bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation and characterization of polyaniline/MMT conductive composites
Authors: Liu Chenxiang , Zhou Yuanyuan , Li Song , Li Lei , Yu Min 
Published: September 2008

AbstractPolyaniline/montmorillonite (PAn/MMT) composite material has been prepared through chemical‐oxidative polymerization by using NH4S2O8 as the oxidant, and it was found that both the composites have inorganic and organic material characteristics and many outstanding performance through the copolymerization coupling of MMT and polyaniline. Infrared spectroscopy (FT‐IR), thermogravimetric analysis (TGA), X‐ray diffraction (XRD), and transmission electron microscopy (TEM) are used to characterize the composition and structures of composite materials, as well as test the conductivity of composite materials through a four‐probe technique. The preparation conditions of PAn/MMT conducting composites are optimized. The optimal conditions have been identified for the reaction time, amount of oxidizer, concentration of HCl, and the amount of MMT. Besides, the results show that when the reaction lasts for 8 hr in the ice bath, the amount of MMT is 0.4 g/5 ml An, the mole ratio of oxidant to aniline is 1, and the concentration of hydrochloric acid is 2 M, the composite had the largest conductivity up to 11.5 S/cm. In addition, we also did an elemental analysis of the composite mechanism of PAn/MMT composites. Copyright © 2008 John Wiley & Sons, Ltd.
Structural and vibrational study of 2‐(2′‐furyl)‐1H‐imidazole
Authors: Ledesma A. E. , Brandán S. A. , Zinczuk J. , Piro O. E. , González J. J. López , Altabef A. Ben 
Published: September 2008

AbstractThe 2‐(2′‐furyl)‐1H‐imidazole (1) has been prepared and characterized using infrared, Raman, and multidimensional nuclear magnetic resonance spectroscopies. Two conformations of this species obtained by rotation of 180°, approximately, around the CC inter‐ring bond are detected. Likewise, the crystal and molecular structure of1has been analyzed by X‐ray diffraction methods and it evidenced that both conformations are present in the lattice with equal occupancy and linked in alternate way to the NH‐‐‐N bonded polymeric chains along the crystal [101] direction. Theoretical calculations have been carried out by employing the density functional theory (DFT)/B3LYP method, in order to optimize the geometry in gas phase of both conformers and to support the assignments of the vibrational bands of1to their normal modes. For a complete assignment of the compound, DFT calculations were combined with Pulay's SQMFF methodology in order to fit the theoretical frequency values to the experimental one. The nuclear magnetic resonance spectrum observed for1is successfully compared with the calculated chemicals shifts at B3LYP/6‐311++G** level of theory for the two conformers. Furthermore, natural bond orbital (NBO) analysis and topological (AIM) calculations for an oligomer, containing three alternated units of the NH‐‐‐N bonded chain found in the crystal, reveals the characteristics of the hydrogen bonds present in the polymeric structure. Copyright © 2008 John Wiley & Sons, Ltd.
Exploring preferential association of laponite and cloisite with soft and hard segments in TPU‐clay nanocomposite prepared by solution mixing technique
Authors: Mishra A. K. , Nando G. B. , Chattopadhyay S. 
Published: September 2008

AbstractThermoplastic polyurethane (TPU) is a versatile polymer exhibiting many engineering applications. In this article, two varieties of clay (Cloisite and Laponite RD) have been used to prepare TPU‐based nanocomposites. They differ in, chemical composition, hydrophobicity, aggregation tendency, and dispersibility in a particular solvent. A detailed investigation of the thermal, morphological, and rheological behavior reflects the affinity of Cloisite towards the soft segment, whereas it is the hard segment for modified Laponite. The maximum improvement in onset degradation temperature has been observed to be 17.5 and 8.3 °C for Cloisite and Laponite, respectively. Five percent Cloisite‐filled sample shows optimum storage modulus in the glassy region where as it is the 10% filled sample at the rubbery region. However, the trend remains indifferent both in rubbery and glassy regions for Laponite, and properties have been found optimum for 3% filled sample. To explore the behavior in the terminal and flow regions, dynamic rheological experiments were performed in low shear rate. Variation in dynamic rheological properties can be explained well on the basis of the combination of partly exfoliated, intercalated, and aggregated structures of the nano clay inside the TPU matrix, depending on their nature and preferential association with different segments. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2341–2354, 2008
Effects of chain configuration on UCST behavior in blends of poly(L‐lactic acid) with tactic poly(methyl methacrylate)s
Authors: Li Shu‐Hsien , Woo Eamor M. 
Published: September 2008

