bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of the mechanical properties, crystallization, and enzymatic degradation behavior of poly(butylene succinate‐co‐ethyleneoxide‐co‐DL‐lactide) copolyesters
Authors: Tan Licheng , Chen Yiwang , Zhou Weihua , Nie Huarong , Ye Suwen 
Published: September 2011

AbstractA series of aliphatic biodegradable poly (butylene succinate‐co‐ethyleneoxide‐co‐DL‐lactide) copolyesters were synthesized by the polycondensation in the presence of dimethyl succinate, 1,4‐butanediol, poly(ethylene glycol), and DL‐oligo(lactic acid) (OLA). The composition, as well as the sequential structure of the copolyesters, was carefully investigated by 1H‐NMR. The crystallization behaviors, crystal structure, and spherulite morphology of the copolyesters were analyzed by differential scanning calorimetry, wide angle X‐ray diffraction, and polarizing optical microscopy, respectively. The results indicate that the sequence length of butylene succinate (BS) decreased as the OLA feed molar ratio increasing. The crystallization behavior of the copolyesters was influenced by the composition and sequence length of BS, which further tuned the mechanical properties of the copolyesters. The copolyesters formed the crystal structures and spherulites similar to those of PBS. The incorporation of more content of ethylene oxide (EO) units into the copolyesters led to the enhanced hydrophilicity. The more content of lactide units in the copolyesters facilitated the degradation in the presence of enzymes. The morphology of the copolyester films after degradation was also studied by the scanning electron microscopy. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis and characterization of chitosan/cloisite 30B film for controlled release of ofloxacin
Authors: Sahoo Debasish , Nayak P. L. 
Published: September 2011

AbstractIn this research program, chitosan film was prepared by blending chitosan with Cloisite 30 B at different concentrations 0 wt %, 1 wt %, and 2.5 wt %. The blends were characterized by Fourier transmission infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X‐ray diffraction (XRD) analysis. From the FTIR spectra the various groups present in chitosan/C 30 B blend were monitored. The homogeneity, morphology, and crystallinity of the blends were ascertained from SEM and XRD data, respectively. The most suitable form of blend was taken and used as a carrier for the controlled release of ofloxacin. The swelling studies have been carried out at different drug loading. Drug release kinetics was analyzed by plotting the cumulative release data versus time by fitting to an exponential equation which indicated the occurrence of non‐Fickian type of kinetics. The drug release was investigated at different pH medium and it was found that the drug release depends upon the pH medium as well as the nature of matrix. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis of a branched poly(phenylene ethylene) with bromomethyl groups as an organosoluble and functional parylene
Authors: Kobayashi Ataru , Sumi Kentaro , Konishi Gen‐ichi 
Published: September 2011

AbstractWe synthesized a branched poly(phenylene ethylene) (BPPE) with bromomethyl groups from 1,3,5‐tris(bromomethyl)benzene derivatives via the Wurtz coupling reaction. In the case of 1,3,5‐tris(bromomethyl)‐2,4,6‐trimethoxybenzene as a monomer, the obtained polymer (Mn = 6100, Mw/Mn = 1.9) had bromomethyl groups. The 1HNMR analysis showed that a very large number of unreacted bromomethyl groups (Ph‐CH2Br) remained in the BPPE; the reaction of this polymer with phenolic hydroxyl groups proceeded quantitatively. This suggested that BPPEs can be functionalized using unreacted bromomethyl groups, making them a very attractive starting point for the creation of functionalized BPPEs with further enhanced processability. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Analysis of tensile modulus of PP/nanoclay/CaCO3 ternary nanocomposite using composite theories
Authors: Zare Yasser , Garmabi Hamid 
Published: September 2011

