bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surface‐modified silica nanoparticles for reinforcement of PMMA
Authors: Hong R. Y. , Fu H. P. , Zhang Y. J. , Liu L. , Wang J. , Li H. Z. , Zheng Y. 
Published: April 2007

AbstractPolymethyl methacrylate (PMMA) was introduced onto the surface of silica nanoparticles by particle pretreatment using silane coupling agent (γ‐methacryloxypropyl trimethoxy silane, KH570) followed by solution polymerization. The modified silica nanoparticles were characterized by Fourier‐transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and thermogravimetric analysis (TGA). Sedimentation tests and lipophilic degree (LD) measurements were also performed to observe the compatibility between the modified silica nanoparticles and organic solvents. Thereafter, the PMMA slices reinforced by silica‐nanoparticle were prepared by in situ bulk polymerization using modified silica nanoparticles accompanied with an initiator. The resultant polymers were characterized by UV–vis, Sclerometer, differential scanning calorimetry (DSC). The mechanical properties of the hybrid materials were measured. The results showed that the glass transition temperature, surface hardness, flexural strength as well as impact strength of the silica‐nanoparticle reinforced PMMA slices were improved. Moreover, the tensile properties of PMMA films doped with silica nanoparticles via solution blending were enhanced. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Poly(acrylamide‐allyl glycidyl ether) cryogel as a novel stationary phase in dye‐affinity chromatography
Authors: Demiryas Nazan , Tüzmen Nalan , Galaev Igor Yu , Pişkin Erhan , Denizli Adil 
Published: April 2007

AbstractPoly(acrylamide‐allyl glycidyl ether) [poly(AAm‐AGE)] cryogel was prepared by bulk polymerization which proceeds in an aqueous solution of monomers frozen inside a glass column (cryo‐polymerization). After thawing, the monolithic cryogel contains a continuous polymeric matrix having interconnected pores of 10–100 μm size. Cibacron Blue F3GA was immobilized by covalent binding onto poly(AAm‐AGE) cryogel via epoxy groups. Poly(AAm‐AGE) cryogel was characterized by swelling studies, FTIR, scanning electron microscopy, and elemental analysis. The equilibrium swelling degree of the poly(AAm‐AGE) monolithic cryogel was 6.84 g H2O/g cryogel. Poly(AAm‐AGE) cryogel containing 68.9 μmol Cibacron Blue F3GA/g was used in the adsorption/desorption of human serum albumin (HSA) from aqueous solutions and human plasma. The nonspecific adsorption of HSA was very low (0.2 mg/g). The maximum amount of HSA adsorption from aqueous solution in acetate buffer was 27 mg/g at pH 5.0. Higher HSA adsorption value was obtained from human plasma (up to 74.2 mg/g). Desorption of HSA with a purity of 92% from Cibacron Blue F3GA attached poly(AAm‐AGE) cryogel was achieved using 0.1M Tris/HCl buffer containing 0.5M NaCl. It was observed that HSA could be repeatedly adsorbed and desorbed with poly(AAm‐AGE) cryogel without significant loss in the adsorption capacity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Carboxyl‐terminated butadiene acrylonitrile rubber/epoxy polymer alloys as damping adhesives and energy absorbable resins
Authors: Kishi Hajime , Nagao Atsushi , Kobayashi Yusaku , Matsuda Satoshi , Asami Toshihiko , Murakami Atsushi 
Published: April 2007

AbstractCarboxyl‐terminated butadiene acrylonitrile (CTBN) liquid rubber/epoxy (diglycidyl ether of bisphenol‐A: DGEBA) / diamino diphenyl methane (DDM) resins, in which CTBN was 60 wt % as the major component, were formulated to evaluate the damping and adhesive properties. In cases where acrylonitrile (AN) was 10∼18 mol % as copolymerization ratio in CTBN, the blend resins showed micro‐phase separated morphologies with rubber‐rich continuous phases and epoxy‐rich dispersed phases. The composite loss factors (η) for steel laminates, which consisted of two steel plates with a resin layer in between, depended highly on the environmental temperature and the resonant frequencies. On the other hand, in the case where AN was 26 mol % in CTBN, the cured resin did not show clear micro‐phase separation, which means the components achieve good compatibility in nano‐scale. This polymer alloy had a broad glass‐transition temperature range, which resulted in the high loss factor (η > 0.1) for the steel laminates and excellent energy absorbability as the bulk resin in a broad temperature range. Also the resin indicated high adhesive strengths to aluminum substrates under both shear and peel stress modes. The high adhesive strengths of the CTBN/epoxy polymer alloy originated in the high strength and the high strain energy to failure of the bulk resin. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Determination of some physical and mechanical properties of laminated veneer lumber impregnated with boron compounds
Authors: Özçifçi Ayhan , örs Yalçın , Uysal Burhanettin 
Published: April 2007

