bluuebunny/crossref_metadata_2025 huggingface dataset:
Does sex sell? The effect of sexual programme content on the recall of sexual and non‐sexual advertisements
Authors: Parker Ellie , Furnham Adrian
Published: January 2007

This study looked at the recall of sexual and non‐sexual television advertisements embedded within programmes, with or without, sexual content. It was predicted that there would be a detrimental effect of sexual programme content, and a beneficial effect of sexual advertisement content on ability to recall advertisements. Further, when programme and advertisement content were congruous (i.e. both sexual), this also would hinder recall. Participants aged between 18 and 31 were placed in one of four conditions and were shown either ‘Sex and the City’ (sexual programme) or ‘Malcolm in the Middle’ (non‐sexual programme) with sexual or non‐sexual advertisements embedded in each. Participants were then asked to recall advertisement details from the advertisements. The results indicated that there was a main effect of programme type, demonstrating that sexual programme content hindered recall of advertisements. However, there was no main effect of the type of advertisements seen (sexual or non‐sexual) on recall, nor was there a negative effect on recall when programme and advertisement content were congruous. An interaction between advertisements and sex of participants showed that males recalled sexual advertisements better and females recalled non‐sexual advertisements better. Limitations of the study are considered. Copyright © 2007 John Wiley & Sons, Ltd.
Chronic and temporary aggression causes hostile false memories for ambiguous information
Authors: Takarangi Melanie K. T. , Polaschek Devon L. L. , Hignett Andrew , Garry Maryanne
Published: January 2007

Chronic and temporarily aggressive people show a phenomenon known as the hostile attribution bias (HAB), in which access to hostile schemas leads them to interpret ambiguously hostile information in a hostile way. Can these people also be induced to remember unambiguously hostile, yet completely false information? To address this question, we investigated the effect of both chronic and temporary aggression on recall for a list containing words that could be interpreted as exemplars of either an aggressive (violence‐related) or non‐aggressive (kitchen‐related) category. Subjects were exposed to five consecutive lists of associated words including the ambiguous list, but half read a list of insult words immediately before presentation of the ambiguous list, while the other half read only emotionally neutral lists. When recalling the ambiguous list, aggressive subjects and subjects who were primed with insult words were more likely to report having seen unpresented aggressive words compared with their low aggressive and not primed counterparts. We discuss our findings in line with Anderson and Bushman's (2002) General Aggression Model (GAM). Copyright © 2007 John Wiley & Sons, Ltd.
Photoconductivity of a Low‐Bandgap Conjugated Polymer
Authors: Soci C. , Hwang I.‐W. , Moses D. , Zhu Z. , Waller D. , Gaudiana R. , Brabec C. J. , Heeger A. J.
Published: January 2007

The photoconductive properties of a novel low‐bandgap conjugated polymer, poly[2,6‐(4,4‐bis‐(2‐ethylhexyl)‐4H‐cyclopenta[2,1‐b;3,4‐b′]dithiophene)‐alt‐4,7‐(2,1,3‐benzothiadiazole)], PCPDTBT, with an optical energy gap of Eg ∼ 1.5 eV, have been studied. The results of photoluminescence and photoconductivity measurements indicate efficient electron transfer from PCPDTBT to PCBM ([6,6]‐phenyl‐C61 butyric acid methyl ester, a fullerene derivative), where PCPDTBT acts as the electron donor and PCBM as the electron acceptor. Electron‐transfer facilitates charge separation and results in prolonged carrier lifetime, as observed by fast (t > 100 ps) transient photoconductivity measurements. The photoresponsivities of PCPDTBT and PCPDTBT:PCBM are comparable to those of poly(3‐hexylthiophene), P3HT, and P3HT:PCBM, respectively. Moreover, the spectral sensitivity of PCPDTBT:PCBM extends significantly deeper into the infrared, to 900 nm, than that of P3HT. The potential of PCPDTBT as a material for high‐efficiency polymer solar cells is discussed.
From Mesostructured Wurtzite ZnS‐Nanowire/Amine Nanocomposites to ZnS Nanowires Exhibiting Quantum Size Effects: A Mild‐Solution Chemistry Approach
Authors: Yao W.‐T. , Yu S.‐H. , Wu Q.‐S.
Published: January 2007

Mesostructured wurtzite ZnS‐nanowire‐bundle/amine nanocomposites displaying remarkable quantum size effects are synthesized by using a mild‐solution reaction using different amines, such as n‐butylamine, ethylamine, and tetraethylenepentamine, Zn(NO3)2·6 H2O, and CS(NH2)2 or Na2S·9 H2O as the precursors at temperatures ranging from room temperature to 180 °C. A possible mechanism for the shape‐controlled growth of ZnS nanowires and nanocomposites is proposed. Increasing the reaction temperature or dispersing the composite in acetic acid or NaOH solution leads to the destruction of the periodic structure and the formation of individual wurtzite nanowires and their aggregates. The nanowire/amine composites and individual wurtzite nanowires both display obvious quantum size effects. Strong band‐edge emission is observed for the wurtzite ZnS nanowires after removal of the amine. The optical properties of these nanocomposites and nanowires are strongly related to the preparation conditions and can be finely tuned. This technique provides a unique approach for fabricating highly oriented wurtzite ZnS semiconductor nanowires, and can potentially be extended to other semiconducting systems.
Ultrafast Spectroscopic Study of Photoinduced Electron Transfer in an Oligo(thienylenevinylene):Fullerene Composite
Authors: Hwang I.‐W. , Xu Q.‐H. , Soci C. , Chen B. , Jen A. K.‐Y. , Moses D. , Heeger A. J.
Published: January 2007

