bluuebunny/crossref_metadata_2025_split huggingface dataset:
Blends of high density polyethylene with branched poly(styrene‐co‐dodecyl acrylate): Rheological, mechanical, and thermal properties
Authors: Qiang Ren , Fanghong Gong , Dongliang Zhang , Xiaoxiao Shi , Jianbo Fang , Bibiao Jiang 
Published: April 2008

AbstractBranched poly(styrene‐co‐dodecyl acrylate) (BPSDA) was prepared by the atom transfer radical copolymerization of styrene with dodecyl acrylate using p‐cholomethyl styrene as initiator‐monomer (inimer) and CuCl/Bpy (2,2′‐bipyridine) complex as catalyst. The remarkable discrepancies between the molecular weight determined by gel permeation chmotagraphy and multiangel laser light scattering reveals the highly branched structure of the resulting copolymer. Furthermore, the composition was analyzed by hydrogen nuclear magnetic resonance (1H NMR), which is consistent with the feed ratio of monomers. Blending of the branched product with high density polyethylene (HDPE) was attempted in haake mixer. The rheological, mechanical, and thermal stability properties of the resulting blends were studied. Compared with pure HDPE, the complex viscosity of blend with addition of 4 wt % BPSDA decreased by 15.9%. While the elongation at break decreased by 5.5% and tensile strength decreased by 4.2%. SEM (scanning electron microscopy) revealed that the average particle size of disperse phase in HDPE/4% BPSDA blend is 0.45 μm in diameter. Differential scanning calorimetry characterization showed that the addition of BPSDA accelerated the relative crystallization rate but decreased the final absolute degree of crystallinity. No obvious change of thermal stability of the blends was observed relative to pure HDPE. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Preparation and characterization of polymer‐based spherical activated carbons with tailored pore structure
Authors: Zhu Zhaolian , Li Aimin , Zhong Sheng , Liu Fuqiang , Zhang Quanxing 
Published: April 2008

AbstractA series of spherical activated carbons (SACs) with different pore structure were prepared from divinylbenzene‐based polymer through CO2 activation. The effect of activation temperature and retention time on the yield and textural properties of the resulting SACs were studied. The SACs were characterized by N2 adsorption, X‐ray diffraction, scanning electron microscopy, and aqueous adsorption assays. Either increasing activation temperature or extending retention time decreases the yield of SACs. The BET surface area and pore volume increase with activation temperature and reach a maximum at 1000°C and then decrease at higher activation temperatures. At 1000°C, BET surface area, total pore volume, and mesopore pore volume increase with retention time from 0.5 to 2 h, and meanwhile micropore volume decreases. The micropores are gradually widened into mesopores with increasing activation temperature or extending retention time. SEM and XRD analyses of SAC10 verify the presence of developed porous structure composed of disordered micrographite stacking. Aqueous adsorption assays indicate that SACs have good adsorption capacity for phenol. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Conservation of threatened species in the Galapagos Marine Reserve through identification and protection of marine key biodiversity areas
Authors: Edgar Graham J. , Banks Stuart , Bensted‐Smith Robert , Calvopiña Monica , Chiriboga Angel , Garske Lauren E. , Henderson Scott , Miller Kathy Ann , Salazar Sandie 
Published: April 2008

Abstract
The Galapagos Marine Reserve provides refuge for numerous threatened marine species, including 16 mammals, birds, reptiles and fish currently recognized on the 2006 IUCN Red List of Threatened Species, plus an additional 25 endemic fish, mollusc, crustacean, echinoderm, coral and macroalgal species that comply with threatened species criteria because of declining extent of occurrence or highly‐localized ranges, and hence also qualify for inclusion on the Red List.
Threatened marine species with restricted ranges are not randomly distributed across the archipelago but tend to co‐occur at a limited number of sites that are predominantly located in the west. Sites at which threatened species are known to persist, particularly those with a large proportion of the global population, are here identified as sites of global conservation significance — key biodiversity areas.
The majority (27) of the 38 inshore key biodiversity areas identified are currently protected from fishing because they lie within the 17% of coastal waters that is zoned as ‘no‐take’ tourism or conservation zones. All key biodiversity areas should be protected from extractive exploitation if threatened species are to be safeguarded. This can be achieved, at the minimum, through a relatively minor amendment to the existing marine zoning scheme, whereby an additional 2% of the coastline is dedicated to conservation.
Copyright © 2008 John Wiley & Sons, Ltd.
Implications of decoupling the intracellular and extracellular levels in multi‐level models of virus growth
Authors: Haseltine Eric L. , Yin John , Rawlings James B. 
Published: April 2008

