bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermally stable red electroluminescent hybrid polymers derived from functionalized silsesquioxane and 4,7‐bis(3‐ethylhexyl‐2‐thienyl)‐2,1,3‐benzothiadiazole
Authors: Xiao Yang , Lu Xuehong , Tan Li‐Wei , Ong K.S. , He Chaobin 
Published: September 2009

AbstractHyperbranched organic–inorganic hybrid conjugated polymers P1 and P2 were prepared via FeCl3‐oxiditive polymerization of 4,7‐bis(3‐ethylhexyl‐2‐thienyl)‐2,1,3‐benzothiadiazole (A) and octa(3‐ethylhexyl‐2‐thienyl‐phenyl)polyhedral oligomeric silsesquioxane (POSS) (B) at different POSS concentrations. Compared to linear polymer PM derived from A, P1, and P2 exhibit much higher PL quantum efficiency (ϕPL‐f) in condensed state with improved thermal stability. ϕPL‐f of P1 and P2 increased by 80% and 400%, and the thermal degradation temperatures of P1 and P2 are increased by 35 °C and 46 °C, respectively. Light‐emitting diodes were fabricated using P1, P2, and PM. While the electroluminescent spectra of both P1 and PM show λmax at 660 nm, P1 exhibits a much narrower EL spectrum and higher electroluminescence (∼500%) compared with PM at a same voltage and film thickness. The maximum current efficiency of P1 is more than seven times of that of PM. The turn‐on voltages of the LEDs are in the order of P2 > PM > P1. LED prepared by blending P1 with MEH‐PPV shows a maximum luminescence of 2.6 × 103 cd/m2 and a current efficiency of 1.40 cd/A, which are more than twice (1.1 × 103 cd/m2) and five times (0.27 cd/A) of LED of PM/MEH‐PPV blend, respectively. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5661–5670, 2009
Polyethersulfone‐epoxy terminated materials as thermosetting resins for microelectronic devices
Authors: Scamporrino Emilio , Mineo Placido , Scamporrino Andrea , Dattilo Sandro , Vitalini Daniele , Alicata Rossana 
Published: September 2009

AbstractA totally aromatic polyether/sulfone resin (PES‐E) was synthesized and tested as an insulating glue in the construction of a Chip‐on‐Chip (CoC) device. PES‐E, essentially constituted of open‐chain macromolecules of low molecular mass (Mnof about 3000 Da) with hydroxy and/or epoxy end‐groups, has a glass transition temperature of about 150 °C and is subject to crosslinking at temperatures higher than 320 °C. A CoC device was assembled using a five‐step process by interposing a layer of PES‐E between two chips. After curing, SEM cross section images showed a homogeneous crosslinked resin layer well stuck (flick and shear tests) to both chips. The chemical structure of the chains and the hydroxy/epoxy end‐groups ratio were optimized to obtain a crosslinked material with good adhesion and sufficient flexibility to avoid cracking during assembly and use. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5682–5689, 2009
The effect of ligand on the rate of propagation of Cu(0)‐wire catalyzed SET‐LRP of MA in DMSO at 25 °C
Authors: Nguyen Nga H. , Jiang Xuan , Fleischmann Sven , Rosen Brad M. , Percec Virgil 
Published: September 2009

AbstractThe effect of initial ligand concentration on the apparent rate constant of propagation of single‐electron transfer living radical polymerization (SET‐LRP) of MA in DMSO at 25 °C was examined using various lengths of Cu(0) wire as catalyst. It was determined that unlike other parameters such as initiator concentration, solvent concentration, and deactivator concentration, no simple external rate‐order for the ligand concentration could be determined. Rather, the response of the rate of SET‐LRP to initial ligand concentration is complex and is likely determined by a competition of ligand‐dependent extent of disproportionation as well as the role of ligand concentration in the surface mediated activation process. Results suggest that a minimum concentration of ligand is needed to achieve both acceptable reaction rate and reaction control, and therefore, ligand concentration must be considered in designing experimental conditions for SET‐LRP. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5629–5638, 2009
A thermodynamic analysis of specific interactions in blends of poly(styrene‐co‐N,N‐dimethylacrylamide) and poly(styrene‐co‐acrylic acid). Screening and self‐association effects
Authors: Hadj Hamou Assia Siham , Elmiloudi Khaled , Djadoun Said 
Published: September 2009