Photoinduced electron transfer and competing processes have been studied in composites of an oligo(thienylenevinylene) (OTV), comprised of ten dibuthoxyl‐thiophene units separated by vinylene units, and a C60 derivative, [6,6]‐phenyl‐C61 butyric acid methyl ester (PCBM), by using femtosecond transient absorption spectroscopy and sub‐nanosecond transient photoconductivity. We find that in OTV:PCBM the photoexcitations decay primarily via intrachain relaxation rather than photoinduced electron transfer from OTV to PCBM. The electron‐transfer process requires ca. 14 ps; larger by more than two orders of magnitude than the required time observed in conjugated‐polymer:C60 composites, and also larger than the 0.6 ps singlet‐state lifetime in OTV. These observations indicate that the quantum efficiency for photoinduced electron transfer in OTV:PCBM is less than 5 %.
Siliceous Unilamellar Vesicles and Foams by Using Block‐Copolymer Cooperative Vesicle Templating
Authors: Wang H. , Wang Y. , Zhou X. , Zhou L. , Tang J. , Lei J. , Yu C.
Published: January 2007

By employing commercial poly(ethylene oxide)–poly(propylene oxide)–poly(ethylene oxide) (PEO–PPO–PEO) block copolymers as templates in near‐neutral aqueous solutions in the absence of organic cosolvents, unilamellar siliceous vesicles and nanofoams with ultrahigh pore volumes (> 3 cm3 g–1) are successfully synthesized. At controlled pH, a tubular micelle → unilamellar vesicle → nanofoam structural transformation is observed by increasing the reaction temperature. It is proposed that the siliceous vesicles are synthesized via a co‐operative block‐copolymer vesicle templating approach, while the siliceous nanofoams are obtained by the fusion of vesicles at increased ionic strength. Compared to literature methods to synthesize siliceous vesicles and foams, our method is convenient, cheap, and produces a high yield. Siliceous nanofoams synthesized by using our approach show superior bioimmobilization capacity over other porous materials for biomolecules with large molecular weight.
Protein‐Mediated Synthesis of Uniform Superparamagnetic Magnetite Nanocrystals
Authors: Prozorov T. , Mallapragada S. K. , Narasimhan B. , Wang L. , Palo P. , Nilsen‐Hamilton M. , Williams T. J. , Bazylinski D. A. , Prozorov R. , Canfield P. C.
Published: January 2007

Magnetite nanocrystals are synthesized in the presence of a recombinant Mms6 protein thought to be involved in the biomineralization of bacterial magnetite magnetosomes, the mammalian iron‐storage protein, ferritin, and two proteins not known to bind iron, lipocalin (Lcn2) and bovine serum albumin (BSA). To mimic the conditions at which magnetite nanocrystals are formed in magnetotactic bacteria, magnetite synthesis is performed in a polymeric gel to slow down the diffusion rates of the reagents. Recombinant Mms6 facilitates formation of ca. 30 nm single‐domain, uniform magnetite nanocrystals in solution, as verified by using transmission electron microscopy analysis and magnetization measurements. The nanocrystals formed in the presence of ferritin, Lcn2, and BSA, do not exhibit the uniform sizes and shapes observed for those produced in the presence of Mms6. Mms6‐derived magnetite nanoparticles show the largest magnetization values above the blocking temperature, as well as the largest magnetic susceptibility compared to those of the nanomaterials synthesized with other proteins. The latter is indicative of a substantial effective magnetic moment per particle, which is consistent with the presence of magnetite with a well‐defined crystalline structure. The combination of electron microscopy analysis and magnetic measurements confirms our hypothesis that Mms6 promotes the shape‐selective formation of uniform superparamagnetic nanocrystals. This provides a unique bioinspired route for synthesis of uniform magnetite nanocrystals.
Fabrication of Superhydrophobic Surfaces on Engineering Materials by a Solution‐Immersion Process
Authors: Qu M. , Zhang B. , Song S. , Chen L. , Zhang J. , Cao X.
Published: January 2007

Superhydrophobic surfaces on engineering materials are prepared via a convenient solution‐immersion method. The binary geometric structures at the micro‐ and nanometer scale bestow superhydrophobic properties on the surfaces. The surfaces show stable superhydrophobicity even in many corrosive solutions, such as acidic or basic solutions over a wide pH range, and also in salt solutions. The procedure is time‐saving, inexpensive, and fairly facile to carry out. It is expected that this facile technique will accelerate the large‐scale production of superhydrophobic engineering materials with new industrial applications.
Colloidal Suspensions of Nanometer‐Sized Mesoporous Silica
Authors: Möller K. , Kobler J. , Bein T.
Published: January 2007

Nanometer‐sized surfactant‐templated materials are prepared in the form of stable suspensions of colloidal mesoporous silica (CMS) consisting of discrete, nonaggregated particles with dimensions smaller than 200 nm. A high‐yield synthesis procedure is reported based on a cationic surfactant and low water content that additionally enables the adjustment of the size range of the individual particles between 50 and 100 nm. Particularly, the use of the base triethanolamine (TEA) and the specific reaction conditions result in long‐lived suspensions. Dynamic light scattering reveals narrow particle size distributions in these suspensions. Smooth spherical particles with pores growing from the center to the periphery are observed by using transmission electron microscopy, suggesting a seed‐growth mechanism. The template molecules could be extracted from the nanoscale mesoporous particles via sonication in acidic media. The resulting nanoparticles give rise to type IV adsorption isotherms revealing typical mesopores and additional textural porosity. High surface areas of over 1000 m2 g–1 and large pore volumes of up to 1 mL g–1 are obtained for these extracted samples.
Sulfonation of poly(phthalazinone ether sulfone ketone) by heterogeneous method and its potential application on proton exchange membrane (PEM)
Authors: Wu Xuemei , He Gaohong , Gu Shuang , Chen Wan , Yao Pingjing
Published: January 2007