AbstractVirus infections are characterized by two distinct levels of detail: the intracellular level describing how viruses hijack the host machinery to replicate, and the extracellular level describing how populations of virus and host cells interact. Deterministic, population balance models for viral infections permit incorporation of both the intracellular and extracellular levels of information. In this work, we identify assumptions that lead to exact, selective decoupling of the interaction between the intracellular and extracellular levels, effectively permitting solution of first the intracellular level, and subsequently the extracellular level. This decoupling leads to (1) intracellular and extracellular models of viral infections that have been previously reported and (2) a significant reduction in the computational expense required to solve the model. However, the decoupling restricts the behaviors that can be modeled. Simulation of a previously reported multi‐level model demonstrates this decomposition when the intracellular level of description consists of numerous reaction events. Additionally, examples demonstrate that viruses can persist even when the intracellular level of description cannot sustain a steady‐state production of virus (i.e., has only a trivial equilibrium). We expect the combination of this modeling framework with experimental data to result in a quantitative, systems‐level understanding of viral infections and cellular antiviral strategies that will facilitate controlling both these infections and antiviral strategies. Biotechnol. Bioeng. 2008;101: 811–820. © 2008 Wiley Periodicals, Inc.
Ethanol and hydrogen production by two thermophilic, anaerobic bacteria isolated from Icelandic geothermal areas
Authors: Koskinen Perttu E.P. , Beck Steinar R. , Örlygsson Jóhann , Puhakka Jaakko A. 
Published: April 2008

AbstractMicrobial fermentations are potential producers of sustainable energy carriers. In this study, ethanol and hydrogen production was studied by two thermophilic bacteria (strain AK15 and AK17) isolated from geothermal springs in Iceland. Strain AK15 was affiliated with Clostridium uzonii (98.8%), while AK17 was affiliated with Thermoanaerobacterium aciditolerans (99.2%) based on the 16S rRNA gene sequence analysis. Both strains fermented a wide variety of sugar residues typically found in lignocellulosic materials, and some polysaccharides. In the batch cultivations, strain AK17 produced ethanol from glucose and xylose fermentations of up to 1.6 mol‐EtOH/mol‐glucose (80% of the theoretical maximum) and 1.1 mol‐EtOH/mol‐xylose (66%), respectively. The hydrogen yields by AK17 were up to 1.2 mol‐H2/ mol‐glucose (30% of the theoretical maximum) and 1.0 mol‐H2/mol‐xylose (30%). The strain AK15 produced hydrogen as the main fermentation product from glucose (up to 1.9 mol‐H2/mol‐glucose [48%]) and xylose (1.1 mol‐H2/mol‐xylose [33%]). The strain AK17 tolerated exogenously added ethanol up to 4% (v/v). The ethanol and hydrogen production performance from glucose by a co‐culture of the strains AK15 and AK17 was studied in a continuous‐flow bioreactor at 60°C. Stable and continuous ethanol and hydrogen co‐production was achieved with ethanol yield of 1.35 mol‐EtOH/mol‐glucose, and with the hydrogen production rate of 6.1 mmol/h/L (H2 yield of 0.80 mol‐H2/mol‐glucose). PCR‐DGGE analysis revealed that the AK17 became the dominant bacterium in the bioreactor. In conclusion, strain AK17 is a promising strain for the co‐production of ethanol and hydrogen with a wide substrate utilization spectrum, relatively high ethanol tolerance, and ethanol yields among the highest reported for thermoanaerobes. Biotechnol. Bioeng. 2008;101: 679–690. © 2008 Wiley Periodicals, Inc.
Self‐Assembled Double‐Shelled Ferrihydrite Hollow Spheres with a Tunable Aperture
Authors: Wu Zhengcui , Zhang Miao , Yu Kuai , Zhang Shudong , Xie Yi 
Published: April 2008