AbstractIn a first step of this contribution, the observed glass transition temperature‐composition behavior of miscible blends of poly(styrene‐co‐N,N‐dimethylacrylamide) (SAD17) containing 17 mol % of N,N‐dimethylacrylamide and poly(styrene‐co‐acrylic acid) (SAA18, SAA27, and SAA32) containing increasing acrylic acid content, are analyzed according to theoretical approaches. Both Kwei and Brostow equations describe well the experimental data though better fits were obtained with the Brostow's approach. The specific interactions involved in these systems are a combination of intra and interassociation hydrogen bonding. The positive deviation from the linear mixing rule of Tg‐composition observed within the SAA18+SAD17 blend system, indicates that interassociation interactions are prevailing. More pronounced intra‐association interactions within the SAA32+SAD17 blend system led to a large negative deviation while a fine balance is established between these two types of interactions within the SAA27+SAD17 blend. A thermodynamic analysis was carried out according to the Painter‐Coleman association model. The miscibility and phase behavior of SAD17+SAA18 and SAD17+SAA27 blends are well predicted. However, this model predicts a partial miscibility of SAD17+SAA32 system. Finally, the fitting parameter free method developed by Coleman to predict the Tg‐composition behavior is applied. This method predicts fairly well the evolution trend of experimental Tgs of the SAA18+SAD17 and SAA27+SAD17 blend systems. However, the compositional dependence of SAA32+SAD17 blend Tg was not predictable by this method. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47:2074–2082, 2009
Tuning block copolymer phase behavior with a selectively associating homopolymer additive
Authors: Bosse August W. , Tirumala Vijay R. , Lin Eric K. 
Published: September 2009

AbstractWe use polymer random phase approximation (RPA) theory to calculate the microphase separation transition (MST) spinodal for an AB + C diblock copolymer–homopolymer blend where the C homopolymers are strongly attracted to the A segment of the copolymers. Our calculations indicate that one can shift the MST spinodal value of the A − B segmental interaction parameter (χABN)S to significantly lower values [i.e., (χABN)S < 10.5] upon the addition of a selectively attractive C homopolymer. For a sufficiently attractive C homopolymer, (χABN)S can be pushed to negative values, indicating microphase separation in what would appear to be a completely miscible diblock copolymer. Furthermore, we show that microphase separation can occur in diblock copolymer–homopolymer blends where the segmental interactions between all polymer constituents are attractive. By tuning the value of (χABN)S with a homopolymer additive, one is therefore able to tune the effective copolymer segregation strength and thus dramatically affect the blend phase behavior. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2083–2090, 2009
Microphase separation in block‐random copolymers of styrene, 4‐acetoxystyrene, and 4‐hydroxystyrene
Authors: Quinn Jeffrey D. , Register Richard A. 
Published: September 2009

Abstract“Block‐random” copolymers—where one or more blocks are themselves random copolymers—offer a flexible modification to the usual block copolymer architecture. For example, in a poly(A)‐poly(A‐ran‐B) diblock consisting of monomer units A and B, the interblock segregation strength can be continuously tuned through the B content of the random block, allowing the design of block copolymers with accessible order‐disorder transitions at arbitrarily high molecular weights. Moreover, the development of controlled radical polymerizations has greatly expanded the palette of accessible monomer units A and B, including units with strongly interacting functional groups. We synthesize a range of copolymers consisting of styrene (S) and acetoxystyrene (AS) units, including copolymers where one block is P(S‐ran‐AS), through nitroxide‐mediated radical polymerization. At sufficiently high molecular weights, near‐symmetric PS‐PAS diblocks show well‐ordered lamellar morphologies, while dilution of the repulsive S‐AS interactions in PS‐P(S‐ran‐AS) diblocks yields a phase‐mixed morphology. Cleavage of a sufficient fraction of the AS units in a phase‐mixed PS‐P(S‐ran‐AS) diblock to hydrogen‐bonding hydroxystyrene (HS) units yields, in turn, a microphase‐separated melt. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47:2106–2113, 2009.
Counterion mixing effects on the conformational transitions of polyelectrolytes. II. Counterion binding as measured by NMR spectroscopy of alkali metal poly(acrylate)s
Authors: Wakagawa Masaki , Hayashi Mariko , Kuroki Shigeki , Satoh Mitsuru 
Published: September 2009

