bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the radiative properties of cirrus cloud at solar and thermal wavelengths: A test of model consistency using high‐resolution airborne radiance measurements
Authors: Baran A. J. , Francis P. N. 
Published: May 2004

AbstractTwo models describing the single‐scattering properties of cirrus cloud are tested for physical consistency at solar and thermal wavelengths using airborne high‐resolution radiance data. The data were obtained from a case of semi‐transparent cirrus cloud, which occurred north of Scotland during October 2000. The single‐scattering models tested are randomly oriented hexagonal ice columns and randomly oriented ice aggregates. High‐spectral resolution radiances were measured from above the cirrus at a number of wavelengths between 0.3 and 16.7 µm, thereby covering a large range of ice crystal size parameter space and complex refractive index. It is shown that consistency between retrieved optical thickness and ice crystal effective radius at both solar and infrared wavelengths could only be achieved if the ice aggregate model was assumed. Moreover, differences between the ice aggregate model and spectrally resolved brightness temperature measurements were generally well within ±1 K between the wavelengths of 3.3 and 16.0 µm in the clean atmospheric window regions. The paper shows that it is important to have simultaneous radiance measurements from both the solar and thermal spectral regions so that ice crystal scattering models and cirrus retrievals can be rigorously tested. © Crown copyright 2004.
Quasi‐periodic bora gusts related to the structure of the troposphere
Authors: Beluši'c Danijel , Pasarić Miroslava , Orlić Mirko 
Published: May 2004

AbstractThis study provides a new insight into the behaviour of the bora wind gusts. Wind speed and direction measured with a 1 s sampling interval between 1 December 2001 and 31 January 2002 at Senj (east Adriatic) provided a sufficiently large database for a study of the gusts behaviour. The performed spectral analysis confirmed the occurrence of pulsations in the bora flow. Moreover, a new type of dynamics, involving the onset, cessation and reappearance of the pulsations within a single episode, has been observed in several cases. Suggested mechanisms responsible for generating these phenomena have been determined from comparisons of surface wind data with the upstream tropospheric thermodynamical structure derived from Zagreb radiosonde data. In particular, it has been shown that the appearance of an upper‐tropospheric jet stream results in cessation of the pulsations, and the decrease in the jet stream supports quasi‐periodic gust behaviour. As the pulsations are generated by wave breaking, the jet stream appearance has been related to the disappearance of the wave‐breaking region in the lee of the mountain, which is in accordance with previous studies of downslope windstorms. Copyright © 2004 Royal Meteorological Society.
Polar low le Cygne: Satellite observations and numerical simulations
Authors: Claud Chantal , Heinemann Guenther , Raustein Elmer , Mcmurdie Lynn 
Published: May 2004

AbstractA polar low (PL) which occurred in October 1993 over the Norwegian Sea is investigated from an observational and a numerical point of view. This PL has several unique features: it developed early in the season, it lasted for about 3 days, and its trajectory was such that it passed over weather stations so that ‘conventional’ observations of the low are available. The conditions of the formation, development and decay of the PL are investigated using a double approach: satellite data from several instruments are used together to document the mesoscale structure of the low, and two versions of a limited‐area model are run to investigate the dynamics of the low. Numerical model fields are compared to quantities derived from TIROS‐N Operational Vertical Sounder, the Special Sensor Microwave/Imager, and satellite radar altimeter data. In spite of a better spatial resolution of the models, humidity and surface wind speeds are less organized in the simulations than in satellite retrievals. The number of vertical levels, especially for the lowest layers of the atmosphere, appears to be an essential component for a good simulation of the trajectory of the low. There is, however, good overall agreement between modelled and satellite‐derived fields, and the good quality of the simulations allows inferences to be made regarding the essential physical and dynamical processes taking place during the formation and development of the PL. We find that the PL was the result of favourable flow conditions at the surface in the form of a shallow arctic front established south of the ice edge, together with an upper‐level potential‐vorticity anomaly setting the stage for a positive interaction. Later on, the strong surface sensible‐ and latent‐heat fluxes contributed to the extensive vertical development. This study demonstrates the usefulness of the approach adopted here, which relies not only on simulations but also on observations to get a very complete description of such disturbances. Copyright © 2004 Royal Meteorological Society.
Dieting and working memory: Preoccupying cognitions and the role of the articulatory control process
Authors: Shaw Jacqueline , Tiggemann Marika 
Published: May 2004

