bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structural and mechanical properties of polystyrene nanocomposites with 1D titanate nanostructures prepared by an extrusion process
Authors: Umek Polona , Huskić Miroslav , Škapin Andrijana Sever , Florjančič Urška , Zupančič Barbara , Emri Igor , Arčon Denis 
Published: September 2008

AbstractPolystyrene (PS) nanocomposites with titanate nanotubes and titanate nanoribbons were prepared by an extrusion process at 180°C. Nanocomposites with 1 wt% of nanofillers and pure PS that had also been exposed to the extrusion process were comparatively examined with scanning electron microscopy (SEM), electron dispersive X‐ray spectrometry (EDS) mapping, solid state proton nuclear magnetic resonance measurements (1H NMR), tensile tests, and shear creep measurements. SEM images and EDS mapping analysis show that titanate nanoribbons homogeneously distribute at a micrometer length‐scale in the PS matrix during the extrusion process. This is not the case for titanate nanotubes, which show a stronger tendency to form clusters. Solid state 1H NMR studies, however, proved that the nanocomposites are inhomogeneous at a nanometric scale where structural components with highly mobile PS molecules coexist with domains of rigid PS molecules. Differences in the 1H spin‐lattice relaxation at and above the glass transition temperature Tg = 373 K suggest that nanofillers affect the thermodynamic properties of nanocomposite domains. Only a slight increase in mechanical tensile properties was observed in the case of the nanocomposite containing 1 wt% of titanate nanoribbons (TiNRs) probably reflecting a weak interaction between the polymer matrix and the nanofiller. Nevertheless, our results prove that the use of functionalized TiNRs may, in combination with the extrusion process, represent a very promising starting point for the preparation of TiNR nanocomposites at the industrial level. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Fabrication and properties of clay‐supported carbon nanotube/poly (vinyl alcohol) nanocomposites
Authors: Zhao Yong‐Qing , Lau Kin‐Tak , Wang Zhe , Wang Zhi‐Cai , Cheung Hoi‐Yan , Yang Zhi , Li Hu‐Lin 
Published: September 2008

AbstractClay‐supported carbon nanotubes (Cs‐CNTs) were used as novel nanofillers to improve the thermal and mechanical properties of a polymer. Cs‐CNT/poly (vinyl alcohol) (PVA) nanocomposite films were successfully fabricated, and their relative properties were investigated by using differential scanning calorimetry, thermogravimetric analysis, and dynamic mechanical analysis. Experimental results showed that the thermal stability and dynamic mechanical properties of PVA were remarkably enhanced by incorporating the Cs‐CNTs into PVA matrix. The largest Tg difference of 14°C was obtained between pure PVA and PVA nanocomposite with 7 wt% Cs‐CNTs. Moreover, the storage modulus of PVA was significantly improved by 133% at 50°C, when 7 wt% Cs‐CNTs was added to PVA matrix. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Optical, rheological, and thermal properties of hollow glass bead filled isotactic polypropylene
Authors: Zhu Lin , Xu Xinhua , Song Na , Tang Xiangyang 
Published: September 2008

AbstractHollow glass beads (HGB) were mixed into isotactic polypropylene (iPP) by an internal mixer and the effect of HGB concentration on optical, rheological, and thermal properties of iPP/HGB composites was studied. The dispersion of treated and nontreated HGB in the iPP matrix and the crystal habit of iPP in the composites were examined by phase contrast microscopy. Dynamic rheological measurements were carried out in the melt state in the oscillatory shear mode. The data were analyzed to yield the variations of rheological properties of the composites when the HGB were added. The influence of HGB concentration on the thermal properties including the crystallization and melting behaviors of the composites was studied by means of differential scanning calorimeter and wide angle X‐ray diffraction. It was found that the addition of HGB had effect on the crystallization and melting behaviors of the composites, including that HGB had a weak nucleating effect in the matrix and promoting the formation of β‐crystals of iPP. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Calorimetric studies on an anhydride‐cured epoxy resin from diglycidyl ether of bisphenol‐A and diglycidyl ether of poly(propylene glycol). I. Onset of diffusion control during isothermal polymerization
Authors: Xu Jianjun , Holst Marco , Wenzel Mirko , Alig Ingo 
Published: September 2008

