. germanica and I. pallida resinoids.MethodologyResinoids were first fractionated by reverse‐phase flash chromatography in order to obtain fractions containing all isoflavones. These fractions were analysed by HPLC‐DAD (diode array detector) and the fractions containing isoflavones were analysed by HPLC‐QTOF (quadrupole time of flight)‐MS. Then, the main isoflavones were isolated and identified by NMR and high‐resolution mass spectroscopy (HRMS). Finally, total and individual isoflavones were quantified by HPLC‐DAD at 265 nm using an external calibration method with irigenin as the external standard.ResultsEight isoflavones were identified in both resinoids (irigenin, iristectorigenin A, nigricin, nigricanin, irisflorentin, iriskumaonin methyl ether, irilone, iriflogenin), one isoflavone only was identified in I. germanica resinoid (irisolidone), whereas one isoflavone (8‐hydroxyirigenin), one isoflavanone (2,3‐dihydroirigenin) and one benzophenone (2,6,4′‐trihydroxy‐4‐methoxybenzophenone) only were identified in I. pallida resinoid. Isoflavones were quantified in I. germanica and I. pallida resinoids at 180 ± 1.6 mg/g and 120 ± 3.3 mg/g respectively.ConclusionThe study shows that I. germanica and I. pallida resinoids are rich in flavonoids and that these two Iris species can be distinguished by simply analysing the polyphenol fraction. Copyright © 2011 John Wiley & Sons, Ltd.
Effect of maleic anhydride grafted polybutadiene on the compatibility of polyamide 66/acrylonitrile‐butadiene‐styrene copolymer blend
Authors: Yang Huahao , Cao Xinyu , Ma Yongmei , An Jingjing , Ke Yucai , Liu Xiaoming , Wang Fosong 
Published: December 2011

AbstractThe addition of maleic anhydride grafted polybutadiene (PB‐g‐MAH) can greatly improve the compatibility of polyamide 66 (PA66)/acrylonitrile‐butadiene‐styrene copolymer (ABS) blends. Unlike the commonly used compatibilizers in polyamide/ABS blends, PB‐g‐MAH is compatible with the ABS particles' core phase polybutadiene (PB), rather than the shell styrene‐acrylonitrile (SAN). The compatibility and interaction of the components in the blends were characterized by Fourier transform‐infrared spectra (FTIR), Molau tests, melt flow index (MFI), dynamic mechanical analyses (DMA), and scanning electron microscopic (SEM) observations. The results show that PB‐g‐MAH can react with the amino end groups in PA66 while entangle with the PB phase in ABS. In this way, the compatibilizer anchors at the interface of PA66/ABS blend. The morphology study of the fracture sections before and after tensile test reveals that the ABS particles were dispersed uniformly in the PA66 matrix and the interfacial adhesion between PA66 and ABS was increased significantly. The mechanical properties of the blends thus were enhanced with the improving of the compatibility. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Characterization and performance of PVA/Psf composite hollow fiber UF membrane prepared with interfacial polymerization
Authors: Peng Yuelian , Han Hua , Fan HongWei 
Published: December 2011

AbstractA new composite hollow fiber ultrafiltration (UF) membrane was prepared with the interfacial polymerization method. A dense layer of polyvinyl alcohol (PVA) was coated on the surface and embedded into the pores of the support polysulfone (PSf) membrane through a dead‐end filtration process and cross‐linked reaction with diisocyanate (TDI) at room temperature. The surface morphology and functional groups of the composite membrane were characterized by atomic force microscopy (AFM), scanning electron microscopy (SEM), and Fourier transformation infrared spectrometer (FTIR). Anti‐fouling experiments were conducted to study the hydrophilicity and anti‐fouling properties of the support and composite membranes. The performances of the composite membrane were significantly influenced by preparation conditions. The composite membrane that performed most efficiently was prepared at an optimal condition: 30 min of dead‐end filtration, 0.25 wt% of PVA, 0.50 vol% of TDI, and 60 sec of interfacial reaction. Laboratory scale tests demonstrated that the new composite PVA/PSf membrane has a higher anti‐fouling capability and higher flux for oily wastewater treatment. The hydrophilic groups (OH) enriched in the PVA molecules on the composite surface could play an important role for the improvement of the anti‐fouling property and the enhancement of flux recovery rate of the composite membrane. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Totally bioresorbable composites prepared from poly(l‐lactide)‐co‐(trimethylene carbonate) copolymers and poly(l‐lactide)‐co‐(glycolide) fibers as cardiovascular stent material
Authors: Han Yaru , Jin Xiaoyun , Yang Jian , Fan Zhongyong , Lu Zhiqian , Zhang Yong , Li Suming 
Published: December 2011