AbstractThe aim of this study was to determine the effects of Tanalith‐C 3310 (T‐C 3310), borax (Bo), boric acid (Ba), borax + boric acid (Bo + Ba), and diammonium phosphate (D) impregnations for some physical and mechanical properties of laminated veneer lumber (LVL). The veneers used for the LVL samples (based on BS EN 204) were cut from Scots pine (Pinus sylvestris L.), oriental beech (Fagus orientalis L.), and poplar (Populus nigra). They were impregnated with full‐cell method according to ASTM‐D 1413 standards and bonded with phenol formaldehyde (PF) and melamine formaldehyde (MF) adhesives. The following parameters have been tested: density, compression strength, bending strength, modulus of elasticity (MOE) in bending, and shear strength tests. Test results obtained from this study showed that impregnation with Boric acid and Tanalith‐C 3310 (based acidic characteristic) affected the strength of LVL negatively, when the wood material is impregnated with acidic impregnations and bonded with PF, which is an alkali, the glue‐line becomes more elastic, the bonding strength of adhesive weakens. Boric acid and Tanalith‐C 3310 impregnations could not be recommended for LVL elements exposed to bending or shear strength. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Electrodeposition of NiOx/PANI composite film and its catalytic properties towards electrooxidations of polyhydroxyl compounds
Authors: Peng Xu‐Yuan , Li Wei , Liu Xiao‐Xia , Hua Pei‐Jie 
Published: April 2007

AbstractElectrocodeposition of nickel oxide (NiOx) and polyaniline (PANI) was conducted through cyclic voltammetric scans in an aqueous solution of NiSO4 and aniline. Characterizations of the obtained NiOx/PANI composite film by XRD and FTIR indicated that the film composed of NiOx and PANI, in which nickel oxide was in the form of Ni2O2(OH). Ni(II)/Ni(III) redox couple appeared at 0.30 V versus SCE on the cyclic voltammogram (CV) of the composite film. Electrooxidations of glucose and fructose occurred at the potential where nickel oxide existed in higher oxidation state. The anodic current densities at 0.46 V for the electrooxidations were linearly dependent on the concentration of polyhydroxyl compounds from 1 to 100 mM for glucose and 10 to 100 mM for fructose, respectively. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
New solvent for polyrotaxane. III. Dissolution of a poly(ethylene glycol)/cyclodextrin polyrotaxane in a calcium thiocyanate aqueous solution or N‐methylmorpholine‐N‐oxide monohydrate
Authors: Araki Jun , Kataoka Toshiyuki , Ito Kohzo 
Published: April 2007

AbstractCalcium thiocyanate [Ca(SCN)2] aqueous solutions above 40 wt % and N‐methylmorpholine N‐oxide (NMMO) monohydrate, which are known to dissolve cellulose, were found to be good solvents for a polyrotaxane comprising α‐cyclodextrin and poly(ethylene glycol). The polyrotaxane could be dissolved up to 12 and 10 wt % in a 40 wt % Ca(SCN)2 aqueous solution and NMMO, respectively. These are the first instances of a neutral aqueous solution and a cyclic amine oxide, respectively, that readily dissolve the polyrotaxane. These new good solvents, as well as other solvents of the polyrotaxane, except for dimethyl sulfoxide, are identical to those of cellulose, indicating that the dissolution mechanism of the polyrotaxane is dominated by intra‐ and intermolecular hydrogen bonding of the molecule similar to that of cellulose dissolution. The concentrated polyrotaxane solution in a 40 wt % Ca(SCN)2 aqueous solution showed apparent thixotropy and spontaneous gelation of the solution caused by a gradual increase in its viscosity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Triblock poly(lactic acid)‐b‐poly(ethylene glycol)‐b‐poly(lactic acid)/paclitaxel conjugates: Synthesis, micellization, and cytotoxicity
Authors: Xie Zhigang , Lu Tiancheng , Chen Xuesi , Lu Changhai , Zheng Yonghui , Jing Xiabin 
Published: April 2007