AbstractCalorimetric studies on a series of anhydride‐cured epoxy resins, in which the epoxy oligomer is a mixture of diglycidyl ether of bisphenol‐A (DGEBA) and diglycidyl ether of poly(propylene glycol) (DGEPPG) in different mole ratios, were carried out. DGEPPG is a flexible epoxy oligomer that was used to tune glass transition temperature for the fully reacted epoxy resin. Conversion versus time curves for the systems with different DGEBA/DGEPPG mole ratios (not including the neat DGEPPG system) were found to overlap with each other in mass‐controlled reaction regime, indicating similar reactivities of epoxy groups in both epoxy oligomers. Onset of diffusion‐controlled reaction regime for different systems was estimated by fitting the conversion versus time data using a phenomenological kinetic equation, as well as from direct comparison of the conversion versus time curves. For the systems (i.e., 0, 10, and 30% DGEPPG) that vitrify during reaction, the crossover from mass‐controlled to diffusion‐controlled reaction occurs close to the onset of the vitrification, where Tg is about 25–30 K below the reaction temperature. For the system (i.e., 50% DGEPPG system) that does not vitrify during the reaction, such crossover still occurs when the Tg of the mixture reaches a value about 25 K below the reaction temperature. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2155–2165, 2008
The effect of ions irradiation on the thermal properties of poly(ether ether ketone)
Authors: Al Lafi Abdul G. , Hay James N. , Parker David J. 
Published: September 2008

AbstractThe effect of irradiating amorphous poly (ether ether ketone), PEEK, with ions, 11 MeV proton (H+), and 25.6 MeV helium (He2+), has been investigated focusing on the changes in thermal properties. The extent of chain scission and crosslinking was evaluated using the Charlesby‐Pinner equation. Crosslinking increased the glass transition temperature (Tg) in line with the DiBenedetto equation from which the crosslinking constant for each ion was calculated. The effect of irradiation on the thermal degradation kinetics was studied in an argon atmosphere at a constant heating rate by mean of the Chang and the second Kissinger methods. Irradiation significantly reduced the thermal stability of the polymer and its service lifetime. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2212–2221, 2008
Poly(L‐lactide)/layered double hydroxides nanocomposites: Preparation and crystallization behavior
Authors: Pan Pengju , Zhu Bo , Dong Tungalag , Inoue Yoshio 
Published: September 2008

AbstractNovel nanocomposites from poly(L‐lactide) (PLLA) and an organically modified layered double hydroxide (LDH) were prepared using the melt‐mixing technique. The structure and crystallization behavior of these nanocomposites were investigated by means of wide‐angle X‐ray diffraction (WAXD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and polarized optical microscopy (POM). WAXD results indicate that the layer distance of dodecyl sulfate‐modified LDH (LDH‐DS) is increased in the PLLA/LDH composites, compared with the organically modified LDH. TEM analysis suggests that the most LDH‐DS layers disperse homogenously in the PLLA matrix in the nanometer scale with the intercalated or exfoliated structures. It was found that the incorporation of LDH‐DS has little or no discernable effect on the crystalline structure as well as the melting behavior of PLLA. However, the crystallization rate of PLLA increases with the addition of LDH‐DS. With the incorporation of 2.5 wt % LDH‐DS, the PLLA crystallization can be finished during the cooling process at 5 °C/min. With the addition of 5 wt % LDH‐DS, the half‐times of isothermal melt‐crystallization of PLLA at 100 and 120 °C reduce to 44.4% and 57.0% of those of the neat PLLA, respectively. POM observation shows that the nucleation density increases and the spherulite size of PLLA reduces distinctly with the presence of LDH‐DS. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2222–2233, 2008
Study of clay nanocomposites of the biodegradable polyhexamethylene succinate. Application of isoconversional analysis to nonisothermal crystallization
Authors: Gestí S. , Zanetti M. , Lazzari M. , Franco L. , Puiggalí J. 
Published: September 2008

