bluuebunny/crossref_metadata_2025_split huggingface dataset:
Tailored Silica Macrocellular Foams: Combining Limited Coalescence‐Based Pickering Emulsion and Sol–Gel Process
Authors: Destribats Mathieu , Faure Benjamin , Birot Marc , Babot Odile , Schmitt Véronique , Backov Rénal 
Published: March 2012

AbstractSolid‐sate monolithic macrocellular foams are synthesized by mineralizing the continuous phase of oil‐in‐water Pickering emulsions, used as templates, with the sol–gel process. For the first time, taking advantage of the limited coalescence phenomenon occurring in emulsions stabilized by solid particles, concentrated emulsions with calibrated drop size are produced, leading to the synthesis of monolithic foams with nearly monodisperse macroscopic voids. Such a strategy allows independent tuning of the macrocellular void diameters from 20 to 800 μm and the diameter of the windows connecting adjacent cells. The obtained macrocellular foams also bear micro‐ and mesoporosity, leading to Brunauer, Emmet and Teller (BET) surface area values between 700 and 900 m2 g−1 with a good mesopores monodispersity.
Iridium‐Complex‐Modified Upconversion Nanophosphors for Effective LRET Detection of Cyanide Anions in Pure Water
Authors: Yao Liming , Zhou Jing , Liu Jinliang , Feng Wei , Li Fuyou 
Published: March 2012

AbstractBecause of the extreme toxicity of cyanide anions, a great deal of effort has been invested in developing probes that use colorimetric and fluorometric methods to detect them. To date, most of the current optical probes require the use of organic solvents or a mixture of organic solvents and water. Upconversion nanophosphors (UCNPs) can serve as excellent emitters as a result of their sharp emission peaks and simple control of the emission wavelength. Here, the fabrication of hybrid material composed of iridium complex and UCNPs to detect cyanide anions selectively in pure water is described. In addition to the colorimetric detection, the upconversion luminescence emission can serve as a detection signal based on an effective luminescent resonance energy transfer (LRET) process within the hybrid nanoparticles.
Revisiting the Structure of Graphene Oxide for Preparing New‐Style Graphene‐Based Ultraviolet Absorbers
Authors: He Wenhui , Lu Lehui 
Published: March 2012

AbstractDespite sustained effort over the years, the exploration of an effective strategy toward understanding the structure and properties of graphene oxide (GO) is still highly desirable. Herein, a facile route to revisit the structure of GO is demonstrated by elucidating its chemical‐conversion process solely in the presence of ammonia. Such a strategy can contribute to settling some arguments in recent models of GO, and also offers a prerequisite to identify critical components that can act as ultraviolet absorbers (UVAs) in resulting dispersions of nitrogen‐doped graphene sheets (NGSs). Inspired by this, for the first time, the performance of NGSs, serving as new‐style UVAs, is investigated through directly assessing the effect of NGSs on the photofastness of azo dyes (Food Black). These studies reveal that, distinct from the common understanding, the as‐prepared NGSs can dramatically enhance the photostability of Food Black under UV irradiation and exhibit greatly applied potential as a multifunctional UVA for new‐generation inkjet inks that can simultaneously integrate the advantages of dye‐based and pigment‐based inks.
Enhancement of Thermal Energy Transport Across Graphene/Graphite and Polymer Interfaces: A Molecular Dynamics Study
Authors: Luo Tengfei , Lloyd John R. 
Published: March 2012

AbstractUnderstanding thermal energy transport in polymeric nanocomposite materials is important to the engineering of polymer composites with better engineered heat transfer properties. Interfacial thermal resistance between the filling particles and the polymer matrices is a major bottleneck for the thermal conductivity improvement of polymer composite materials. Here, thermal energy transport in graphene/graphite‐polymer (paraffin wax‐C30H62) composite systems are systematically studied using molecular dynamics simulations. The influences of graphene size, interfacial bonding strength, and polymer density on the interfacial thermal transport are studied. According to the simulation results, approaches to improve interfacial thermal transport are proposed. Spectral analysis is performed to explore the mechanism of thermal transport. It is found that thermal energy transport across graphene/graphite‐polymer interfaces can be enhanced by increasing the polymer density and graphene size or forming covalent bonds between the graphite edges and polymer molecules. The results offer valuable guidance on improving thermal transport properties of polymeric nanocomposite.
Investigation of Optical and Structural Stability of Localized Surface Plasmon Mediated Light‐Emitting Diodes by Ag and Ag/SiO2 Nanoparticles
Authors: Jang Lee‐Woon , Jeon Dae‐Woo , Kim Myoung , Jeon Ju‐Won , Polyakov Alexander Y. , Ju Jin‐Woo , Lee Seung‐Jae , Baek Jong‐Hyeob , Yang Jin‐Kyu , Lee In‐Hwan 
Published: March 2012