AbstractNovel double‐shelled hierarchical ferrihydrite hollow spheres (Fe10O14(OH)2⋅4 H2O) were successfully synthesized on a large scale by using a facile medicine‐inspired solution‐phase approach. Sodium nitroprusside (SNP), an ordinary and inexpensive medicine for expanding blood vessels, served as both a ferric source and an in situ formed gas‐bubble template with the presence of sodium dihydrogen phosphate as a pH regulator, coordinator, and stabilizer. A twice‐gas‐bubble template model has been proposed for the formation of the double‐shelled hollow spheres to take advantage of the dissociation and hydrolyzation of the two kinds of ligands in the SNP precursor. The size of the double‐shelled ferrihydrite hollow spheres can be tuned by varying the experimental parameters. As‐obtained ferrihydrite is highly sensitive to ethanol gas, which indicates potential applications in the field of sensing devices.
Convergence analysis of general neural networks under almost periodic stimuli
Authors: Huang Zhenkun , Mohamad S. , Wang Xinghua , Feng Chunhua 
Published: April 2008

AbstractIn this paper, we investigate the convergence dynamics of 2N almost periodic encoded patterns of general neural networks subjected to external almost periodic stimuli, including almost periodic delays. Invariant regions are established for the existence of 2N almost periodic encoded patterns under two classes of activation functions. By employing the property of ℳ︁‐cone and inequality technique, attracting basins are estimated and some criteria are derived for the networks to converge exponentially toward 2N almost periodic encoded patterns. The results obtained are new; they extend and generalize the corresponding results existing in the previous literature. Copyright © 2008 John Wiley & Sons, Ltd.
Thin ideal internalization in Mexican girls: A test of the sociocultural model of eating disorders
Authors: Austin Julia L. , Smith Jane Ellen 
Published: April 2008

AbstractObjective:We examined the influence of thin ideal internalization on body dissatisfaction and disordered eating in Mexican girls.Method:We sampled 137 public school girls aged 12–15 from a small city in Mexico. Participants were given Spanish versions of the sociocultural attitudes toward appearance scale, two measures of body dissatisfaction, the eating attitudes test, and the attitudinal familism scale.Results:Thin ideal internalization mediated the relationship between thin ideal awareness and body dissatisfaction, and the relationship between thin ideal awareness and eating disorder symptoms. Attitudinal familism was negatively correlated with thin ideal internalization for girls outside of the normal weight range.Conclusion:Mexican girls are at risk of eating disorder symptoms, and there is support for the sociocultural model of disordered eating in this population. Hispanic family values may mark protection from thin ideal internalization in Mexican girls outside of the normal weight range. © 2008 by Wiley Periodicals, Inc. Int J Eat Disord 2008
The point prevalence of bulimic disorders from 1990 to 2004
Authors: Crowther Janis H. , Armey Michael , Luce Kristine H. , Dalton Ginnie R. , Leahey Tricia 
Published: April 2008

AbstractObjective:This study investigated the point prevalence of probable cases of bulimia nervosa (BN), eating disorder not otherwise specified (EDNOS), and specific eating disorder symptomatology among 6,844 undergraduate women at a single site, examining changes across five 3‐year time periods and on a yearly basis from 1990 to 2004.Method:Participants completed a self‐report checklist that assessed the diagnostic criteria for BN (American Psychiatric Association, Diagnostic and Statistical Manual of Mental Disorders, 1994) and the Bulimia Test (Smith and Thelen, J Consult Clin Psychol, 52, 863–872, 1984) (BULIT) or Bulimia Test‐Revised (Thelen et al., Psychol Assess, 3, 119–124, 1991) (BULIT‐R).Results:Chi‐square analyses comparing the percentages of probable cases of BN and EDNOS and the percentages of women who reported frequent binge eating and most compensatory weight control strategies were nonsignificant. Only the percentages of women who endorsed overconcern with weight and shape and diuretic use and excessive exercise as compensatory weight control strategies changed over time.Conclusion:Consistent with Keel et al.'s (Keel et al., Psychol Med, 36, 119–127, 2006) findings regarding the point prevalence rates of BN from 1992 to 2002, results indicated that probable cases of eating disorders remained relatively stable. Methodologically, this research illustrates the importance of examining multiple data points when investigating stability or change in behavior. © 2008 by Wiley Periodicals, Inc. Int J Eat Disord 2008
Online discussion groups for bulimia nervosa: An inductive approach to Internet‐based communication between patients
Authors: Wesemann Dorette , Grunwald Martin 
Published: April 2008