AbstractThis paper aims to evaluate the potential of totally bioresorbable composites as cardiovascular stent material. Copolymers were synthesized by ring‐opening polymerization of L‐lactide (LLA) and 1,3‐trimethylene carbonate (TMC) with LLA‐TMC ratios of 3/1, 4/1, and 5/1 and characterized by nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), and differential scanning calorimetry (DSC). Wt. 5% of poly(L‐lactide)‐co‐(glycolide) (PLGA) fibers are used to reinforce PTMC‐LLA copolymer matrices to prepare totally bioresorbable composites. Heat treatment under vacuum and oxygen plasma treatment are applied to improve the mechanical performance of the composites in terms of eliminating the imperfections inside, enhancing interfacial affinity, surface roughness, and enriching surface oxidative chemical bonds. After plasma treatment, the viscosity and tensile strength of the fibers decrease, but the surface chemical bonds are enriched and surface roughness is increased. The composites with 15‐min plasma‐treated fibers and 2 h heat treatment exhibit the highest tensile strength of 46 MPa, i.e., very close to that of PLLA (48 MPa), which is usually used as biodegradable stent material. Moreover, the tensile modulus of the above composite is 1711 MPa, which is only 34% of PLLA's modulus (4985 MPa). Therefore, novel composites with sufficient tensile strength and better flexibility are obtained as promising cardiovascular stent material. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers
Crystallization behavior of poly(ϵ‐caprolactone)/Tio2 nanocomposites obtained by in situ polymerization
Authors: Wei Zhiyong , Wang Guangshuo , Wang Pei , Liu Lian , Qi Min 
Published: December 2011

AbstractPoly(ϵ‐caprolactone) (PCL)/titanium dioxide (TiO2) nanocomposites were prepared by in situ polymerization of ϵ‐caprolactone in the presence of modified‐TiO2 nanoparticles as initiators. The molecular weight of PCL matrix was dependent on the amount of the TiO2 fillers. The incorporation of TiO2 did not significantly affect the crystalline structure of PCL. Moreover, a tendency of the nanoparticles to form aggregates was observed, especially at higher fillers contents. The analysis of the crystallization process showed that the addition of TiO2 nanoparticles accelerated the crystallization rate of PCL, and the crystallization rates increased by increasing the filler content. The crystallization activation energy dependence on the filler content observed here is probably the consequence of the two competing factors. The tendency of activation energy obtained by nonisothermal crystallization is similar to that of isothermal crystallization. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
The effect of a polypropylene skin on the structure and properties of PE/PP dual layer pressure pipe
Authors: Huang Jian , Gilbert Marianne , Bowman Jeremy 
Published: December 2011

AbstractA new and growing family of polyethylene (PE)‐based pressure pipes have a polypropylene (PP) skin. The effect of the PP skin on the structure and properties of the core PE pipe was investigated by comparing the skinned pipe with an uncoated pipe made from the same PE material and with the same dimensions. The annealing effect introduced by the skin changed the PE core pipe density profile across the wall thickness, increasing density in the PE core pipe near to its outer surface. The density at the bore of the coated and the uncoated pipe was similar. The melting temperature and enthalpy of melting data from DSC agreed with the density profile results. The melting temperature of PE core pipe material close to the PP skin increased with increasing skin thickness. Residual stress assessment indicated that, as the PP skin thickness increased, the PE core pipe had a lower level of overall residual stress in the hoop direction. Long‐term hydrostatic strength (LTHS) tests were carried out and showed a higher strength for the coated pipe than the uncoated one. The observed structural changes have been used to explain the relative strength of these two PE pipes. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Rheological, physical, and thermal characterization of single‐site catalyst based polyethylenes for seal layer applications
Authors: Sadeghi F. , Ajji A. 
Published: December 2011