AbstractLocalized surface plasmon (LSP) effects due to Ag and Ag/SiO2 nanoparticles (NPs) deposited on GaN/InGaN multiquantum well (MQW) light‐emitting diode (LED) structures are studied. The colloidal NPs are synthesized by a sol‐gel method and drop‐cased on the LED structures. The surface density of NPs its controlled by the concentration of the NP solution. Theoretical modeling is performed for the emission spectrum and the electric field distribution of LSP resonance for Ag/SiO2 NPs. Enhanced photoluminescence (PL) efficiency is observed in the LED structures and the amount of PL enhancement increases with increasing the surface density of Ag and Ag/SiO2 NPs. These effects are attributed to resonance coupling between the MQW and LSP in the NPs. It is also shown that the PL enhancement attainable with Ag NPs and Ag/SiO2 NPs is comparable, but the latter displays a much higher stability with respect to long‐term storage and annealing due to a barrier for NP agglomeration, Ag oxidation, and impurity diffusion provided by the SiO2 shell.
High‐Performance All‐Solid‐State Cells Fabricated With Silicon Electrodes
Authors: Phan Viet Phong , Pecquenard Brigitte , Le Cras Frédéric 
Published: March 2012

AbstractAll solid‐state thin‐film lithium microbatteries are a promising component able to fulfill most of the specific requirements to power autonomous microsystems. Nevertheless, metallic lithium, which is commonly used as the negative electrode in microbatteries, has a very low melting temperature (Tm = 181 °C) that appears to be incompatible with the solder‐reflow operation (maximum temperature Tmax ≈ 260 °C) usually used to connect electronic components. Silicon is a promising candidate to replace lithium in solder‐reflowable lithium‐ion cells due to its high volumetric capacity (834 μAh cm−2 μm−1 for Li15Si4) and its ability to reversibly insert lithium at a low potential. Nevertheless, it suffers from a large volumetric expansion during lithium insertion (280%), which is partly responsible for a rapid capacity fading when cycled in liquid electrolyte. In this study, all‐solid‐state Li/LiPONB/Si cells are prepared using physical vapor deposition (PVD) techniques. The cycle life and the coulombic efficiency are found to be excellent in these solid‐state cells with almost no loss during 1500 cycles. Despite the large volume expansion due to lithium insertion confirmed by scanning electron microscopy, no evidence of cracks is found in the film or at the electrode/electrolyte interface, even after 1500 cycles.
Highly Conductive Poly(3,4‐ethylenedioxythiophene):Poly (styrenesulfonate) Films Using 1‐Ethyl‐3‐methylimidazolium Tetracyanoborate Ionic Liquid
Authors: Badre Chantal , Marquant Ludovic , Alsayed Ahmed M. , Hough Lawrence A. 
Published: March 2012

AbstractHighly conductive poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) films are obtained using ionic liquids as additives. Upon adding 1‐ethyl‐3‐methylimidazolium tetracyanoborate (EMIM TCB) to the conducting polymer, the conductivity increases to 2084 S cm−1; this is attributed to the phase separation of PSS leading to a structural change in the film. A comparative study with 1‐butyl‐3‐methyl imidazolium tetrafluoroborate (BMIM BF4) shows that EMIM TCB gives higher conductivity and transmittance and can be regarded as one of the most promising additives for the preparation of indium tin oxide (ITO)‐free organic devices using PEDOT:PSS/EMIM TCB as electrodes.
Determining a definite diagnosis of primary immune thrombocytopenia by medical record review
Authors: Terrell Deirdra R. , Beebe Laura A. , Vesely Sara K. , Neas Barbara R. , Segal Jodi B. , George James N. 
Published: April 2012