Objectives: The study aimed to extend previous research that has demonstrated impaired cognitive function among dieters, by teasing out precisely which components of the phonological loop subsystem of working memory are affected by dieting.Method: Participants were 92 female undergraduate students divided into three groups; current dieters (n = 19), past dieters (n = 29) and never dieters (n = 44). They completed cognitive performance tasks designed to preferentially load on the phonological store and articulatory control process components of the phonological loop, as well as self‐report measures.Results: Current dieting to lose weight had no effect on the phonological store, as evidenced by the lack of effect on the phonological similarity effect. Dieting did, however, impede the articulatory control process, as evidenced by substantial reduction in the world length effect. This effect was partially mediated by preoccupying cognitions concerning food, weight and body shape. Further, the results mirrored those found with non‐dieters under conditions of articulatory suppression.Conclusions: The results clearly identify the articulatory control process as the site of the cognitive impairment suffered by dieters, and thereby offer very strong support to the preoccupying cognitions concerning food, weight and body shape that accompany dieting behaviour as the underlying mechanism.
Individual differences in the temporal variability of medically unexplained symptom reporting
Authors: Ferguson Eamonn , Cassaday Helen J. , Erskind James , Delahaye Gemma 
Published: May 2004

Theory: Non‐specific or medically unexplained symptoms account for up to 35% of outpatient referrals. In contrast to the literature on affect, little is known about how people frame daily symptoms and how these patterns are influenced by individual differences.Method: Three fixed occasion diary studies over an 8‐day period (one on ill veterans of the Gulf War and two on healthy undergraduates) and a single cross‐sectional survey (on ill Gulf War veterans) were conducted. The severity and frequency of daily symptoms were assessed in all daily diary samples, together with the Big 5 personality domains in one of the undergraduate samples and in the survey of veterans. The data were analysed using auto‐correlations and hierarchical multivariate linear modelling.Results: In all the chronically ill and healthy samples, the data suggested potential cyclical patterns for symptom severity reporting. With regard to the frequency of symptom reporting, the veterans showed a pattern of constant symptom reporting. Finally, the relationship between the reported severity of symptoms was attenuated by intellect and surgency.Discussion: There is evidence that daily experiences of symptom severity are framed relative to each other and this relationship is influenced by personality. The practical implications of these findings are discussed.
Stages of motivational readiness for physical activity: A comparison of different algorithms of classification
Authors: Godin Gaston , Lambert Léo‐Daniel , Owen Neville , Nolin Bertrand , Prud'homme Denis 
Published: May 2004

Objective: The aim of this study was to compare two approaches to classify individuals into stages of motivational readiness for physical activity and test which one was better explained by attitude and perceived behavioural control, as defined by Ajzen (1991).Design: A survey of 20430 respondents from a population‐based sample.Methods: The relevant variables were assessed in a self‐administered questionnaire. The cluster approach consisted of combining both intention and behaviour in order to determine clusters of individuals; such clusters correspond to different stages of motivational readiness. The stage of change (SC) approach consisted of grouping the same individuals by using the SC variable of the Transtheoretical Model (TTM).Results: The SC and cluster‐solution approaches were replicated across four subsamples of the total number of respondents. Attitude and perceived behavioural control were more strongly associated with stage membership derived from four‐cluster solution than with stage membership in the five categories assessed by the SC method.Conclusion: Stage of motivational readiness for physical activity, and possibly for other health‐related behaviours, may usefully be characterized when both recent past behaviour and intention in the near future are simultaneously and explicitly taken into consideration.
Geographic distribution of environmental factors influencing human skin coloration
Authors: Chaplin George 
Published: May 2004