A series of sulfonated PPESK (SPPESKs) were synthesized through a heterogeneous sulfonation process with fuming sulfuric acid as sulfonating agent in a chloroform solvent. Membranes prepared from SPPESKs were investigated and proved to be candidates of proton exchange membrane in fuel cell operating at high temperature and low humidity. The heterogeneous sulfonation reaction is verified to first occur on the interface of the acid phase and the chloroform phase, then went on in the acid phase. SPPESKs with sulfonation degree (DS) up to 2.0 are obtained through a new reprecipitation method. Effects of reaction temperature, reaction time, acid/polymer ratio, and chloroform/polymer ratio on the sulfonation reaction are reported in details. An increase in sulfonation degree results in the increase of hydrophilicity, bringing about a substantial gain in proton conductivity. SPPESK membranes exhibit high water uptake of about 105.4% with DS of 1.01, almost two times higher than that of Nafion® with similar dimensional variation. Conductivity values at 35°C, 60% R.H. ranging from 10−3 to 10−2 S/cm were measured, which are comparable to or higher than that of Nafion® 112 (1.635 × 10−2 S/cm) under the same test condition. Thermogravimetric analysis shows that SPPESK membranes are stable up to 290°C in N2. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1002–1009, 2007
Morphology of poly(styrene‐block‐dimethylsiloxane) copolymer films
Authors: Wu Ningjing , Zheng Anna , Huang Yongmin , Liu Honglai
Published: January 2007

The morphologies of poly(styrene‐block‐di‐methylsiloxane) (PS‐b‐PDMS) copolymer thin films were analyzed via atomic force microscopy and transition electron microscopy (TEM). The asymmetric copolymer thin films spin‐cast from toluene onto mica presented meshlike structures, which were different from the spherical structures from TEM measurements. The annealing temperature affected the surface morphology of the PS‐b‐PDMS copolymer thin films; the polydimethylsiloxane (PDMS) phases at the surface were increased when the annealing temperature was higher than the PDMS glass‐transition temperature. The morphologies of the PS‐b‐PDMS copolymer thin films were different from solvent to solvent; for thin films spin‐cast from toluene, the polystyrene (PS) phase appeared as pits in the PDMS matrix, whereas the thin films spin‐cast from cyclohexane solutions exhibited an islandlike structure and small, separated PS phases as protrusions over the macroscopically flat surface. The microphase structure of the PS‐b‐PDMS copolymer thin films was also strongly influenced by the different substrates; for an asymmetric block copolymer thin film, the PDMS and PS phases on a silicon substrate presented a lamellar structure parallel to the surface at intervals. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1010–1018, 2007
Effect of glycolide monomer on release behavior of gentamicin sulfate‐loaded PLGA microparticles
Authors: Yoo Je Young , Shin Joon Hyun , Khang Gilson , Shin Hyung Sik , Yuk Soon Hong , Kim Yong Sik , Kim Moon Suk , Rhee John M. , Lee Hai Bang
Published: January 2007

For the treatment of osteomyelitis and the prevention of infections after orthopedic surgery, topically implantable gentamicin sulfate (GS)‐loaded poly(D,L‐lactide‐co‐glycolide) microparticles (GSMP) containing glycolide monomer (GM), as a biodegradable and nontoxic material, were prepared by melt‐extrusion method without organic solvent for controlled release. After preparation of polymer blend, the powders of different size (90–1200 μm) were obtained by means of freezer‐mill. The influences of GM and particle size were investigated on the GS release patterns. GSMP containing GM (in case of 10% loaded) showed a near‐zero order release from 2 to 7 days with the initial burst. GM affected to increase of GS release rate during the in vitro release test. The pH variations of the media were investigated to determine effect of GM on pH drop of media. The morphological evaluations, change of molecular weight, and thermal property of microparticles were characterized by scanning electron microscope, gel permeation chromatography, and differential scanning calorimeter, respectively. Bacterial inhibition zone test was established to identify antibiosis of GS. It showed antibiotic areas except control sample. From these results, the authors expected that GSMP containing GM would be a good dosage form as a topically implantable device that can get rid of lag period of GSMP. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1019–1025, 2007
Electrospinning of keratin/poly(ethylene oxide)blend nanofibers
Authors: Aluigi A. , Varesano A. , Montarsolo A. , Vineis C. , Ferrero F. , Mazzuchetti G. , Tonin C.
Published: January 2007

Research on the electrospinning of nanofibers has increased in recent years because of the number of potential applications in different areas, ranging from technical textiles (e.g., filters, composite reinforcements, and protective fabrics) to biomedical commodities and devices such as bandages, membranes, bioactive surfaces, and porous substrates for tissue engineering, for which biocompatible polymers play an essential role. In this work, wool keratin/poly(ethylene oxide) nanofibers were electrospun from aqueous solutions of polymer blends under different operating conditions. The filaments were characterized with scanning electron microscopy, Fourier transform infrared, and differential scanning calorimetry analyses and compared with films of the same materials produced via casting with the aim of investigating structural changes due to the electrospinning process. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 863–870, 2007
Synthesis and properties of copolymer microemulsions of siloxane and acrylate with a high solid content
Authors: Zhang Li , Zhang Chen , Li Guoming
Published: January 2007