AbstractChain configuration influences phase behavior of blends of poly(methyl methacrylate) (PMMA) of different tactic configurations (syndiotacticity, isotacticity, or atacticity) with poly(L‐lactic acid) (PLLA). Blends system of sPMMA/PLLA is immiscible with an asymmetry‐shaped UCST at ∼250 °C. The phase behavior of the sPMMA/PLLA blend is similar to the aPMMA/PLLA blend that has been already proven in the previous work to exhibit similar UCST temperatures (230–250 °C) and asymmetry shapes in the UCST diagrams. On the other hand, the iPMMA/PLLA blend remains immiscible up to thermal degradation without showing any transition to UCST upon heating. The blend system with UCST, that is, sPMMA/PLLA, can be frozen in a state of miscibility by quenching to rapidly solidify from the homogeneous liquid at UCST, where the Tg‐composition relationship for the sPMMA/PLLA blend fits well with the Gordon‐Taylor Tg model with k = 0.15 and the blend's T leads to χ12 = −0.26 for the UCST‐quenched sPMMA/PLLA blend. Both parameters (k and χ) as characterized for the frozen miscible blend suggest a relatively weak interaction between the two constituents (sPMMA and PLLA) in the blends. The interaction strength is likely not strong enough to maintain a thermodynamic miscibility when the blend is at ambient temperature or any lower temperatures below UCST. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2355–2369, 2008
New insight into the crystallization behavior of poly(ethylene terephthalate)/clay nanocomposites
Authors: Guan Guohu , Li Chuncheng , Yuan Xuepei , Xiao Yaonan , Liu Xiaoqing , Zhang Dong 
Published: September 2008

AbstractCrystallization behavior of poly(ethylene terephthalate) (PET)/clay nanocomposites has been investigated in terms of differential scanning calorimeter (DSC) analysis, polarizing optical microscopy (POM), and scanning electron microscopy (SEM) observation. The nanocomposites for investigation were prepared via in situ polycondensation. Crystalline morphologies were observed through POM and SEM. The nonisothermal and isothermal crystallization rates of different samples were determined for comparison based on DSC data. Secondary nucleation analysis was also performed based on bulk crystallization data derived from DSC analysis. The results revealed that nucleating abilities of montmorillonites (MMT) depended on the dispersion state of clay in matrix, the surface modification status, and the metallic derivatives released from MMT during in situ synthesis. The quantities of metallic elements released were measured by inductively coupled plasma (ICP) analysis. The results showed that the release of these metallic derivatives was also affected by surfactant molecules anchored on the surface of MMT. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2380–2394, 2008
Personality predicts prostate cancer treatment decision‐making difficulty and satisfaction
Authors: Orom Heather , Penner Louis A. , West Brady T. , Downs Tracy M. , Rayford Walter , Underwood Willie 
Published: September 2008

AbstractObjective: Prostate cancer (PCa) patients often must decide between several treatment modalities considered equally efficacious, but associated with different benefits and side‐effects. For some, the decision‐making process can be difficult, but little is known about patient characteristics and cognitive processes that might influence the difficulty of such decisions. This study investigated the roles of dispositional optimism and self‐efficacy in PCa treatment decision‐making difficulty and satisfaction.Methods: One hundred and twenty‐five patients with clinically localized PCa completed a mail‐in paper‐and‐pencil survey after they had made their treatment decision, but prior to treatment.Results: After adjusting for covariates, optimism and treatment decision‐making self‐efficacy were associated with less difficulty and greater satisfaction with the treatment decision‐making process. Effects of optimism on difficulty and satisfaction were partially mediated by self‐efficacy for making the treatment decision.Conclusions: Men with PCa and who are low in optimism may be at greater risk for treatment decision‐making difficulty and lack of treatment decision‐making satisfaction, in part, because they have lower confidence in their ability to make the decision compared with those who are more optimistic. As self‐efficacy perceptions are modifiable, consideration should be given to including self‐efficacy enhancing components as part of PCa treatment decision‐making interventions. Copyright © 2008 John Wiley & Sons, Ltd.
NFPA's hydrogen technologies code project
Authors: Rivkin Carl H. 
Published: September 2008

