bluuebunny/crossref_metadata_2025_split huggingface dataset:
Assessment of organochlorine pesticides and metals in ring‐tailed lemurs (Lemur catta) at Beza Mahafaly Special Reserve, Madagascar
Authors: Rainwater Thomas R. , Sauther Michelle L. , Rainwater Katherine A.E. , Mills Rachel E. , Cuozzo Frank P. , Zhang Baohong , McDaniel Les N. , Abel Michael T. , Marsland Eric J. , Weber Martha A. , Youssouf Jacky Ibrahim Antho , Platt Steven G. , Cobb George P. , Anderson Todd A. 
Published: September 2009

AbstractLike most of Madagascar's endemic primates, ring‐tailed lemurs (Lemur catta) face a number of threats to their survival. Although habitat loss is of greatest concern, other anthropogenic factors including environmental contamination may also affect lemur health and survival. In this study, we examined ring‐tailed lemurs from the Beza Mahafaly Special Reserve (BMSR), southern Madagascar for exposure to organochlorine (OC) pesticides and metals and examined differences in contaminant concentrations between sexes and among age groups, troops, and habitats. A total of 14 pesticides and 13 metals was detected in lemur blood (24 individuals) and hair (65 individuals) samples, respectively. p,p′‐DDT, heptachlor, aldrin, heptachlor epoxide, endrin aldehyde, and endrin were among the most prevalent pesticides detected. Surprisingly, the persistent metabolite of p,p′‐DDT, p,p′‐DDE, was not detected. The most commonly detected metals were aluminum, zinc, boron, phosphorus, silicon, and copper, whereas metals considered more hazardous to wildlife (e.g. arsenic, cadmium, lead, selenium, vanadium) were not found above detection limits. Overall, concentrations of OC pesticides and metals were low and similar to those considered to be background concentrations in other studies examining the ecotoxicology of wild mammals. Few inter‐sex, ‐age, ‐troop, and ‐habitat differences in contaminant concentrations were observed, suggesting a uniform distribution of contaminants within the reserve. Several statistically significant relationships between lemur body size and contaminant concentrations were observed, but owing to the lack of supportive data regarding contaminant exposure in wild primates, the biological significance of these findings remains uncertain. Results of this study document exposure of ring‐tailed lemurs at BMSR to multiple OC pesticides and metals and provide essential baseline data for future health and toxicological evaluations of lemurs and other wild primates, especially those in regions with expanding agricultural and mining operations. Am. J. Primatol. 71:998–1010, 2009. © 2009 Wiley‐Liss, Inc.
Pd–Ag membranes for auto‐thermal ethanol reforming
Authors: Tosti Silvano , Borelli Rodolfo , Santucci Alessia , Scuppa Leonardo 
Published: September 2009

AbstractThe auto‐thermal ethanol reforming was carried out at 200 kPa by a two‐step process consisting of a traditional reformer operating at high temperature (700–740 °C) and a Pd–Ag multitube membrane module where the separation of hydrogen took place at 350–380 °C.The membrane module was a bundle of 11 thin‐wall Pd–Ag tubes of wall thickness 50–60 µm, diameter 10 mm, and length 270 mm: permeation tests were performed at 300–395 °C with lumen pressure of 150–200 kPa, and nitrogen sweep flow rates in the shell side ranged from 10 to 30 l min−1 at atmospheric pressure. A hydrogen permeance Pe = 1.317 × 10−2 exp (−3.622 × 103/T(K)) mol m−2 s−1 Pa−0.5 was measured and complete hydrogen selectivity was verified.A water/ethanol mixture of molar ratio 2.50/1.00 was used as feed stream for carrying out ethanol reforming in the traditional fixed‐bed reactor filled with a Ni on alumina catalyst. As a second step, the water gas shift (WGS) membrane reaction was carried out in the multitube membrane reactor: the Pd–Ag alloy of the membrane tubes worked for both catalyzing the reaction and for separating all the hydrogen produced in the reformer and in the membrane reactor itself. The hydrogen separated through the membrane was collected in the shell side of the membrane module: by operating with a water/ethanol feed flow rate of 200 g h−1, up to 1.2 l min−1 of pure hydrogen was produced. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.
Multiple percolation in a carbon‐filled polymer composites via foaming
Authors: Thompson M. R. , Motlagh G. H. , Oxby K. J. , Hrymak A. N. 
Published: September 2009