AbstractBound states of counterions during the coil‐globule transition of poly(acrylic acid) in water/organic solvent mixtures were investigated by NMR spectroscopy of alkali metal cations (Li+, Na+, Cs+). Accompanying the transition, the line widths of the respective NMR peaks significantly increased with increasing the organic solvent composition in the medium. Although this line width broadening suggests that some specific counterion binding with desolvation is involved with the coil‐globule transition, the most marked broadening was observed in higher organic solvent compositions than those of the coil‐globule transition region detected by the viscometry. Namely, the specific counterion binding with desolvation proceeds even after the polymer chain collapsed. This means in turn that such a strong counterion binding is not a prerequisite for the coil‐globule transition, at least at the stage of the onset. For the Li+/Cs+ mixed counterion system in 60 vol % DMSO, where our previous conductivity data suggested that the specific counterion binding occurred only for Cs+ during the coil‐globule transition induced on mixing with Li+, a significant increase in the line width was also observed only for Cs+. The coincidence between the conductivity and the NMR results for the Li+/Cs+ mixed counterion system strongly supports a working hypothesis, “size‐fitting effect,” that has been proposed to determine the counterion specificity observed for the conformational transitions of polyelectrolytes. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2132–2139, 2009
‘Why I feel bad’: refinement of the Effects of Prostate Cancer Upon Lifestyle Questionnaire and an initial exploration of its links with anxiety and depression among prostate cancer patients
Authors: Sharpley Christopher F. , Bitsika Vicki , Christie David R. H. 
Published: September 2009

AbstractObjective: To psychometrically refine a standardized scale for identifying those lifestyle changes that were most likely to contribute to anxiety and depression among prostate cancer (PCa) patients.Methods: Three hundred and eighty‐one PCa patients who had received their initial diagnosis between one and 96 months completed a survey of background variables, anxiety and depression inventories and the 36‐item Effects of Prostate Cancer upon Lifestyle Questionnaire (EPCLQ).Results: Levels of anxiety (24%) and depression (26%) were similar to those previously reported for PCa patients. The EPCLQ was shown to have satisfactory psychometric properties and significantly predicted anxiety and depression scores and the presence of psychological clinicity among this sample. Factor analysis of the EPCLQ showed that adverse emotions and social withdrawal, plus loss of cognitive ability, were the most powerful predictors of fear, physiological arousal, discomfort and pain factors underlying anxiety; these factors also predicted pessimism and fatigue factors underlying depression.Conclusions: The EPCLQ was shown to be a reliably sound and valid instrument for assessing important lifestyle changes that predict anxiety and depression among PCa patients. In addition, links between receiving a diagnosis and treatment for PCa and development of psychosocial disturbance via emotional negativity, decreased cognitive performance and withdrawal from others appear to warrant further investigation. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis of the Ammonium Salt of 6‐Amino‐2‐hydroxy‐ 3,5‐dinitropyrazine and a Comparison of its Properties with those of Ammonium 3,5‐Diaminopicrate (ADAP)
Authors: Bellamy Anthony J. , Contini Alessandro E. , Padfield James , Golding Peter , Mahon Mary F. 
Published: September 2009

AbstractThe ammonium salt of 6‐amino‐2‐hydroxy‐3,5‐dinitropyrazine has been synthesised from 2,6‐dimethoxy‐3,5‐dinitropyrazine and its properties (DSC, crystal structure, impact sensitiveness and thermochemical properties) are compared with the analogous benzene derivative, ammonium 3,5‐diaminopicrate.
Taproot™ technology: Tree coring for fast, noninvasive plume delineations
Authors: Burken Joel G. , Bailey Sallie , Shurtliff Matt , McDermott Jeff 
Published: September 2009

AbstractIn efforts to evaluate the use of plants as a forensic tool for delineating contaminated soil and groundwater, a laboratory experiment and a field sampling effort were undertaken. Site assessments are often costly and inaccurate, requiring multiple mobilizations to hone in on source areas and getting accurate estimates of contaminant extent and distribution. As these extensive site delineations take place, valuable time and resources are lost. The findings of this study show that plants can be used as a tool to evaluate a variety of subsurface contaminants, either in the vadose zone or in the saturated zone.In the first field application of Taproot™ Technology, a large, heavily forested site was sampled in one day and the contamination on‐site was more accurately delineated than had been generated at the site in over a decade, with more than 26 wells installed. New source zones were detected on the site, and the presence of new waste depositions was uncovered for the first time showing the great value of tree coring as a contaminant detection tool. © 2009 Wiley Periodicals, Inc.
In‐well sediment incubators to evaluate microbial community stability and dynamics following bioimmobilization of uranium
Authors: Baldwin Brett R. , Peacock Aaron D. , (Margaret) Gan Ying‐Dong , Resch C. Tom , Arntzen Evan , Smithgall Amanda N. , Pfiffner Susan M. , Freifeld Barry M. , White David C. , Long Philip E. 
Published: September 2009

