bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of ultrasonic waves in activation of microcrystalline cellulose
Authors: Wang Xianling , Fang Guizhen , Hu Chunping , Du Tianchuan 
Published: May 2008

AbstractIn this work, microcrystalline cellulose (MCC) was activated with ultrasonic waves. The influences of ultrasonic treatment on the changes of supramolecular structures and morphology structure were studied by WAXS and SEM. The accessibility of the MCC was characterized by water retention value (WRV) and specific surficial area. The influence of ultrasonic treatment on the reactivity of MCC was investigated through the reaction of MCC being oxidized into 2,3‐diadehyde cellulose (DAC) by periodate sodium. The mechanism of the reactivity change of ultrasonically treated MCC was examined. The results showed that the degree of crystallinity of MCC decreased and the degree of polymerization showed little change after treatment with ultrasonic waves. The morphologial variation of the treated MCC was significant when compared with the untreated MCC, which contribute to the improvement of accessibility. The aldehyde content of DAC prepared from ultrasonically treated MCC was improved from 64.19 to 85.00%, indicating that the regioselective oxidation reactivity of MCC was significantly improved. The aldehyde content was found to first increase with time of ultrasonic treatment to a point, and then decrease as time progressed. In addition, the aldehyde content was found to increase with an increase in ultrasonic power. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Chemical grafting of metallocene‐catalyzed functional polypropylene copolymer on glass substrates through surface modification
Authors: Etcheverry Mariana , Damiani Daniel E. , Ferreira María L. , Barbosa Silvia E. , Capiati Numa J. 
Published: May 2008

AbstractThis work deals with surface modification of soda‐lime glass slides which, by itself, does not have hydroxyl groups at the surface. So, a glass surface pretreatment is needed, to create hydroxyl groups onto it, before carrying out the polypropylene (PP) grafting reaction. Different acid/base pretreatments were performed to develop an adequate concentration of superficial hydroxyl groups. Subsequently, a metallocenic polymerization (propylene‐α olefin graft reaction, catalyzed by EtInd2ZrCl2/methylaluminoxane), was carried out to provide graft‐PP chains chemically linked to the glass surface. The surface so modified can be further functionalized and tailored for different applications, including polymer composites. The pretreatment conditions that best preserved homogeneity and caused less damage to the glass surface resulted from a step of contact with dilute HF/NH4F buffer, a washing step with distilled water, and a final exposure to KOH. After the propylene copolymerization was performed, part of the graft copolymer formed remained chemically bonded to the glass slide surface. The presence of grafted PP at the surface was confirmed by SEM, FTIR, and EDAX characterization, even after the physically adsorbed polymer was excluded by a severe solvent extraction treatment. From these results, the copolymerization of a hydroxy α‐olefin, grafted on a MAO‐pretreated glass slide, is foreseen as a possible way to graft polymers onto inorganic solids. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Adjustable wettability of methyl methacrylate modified ramie fiber
Authors: Liu Zhao‐Tie , Sun Chang'an , Liu Zhong‐Wen , Lu Jian 
Published: May 2008

AbstractThe surface hydrophobicity/hydrophilicity of ramie fiber was regulated through the atom transfer radical polymerization of methyl methacrylate from initiators immobilized on the fiber. The optimal reaction conditions for preparing the macroinitiated ramie fiber were determined to be a temperature of 60°C and a reaction time of 24 h. The grafted copolymers were characterized by Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, energy‐dispersive analysis of X‐rays, gel permeation chromatography, and thermogravimetric analysis. The results indicate that poly (methyl methacrylate) was covalently bonded onto the surface of the ramie fiber, and the polymerization of methyl methacrylate was a living/controlled process under the investigated conditions. The results of the contact angle measurements indicate that the wettability of the ramie fiber could be widely regulated by control of the grafted ratios of poly(methyl methacrylate) from 26 to 33 wt %. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Removal of basic dyes from aqueous solutions with sulfonated phenol–formaldehyde resin
Authors: İyim Tülin Banu , Acar Işıl , Özgümüş Saadet 
Published: May 2008