AbstractFour single‐site metallocene catalyst based polyethylenes (mPEs), one ultra low density polyethylene, one conventional linear low density polyethylene (LLDPE), and one low density polyethylene (LDPE) were selected to characterize the effect of side chain branches on physical and mechanical properties. Rheological experiments were carried out to extract complex viscosity and elasticity as a function of frequency. Elongational viscosity tests were also performed to assess long chain branching. For some mPEs, sparse long chain branching improved shear thinning and elasticity of the chains in melt state. During elongation, mPEs with a narrow linear chain distribution showed initially greater melt strength whereas for longer elongation, the mPEs with long chain branching lead over in strength. Cast films were produced from the mPEs and their physical (such as crystallinity, crystal size) and mechanical properties were tested. A double melting peak was observed in the differential scanning calorimetry thermograms of the mPE films. A relatively sharp strain hardening behavior in tensile tests was observed for the mPEs films when compared to LLDPE. Fourier transform infrared was used as an effective and fast method to investigate side chain length. It was found that the positioning of side chain, co‐monomer length, and content influence the melting behavior of mPE films. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Influence of cure conditions on properties of resol/layered silicate nanocomposites
Authors: López Marta , Blanco Miren , Martin Maria , Mondragon Iñaki 
Published: December 2011

AbstractThe effects on clay exfoliation of organic modification of montmorillonite (MMT) and the nature of the catalyst used during the synthesis and curing of a MMT modified phenolic resol resin were investigated. The impact on the final properties of other parameters such as reactivity ratio and temperature of condensation were also analyzed in order to optimize the conditions to prepare a customized organoclay‐based nanocomposite. Nanocomposites were analyzed by means of wide angle X‐ray scattering (WAXS), optical microscopy (TOM), and atomic force microscopy (AFM) techniques. The formation of either intercalated or quasi‐exfoliated structure was assessed in some systems. Thermal and mechanical properties of the cured composites were evaluated and correlated to their morphologies. More homogenous clay dispersion was achieved for composites prepared with aminoacid‐modified MMT, triethylamine (TEA) as catalyst, formaldehyde/phenol molar ratio (F/P) 2.0, and curing at 80°C. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
The effects of nanoclay dispersion levels and processing parameters on the dynamic vulcanization of TPV nanocomposites based on PP/EPDM prepared by reactive extrusion
Authors: Mirzadeh Amin , Lafleur Pierre G. , Kamal Musa R. , Dubois Charles 
Published: December 2011

AbstractThe study considers the effects of different dispersion levels of nanoclay on the crosslinking reaction of thermoplastic vulcanizate (TPV) nanocomposites based on polypropylene/ethylene propylene diene M‐class rubber (PP/EPDM). PP nanocomposites with dispersion level ranging from intercalated structures to a mixture of intercalated tactoids and exfoliated layers were used as the thermoplastic phase. Dimethylol phenolic resin or octylphenol‐formaldehyde resin was used as curing agents, along with stannous chloride dihydrate as the catalyst, to vulcanize the rubber phase during the reactive extrusion process. Initially, temperature effects were investigated in internal batch mixer. Subsequently, the effects of screw speed (i.e., shear rate and residence time) were evaluated along the screw length. Different criteria such as nuclear magnetic resonance (NMR) signal line width, bound curative content, and residual diene concentration were used to evaluate the extent of crosslinking, along with normalized storage modulus and gel content. X‐ray diffraction (XRD) analysis and transmission electron microscopy (TEM) micrographs showed that the dynamic vulcanization process improves the dispersion level of nanoclay in the final TPVs. It was found that the presence of nanoclay influences the crosslinking reaction, mainly through its effect on the continuity index of the EPDM phase. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Effect of cavity surface coating and molding parameters on pressure drop: Developing a new software for rapid calculations
Authors: Martinez Arantza , Aznar Javier , Acero Camilo 
Published: December 2011