AbstractAn in‐well sediment incubator (ISI) was developed to investigate the stability and dynamics of sediment‐associated microbial communities to prevailing subsurface oxidizing or reducing conditions. Herein we describe the use of these devices at the Old Rifle Uranium Mill Tailings Remedial Action (UMTRA) site. During a seven‐month period in which oxidized Rifle Aquifer background sediment (RABS) were deployed in previously biostimulated wells under iron‐reducing conditions, cell densities of known iron‐reducing bacteria, including Geobacteraceae, increased significantly, showing the microbial community response to local subsurface conditions. Phospholipid fatty acid (PLFA) profiles of RABS following in situ deployment were strikingly similar to those of adjacent sediment cores, suggesting ISI results could be extrapolated to the native material of the test plots. Results for ISI deployment with laboratory‐reduced sediments showed only slight changes in community composition and pointed toward the ability of the ISI to monitor microbial community stability and response to subsurface conditions. © 2009 Wiley Periodicals, Inc.
Reactive transport modeling of remedial scenarios to predict cadmium, copper, and zinc in north fork of Clear Creek, Colorado
Authors: Butler Barbara A. , Caruso Brian S. , Ranville James F. 
Published: September 2009

AbstractThe North Fork of Clear Creek (NFCC), Colorado, is an acid‐mine‐drainage‐impacted stream typical of many mountain surface waters affected by historic metal mining in the western United States. The stream is devoid of fish primarily because of high metal concentrations in the water (e.g., copper and zinc) and has large amounts of settled iron oxyhydroxide solids that coat the streambed. The NFCC is part of the Central City/Clear Creek Superfund site, and remediation plans are being implemented that include treatment of three of the main point‐source inputs and cleanup of some tailings and waste rock piles. This article examines dissolved (0.45‐μm filterable) concentrations of cadmium, copper, and zinc following several potential remediation scenarios, simulated using a reactive transport model (WASP4/META4). Results from modeling indicate that for cadmium, remediation of the primary point‐source adit discharges should be sufficient to achieve acute and chronic water‐quality standards under both high‐ and low‐flow conditions. To achieve standards for copper and zinc, however, the modeling scenarios suggest that it may be necessary to treat or remove contaminated streambed sediments in downstream reaches, as well as identify and treat nonpoint sources of metals. Recommendations for improvements to the model for metal transport in acid‐mine drainage impacted streams are made. These recommendations are being implemented by the U.S. Environmental Protection Agency. © 2009 Wiley Periodicals, Inc.
Does loyalty protect Chinese workers from stress? The role of affective organizational commitment in the Greater China Region
Authors: Lu Luo , Siu Oi‐Ling , Lu Chang‐Qin 
Published: September 2009

AbstractThe aim of this research was to test the direct and moderating effects of affective organizational commitment (AOC) on the work stressors—job satisfaction relationship among employees in the Greater China Region. A self‐administered survey was conducted to collect data from three major cities in the region, namely Beijing, Hong Kong and Taipei (n = 380). Three most important work stressors were assessed: heavy workload, lack of work autonomy and interpersonal conflict. We found that both work stressors and AOC were related to job satisfaction. Specifically, heavy workload, lack of autonomy and interpersonal conflict were negatively related to job satisfaction; whereas, AOC had a positive relation with job satisfaction. Furthermore, AOC moderated the interpersonal conflict—job satisfaction and the lack of autonomy—job satisfaction relationships. The present study thus found joint effects of work stressors and AOC (as buffers) on work attitudes among Chinese employees in the Greater China Region, encompassing three sub‐societies of mainland China, Hong Kong and Taiwan. Copyright © 2009 John Wiley & Sons, Ltd.
VERB™ Summer Scorecard: Findings from a Multi‐level Community‐based Physical Activity Intervention for Tweens
Authors: DeBate Rita D. , Baldwin Julie A. , Thompson Zachary , Nickelson Jen , Alfonso Moya L. , Bryant Carol A. , Phillips Leah M. , McDermott Robert J. 
Published: September 2009