AbstractObjective:Online discussion forums are often used by people with eating disorders.Method:This study analyses 2,072 threads containing a total of 14,903 postings from an unmoderated German “prorecovery” forum for persons suffering from bulimia nervosa (www.ab‐server.de) during the period from October 2004 to May 2006. The threads were inductively analyzed for underlying structural types, and the various types found were then analyzed for differences in temporal and quantitative parameters.Results:Communication in the online discussion forum occurred in three types of thread: (1) problem‐oriented threads (78.8% of threads), (2) communication‐oriented threads (15.3% of threads), and (3) metacommunication threads (2.6% of threads). Metacommunication threads contained significantly more postings than problem‐oriented and communication‐oriented threads, and they were viewed significantly more often. Moreover, there are temporal differences between the structural types.Conclusion:Topics relating to active management of the disorder receive great attention in prorecovery forums. © 2008 by Wiley Periodicals, Inc. Int J Eat Disord 2008
Study on vibration caused by electromagnetic force in the end portion of large‐capacity cylindrical synchronous machines: Improvement of electromagnetic force estimation and verification of degradation on winding insulation
Authors: Nagano Susumu , Tokumasu Tadashi , Fujita Masafumi , Inoue Yoshiyuki , Ichimonji Masayuki , Katayama Hitoshi , Hiramatsu Daisuke , Nitta Tanzo 
Published: April 2008

AbstractA new method for analyzing electromagnetic force in the end‐winding portion of large‐capacity synchronous generators is provided and evaluated in comparison with 3D FEM electromagnetic analysis. In addition, a method for estimating end‐winding vibration during on‐load operation is suggested by measured data at factory testing. Moreover, an evaluation method for insulation degradation after operation is proposed for large‐capacity cylindrical synchronous machines, where the end‐winding portion is the longest and electromagnetic forces on it are the greatest of all rotating machinery. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 163(4): 78–89, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20666
Evaluation of polarization angle rotation of propagating light in a partially ionized atmosphere under discharge conditions
Authors: Shiina Tatsuo , Honda Toshio , Fukuchi Tetsuo 
Published: April 2008

AbstractThe polarization angle rotation of the propagating beam was estimated in a partially ionized atmosphere under discharge conditions. The polarization plane angle rotation is caused by the magneto‐optical effect (Faraday effect). The estimated rotation angle is of the order of <1 degree, but can be detected with an extinction ratio of polarization of >30 dB. We examined the effects of the optical path length of repeating square mirror optics and an air‐gap length of the discharge on the rotation angle. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 163(4): 1–7, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20689
Metal‐Organic Frameworks (MOFs) Composed of (Triptycenedicarboxylato)zinc
Authors: Vagin Sergei , Ott Anna , Weiss Hans‐Christoph , Karbach Alexander , Volkmer Dirk , Rieger Bernhard 
Published: April 2008

AbstractTwo novel 2D and 3D coordination polymers of 9,10‐triptycenedicarboxylic acid and zinc nitrate, which form under solvothermal reaction conditions, are described. As determined by single‐crystal X‐ray structure analysis, their frameworks are assembled from dinuclear zinc coordination units which are interlinked by triptycenedicarboxylato (TDC) struts. In the 2D‐MOF reported here, the extended network of van der Waals interactions between triptycene units as well as coordinated solvent molecules is responsible for the dense assembly of layers with a 44 net topology into the final crystal structure. The framework of the 3D‐MOF is composed from [Zn2(TDC)1.5]∞ layers with a 63 topology, the layers being interlinked by triptycenedicarboxylato pillars (bnn‐net). This MOF possesses hexagonal channels which are filled with guest molecules.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Nanostructured Titania–Diphosphonate Hybrid Materials with a Porous Hierarchy
Authors: Zhang Xue‐Jun , Ma Tian‐Yi , Yuan Zhong‐Yong 
Published: April 2008

AbstractAn organic–inorganic hybrid nanostructured material of titania–diphosphonate (Ti‐HEDP) was prepared from a simple self‐assembly process with the precursor tetrabutyl titanate and 1‐hydroxyethane‐1,1‐diphosphonic acid (HEDP). The prepared hybrid Ti‐HEDP has a semicrystalline anatase phase, exhibiting a hierarchical macroporous structure composed of mesostructured Ti‐HEDP nanorods with a length of 80–150 nm and a thickness of 18–38 nm. The BET surface area is 257 m2/g. The 1‐hydroxyethane‐1,1‐diyl‐bridged organophosphonate groups were homogeneously incorported into the network of the hierarchical nanostructured/porous solid, as revealed by FT‐IR spectroscopy, MAS NMR spectroscopy, XPS, and TGA measurements. The optical property, photocatalytic activity, and metal ion adsorption ability of the hierarchical Ti‐HEDP materials were also investigated, suggesting that they have potential applications in catalysis and adsorption.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Nitroamino Triazoles: Nitrogen‐Rich Precursors of Stable Energetic Salts
Authors: Huang Yangen , Gao Haixiang , Twamley Brendan , Shreeve Jean'ne M. 
Published: April 2008