AbstractNowadays, many of the plastic components are aesthetic pieces, and they are fabric, thermoplastic vulcanizates (TPVs), or film coated. In the case of upholstered pieces, they are injected onto a textile tissue introduced into the mold, and they are finished with an edging process. Simulation programs used to optimize the injection process are not able to simulate the injection over fabrics, and therefore, it is difficult to select an injection machine without knowing the pressure drop inside the mold and without knowing how the parameters affect to the injection cycle or to the aesthetic aspect of this kind of pieces. This article presents a software for rapid calculations during the filling phase without the need for complex modeling. The program will be able to calculate pressure drop and other flow parameters that are fundamental for a good design of an industrial mold used in in‐mold decoration (IMD) technique. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Model for a two‐cavity coating die with pressure and temperature deformation
Authors: Shetty Sneha , Ruschak Kenneth J. , Weinstein Steven J. 
Published: December 2011

AbstractCoating dies uniformly distribute liquid for application as a film to moving substrates using one or two cavities spanning the coating width and adjoining precision narrow slots of much higher resistance to flow. If the slots are deformed by the pressure of the liquid or by temperature gradients in the die bars, degradation in flow distribution can result. Consequently, dies are designed to be sufficiently stiff and are thermally jacketed to keep slot deformations within fabrication tolerances. To aid in design and operation, a model of low computational load is developed in which the flow and deformation analyses are directly coupled. Die deformation is modeled using classical beam theory taking account of the varying thickness of the bars due to cavity geometry. Two‐dimensional finite element analysis of die deformation gives marginally higher slot deformation. Three‐dimensional finite element analysis agrees with the two‐dimensional analysis except near the center of the die where the symmetry boundary condition reduces deformation. The effects of die geometry on deformation and flow distribution are illustrated. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Structure–property relationship studies in amine functionalized multiwall carbon nanotubes filled polypropylene composite fiber
Authors: Tambe Pankaj B. , Bhattacharyya Arup R. , Kamath Srikanth S. , Kulkarni Ajit R. , Sreekumar T.V. , Srivastav Anurag , Rao K.U. Bhasker , Liu Yaodong , Kumar Satish 
Published: December 2011

AbstractAmine functionalized multiwalled carbon nanotubes (a‐MWNT) based polypropylene (PP) composite fibers were prepared in the presence of polypropylene‐g‐maleic anhydride (PP‐g‐MA) by melt‐mixing followed by melt‐spinning with subsequent post‐drawing of the as‐spun fibers of varying draw ratio (DR). In order to enhance the interfacial interaction, a‐MWNT were utilized in combination with PP‐g‐MA during melt‐mixing. Fourier transform infrared spectroscopic analysis revealed the formation of imide bonds between MA functionality of PP‐g‐MA and amine functional group of a‐MWNT. Higher tensile properties of PP/a‐MWNT/PP‐g‐MA composite fibers were registered with varying DR of the as‐spun fiber. Orientation factors of a‐MWNT and PP chains along the fiber axis were correlated with the higher tensile modulus and tensile strength of PP/a‐MWNT/PP‐g‐MA composite fiber of varying DR. Crystallization studies indicated the role of hetero‐nucleating action of a‐MWNT in PP/a‐MWNT/PP‐g‐MA composite fiber. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers
Investigation of Cu(In,Ga)Se2 thin‐film formation during the multi‐stage co‐evaporation process
Authors: Caballero R. , Kaufmann C. A. , Efimova V. , Rissom T. , Hoffmann V. , Schock H. W. 
Published: December 2011