AbstractThe benefits of physical activity for adolescents are well established. Multi‐level interventions may be especially effective in establishing and sustaining health‐enhancing behaviors. This study explored the influences of a multi‐level community intervention aimed at increasing physical activity among tweens (youth 9–13). Two Florida school districts far apart served as intervention and comparison sites in a quasi‐experimental post‐test design. Youth in grades 5 through 8 in the intervention community (n = 1,253) and comparison community (n = 866) completed an anonymous post‐intervention survey. An intent‐to‐treat analysis did not show any statistically significant group differences for the physical activity outcomes examined. However, a subset analysis revealed that students who reported participating in the intervention were more likely to be physically active than youth in the comparison group, as well as youth in the intervention community who reported not participating. Participating in the intervention was significantly related to meeting recommendations for vigorous physical activity (OR = 2.08, P = 0.0259), being physically active on weekends (OR = 1.84, P = 0.0017), and reporting more days of trying a new game or sport (OR = 1.49, P = 0.046) after controlling for grade, gender, race/ethnicity, and SES. These findings support the efficacy of multi‐level interventions to create effective health behavior change, especially when linkages among community, media, schools, and the home are present.
Suppression in Mevalonate Synthesis Mediates Antitumor Effects of Combined Statin and γ‐Tocotrienol Treatment
Authors: Wali Vikram B. , Bachawal Sunitha V. , Sylvester Paul W. 
Published: September 2009

AbstractStatins directly inhibit 3‐hydroxy‐3‐methylglutaryl‐coenzyme A reductase (HMGR) activity, while γ‐tocotrienol, an isoform of vitamin E, enhances the degradation and reduces cellular levels of HMGR in various tumor cell lines. Since treatment with statins or γ‐tocotrienol alone induced a dose‐responsive inhibition, whereas combined treatment with subeffective doses of these agents resulted in a synergistic inhibition in +SA mammary tumor cell growth, studies were conducted to investigate the role of the HMGR pathway in mediating the antiproliferative effects of combined low dose statin and γ‐tocotrienol. Treatment with 8 μM simvastatin inhibited cell growth and isoprenylation of Rap1A and Rab6, and supplementation with 2 μM mevalonate reversed these effects. However, the growth inhibitory effects of 4 μM γ‐tocotrienol were not dependent upon suppression in mevalonate synthesis. Treatment with subeffective doses of simvastatin (0.25 μM), lovastatin (0.25 μM), mevastatin (0.25 μM), pravastatin (10 μM), or γ‐tocotrienol (2 μM) alone had no effect on protein prenylation or mitogenic signaling, whereas combined treatment with these agents resulted in a significant inhibition in +SA cell growth, and a corresponding decrease in total HMGR, Rap1A and Rab6 prenylation, and MAPK signaling, and mevalonate supplementation reversed these effects. These findings demonstrate that the synergistic antiproliferative effects of combined low dose statin and γ‐tocotrienol treatment are directly related to an inhibition in HMGR activity and subsequent suppression in mevalonate synthesis.
On completely singular von Neumann subalgebras
Authors: Fang Junsheng 
Published: September 2009

AbstractLet ℳ be a von Neumann algebra acting on a Hilbert space $\mathcal{H}$ and let $\mathcal{N}$ be a von Neumann subalgebra of ℳ. If $\mathcal{N}\operatorname{\bar{\otimes}}\mathcal{B}(\mathcal{K})$ is singular in $\mathcal{M}\operatorname{\bar{\otimes}}\mathcal{B}(\mathcal{K})$ for every Hilbert space $\mathcal{K}$, $\mathcal{N}$ is said to be completely singular in ℳ. We prove that if $\mathcal{N}$ is a singular abelian von Neumann subalgebra or if $\mathcal{N}$ is a singular subfactor of a type-II1 factor ℳ, then $\mathcal{N}$ is completely singular in ℳ. $\mathcal{H}$ is separable, we prove that $\mathcal{N}$ is completely singular in ℳ if and only if, for every θ∈Aut($\mathcal{N}$′) such that θ(X)=X for all X ∈ ℳ′, θ(Y)=Y for all Y∈$\mathcal{N}$′. As the first application, we prove that if ℳ is separable (with separable predual) and $\mathcal{N}$ is completely singular in ℳ, then $\mathcal{N}\operatorname{\bar{\otimes}}\mathcal{L}$ is completely singular in $\mathcal{M}\operatorname{\bar{\otimes}}\mathcal{L}$ for every separable von Neumann algebra $\mathcal{L}$. As the second application, we prove that if $\mathcal{N}$1 is a singular subfactor of a type-II1 factor ℳ1 and $\mathcal{N}$2 is a completely singular von Neumann subalgebra of ℳ2, then $\mathcal{N}_1\operatorname{\bar{\otimes}}\mathcal{N}_2$ is completely singular in $\mathcal{M}_1\operatorname{\bar{\otimes}}\mathcal{M}_2$.