bluuebunny/crossref_metadata_2025_split huggingface dataset:
Enthalpies of formation and isomerization of aromatic hydrocarbons and ethers by G3(MP2)//B3LYP calculations
Authors: Taskinen Esko 
Published: December 2008

AbstractA computational method for estimation of the gas‐phase enthalpies of formation of aromatic hydrocarbons and ethers has been developed. The method is based on high‐level G3(MP2)//B3LYP calculations, atomization reactions, and structure‐dependent correction terms. By this method, enthalpies of formation ΔfHm°(g, 298.15 K) of 86 aromatic compounds were evaluated. The calculated enthalpies of formation raise questions of the reliability of several experimental enthalpies of formation reported in the literature. As an application of the computational enthalpies of formation, reaction enthalpies for several types of isomerization reactions of aromatic compounds were calculated. In cases in which experimental reaction enthalpies were available for comparison, the agreement between the computational and experimental data proved to be excellent. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis of 1H‐quinazoline‐2,4‐diones from 2‐aminobenzonitriles by fixation of carbon dioxide with amidine moiety supported polymer at atmospheric pressure
Authors: Nagai Daisuke , Endo Takeshi 
Published: December 2008

Abstract1H‐Quinazoline‐2,4‐diones, which are key intermediates in the synthesis of medicines, were successfully synthesized from 2‐aminobenzonitriles by the fixation of CO2 in the presence of a polystyrene derivative bearing amidine moiety [poly(amidine)]. A model reaction, that is, the reaction of 2‐aminobenzonitrile (1a) with CO2 in the presence of N‐methyltetrahydropyrimidine (MTHP) revealed that a catalytic amount of MTHP afforded 1H‐quinazoline‐2,4‐dione (2a) quantitatively at atmospheric pressure. Several 1H‐quinazoline‐2,4‐diones (2a‐2c) were successfully synthesized from the corresponding 2‐aminobenzonitriles (1a‐1c) in the presence of poly(amidine). The poly(amidine) could easily be separated from the reaction mixture by filtration and reused in subsequent reactions owing to the heterogeneous system. These demonstrated that poly(amidine) is a useful heterogeneous polymer‐supported reagent for the synthesis of 1H‐quinazoline‐2,4‐diones from CO2. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 653–657, 2009
Nano‐hydroxyapatite/polyamide66 composite tissue‐engineering scaffolds with anisotropy in morphology and mechanical behaviors
Authors: Wang Huanan , Zuo Yi , Zou Qin , Cheng Lin , Huang Di , Wang Li , Li Yubao 
Published: December 2008

AbstractBased on a biomimetic conception, nano‐hydroxyapatite (n‐HA)/polyamide66 (PA66) composite scaffolds were prepared with anisotropic properties both in morphology and mechanical behavior. A novel improved thermally induced phase separation (TIPS) technique was developed to generate orientation‐structured scaffolds for tissue engineering. The physiochemical, morphological, and mechanical properties of the resultant scaffolds were evaluated. According to the results, the improved TIPS method exhibited good processability and reproducibility and enabled the composite scaffolds to have a high content of inorganic fillers. The morphological study proved that the n‐HA/PA66 scaffolds exhibited unidirectional microtubular architecture with high porosity (ca. 80–85%) and an optimal pore size ranging from 200 to 500 μm. Besides, the effect of n‐HA content on the morphology of the scaffolds was studied, and the results indicated that the obtained scaffolds presented an improvement in anisotropic morphology with increase of n‐HA content. The anisotropy was also evaluated in the mechanical properties of the scaffolds, that is, the longitudinal compressive strength and modulus were ∼1.5 times of the transverse ones. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 658–669, 2009
Thermoplastic amphiphilic conetworks
Authors: Kang Jungmee , Erdodi Gabor , Kennedy Joseph P. 
Published: December 2008

