bluuebunny/crossref_metadata_2025 huggingface dataset:
Poverty and pastoral counselling: Design for an extensive research project
Authors: Janse van Rensburg Johan
Published: November 2009

Poverty is arguably the most common and devastating social disease in the world. It is not, however, only a social, political or economic problem. Knowing how to respond to the calling of caring for the poor is an incredible charge for the church. It is not only a matter of Christian charity but also a matter of pastoral care. Extensive research on such a phenomenon needs careful planning and precise execution. It was therefore decided to conduct participatory action research with informed researchers. It is hoped that the input of these informed participators will help the researcher to design a methodology that will be able to dig deeper than the surface of the problem and to uncover the most important driving forces and basic needs of poverty. This article serves as an introduction to a four-year research project on poverty, financially supported by a generous bursary from the National Research Fund.
The importance of fallback foods in primate ecology and evolution
Authors: Constantino Paul J. , Wright Barth W.
Published: November 2009

The role of fallback foods in shaping primate ranging, socioecology, and morphology has recently become a topic of particular interest to biological anthropologists. Although the use of fallback resources has been noted in the ecological and primatological literature for a number of decades, few attempts have been made to define fallback foods or to explore the utility of this concept for primate evolutionary biologists and ecologists. As a preface to this special issue of the American Journal of Physical Anthropology devoted to the topic of fallback foods in primate ecology and evolution, we discuss the development and use of the fallback concept and highlight its importance in primatology and paleoanthropology. AmJ Phys Anthropol 140:599–602, 2009. © 2009 Wiley‐Liss, Inc.
Fallback foods of temperate‐living primates: A case study on snub‐nosed monkeys
Authors: Grueter Cyril C. , Li Dayong , Ren Baoping , Wei Fuwen , Xiang Zuofu , van Schaik Carel P.
Published: November 2009

Only a few primate species thrive in temperate regions characterized by relatively low temperature, low rainfall, low species diversity, high elevation, and especially an extended season of food scarcity during which they suffer from dietary stress. We present data of a case study of dietary strategies and fallback foods in snub‐nosed monkeys (Rhinopithecus bieti) in the Samage Forest, Northwest Yunnan, PRC. The snub‐nosed monkeys adjusted intake of plant food items corresponding with changes in the phenology of deciduous trees in the forest and specifically showed a strong preference for young leaves in spring. A non‐plant food, lichens (Parmeliaceae), featured prominently in the diet throughout the year (annual representation in the diet was about 67%) and became the dominant food item in winter when palatable plant resources were scarce. Additional highly sought winter foods were frost‐resistant fruits and winter buds of deciduous hardwoods. The snub‐nosed monkeys' choice of lichens as a staple fallback food is likely because of their spatiotemporal consistency in occurrence, nutritional and energetic properties, and the ease with which they can be harvested. Using lichens is a way to mediate effects of seasonal dearth in palatable plant foods and ultimately a key survival strategy. The snub‐nosed monkeys' fallback strategy affects various aspects of their biology, e.g., two‐ and three‐dimensional range use and social organization. The higher abundance of lichens at higher altitudes explains the monkeys' tendency to occupy relatively high altitudes in winter despite the prevailing cold. As to social organization, the wide temporal and spatial availability of lichens strongly reduces the ecological costs of grouping, thus allowing for the formation of “super‐groups.” Usnea lichens, the snub‐nosed monkeys' primary dietary component, are known to be highly susceptible to human‐induced environmental changes such as air pollution, and a decline of this critical resource base could have devastating effects on the last remaining populations. Within the order Primates, lichenivory is a rare strategy and only found in a few species or populations inhabiting montane areas, i.e., Macaca sylvanus, Colobus angolensis, and Rhinopithecus roxellana. Other temperate‐dwelling primates rely mainly on buds and bark as winter fallback foods. Am J Phys Anthropol 140:700–715, 2009. © 2009 Wiley‐Liss, Inc.
Defining fallback foods and assessing their importance in primate ecology and evolution
Authors: Marshall Andrew J. , Boyko Corin M. , Feilen Katie L. , Boyko Ryan H. , Leighton Mark
Published: November 2009

Physical anthropologists use the term “fallback foods” to denote resources of relatively poor nutritional quality that become particularly important dietary components during periods when preferred foods are scarce. Fallback foods are becoming increasingly invoked as key selective forces that determine masticatory and digestive anatomy, influence grouping and ranging behavior, and underlie fundamental evolutionary processes such as speciation, extinction, and adaptation. In this article, we provide an overview of the concept of fallback foods by discussing definitions of the term and categorizations of types of fallback foods, and by examining the importance of fallback foods for primate ecology and evolution. We begin by comparing two recently published conceptual frameworks for considering the evolutionary significance of fallback foods and propose a way in which these approaches might be integrated. We then consider a series of questions about the importance of fallback foods for primates, including the extent to which fallback foods should be considered a distinct class of food resources, separate from preferred or commonly eaten foods; the link between life history strategy and fallback foods; if fallback foods always limit primate carrying capacity; and whether particular plant growth forms might play especially important roles as fallback resources for primates. We conclude with a brief consideration of links between fallback foods and primate conservation. Am J Phys Anthropol 140:603–614, 2009. © 2009 Wiley‐Liss, Inc.
Thermal and mechanical properties of photocured organic–inorganic hybrid nanocomposites of terpene‐based acrylate resin and methacrylate‐substituted polysilsesquioxane
Authors: Ando Shingo , Someya Yoshihiro , Takahashi Tsutomu , Shibata Mitsuhiro
Published: November 2009