AbstractA triblock poly(lactic acid)‐b‐poly(ethylene glycol)‐b‐poly(lactic acid) (PLA–PEG–PLA)/paclitaxel (PTX) conjugate was synthesized by the reaction of carboxyl‐terminated copolymer PLA–PEG–PLA with PTX in the presence of dicyclohexylcarbodiimide and dimethylaminopyridine. Carboxyl‐terminated copolymer PLA–PEG–PLA was prepared by the reaction of the hydroxyl end groups in copolymer PLA–PEG–PLA with succinic anhydride. Its structure was confirmed by NMR and gel permeation chromatography. The PLA–PEG–PLA/PTX conjugates could self‐assemble into micelles in aqueous solutions with a low critical micelle concentration. Dynamic light scattering and environmental scanning electron microscopy analyses of the PLA–PEG–PLA/PTX micelles revealed their spherical structure and size of 220 nm. The antitumor activity of the conjugate against woman Hela cancer cells, evaluated by the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide method, showed that the conjugates had an antitumor activity similar to that of pure PTX. The obtained PLA–PEG–PLA/PTX conjugates are expected to be used in clinical practice. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Effect of minor addition of xanthan on cross‐linking of rice starches by dry heating with phosphate salts
Authors: Chung Hyun‐Jung , Min Deulre , Kim Jong‐Yea , Lim Seung‐Taik 
Published: April 2007

AbstractEffects of xanthan on the crosslinking of normal and waxy rice starches using a mixture of phosphate salts (sodium trimetaphosphate and sodium tripolyphosphate, 99 : 1, dry solid basis) were investigated. The starch (158.4 g, dry solids) was dispersed in an aqueous solution containing xanthan and phosphate salts (1.6 and 0.6 g in 280 mL water, respectively), and the slurry was dried overnight at 45°C until the moisture content was less than 10%. The dry cake was then ground into powders and heated for 2 h at 130°C in a convection oven. The pasting viscosity, paste clarity, melting and in vitro digestion behaviors of the starches with modifying agents (xanthan and phosphate salts) were investigated. The heat treated starches displayed enhanced shear stability and reduced breakdown, as evidences of crosslinking. Xanthan (1.0% based on starch solids) enhanced the crosslinking effects in the viscosity profile. Waxy rice starch evidenced more profound viscosity changes than did normal rice starch, indicating it was more susceptible to the heat treatment. The waxy rice starch heated with the mixture of phosphate salts and xanthan exhibited a continuous increase in pasting viscosity without any breakdown. Under a DSC analysis, melting enthalpy decreased but melting temperature increased somewhat as results of the heat treatment with xanthan. In an in vitro digestion analysis, the starches treated with xanthan exhibited decreases in the maximum digestion level, and increases in the resistant starch (RS) content. Dry heating, however, increased the digestion rate and glycemic index (GI) regardless of the presence of phosphate salts or xanthan indicating that the starches were thermally degraded. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Characterization of phase morphology of polymer melts (PP/PE blends) via rheology
Authors: Vincze‐Minya Krisztina A. , Schausberger Alois 
Published: April 2007

AbstractThe viscoelastic behavior of high impact polypropylene (PP) melts, a multiphase system with an isotactic PP matrix and inclusions consisting of mainly amorphous ethylene–propylene copolymer (EP), is strongly influenced by the size of small inclusions. The dynamic moduli of such two‐phase systems (reactor products) are well described by Palierne's emulsion model. For this analysis the reactor product is separated into matrix and dispersed phase via the different solubility in xylene. This analysis also provides information on the ratio interfacial tension to particle size of the dispersed phase. With morphology data (particle size) of the solidified heterophasic samples (Transmission Electron Microscopy), we estimate the interfacial tension between PP and EP copolymer via the emulsion model of Palierne and from the relaxation time spectra according to Gramespacher and Meissner. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Effect of natural rubber on wood‐reinforced tannin composites
Authors: Mosiewicki M. A. , Aranguren M. I. , Curvelo A. A. S. , Borrajo J. 
Published: April 2007

AbstractNatural rubber latex was added to composite materials formulated from a quebracho tannin adhesive crosslinked with hexamethylenetetramine and wood flour as a reinforcing filler. The final microstructure of the thermoset modified by the addition of different concentrations of latex was observed by scanning electron microscopy. The flexural and impact behavior of the modified materials was analyzed and related to the final microstructure of the composites. The effect of exposing the materials to humid environments was also evaluated. The measurements indicated that the addition of latex did not significantly reduce water absorption. However, it facilitated the preparation process of samples with low filler contents because of the increased viscosity of the mixture, which inhibited particle settling. On the other hand, the flexural properties increased with the addition of latex‐containing proteins through a reaction similar to tanning in leathers. The impact properties presented a similar trend, with the largest change occurring between 0 and 5% natural rubber in the matrix formulation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Synthesis and characterization of polyamide powders for sorption of reactive dyes from aqueous solutions
Authors: Suteu Daniela , Bilba Doina , Dan Florin 
Published: April 2007

