bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Monitoring of an Eroding Prehistoric Site at Achnasavil,Carradale, Kintyre.
Authors: Siggins Gloria , Carter Stephen 
Published: February 2011

Summary Recent changes in the course of the Carra Water have revealed archaeological features in the river bank at Achnasavil, Carradale. They include pits, post-holes or slots and hearths probably of late Bronze Age and early Iron Age date.
Excavations at the Roman fort of Barochan Hill, Renfrewshire, 1972 and 1984-1986
Authors: Keppie Lawrence , Newall Frank 
Published: February 2011

SummaryLimited excavation combined with ground observation and the study of aerial photographs has established the area of the fort as c. 1.44 ha (3.55 acres). The defences were examined on the S and W sides, and two gates located. The intervallum space near both gates had seen intense occupation. Timberframed buildings lay behind the West Gate. The pottery, some of it made locally, and other small finds indicated occupation in the Flavian period of the later 1st century AD, from c. AD 80 onwards, a dating which the excavation's only coin find, a probable As of AD 86, served to confirm. The lifespan of the fort was short, probably no more than a decade, during which modifications to the defences and internal buildings occurred.
Excavation of a grain-drying kiln and mill lade at Kettlestoun Mains, Linlithgow, West Lothian
Authors: Alexander Derek 
Published: February 2011

SummaryThe Centre for Field Archaeology is contracted to undertake archaeological monitoring of a six year gravel extraction programme at Kettlestoun Mains, Linlithgow. In the first year of this project, the remains of a grain-drying kiln, containing charred oat seeds and chaff, and a mill lade were excavated. Both of these structures contained post-medieval pottery and represent parts of a wider post-medieval landscape revealed by analysis of documentary evidence.
Training Novices to Make Expert, Occupationally Focused, Community Mental Health Referral Decisions
Authors: Harries Priscilla , Gilhooly Kenneth 
Published: February 2011

Introduction: Currently, British health policy requires services to be prioritised according to an individual's level of need. This is particularly necessary for community mental health services, where referral demand far exceeds service availability. Purpose: The purpose of this study was to use expert occupational therapists' referral prioritisation policies, derived from judgement analysis, to train novices in the skill of referral prioritisation. Method: The therapists' policies chosen were those that supported the occupationally focused practice advocated by the profession. Thirty-seven pre-registration students were asked to prioritise a set of referrals, before and after being trained with graphical and descriptive representations of these experts' policies. Findings: Pre-training, the students overvalued the client's history of violence and undervalued the reason for referral and the client's diagnosis, as compared with the experts. Post-training, the students' policies were better matched to those of the experts. The effect of training was demonstrated through several measures: more accurate prioritisation scores when matched with expert ratings on the same referrals, improved consistency on repeat referrals and higher group agreement. Conclusion: Decision training may be useful in promoting the type of service that aims to target clients' occupational needs in the field of community mental health.
Nano-Structural Elucidation in Carbon Black Loaded NR Vulcanizate by 3D-TEM and In Situ WAXD Measurements
Authors: Ikeda Yuko , Kato Atsushi , Shimanuki Junichi , Kohjiya Shinzo , Tosaka Masatoshi , Poompradub Sirilux , Toki Shigeyuki , Hsiao Benjamin S. 
Published: February 2011

Abstract
Three dimensional (3D) visualization of nanometer structure of carbon black dispersion in rubbery matrix has successfully been studied and reported in this paper. Use of 3D-TEM, which is computerized tomography combined with transmission electron microscopy (TEM), enabled us to reconstruct 3D images of carbon black aggregates in natural rubber (NR) matrix. The TEM measurements were conducted by a bright-field method on thin samples without any electron staining. The sample was subject to uni-axial tilting (+65 degree to −65 degree with 2 degree increment) in the sample chamber, and 66 TEM images were taken on each sample. These TEM images were used for computerized tomography to reconstruct the 3D image. This technique is designated as 3D-TEM. The nano-structural features observed by 3D-TEM were in conformity with the electron-conductivity results, and the percolation behavior was recognized. These results were further supplemented by in situ wide-angle X-ray diffraction (WAXD), i.e., simultaneous WAXD and tensile measurements on the sample to observe the strain-induced crystallization in NR vulcanizate. Upon tensile elongation, the crystallization was clearly observed in WAXD in the presence of carbon black, and it contributed to the tensile properties. In order to understand the performances of filled NR vulcanizates, it surely is necessary to know the structural states of the mixed nano-filler and the crystallites produced upon elongation.
Mechanistic Study on the Role of Sulfurized Para-Aramid Short Fibers in Rubber to Brass Adhesion
Authors: Datta R. N. 
Published: February 2011