AbstractThe tensile modulus of PP/nanoclay/CaCO3 hybrid ternary nanocomposite was analyzed using composite models. Rule of mixtures, inverse rule of mixtures, modified rule of mixtures (MROM), Guth, Paul, Counto, Hirsch, Halpin–Tsai, Takayanagi, and Kerner–Nielsen models were developed for three‐phase system containing two nanofillers. Among the studied models, inverse rule of mixtures, Hirsch, Halpin–Tsai, and Kerner–Nielsen models calculated the tensile modulus of PP/nanoclay/CaCO3 ternary nanocomposite successfully compared with others. Furthermore, the Kerner–Nielsen model was simplified to predict the tensile modulus by volume fractions of nanofillers. Also, Takayanagi model was modified for the current ternary system. The developed Takayanagi model can predict the tensile modulus using Young's modulus and volume fractions of matrix and nanofillers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Studies on the self‐assembly behavior of the hydrophobically associating polyacrylamide
Authors: Chen Hong , Ye Zhongbin , Han Lijuan , Luo Pingya 
Published: September 2011

AbstractContrasted with partially hydrolyzed polyacrylamide (HPAM), the self‐assembly behavior and microstructure of hydrophobically associating polyacrylamide (HAPAM) in aqueous solution have been studied by means of fluorescence spectrum, transmission electron microscopy (TEM), atomic force microscope (AFM), and apparent viscosity test in this article. The fluorescent probe analysis indicates that the HAPAM molecules will form associating aggregates in pure water. The results show that HAPAM can easily self‐assemble to form an aggregate by hydrophobic driving force in dilute aqueous solution. The association of hydrophobic groups of the HAPAM causes the formation of supermolecule, so there are associating aggregates formed at very low concentration and then leads to the formation of network at a higher concentration. TEM and AFM measurements show that a distinct network structure has been formed in 1000 mg L−1 of HAPAM solution, indicating the strong association of hydrophobic groups. These results are consistent with the viscosity measurement and reveal that the excellent viscosification of HAPAM is due to the association of hydrophobic groups in the aqueous solution. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Improving the magnetorheological properties of polyurethane magnetorheological elastomer through plasticization
Authors: Wu Jinkui , Gong Xinglong , Fan Yanceng , Xia Hesheng 
Published: September 2011

AbstractThe highly filled anisotropic polyurethane (PU) magnetorheological elastomers (MREs) were prepared through an in‐situ one‐step polycondensation process under a magnetic field. The carbonyl iron formed chain‐like structure, which was fixed in the PU matrix. The plasticizer diisooctyl phthalate (DOP) was incorporated into PU to soften the matrix and improve the MR effect. The influence of DOP on the microstructure and properties of PU MREs were investigated. The incorporation of DOP reduced the viscosity of the prepolymer and made the carbonyl iron align more easily in the PU matrix. The aligned chain‐like structure of carbonyl iron in PU greatly enhanced the thermal conductivity and the compressive properties of PU MREs. The incorporation of DOP reduced the modulus of PU MREs and the glass transition temperature of the soft segments of PU. But highly filled carbonyl iron and DOP led to a decrease in the thermal stability to some extent. The MR test showed that DOP plasticization significantly enhanced both absolute and relative MR effect simultaneously. With 70 wt% carbonyl iron and 15 wt% DOP (the weight ratio of Fe: PU: DOP is 70 : 15: 15), the absolute and relative MR effects of anisotropic PU MREs were ∼ 1.16 MPa and ∼ 386.7%, ∼ 3.5 and ∼ 58 times of the PU MRE without the plasticizer at the same iron content. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Novel poly‐bridged‐naphthalene with blue‐light‐emitting property via electropolymerization
Authors: Zhu Guang , Xu Jingkun , Yue Ruirui , Lu Baoyang , Hou Jian 
Published: September 2011

AbstractRelatively scant work was related to polynaphthalene (PN) and its derivatives because of the unique nonlinear optical properties which make PN and its derivatives owning potential applications in various domains. According to relevant studies, the pursuit for the synthesis of high quality PN films is a great challenge for the applications of PN. To achieve high quality polymer films, three bridged naphthalene derivatives were designed, and finally two crosslinked PN exhibiting space network were electrosynthesized, respectively, by direct anodic oxidation from 1,6‐bis(naphthalen‐2‐yloxy)hexane and 1,4‐bis((naphthalen‐2‐yloxy)methyl)benzene in mixed electrolyte of dichloromethane containing boron trifluoride diethyl etherate. Furthermore, as‐formed conducting films were characterized by cyclic voltammetry, spectroscopic analysis, thermal analysis, and scanning electron microscopy. And the series of characterizations indicated that films hold high stability and good blue‐light‐emitting property. Meanwhile, these polymer films were smooth, shiny, and flexible easily being processed into various shapes by conventional mechanical methods. Consequently, these high quality PN films will facilitate their potential applications as blue‐light‐emitting materials in organic light‐emitting diode. Because di(naphthalen‐2‐yl) terephthalate was difficult to electropolymerize, the effects of bridged spacers to polymerization were also discussed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Properties and structural characterization of oxide starch/chitosan/graphene oxide biodegradable nanocomposites
Authors: Ma Jun , Liu Changhua , Li Rui , Wang Jia 
Published: September 2011