AbstractIn this study, we aimed to investigate the removal of basic dyes, including Safranin T (ST), Nile Blue A (NBA), and Brilliant Cresyl Blue (BCB), from aqueous solution with a sulfonated phenol–formaldehyde resin. This sulfonated resin was characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. The adsorption properties of this resin were investigated under different adsorption conditions with different initial dye concentrations, contact times, and pH values. The adsorption equilibrium data were analyzed with Langmuir and Freundlich models. The adsorption behaviors of ST, NBA, and BCB onto the sulfonated resol‐type phenol–formaldehyde resin were better described by the Freundlich model. The adsorption capacities of the sulfonated resol resin for ST, NBA, and BCB decreased in the following order: NBA > BCB > ST. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Introducing two simple models for predicting fiber‐reinforced asphalt concrete behavior during longitudinal loads
Authors: Hejazi Sayyed Mahdi , Abtahi Sayyed Mahdi , Sheikhzadeh Mohammad , Semnani Dariush 
Published: May 2008

AbstractScientists and engineers are constantly trying to improve the performance of asphalt pavements. Modification of the asphalt binder is one approach taken to improve pavement performance. The idea of using fibers to improve the behavior of materials is an old suggestion, so different researchers reported the results of adding a large variety of fibers to asphalt concrete (AC) as fiber‐reinforced asphalt concrete (FRAC). However, there are few comments about the mechanism of reinforcement and fiber performance in the inner structure of AC and/or exposing some models to predict fiber recital as a modifier in FRAC. So this article is going to introduce two simple models for predicting FRAC behavior during longitudinal loads. The former is called “Slippage Theory” and the latter is “Equal Cross‐Section.” Finally, four types of fibers (glass, nylon 6.6, polypropylene, and polyester) were used in AC to evaluate the two theories. “Marshall Test,” as stability and flow outcomes, and “Specific Gravity” were carried out on specimens in the next stages followed by an artificial neural network (ANN), which was developed in the system to recognize important fiber parameters effective in the FRAC specifications. In the end, the two theories predicted each fiber performance in FRAC as well as ANN. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis and characterization of the new unsaturated epoxyoligoester suitable for further modification
Authors: Worzakowska Marta 
Published: May 2008

AbstractIn this article, the synthesis and characterization of the new unsaturated epoxyoligoester suitable for further modification have been presented. The new unsaturated epoxyoligoester was prepared by the chemical modification of the structure of the unsaturated oligoester obtained in polycondensation process of cyclohex‐4‐ene‐1,2‐dicarboxylic anhydride, maleic anhydride, and ethylene glycol. The chemical modification of the structure of initial oligoester by 38–40% peracetic acid in mild conditions allowed to introduce the oxirane groups into the oligoester backbone. The structure of the samples before and after epoxidation was characterized by FTIR, 1H NMR, DSC, and elemental analyses. The FTIR and 1H NMR analyses confirmed that the oxidation reaction took place through the double bonds in cyclohexenyl rings, whereas the double bonds in the unsaturated chain remained unaltered. Moreover, the epoxidation reaction was performed at 20 and 40°C for 1–6 h to define the optimum temperature and time conditions of this process. The optimum temperature and time conditions were 40°C and 2.5 h, respectively. In this conditions, the maximum conversion of the double bonds (98.3%) and minimal epoxide degradation were observed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Evaluation and prediction of the effects of melt‐processing conditions on the degree of mixing in alumina/poly(ethylene terephthalate) nanocomposites
Authors: Kim Dongsik , Lee Jun S. , Barry Carol F. , Mead Joey L. 
Published: May 2008

AbstractAlumina/poly(ethylene terephthalate) nanocomposites were prepared by melt compounding with a twin‐screw extruder. The melt temperature, screw rotation speed, and feed rate were selected as important processing parameters, and their effects on the degree of mixing were studied with full‐factorial, two‐level experimental design. To quantitatively assess the effects of the processing parameters, the degree of mixing of the nanocomposites was evaluated by the skewness of the quadrat method based on the number of particles in transmission electron microscopy images. The screw speed was found to be the most important processing parameter controlling the degree of mixing under the conditions in this investigation. The specific energy input (SEI), related to the shear intensity, was found to correlate closely to the degree of mixing. The degree of mixing improved with increased SEI up to a limiting value, termed the critical SEI, indicating that there may be a critical value required for the optimum dispersion of a given system. A modeling approach was proposed to determine the critical SEI needed for complete mixing. Initial results showed that the critical SEI predicted by this model was within a factor of 3.5 of that obtained experimentally, demonstrating the utility of this approach for the dispersion of nanofillers. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Ethylene/α‐olefin copolymerization using diphenylcyclopentadienyl‐phenoxytitanium dichloride/Al(iBu)3/[Ph3C][B(C6F5)4] catalyst systems
Authors: Li Hongchun , Li Jincai , Zhang Yuetao , Mu Ying 
Published: May 2008