Abstract
Adhesion between steel cord and rubber is an important factor determining the durability of tires, conveyer belts, hoses and other rubber based products using steel cord as reinforcement. With the advancement in tire technology, steel reinforced radial tires have captured 90–95% of the tire market in most of the advanced countries and brass coated steel cord has been established as the premium carcass and belt material for radial truck tires. Apart from the use of cobalt salts to improve adhesion, the adhesion characteristics can also be improved through the use of resin systems such as resorcinol/hexamethoxymethyl melamine (R/HMMM), often together with silica as a partial replacement for carbon black. This combination accomplishes several things. It acts as a modulus and hardness enhancer providing a more compatible system with regard to the stiffness of the steel cord compared to that of the cured skim compound. Secondly, the combination can improve resistance to the negative effects of humidity on adhesion. Thirdly, the pro-oxidant effect of cobalt salts is counteracted to some degree. There is, however, a drawback with regard to this resin system; resorcinol generates toxic fumes at high temperatures encountered during mixing and processing. There is demand, therefore, to replace the R/HMMM adhesion system due to health and safety issues. This paper presents the results of studies to achieve adequate steel cord adhesion whilst seeking to improve aged compound characteristics and to reduce compound heat build up through the use of sulfurized para-aramid short fibers. This combination not only improves the properties of steel cord skim compounds, but also can be used effectively to replace the bonding system based on resorcinol and hexamethoxymethylmelamine. Further studies were carried out in squalene model to elucidate the changes in the chemistry of vulcanization both in the presence and absence of sulfurized p-aramid short fibers. Additional studies were carried out on sulfidized brass cords to analyze the adhesion layer's elemental composition using the Electron Dispersive X-ray Spectroscopy (EDX) characterization techniques.
Modeling of the Linear Viscoelastic Behavior of Partially Hydrogenated Polymer-Modified Asphalts
Authors: Vargas M. A. , Herrera R. , Manero O. 
Published: February 2011

Abstract
The modeling of the linear viscoelastic behavior of asphalt modified with 8 wt % of partially hydrogenated poly (styrene-butadiene-styrene) triblock copolymers is analyzed. Time-temperature superposition renders master curves in a wide range of frequencies and temperatures, from which a logarithmic distribution of relaxation times is obtained using the multimode Maxwell model. In addition, the linear viscoelastic data is analyzed with an emulsion model and agreement is only found at high frequencies, where the contribution from interfacial tension is negligible. Enhanced polymer-asphalt interactions at low frequencies evidenced by a decreasing limiting slope of the storage modulus in the terminal region are not predicted by the emulsion model, and relative agreement is found considering two viscoelastic phases. The Cole-Cole representation and the fractional Maxwell model predict the viscosity of asphalt in the complex plane, but strong asymmetry in the semicircular arcs is found in the polymer-modified asphalt blends. The Havriliak-Negami model accounts for asymmetric arcs and represents the data better in specific ranges of frequency.
Molecular Mobility of Unfilled and Carbon-Black-Filled Isoprene Rubber: Proton NMR Transverse Relaxation and Diffusion
Authors: Sun Ximei , Isayev Avraam I. , Joshi Tirtha R. , von Meerwall Ernst 
Published: February 2011