Copolymer microemulsions of methyl methacrylate, butyl acrylate, and vinyltriisopropoxysilane with high monomer/surfactant ratios were prepared through a seeded semicontinuous polymerization in the presence of a redox initiator, ammonium persulfate/sodium hydrosulfate. The mean diameter of the particles decreased with an increase in the amount of the surfactant, the monomer concentration, and the vinyltriisopropoxysilane/monomer ratio, but it increased with an increase in the concentration of the initiator. When the initiator concentration was 0.23% (ammonium persulfate/sodium hydrosulfate = 1.5 : 1), the concentration of the composite surfactant was 0.9 wt %, and the reaction temperature was 50°C; the solid content of the microemulsion could be up to 43% with a small particle size (mean diameter) of 39.8 nm. The chemical, freeze–thaw, and mechanical stability of the latexes was tested as well as the thermal stability of the films. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 851–857, 2007
Impact of approximating the initial bubble pressure on cell nucleation in polymeric foaming processes
Authors: Leung Siu N. , Li Hongbo , Park Chul B.
Published: January 2007

According to the classical nucleation theory, the free energy barrier for bubble nucleation, and thereby the nucleation rate, are functions of the initial bubble pressure, Pbubble,0. In almost all of the previous studies that have used computer simulations to investigate polymeric foaming processes, the value of Pbubble,0 has been approximated using the saturation pressure, Psat. This article employs the thermodynamic equilibrium condition and the Sanchez–Lacombe (SL) equation of state (EOS) to determine the value of Pbubble,0. It is shown that using Psat to approximate Pbubble,0 may lead to significant overestimations of the nucleation rate and the final cell density. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 902–908, 2007
Preparation and properties of polyimides based on bis[3,5‐dimethyl‐4‐(4‐aminophenoxy)phenyl]methane
Authors: Yuan Yuan , Lin Bao‐Ping , Sun Yue‐Ming
Published: January 2007

A series of polyimide (PI) thin films were synthesized based on bis[3,5‐dimethyl‐4‐(4‐aminophenoxy)phenyl]methane and conventional aromatic dianhydrides. The structures and properties of the thin films were measured with Fourier transform infrared, NMR, thermogravimetric analysis, dynamic mechanical analysis, and impedance analysis. The PI films exhibited glass‐transition temperatures in the range of 211–300°C and possessed initial thermal decomposition temperature reaching up to 457–482°C in air and 461–473°C in nitrogen. Some PI films had high solubility in organic solvents such as 1‐methyl‐2‐pyrrolidinone, N,N‐dimethylformamide, N,N‐dimethylacetamide, dimethyl sulfoxide, m‐cresol, tetrahydrofuran, and CHCl3. The mechanical properties of these films were also examined. The dielectric constants of the films were in the range of 2.8–3.3 at 25°C. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1265–1270, 2007
The effect of fabrication methods on the mechanical and thermal properties of poly(lactide‐co‐glycolide) scaffolds
Authors: Forcino Rachel G. , Jonnalagadda Sriramakamal
Published: January 2007

The purpose of this research was to evaluate the effects of the fabrication method, poly(ethylene glycol) (PEG) molecular weight, and PEG concentration on the mechanical and thermal properties of blended poly (lactide‐co‐glycolide) (PLGA)/PEG scaffolds. The manufacturing process was the dominant factor. The tested fabrication processes were compression, heat molding, and solvent casting/vacuum drying. The scaffolds produced by compression were strong and brittle with mechanical properties [compressive modulus (E) ∼ 400 N/mm2] comparable to those of trabecular bone. The heat‐molded scaffolds were weaker and more ductile (E ∼ 45 N/mm2) than the compressed scaffolds, so they were more applicable to non‐load‐bearing applications. The vacuum‐dried scaffolds completely lacked compressive strength (E ∼ 5 N/mm2) and were considered unsuitable for scaffolding applications. The miscibilities of the blends were also affected by the processing method and were evaluated on the basis of the melting‐point depression of crystalline PEG. The miscibility of PLGA in PEG was greatest with vacuum drying (6–13%), followed by heat molding (0.4–1.5%) and then compression (0.2–0.8%). The application of heat and solvent to the blend successfully altered the miscibility of the two polymers. Overall, this study demonstrates the ability to fabricate scaffolds with distinct thermal and mechanical characteristics by the manipulation of the fabrication method. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 944–949, 2007
Composition of the cell wall in the stem and leaf sheath of wheat straw
Authors: Yu Hui , Liu Ruigang , Qiu Limei , Huang Yong
Published: January 2007

The composition of the cell wall of the stem and leaf sheath of extracted wheat straw was studied with X‐ray photoelectron spectroscopy and with a field emission scanning electron microscope equipped with an energy‐dispersive microanalysis system. The outer side (epidermal side) had more lignin, and the inner side (lumen side) of the stem was rich in cellulose. The compositions of the two sides of the leaf sheath were a little different. The chemical components for the same tissue at different growth stages were essentially constant, and this indicated that cellulose, lignin, and hemicelluloses deposited in constant proportions in the cell wall of the same tissue during growth. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1236–1240, 2007
Shear and elongational rheology of polyethylenes with different molecular characteristics. II. Elongational rheology
Authors: Wei X. , Collier J. R. , Petrovan S.
Published: January 2007