AbstractThe objective of this study is to establish a method to identify patients with primary immune thrombocytopenia (ITP) utilizing administrative data from diverse data sources that would be appropriate for epidemiologic studies of ITP, regardless of patients' age and source of health care. Medical records of the Oklahoma University Medical Center, 1995–2004, were reviewed to document the accuracy of the administrative code ICD‐9‐CM 287.3 for identifying children and adults with ITP, using novel, explicit levels of evidence to identify patients with a definite diagnosis. The proportion of patients diagnosed by hematologists compared to non‐hematologists and the proportion of patients diagnosed as outpatients compared to inpatients were determined. For children, age <16 years, 323 outpatient medical records were reviewed; 225 adult outpatient medical records were reviewed. The positive predictive value for the administrative code for identifying patients with a definite diagnosis of ITP by a hematologist was 0.72 in children and 0.69 in adults. In 98% of children and 92% of adults seen as outpatients, the definite diagnosis of ITP was established by a hematologist. One hundred eighteen child and 141 adult inpatient medical records were reviewed. In 95% of children and 83% of adults, the definite diagnosis of ITP by a hematologist was established as an outpatient. This study confirmed the previously reported positive predictive value for the administrative code for identifying patients with ITP. Additionally, it was determined that analysis of hematologists' outpatient administrative codes identified most children and adults with ITP. Am. J. Hematol. 2012. © 2012 Wiley Periodicals, Inc.
Die Chemie der polycyclischen polyprenylierten Acylphloroglucine
Authors: Richard Jean‐Alexandre , Pouwer Rebecca H. , Chen David Y.‐K. 
Published: March 2012

AbstractMit ihren faszinierenden biologischen Profilen und erstaunlich komplexen Architekturen waren die polycyclischen polyprenylierten Acylphloroglucine (PPAPs) seit langem ein ertragreiches Gebiet für Organiker. Besonders das jüngste Aufkommen innovativer Synthesemethoden und ‐strategien, in Verbindung mit C‐C‐Bindungsbildungsreaktionen und der asymmetrischen Katalyse, hat dieses Gebiet stark wiederbelebt. Infolgedessen konnte nun Synthesen von PPAP‐Zielstrukturen realisiert werden, die früher unmöglich erschienen. Ziel dieses Aufsatzes ist die Darstellung kürzlich komplettierter Totalsynthesen von PPAPs und der bemerkenswerten Methoden, die für die Konstruktion des Bicyclo[3.3.1]‐Kernes dieser chemisch und biologisch faszinierenden Moleküle entwickelt wurden.
The Chemistry of the Polycyclic Polyprenylated Acylphloroglucinols
Authors: Richard Jean‐Alexandre , Pouwer Rebecca H. , Chen David Y.‐K. 
Published: March 2012

AbstractWith their fascinating biological profiles and stunningly complex molecular architectures, the polycyclic polyprenylated acylphloroglucinols (PPAPs) have long provided a fertile playing field for synthetic organic chemists. In particular, the recent advent of innovative synthetic methods and strategies together with CC bond‐forming reactions and asymmetric catalysis have revitalized this field tremendously. Consequently, PPAP targets which once seemed beyond reach have now been synthesized. This Review aims to highlight the recent achievements in the total synthesis of PPAPs, as well as notable methods developed for the construction of the bicyclo[3.3.1] core of these chemically and biologically intriguing molecules.
The interaction between poly(vinyl alcohol) and low‐molar‐mass poly(ethylene oxide)
Authors: Li Yangbo , Wu Wenqian , Lin Feng , Xiang Aiming 
Published: March 2012

AbstractThe interaction between poly(vinyl alcohol) (PVA) and low‐molar‐weight poly(ethylene oxide) (PEG) was studied. The thermal stability, glass transition temperature (Tg), crystallization, and melting behaviors were characterized as functions of content and molar mass of PEG. Dynamic mechanical thermal analysis revealed that PEG was compatible with PVA and provided plasticization effect to the latter. However, the plasticization was countered by the formation of hydrogen bonds between PEG molecules and PVA segments, which depressed the movement of PVA segments. At moderate contents of PEG, the hydrogen bonds were responsible for the increase in Tg, increase in crystallization heat, and decrease in crystallization rate. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Kinetic study of the aqueous free‐radical polymerization of 2‐acrylamido‐2‐methyl‐1‐propanesulfonic acid via an online proton nuclear magnetic resonance technique
Authors: Nadim E. , Bouhendi H. , Ziaee F. , Nouri A. 
Published: March 2012