AbstractOur main objective was the design, synthesis, characterization, and testing of a novel class of materials, thermoplastic amphiphilic conetworks (TP‐APCNs). A further objective was the evaluation of TP‐APCNs as biomaterials, for example, as immunoisolatory membranes in a bioartificial pancreas, or as extended‐wear soft contact lenses. The synthesis of the first TP‐APCNs was accomplished by blending an amphiphilic graft polymer, poly(dimethyl acryl amide)‐g‐polydimethylsiloxane (PDMAAm‐g‐PDMS), with a commercial PDMS‐containing polyurethane (PU). The common PDMS segments coalesce and form a single phase, whereas the hard/crystalline segments of the PU physically crosslink the blend. The properties of TP‐APCNs can be controlled by the graft/PU ratio and segment molecular weights. TP‐APCNs with cocontinuous hydrophilic and hydrophobic phases were prepared as demonstrated by swelling in water and n‐heptane. Depending on the blend ratio and molecular weights, optically clear water‐swollen TP‐APCNs with 0.5–4 MPa tensile strength, 70–280% elongation, together with 2–11 × 10−7 cm2/s glucose permeability, and 1.2–8 × 10−8 cm2/s insulin permeability were prepared. TP‐APCNs are processible by casting and molding. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 682–691, 2009
Synthesis, characterization, and thermal properties of piezoelectric polyimides
Authors: Gonzalo B. , Vilas J. L. , Breczewski T. , Pérez‐Jubindo M. A. , De La Fuente M. R. , Rodriguez M. , León L. M. 
Published: December 2008

AbstractThree amorphous piezoelectric polyimides have been synthesized and characterized to analyze their utility for high‐temperature applications. The studied polyimides have been prepared from 4,4′‐oxydiphthalic anhydride and the diamines 2,4‐di(3‐aminophenoxy)benzonitrile (poly2‐4), 2,6‐bis(3‐aminophenoxy)benzonitrile (poly2‐6), and 1,3‐bis‐2‐cyano‐3‐(3‐aminophenoxy)phenoxybenzene (poly2CN). These polyimides differ in the position of the dipolar groups CN in the aromatic ring (poly2‐4 and poly2‐6) and in the number of these groups in the repetitive unit (poly2‐6 and poly2CN). The imidization degree has been studied by Fourier transform infrared (FTIR) and thermogravimetry‐mass spectrometry (TG‐MS) and thermal properties by differential scanning calorimetry (DSC) and thermogravimetry (TG). The piezoelectric behavior has been analyzed from remnant polarization measurements. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 722–730, 2009
Influence of number of functional groups of hyperbranched polyol on cure kinetics and physical properties of polyurethanes
Authors: Maji Pradip K. , Bhowmick Anil K. 
Published: December 2008

AbstractCuring of polyurethane prepolymer with three hyperbranched polyol was studied using FTIR spectroscopy. The disappearance of the strong isocyanate absorption peak was followed with time and temperature to determine the reaction kinetics. It was shown that all the hyperbranched polyols followed the second order kinetic equation and the reaction rate enhanced with increase in the number of the functional groups of the hyperbranched polyol. Activation energy, activation enthalpy, and activation entropy were also measured. The swelling character of the polyurethanes was investigated with the help of gel fraction, degree of crosslinking, and average molecular weight between crosslinks. Atomic force microscopy indicated phase separated morphology of the cured polyurethanes. The thermal, mechanical, and thermomechanical properties were enhanced when the number of the functional groups in the hyperbranched polyols was increased. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 731–745, 2009
Microemulsion polymerization of cationic pyrroles bearing an imidazolum‐ionic liquid moiety
Authors: Zhao Jie , Yan Feng , Chen Zhenzhen , Diao Hanbin , Chu Fuqiang , Yu Shaomei , Lu Jianmei 
Published: December 2008

AbstractA cationic pyrrole derivative, N‐(4‐butyl‐(1‐methylimidazole)) pyrrole bromide (Py‐Br) bearing an imidazolium‐type ionic liquid moiety was synthesized. Microemulsion polymerization of Py‐Br in water/oil microemulsions produced poly(N‐(4‐butyl‐(1‐methylimidazole)) pyrrole bromide) (PPy‐Br) nanoparticles. The bromide anion of the resultant PPy‐Br nanoparticles was exchanged in water with different anions, including BF and PF to produce new nanoparticles bearing different counteranions. The results of thermal analysis indicate that the thermal stability of cationic PPy nanoparticles strongly depends on the nature of counteranion. As an application, water‐soluble PPy‐Br with fine fluorescence property was used as a new sensor for DNA detection. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 746–753, 2009
Heterogeneous polymerization with polyaspartate macromonomer having vinyl pendant groups. I. Synthesis of macromonomer and dispersion copolymerization of styrene
Authors: Tomita Keisuke , Ono Tsutomu 
Published: December 2008