ABSTRACTIn order to transfer the potential for the high efficiencies seen for Cu(In,Ga)Se2 (CIGSe) thin films from co‐evaporation processes to cheaper large‐scale deposition techniques, a more intricate understanding of the CIGSe growth process for high‐quality material is required. Hence, the growth mechanism for chalcopyrite‐type thin films when varying the Cu content during a multi‐stage deposition process is studied. Break‐off experiments help to understand the intermediate growth stages of the thin‐film formation. The film structure and morphology are studied by X‐ray diffraction and scanning electron microscopy. The different phases at the film surface are identified by Raman spectroscopy. Depth‐resolved compositional analysis is carried out via glow discharge optical emission spectrometry. The experimental results imply an affinity of Na for material phases with a Cu‐poor composition, affirming a possible interaction of sodium with Cu vacancies mainly via In(Ga)Cu antisite defects. An efficiency of 12.7% for vacancy compound‐based devices is obtained. Copyright © 2011 John Wiley & Sons, Ltd.
Annual performance enhancement of building integrated photovoltaic modules by applying phase change materials
Authors: Hendricks J. H. C. , van Sark W. G. J. H. M. 
Published: December 2011

AbstractThe performance of photovoltaic (PV) module outdoors suffers from attained high module temperatures due to irradiation as a result of the negative temperature coefficient of their efficiency. Phase change materials (PCMs) are investigated as an option to regulate photovoltaic module temperature and thereby reduce its electrical efficiency decrease. In this study, a simplified heat balance model is used to calculate the extra energy gain; such a PV/PCM system can bring on an annual basis. With present day commercially available PCM materials, a moderate increase of up to 3% of the total energy output can be expected. When taking into account the additional PCM material cost, a PV/PCM module presently is not economically viable. For an acceptable payback period of 10–20 years to be reached, the heat storage capacity of a PCM would require an increase of about one order of magnitude, which is presently not realistic. Nevertheless, a combination with building climate control in which the PCM plays a double role controlling both the PV temperature as well as the inside climate temperature may be feasible. Copyright © 2011 John Wiley & Sons, Ltd.
Thoracic Hyperkyphosis: A Survey of Australian Physiotherapists
Authors: Perriman Diana M. , Scarvell Jennifer M. , Hughes Andrew R. , Lueck Christian J. , Dear Keith B. G. , Smith Paul N. 
Published: December 2011

AbstractBackgroundAge‐related thoracic hyperkyphosis can lead to poor health outcomes including pain and dysfunction. Physiotherapists are fundamentally involved in the assessment and treatment of this problem but there is no published data that details assessment and treatment strategies or the attitudes of practitioners with respect to hyperkyphosis.PurposeThe purpose of the study is to ascertain current physiotherapy practice for, and attitudes to, the assessment and treatment of thoracic hyperkyphosis in Australia.MethodA stratified random sample (N = 468) of Australian physiotherapists in all states and territories working in hospitals, outpatient clinics and community clinics were sent an anonymous cross‐sectional postal survey. The survey had six sections identifying clinical profile, prevalence, measurement strategy, treatment frequency, treatment strategy and evidence source.ResultsA response rate of 47% with anonymity preserved was achieved. The majority of respondents had a musculoskeletal practice profile (75%). Seventy‐eight per cent encountered hyperkyphosis at least weekly, and three treatment sessions were most commonly given (35%). Visual inspection was almost universally used to assess the degree of hyperkyphosis (98%), and for 64% it was their only measurement tool. Postural re‐education was the most common treatment strategy (90%) but the range of treatments reported was diverse. The primary source of evidence used by the majority of respondents was their undergraduate education, and there was concern expressed that physiotherapists lack good evidence upon which to make therapeutic decisions about hyperkyphosis.ConclusionsThoracic hyperkyphosis is commonly encountered by physiotherapists. Measurement of treatment efficacy is highly subjective, and the treatment modalities employed are diverse. Many physiotherapists based their management of hyperkyphosis on their undergraduate education alone. Copyright © 2011 John Wiley & Sons, Ltd.