AbstractThis article describes an investigation into the effects of foaming on the electrical conductivity for a carbon‐filled cyclic olefin copolymer (COC) composite incorporating both chopped carbon fibers (cCF) and carbon black (CB). Foamed and solid samples were injection molded and then analyzed for cell size, fiber length, fiber orientation, and electrical conductivity. Foamed samples exhibited higher electrical conductivity in the through‐plane direction for materials containing only CB or composites containing both filler types, and reduced electrical conductivity in the cCF‐filled composites. The increased electrical property gained by foaming was attributed to multiple percolation with CB aggregates forming more effective conductive clusters and networks in the continuous polymer phase during growth of the gas domains. A mechanism for the phenomenon was proposed based on these experimental observations. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation and characterization of polypropylene homocomposites: Exploiting polymorphism of PP homopolymer
Authors: Karger‐Kocsis J. , Wanjale S. D. , Abraham T. , Bárány T. , Apostolov A. A. 
Published: September 2009

AbstractIn this study, the properties of polypropylene (PP) homocomposites, prepared by film‐stacking followed by hot pressing, were investigated. Alpha‐ and beta‐PP served as matrices, whereas highly oriented PP tapes of the alpha form acted as reinforcement in the homocomposites. Tapes with different draw ratios (DR = 6–12) have been produced and characterized by mechanical and wide‐angle X‐ray scattering measurements. Tapes with a DR = 8 were incorporated in a cross‐ply (CP) manner in the corresponding homocomposite laminates. Specimens were subjected to static (tensile, flexural) and dynamic (instrumented falling weight impact, IFWI) tests. The thermal and thermomechanical properties of the PP tapes and homocomposites were studied by differential scanning calorimetry and dynamic mechanical thermal analysis. The homocomposite morphology was probed by polarized light microscopy, which gave evidence of transcrystalline layer at the interface between tape and matrix. The storage modulus of the CP homocomposites was improved prominently by the tape reinforcement. In static tensile tests, the homocomposites exhibited much higher stiffness and strength when compared with the neat PP specimens. However, this was accompanied with a marked reduction in the ultimate elongation. The IFWI tests showed that both alpha‐ and the beta‐PP failed in macroscopically brittle manner, whereas the corresponding homocomposites failed in semiductile way. The homocomposite laminates prepared with beta‐PP matrix exhibited higher resistance to penetration than those with alpha‐PP. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Room temperature‐curable VARTM epoxy resins: Promising alternative to vinyl ester resins
Authors: Chatterjee Amit , Gillespie John W. 
Published: September 2009

AbstractThe objective of this investigation is to characterize various room temperature (RT)‐curable epoxies for vacuum‐assisted resin transfer molding (VARTM) of large structure manufacturing. Six epoxy candidate resins: X‐40, 780‐33, 780‐35, 8601/8602, 8602, 8603, and two vinyl ester resins (VE), 411‐350 and 411‐510A, are physically and thermochemically characterized. All the resins are cured at RT with extended period of time. The degree of cure for 24‐h RT‐cured samples ranges from 70 to 85% for epoxies and is comparable with the baseline VE systems (75%). After 1 year at RT, the degree of cure increases from 90 to 98%. Most of the epoxies show a single transition in dynamic mechanical analysis and differential scanning calorimetry. However, two heterogeneous transitions are observed for the VE systems. The glass transition temperature increases monotonically with exposure time, except X‐40, that rapidly achieves a plateau and remains constant. The degree of cure for the majority of the systems increases logarithmically with RT curing time with excellent fitting (R2 varies from 0.92 to 1). Consistent with the increase in degree of cure, the storage modulus increases and (tan δ)max decreases with time of exposure. A negative correlation between the curing temperature range and the total heat of reaction is observed among the epoxy systems. However, the VE systems show the reverse trend. RT curing epoxy resin (X‐40) shows promising overall result to VE system and can be a viable alternative to VE for VARTM processing. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of the temperature on the kinetic of natural rubber vulcanization with the sulfur donor agent dipentamethylene thiuram tetrasulphide
Authors: Posadas P. , Fernández‐Torres A. , Valentín J. L. , Rodríguez A. , González L. 
Published: September 2009