AbstractSodium polyaspartate (PAspNa) derivatives with vinylbenzyl pendant groups (VBA‐PAspNa) were synthesized by reaction of poly(succinimide) (PSI) and vinylbenzylamine (VBA), and hydrolysis by sodium hydroxide (NaOH) solution. VBA‐PAspNa is a macromonomer with multiple vinyl groups in the side chain. Submicron sized polymeric particles were prepared by dispersion copolymerization of styrene with VBA‐PAspNa in a mixture of ethanol and water. Particle diameter decreased with increasing concentration and vinyl group fraction of VBA‐PAspNa. When compared with the particle diameter prepared using PAspNa or benzylamine‐modified PAspNa (BA‐PAspNa) as a dispersion stabilizer without vinyl groups, the particles prepared with VBA‐PAspNa were an order smaller than those prepared with PAspNa or BA‐PAspNa. The particles after refinement show an adequate negative ζ‐potential. From this result, we clarified the presence of PAspNa chains anchored onto the particle surface. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 762–770, 2009
Polymerization kinetics of rac‐lactide initiated with alcohol/stannous octoate using in situ attenuated total reflectance‐fourier transform infrared spectroscopy: An initiator study
Authors: Moravek Scott J. , Messman Jamie M. , Storey Robson F. 
Published: December 2008

Abstractrac‐Lactide polymerization kinetics in THF at 72 °C were monitored in real‐time using mid‐infrared ATR‐FTIR spectroscopy, with diamond composite insertion probe and light conduit technology. Monomer concentration as a function of time was acquired using the 1240 cm−1 resonance associated with the COOC stretch. Polymerizations were initiated with either n‐propanol (PrOH), ethylene glycol (EG), trimethylol propane (TMP), or pentaerythritol (PENTA) with the coinitiator stannous octoate (Sn(Oct)2). Polymerizations were found to be reversible at high monomer conversions, with a residual monomer concentration at 72 °C (345 K) of 0.081 M. The polymerizations were internally first‐order with respect to monomer, indicating a constant concentration of propagating centers. For a typical reaction with [rac‐LA]0 = 1.0 M, [PENTA]0 = 1.3 × 10−2 M, and [Sn(Oct)2] = 2.5 × 10−2 M, the first‐order rate constant, kapp was measured as 1.8 × 10−4 s−1. First‐order rate constants were determined to be independent of polymer architecture (i.e., initiator functionality) and proportional to [Sn(Oct)2] for [Sn(Oct)2]0/[ROH]0 ≪ 1, where [ROH]0 represents the initial concentration of initiating hydroxyl groups. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 797–803, 2009
Synthesis and characterization of polypropylene‐based block copolymers possessing polar segments via controlled radical polymerization
Authors: Kaneko Hideyuki , Saito Junji , Kawahara Nobuo , Matsuo Shingo , Matsugi Tomoaki , Kashiwa Norio 
Published: December 2008

AbstractA new method to prepare the polypropylene (PP) macroinitiator for controlled radical polymerization was described. Bromination of terminally‐unsaturated PP was carried out by using N‐bromosuccinimide and 2,2′‐azobis(isobutyronitrile) to give a brominated PP (PP‐Br), that has allylic bromide moieties at or near the chain ends. Thus, the obtained PP‐Br was successfully used as a macroinitiator for radical polymerization of styrene, methyl methacrylate, and n‐butyl acrylate using a copper catalyst system. From 1H NMR analysis, it was confirmed that the chain extension polymerization was certainly initiated from allylic bromide moieties with high efficiency, leading to the PP‐based block copolymers linking the polar segment. From differential scanning calorimetry, it was observed that peak melting temperature of block copolymers was higher than that of PP‐Br and the obtained PP‐PS block copolymers with different compositions of each segment demonstrated the unique morphological features due to the microphase separation between both segments. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 812–823, 2009
Sexual health issues in Sudanese women before and during hormonal treatment for breast cancer
Authors: Abasher Sanaa M. 
Published: December 2008

AbstractObjective: Recent Sudanese studies have focused on depression and anxiety in women treated for breast cancer (BrCa). Less is known about whether such women suffer from sexual disturbances due to different cancer treatments. This study compares BrCa patients with a healthy control group and assessed the impact of cancer treatment types.Methods: The BrCa group included women treated for BrCa with mastectomies, chemotherapy and radiotherapy (N=100). Some received hormonal therapy (N=60) and others had not yet received it (N=40). The control group comprised women who had never had BrCa, non‐BrCa (N=100). Outcomes were assessed using the Watts Sexual Function Questionnaire.Results: It was found that many women treated for BrCa suffered from sexual disturbances before hormonal treatment while some regained sexual activity during hormonal treatment. Demographic data show negative correlation (P=0.03) between sexual function and age of the patients, positive correlation (P=0.002) between sexual function and educational level and positive correlation (P=0.031) as well between sexual function and the patient's length of marriage.Conclusion: This study helps to fill the gap in the literature about Sudanese women's sexuality, as many studies indicate the effect of some psychological disturbance (depression and anxiety) and ignoring the effect of sexual function in enhancing patient's quality of life. Copyright © 2008 John Wiley & Sons, Ltd.
Separation and Determination of PETN and TNT by HPTLC
Authors: Chaloosi Marzieh , Nejad‐Darzi Seyed Karim Hassani , Ghoulipour Vanik 
Published: December 2008