Abstract
In an effort to understand the effect of ultrasound on the devulcanization of gum and filled isoprene rubber vulcanizates, solid state NMR 1H transverse relaxation (T2) was employed to analyze rubber molecular mobility. The T2 relaxation decay of the unfilled and the black filled IR was successfully described by a two-component model. The short T2 component arose from the chemically crosslinked (gel) and physically entangled (heavy sol) network. The long T2 decay came from the unentangled sol and dangling network chain ends. Vulcanization decreased the molecular mobility; however, ultrasound devulcanization partially reversed this effect. Addition of processing oil in the filled IR significantly altered the dependence of T2 on the sol fraction. T2 and pulsed-gradient diffusion experiments were carried out on IR melt specimens after sonication with or without subsequent vulcanization. The lowered and broadened M-distribution produced results quantitatively related to earlier work in natural rubber.
Optimization of Composites Based on PP/Elastomer Blends and Short Pet Fibers
Authors: López-Manchado M. A. , Arroyo M. 
Published: February 2011

Abstract
The physical and mechanical properties of ternary composites based on isotactic polypropylene (iPP) and ethylene—octene copolymer blends reinforced with poly(ethylene terephthalate) (PET) fibers have been studied. In order to evaluate the effect of the matrix composition and fiber content on the final properties of the composite, an experimental design based on a Doehlert Uniform Net has been employed. The results show that PET fibers behave as a reinforcing agent for PP/ethylene—octene copolymer blends, this effect being more evident at high copolymer percentages in the blend. It is important to notice that the analyzed mechanical properties are more dependent on matrix composition than on fiber percentage. So, as PP content is increased, the blend becomes more rigid and stable, and a noticeable increase in tensile and flexural modulus and strength are observed. Moreover, dynamic mechanical measurements provide a further confirmation of the reinforcing effect of these fibers. A displacement of the glass-transition temperature ((Tg)) of the elastomeric phase to higher temperatures is observed as fiber content in the composite increased. The morphology of the composites has been also analyzed by scanning electron microscopy (SEM). Good interfacial adhesion between fibers and matrix is observed, especially when the copolymer is the continuous phase. Hence, it is possible to correlate good interaction at the fiber—matrix interface with an improvement of composite properties.
Monitoring Thermal Oxidation of Sulfur Crosslinks in SBR-Elastomers by Quantitative Analysis of Sulfur K-Edge XANES-Spectra
Authors: Modrow H. , Hormes J. , Visel F. , Zimmer R. 
Published: February 2011

Abstract
This paper presents a quantitative description of the processes occurring at the sulfur crosslinks of vulcanized rubber during thermo-oxidative aging. To extract this information in a nondestructive way, sulfur K-edge X-ray absorption near-edge structure (XANES) spectra have been analyzed quantitatively. We find that reversion takes place before the onset of oxidative processes at the sulfur bridges. Parallel to the oxidative processes, the production of cyclic sulfanes takes place. Both the relative and absolute contributions of the different reactions involving the sulfur crosslinks vary strongly with sample composition. Whereas antidegradants delay the thermo-oxidative aging without actually changing the aging resistance of the sulfur bonds, both the amount of S8/TBBS (N-tert-butylbenzothiazole-2-sulfenamide) and the presence of carbon black in the sample enhance this parameter considerably.
A Novel Biocidal Elastomer
Authors: Elrod D. B. , Figlar J. Gibb , Worley S. D. , Broughton Royall M. , Bickert J. R. , Santiago J. I. , Williams J. F. 
Published: February 2011

Abstract
Biocidal elastomeric materials have been produced by a three-step chemical process on commercial elastomers which are composed of a styrene/ethylene-butylene/styrene triblock copolymer. The commercial elastomeric material employed was Kraton®G, produced by the Shell Chemical Company in Houston, Texas. The three-step process involved a Friedel-Crafts acylation of the styrene blocks of the elastomer, followed by a hydantoin ring formation reaction, and subsequent halogenation with chlorine or bromine. Both raw and processed elastomeric materials were studied. The biocidal efficacies of the materials were demonstrated using several species of bacteria. A few applications for the technology may include prevention of disease by biocidal surgical gloves, condoms, protective clothing, food packaging, and the prevention of biofouling in elastomeric tubing.
A New Constitutive Model for the Compressibility of Elastomers at Finite Deformations
Authors: Bischoff Jeffrey E. , Arruda Ellen M. , Grosh Karl 
Published: February 2011