AbstractThe effect of the temperature on the kinetics of vulcanization of natural rubber with the sulfur donor agent dipentamethylene thiuram tetrasulphide (DPTT) was investigated. The oscillatory disk rheometer and differential scanning calorimetry under dynamic and isothermal conditions were used. The Coran's model was applied to set the kinetic constants within each distinct step of the vulcanization process using the obtained values of the rheometer curves. During the curing period it was observed that there were two stages. Either the torque increment (ΔS) or the crosslink density arise a maximum value at 130°C. The dynamic and isothermal thermograms showed two overlapped peaks during the curing reaction. These results were in concordance with those obtained by curemeter testing. In addition, the activation energy of the vulcanization process was also calculated by means of both techniques. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Nucleation mechanism of polyhydroxybutyrate and poly(hydroxybutyrate‐co‐hydroxyhexanoate) crystallized by orotic acid as a nucleating agent
Authors: Jacquel Nicolas , Tajima Koichirou , Nakamura Nobuo , Kawachi Hideo , Pan Pengju , Inoue Yoshio 
Published: September 2009

AbstractThe mechanism involved in the crystallization of bacterial polyhydroxybutyrate (PHB) and poly(hydroxybutyrate‐co‐hydroxyhexanoate) P(HB‐co‐HH) induced by orotic acid as a nucleant was investigated by using differential scanning calorimetry (DSC), gel permeation chromatography (GPC) and proton nuclear magnetic resonance spectroscopy (1H‐NMR). GPC measurements both carried on solvent cast and hot pressed samples did not show any significant drop of the molecular weight caused by the addition of the nucleant, indicating that no chemical reaction happened during the nucleation process. This result was confirmed by 1H‐NMR analysis of oligohydroxybutyrate (OHB) treated with an excess amount of orotic acid. The possibility of epitaxial growth of the polymer crystal on the surface of the nucleant crystal was then investigated. It was found that there is an outstanding crystalline lattice matching between the plane (100) of the PHB crystal and the plane (001) of the orotic acid crystal. In comparison, the matching obtained with conventional nucleating agents, such as boron nitride and talc, was worse. Moreover, some regular hydrogen bonds between the polyester and orotic acid could stabilize the physical process. According to these results, the physical mechanism involving the epitaxial matching between orotic acid and PHB appears to be the most probable nucleation mechanism. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Isothermal cold crystallization and melting behaviors of poly(L‐lactic acid)s prepared by melt polycondensation
Authors: Wu Linbo , Hou Hongbin 
Published: September 2009

AbstractThe isothermal cold crystallization and melting behaviors of poly(L‐lactic acid)s (PLLAs, weight average molecular weight, Mw, 6000–80,000) prepared via melt polycondensation were studied with differential scanning calorimeter in this work. It is found that the crystallization rate increased with decreasing Mw, reached a maximum at Mw of ca. 21,000 and then decreased again. The crystallinity of PLLA can be controlled in the range 30–50% by crystallization temperature (Tc) and time to fulfill the requirement of subsequent solid state polycondensation. The melting behavior strongly depends on Tc. The samples crystallized at high Tc melted with a single peak but those crystallized at low Tc melted with double peaks. The higher melting point (TmH) kept almost constant and the lower melting point (TmL) increased clearly with Tc. But the TmL changed in jumps and a triple melting peak appeared at the vicinity of a characteristic crystallization temperature Tb, possibly because of a change of crystal structure. The equilibrium melting temperature of PLLA with Mw of 21,300 was extrapolated to be 222°C with nonlinear Hoffman‐Weeks method. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis, electroluminescence, and photovoltaic cells of new vinylene‐copolymers with 4‐(anthracene‐10‐yl)‐2,6‐diphenylpyridine segments
Authors: Mikroyannidis John A. , Vellis Panagiotis D. , Yang Sheng‐Hsiung , Hsu Chain‐Shu 
Published: September 2009