AbstractPolyamide (PA) fine powders or granules, obtained by anionic solution/suspension polymerization of lactams, were used for the sorption of reactive dye Brilliant Red HE‐3B from aqueous solutions. They provided a relatively large surface area and porosity that allowed an increased sorption rate. The visible molecular absorption spectroscopy was used to evaluate the performance of the investigated systems. Under the same conditions, the sorption capacity of polyamide particles decreases in the following manner: PA6‐powders > PA12‐powders > PA4‐granules. The effect of pH, initial dye concentration, temperature, and sorption duration on dye removal was studied for the PA6‐powder/reactive dye system. The equilibrium sorption isotherms have been analyzed by the linear, Freundlich, and Langmuir models. The data conform to a Langmuir isotherm and a pseudosecond order kinetic model, respectively. In addition, the apparent thermodynamic parameters were calculated and the obtained values support the conclusion that the reactive dye molecules are adsorbed onto PA‐powders by an entropy‐driven, endothermic process. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Characterization of acrylic acid‐grafted PP membranes prepared by plasma‐induced graft polymerization
Authors: Choi Eun‐Young , Moon Seung‐Hyeon 
Published: April 2007

AbstractAcrylic acid (AA)‐g‐polypropylene (PP) membranes were prepared by grafting AA on to a microporous PP membrane via plasma‐induced graft polymerization. The grafting of AA to the PP membrane was investigated using Fourier transform infrared spectroscopy (FTIR). Pore‐filling of the membranes was confirmed by field emission‐scanning electron microscopy (FESEM) and energy dispersing X‐ray (EDX). Ion exchange capacity (IEC), membrane electric resistance, transport number and water content were measured and analyzed as a function of grafting reaction time. The prepared AA‐g‐PP membranes showed moderate electrochemical properties as a cation‐exchange membrane. In particular, membranes with a degree of grafting of 155% showed good electrical properties, with an IEC of 2.77 mmol/g dry membrane, an electric resistance of 0.4 Ω cm2 and a transport number of 0.96. Chronopotentiometric measurements indicated that AA‐g‐PP membranes, with a high IEC had a sufficient conducting region in the membrane. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Impact of impregnation with boron compounds on the surface hardness of varnished wood
Authors: Ors Yalçın , Atar Musa , Çolakoğlu Mustafa H. 
Published: April 2007

AbstractThis study was performed to determine the impact of impregnation with boron compounds on the surface hardness of varnished wood materials. For this purpose, test specimens prepared from Oriental beech (Fagus orientalis Lipsky) and oak (Quercus petreae Lipsky), which met the requirements of ASTM D 358, were impregnated according to ASTM D 1413 with boric acid and borax by a vacuum technique. After impregnation, the surfaces were coated by cellulosic, synthetic, polyurethane, waterborne, acrylic, and acid hardening varnishes in accordance with ASTM D 3023. The surface hardness of the specimens after the varnishing process was determined in accordance with ASTM D 4366. According to the wood type, impregnation material, and varnish type, the surface hardness was highest for the oak impregnated with borax and acrylic varnish and lowest for the oak impregnated with borax and synthetic varnish. Therefore, impregnation with boron compounds showed an increasing impact on the surface hardness of the varnished wood. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Amidine Analogues of Melphalan: Synthesis, Cytotoxic Activity, and DNA Binding Properties
Authors: Bielawska Anna , Bielawski Krzysztof , Anchim Tomasz 
Published: April 2007

AbstractDesign, synthesis, and cytotoxic activity of amidine derivatives of melphalan are described and structure‐activity relationships are discussed. Evaluation of the cytotoxicity of these compounds employing a MTT assay and inhibition of [3H]thymidine incorporation into DNA in both MDA‐MB‐231 and MCF‐7 human breast cancer cells demonstrated that these compounds were more active than melphalan. Data from the ethidium displacement assay showed that these compounds were able to bind in the minor groove‐binding mode in AT sequences of DNA. The cytotoxic properties of the amidine analogues of melphalan towards cultured human breast cancer cells correlate with topoisomerase II inhibitory properties but not with DNA‐binding properties.
Synthesis of Pyrazolo[4′,3′:5,6]pyrano[2,3‐d]pyrimidine Derivatives for Antiviral Evaluation
Authors: Shamroukh Ahmed H. , Zaki Magdi E. A. , Morsy Eman M. H. , Abdel‐Motti Faiza M. , Abdel‐Megeid Farouk M. E. 
Published: April 2007