Diacrylate compounds derived from α‐pinene and limonene (TDAs: TDA‐1 and TDA‐2) were photocured with methacryl‐substituted polysilsesquioxane (ME‐PSQ) prepared from 3‐(trimethoxysilyl)propyl methacrylate and tetramethylammonium hydroxide (TMAOH) in the TDA/ME‐PSQ weight ratio of 20 : 0, 20 : 1, 20 : 2, 20 : 3, and 20 : 4. All the photocured TDA/ME‐PSQ hybrid nanocomposites became transparent. The thermomechanical analysis of the cured TDA/ME‐PSQ revealed that the glass transition temperature (Tg) increased, the thermal expansion coefficient above Tg decreased with increasing ME‐PSQ content, and that the TDA‐1/ME‐PSQ had ca. 30°C greater Tg than the TDA‐2/ME‐PSQ with the same ME‐PSQ content. Also, the dynamic mechanical analysis revealed that the TDA‐1/ME‐PSQ had much greater storage modulus at around 150°C than the corresponding TDA‐2/ME‐PSQ. The flexural strength and modulus of the TDA/ME‐PSQ nanocomposites at 20°C had maximum at ME‐PSQ content 4.8 and 13.0 wt %, respectively. As a whole, the thermal and mechanical properties of the nanocomposites were improved by the addition of ME‐PSQ, and those of TDA‐1/ME‐PSQ nanocomposites were superior to those of TDA‐2/ME‐PSQ. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Flammability and thermal degradation of epoxy acrylate modified with phosphorus‐containing compounds
Authors: Chen Xilei , Song Lei , Hu Yuan
Published: November 2009

A series of UV‐curable flame‐retardant resins was obtained by blending phosphate acrylate (BTP) in different ratios with epoxy acrylate resin (EA). The flammability was characterized by limiting oxygen index (LOI), UL 94 flammability rating and cone calorimeter, and the thermal degradation of the flame‐retardant resins was studied using thermo gravimetric analysis (TGA), and real‐time Fourier transform infrared (RTFTIR). The results indicated that the flame‐retardant efficiency increases with the addition of BTP. The heat release rate with the addition of BTP decreases greatly. The TGA data showed that EA/BTP blends have lower initial decomposition temperatures and higher char residues than pure EA, whereas BTP has the lowest initial decomposition temperature and the highest char residue. The RTFTIR study indicates that the EA/BTP blends have lower thermal oxidative stability than the pure EA. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of solvent on surface wettability of electrospun polyphosphazene nanofibers
Authors: Lin Yi‐Jun , Cai Qing , Li Qi‐Fang , Xue Li‐Wei , Jin Ri‐Guang , Yang Xiao‐Ping
Published: November 2009

Two kinds of biodegradable polymers, poly(ε‐caprolactone) (PCL) and poly[(alanino ethyl ester)0.67 (glycino ethyl ester)0.33 phosphazene] (PAGP), were electrospun by using four different solvents. All PCL nanofibrous mats had similar surface water contact angles independent of solvents. However, it was found that the water contact angles of PAGP nanofibrous mats were 102.2° ± 2.3°, 113.5° ± 2.2°, 115.8° ± 1.4°, and 119.1° ± 0.7°, respectively, when trifluoroethanol, chloroform, dichloromethane, and tetrahydrofuran were used as a solvent. This difference was supposed mainly due to phosphorous and nitrous atoms in PAGP being dragged to fiber surface with solvent evaporation during the solidification of nanofibers, because of the strong interaction between positive phosphorous atoms and electronegative atoms in solvents. This interaction was confirmed by Fourier Transform Infrared, and the accumulation of phosphorous and nitrous atoms in the solvent‐casting PAGP film surface was identified by X‐ray photoelectron spectrometry analysis. PCL samples did not show the solvent‐controlled surface wettability because it contained fewer polar atoms. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
The structure change of dynamically fatigued unfilled natural rubber vulcanizates
Authors: Zhang Ping , Shi Xinyan , Li Junge , Yu Guangshui , Zhao Shugao
Published: November 2009

The submicrostructure of dynamically fatigued unfilled natural rubber vulcanizates was investigated by using scanning electron microscope (SEM) and atomic force microscope (AFM). AFM photographs showed the sample surface roughness became worse after tensile fatigue and the largest surface undulation was as twice that of the unfatigued sample. SEM photographs showed that many micropores of 101–102 nm, a sort of defect, occurred on the cross section of samples after tensile fatigue. The surface roughness became weaker and the size of the micropore was reduced to a few to dozens of nanometers with the addition of antiaging agent N‐(1,3‐dimethyl butyl butyl)‐N′‐phenyl‐p‐phenylene diamine (4020); furthermore, the mechanical properties and dynamic viscoelastic properties in the later period of fatigue changed much. E′ decreased greatly and tan δ increased obviously with the extension of fatigue. It indicated that 4020 was only effective in the early period of tensile fatigue.© 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of polymer solution concentration on the swelling and mechanical properties of glycol chitosan superporous hydrogels
Authors: Park Joohyang , Kim Dukjoon
Published: November 2009