AbstractThis article discusses the development of National Fire Protection Association 2 (NFPA), a comprehensive hydrogen safety code. It analyses the contents of this document with particular attention focused on new requirements for setting hydrogen storage systems. These new requirements use computational fluid dynamic modeling and risk assessment procedures to develop requirements that are based on both technical analyses and defined risk criteria. The intent is to develop requirements based on procedures that can be replicated based on the information provided in the code document. This code will require documentation of the modeling inputs and risk criteria and analyses in the supporting information.This article also includes a description of the codes and standards that address hydrogen technologies in general. © 2008 American Institute of Chemical Engineers Process Saf Prog, 2008
Procedural‐based controls in layer of protection analysis
Authors: Freeman Raymond “Randy” 
Published: September 2008

AbstractThe Center for Chemical Process Safety (CCPS) book on the LOPA (layer of protection analysis) methodology gives little credit for procedural controls. In batch operations, startups or process shutdowns, the procedural controls are often the only available means of controlling the potential hazards. This article presents a methodology for the evaluation of procedural‐based controls as potential independent layers of protection during a LOPA study. A checklist for the evaluation of procedural controls is presented as well as a few examples to demonstrate the methodology. © 2008 American Institute of Chemical Engineers Process Saf Prog, 2008
Improved process safety management and simple metrics
Authors: Chosnek Jack , Clifton Ricky 
Published: September 2008

AbstractA Process Safety Management (PSM) system was recently implemented at Gulf Coast Waste Disposal Authority (GCWDA). This approach enabled management of increased process risks. These increased risks were brought about by the introduction of large quantities of oxygen for the processing of chemical waste and the destruction of emissions in Regenerative Thermal Oxidizers. This was a voluntary effort by GCWDA, since they do not fall under the OSHA PSM Standard (29 CFR 1910.119).A tailored PSM system was developed that could comply with the OSHA Standard. This PSM system also included additional elements that are considered improvements on OSHA elements. These additional elements are utilized by some leading U.S. chemical manufacturing companies. These additional elements included Management Commitment, Management Review, Conduct of Operations and Continuous Improvement.Simple metrics were created for selected PSM elements, in order to allow for continuous and proactive management review. These metrics supplemented periodic audits and replaced reliance on the common use of incident statistics.This article will deal with the implementation of the PSM system from both the perspectives of the consultant that assisted in the implementation and the facility management that managed the implementation. The successes and some of the barriers for implementation in a small company will also be discussed, as well as the management success in the year after its implementation. © 2008 American Institute of Chemical Engineers Process Saf Prog, 2008
Energy transfer processes among emitters dispersed in a single polymer layer for colour tuning in OLEDs
Authors: Georgiadou D. G. , Vasilopoulou M. , Pistolis G. , Palilis L. , Dimotikali D. , Argitis P. 
Published: September 2008

AbstractThe energy transfer processes taking place in a single polymeric layer that enable the definition of the three primary colours (red, green and blue) in selected areas via photochemically induced emission tuning are discussed. The polymers used as hosts are two wide band gap polymers, PVK and a polyfluorenyl derivative. In the polymer matrix are dispersed the green emitter, 1‐(4′‐dimethyl‐aminophenyl)‐6‐phenyl‐1,3,5‐hexatriene (DMA‐DPH), the red emitter, 4‐dimethylamino‐4′‐nitrostilbene (DANS) and a photoacid generator (PAG). Upon irradiation, protons are released from the PAG and they react gradually with the two emitters, causing the blue shift of the green emitter fluorescence and the extinction of the red emitter fluorescence. Depending on the protonation extent, the relative concentrations of the emitters and the exposure dose the energy transfer processes occurring inside the matrix result in definition of different colour emitting areas. The understanding of the energy transfer processes with photoluminescence experiments is a necessary first step in order to rationalize the selection of suitable components enabling the definition of the three primary colours in OLEDs. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tensile properties of shape memory alloy chiral honeycombs
Authors: Hassan M. R. , Scarpa F. , Mohamed N. A. , Ruzzene M. 
Published: September 2008