AbstractNanocomposites of organomodified montmorillonites and the biodegradable polyester derived from hexanediol and succinic acid were prepared by the solution‐casting method using chloroform as solvent. Samples were studied by means of X‐ray diffraction and transmission electron microscopy. Intercalated structures differentiated by the stacking mode between silicate layers were observed. The highest variability in interlayer spacing was found when C30B organoclay was added. In this case, hydroxyl groups of the modifier could interact with polar carbonyl groups of the polyester. Thermal stability and crystallization behavior under both isothermal and nonisothermal conditions were evaluated. The overall crystallization rate of the intercalated nanocomposites was higher than that of the neat polyester due to a significant increase in their nucleation density, which compensated for their lower crystal growth rate. Isoconversional analysis was used to determine effective activation energies and to estimate nucleation and transport energy parameters from nonisothermal hot crystallization experiments. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2234–2248, 2008
Self‐assembly of polymer‐coated ferromagnetic nanoparticles into mesoscopic polymer chains
Authors: Benkoski Jason J. , Bowles Steven E. , Jones Ronald L. , Douglas Jack F. , Pyun Jeffrey , Karim Alamgir 
Published: September 2008

AbstractThe self‐assembly of dispersed polymer‐coated ferromagnetic nanoparticles into micron‐sized one‐dimensional mesostructures at a liquid–liquid interface was reported. When polystyrene‐coated Co nanoparticles (19 nm) are driven to an oil/water interface under zero‐field conditions, long (≈ 5 μm) chain‐like assemblies spontaneously form because of dipolar associations between the ferromagnetic nanoparticles. Direct imaging of the magnetic assembly process was achieved using a recently developed platform consisting of a biphasic oil/water system in which the oil phase was flash‐cured within 1 s upon ultraviolet light exposure. The nanoparticle assemblies embedded in the crosslinked phase were then imaged using atomic force microscopy. The effects of time, temperature, and colloid concentration on the self‐assembly process of dipolar nanoparticles were then investigated. Variation of either assembly time t or temperature T was found to be an interchangeable effect in the 1D organization process. Because of the dependence of chain length on the assembly conditions, we observed striking similarities between 1D nanoparticle self‐assembly and polymerization of small molecule monomers. This is the first in‐depth study of the parameters affecting the self‐assembly of dispersed, dipolar nanoparticles into extended mesostructures in the absence of a magnetic field. © 2008 Wiley Periodicals, Inc.* J Polym Sci Part B: Polym Phys 46: 2267–2277, 2008
Tracking humoral responses using self assembling protein microarrays
Authors: Ramachandran Niroshan , Anderson Karen S. , Raphael Jacob V. , Hainsworth Eugenie , Sibani Sahar , Montor Wagner R. , Pacek Marcin , Wong Jessica , Eljanne Mariam , Sanda Martin G. , Hu Yanhui , Logvinenko Tanya , LaBaer Joshua 
Published: September 2008

AbstractThe humoral immune response is a highly specific and adaptive sensor for changes in the body's protein milieu, which responds to novel structures of both foreign and self antigens. Although Igs represent a major component of human serum and are vital to survival, little is known about the response specificity and determinants that govern the human immunome. Historically, antigen‐specific humoral immunity has been investigated using individually produced and purified target proteins, a labor‐intensive process that has limited the number of antigens that have been studied. Here, we present the development of methods for applying self‐assembling protein microarrays and a related method for producing 96‐well formatted macroarrays for monitoring the humoral response at the proteome scale. Using plasmids encoding full‐length cDNAs for over 850 human proteins and 1700 pathogen proteins, we demonstrate that these microarrays are highly sensitive, specific, reproducible, and can simultaneously measure immunity to thousands of proteins without a priori protein purification. Using this approach, we demonstrate the detection of humoral immunity to known and novel self‐antigens, cancer antigens, autoimmune antigens, as well as pathogen‐derived antigens. This represents a powerful and versatile tool for monitoring the immunome in health and disease.
Photolysis of the herbicide sulcotrione: formation of a major photoproduct and its toxicity evaluation
Authors: Halle Alexandra ter , Wiszniowski Jaroslaw , Hitmi Adnane , Ledoigt Gérand , Bonnemoy Frédérique , Bonnet Jean‐Louis , Bohatier Jacques , Richard Claire 
Published: September 2008