This study examined the effect of the polymer solution concentration on the swelling and mechanical properties of glycol chitosan (GCS) superporous hydrogels (SPHs). GCS SPHs were synthesized using a gas blowing method using glyoxal as the crosslinking agent at different polymer solution concentrations. A small change in the GCS solution concentration resulted in a remarkable change in compression strength and swelling kinetics without any significant loss in equilibrium water imbibing capacity. The increase in mechanical strength accompanied by the decrease in swelling kinetics was caused by the generation of smaller pores during the gelation process of the reactant systems associated with a higher polymer solution viscosity. The apparent diffusion coefficients for a variety of GCS/simulated gastric fluid solution systems were determined from the theoretical fitting of experimental dynamic swelling data, explaining the effects of the solution concentration and crosslinking density on the swelling kinetics. The diffusion coefficients determined in this study are expected to be used as the basic information in estimating the swelling kinetics of samples in different dimension. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation and properties of chlorosulfonated polyethylene/organomontmorillonite nanocomposites
Authors: Gu Zheng , Song Guojun , Liu Weisheng , Gao Jianming , Dou Wei , Lu Ping
Published: November 2009

Chlorosulfonated polyethylene (CSPE)/organomontmorillonite (OMMT) nanocomposites were prepared by a melt intercalation method. The microstructure of the nanocomposites was characterized by transmission electron microscopy and X‐ray diffraction. The effects of the OMMT content on the mechanical properties and swelling behavior of the nanocomposites were investigated. The improvement in the thermal stability of the nanocomposites was determined by thermogravimetric analysis. Transmission electron microscopy and X‐ray diffraction showed that CSPE was intercalated into OMMT. When the OMMT content was lower than 12 wt %, the nanocomposites showed excellent tensile properties, which was attributed to nanometer‐scale dispersion. The introduction of a small amount of OMMT also improved the thermal stability and swelling behavior, which was attributed to the gas barrier action of the OMMT layers. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effects of rice husk (RH) particle size, glass fiber (GF) length, RH/GF ratio, and addition of coupling agent on the mechanical and physical properties of polypropylene‐RH‐GF hybrid composites
Authors: Rozman H. D. , Zuliahani A. , Tay G. S.
Published: November 2009

Polypropylene (PP) hybrid composites based on rice husk (RH) with different particle size and glass fiber (GF) with different length were prepared. The composites were subjected to mechanical and water immersion tests. From the results obtained, it was found that the mechanical properties of the hybrid composites were strongly dependent on the size of RH particle and length of GF. It could be further enhanced with the presence of coupling agent. In this study, two types of coupling agents, i.e., Epolene E‐43 (E‐43) and 3‐(trimethoxysilyl)‐propylmethacrylate (TPM), were employed. In general, E‐43 imparted significant improvement in the mechanical properties. From the water immersion results, it was found that the hydrophobicity of the composites was increased with the presence of coupling agent. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect on rebinding behavior with different composition and structure of the dually imprinted alginate polymer microspheres using proteins and o/w emulsion drops as dual templates
Authors: Ying Xiaoguang , Zhang Fengju , Zhang Liguang , Cheng Guoxiang
Published: November 2009

In this study, the dually imprinted alginate polymer microspheres are prepared using proteins and o/w emulsion drops as dual templates with different structure and composition such as the content of hydroxylethyl cellulose (HEC), crosslinking degree, and porous size, etc. The rebinding tests are carried on egg white albumin (EA) protein imprinted alginate polymer microspheres with interpenetrating networks (IPNs) under various conditions like ionic strength, temperature, protein concentration, and pH value. Results showed that the IPNs with alginate and HEC by covalent bond influence the rigidity and swelling properties. Porous structure formed by introducing emulsion drops into alginate hydrogel has effect on the permeability and specific surface area of the polymer microspheres. The variation rule of rebinding behavior according to different HEC content and pore diameters reveals macromolecular imprinting effect to be different with pure pore creating effect compared with the emulsion imprinting effect. Moreover, the macromolecular and emulsion dually imprinting‐rebinding tests verify the co‐existing macromolecular imprinting effect and pore creating effect of emulsion imprinting. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Blends of poly(2,6‐dimethyl‐1,4‐phenylene oxide)/polyamide 6 toughened by maleated polystyrene‐based copolymers: Mechanical properties, morphology, and rheology
Authors: Li Bo , Wan Chaoying , Zhang Yong , Ji Jiliang
Published: November 2009