AbstractThe tensile properties of hexachiral honeycomb made of shape memory alloy (SMA) material are modelled and verified experimentally at different tensile loading and ambient temperature conditions. The numerical models describe the temperature‐pseudoelastic behaviour of the shape memory alloy materials constituted by Ni48Ti46Cu6 alloy. Parametric analysis on the Poisson's ratio effects over large strain deformation and temperature conditions are performed, as well as the analysis of the dependence of the honeycomb stress‐strain behaviour under uniaxial loading with temperature varying through the shape memory alloy phase transformation. Chiral SMA honeycomb samples are manufactured and tested under similar environmental conditions. The experimental results are compared with the numerical one, showing good convergence in terms of trends and overall quantitative values. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Responses of litter decomposition to temperature along a chronosequence of tropical montane rainforest in a microcosm experiment
Authors: He Xingbing , Zhang Peng , Lin Yonghui , Li Airong , Tian Xingjun , Zhang Qing‐He 
Published: September 2008

AbstractWe conducted a microcosm experiment for studying the decomposition of Altingia obovata leaf litter by the decomposer community at 20 and 30°C from three forest stands (namely a 35‐year‐old secondary forest, a 47‐year‐old secondary forest, and a primary forest) of a tropical montane rainforest. Our results showed that rank‐order of the litter decomposition among the three forest stands was not parallel to the stand age. At 20°C, the mass loss of A. obovata leaf litter from the primary forest was higher than those from the two secondary forests, of which the younger stand showed higher mass loss than did the older one. However, there were no differences in mass loss among these three stands at 30°C. The mass loss for the two secondary forest stands, but not for the primary forest stand, increased significantly from 20 to 30°C. The level of lignin decomposition among the three stands at 20°C corresponded to their forest stand age, i.e., the primary forest > the 47‐year‐old secondary forest > the 35‐year‐old secondary forest. A rise of 10°C in temperature significantly increased lignin decomposition for the two secondary forests, while the reverse was true for the primary forest. Carbohydrate decomposition was positively related to the temperature but not to the stand age. The different responses of litter decomposition to the forest stand age and temperature might be due to the differences in the microbial activities among the three forest stands.
Monitoring of Fat Content, Free Fatty Acid and Fatty Acid Profile Including trans Fat in Pakistani Biscuits
Authors: Kandhro Aftab , Sherazi S. T. H. , Mahesar S. A. , Bhanger M. I. , Talpur M. Younis , Arain Sarfraz 
Published: September 2008

AbstractThe fat contents of 12 brands of biscuits were extracted and evaluated for free fatty acids (FFA) and their fatty acid composition (FAC). The oil content and FFA varied from 13.7 to 27.6% and 0.2 to 1.0%, respectively. The FAC was analyzed by gas chromatography–mass spectroscopy with particular emphasis on trans fatty acids (TFA). Total saturated, unsaturated, cis‐monounsaturated and polyunsaturated fatty acids were determined in the range of 37.9–46.9, 53.0–62.0, 12.3–43.7 and 0.1–9.2%, respectively. The high amount of TFA was observed in all biscuit samples and varied from 9.3 to 34.9%. The quantity and quality of the lipid fraction of the biscuits indicated that the all analyzed biscuits are a rich source of fat, saturated fatty acids and trans fatty acids, consequently not suitable for the health of consumers. The high content of trans fatty acids and palmitic acid also indicated that blends of RBD palm oil and partially hydrogenated oil had been used in the biscuit manufacturing.
Prospective prenatal serum screening for Down syndrome in Venezuela
Authors: Álvarez‐Nava Francisco , Soto Marisol , Morales‐Machín Alisandra , Rojas Alicia , Urdaneta Karelis , Cañizález Jenny 
Published: September 2008