AbstractThis article was published in Early View with DOI 10.1002/prep.200800012 – what is wrong. It has appeared with the correct DOI 10.1002/prep.200900012 – in Propellants, Explosives, Pyrotechnics 2009 (34) issue 1/2009 on pp 50‐52.
Lack of fitness costs associated with pyriproxyfen resistance in the B biotype of Bemisia tabaci
Authors: Crowder David W , Ellers‐Kirk Christa , Tabashnik Bruce E , Carrière Yves 
Published: December 2008

AbstractBACKGROUND: The insect growth regulator pyriproxyfen has provided effective control of the whitefly Bemisia tabaci Gennadius in many countries. Here, whether or not fitness costs were associated with pyriproxyfen resistance in a laboratory‐selected resistant strain (QC02‐R) of the B biotype was determined.RESULTS: Mortality caused by pyriproxyfen and fitness traits over time were measured in unselected and selected hybrid strains, which were created by crossing individuals of the resistant strain with individuals of a susceptible strain. Fitness costs were not associated with resistance in QC02‐R, as mortality caused by pyriproxyfen did not increase over time in unselected hybrid strains and fitness traits were similar in unselected and selected hybrid strains. Using a new method to examine the inheritance of resistance, based on data from fitness cost experiments, it was estimated that pyriproxyfen resistance is controlled by two loci in the QC02‐R strain.CONCLUSION: The lack of fitness costs associated with pyriproxyfen resistance could promote the evolution of resistance in field populations with similar traits to QC02‐R. Copyright © 2008 Society of Chemical Industry
Improvement of peptide vectors for gene delivery with active targeting profiles for phosphatidylserine
Authors: Kuriyama Shinichi , Taguchi Yasushi , Nishimura Kanako , Yanagibashi Kazutoshi , Katayama, Yoshiki , Niidoime Takuro 
Published: December 2008

AbstractA cationic peptide, Td3701, which was derived from factor VIII that has affinity with phosphatidylserine (PS), showed efficient transfection ability for cells that express PS on the cell surface. PS is exposed on tumor cell surfaces therefore we have focused on PS as the target molecule for tumor specific gene delivery. In this article, to improve transfection efficiency and specificity in targeting tumor cells, some amino acid residues of Td3701 were replaced. The resulting peptide, Td3717, shows higher transfection efficiency (more than 30 times that of Td3701). The transfection efficiency was dependent on the amount of PS on the cell surface, suggesting that Td3717 bound with plasmid DNA could recognize PS on the cell surface. Td3717 is expected to be useful as an efficient gene carrier molecule specific to PS‐presenting tumor cells. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd.
Interstate migration, spatial assimilation, and the incorporation of US immigrants
Authors: Hall Matthew 
Published: December 2008

AbstractThe recent trend of immigrant geographical diffusion in the United States has increased the relevance of a detailed understanding of the consequences of secondary migration for immigrant families, and a consideration of what is to be learned about immigrant incorporation from their patterns of domestic migration. In this paper, a regional variant of the spatial assimilation model is tested using longitudinal data on immigrant economic well‐being. The results of this research indicate that, like their native counterparts, immigrants benefit, both in terms of employment and earnings, from making interstate moves. Consistent with the spatial assimilation model, immigrants migrating to states with smaller relative foreign‐born populations see additional gains, with higher‐skilled and better‐acculturated immigrants enjoying the greatest returns. Copyright © 2009 John Wiley & Sons, Ltd.
Mining the bulk positron lifetime
Authors: Aourag H. , Guittom A. 
Published: December 2008