AbstractThe free‐radical polymerization of 2‐acrylamido‐2‐methyl‐1‐propane sulfonic acid (AMPS) in aqueous media and in the presence of potassium persulfate (KPS) as a thermal initiator was studied. The 1H‐NMR method was applied to record the reaction data in online gain. The effects of the monomer and initiator concentrations and also the reaction temperature were studied. The order of reaction with respect to the monomer was much greater than unity (1.94). None of the three theories describing an order of reaction higher than unity could predict the AMPS polymerization mechanism in this study. So, a new mechanism is presented. It is suggested that initiation took place through the formation of a complex between the initiator and monomer, and termination occurred not only by a bimolecular reaction but also by a monomolecular reaction. The order with respect to KPS was 0.49; this was consistent with classical kinetic theory. The determined activation energy at the overall rate of reaction was 92.7 kJ mol−1 K−1. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Production of amorphous starch powders by solution spray drying
Authors: Niazi Muhammad B. K. , Broekhuis Antonius A. 
Published: March 2012

AbstractThe spray drying of starch/maltodextrin formulations was evaluated as a potential technology for the manufacturing of amorphous thermoplastic starches. Mixtures of starches with high to low amylose (Am)–amylopectin (Ap) ratios were spray‐dried from water‐based solutions and granular dispersions. The effects of the feed composition on the morphology and physical properties of the end product were investigated with the spray‐drying conditions kept constant. Powders obtained from the starch solutions were totally amorphous, and the particle size characteristics were not affected by the applied variations in composition. The particles obtained from the solution‐dried formulations were small, highly irregular, and shriveled, and the bulk densities were low. Independent of the Am/Ap ratio, the particles could easily be redissolved and showed low viscosities. The spray‐dried powders obtained from the starch–water dispersions very much retained the granular structure present in the native components. All showed viscosities, crystallinity patterns, gelatinization, and powder flow characteristics in line with expectations for Am/Ap‐based granular mixtures. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synergetic effect of sodium citrate and starch in the synthesis of silver nanoparticles
Authors: Kakkar Rita , Sherly E. D. , Madgula Kalpana , Devi D. Keerthi , Sreedhar B. 
Published: March 2012

AbstractSilver nanoparticles (AgNPs) were prepared under mild conditions by exploiting a combination of naturally abundant polymer starch and trisodium citrate as reducing agent and stabilizing agent. Optimization of the concentration of starch, citrate, pH, and reaction time showed significant influence on the size of the NPs. The obtained NPs were well characterized by UV–Vis, transmission electron microscopy, X‐ray diffraction, X‐ray photoelectron spectroscopy, and thermogravimetric analysis. The effect of varying proportions of citrate and starch and the order of their addition to the reaction mixture with respect to their role as reducing or, and stabilizing agents was also studied. The antibacterial activity of thus prepared NPs is being reported. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Synthesis and characterization of di‐polyester diamides
Authors: Stern Theodor 
Published: March 2012

AbstractA series of di‐polyester diamides was synthesized via a nucleophilic ring opening polymerization process. FTIR investigations revealed the spectral characteristics evidencing the newly formed chemical bonds as well as the changes in the relative intensity of the characteristic peaks, due to the increasing side‐block lengths of the different members of the series. 1H‐NMR analysis of the described materials confirmed the chemical structures seen by FTIR analysis. The side segment length of the different di‐polyester diamides was calculated from the integration ratios in the NMR spectra. The molecular weight results exhibited relatively small deviations from the stoichiometrically calculated values. All the members of the triblock series, with side blocks of up to 120 lactoyl units, were essentially amorphous and glassy at room temperature. The presence of two separate glass transitions indicated a segmented and microphase separated morphology. It was deducted that the amorphous nature of the relatively long poly(lactic acid) side blocks occurs due to the dominance of the hydrogen‐bonded central segment. Synthesis of a di‐polyester diamide containing a reduced number of hydrogen‐bond‐forming groups in the central segment yielded a partial side‐block crystallization. The di‐polyester diamide with 120 lactoyl unit‐long side blocks was eventually able to crystallize in solid state, following thermal treatment during thermal analysis. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Air permeability of electrospun polyacrylonitrile nanoweb
Authors: Abuzade Ramazan Ali , Zadhoush Ali , Gharehaghaji Ali Akbar 
Published: March 2012