AbstractThree new soluble vinylene‐copolymers F, C, and P that contain 4‐(anthracene‐10‐yl)‐2,6‐diphenylpyridine as common segment and fluorene, carbazole, or phenylene, respectively, as alternating segment were prepared by Heck coupling. The glass transition temperature was high for F and C (110 and 117°C), whereas was lower than 25°C for P. The polymers were stable up to ∼ 300°C. They emitted blue–green light with maximum located at wavelength of 456–550 nm, which was of the order F < C < P. The photoluminescence quantum efficiency in THF solution was ∼ 30% for F and P and only 5% for C. All three copolymers were used as active layers for polymer light emitting diodes (PLEDs) and organic photovoltaic cells. The double PLEDs with configuration of indium‐tin oxide (ITO)/poly(ethylenedioxythiophene (PEDOT) : poly(styrenesulfonate)(PSS)/Copolymer F, C, or P/TPBI(1,3,5‐tris(2‐N‐phenylbenzimidazolyl)benzene)/Ca/Al were fabricated. Copolymer P emitted green light with maximum brightness of 28 cd/m2 and a current yield of 0.85 cd/A. Organic photovoltaics with the configuration of ITO/PEDOT : PSS/Copolymer and [6,6]‐phenyl‐C61‐butyric acid methyl ester blend (1 : 1) /Ca/Al were also fabricated. Copolymer P showed the highest power conversion efficiency of 0.034%. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Hydrophilic polystyrene/maleic anhydride ultrafine fibrous membranes
Authors: Cécile Corine , Hsieh You‐Lo 
Published: September 2009

AbstractPolystyrene/maleic anhydride (PSMA) was synthesized to reach a viscosity‐average molecular weight of 700 kDa and fabricated into ultrafine fibrous membranes consisting of fibers with an average diameter of 300 nm. These ultrafine PSMA fibers were rendered insoluble in organic solvents by reactions with hydrazine and ethylenediamine (ED). The highly efficient incorporation of diamines into the fibrous membranes was easily achieved by brief immersions in either dilute (0.5 wt %) hydrazine for 1 min or ED ether solution for 2 min. Heating at 150°C for 5 min produced crosslinked PSMA with very little or no solubility in acetone with the retention of the fibrous membrane structure. The ED‐crosslinked membranes were particularly stable to both bases and acids as well as hydrophilic solvents, had a 46° water contact angle, and absorbed 22 times the amount of water as the as‐spun fibrous membrane. This post‐fiber‐formation crosslinking approach was robust, highly efficient, and fast and required very little crosslinking reagent. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of clay dispersion on the synergism between clay and intumescent flame retardants in polystyrene
Authors: Chen Yajun , Fang Zhengping , Yang Chunzhuang , Wang Yu , Guo Zhenghong , Zhang Yan 
Published: September 2009

AbstractDifferent formulations were designed to evaluate the effect of organically modified clay (DK4) on the combustion behavior of polystyrene (PS) containing an intumescent flame retardant, poly(4,4‐diaminodiphenyl methane spirocyclic pentaerythritol bisphosphonate) (PDSPB). The results of transmission electron microscopy reveal that DK4 selectively dispersed in the PDSPB phase. An investigation of thermogravimetric analysis revealed that the thermal stability of PS resin showed no obvious change with the addition of PDSPB and DK4, but the residue increased. From the results of cone calorimetry, we observed that there were two steps during combustion. The dispersion of DK4 played an important role in improving the thermal stability and the flammability of the PS/PDSPB/DK4 nanocomposites. In the first step, DK4 was restricted in the PDSPB phase; there was no synergistic effect. A synergistic effect occurred in the second step when clay had a homogeneous distribution, in which the peak heat release rates were reduced by about 40 and 61% compared to the pure PS. A model of combustion behavior was developed according to these results. The synergistic mechanism was caused by the formation of the silicoaluminophosphate (SAPO) structure formed by reactions between PDSPB and DK4. Field emission scanning electron microscopy characterization showed that such an SAPO structure led to a ceramic‐like residue after burning. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
A study of antimicrobial property of textile fabric treated with modified dendrimers
Authors: Ghosh Subhas , Yadav Sangeeta , Vasanthan Nadarajah , Sekosan Gabriela 
Published: September 2009

AbstractDendrimers have been used as a vehicle to develop the antimicrobial properties of textile fabrics. We have taken advantage of the large number of functional groups present in the regular and highly branched three‐dimensional architecture of dendrimers. In this study, the poly(amidoamine) (PAMAM) G‐3 dendrimer was modified to provide antimicrobial properties. Following a procedure similar to what is suggested in the literature, PAMAM (G3) with primary amine end groups was converted into ammonium functionalities. The modification was then confirmed by FTIR and 13C‐NMR analysis. Dendrimers have unique properties owing to their globular shape and tunable cavities, this allows them to form complexes with a variety of ions and compounds; and also act as a template to fabricate metal nanoparticles. AgNO3–PAMAM (G3) complex as well as a MesoSilver–PAMAM (G3) complex were formed and these modified dendrimers were characterized by a UV–Visible spectrophotometer to study the complex formation. Modified dendrimers were applied to the Cotton/Nylon blend fabric. SEM and EDX analysis were performed to study the dispersion of silver nanoparticles onto the fabric. An antimicrobial test of the treated‐fabric against Staphylococcus aureus exhibited significant biocidal activities for each type of modified‐dendrimer. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
The Cage and Metal Effect: Spectroscopy and Electrochemical Survey of a Series of Sm‐Containing High Metallofullerenes
Authors: Liu Jia , Shi Zujin , Gu Zhennan 
Published: September 2009