AbstractNovel chitosan (CS)/oxidized starch (OST)/graphene oxide (GO) nanocomposites (COST/GO‐n) films are prepared in a casting and solvent evaporation method. Fourier transform infrared spectroscopy, X‐ray diffractions, atomic force microscopy, scanning electron microscopy, transmission electron microscopy, thermal gravimetric analysis, tensile testing, and moisture uptake are used to study the structure and properties of these nanocomposites. To indicate the effect of carboxyl groups of OST, some results of the properties of CS/starch/GO nanocomposite (CST/GO‐n) were selected for control experimentation. Compared with the control CST/GO‐n series, COST/GO‐n films, which have the same component ration showed higher tensile strength (σb) and lower elongation at break (εb). Additionally, in the COST/GO‐n series, the σb increased with an increase of GO loading. However, higher proportion of GO could result in aggregations of GO nanosheets and deterioration of the film properties. Compared with the COST/GO‐0, the values of σb and water resistance of the COST/GO‐4 containing 2.0 wt % of GO were improved by 57.7 and 20.1%, respectively. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Study of compostable behavior of jute nano fiber reinforced biocopolyester composites in aerobic compost environment
Authors: Maiti Sonakshi , Ray Dipa , Mitra Debarati , Misra Manjusri 
Published: September 2011

AbstractJute nano fiber (JNF) reinforced biocopolyester‐based composite sheets were prepared with 2% and 10 wt % filler loading and compostability tests were performed in simulated aerobic compost environment at ambient temperature for a period of 50 days. Weight loss study revealed that the incorporation of JNF enhanced the rate of degradation significantly. The unreinforced sample exhibited a steady loss in weight, whereas, the JNF reinforced samples showed three phase degradation. They had a steady weight loss up to 30 days followed by a plateau zone between 30 and 40 days and after that, there was again an increase in weight loss up to 50 days. The biodegraded samples were investigated for their change in molecular weight by Gel Permeation Chromatography (GPC). The change in structure was examined by Differential Scanning Calorimetry (DSC) and morphological change was observed by Scanning Electron Microscopy (SEM). Molecular weight study revealed the fact that Biocopolyester molecules had a significant breakdown in chain length during melt mixing with 10 wt % JNF, which was much less predominant in 2 wt % JNF loaded composites. Such a decrease in chain length and presence of 10 wt % JNF might have facilitated the biodegradation process resulting in highest weight loss. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Frequency response analysis of nonisothermal film blowing process using transient simulations
Authors: Kim Hyung Min , Sung Lee Joo , Jung Hyun Wook , Hyun Jae Chun 
Published: September 2011

AbstractFrequency response of the nonisothermal viscoelastic film blowing process to the ongoing sinusoidal disturbances has been investigated using transient simulation techniques. Of the many state variables exhibiting resonant peaks with the input frequency, amplitude ratio of the film cross‐sectional area at the freezeline height has been used as an indicator of the process sensitivity. The effects of operating conditions and viscoelasticity on the sensitivity have been scrutinized around the middle point of three multiple steady states under the given conditions. The sensitivity results have been interpreted through their correlation with results from linear stability analysis. Increasing draw ratio generally makes the system more sensitive to sinusoidal disturbances, whereas the cooling induces more sensitive or less sensitive system, according to the location of a steady state. Also, the viscoelasticity makes the system of extensional thickening fluids more sensitive at low Deborah number and less sensitive at high Deborah number. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Evaluation of Anti‐inflammatory, Anti‐nociceptive, and Anti‐ulcerogenic Activities of Novel Synthesized Thiazolyl and Pyrrolyl Steroids
Authors: Mohareb Rafat M. , Elmegeed Gamal A. , Baiuomy Ayman R. , Eskander Emad F. , William Marian G. 
Published: September 2011

