bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surface‐Protected Etching of Mesoporous Oxide Shells for the Stabilization of Metal Nanocatalysts
Authors: Zhang Qiao , Lee Ilkeun , Ge Jianping , Zaera Francisco , Yin Yadong 
Published: June 2010

AbstractNanoparticles of transition metals, particularly noble metals, are widely used in catalysis. However, enhancing their stability during catalytic reactions has been a challenge that has limited the full use of the benefits associated with their small size. In this Feature Article, a general “encapsulation and etching” strategy for the fabrication of nanocatalyst systems is introduced in which catalyst nanoparticles are protected within porous shells. The novelty of this approach lies in the use of chemical etching to assist the creation of mesopores in a protective oxide shell to promote efficient mass transfer to encapsulated metal nanoparticles. The etching process allows for the direct transformation of dense silica coatings into porous shells so that chemical species can reach the catalyst surface to participate in reactions while the shells act as physical barriers against aggregation of the catalyst particles. By using the surface‐protected etching process, both yolk–shell and core–satellite type nanoreactors are synthesized and their utilization in liquid‐ and gas‐phase catalysis is demonstrated. The thermal and chemical stability of the metallic cores during catalytic reactions is also investigated, and further work is carried out to enhance recyclability via the introduction of superparamagnetic components into the nanoreactor framework.
The studies on the motion of the sine‐Gordon kink on a curved surface
Authors: Dobrowolski T. 
Published: June 2010

AbstractThe numerical studies of the kink motion on a curved manifold were performed. Examples of the curved surfaces are considered in detail. Enlarging the kink width in curved regions of the surface and reduction of its speed is confirmed. Reflection of the kink front from the large curvature areas is observed. The influence of the curvature on the speed of the Vachaspati waves is also observed.
Shape‐Persistent Organic Cage Compounds by Dynamic Covalent Bond Formation
Authors: Mastalerz Michael 
Published: June 2010

AbstractOne area of supramolecular chemistry involves the synthesis of discrete three‐dimensional molecules or supramolecular aggregates through the coordination of metals. This field also concerns the chemistry of supramolecular cage compounds constructed through the use of such coordination bonds. To date, there exists a broad variety of supramolecular cage compounds; however, analogous organic cage compounds formed with only covalent bonds are relatively rare. Recent progress in this field can be attributed to important advances, not least the application of dynamic covalent chemistry. This concept makes it possible to start from readily available precursors, and in general allows the synthesis of cage compounds in fewer steps and usually higher yields.
Thermal decomposition of cellulose/synthetic polymer blends containing grafted products. V. Cellulose/polystyrene blends
Authors: Nishioka Noboru , Funakoshi Miyuki , Inamoto Kohji , Uno Masakuni , Ueda Akira 
Published: June 2010

AbstractHomogeneous grafting of styrene onto cellulose was carried out in a dimethylacetamide/lithium chloride solvent system. The grafted products were added to cellulose/polystyrene (PS) blends as compatibilizers. The thermal decomposition behavior of the blends was investigated by thermogravimetry. The thermal stability of the blends decreased with an increase in grafted product content. The crystallinity of the blends decreased with grafted product content. The microphase‐separated structures of the blends became finer with grafted product content. The glass transition temperatures for cellulose and PS in the blends were lowered with grafted product content. Differences in thermal decomposition behavior of the blends were correlated with compatibility. Thermogravimetry was effective for compatibility estimation in cellulose/PS blends containing grafted products. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Characteristics of soy protein isolate‐montmorillonite composite films
Authors: Lee Jung‐Eun , Kim Ki Myong 
Published: June 2010

AbstractSoy protein isolate/montmorillonite (SPI/MMT) nanocomposite films were prepared in which MMT was used as a nanofiller at 0, 3, 6, 9, 12, and 15 wt % relative to SPI dry weight. Effects of MMT on film properties including tensile strength, elongation at break, total soluble matter, water vapor permeability, and oxygen permeability were assessed. X‐ray diffraction patterns were determined, and morphologies of SPI and the SPI‐MMT composite films were visualized by scanning electron microscopy. Mechanical and barrier properties were improved by evidenced increases in tensile strength and modulus, and decreases in permeability to water vapor and oxygen. MMT concentrations of 3%–12% were optimal for improving functional properties of the composite films. X‐ray diffraction and scanning electron microscopy examinations revealed the formation of an intercalated and exfoliated structure on the addition of MMT into the SPI matrix. We conclude that intercalated and exfoliated MMT silicates enhance mechanical and barrier properties of SPI films. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Effect of styrene–ethylene–butadiene–styrene and its synergetic effect with ethylene vinyl acetate on the mechanical, thermal, dielectric, and water‐treeing behaviors of crosslinked polyethylene
Authors: Ma Zhisen , Jiang Pingkai , Wang Lichun , Yang Junsheng 
Published: June 2010