AbstractA series of Sm‐containing high metallofullerenes, namely, Sm@C82 (I, II, III, IV), Sm@C84 (I, II, III), Sm@C86, Sm@C88 (I, II, III), Sm@C90 (I, II, III), Sm@C92 (I, II), Sm@C94 (I, II, III), and Sm@C96, is successfully synthesized and characterized by UV/Vis/NIR absorption spectroscopy, and cyclic and differential pulse voltammetry. Sm‐containing high metallofullerenes have a relatively larger number of isomers compared with other divalent ones. The highest boiling point of Sm among Group II metals may be responsible for this phenomenon. Comparing the spectroscopic and electrochemical behaviors of Sm‐containing metallofullerenes with those of other divalent ones, it is seen that when the size of the carbon cage enlarges, different structures form stable molecules with different metals. Furthermore, there are also some important differences in the electrochemistry properties. The cage effect on the electronic structures of high metallofullerenes is also estimated from the differences in reduction potentials between metallofullerenes and their corresponding fullerenes. It is believed that the influence of transferred electrons from the metal to the carbon cage becomes much weaker for high fullerenes. The redox property of high metallofullerene is more dependent on the carbon‐cage structure than the effect of electron transfer.
Synthesis and luminescence properties of lanthanide complexes with a new tripodal ligands featuring salicylamide arms
Authors: Song Xue‐Qin , Dong Wen‐Kui , Zhang Yu‐Jie , Liu Wei‐Sheng 
Published: September 2009

AbstractA series of luminescent lanthanide complexes with a new tripodal ligand featuring salicylamide arms, 2,2′,2″‐nitrilotris(2‐furfurylaminoformylphenoxy)triethylamine (L), were synthesized and characterized by elemental analysis, IR and molar conductivity measurements. Photophysical properties of the complexes were studied by means of UV–vis absorption and steady‐state luminescence spectroscopy. Excited‐state luminescence lifetimes and quantum yield of the complexes were determined. Luminescence studies demonstrated that the tripodal ligand featuring salicylamide arms exhibits a good antennae effect with respect to the Tb(III) and Dy(III) ion due to efficient intersystem crossing and ligand to metal energy transfer. From a more general perspective, this work offers interesting perspectives for the development of efficient luminescent stains and enlarges the arsenal for developing novel luminescent lanthanide complexes of salicylamide derivatives. Copyright © 2009 John Wiley & Sons, Ltd.
G‐rich sequence‐functionalized polystyrene microsphere‐based instantaneous derivatization for the chemiluminescent amplified detection of DNA
Authors: Xin Liang , Cao Zhijuan , Lau Choiwan , Kai Masaaki , Lu Jianzhong 
Published: September 2009

AbstractHerein, we develop a novel chemiluminescence (CL) approach with high sensitivity and excellent selectivity, by taking advantage of magnetic beads as preconcentration carriers and polystyrene microspheres as an amplification platform. Briefly, a ‘sandwich‐type’ detection strategy is employed in our design, which involves capture probe DNA immobilized on the surface of carboxyl‐terminated magnetic beads and multiple biotinylated reporter DNA self‐assembled on the surface of streptavidin‐modified polystyrene microspheres. The reporter DNA includes a guanine nucleobase‐rich (G‐rich) sequence domain for the generation of light and an additional tethered nucleic acid domain complementary with the target DNA. The CL signal is obtained via a novel instantaneous derivatization reaction between a specific CL reagent and the guanine nucleo­bases rich in the target and reporter DNA. As a result, we demonstrate that this DNA assay is reproducible, stable, easy to use, and can sensitively detect femtomolar target DNA related to anthrax lethal factors with excellent differentiation ability for single‐base mismatched sequences. Overall, this new CL protocol couples the high sensitivity of CL analysis with effective magnetic separation for discriminating against unwanted constituents such as mismatched sequences, and hence, offers great promise for DNA hybridization analysis. Copyright © 2009 John Wiley & Sons, Ltd.