Abstract6‐Amino‐3‐methyl‐4‐(4‐nitrophenyl)‐2,4‐dihydropyrano[2,3‐c]pyrazole‐5‐carbonitrile (1) was used as a precursor for preparation of some novel 3,7‐dimethyl‐4‐(4‐nitrophenyl)‐2,4‐dihydropyrazolo[4′,3′:5,6]pyrano[2,3‐d]pyrimidine derivatives 3–6, and some of their corresponding N2‐ and C5‐S‐acyclic nucleosides 7 and 8. Furthermore, the preparation of 5‐amino‐1‐[3,7‐dimethyl‐4‐(4‐nitrophenyl)‐2,4‐dihydropyrazolo[4′,3′:5,6]pyrano[2,3‐d]pyrimidin‐5‐yl]‐1H‐pyrazole derivatives 10–16 were described. Some of the prepared products were selected and tested for antiviral activity against Herpes Simplex Virus type‐1 (HSV‐1).
Triazole: the Keystone in Glycosylated Molecular Architectures Constructed by a Click Reaction
Authors: Dondoni Alessandro 
Published: April 2007

AbstractThe copper(I)‐catalyzed modern version of the Huisgen‐type azide–alkyne cycloaddition to give a 1,4‐disubstituted 1,2,3‐triazole unit is introduced as a powerful ligation method for glycoconjugation. Owing to its high chemoselectivity and tolerance of a variety of reaction conditions, this highly atom‐economic and efficient coupling reaction is especially useful for the effective construction of complex glycosylated structures such as clusters, dendrimers, polymers, peptides, and macrocycles. In all cases the triazole ring plays a key role by locking into position the various parts of these molecular architectures. The examples reported and briefly discussed in this short review highlight the use of this reaction in carbohydrate chemistry and pave the way to further developments and applications.
A Comparison of Parametric and Nonparametric Methods for Normalising cDNA Microarray Data
Authors: Khondoker Mizanur R. , Glasbey Chris A. , Worton Bruce J. 
Published: April 2007

AbstractNormalisation is an essential first step in the analysis of most cDNA microarray data, to correct for effects arising from imperfections in the technology. Loess smoothing is commonly used to correct for trends in log‐ratio data. However, parametric models, such as the additive plus multiplicative variance model, have been preferred for scale normalisation, though the variance structure of microarray data may be of a more complex nature than can be accommodated by a parametric model. We propose a new nonparametric approach that incorporates location and scale normalisation simultaneously using a Generalised Additive Model for Location, Scale and Shape (GAMLSS, Rigby and Stasinopoulos, 2005, Applied Statistics, 54, 507–554). We compare its performance in inferring differential expression with Huber et al.'s (2002, Bioinformatics, 18, 96–104) arsinh variance stabilising transformation (AVST) using real and simulated data. We show GAMLSS to be as powerful as AVST when the parametric model is correct, and more powerful when the model is wrong. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Evidence for a Role of the Membrane‐Proximal Region of Herpes Simplex Virus Type 1 Glycoprotein H in Membrane Fusion and Virus Inhibition
Authors: Galdiero Stefania , Falanga Annarita , Vitiello Mariateresa , D'Isanto Marina , Collins Craig , Orrei Veronica , Browne Helena , Pedone Carlo , Galdiero Massimiliano 
Published: April 2007

AbstractWe have identified a putative membrane‐interacting domain preceding the transmembrane domain of the Herpes simplex virus type 1 (HSV‐1) glycoprotein H (gH). Peptides derived from this region interact strongly with membranes and show a high tendency to partition at the interface. This region is predicted to bind at the membrane interface by adopting an α helical structure. Peptides representing either the HSV‐1 gH pretransmembrane region or a scrambled control with a different hydrophobic profile at the point of interface have been studied. The peptides derived from this domain of gH induce the fusion of liposomal membranes, adopt helical conformations in membrane mimetic environments and are able to inhibit HSV‐1 infectivity. The pretransmembrane region appears to be a common feature in viral fusion proteins of several virus families, and such a feature might be related to their fusogenic function. The identification of membrane‐interacting regions capable of modifying the biophysical properties of phospholipid membranes lends weight to the view that such domains might function directly in the fusion process and could facilitate the future development of HSV‐1 entry inhibitors.