AbstractIn this study, we investigated the effect of an aromatic polymer, styrene–ethylene–butadiene–styrene (SEBS), on the water‐tree resistance of crosslinked polyethylene (XLPE), and the synergetic effect of SEBS and ethylene vinyl acetate (EVA) was also investigated. The XLPE/SEBS and XLPE/SEBS/EVA samples were characterized by means of differential scanning calorimetry, scanning electron microscopy, mechanical measurements, and an accelerated water‐treeing experiment, and the obtained results clearly show the relevant influence of SEBS and EVA, and as expected, the addition of SEBS and EVA was found to synergistically influence the water‐tree resistance of XLPE more positively in comparison with that without the addition of EVA. In addition, it also indicated that the blends possessed excellent dielectric behaviors, such as the dielectric constant and dissipation factor. The crystallization of the blends decreased with increasing SEBS content and addition of EVA. However, the melting temperature of the blends increased with the addition of SEBS and EVA, but the melting temperature of the blends decreased with increasing SEBS content. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Controlled release of chlorpheniramine maleate through IPN beads of sodium alginate‐g‐methylmethacrylate
Authors: Lakshmi Narayana Reddy C. , Swamy B. Yerri , Prasad C. Venkata , Subha M.C.S. , Rao K. Chowdoji 
Published: June 2010

AbstractControlled release of chlorpheniramine maleate drug, through sodium alginate‐g‐methylmethacrylate (NaAlg‐g‐MMA) interpenetrating polymeric network beads, has been investigated. Beads were prepared by precipitating the viscous solution of NaAlg‐g‐MMA in acetone followed by cross‐linking with glutaraldehyde. The beads were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). Different formulations of beads were developed by varying amounts of MMA, cross‐linking agent, and drug concentration. DSC thermograms of chlorpheniramine maleate drug‐loaded NaAlg‐g‐MMA beads confirmed the molecular level distribution of drug in the polymer matrix. FTIR of beads confirm the grafting and cross‐linking, SEM of the beads suggested the formation of spherical particles. Swelling experiments on the beads provided an important information on drug diffusion properties. Release data have been analyzed using an empirical equation to understand the nature of transport of drug containing solution through the polymeric matrices. The controlled release characteristics of the matrices for chlorpheniramine maleate was investigated in pH 7.4 media. Drug was released in a controlled manner upto 12 h. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Synthesis and characterization of AB‐type copolymers poly(L‐lactide)‐block‐poly(methyl methacrylate) via a convenient route combining ROP and ATRP from a dual initiator
Authors: Wang Wei‐Wei , Ren Wu‐Yang , Jiang Long , Dan Yi 
Published: June 2010

AbstractDiblock copolymers of poly(L‐lactide)‐block‐poly(methyl methacrylate) (PLLA‐b‐PMMA) were synthesized through a sequential two‐step strategy, which combines ring‐opening polymerization (ROP) and atom transfer radical polymerization (ATRP), using a bifunctional initiator, 2,2,2‐trichloroethanol. The trichloro‐terminated poly(L‐lactide) (PLLA‐Cl) with high molecular weight (Mn,GPC = 1–12 × 104 g/mol) was presynthesized through bulk ROP of L‐lactide (L‐LA), initiated by the hydroxyl group of the double‐headed initiator, with tin(II) octoate (Sn(Oct)2) as catalyst. The second segment of the block copolymer was synthesized by the ATRP of methyl methacrylate (MMA), with PLLA‐Cl as macroinitiator and CuCl/N,N,N′,N″,N″‐pentamethyldiethylenetriamine (PMDETA) as catalyst, and dimethyl sulfoxide (DMSO) was chosen as reaction medium due to the poor solubility of the macroinitiator in conventional solvents at the reaction temperature. The trichloroethoxyl terminal group of the macroinitiator was confirmed by Fourier transform infrared spectroscopy (FTIR) and 1H‐NMR spectroscopy. The comprehensive results from GPC, FTIR, 1H‐NMR analysis indicate that diblock copolymers PLLA‐b‐PMMA (Mn,GPC = 5–13 × 104 g/mol) with desired molecular composition were obtained by changing the molar ratio of monomer/initiator. DSC, XRD, and TG analyses establish that the crystallization of copolymers is inhibited with the introduction of PMMA segment, which will be beneficial to ameliorating the brittleness, and furthermore, to improving the thermal performance. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Preparation and characterization of epoxy/kaolinite nanocomposites
Authors: Xia Xinnian , Zeng Xiaoliang , Liu Jia , Xu Weijian 
Published: June 2010