The elongational viscosities of polyethylenes with different molecular characteristics were measured at different Hencky strains and temperatures with a capillary rheometer by the replacement of the capillary cylindrical die with a hyperbolic converging die. The hyperbolic shape of the die established a purely elongational flow field at a constant elongational strain rate throughout the die. The effects of molecular characteristics such as the molecular weight, molecular weight distribution, and long‐chain branching and processing conditions such as the temperature and Hencky strain on the elongational rheology of the polyethylene samples were studied. Good master curves were generated for temperature and Hencky strain shifting and simultaneous shifting with respect to both the temperature and Hencky strain. Both the molecular weight distribution and long‐chain branching seemed to promote strain rate thinning and reduce the elongational viscosity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1184–1194, 2007
Substitution of di(2‐ethylhexyl) phthalate by di(isononyl) cyclohexane‐1,2‐dicarboxylate as a plasticizer for industrial vinyl plastisol formulations
Authors: Crespo J. E. , Balart R. , Sanchez L. , López J.
Published: January 2007

The use of plasticizers with low environmental impact is one of the most interesting research fields in the plasticizer additives industry because of the possible toxicity of o‐phthalates. Among the wide variety of new plasticizers, it is important to note the use of di(isononyl) cyclohexane‐1,2‐dicarboxylate (DINCH), which shows a structure similar to the most commonly used o‐phthalates, that is, diisononyl phthalate and di(2‐ethylhexyl) phthalate (DEHP). It is necessary to evaluate the processing conditions (temperature and curing time) regarding the mechanical properties to study the possibilities for substituting conventional plasticizers and to determine whether changes in the processing conditions are needed for use in industrial applications. In this work, we carried out a comparative study of the optimum curing conditions and mechanical performance of DEHP and DINCH as plasticizers. The obtained results show that the viscosities of DINCH and DEHP‐based plastisols were similar. Furthermore, the mechanical properties of the flexible poly(vinyl chloride) obtained from DINCH‐based plastisols were very interesting for industrial applications. All of this favored the substitution of DEHP by DINCH as plasticizer for flexible poly‐ (vinyl chloride). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1215–1220, 2007
Amine‐derivatized poly(diallyldimethylammonium chloride) from N‐vinylformamide copolymerization
Authors: Tanaka Masayoshi , Tanaka Hiroo , Pelton Robert
Published: January 2007

The reactivity ratios for the aqueous free‐radical copolymerization of diallyldimethylammonium chloride and N‐vinylformamide were found to be 0.13 and 1.92, respectively, from a Fineman–Ross analysis of a series of batch polymerizations. Because batch polymerization could not give a uniform product in a high yield with two monomers of such different reactivities, a semibatch procedure was developed in which the more reactive N‐vinylformamide was added in 10 steps over the course of the copolymerization. The poly(diallyldimethyl‐ ammonium chloride‐co‐N‐vinylformamide) copolymers were hydrolyzed to give poly(diallyldimethylammonium chloride‐co‐vinylamine). The utility of the vinylamine/diallyldimethylammonium chloride copolymers was demonstrated by the preparation and characterization of three derivatives: (1) a copolymer with coupled dansyl groups for fluorescence detection; (2) a copolymer with coupled dabsyl groups for ultraviolet–visible detection; and (3) an ultra‐high‐molecular‐weight (1.6 × 106 Da) poly(diallyldimethylammonium chloride) by chain extension (coupling) with glycerol diglycidyl ether. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1068–1075, 2007
Effects of nanoparticles on the density reduction and cell morphology of extruded metallocene polyethylene/wood fiber nanocomposites
Authors: Guo G. , Wang K. H. , Park C. B. , Kim Y. S. , Li G.
Published: January 2007

This article investigates the effects of nanoparticles on cell morphology and foam expansion in the extrusion foaming of metallocene polyethylene/wood fiber nanocomposites with a chemical blowing agent. The results indicate that the addition of clay generally reduces the cell size, increases the cell density, and facilitates foam expansion. Furthermore, the foam material with added clay shows good char formation when it is burned. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1058–1063, 2007
Graft copolymerization of N‐vinyl‐2‐pyrrolidone onto sodium carboxymethylcellulose with azobisisobutyronitrile as the initiator
Authors: Yiğitoğlu Mustafa , Işıklan Nuran , Özmen Rukiye
Published: January 2007

Graft copolymers of sodium carboxymethylcellulose with N‐vinyl‐2‐pyrrolidone were prepared in aqueous solutions with azobisisobutyronitrile as the initiator. The graft copolymers [sodium carboxymethylcellulose‐g‐poly(N‐vinyl‐2‐pyrrolidone)] were characterized with Fourier transform infrared spectroscopy, elemental analysis, nuclear magnetic resonance spectroscopy, differential scanning calorimetry, and scanning electron microscopy. The grafting parameters, including the graft yield of the graft copolymer and the grafting efficiency of the reaction, were evaluated comparatively. The effects of reaction variables such as the time, temperature, and monomer and initiator concentrations on these parameters were studied. The graft yield and grafting efficiency increased and then decreased with increasing concentrations of N‐vinyl‐2‐pyrrolidone and azobisisobutyronitrile and increasing polymerization temperatures. The optimum temperature and polymerization time were 70°C and 4.30 h, respectively. Further changes in the properties of grafted sodium carboxymethylcellulose, such as the intrinsic viscosity, were determined. The overall activation energy for the grafting was also calculated to be 10.5 kcal/mol. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 936–943, 2007
Crosslinking of reactive α‐olefins and maleic anhydride copolymers as oil sorbers
Authors: Atta Ayman M. , El‐Hamouly Sabrnal H. , Al Sabagh Ahmed M. , Gabr Moataz M.
Published: January 2007