Poly(2,6‐dimethyl‐1,4‐phenylene oxide)/polyamide 6 (PPO/PA6 30/70) blends were impact modified by addition of three kinds of maleated polystyrene‐based copolymers, i.e., maleated styrene‐ethylene‐butylene‐styrene copolymer (SEBS‐g‐MA), maleated methyl methacrylate‐butadiene‐styrene copolymer (MBS‐g‐MA), and maleated acrylonitrile‐butadiene‐styrene copolymer (ABS‐g‐MA). The mechanical properties, morphology and rheological behavior of the impact modified PPO/PA6 blends were investigated. The selective location of the maleated copolymers in one phase or at interface accounted for the different toughening effects of the maleated copolymer, which is closely related to their molecular structure and composition. SEBS‐g‐MA was uniformly dispersed in PPO phase and greatly toughened PPO/PA6 blends even at low temperature. MBS‐g‐MA particles were mainly dispersed in the PA6 phase and around the PPO phase, resulting in a significant enhancement of the notched Izod impact strength of PPO/PA6 blends from 45 J/m to 281 J/m at the MBS‐g‐MA content of 20 phr. In comparison, the ABS‐g‐MA was mainly dispersed in PA6 phase without much influencing the original mechanical properties of the PPO/PA6 blend. The different molecule structure and selective location of the maleated copolymers in the blends were reflected by the change of rheological behavior as well. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation and characterization of a polycaprolactone/C60 composite and its improved counterpart (PCLNH2/C60OH)
Authors: Wu Chin‐San
Published: November 2009

In this study, polycaprolactone/C60 (PCL/C60) hybrids were prepared via a melt‐blending method. To enhance the compatibility between PCL and C60, the acrylic acid‐grafted polycaprolactone (PCL‐g‐AA) was first transformed to PCLNH2 by mixing with 1,6‐diaminohexane, while C60 was oxidized using a mixture of H2SO4/HNO3 and NaOH to derive C60 fullerol (C60OH). Thereafter, C60OH and PCLNH2 were used to replace PCL and C60, respectively. The resulting products were characterized using FTIR, solid‐state 13C‐ and 1H‐ NMR, TGA, DMA, SEM, TEM, and Instron mechanical testing. Because of the formation of NHCO groups through the reaction between amino groups of PCLNH2 and hydroxyl groups of C60OH, thermal and mechanical properties of the PCLNH2/C60OH composite were significantly superior to those of PCL/C60. The optimal blend was the 5 wt % C60OH with PCLNH2, producing an 84°C increase in initial decomposition temperature (IDT). C60OH in excess of 5 wt % aggregated and caused separation of the organic and inorganic phases, lowering their compatibility.© 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Quantitative analysis for reaction between epoxidized natural rubber and poly (L‐lactide) through 1H‐NMR spectroscopy
Authors: Saito Takayuki , Klinklai Warunee , Yamamoto Yoshimasa , Kawahara Seiichi , Isono Yoshinobu , Ohtake Yoshito
Published: November 2009

Reaction between epoxidized natural rubber and poly(L‐lactide) (PLLA) was investigated quantitatively in terms of conversion of the epoxidized natural rubber. The epoxidized natural rubber was prepared by epoxidation of high ammonia natural rubber (HA‐NR) or deproteinized natural rubber (DPNR) with peracetic acid followed by depolymerization with ammonium persulfate. The resulting liquid HA‐NR having epoxy group (LENR) or liquid DPNR having epoxy group (LEDPNR) were subjected to heating at 473 K for 20 min, after blending with PLLA. The products were characterized through morphology observation, DSC measurement, and 1H‐NMR spectroscopy. The conversions of the rubbers were estimated from intensity ratio of signals in 1H‐NMR spectrum for the products after removing unreacted rubber with toluene. Difference in the estimated conversion between the LENR/PLLA and LEDPNR/PLLA blends was interpreted in relation to proteins present in the rubber. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Polypropylene nanocomposite film: A critical evaluation on the effect of nanoclay on the mechanical, thermal, and morphological behavior
Authors: Sharma S. K. , Nema Ajay K. , Nayak S.K.
Published: November 2009

Polypropylene (PP)/clay nanocomposites prepared by melt blending technique using different percentages of clay with and without maleic anhydride grafted PP (MA‐PP) were studied. The intercalated and exfoliated structure of nanocomposites was characterized by X‐Ray Diffraction (XRD) and transmission electron microscopy (TEM). Because of the typical intercalated and exfoliated structure, the tensile modulus of the nanocomposites were improved significantly as compared to virgin PP. The viscoelastic behavior of the nanocomposites was studied by dynamical mechanical analysis (DMA) and the results showed that with the addition of treated clay to PP there was substantial improvement in storage modulus increases. The thermal stability and crystallization of the PP nanocomposites as studied by differential scanning calorimeter (DSC) and thermo gravimetric analysis (TGA) were also improved significantly compared to PP. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Celite‐mediated linking of polyurethane block copolymers and the impact on the shape memory effect
Authors: Chung Yong‐Chan , Chun Byoung Chul , Lee Sang Do , Park Jong Shin
Published: November 2009