AbstractEpoxy/kaolinite nanocomposites were prepared by adding the organically modified layered kaolinite to an epoxy resin [biphenyl phenol novolac epoxy resin (BPNE)] with 4,4′‐diamino biphenyl sulfone (DDS) as a curing agent. The dispersion state of the kaolinite within crosslinked epoxy‐resin matrix was examined by X‐ray diffraction (XRD) and transmission electron micrograph (TEM). The effects of kaolinite on thermal properties were investigated and discussed by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Experimental results show that BPNE/kaolinite nanocomposites exhibit improved thermal than pure BPNE. When the kaolinite content is 5 wt %, the BPNE/kaolinite nanocomposites show the best thermal properties. These results indicate that nanocomposition is an efficient and convenient method to improve the thermal properties of BPNE. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Rapid and Slow Generation of 1‐Trifluoromethylvinyllithium: Syntheses and Applications of CF3‐Containing Allylic Alcohols, Allylic Amines, and Vinyl Ketones
Authors: Nadano Ryo , Fuchibe Kohei , Ikeda Masahiro , Takahashi Hiroki , Ichikawa Junji 
Published: June 2010

Abstract1‐(Trifluoromethyl)vinylation is accomplished in two protocols by the in situ generation of thermally unstable 3,3,3‐trifluoroprop‐1‐en‐2‐yllithium (1): 1) a rapid lithium–halogen‐exchange reaction of 2‐bromo‐3,3,3‐trifluoroprop‐1‐ene (2) takes effect with sec‐BuLi at −105 °C to generate vinyllithium 1, which reacts with more reactive electrophiles, such as aldehydes and N‐tosylimines before its decomposition, to afford 2‐(trifluoromethyl)allyl alcohols and N‐[2‐(trifluoromethyl)allyl] sulfoamides in good yield; 2) treatment of 2 with nBuLi at −100 °C causes a slow lithium–halogen exchange of 2, which gives rise to a mixture of 1 and nBuLi. Vinyllithium 1 is preferentially trapped with less reactive electrophiles, such as N,N‐dimethylamides in the presence of BF3⋅OEt2, to afford 1‐(trifluoromethyl)vinyl ketones in good yield. Versatility of the products toward syntheses of CF3‐containing ring‐fused cyclopentenones is also demonstrated by the Pauson–Khand reaction and the Nazarov cyclization.
Output feedback control for stochastic nonholonomic systems with growth rate restriction
Authors: Liu Yun‐Long , Wu Yu‐Qiang 
Published: June 2010

AbstractThe output feedback stabilization problem is investigated in this paper for nonholonomic systems with stochastic disturbances. The objective is to design global asymptotical stabilization output feedback controllers in probability for systems by using discontinuous control. A switching control strategy based on the output measurement of the first subsystem is employed to achieve almost global asymptotical stabilization in probability. The input‐state scaling technique is introduced for discontinuous feedback and a high gain observer is introduced for states estimate. Thereby, the integrator backstepping technique is applied to the design of the controllers. The output feedback global asymptotical stabilization in probability is realized. An example is given to show the effectiveness of the proposed scheme.Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Delay‐dependent robust stabilization for uncertain singular systems with multiple time‐varying state delays
Authors: Liu Lili , Zhang Qingling , Du Zhaoping 
Published: June 2010

AbstractIn this note, the problem of delay‐dependent robust stabilization for singular systems with multiple time‐varying state delays has been investigated, and the problem is solved via state feedback controller in terms of a linear matrix inequality technique. Numerical examples are given to show the validity of the proposed method.Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
A chromospheric dark‐cored fibril in Ca II IR spectra
Authors: Beck C. , Tritschler A. , Wöger F. 
Published: June 2010