Octene (OC) and tetradecene (TD) monomers were copolymerized with maleic anhydride (MA) with a low conversion (<10% conversion) to determine their reactivity ratios. The monomers were copolymerized with different molar percentages of MA and OC or TD (90/10, 70/30, 50/50, and 10/90) with benzoyl peroxide as an initiator to produce MA/α‐olefin copolymers of different compositions. Fourier transform infrared was used to determine the copolymer compositions. The monomer reactivity ratios of the MA/OC and MA/TD copolymers were determined with the Fineman–Ross and Kelen–Tudos methods. Crosslinked MA/TD and MA/OC (50 : 50 mol/mol) copolymers were prepared by the condensation of the prepared linear copolymers with different glycols. The crosslinked copolymers were evaluated for oil absorbency applications. The effects of the glycol type, composition, crosslinker weight percentage, and type of oil on the swelling properties of the crosslinked polymers were studied with oil absorption tests. The swelling parameters, such as the maximum oil absorbency, characteristic oil absorbency, characteristic swelling time, and swelling rate constant, were evaluated for the synthesized sorbers. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 871–881, 2007
Nonisothermal crystallization kinetics of biodegradable poly(butylene succinate)/poly(vinyl phenol) blend
Authors: Qiu Zhaobin , Yang Wantai
Published: January 2007

Nonisothermal melt crystallization kinetics of biodegradable PBSU/PVPh blend was investigated with differential scanning calorimetry (DSC) from the viewpoint of practical application. PBSU/PVPh blends were cooled from the melt at various cooling rates ranging from 2.5 to 40°C/min. The crystallization peak temperature decreased with increasing the cooling rate for both neat and blended PBSU. Furthermore, the crystallization peak temperature of PBSU in the blend was lower than that of neat PBSU at a given cooling rate. Two methods, namely the Avrami equation and the Tobin method, were used to describe the nonisothermal crystallization of PBSU/PVPh blend. It was found that the Avrami equation was more suitable to predict the nonisothermal crystallization of PBSU/PVPh blend than the Tobin method. The effects of cooling rate and blend composition on the crystallization behavior of PBSU were studied in detail. It was found that the crystallization rate decreased with decreasing the cooling rate for both neat and blended PBSU. However, the crystallization of PBSU blended with PVPh was retarded compared with that of neat PBSU at the same cooling rate. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 972–978, 2007
Blend compatibility of waste materials—Cellulose acetate (from sugarcane bagasse) with polystyrene (from plastic cups): Diffusion of water, FTIR, DSC, TGA, and SEM study
Authors: Meireles Carla da Silva , Filho Guimes R. , de Assunção Rosana M. N. , Zeni Mara , Mello Kátia
Published: January 2007

In this article, the compatibility of blends produced from recycled materials—cellulose acetate (from sugarcane bagasse) and polystyrene (from plastic cups)—was studied using diffusion of water, Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and scanning electron microscopy. With these techniques, it was possible to confirm the existence of miscibility microregions in blends produced according to what has already been pointed out in a previous paper (Filho et al., J Appl Polym Sci 2005, 96, 516). In addition, all the results present a transition occurring in blends containing 30% polystyrene. This composition indicates the starting limit for a possible inversion between the matrix and the disperse phase in the system. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 909–914, 2007
Polylactide films formed by immersion precipitation: Effects of additives, nonsolvent, and temperature
Authors: Sawalha Hassan , Schroën Karin , Boom Remko
Published: January 2007

The influence of nonsolvent, crystallinity of the polymer film, and addition of dodecane (a poor solvent for the polymer and for the nonsolvent) on the morphology of polylactides films has been investigated and was related to phase separation behavior. Both amorphous poly‐DL‐lactide (PDLLA) and crystalline poly‐L‐lactide (PLLA) were dissolved in dichloromethane, and subsequently films were made by immersion in nonsolvent baths. PDLLA gave dense films without any internal structure, since the structure was not solidified by crystallization or glassification. PLLA films show varying structure depending on the nonsolvent. With methanol, asymmetric morphologies were observed as a result from combined liquid‐liquid demixing and crystallization, while with water symmetric spherulitic structures were formed. As a next step, dodecane was added, which is not miscible with the nonsolvent, and we found it to have a strong influence on the morphology of the films. The PDLLA films with dodecane did not collapse: a closed cell structure was obtained. In PLLA films, dodecane speeds up phase separation and induces faster crystallization in the films, and the porosity, size of the pores, and interconnectivity increased. When the PLLA solutions were subjected to a heat pretreatment, crystallization could be postponed, which yielded a cellular structure around dodecane, which did not contain spherulites anymore. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 959–971, 2007
Dispersed microfibril‐dominated deformation and fracture behaviors of linear low density polyethylene/isotactic polypropylene blends
Authors: Na Bing , Lv Ruihua , Zhao Zunxin
Published: January 2007