AbstractSkin coloration in indigenous peoples is strongly related to levels of ultraviolet radiation (UVR). In this study, the relationships of skin reflectance to seasonal UVR levels and other environmental variables were investigated, with the aim of determining which variables contributed most significantly to skin reflectance. The UVR data recorded by satellite were combined with environmental variables and data on human skin reflectance in a geographic information system (GIS). These were then analyzed visually and statistically through exploratory data analysis, correlation analysis, principal components analysis, least‐squares regression analysis, and nonlinear techniques. The main finding of this study was that the evolution of skin reflectance could be almost fully modeled as a linear effect of UVR in the autumn alone. This linear model needs only minor modification, by the introduction of terms for the maximum amount of UVR, and for summer precipitation and winter precipitation, to account for almost all the variation in skin reflectance. A further significant finding was that the effect of summer UVR seems to reach a threshold beyond which further adaptation is difficult. Am J Phys Anthropol, 2004. © 2004 Wiley‐Liss, Inc.
Paleopathological find of a sacral neurilemmoma from ancient Egypt
Authors: Strouhal Eugen , Němečková Alena 
Published: May 2004

AbstractA large, smooth‐walled cavity molded from the pressure of a relatively hard, globular, and lobulated tissue mass was found inside the sacrum of the mature female, Imakhetkherresnet. She was the sister of the lector‐priest Iufaa, whose unmolested tomb dates to the late 26th Dynasty (prior to 625 BC). The origin of the lesion could be determined unambiguously by macroscopic, radiographic, and histological analysis. It was caused by a neurilemmoma (schwannoma, neurinoma), a benign tumor originating in a nerve sheath. This is the first description in the paleopathological literature of this kind of tumor occurring in the sacrum. Am J Phys Anthropol, 2004. © 2004 Wiley‐Liss, Inc.
Polyimide–silica hybrid films made from polyamic acids containing phenolic hydroxyl groups
Authors: Huang Yi , Qin Jiaqiang , Gu Yi 
Published: May 2004

AbstractA diamine and polyamic acid containing phenolic hydroxyl group was synthesized. A series of polyimide/silica hybrid films with strong interacton between organic and inorgamic components was prepared via sol–gel reaction. The morphology of the hybrid films was investigated by scanning electron microscopy and atomic force microscopy. The thermal stability and mechanical properties of the films were detected. The results indicated that the introduction of phenolic hydroxyl groups remarkably attributed to the improvement of tensile strength. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1198–1202, 2004
Film studies of certain new aromatic–aliphatic polyamides
Authors: Thayumanaswamy S. M. , Rajendran V. 
Published: May 2004

AbstractTwo new aromatic–aliphatic polyamides containing azo linkage in the main chain based on 2,2′‐dimethyl‐4,4′‐diaminoazobenzene and adipic/2‐chloro‐5‐methyl‐1,2‐dioic acid (α‐chloro‐δ‐methyl adipic acid) were synthesized and analyzed by thermogravimetry and films were cast. Also three polymers obtained from condensation of 4,4′‐azodibenzoic acid/adipic acid and 2,2′‐bis [4‐(p‐amino phenoxy) phenyl] propane/4,4′‐diaminoazobenzene were studied in terms of mechanical and morphological properties. Film studies were carried out interms of tensile property, scanning electron microscope, dielectric, microwave, and X‐ray diffraction pattern. Thermal studies have been done using thermogravimetric analysis, differential thermal analysis, and pyrolysis‐mass spectral data. The results were correlated with structure and orientation of the molecules. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1305–1316, 2004
Pulsed‐plasma‐polymerized aniline thin films
Authors: Tamirisa Prabhakar A. , Liddell Knona C. , Pedrow Patrick D. , Osman Mohamed A. 
Published: May 2004