Abstract
Although traditional constitutive models for rubbery elastic materials are incompressible, many materials that demonstrate nonlinear elastic behavior are somewhat compressible. Clearly important in hydrostatic deformations, compressibility can also significantly affect the response of elastomers in applications for which several boundaries are rigidly fixed, such as bushings, or triaxial states of stress are realized. Compressibility is also important for convergence of finite element simulations in which a rubbery elastic constitutive law is in use. Volume changes that reflect compressibility have been observed historically in both uniaxial tension and hydrostatic compression tests; however, there appear to be no data obtained from both types of tests on the same material by which to validate a compressible hyperelastic law. In this paper, we propose a new compressible hyperelastic constitutive law for elastomers and other rubbery materials in which entropy and internal energy changes contribute to the volume change. Using data from the literature, we show that this law is capable of reproducing both the pressure—volume response of elastomers in hydrostatic compression, as well as the stress—stretch and volume change—stretch data of elastomers in uniaxial tension.
Quantum Mechanical Calculations to Assess the Antireversion Effects of Several Dienophiles
Authors: Talma A. G. , Datta R. N. , Aerts J. 
Published: February 2011

Abstract
The utilization of Quantum mechanical calculations for substituted dienophiles in the Diels—Alder reaction is very useful in assessing the antireversion effect of various dienophiles. It has been demonstrated that citraconimides provide better antireversion properties than maleimides. A useful explanation is that although maleimides are better dienophiles, they do not survive the vulcanization medium and consequently are not available during the onset of reversion. The antireversion effect of dienophiles varies with the electronic and steric nature of the substituents on the double bond of the dienophile. Calculations are made to demonstrate the effectiveness of various dienophiles in a Diels—Alder reaction. A good correlation has been obtained between the calculations and experimental results.
Initial Development of Structure—Property Relationships for Dynamically Vulcanized EPDM/IPP Elastomers
Authors: Wright Kathryn J. , Lesser Alan J. 
Published: February 2011

Abstract
The mechanical behavior and morphology of dynamically vulcanized blends of ethylene—propylene—diene monomer and isotactic polypropylene are investigated. The composition of the thermoplastic elastomers dictates their morphology, which in turn controls their mechanical behavior. Six compositions are examined under quasi-static and dynamic mechanical loading conditions. Although these elastomers are processable thermoplastics, they all exhibit a Payne effect much like traditional crosslinked materials. However, the mechanisms responsible for this behavior are different than those of crosslinked systems. The “Payne effect” response is studied and characterized over a range of compositions, and the results are discussed in light of the elastomer morphologies.
Barrier Properties of Thermoplastic Elastomer Films
Authors: Xu R. , Mead J. L. , Orroth S. A. , Stacer R. G. , Truong Q. T. 
Published: February 2011

Abstract
One application of barrier materials is chemical protective clothing. A variety of chemical protective clothing options are currently available, but many of the barrier materials combine good fluid resistance with high resistance to moisture vapor transport. This generates heat stress to the wearer. For certain applications it is desirable to find materials which are elastic, easy to process, and comfortable to use, while still having good fluid resistance. Thermoplastic elastomers (TPE) represent a developing family of materials that may provide an answer to those requirements, but have not been thoroughly investigated for this application. In this work, commercially available thermoplastic elastomers and their blends were evaluated. Film samples were prepared by either extrusion or compression molding, and their barrier properties evaluated in terms of water vapor transmission, fluid vapor transmission, and fluid absorption. Films prepared from a polyester TPE showed the highest water vapor transport. Blends of the polyester TPE with more fluid resistant TPEs offered protection with enhanced water vapor transport. These results indicate that blends of TPEs can be tailored to offer fluid/vapor protection with significant improvements in water vapor transmission. For some fluids these materials offer even better protection, with enhanced water vapor transmission, than currently available materials.
Characterization of the Large and Small Rubber Particles in Fresh Hevea Latex
Authors: Sakdapipanich Jitladda T. , Nawamawat Kanjanee , Kawahara Seiichi 
Published: February 2011