AbstractObjectiveTo assess the usefulness of triple‐marker screening for Down syndrome in Venezuela.MethodMaternal serum concentrations of alpha fetoprotein (AFP), beta human chorionic gonadotropin (β‐hCG), and unconjugated estriol (uE3) were measured weekly in 3895 women from the 15th to the 20th week of pregnancy. Population‐specific likelihood ratios were determined and used to calculate the risk of fetal Down syndrome for each pregnancy.ResultsThe median multiple of the median values for AFP, β‐hCG, and uE3 concentrations were 0.69, 2.10, and 0.67 for the affected pregnancies. The likelihood ratio for a positive result was 1:19. The detection and false‐positive rates were 69.23% and 5.8%.ConclusionThese findings were consistent with reported data and therefore confirmed triple‐marker serum screening as effective and suitable for prenatal care in Venezuela. Latin American governments and Health Agencies should recommend offering this screening method to all pregnant women.
The beginning of the year in England,c.500–900
Authors: Harrison Kenneth 
Published: September 2008

Writing a little before the year 1000, Ælfric in a homily on the Feast of the Circumcision (1 January) had this to say about the beginning of the year:We have often heard that men call this day ‘the day of the year’, as if this day were foremost in the year's circuit; but we find no explanation in Christian books, why this day is accounted the beginning of the year. The old Romans, in heathen days, began the year's circuit on this day; and the Hebrew people at the vernal equinox; the Greeks on the summer solstice; and the Egyptian nations began the reckoning of their year at harvest. Now our reckoning begins, according to the Roman institution, on this day, for no religious reason, but for the old custom. Some of our servicebooks begin on the Lord's Advent; yet it is not on that account the beginning of the year.
King Alfred's æstel
Authors: Harbert Bruce 
Published: September 2008

King Alfred's preface to the Old English Pastoral Care, explaining how and why he made this translation from the original of Gregory the Great, ends thus:Siððan ic hie geliornod hæfde, swæ swæ ic hie forstod, ond swæ ic hie andgitfullicost areccean meahte, ic hie on Englisc awende; ond to ælcum biscepstole on minum rice wille ane onsendan; ond on ælcre bið an æstel, se bið on fiftegum mancessa.
Cuthswith, seventh-century abbess of Inkberrow, near Worcester, and the Würzburg manuscript of Jerome on Ecclesiastes
Authors: Sims-Williams Patrick 
Published: September 2008

The fifth-century Italian manuscript of Jerome's Commentary on Ecclesiastes, Würzburg, Universitätsbibliothek, M. p. th. q. 2, which M. Adriaen takes as the base of his recent edition, is interesting to English scholars on various counts. On ir it bears a very early Old English inscription, in Anglo-Saxon majuscule which Lowe and Bischoff date c. 700:Cuthsuuithae. boec.thaerae abbatissan.(‘a book of Cuthswith the abbess’). In all probability this was written in England itself rather than at an Anglo-Saxon centre on the continent, in view of the chronology of the English missions. The commentary is in ‘a beautiful bold uncial of the oldest type’, but six leaves of the manuscript's original 114 (fols. 10, 13, 63, 68, 81 and 82) were replaced by leaves of a thicker parchment, in England according to Lowe and Bischoff. It is not known why this was necessary, nor where the text was taken from. Lowe dates the writing of these later leaves to the seventh century. He observes that they were ‘written, if one may judge from the syllable-by-syllable copying, by a scribe for whom Latin was an alien tongue and who was not completely sure of his uncial characters’. D. H. Wright remarks that their example of an English scribe ‘doing his unequal best to reproduce the unfamiliar letter forms’ is not a very helpful illustration of the relationship of English uncial to Italian models, ‘for the script he writes has no style of its own, and therefore no future’. The main interest of the manuscript in the history of English uncial is as an illustration of foreign models which were available; it is, in Lowe's words, ‘the oldest extant uncial manuscript that was at hand to serve as a model in an English scriptorium’.