AbstractWe investigate the thermodynamical and magnetic properties of a “dark‐cored” fibril seen in the chromospheric Ca II IR line at 854.2 nm to determine the physical process behind its appearance. We analyse a time series of spectropolarimetric observations obtained in the Ca II IR line at 854.2 nm and the photospheric Fe I line at 630.25 nm. We simultaneously invert the spectra in both wavelength ranges with the SIR code to obtain the temperature and velocity stratification with height in the solar atmosphere and the magnetic field properties in the photosphere. The structure can be clearly traced in the line‐of‐sight (LOS) velocity and the temperature maps. It connects from a small pore with kG fields to a region with lower field strength. The flow velocity and the temperature indicate that the height of the structure increases with increasing distance from the inner footpoint. The Stokes V signal of 854.2 nm shows a Doppler‐shifted polarization signal with the same displacement as in the intensity profile, indicating that the supersonic flow seen in the LOS velocity is located within magnetized plasma. We conclude that the chromospheric dark‐cored fibril traces a siphon flow along magnetic field lines, driven by the gas pressure difference caused by the higher magnetic field strength at the inner footpoint. We suggest that fast flows guided by the magnetic field lead to the appearance of “dark‐cored” fibrils in intensity images. Although the observations included the determination of the polarization signal in the chromospheric Ca II IR line, the signal could not be analysed quantitatively due to the low S/N. Chromospheric polarimetry will thus require telescopes of larger aperture able to collect a sufficient number of photons for a reliable determination of polarization in deep and only weakly polarized spectral lines (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The origin of cutoff frequencies for torsional tube waves propagating in the solar atmosphere
Authors: Hammer R. , Musielak Z.E. , Routh S. 
Published: June 2010

AbstractTorsional waves supported by magnetic flux tubes have long been thought to bear a high potential for supplying energy and momentum to the upper solar atmosphere, thereby contributing to its heating and to the driving of dynamic events like spicules. This hope rested on the belief that their propagation is not impeded by cutoff restrictions, unlike longitudinal and kink waves. We point out that this applies only to thin, isothermal tubes. When they widen in the chromosphere, and as a result of temperature gradients, cutoff restrictions arise. We compare them to recent observational reports of such waves and of vortex motions and find that their long period components are already affected by cutoff restrictions. An observational strategy is proposed that should permit the derivation of better information on vortex flows from off‐center observations with next generation telescopes (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Double‐pass spectro‐imaging: TUNIS
Authors: López Ariste A. , Le Men C. , Gelly B. , Asensio Ramos A. 
Published: June 2010

AbstractWe present TUNIS, a double‐pass spectro‐imager built in THEMIS as a proof‐of‐concept for EST. Basic concepts and selected first results are shown. We introduce the concept of a Hadamard spectral mask as a proposition to move forward from the present implementation of a single‐wavelength per image pixel to a more general one of multiplexed spectral information that improves the temporal coherence of the spectral measurement (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Fast computation of 2D transfer functions from adaptive optics data
Authors: Wöger F. 
Published: June 2010

AbstractThe use of atmospheric transfer functions is common in image reconstruction techniques such as speckle interferometry to calibrate the Fourier amplitudes of the reconstructed images. Thus, an accurate model is needed to ensure proper photometry in the reconstruction. The situation complicates when adaptive optics (AO) are used during data acquisition. I propose a novel technique to derive two‐dimensional transfer functions from data collected using AO simultaneously with the observations. The technique is capable to compute the relevant transfer functions within a short time for the prevailing atmospheric conditions and AO performance during data acquisition (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Automated lab‐scale production of PVA/PEG‐enzyme immobilisates
Authors: Bieler Nora C. , Ansorge‐Schumacher Marion B. , Greiner Lasse 
Published: June 2010

AbstractEntrapment of biocatalysts by cryogelation is a gentle method to extend the scope of biocatalysis. To foster the use of this versatile method we devised an automated injector for the production of PVA/PEG beads. The device consists of a thermostated reservoir connected to a programmable injector nozzle and an agitated receiving bath for the droplets. This lab‐scale production unit yields up to 1500 beads with immobilized enzyme per minute with a narrow size distribution and good roundness.
FPGA‐based educational platform for real‐time image processing experiments
Authors: Ramirez‐Cortes Juan Manuel , Gomez‐Gil Pilar , Alarcon‐Aquino Vicente , Martinez‐Carballido Jorge , Morales‐Flores Emmanuel 
Published: June 2010