Abstract
The rubbers from small and large rubber particles were separated from the serum and cream phases of centrifuged fresh Hevea latex, respectively. The small rubber particles (SRP) consist of rubber molecules showing a unimodal molecular weight distribution (MWD), with a peak-top value falling between the two peak values of the bimodal MWD observed in rubbers from the large rubber particles (LRP). The rubbers in LRP from mature trees and SRP from seedlings are polyisoprene molecules terminated by phospholipids comprising branching points, while those in SRP from mature trees are presumed to be linear molecules containing no phospholipid terminal. The serum rubber was found to be soft and viscous rubber differing from the cream rubber containing in LRP. Thus, it can be presumed that the particle size of rubber latex is an important parameter influencing the MW, MWD and physical properties of Hevea rubber.
Modeling Step—Strain Relaxation and Cyclic Deformations of Elastomers
Authors: Johnson A. R. , Chen T. , Mead J. L. 
Published: February 2011

Abstract
Data for step—strain relaxation and cyclic compressive deformations of highly viscous short elastomer cylinders are modeled using a large strain rubber viscoelastic constitutive theory with a rate—independent friction stress term added. In the tests, both small and large amplitude cyclic compressive strains, in the range of 1% to 10%, were superimposed on steady state compressed strains, in the range of 5% to 20%, for frequencies of 1 and 10 Hz. The elastomer cylinders were conditioned prior to each test to soften them. The constants in the viscoelastic—friction constitutive theory are determined by employing a nonlinear least-squares method to fit the analytical stresses for a Maxwell model, which includes friction, to measured relaxation stresses obtained from a 20% step—strain compression test. The simulation of the relaxation data with the nonlinear model is successful at compressive strains of 5%, 10%, 15%, and 20%. Simulations of hysteresis stresses for enforced cyclic compressive strains of 20%±5% are made with the model calibrated by the relaxation data. The predicted hysteresis stresses are lower than the measured stresses.
Parameter Dependence and Prediction of Fatigue Properties of Elastomer Products
Authors: Alshuth T. , Abraham F. , Jerrams S. 
Published: February 2011

Abstract
Fatigue tests on ethylene propylene (EPDM) and styrene-butadiene (SBR) rubber reveal physical behavior that is not seen in conventional linear elastic solids. Uniaxial cyclical tests, using cylindrical dumbbell specimens, with the same minimum stress of zero (Smin=0) and varying stress amplitude (sa), predictably gave decreased fatigue life with increased stress amplitude and hence maximum stress (Smax). However, tensile uniaxial cyclic tests where Smin was increased in successive tests while alternating stress (sa) remained constant, produced longer fatigue lives for higher values of Smax.
EPDM and SBR compounds were chosen for the tests because they do not strain crystallize during deformation. Consequently, this phenomenon has no influence. The results show that Smax can not be used as criterion to predict fatigue life of elastomers. Preliminary evaluation of recorded data of stress vs. strain gave evidence that energies control the fatigue life rather than stress and strain. Experimental results on filled and unfilled rubber materials are evaluated and discussed as well as the consequences on predictions of component properties.
Methods for Measuring the Crack Length in Rubbery Pure Shear and Sent Specimens
Authors: Yang K. J. , Kang K. J. 
Published: February 2011

Abstract
A new approach for measuring crack length, which can be used for automization of fatigue test of rubber materials, is described. The crack length in the pure shear and SENT(Single Edge Notched Tension) specimens is evaluated from the variation of the peak loads under a constant cyclic displacement. For the pure shear specimen, a simple equation to give the crack length was derived from elementary consideration of the deformation pattern. The equation was applied to two constitutive models to simulate the hyperelastic behavior. It was experimentally proven that the crack length can be measured well. For the SENT specimen, an equation to give the crack length was derived from dimensional analysis. The function was assumed to be separated as the product of the deformation and geometry functions. Experiments were performed to prove the validity of the separation and to evaluate the details of the function.