AbstractUltrafine fibers were spun from polyacrylonitrile (PAN) solution inN,N‐dimethylformamide using a homemade electrospinning setup. Fibers with diameter ranging from 80 to 340 nm were obtained. Fiber size and fiber size distribution were investigated for various concentration, applied voltage, and tip‐to‐collector distance using image analysis. The diameters of the electrospun fibers increase when increasing the solution concentration and decrease slightly when increasing the voltage and needle tip‐to‐collector distance. Porosity and air permeability are vital properties in applications of electrospun nanofibrous structures. In this study, effects of process parameters on the porosity and air permeability of electrospun nanoweb were investigated as well. Results of statistical analysis showed that solution concentration and applied voltage have significant influences on pore diameters. It was concluded that nanofiber diameter played an important role on the diameter of pores formed by the intersections of nanofibers. A more realistic understanding of porosity was obtained and a quantitative relationship between nanoweb parameters and its air permeability was established by regression analysis. Two separate models were constructed for predicting air permeability in relation to process parameters. Optimization of electrospinning process for producing nanoweb with desirable air permeability is well achieved by these models. The models presented in this study are of high importance for their ability to predict the air permeability of PAN nanoweb both by process or structure parameters. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Comparing styrene butadiene rubber–clay nanocomposites prepared by melt intercalation and latex‐coagulation methods
Authors: Salehi M. , Razzaghi‐Kashani M. 
Published: March 2012

AbstractAmong different methods for preparation of rubber–clay nanocomposites, melt intercalation and latex‐coagulation methods are more practiced. In this study, dispersion of pristine nanoclay by the latex‐coagulation method and organically modified nanoclay by the melt‐intercalation method in styrene butadiene rubber were compared, based on the same amount of mineral clay in the composites. Dispersion of nanoclay was examined by X‐ray diffraction before and after vulcanization, and by atomic force microscopy after vulcanization. It was shown that final structure of nanoclay in the composites was intercalated by both methods, with better dispersion resulting from coagulation of latex over mixing in the melt state. Dynamic–mechanical–thermal analysis and tension tests were used to further assess dispersion and polymer–filler interactions. These tests confirmed better dispersion and larger interfacial area for pristine nanoclay in the latex‐coagulated rubber through observing lower peak loss factor, higher growth of stress in stretching, and lower elongation at break when compared with those for the nanocomposite prepared by the melt mixing. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Development and validation of a Measure of Criminal Social Identity within a sample of Polish recidivistic prisoners
Authors: Boduszek Daniel , Adamson Gary , Shevlin Mark , Hyland Philip 
Published: March 2012

ABSTRACTBackgroundSocial identity is a well‐established theoretical concept within psychological research; however, the role of criminal social identity has received far less research attention. One salient reason for the limited research relating to the concept of criminal social identity is the absence of a specific measure.AimTo develop and test the construct validity of a new measure of criminal social identity (MCSI) and to provide additional evidence relating to Cameron's three‐factor conceptualisation of social identity.MethodThe eight‐item MCSI was used to collect data from recidivists incarcerated in high‐security prison (N = 312) to assess criminal social identification. These data were subjected to confirmatory factor analysis.ResultsThree alternative models of criminal social identity were specified and tested in Mplus 6, and results revealed that the data were best explained by a three‐factor model of criminal social identity (cognitive centrality, in‐group affect and in‐group ties).ConclusionThe current study is important in terms of future research in criminology and psychology because the MCSI provides the first reliable MCSI, which was developed and validated on a relatively large recidivistic prison sample. Copyright © 2012 John Wiley & Sons, Ltd.