AbstractWe introduce a new approach to investigate the bulk positron lifetimes of new systems based on data‐mining techniques. Through data mining of bulk positron lifetimes, we demonstrate the ability to predict the positron lifetimes of new semiconductors on the basis of available semiconductor data already studied. Informatics techniques have been applied to bulk positron lifetimes for different tetrahedrally bounded semiconductors in order to discover computational design rules. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electronic structure, optical and X‐ray emission spectra in FeS2
Authors: Antonov V. N. , Germash L. P. , Shpak A. P. , Yaresko A. N. 
Published: December 2008

AbstractThe electronic structure, optical spectra, X‐ray emission (XE) and X‐ray absorption (XA) spectra of FeS2 were investigated theoretically from first principles, using the fully relativistic Dirac LMTO band structure method in local density approximation (LDA). Theory produces correct semiconductor ground state in FeS2 with the energy gap of Eg = 0.9 eV in good agreement with the experimental data. Densities of valence states are analyzed and discussed. The origin of the optical, XA and XE spectra in the FeS2 compound is examined. The calculated results are compared with available experimental data. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Novel electronic structure and transport properties of confined disordered carbon layers
Authors: Bhattacharyya Somnath 
Published: December 2008

AbstractWe propose a generalized spectral conductivity model for combined delocalized and localized π‐states of low‐dimensional carbon to explain their temperature dependent conductivity and its crossover. This model also interprets the origin of weakly localized coherent transport in carbon super‐structures such as nano‐crystalline diamond and 2D carbon films. From the enhanced phase coherence length the unique microstructure of these films is revealed. The corresponding electron's dephasing time also shows their potential for fast electronic device applications. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Improved luminescence efficiency of InAs quantum dots grown on atomic terraced GaAs surface prepared with in‐situ chemical etching
Authors: Idutsu Yasuhiro , Miyamura Souta , Suemune Ikuo 
Published: December 2008

AbstractObservation of the enhanced luminescence efficiency of InAs quantum dots (QDs) grown on atomically controlled GaAs surfaces is reported. With the trisdimethylaminoarsenic (TDMAAs) in‐situ surface etching process, formation of atomic steps and terraces on GaAs surfaces were clearly observed. InAs QDs grown on the processed GaAs surfaces showed the clear dependence of QDs size, density and optical characteristics on the surface properties, i.e., the increase of the QDs height and diameter the decrease of the QDs density. About 6‐times enhancement of photoluminescence efficiency which has the peak around 1550‐nm wavelength was observed by growing InAs QDs on atomically controlled GaAs surfaces. This is due to the migration enhancement of InAs during thegrowth the QDs. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quantum dot spin pure‐dephasing due to bulk magnons at low temperatures
Authors: Jacak Witold , Krasnyj Jurij , Jacak Lucjan 
Published: December 2008

AbstractWe demonstrate disappearance at 0 T = 0, and strong reduction at low temperatures, of pure‐dephasing of exciton spin located in a quantum dot (QD) embedded in a magnetic medium, e.g. in a diluted magnetic semiconductor. The off‐diagonal spin decoherence results due to hybridization of local QD exciton spin with magnons from surrounding crystal–we estimate the corresponding time‐scale and formulate a general rule for the scaling of dephasing time versus QD diameter derived within the Green function approach (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Energy transfer in hybrid CdSe quantum dots vs. labelled molecular chaperone systems by imaging microscopy
Authors: Tani Toshiro , Horiuchi Hiromi , Oda Masaru , Usukura Eiji , Sakai Hiroshi , Ohtaki Akashi , Yohda Masafumi 
Published: December 2008

AbstractResonant energy transfer in hybrid CdSe quantum dot (QD) conjugated with Cy5‐labelled molecular chaperone systems is observed with single molecule imaging technique. Photonic QDs are the core‐shell type nanocrystals covered with organic surfactants on the outermost surfaces, i.e. CdSe/ZnS/TOPO's, and prefoldin (PFD) is used as prototype molecular chaperons. PFD is a jellyfish‐shaped hexameric co‐chaperone of group II chaperonins, which recognize hydrophobic portion of denatured proteins and encapsulate them within its central cavity. So the CdSe/ZnS/TOPO QDs can also be captured be cause of its surface similarity to the denatured proteins. We have found one possible reaction pathway to get such artificial complex in aqueous solutions with keeping bioactivities of the proteins. Performance of the complex is evaluated by TIRF imaging microscopy. As the proteins are transparent in visible wavelength region, labeling dyes, Cy5, which also work as acceptors, are connected to detect their behaviors microscopically. Förster type energy transfer is observed from the QD donors to Cy5‐labeled PFD acceptors in single molecule level, which can be a distinct evidence for the complex formation. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)