Celite, a porous inorganic material with enormous surface area and hydroxyl groups on the surface, was used as a cross‐linker of polyurethane (PU) copolymer chains to improve its shape memory and mechanical properties. PU copolymers with different Celite contents were prepared and characterized by IR, DSC, and universal testing machine. The glass transition temperature of PU copolymers was maintained around 20°C independent of Celite content. The shape memory and mechanical properties were dependent on when Celite was added during the polymerization reaction. The reaction in which Celite was added at the middle stage of polymerization showed the best shape memory and mechanical properties. The best shape recovery of PU was found at 0.3 wt % Celite and increased to 97% even after the third cycle. Likewise, the shape retention also maintained a remarkable 86% after three cycles. The reasons underlining the high shape recovery and shape retention by adopting Celite as a cross‐linker are discussed in this article. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Low percolation threshold and high conductivity in carbon black filled polyethylene and polypropylene composites
Authors: Yuan Qiang , Wu Dongyang
Published: November 2009

High electrically conductive composites have been manufactured using twin and single screw extruders from carbon black with polyolefin. High density, low density polyethylene, polypropylene, polyethylene/polypropylene copolymer, and maleic anhydrite grafted polypropylene have been compounded with three carbon blacks (CBs), i.e., Black Pearl, Printex, and Ketjen, respectively. The lowest percolation threshold (0.8 vol %) for conductive composite was obtained using Ketjen CB blended with high density polyethylene (HD3690, MFI = 36 g/10 min). Polypropylene composites also achieved low percolation thresholds of 1.5 vol % when compounded with Printex or Ketjen CB. Decreasing melt viscosity of polymer matrix resulted in decreasing resistivity of composites. Ketjen CB showed the best conductive behavior for both polyethylene and polypropylene composites. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Compressible magnetorheological fluids
Authors: Fuchs Alan , Rashid Abu , Liu Yanming , Kavlicoglu Barkan , Sahin Huseyin , Gordaninejad Faramarz
Published: November 2009

A novel compressible magnetorheological fluid (CMRF) has been synthesized with additives that provide compressibility to the fluid. This CMRF has been designed to provide an elastic component to a magnetorheological fluid (MRF) that can be used as a springless damper. CMRF provides controllable compressibility to the MRF. The controllability of the fluid is achieved by the use of magnetic particles and an external magnetic field, and the fluid is made compressible by the addition of suspended compressible polymer particles. The compressibility of the fluid has been characterized with force–displacement measurements. This CMRF has controllable off‐state viscosity and high shear yield stress. The incorporation of polymeric particles into the MRF also decreases the settling of iron particles and improves the redispersion of the fluid. To make the fluid more redispersible, the surface of the iron particles is coated with a high‐temperature fluorinated polymer. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Radiation‐induced polymerization of butyl acrylate for recovery of organic solvents
Authors: Kattan M. , Al‐Kassiri H.
Published: November 2009

Radiation‐induced polymerization of butyl acrylate using 60Co gamma rays has been investigated under different conditions, such as irradiation dose (0–130 kGy), dose rate (10 kGy/h), and temperature (25–70°C). A linear relationship between conversion and temperature of irradiation was found. The activation energy (E) of 9.37 kJ/mol was obtained from kinetic analysis of the result from the polymerization at 10 kGy/h. Thermal properties were examined using differential scanning calorimetry and thermal gravimetric analysis. Efficient extraction of organic solvents including chloroform, chlorobenzene, carbon tetrachloride, benzene, styrene was revealed by the swelling and releasing measurements. These results indicate the feasibility of applying this polymer, which was prepared by radiation‐induced polymerization, to management of organic wastes in the field of environment. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Rheology of poly(vinyl chloride) plastisol for superhigh shear‐rate processing. I
Authors: Nakajima N. , Harrell E. R.
Published: November 2009

In coating operations with poly(vinyl chloride) plastisol, there is a high shear limit because the flow becomes unstable. However, there is an indication that the flow becomes stable at superhigh shear rates well past the unstable region. This article explores the effect of the particle size (with a similar size distribution spread) and the effect of the amount of the emulsifier on the flow at superhigh shear rates. It has been known that below the flow instability, larger particles lead to a lower viscosity, and an increased amount of the emulsifier leads to a higher viscosity. The question is whether or not the same trends persist at superhigh shear rates. Observations in this study confirm these trends. In addition, the emulsifier has been found to enhance the interparticle attraction. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis and characterization of new polyurethane based on polycaprolactone
Authors: Maafi El Miloud , Malek Fouad , Tighzert Lan
Published: November 2009

Different polyurethane (PU) were synthesized from ε‐polycaprolactone diol, 4,4′‐diphenyl methane diisocyanate (MDI) and bis(2‐hydroxyethyl)terephthalate (BHET), using a two‐step method and a one‐step method providing regular and random distributions of starting monomers in the PU chains. Even with an identical molar monomer composition, the properties of obtained PU are different depending on the method of synthesis. The structure of PU was characterized by 1H and 13C‐NMR and Fourier transform infrared spectroscopy (FTIR). The thermomechanical properties of synthesized PU were also studied demonstrating the influence of aromatic ring in the macromolecular chain. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Improvement of nanoclays dispersion through microwave processing in polyurethane rigid nanocomposite foams
Authors: Lorenzetti A. , Hrelja D. , Besco S. , Roso M. , Modesti M.
Published: November 2009