AbstractBACKGROUND: Sulcotrione is a selective herbicide marketed for use in maize since 1993, but its environmental fate is not yet fully elucidated. A major metabolite resulting from cleavage between the two ring moieties, leading to 2‐chloro‐4‐mesylbenzoic acid (CMBA), has been identified; it presents a rather low toxicity. In photochemical studies this compound has also been claimed to be formed in high proportions. The present authors recently found that, under irradiation, sulcotrione mainly yields a cyclization product (CP). Thus, Sulcotrione photochemistry is still a matter of debate. The aim of the present work was to give an unequivocal answer to this issue. The potential toxicity of CP, CMBA and sulcotrione towards three organisms considered as representative of aquatic ecosystems was also evaluated.RESULTS: The main transformation product of sulcotrione is the cyclization product (CP), and CMBA is formed in smaller amounts. For the toxicological approach, the tested organisms were a bacterium, Vibrio fischeri (Bejerinck) Lehmann & Neumann, an alga, Pseudokirchneriella subcapitata (Korshikov) Hindak, and a protozoan, Tetrahymena pyriformis (Ehrenberg) Lwoff. Sulcotrione is more harmful towards the alga, but CP is more toxic to the bacterium and the protozoan. It must be noted that the measured toxicities are nonetheless rather low.CONCLUSION: On irradiation, sulcotrione mainly gives the photocyclization product, which presents a higher toxicity than sulcotrione and CMBA. This cyclization product should thus be considered in sulcotrione environmental risk assessment. Copyright © 2008 Society of Chemical Industry
Differential toxicity of Bacillus thuringiensis strains and their crystal toxins against high‐altitude Himalayan populations of diamondback moth, Plutella xylostella L.
Authors: Mohan Muthugounder , Sushil Satya N , Selvakumar Govindan , Bhatt Jagadish C , Gujar Govind T , Gupta Hari S 
Published: September 2008

AbstractBACKGROUND: Diamondback moth, Plutella xylostella (L.), is a major insect pest of crucifers in the biodiversity‐rich north‐western Indian Himalayan hills. The present investigation was aimed at determining the susceptibility pattern of P. xylostella populations collected from different locations of this region to autochthonous and standard Bacillus thuringiensis strains.RESULTS: Among the reference as well as indigenous B. thuringiensis strains tested, sub spp. kurstaki HD‐1, kurstaki HD‐73, galleriae HD‐8, local galleriae/colmeri strain BtOa1 and some of their Cry1 class toxins were found to be highly toxic. Surprisingly, the sub sp. tolworthi HD‐125, local tolworthi strain BtHa1 and Cry9 class toxins were found to be non‐toxic. Midgut homogenate from fourth‐instar larvae was found to activate 130 kDa protoxin from the local tolworthi strain BtHa1 into 68 kDa toxin, but failed to exert any larval mortality, probably owing to lack of receptor binding.CONCLUSION: The present study provides valuable baseline susceptibility data for the deployment of B. thuringiensis‐based control methods, as well as for future monitoring of development of resistance in P. xylostella to B. thuringiensis in this ecologically sensitive region. Copyright © 2008 Society of Chemical Industry
Molecular Docking and 3‐D QSAR Studies of Substituted 2,2‐Bisaryl‐Bicycloheptanes as Human 5‐Lipoxygenase‐Activating Protein (FLAP) Inhibitors
Authors: Ma Xiang , Zhou Lu , Zuo Zhi‐Li , Liu Jian , Yang Min , Wang Rong‐Wei 
Published: September 2008

AbstractLeukotrienes have been shown to be involved in a variety of diseases such as cardiovascular diseases, cancer, asthma, ulcerative colitis, and rhinitis. 5‐Lipoxygenase‐Activating Protein (FLAP) was found to be a key enzyme of leukotriene synthesis. Comparative Molecular Field Analysis (CoMFA) and molecular docking studies were carried out on a series of substituted 2,2‐bisaryl‐bicycloheptanes FLAP inhibitors. The docking results provided a reliable conformational alignment scheme for 3‐D QSAR model. Based on the docking conformations, highly predictive CoMFA model was performed with a leave‐one‐out cross‐validated q2 of 0.651. The noncross‐validated analysis with four optimum components revealed a conventional r2 value of 0.972, F=175.674, and an estimated standard error of 0.169. The predictive ability of this model was validated by the testing set with a conventional r2 value of 0.920. The analyses may be used to design more potent FLAP inhibitors and predict their activities prior to synthesis.
The charge capacitance of the chemical bond: Application to bonds containing metals
Authors: Holt Asbjørn , Karlström Gunnar , Roos Björn O. 
Published: September 2008