AbstractCopolymerization of ethylene with 1‐octene and 1‐octadecene using constrained geometry catalysts 2‐(3,4‐diphenylcyclopentadienyl)‐4,6‐di‐tert‐butylphenoxytitanium dichloride (1), 2‐(3,4‐diphenylcyclopentadienyl)‐6‐tert‐butylphenoxytitanium dichloride (2), 2‐(3,4‐diphenylcyclopentadienyl)‐6‐methylphenoxytitanium dichloride (3), and 2‐(3,4‐diphenylcyclopentadienyl)‐6‐phenylphenoxytitanium dichloride (4) was studied in the presence of Al(iBu)3 and [Ph3C][B(C6F5)4](TIBA/B). The effect of the catalyst structure, comonomer, and reaction conditions on the catalytic activity, comonomer incorporation, and molecular weight of the produced copolymers was also examined. The 1/TIBA/B catalyst system exhibits high catalytic activity and produces high molecular weight copolymers. The melting temperature and the degree of crystallinity of the copolymers show a decrease with the increase in the comonomer incorporation. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Neuronal Fiber Composition of the Corpus Callosum Within Some Odontocetes
Authors: Keogh Mandy J. , Ridgway Sam H. 
Published: May 2008

AbstractOdontocetes (toothed whales) evolved from terrestrial mammals approximately 55 million years ago and have since remained on a unique evolutionary trajectory. This study used formalin‐fixed tissue and light microscopy to quantify the size and number of fibers along the corpus callosum of the bottlenose dolphin (n = 8). Two other species, the Amazon River dolphin (n = 1) and the killer whale (n = 1), were included for comparison. A large amount of variation in the shape and area of the corpus callosum was observed. The odontocete corpus callosum is a heterogeneous structure with variation in fiber size and density along the length of the corpus callosum in all specimens examined. Using the species with the largest sample size, the bottlenose dolphin, comparisons by sex and age (sexually mature verses immature) were made for the area of the corpus callosum, five subregions, and fiber densities. Although no sex differences were detected, age appeared to affect the size, shape, and fiber composition of the bottlenose dolphin corpus callosum. Anat Rec, 291:781‐789, 2008. © 2008 Wiley‐Liss, Inc.
Synthesis of New 3‐Substituted‐5‐(2‐hydroxyethyl)‐3,4,5,6‐tetrahydro‐2H‐l,3,5‐thiadiazine‐2‐thione Derivatives with Potential Antimicrobial Activity
Authors: Hussein Mostafa A. , Hashem Mohammed 
Published: May 2008

AbstractThe purpose of this study is based upon design and synthesis of a new series of flexible molecules of 3,4,5,6‐tetrahydro‐2H‐1,3,5‐thiadiazine‐2‐thione (THTT) derivatives depending upon incorporation of 2‐aminoethanol as a part of the polar moiety in this nucleus. Thirteen derivatives of 3‐substituted‐5‐(2‐hydroxyethyl)‐3,4,5,6‐tetrahydro‐2H‐1,3,5‐thiadiazine‐2‐thione were synthesized by reaction of the appropriate alkyl, cycloalkyl, aralkyl amine, or glycine with carbon disulphide, formaldehyde, and 2‐aminoethanol. The structures of the target compounds were elucidated using spectral methods as well as elemental analyses. A mass‐spectrometry study was carried out on representatives of the synthesized derivatives. The title compounds were tested for their antibacterial activity in vitro against some gram positive and gram negative bacteria. The in‐vitro antifungal activity was tested against dermatophytic, saprophytic, phytopathogenic, and antagonistic fungi. In most cases, the newly synthesized compounds 4–16 exhibited a considerable inhibitory effect on the growth of some of the tested organisms in comparison to that of ampicillin or muconazole as reference drugs. Moreover, the results indicated that the polar hydroxyethyl group at the N5‐ and the lipophilic one at the N3‐positions are essential for the antimicrobial activity of the tested compounds.
Anatomy: Spotlight on Africa
Authors: Kramer Beverley , Pather Nalini , Ihunwo Amadi O. 
Published: May 2008