Polyurethane rigid nanocomposite foams were synthesized by in situ‐polymerization using both pristine and organically modified layered silicates. The effect of synthesis conditions, in particular the effect of different dispersing techniques, on morphology and mechanical properties of polyurethane nanocomposite foams was studied. To promote dispersion, clays were dispersed either in polyols or isocyanate and were subjected to a well known dispersion method, like ultrasonication, but also to a new dispersion method, based on microwaving. The morphological characterization of the foams, carried on using X‐ray diffraction, scanning electron microscopy, and transmission electron microscopy, proved that the technology based on microwave processing is able to provide very good silicates dispersion and requires very short application time to be effective. Further confirmations of the importance of the clay organo‐modifier are still present. Mechanical characterization of foams show that clay interferes with H‐bond formation and then the overall compressive performance of PU nanocomposite foams depends on the competition between the positive reinforcing effect of clay and the negative effect on H‐bond formation. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Two‐stage grafting onto polyethylene fiber by radiation‐induced graft polymerization and atom transfer radical polymerization
Authors: Komatsu Makoto , Kawakami Takashi , Kanno Jun‐Ichi , Sasaki Takeo
Published: November 2009

Two‐stage graft polymerization onto polyethylene (PE) fiber was demonstrated. The graft side chain was formed by radiation‐induced graft polymerization. A PE fiber was irradiated with an electron beam and immersed in a vinyl monomer solution. The terminal of the formed graft chain was halogenated using N‐bromosuccinimide. The halogenated graft chain was then extended by atom transfer radical polymerization to obtain block‐copolymer grafted PE fibers. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Reduction of surface friction of natural rubber film coated with PMMA particle: Effect of particle size
Authors: Anancharungsuk Waranya , Taweepreda Wirach , Wirasate Supa , Thonggoom Rattaporn , Tangboriboonrat Pramuan
Published: November 2009

The friction coefficient of the sulphur‐prevulcanized natural rubber (SPNR) film could be effectively reduced by deposition of poly(methyl methacrylate) (PMMA) particles. The nanoscale surface roughness of rubber, determined by atomic force microscope, was directly proportional to the particle size of PMMA particle at 12% surface coverage (Cs). The %Cs and surface roughness of the modified SPNR increased, while the friction coefficient decreased, with increasing PMMA latex concentration and immersion time. By using a mixture of latexes having both large and small sizes, the increase in the amount of small particles resulted in the better distribution of large particles deposited on the rubber surface. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Compatibilization and development of layered silicate nanocomposites based of unsatured polyester resin and customized intercalation agent
Authors: Torre Luigi , Chieruzzi Manuela , Kenny Josè M.
Published: November 2009

In this study a procedure for the preparation of compatibilized nanoclays was used to produce effective nanocomposites based on unsatured polyester (UP) resin. A compatibilization procedure of the filler with a selected surfactant has been developed and optimized, the effect of organic modifiers on the synthesized nanocomposites properties was studied. Moreover, polyester/clay nanocomposites were prepared. In particular, samples were prepared using two different mixing methods. The properties and formation processes of the nanocomposites obtained using the two methods were compared. X‐ray diffraction studies revealed the formation of intercalated/exfoliated nanocomposites structures. The effect of processing parameters, used for both the compatibilization procedure and the preparation of nanocomposites, was studied. Dynamic mechanical, thermal analysis, and rheological tests were performed to investigate the formation mechanism of UP/montmorillonite nanocomposite. In particular, mechanical properties of nanocomposites were studied using dynamic mechanical analysis and tensile tests. Mechanical, rheological, and thermal characterization have confirmed the validity of the used approach to compatibilize the nanoclay and to produce nanocomposites. Tensile strength and Young's modulus were modified by the loading of the organoclays. Furthermore, the rheology of the nanocomposite formulation provided processing information, while mechanical and dynamic mechanical characterization was performed on the nanocomposites produced with the newly compatibilized formulation. The results have shown that nanocomposites with better mechanical properties can be obtained through the selection of an appropriate compatibilization process. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation and characterization of novel hybrid of bio‐assisted mineralized Zn‐Al layered double hydroxides using chitosan as a template
Authors: Depan Dilip , Singh Raj Pal
Published: November 2009

The purpose of this study was to prepare and characterize a novel nanohybrid prepared from the template‐assisted mineralization of Zn‐Al Layered Double Hydroxide (LDH) onto the surface of Chitosan (CSI), with an emphasis on morphology, biocompatibility, and its use as an efficient drug carrier agent. The as prepared LDH is highly crystalline, with platelet‐like morphology and curved tactoids when nucleated onto the surface of CSI. Our results indicate that the OH and NH functional moieties on CSI can direct an ordered structure of LDH, due to the electrostatic interaction between biopolymer and inorganic lamellae. We have been successful to intercalate an anti‐inflammatory drug, Sodium Ibuprofen (Ibu), into LDH, through conventional coprecipitation method. LDHs are endowed with great potential for delivery vector because their stacked layers lead to safe reservation of biofunctional molecules or genes, and their ion exchangeability and solubility in acidic media (pH < 4) give rise to the controlled release of drug molecules. According to the cell‐growth studies, LDHs are found as cell viable up to the concentration of 500 μg/mL. This study reveals that LDH not only plays a role of a biocompatible‐delivery matrix but also facilitates a significant increase in the delivery efficiency. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
The effect of ram‐pressure stripping and starvation on the star formation properties of cluster galaxies
Authors: Boselli A. , Boissier S. , Cortese L. , Gavazzi G.
Published: November 2009