Linear low density polyethylene/isotactic polypropylene (LLDPE/iPP) blends, with oriented microfibrils of iPP dispersed in the nearly isotropic LLDPE matrix, has been prepared via melt extrusion drawing and subsequent thermal treatment at 160°C to melt LLDPE matrix. The presence of oriented microfibrils of iPP in the LLDPE/iPP blends not only promotes the homogenous deformation, with no drop of nominal stress around yield point, but also enhances the fracture toughness significantly. The specific Essential Work of Fracture we, which is a pure crack resistance parameter per ligament area unit, is 24.7 and 33.6 N/mm for the blends with 15 and 30 wt % microfibrils of iPP, respectively. Moreover, with the deduced deformation parameters, such as true yield stress and strain hardening modulus, the relationship between deformation parameters and fracture toughness is explored. It is demonstrated that the fracture toughness can be well correlated with the ratio of true yield stress to strain hardening modulus σty/G, and either a decrease in yield stress or an increase in strain hardening can improve fracture toughness. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1291–1298, 2007
Preparation and characterization core‐shell particles and application for E‐Ink
Authors: Wang Jing , Feng Ya‐qing , Guo Jun‐wei , Li Yu‐kun , Li Xiang‐gao
Published: January 2007

the core‐shell particles were prepared by dispersion copolymerization. The core‐shell particles were characterized with Fourier‐transform infrared spectroscopy, Transmission electron microscope and scanning electron microscope. The dispersion stability and electrophoretic performance of core‐shell particles were studied in the mixed medium of tetrachloroethylene and cyclohexance. Microcapsules containing the core‐shell particles were prepared by coacervation. Results showed that the core‐shell particles had good dispersion stability and it had no electric response, which could be used as grounding particles for E‐Ink. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1195–1199, 2007
Polymerization of methyl methacrylate catalyzed by macromolecule–copper (II) complex in sodium sulfite aqueous system
Authors: Qing‐Feng Xu , Jian‐Mei Lu , Xue‐Wei Xia , Meng Xiao , Li‐Hua Wang
Published: January 2007

Vinyl polymerization initiated by a copper complex immobilized on a novel polymer and characterization has been studied. Monomer, 4‐aldehyde‐3‐hydroxy phenyl acrylate (Ahpa), and its homopolymer, poly(4‐aldehyde‐3‐hydroxy phenyl acrylate) (PAhpa), were synthesized and characterized using IR, elemental analysis,1H NMR, TOF MS, etc. The side chain of the polymer can further coordinate with transition metal ions. Its polymeric Cu(II) complex in Na2SO3system is proved to be another useful catalyst in polymerization of methyl methacrylate (MMA) at room temperature. The obtained poly(methyl methacrylate) (PMMA) is similar to those determined by conventional free radical polymerization at the same conditions. Moreover, the catalytic mechanism studied was a “Coordination Hydrogen‐Transfer” process, which is different from that of CuCl2/Na2SO3system, but analogous with that of PVAm‐Cu(II)/Na2SO3(PVAm = polyvinylamine) system, was speculated and testified. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1285–1290, 2007
Reinforcement of the interface in drawn polymer blends PS/PA‐12
Authors: Miroshnikov Y. P. , Chaves G. A. , Vlasov S. V. , Gerasimov V. I.
Published: January 2007

The origin of the reinforcement effect in uniaxially drawn films on the basis of immiscible blends composed of crystalline matrix of polyamide‐12 (PA) and glassy polystyrene (PS) dispersed phase has been investigated. Other conditions being equal, the effect becomes the more pronounced the lager the draw ratio and the finer the PS dispersion. Since the latter factor is itself a strong function of phase viscosity ratio (μ), the following two techniques of adjusting the optimal value of μ ≈ 1 have been adopted. According to the first one, a selective plasticizer, which is a good solvent for the PS minor phase and a nonsolvent for the PA matrix phase, was added to the more viscous PS. According to the second approach, the value of μ was varied by the use of PS samples of different molecular weights. It was shown that significant reinforcement effect appears on drawing regardless of the method of adjusting optimal phase viscosity ratio. These data as well as the results obtained with the help of IR‐dichroism and transmission electron microscopy techniques evidence that the formation of a much more ordered crystalline morphology of the PA matrix located at the PS/PA interfaces and a large interface area are mainly responsible for the discussed reinforcement phenomenon. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1299–1305, 2007
Scale measurements as a conservation tool in endangered Zingel asper (Linnaeus, 1758)
Authors: Danancher D. , Labonne J. , Gaudin P. , Joly P.
Published: January 2007

Zingel asper (a percid) is a highly endangered endemic fish of the Rhone catchment (France). Scale reading was used to estimate age and growth rates in one of the two last remaining populations that are still present in relatively high densities (River Beaume).

Scale reading was validated for the first time in Z. asper by comparing back‐calculated lengths from scale annual increment to actual lengths obtained by individual mark–recapture monitoring. The impacts of age or sampling site on individual growth rates were explored using generalized linear models.

No major discrepancy was observed between actual and back‐calculated lengths. Longevity of Z. asper was inferred from the age data and did not exceed 3 years. Results showed variation in growth rates among ages (20 times higher for 1+ fish than for 2+ or 3+ fish) and also among sampling sites.

The present work provided the first estimates of annual growth rates in the Beaume population. This study also showed that scale reading allowed a valuable trade‐off between accuracy and conservation imperatives that often imply avoiding invasive techniques such as the implantation of passive integrative transponders.

Scale reading will be a valuable tool for future ecological studies in Z. asper and will help in developing conservation strategies for this species as longevity and growth patterns are two life‐history traits of major importance for the management of endangered populations.