AbstractIn this paper, an implementation of an educational platform for real‐time linear and morphological image filtering using a FPGA NexysII, Xilinx®, Spartan 3E, is described. The system is connected to a USB port of a personal computer, which in that way form a powerful and low‐cost design station for educational purposes. The FPGA‐based system is accessed through a MATLAB graphical user interface, which handles the communication setup and data transfer. The system allows the students to perform comparisons between results obtained from MATLAB simulations and FPGA‐based real‐time processing. Concluding remarks derived from course evaluations and lab reports are presented. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 193–201, 2013
Enzymes Responsible for the Conversion of Nα‐[(Benzyloxy)carbonyl]‐D‐lysine to Nα‐[(Benzyloxy)carbonyl]‐D‐aminoadipic Acid by Rhodococcus sp. AIU Z‐35‐1
Authors: Isobe Kimiyasu , Fukuda Nahoko , Nagasawa Shouko , Saitou Kaoru 
Published: June 2010

AbstractThe enzymes responsible for the conversion of Nα‐[(benzyloxy)carbonyl]‐D‐lysine (Nα‐Z‐D‐lysine) to Nα‐Z‐D‐aminoadipic acid (Nα‐Z‐D‐AAA) by Rhodococcus sp. AIU Z‐35‐1 were identified. Nα‐Z‐D‐Lysine was first converted to Nα‐Z‐D‐aminoadipic δ‐semialdehyde (Nα‐Z‐D‐AASA) by D‐specific amino acid deaminase, whereas Nα‐Z‐L‐lysine was converted to Nα‐Z‐L‐AASA by L‐specific amino acid oxidase. The resulting Nα‐Z‐D‐AASA was then converted to Nα‐Z‐D‐AAA by the same aldehyde dehydrogenase that is responsible for Nα‐Z‐L‐AASA oxidation. The product amount of the D‐specific amino acid deaminase reached the maximum at one day of cultivation in the L‐lysine medium. The aldehyde dehydrogenase reached the maximum at three days of cultivation.
New Biological Functions and Applications of High‐Molecular‐Mass Poly‐γ‐glutamic Acid
Authors: Poo Haryoung , Park Chung , Kwak Mi‐Sun , Choi Doo‐Yeol , Hong Seung‐Pyo , Lee Il‐Han , Lim Yong Taik , Choi Young Ki , Bae Sun‐Ryang , Uyama Hiroshi , Kim Chul‐Joong , Sung Moon‐Hee 
Published: June 2010

AbstractUltra‐high‐molecular‐weight poly‐γ‐glutamic acid (γ‐PGA) is a most promising biodegradable polymer that is produced by Bacillus subtilis (chungkookjang). Attractive properties of γ‐PGA are that it is water soluble, anionic, biodegradable, and edible. Development of γ‐PGA has pursued in terms of cosmetics/skin care, bone care, nanoparticle for drug delivery system, hydrogel, and so on. Very recently, our research has shown that γ‐PGA can be used as an immune‐stimulating agent, especially at high molecular weight. This review presents the synthesis and production of high‐molecular‐weight γ‐PGA and its various applications in industrial fields.
Modeling the Enolization of Succinimide Derivatives, a Key Step of Racemization of Aspartic Acid Residues: Importance of a Two‐H2O Mechanism
Authors: Takahashi Ohgi , Kobayashi Kana , Oda Akifumi 
Published: June 2010

AbstractRacemization of aspartic acid residues in peptides and proteins is assumed to proceed via succinimide intermediates. An enolization of the succinimide intermediate is required for the racemization to occur. In this study, we modeled the enolization step by density‐functional theory (DFT) calculations (B3LYP/6‐31+G**), using two model compounds, N‐methylsuccinimide (1) and its formylamino derivarive 2. Three mechanisms were investigated for 1, i.e., the direct mechanism without active participation of H2O molecules, and one‐H2O and two‐H2O mechanisms, in which one or two H2O molecules actively participate in the reaction. We found that the two‐H2O mechanism was the most favorable with an activation barrier of 37 kcal mol−1. In the two‐H2O mechanism, a concerted bond reorganization involving a triple H‐atom transfer occurred in an eight‐membered cyclic structure formed between the imide and two H2O molecules. For 2, we investigated only the two‐H2O mechanism and found that the activation barrier was lowered to 31 kcal mol−1 due to an H‐bond between the CO O‐atom of the formylamino group (‘the neighboring residue’) and one of the H2O molecules. Our results suggest that, in proteins, the Asp racemization is severely controlled by the accessibility of H2O molecules to the reaction site of the succinimide intermediate.