AbstractAn inductively coupled pulsed‐plasma reactor was used to synthesize polyaniline thin films on several substrates positioned at various distances from the center of the radio frequency (RF) coil. The samples were characterized with Fourier transform infrared (FTIR), cyclic voltammetry, and microscopic techniques. Impedance spectroscopy was used to determine the electrical characteristics of three‐layer structures with polyaniline as the middle layer between top and bottom metal electrodes. FTIR results indicated that the chemical composition and structure of the films were very dependent on the substrate's position with respect to the RF coil, there being considerably less aromatic character closer to the coil. The electrochemical behavior of the films in acidic electrolytes was similar to that of small‐molecule aniline oxidation products; the number of peaks in the cyclic voltammograms varied with the substrate. Scanning electron microscopy indicated that as the films became thicker, they developed nodules atop a somewhat smoother underlayer. Results from transmission electron microscopy and optical birefringence suggested that the films were not completely homogeneous. The impedance measurements were consistent with relatively rough films possibly containing pinholes. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93:1317–1325, 2004
Application of crosslinked chitosan in the analysis of butyl tin speciation
Authors: Wang M. L. , Qian S. H. , Mo S. B. , Huang G. Q. , Wang H. Y. 
Published: May 2004

AbstractA new method for the separation and preconcentration of butyl tin speciation with crosslinked chitosan (CCTS) and for its determination by hydride generation atomic absorption spectrometry was developed. At pHs 6.8, 4.4, and 3.0, monobutyl tin (MBT), dibutyl tin (DBT), and tributyl tin (TBT), respectively, were separated and preconcentrated with CCTS, eluted quantitatively with 10 mL of 1 mol L−1 HCl, and determined. The method was applied to the discrimination and determination of MBT, DBT, and TBT in water and sediment samples. The detection limits of TBT, DBT, and MBT were 21.2, 25.5, and 28.5 ng L−1, respectively. The analytical recoveries of MBT, DBT, and TBT added to the samples were 91–95% for water samples and 82–90% for sediment samples. The results were satisfactory. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1326–1328, 2004
Nonisothermal crystallization, melting behavior, and morphology of polypropylene/metallocene‐catalyzed polyethylene blends
Authors: Gao Jungang , Wang Dong , Yu Maoshang , Yao Zihua 
Published: May 2004

AbstractThe nonisothermal crystallization, melting behavior, and morphology of blends of polypropylene (PP) and a metallocene‐catalyzed polyethylene (mPE) elastomer were studied with differential scanning calorimetry, scanning electron microscopy, polarized optical microscopy, and X‐ray diffraction. The results showed that PP and mPE were partially miscible and could form some cocrystallization, although the extent was very small. A modified Avrami analysis and the Mo method were used to analyze the nonisothermal crystallization kinetics of the blends. The values of the Avrami exponent indicated that the crystallization nucleation of the blends was homogeneous, the growth of the spherulites was three‐dimensional, and the crystallization mechanism of PP was not affected by mPE. The crystallization activation energy was estimated with the Kissinger method. Interesting results were obtained with the modified Avrami analysis and Mo and Kissinger methods, and the conclusions were in good agreement. The addition of less mPE increased the overall crystallization rate of PP. The relationship between the composition and morphology of the blends was examined. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1203–1210, 2004
Adhesion property of sulfonated poly(arylene ether sulfone)s
Authors: Choi I. J. , Ahn C. J. , Yoon T. H. 
Published: May 2004

AbstractSulfonated poly(arylene ether sulfone)s (S‐PESs) were synthesized from sulfonated 4,4′‐dichlorodiphenylsulfone (S‐DCDPS), 4,4′‐dichlorodiphenylsulfone (DCDPS), and 4,4′‐biphenol through variations in the molar ratio of S‐DCDPS to DCDPS from 10/90 to 40/60. The S‐PES sodium form was characterized with Fourier transform infrared, 1H‐NMR, thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis, and the intrinsic viscosity and solubility were also evaluated. The sodium form was then subjected to acidification by immersion in 1.5M HCl for 24 h at room temperature, which was followed by washing with deionized water. The S‐PES adhesive properties were measured with single laboratory shear samples with aluminum alloys, and the failure mode was investigated. The synthesized S‐PESs exhibited increased glass‐transition temperatures with increased S‐DCDPS/DCDPS ratios; their acid forms provided much lower glass‐transition temperatures than their sodium forms. In addition, the S‐PES sodium form exhibited a high intrinsic viscosity, which indicated a high molecular weight. The S‐PES acid form exhibited an adhesion strength similar to that of the sodium form, and the single‐lap‐shear strength increased with 10% S‐PES and then decreased with 20, 30, and 40% S‐PES. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1211–1218, 2004
Continuous ultrasonic devulcanization of unfilled butadiene rubber
Authors: Oh Jeong Seok , Isayev A. I. 
Published: May 2004