Copyright © 2007 John Wiley & Sons, Ltd.
Optimization of bio‐hydrogen production from biodiesel wastes byKlebsiella pneumoniae
Authors: Liu Fei , Fang Baishan
Published: January 2007

Biodiesel wastes containing glycerol were utilized byKlebsiella pneumoniaeDSM 2026 to produce hydrogen. The optimization of medium components was performed using both Plackett‐Burman and uniform design methods. Using the Plackett‐Burman design, glycerol, yeast extract, NH4Cl, KCl and CaCl2 were found to be the most important components, which were further investigated by uniform design and second‐order polynomial stepwise regression analysis. The optimized medium containing 20.4 g·L‐1glycerol, 5.7 g·L‐1KCl, 13.8 g·L‐1NH4Cl, 1.5 g·L‐1CaCl2and 3.0 g·L‐1yeast extract resulted in 5.0‐fold increased level of hydrogen (57.6 mL/50 mL medium) production compared to initial level (11.6 mL/50 mL medium) after 24 h of fermentation The optimization of fermentation condition (pH, temperature and inoculum) was also conducted. When the strain grew in the optimized medium under optimal fermentation condition in a 5‐L stirred tank bioreactor for batch production, hydrogen yield and production reached 0.53 mol/mol and 117.8 mmol/L, respectively. The maximum hydrogen evolution rate was 17.8 mmol/(L·h). Furthermore, 1,3‐propanediol (6.7 g·L‐1) was also obtained from the liquid medium as a by‐product.
Enzymatic coating of lignocellulosic surfaces with polyphenols
Authors: Schroeder Marc , Aichernig Nina , Guebitz Georg M. , Kokol Vanja
Published: January 2007

Upgrading of the surface characteristics could enhance the bulk properties of naturally abundant fiber‐forming materials for better performance or create new value‐added products. Laccase can induce cross‐linkage and covalent coupling of low molecular weight compounds onto lignocellulosic surfaces. For this purpose the 38‐kDa laccase from Trametes hirsuta was purified and characterized. The best conditions for laccase‐induced coating of flax fibers were determined. This evaluation was based on the obtained coloration and color depth. A screening was carried out with different phenols for their potential as monomers for enzyme‐catalyzed polymerization resulting in a coating with antibacterial performance. While all the methoxyphenols showed different coloration with weak fastness properties, bacterial growth of Bacillus subtilis and Staphylococcus aureus was reduced significantly using ferulic acid and hydroquinone. Using laccase‐induced coupling and polymerization, multi‐functionality of the lignocellulosic surface, such as coloration and antimicrobial performance, was achieved, which depended on the nature of the applied phenolic monomer.
Molecular assembly formation of cyclic hexa‐β‐peptide composed of acetylated glycosamino acids
Authors: Hirata Tatsuya , Fujimura Futoshi , Horikawa Yoshiki , Sugiyama Junji , Morita Tomoyuki , Kimura Shunsaku
Published: January 2007

A novel cyclic hexamer of acetylated β‐glycosamino acid was synthesized and its conformation and molecular assembly formation was investigated. Variable temperature NMR study indicated that the cyclic hexapeptide took a C3 symmetric conformation at room temperature, but at elevated temperatures a C6 symmetric one, which was not due to averaging of the C3 symmetric conformation, appeared. Computational geometry optimization showed that the C6 symmetric conformation was a highly planar structure with amide groups orienting perpendicular to the ring plane. The cyclic hexa‐β‐peptide formed rod‐shaped crystals from an N,N‐dimethyl formamide solution at elevated temperature. The optical microscopy observation with a sensitive tint plate under cross‐nicol configuration and electron diffraction analysis of the crystals revealed that the cyclic hexa‐β‐peptides were stacked one after the other to form a regular nanotube structure. © 2007 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 88: 150–156, 2007.

This article was originally published online as an accepted preprint. The ‘Published Online’ date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
EZ‐Viz, a tool for simplifying molecular viewing in PyMOL
Authors: Grell Laura , Parkin Christopher , Slatest Len , Craig Paul A.
Published: January 2007

PyMOL is a molecular modeling program that can be used in a wide range of studies within the scientific community. Its ability to produce informative, detailed, stereoscopic images makes it a very powerful tool both in the laboratory and in the classroom. However, the PyMOL user interface is difficult to use, and the PyMOL User's Manual readily admits that “development has been focused on capabilities, not on ease‐of‐use for new users.” To resolve this, we set out to develop a new interface for PyMOL that helps eliminate the need for command line interactions, making it a much more user‐friendly interface. We have created a tabbed interface called EZ‐Viz, which contains a series of buttons and entry fields that allow users to select given attributes of a molecule and make changes to it by clicking a button as opposed to issuing highly syntactical commands. Other features of the interface include a Chime/PyMOL command converter, nine preset molecular views, four molecular movies, and molecular sequence and hetero atom information, all at the click of a button. The ongoing and continued development of EZ‐Viz could help to further the use of PyMOL, which we believe to be one of the most powerful molecular viewing programs currently available.
Analyzing ligand depletion in a saturation equilibrium binding experiment
Authors: Claro Enrique
Published: January 2007

I present a proposal for a laboratory practice to generate and analyze data from a saturation equilibrium binding experiment addressed to advanced undergraduate students. [3H]Quinuclidinyl benzilate is a nonselective muscarinic ligand with very high affinity and very low nonspecific binding to brain membranes, which contain a high density of muscarinic receptors. These features allow the instructor to devote especial emphasis to evaluate ligand depletion, and therefore, stress the subtle but fundamental difference between total (added) ligand and free ligand concentration at equilibrium.