We have combined UV to radio centimetric observations of resolved galaxies in the Virgo cluster with multizone, chemospectrophotometric models of galaxy evolution especially tailored to take into account the effects of the cluster environment (ram pressure stripping and starvation). This exercise has shown that anemic spirals with truncated radial profiles of the gas component and of the young stellar populations, typical in rich clusters of galaxies, have been perturbed by a recent (∼100 Myr) ram pressure stripping event induced by their interaction with the cluster intergalactic medium. Starvation is not able to reproduce the observed truncated radial profiles. Both ram pressure and starvation induce a decrease of the stellar surface brightness of the perturbed disc, and thus can hardly be invoked to explain the formation of lenticular galaxies inhabiting rich clusters, which are characterised by higher surface brightnesses than early type spirals of similar luminosity. In dwarfs the ram pressure stripping event is so efficient to totally remove their gas thus stopping on short time scales (<2 Gyr) their star formation activity. Low luminosity star forming discs can be transformed in dE galaxies (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cool gas accretion, thermal evaporation, and quenching of star formation in elliptical galaxies
Authors: Nipoti C.
Published: November 2009

The most evident features of colour‐magnitude diagrams of galaxies are the red sequence of quiescent galaxies, extending up to the brightest elliptical galaxies, and the blue cloud of star‐forming galaxies, which is truncated at a luminosity L ∼ L*. The truncation of the blue cloud indicates that in the most massive systems star formation must be quenched. For this to happen the virial‐temperature galactic gas must be kept hot and any accreted cold gas must be heated. The elimination of accreted cold gas can be due to thermal evaporation by the hot interstellar medium, which in turn is prevented from cooling by feedback from active galactic nuclei (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The effect of clouds on the dynamical and chemical evolution of gas‐rich dwarf galaxies
Authors: Recchi S. , Hensler G.
Published: November 2009

We study the effects of clouds on the dynamical and chemical evolution of gas‐rich dwarf galaxies, in particular focusing on two model galaxies similar to IZw18 and NGC 1569. We consider both scenarios, clouds put at the beginning of the simulation and continuously created infalling ones. Due to dynamical processes and thermal evaporation, the clouds survive only a few tens of Myr, but during this time they act as an additional cooling agent and the internal energy ofcloudy models is typically reduced by 20–40% in comparison with models without clouds. The clouds delay the development of large‐scale outflows, therefore helping to retain a larger amount of gas inside the galaxy. However, especially in models with continuous creation of infalling clouds, their bullet effect can pierce the expanding supershell and create holes through which the superbubble can vent freshly produced metals. Moreover, assuming a pristine chemical composition for the clouds, their interaction with the superbubble dilutes the gas, reducing the metallicity (by up to ∼0.4 dex) with respect to the one attained by diffuse models (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Probing evolutionary mechanisms in galaxy clusters: H I in Abell 1367
Authors: Scott T.C. , Bravo‐Alfaro H. , Brinks E. , Cortese L. , Boselli A.
Published: November 2009

We are carrying out a programme of CO and interferometric H I observations in the nearby galaxy cluster Abell 1367. The aim is to better understand the processes driving the evolution of the ISM in late‐type galaxies in the cluster environment. Abell 1367 is a dynamically young cluster. We have determined the H I content and g – i colour from AGES (Cortese 2008) and SDSS, respectively, of its bright late‐type galaxies (spirals) in a volume centred on the NW subcluster. We use a combination of these characteristics, both of which are indicative of evolutionary history, to classify each spiral into one of four evolutionary states. This analysis revealed the cluster contains spirals in a wide range of evolutionary states. VLA D‐array imaging centred on the NW subcluster indicates most galaxies in that field have their H I intensity maximum offset relative to its optical counterpart, implying a recent and strong disturbance. The direction of this offset is not always consistent with a simple scenario of ram pressure stripping by the cluster's high density intra‐cluster medium (ICM) (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
SCG0018‐4854: A young and dynamic compact group
Authors: Presotto V. , Temporin S. , Pompei E. , Iovino A.
Published: November 2009

It is widely recognized in the literature that processes taking place within the group environment are among the main drivers of galaxy evolution. SCG0018‐4854 is a compact group of galaxies located at a distance of v ∼ 3200 km s–1. It is composed of four galaxy members, very close to each other on the sky: their median projected distance is only ∼20 Kpc (H = 70 km s–1Mpc–1). The remarkably high local galaxy density coupled with the low velocity dispersion (∼100 km s–1) characterizing this group, makes SCG001 8‐4854 a test case to study in detail the interplay between the environment and the galaxy properties. We present here some of the properties of the group members that are related to their mutual interaction, as derived from our kinematical and morphological analysis (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Smooth, undisturbed dwarf spheroidal galaxies in the Perseus cluster core: Implications for dark matter content
Authors: Penny Sj. , Conselice Cj. , De Rijcke S. , Held E.V.
Published: November 2009