AbstractDeveloping new therapeutic agents that can overcome gastrointestinal injury and at the same time could lead to an enhanced anti‐inflammatory effect becomes an urgent need for inflammation patients. Thiazolyl and pyrrolyl steroids were synthesized via straight forward and efficient methods and their structures were established based on their correct elemental analysis and compatible IR, 1H‐NMR, 13C‐NMR, and mass spectral data. The dihydrothiazolyl‐hydrazonoprogesterone 12 and the aminopyrrolylprogesterone 16a showed anti‐inflammatory, antinociceptive, and anti‐ulcerogenic activity with various intensities. Edema were significantly reduced by both doses of tested compounds (25 and 50 mg/kg) at 2, 3, and 4 h post‐carrageenan. The high dose of compound 16a was the most effective in alleviating thermal pain. Gastric mucosal lesions, caused in the rats by the administration of ethanol or indomethacin (IND), were significantly inhibited by each of the two tested compounds. These results provide a unique opportunity to develop new anti‐inflammatory drugs which devoid the ulcerogenic liabilities associated with currently marketed drugs.
Emphasizing social features in information portals: Effects on new member engagement
Authors: Sharma Nikhil , Butler Brian S. , Irwin Jeannie , Spallek Heiko 
Published: September 2011

AbstractMany information portals are adding social features with hopes of enhancing the overall user experience. Invitations to join and welcome pages that highlight these social features are expected to encourage use and participation. While this approach is widespread and seems plausible, the effect of providing and highlighting social features remains to be tested. We studied the effects of emphasizing social features on users' response to invitations, their decisions to join, their willingness to provide profile information, and their engagement with the portal's social features. The results of a quasi‐experiment found no significant effect of social emphasis in invitations on receivers' responsiveness. However, users receiving invitations highlighting social benefits were less likely to join the portal and provide profile information. Social emphasis in the initial welcome page for the site also was found to have a significant effect on whether individuals joined the portal, how much profile information they provided and shared, and how much they engaged with social features on the site. Unexpectedly, users who were welcomed in a social manner were less likely to join and provided less profile information; they also were less likely to engage with social features of the portal. This suggests that even in online contexts where social activity is an increasingly common feature, highlighting the presence of social features may not always be the optimal presentation strategy.
Metal‐Free 1,5‐Regioselective Azide–Alkyne [3+2]‐Cycloaddition
Authors: Kloss Florian , Köhn Uwe , Jahn Burkhard O. , Hager Martin D. , Görls Helmar , Schubert Ulrich S. 
Published: September 2011

Abstract[3+2]‐cycloaddition reactions of aromatic azides and silylated alkynes in aqueous media yield 1,5‐disubstituted‐4‐(trimethyl‐silyl)‐1H‐1,2,3‐triazoles. The formation of the 1,5‐isomer is highly favored in this metal‐free cycloaddition, which could be proven by 1D selective NOESY and X‐ray investigations. Additionally, DFT calculations corroborate the outstanding favoritism regarding the 1,5‐isomer. The described method provides a simple alternative protocol to metal‐catalyzed “click chemistry” procedures, widening the scope for regioselective heavy‐metal‐free synthetic applications.
Click Chemistry: 1,2,3‐Triazoles as Pharmacophores
Authors: Agalave Sandip G. , Maujan Suleman R. , Pore Vandana S. 
Published: September 2011

AbstractThe copper(I)‐catalyzed 1,2,3‐triazole‐forming reaction between azides and terminal alkynes has become the gold standard of ‘click chemistry’ due to its reliability, specificity, and biocompatibility. Applications of click chemistry are increasingly found in all aspects of drug discovery; they range from lead finding through combinatorial chemistry and target‐templated in vitro chemistry, to proteomics and DNA research by using bioconjugation reactions. The triazole products are more than just passive linkers; they readily associate with biological targets, through hydrogen‐bonding and dipole interactions. The present review will focus mainly on the recent literature for applications of this reaction in the field of medicinal chemistry, in particular on use of the 1,2,3‐triazole moiety as pharmacophore.
Genetically inbred Balb/c mice differ from outbred Swiss Webster mice on discrete measures of sociability: relevance to a genetic mouse model of autism spectrum disorders
Authors: Jacome Luis F. , Burket Jessica A. , Herndon Amy L. , Deutsch Stephen I. 
Published: September 2011