AbstractThe charge capacitance of metal containing complexes are studied. For molecules with multiple bonding between the metal atoms it is found that the charge capacitance is correlated to the maximum bond order, natural bond order, and to some extent the effective bond order. Furthermore the charge capacitance of some methylidene metal dihydride complexes are studied. These molecules have agostic interactions of varying strength, and it is concluded that this strength is very well reflected in the charge capacitances of the systems. In accordance with the definition of agostic interactions it is therefor concluded that the charge capacitance holds information about the strength of covalent interactions. The effect therefore on the agostic interactions upon substitution of one of the hydrogen atoms with fluorine in the methylidene metal complexes is studied, and found to reduce the agostic interactions. It is also demonstrated that there is an agostic interaction in an ArCrCrAr complex. The distance dependence of the charge capacitance is also discussed. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Towards a new index for environmental sustainability based on a DALY weighting approach
Authors: Blanc Isabelle , Friot Damien , Margni Manuele , Jolliet Olivier 
Published: September 2008

AbstractComposite indicators are synthetic indices that are used to rank country performances in specific policy areas. Many do, however, suffer from methodological difficulties. Specific difficulties linked to indices for environmental sustainability are analyzed through the illustration of several sets. The most critical issues are linked with a poor analytical framework and a lack of common unit for the aggregation. Some measure directly the state of the environment while other use proxies such as pressure or response indicators or even a mix of these. A new composite index for environmental sustainability was developed in the EU project EPSILON, which aimed at assessing European regional sustainability for policy decision making related to the improvement of regional sustainability. Indicators are expressed according to a coherent framework issuing from the ‘driving force–pressure–state–impact–response’ approach with an innovative weighting scheme derived from human health impact assessment based on disability adjusted life years (DALYs). Results are compared with a more conventional aggregation technique based on an equal weighting coupled to various normalization techniques. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment.
Operationalization and contextualization of sustainability at the local level
Authors: Hartmuth Gerhard , Huber Katja , Rink Dieter 
Published: September 2008

AbstractDue to its fuzziness, the model of sustainable development has to be particularized and contextualized before it can be used as a yardstick. A local indicator system for two German cities has been developed to meet these requirements using a new conceptualization of sustainability. Initially, local problem areas were identified in a bottom‐up approach by local authority personnel. These problem areas were contrasted with a set of sustainability rules, which had been systematically derived from a basic sustainability norm that gives minimum requirements for sustainable development. Indicators were specified at the interface between local problem areas and sustainability rules. The indicators are expected to provide information on whether the city is over time becoming closer to or farther removed from the respective sustainability goals in its problem areas. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment.
Diagnosis and Management of Male Breast Cancer
Authors: Lanitis Sophocles , Rice Alexandra J. , Vaughan Alexander , Cathcart Paul , Filippakis George , Mufti Ragheed Al , Hadjiminas Dimitri J. 
Published: September 2008

AbstractBackgroundMale breast cancer (MBC) is rare with an incidence of 1% of all breast cancers. The evidence about the treatment is derived from the data on the management of the female breast cancer because conduction of randomized, controlled trials is impossible due to the rarity of the disease. In this study, we review the special features, overall management, diagnosis, and treatment of patients with MBC managed under our care with a brief review of the current literature.MethodsDuring the period 1998 to 2006, we managed 1103 new patients with breast cancer in St Mary’s Hospital. Among these, 14 patients were men. We retrospectively reviewed the case notes, histology, and follow‐up notes of all the newly diagnosed patients with MBC.ResultsIn this series, 28.6% had only in situ disease. Moreover, in 78.6% there was an in situ component present. One patient was found to have a cancer on the microdochectomy specimen after an operation for single duct nipple discharge, and in a second patient the cancer was found in the gynecomastia operation specimen. All ten invasive tumors were estrogen receptor positive (ER +ve), whereas eight were progesterone receptor positive (PgR +ve). With a median follow‐up of 35 months, there was one locoregional recurrence and one disease‐associated death.ConclusionsIn situ cancer may not be as rare as previously reported among patients with MBC. Increased patient awareness and early assessment by a specialist is a key to early diagnosis and improved outcomes.