AbstractAnatomy departments across Africa were surveyed regarding the type of curriculum and method of delivery of their medical courses. While the response rate was low, African anatomy departments appear to be in line with the rest of the world in that many have introduced problem based learning, have hours that are within the range of western medical schools and appear to be well resourced. Human body dissection is a constant and strong aspect of the majority of the courses surveyed. The staff to student ratio appears to be relatively high in Africa, but in many of the responding African institutions, there appears to be little difficulty in attracting suitable faculty (including those who are medically qualified) to teach anatomy. Retaining this faculty, in some cases, may be difficult because of a global demand for anatomy educators. Anat Sci Ed 1:111–118, 2008. © 2008 American Association of Anatomists.
Intradisciplinary differences in database coverage and the consequences for bibliometric research
Authors: Frandsen Tove Faber , Nicolaisen Jeppe 
Published: May 2008

AbstractBibliographic databases (including databases based on open access) are routinely used for bibliometric research. The value of a specific database depends to a large extent on the coverage of the discipline(s) under study. A number of studies have determined the coverage of databases in specific disciplines focusing on interdisciplinary differences; however, little is known about the potential existence of intradisciplinary differences in database coverage. Focusing on intradisciplinary differences, the article documents large database‐coverage differences within two disciplines (economics and psychology). The point extends to include both the uneven coverage of specialties and research traditions. The implications for bibliometric research are discussed, and precautions which need to be taken are outlined.
Evaluating a dual‐process model of risk: affect and cognition as determinants of risky choice
Authors: van Gelder Jean‐Louis , de Vries Reinout E. , van der Pligt Joop 
Published: May 2008

AbstractIn three studies we addressed the impact of perceived risk and negative affect on risky choice. In Study 1, we tested a model that included both perceived risk and negative affect as predictors of risky choice. Study 2 and Study 3 replicated these findings and examined the impact of affective versus cognitive processing modes. In all the three studies, both perceived risk and negative affect were shown to be significant predictors of risky choice. Furthermore, Study 2 and Study 3 showed that an affective processing mode strengthened the relation between negative affect and risky choice and that a cognitive processing mode strengthened the relation between perceived risk and risky choice. Together, these findings show support for the idea of a dual‐process model of risky choice. Copyright © 2008 John Wiley & Sons, Ltd.
Morphometric analysis of metacarpophalangeal and proximal interphalangeal palmar plates
Authors: Kömürcü Mahmut , Kirici Yalçin , Korkmaz Cem , Alemdaroğlu Kadir Bahadir , Sanısoğlu Yavuz , Başbozkurt Mustafa 
Published: May 2008

AbstractPalmar plates are being used as a source of graft in radial or ulnar collateral ligament reconstruction, pulley reconstruction, and volar plate arthroplasty. The purpose of this study is to determine morphometric and major histological differences of palmar plates in metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints among fingers, and supply sufficient data which would be useful in reconstruction procedures. Ninety‐six MCP and 96 PIP palmar plates of 12 well‐preserved formalin‐fixed cadavers were measured focusing on their length, width, central thickness, and lateral thickness and statistically analyzed using ANOVA. Randomized three male and three female cadavers' specimens were examined histologically after staining with Masson's trichrome. For central thickness of the PIP joint level, there was significant difference among fingers, caused by the middle and little fingers. For lateral thickness of the PIP joint level, there was significant difference which was originated from little fingers. MCP palmar plates were significantly thicker than PIP joint levels for most of the fingers. There were thicker and denser collagen bands in MCP than PIP palmar plates. The relation of size‐related parameters was not close with the thickness parameters. The predicted sizes and thicknesses of palmar plates vary according to fingers. The data collected for each finger in this study should be used as a guide in reconstructive procedures that use palmar plates as source of graft. Clin. Anat. 21:433–438, 2008. © 2008 Wiley‐Liss, Inc.
Inter‐professional working in child protection with families with long‐term and complex needs
Authors: Devaney John 
Published: May 2008