Abstract1‐Nitroamino‐1,2,3‐triazole (5) was synthesized and its zwitterionic structure was established using single‐crystal X‐ray diffraction. The calculated detonation properties for 4‐nitroamino‐1,2,4‐triazole (2) (P= 33.4 GPa,vD= 8793 m/s) and 1‐nitroamino‐1,2,3‐triazole (5) (P= 33.0 GPa,vD= 8743 m/s) are comparable with RDX. A new family of energetic salts7–21based on either the 1‐nitroamino‐1,2,3‐triazolate or the 4‐nitroamino‐1,2,4‐triazolate anion were prepared and characterized by vibrational spectroscopy (IR), multinuclear NMR spectra, elemental analyses, density, TGA and DSC. The heats of formation (ΔfH°298) and detonation properties for these stable salts were calculated using Gaussian 03 and Cheetah 4.0, respectively. Comparison of the properties of the 1,2,3‐ and 1,2,4‐triazolate salts indicates that while the 1,2,4‐derivatives are more stable thermally, the 1,2,3‐analogs invariably have higher heats of formation. In contrast to its salts, 1‐nitroamino‐1,2,3‐triazole (5) is extremely shock‐sensitive with an impact sensitivty of <1 J. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Synthesis of the Mannopeptimycin Disaccharide and Its Conjugation with 4‐Alkylidene‐β‐lactams
Authors: Adinolfi Matteo , Giacomini Daria , Iadonisi Alfonso , Quintavalla Arianna , Valerio Silvia 
Published: April 2008

AbstractThe disaccharide moiety of the antibiotic mannopeptimycin has been synthesized as a (N‐phenyl)trifluoroacetimidate donor, the reactivity of which was tested in conjugation with a 4‐alkylidene‐β‐lactam acceptor. Key steps of the synthesis were Bi(OTf)3‐catalyzed glycosidations that proceeded in short times and with high yields and stereocontrol. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
On the Mechanism of Gold(I)‐Catalyzed Ring Expansion of Cyclopropanols: Theoretical Calculations Uncover a Bottle‐Neck 1,4‐H Shift and Suggest Adequate Reaction Conditions
Authors: Sordo Tomás L. , Ardura Diego 
Published: April 2008

AbstractThe mechanism of the one‐carbon ring‐expansion reactions of 1‐(1‐propynyl)cyclopropanol (1; R = Me), (1R*,2R*)‐1‐ethynyl‐2‐isopropylcyclopropanol (3), and (1R*,2S*)‐1‐(phenylethynyl)‐2‐isopropylcyclopropanol (4) catalyzed by [AuP(Ph)3]+ to yield the corresponding 2‐alkylidenecyclobutanones was theoretically investigated by B3LYP‐PCM calculations by using the LANL2DZ relativistic effective core potential for Au and the 6‐31G(d) basis set for the remaining atoms. The most favorable route for these rearrangements in dichloromethane solution is a two‐step mechanism involving as the first step the coordination of the gold(I) complex to the alkyne moiety with subsequent evolution through a 1,2‐alkyl shift. Activation of the reactive C–C bonds takes place mainly through hyperconjugative interactions of these bonds with the oxygen atom and the alkyne moiety; this latter interaction is reinforced by the presence of the cationic gold(I) complex. The second step is the rate‐determining one and consists of a 1,4‐H shift, which requires the assistance by a second molecule of cyclopropanol to become readily accessible. This second molecule plays a very efficient bifunctional catalytic role, which cannot be played by a dichloromethane molecule. The use of methanol, water, and HFIP as assisting molecules was also investigated. Calculations suggest that the process would run most favorably in water. In agreement with experimental data, we found that the most favorable ring expansion of 3 takes place through migration of the substituted carbon atom. The only product to be expected from the rearrangement of 4, however, is that corresponding to the migration of the nonsubstituted carbon atom.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)