AbstractThe Balb/c mouse is proposed as a model of human disorders with prominent deficits of sociability, such as autism spectrum disorders (ASDs) that may involve pathophysiological disruption of NMDA receptor‐mediated neurotransmission. A standard procedure was used to measure sociability in 8‐week‐old male genetically inbred Balb/c and outbred Swiss Webster mice. Moreover, because impaired sociability may influence the social behavior of stimulus mice, we also measured the proportion of total episodes of social approach made by the stimulus mouse while test and stimulus mice were allowed to interact freely. Three raters with good inter‐rater agreement evaluated operationally defined measures of sociability chosen because of their descriptive similarity to deficits of social behavior reported in persons with ASDs. The data support previous reports that the Balb/c mouse is a genetic mouse model of impaired sociability. The data also show that the behavior of the social stimulus mouse is influenced by the impaired sociability of the Balb/c strain. Interestingly, operationally defined measures of sociability did not necessarily correlate with each other within mouse strain and the profile of correlated measures differed between strains. Finally, “stereotypic” behaviors (i.e. rearing, grooming and wall climbing) recorded during the session of free interaction between the test and social stimulus mice were more intensely displayed by Swiss Webster than Balb/c mice, suggesting that the domains of sociability and “restricted repetitive and stereotyped patterns of behavior” are independent of each other in the Balb/c strain. Autism Res 2011,4:393–400. © 2011 International Society for Autism Research, Wiley Periodicals, Inc.
Impact of distributed storage and pre‐processing on Miscanthus production and provision systems
Authors: Shastri Yogendra N. , Rodriguez Luis F. , Hansen Alan C. , Ting K.C. 
Published: September 2011

AbstractDistributed storage and pre‐processing of biomass feedstock at satellite storage locations (storage depots) has been proposed in literature to reduce costs and improve efficiency of the supply system. The performance of such a system, however, has not yet been rigorously quantified and compared with conventional alternatives. This work presents such an analysis using the BioFeed optimization model. BioFeed is a system‐level model that optimizes the important feedstock production activities and determines the optimal system configuration on a regional basis. The BioFeed model was first modified to enable modeling of mechanical pre‐processing, such as pelletization and grinding, at the input or the output of storage facilities, which can be mandatory or optional. The model was used to study different Miscanthus production scenarios in southern Illinois. The results showed that making storage pre‐processing mandatory increased the total cost by up to 16–53% as compared to the base case. However, it reduced the farmers' share of the total cost by up to 13–39%. The exact values depended on the particular pre‐processing technology and scenario modeled. The most cost‐effective system consisted of a combination of pre‐processing on the farms as well as at the storage facilities. The study recommended that biomass output from a hammer mill should be the biorefinery delivery specification; the hammer mills should be installed at the input of the storage facilities, but pre‐processing at the storage facility should be optional. This led to the minimum total cost of 46.4 $ Mg‐1. © 2011 Society of Chemical Industry and John Wiley & Sons, Ltd
Caught in the act: Rapid, symbiont‐driven evolution
Authors: White Jennifer A. 
Published: September 2011

AbstractFacultative bacterial endosymbionts can transfer horizontally among lineages of their arthropod hosts, providing the recipient with a suite of traits that can lead to rapid evolutionary response, as has been recently demonstrated. But how common is symbiont‐driven evolution? Evidence suggests that successful symbiont transfers are most likely within a species or among closely related species, although more distant transfers have occurred over evolutionary history. Symbiont‐driven evolution need not be a function of a recent horizontal transfer, however. Many endosymbionts infect only a small proportion of a host population, but could quickly increase in frequency under favorable selection regimes. Some host species appear to accumulate a diversity of facultative endosymbionts, and it is among these species that symbiont‐driven evolution should be most prevalent. It remains to be determined how frequently symbionts enable rapid evolutionary response by their hosts, but substantial ecological effects are a likely consequence whenever it does occur.