AbstractThe devulcanization of sulfur‐cured unfilled butadiene rubber (BR) with a grooved‐barrel ultrasonic reactor under various processing conditions was carried out. The experiments indicated that BR had a narrow devulcanization window. Outside this window, significant degradation or no devulcanization occurred. Gel permeation chromatography (GPC) measurements were carried out with the sol part of virgin and devulcanized samples to study the breakdown of the polymeric chains. The GPC data showed a significant molecular weight reduction and a broadening of the molecular weight distribution upon devulcanization, indicating that the devulcanization and degradation of BR occurred simultaneously. The rheological properties showed that devulcanized BR was more elastic than the virgin gum. The vulcanizates of the blends of virgin and devulcanized BR showed a considerable enhancement of the mechanical properties. The thermal behaviors of the virgin and devulcanized BR were found to be different. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1166–1174, 2004
Effects of ozone and chlorine dioxide on the chemical properties of cellulose fibers
Authors: Lemeune S. , Jameel H. , Chang H.‐M. , Kadla J. F. 
Published: May 2004

AbstractThe effects of ozone and chlorine dioxide on the structure of hardwood cellulose fibers were studied by chemical methods. Chlorine dioxide had very little effect on the cellulose degree of polymerization (DPv), although 40–50% of the chlorine dioxide charged was consumed. By contrast, ozonation of the cellulosic fibers resulted in a substantial reduction in the cellulose DPv. Increasing the ozone charge increased the extent of cellulose degradation. At an ozone charge of approximately 3 wt % (20 mol equiv/100 g of fiber), a 40% reduction in DPv, as measured by cupriethylenediamine viscosity, was observed. A comparison of the cellulose DPv values obtained for ozonated cellulose fibers reduced with sodium borohydride before the viscosity measurements increased confirmed that the primary reaction of ozone with the cellulose fibers was glycosidic bond cleavage, with only a small amount of cellulose oxidation taking place. A functional group analysis of the ozonated cellulose fibers revealed a slight increase in the amount of carbonyl groups introduced into the fibers. In addition, carbon dioxide was detected, which combined with the lack of change in the carboxyl group content, indicated that the oxidation mechanism likely occurred in a three‐step process: formation of the carbonyl groups, followed by oxidation to carboxyl groups, and finally, decarboxylation resulting in glycosidic bond cleavage. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1219–1223, 2004
Effect of titanate coupling agent on the mechanical properties of clay‐filled polybutadiene rubber
Authors: Alkadasi Nabil A. N. , Kapadi U. R. , Hundiwale D. G. 
Published: May 2004

AbstractClays belong to an economic class of fillers, which are used extensively in rubbers and plastics. Being nonreinforcing in nature, there are limitations upon its use. If the properties of filler are modified, it will get a higher value as a filler. To achieve this modification of surface properties is one of the avenues. In the present work, the effect of treatment of the coupling agent on clay has been studied, with polybutadiene as a matrix. Composites were made with a varying proportion of untreated and treated clay. A two‐roll mill was used for dispersing the filler in the rubber, and a compression‐molding technique was used to cure the compounded in sheet forms. Tensile properties were measured on a computerized UTM using the ASTM procedure. Comparison of properties of composites filled with treated and untreated clay established that treatment of clay imparts better reinforcing properties. The properties under consideration were tensile strength, modulus at 100 and 400%, Young's modulus, hardness, etc. Tensile strength was improved by 52%, while modulus at 400% was improved by 150%. Similarly Young's modulus also was improved by 27%. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1299–1304, 2004