AbstractWithin the United Kingdom there is growing awareness of the need to identify and support the small number of children who are living in families experiencing multiple problems. Research indicates that adverse experiences in childhood can result in poor outcomes in adulthood in terms of lack of employment, poorer physical and mental health and increases in social problems experienced. It is acknowledged that most of these children are known to child welfare professionals and that some are referred to social services, subsequently entering the child protection system. This paper reports research conducted with 28 experienced child welfare professionals. It explores their views about families known to the child protection system with long‐term and complex needs in relation to the characteristics of children and their families; the process of intervention with families; and the effects of organisational arrangements on practice. The research indicates that these families are characterised by the range and depth of the problems experienced by the adults, such as domestic violence, mental health difficulties and substance misuse problems, and the need for professionals to have good inter‐personal skills and access to specialist therapeutic services if families are to be supported to address their problems. Copyright © 2008 John Wiley & Sons, Ltd.
Ecdysteroids from Vitex Species: Distribution and Compilation of Their 13C‐NMR Spectral Data
Authors: Sena Filho José G. , Duringer Jennifer , Maia Gabriela L. A. , Tavares Josean F. , Xavier Haroudo S. , Sobral da Silva Marcelo , da‐Cunha Emídio V. L. , Barbosa‐Filho José M. 
Published: May 2008

AbstractIridoids and ecdysteroids are found in some genera of the family Verbenaceae. In such cases, they are used as chemotaxonomic markers for the difficult task of taxonomic identification by using morphological characteristics of plants belonging to this family. The present work describes the distribution of ecdysteroids in plants from the genus Vitex from a review of previous work on seventeen Vitex species. In addition, 13C‐NMR data of the main ecdysteroids found in this genus are described. This study attempted to summarize previous research on ecdysteroids distribution in Vitex species with the addition of 13C‐NMR analysis to further refine the characterization of these compounds in the Verbenaceae family.
Chemical Constituents of Stereum subtomentosum and Two Other Birch‐Associated Basidiomycetes: An Interspecies Comparative Study
Authors: Hybelbauerová Simona , Sejbal Jan , Dračínský Martin , Hahnová Alice , Koutek Bohumír 
Published: May 2008

AbstractMetabolites of the wood‐rotting fungus Stereum subtomentosum Pouzar (Basidiomycetes, order Russulales, family Stereaceae) occuring on birch (Betula pendula Roth) trees were phytochemically investigated for the first time. Three main metabolite chemotypes present in MeOH extracts of the fruit bodies, viz. steroids, fatty acids, and water‐soluble sugars, were fractionated, isolated, and identified by 1D/2D NMR‐spectroscopic analyses, NMR data comparisons, and chemical correlations combined with GC/MS experiments. Thirteen compounds including two 5α,8α‐epidioxy steroids, α,α′‐trehalose, D‐arabinitol, D‐mannitol, and saturated/unsaturated fatty acids, were identified. Differences among S. subtomentosum and two other birch‐associated fungal species, Trametes versicolor (L.: Fr.) Pilát, and Piptoporus betulinus (Bull.: Fr.) P. Karst (Basidiomycetes, order Polyporales, family Polyporaceae) were evaluated as regards the richness and abundance relationships in metabolite profiling.
Two New Megastigmane Glycosides, Physanosides A and B, from Physalis alkekengi L. var. franchetii, and Their Effect on NO Release in Macrophages
Authors: Qiu Li , Zhao Feng , Liu Hongwei , Chen Lixia , Jiang Zhihu , Liu Hongxia , Wang Naili , Yao Xinsheng , Qiu Feng 
Published: May 2008

AbstractTwo new megastigmane glycosides, physanosides A and B (1 and 2, resp.), were isolated from Physalis alkekengi L. var. franchetii, together with four known compounds (6S,9R)‐roseoside (3), (6S,9S)‐roseoside (4), (6R,9S)‐3‐oxo‐α‐ionol β‐D‐glucopyranoside (5), and citroside A (6). Their structures were elucidated on the basis of physicochemical evidence, in‐depth NMR spectroscopic analysis, high‐resolution mass spectrometry, and CD spectroscopy, and their inhibitory effect on NO production was also examined. Compounds 2 and 3 exhibited strong inhibition on lipopolysaccharide‐induced NO release by macrophages with IC50 values of 9.93 and 7.31 μM, respectively.