Using deep HST/ACS observations of the core of the Perseus Cluster, we identify a large population of dwarf elliptical galaxies down to MV = –12. All these dwarfs are remarkably smooth in appearance, showing no evidence for internal features that could be the result of tidal processes or star formation induced by the cluster potential. Based on these observations and the relatively large sizes of these dwarfs, we argue that at least some must have a large dark matter component to prevent their disruption by the cluster potential. We further derive a new method to quantify the dark matter content of cluster dSphs without the use of kinematics, which are impossible to obtain at these distances. We find that mass‐to‐light ratios for dwarfs in the core of the Perseus Cluster are comparable to those found for Local Group dSphs, ranging between M⊙/L⊙ ≈ 1 and 120. This is evidence that dwarf spheroidals reside in dark matter subhalos that protect them from tidal processes in the cores of dense clusters (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Transport of cosmic rays in the nearby starburst galaxy NGC 253
Authors: Heesen V. , Beck R. , Krause M. , Dettmar R.‐J.
Published: November 2009

Radio halos require the coexistence of extra‐planar cosmic rays and magnetic fields. Because cosmic rays are injected and accelerated by processes related to star formation in the disk, they have to be transported from the disk into the halo. A vertical large‐scale magnetic field can significantly enhance this transport. We observed NGC 253 using radio continuum polarimetry with the Effelsberg and VLA telescopes. The radio halo of NGC 253 has a dumbbell shape with the smallest vertical extension near the center. With an estimate for the electron lifetime, we measured the cosmic‐ray bulk speed as 300 ± 30 km s–1 which is constant over the extent of the disk. This shows the presence of a “disk wind” in NGC 253. We propose that the large‐scale magnetic field is the superposition of a disk (r, ϕ) and halo (r, z) component. The disk field is an inward‐pointing spiral with even parity. The conical (even) halo field appears in projection as an X‐shaped structure, as observed in other edge‐on galaxies. Interaction by compression in the walls of the superbubbles may explain the observed alignment between the halo field and the lobes of hot Hα and soft X‐ray emitting gas. The disk wind is a good candidate for the transport of small‐scale helical fields, required for efficient dynamo action, and as a source for the neutral hydrogen observed in the halo (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Morphological properties of isolated galaxies vs. isolation criteria
Authors: Vavilova I.B. , Melnyk O.V. , Elyiv A.A.
Published: November 2009

We studied the morphological properties of isolated galaxies samples in dependence on the isolation parameter and properties of primary catalogs. With this aim we identified the samples of single and isolated galaxies from SDSS DR5 (Single and QIsol) with the 3D Voronoi tessellation method (Elyiv et al. 2009). We found that in comparison with other samples of isolated galaxies, the QIsol sample contains an excess of late‐type galaxies, especially with a low luminosity and BCG/Im/Irr morphology. We also showed that the fractions of early type galaxies in QIsol SDSS DR5 sample and samples 2MIG (Karachentseva et al. 2010) and CIG (Karachentseva et al. 1973; Hernandez‐Toledo et al. 2008) are in a good agreement (16–19 %), but Allam's (Allam et al. 2005) and Prada's (Prada et al. 2003) SDSS DR1 samples show a higher excess of the early type galaxies that can be explained by the selection criteria and morphology definition method. We found a weak relation between isolation parameter and color index for the Single sample that may indicate that even in the low dense environment the morphology density relation is observed. We conclude that morphological properties of the resulting sample of isolated galaxies are highly dependent on the primary catalogue from which the galaxies were selected. Moreover, the selection criterion is also important but plays a secondary role in the resulting morphological content, color indices distribution and other parameters of the isolated galaxy samples. Only four galaxies are common in the 2MIG, QIsol, and CIG samples, namely UGC5184, UGC6121, UGC8495, and UGC9598, that allows to consider them as really most isolated galaxies (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
NGC 1275: Baryonic cycing in the Perseus cluster of galaxies
Authors: Gallagher J.S.
Published: November 2009

NGC 1275, the central galaxy of the Perseus cluster, contains a remarkable cool ISM. This gas is arrayed in a series of filaments extending over 30 kpc with an extension of 70 kpc to the north. These emit substantial cooling line radiation from HII, a hot H2 zone, and CO in a cool molecular region which contains most of the gas mass. This contribution briefly discusses some of the issues raised by the existence of this remarkable ISM system, including its connections to galactic feedback processes (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Early‐type dwarf galaxies in clusters: A mixed bag with various origins?
Authors: Lisker T.
Published: November 2009

The formation ofearly‐type dwarf(dE) galaxies, the most numerous objects in clusters, is believed tobe closely connected to the physical processes that drive galaxy cluster evolution, like galaxy harassment and ram‐pressure stripping. However, the actual significance ofeach mechanism for building the observed cluster dE population is yet unknown. Several distinct dE subclasses were identified, which show significant differences in their shape, stellar content, and distribution within the cluster. Does this diversity imply that dEs originate from various formation channels? Does “cosmological” formation play a role as well? I try to touch on these questions in this brief overview of dEs in galaxy clusters (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)