bluuebunny/crossref_metadata_2025_split huggingface dataset:
Development of nanostructured polyaniline dispersed smart anticorrosive composite coatings
Authors: Alam Javed , Riaz Ufana , Ahmad Sharif 
Published: January 2008

AbstractModern engineering science and nanotechnology have hastened the development of high performance corrosion‐resistant coatings having a broad spectrum of effectivity under a wider range of hostile environments. The formulation of such coating systems is expected to cause a major revolution in the corrosion world. Conducting polymers have recently proved to be an effective alternative to phosphate–chromate pretreatment that is hazardous due to toxic hexavalent chromium. Moreover, improvements in environmental impact can be achieved by utilizing nanostructured particulates in coating and eliminating the requirement of toxic solvents. The paper reports some preliminary investigations on the corrosion resistance performance of nanostructured methyl orange (MO)‐doped polyaniline (PANI)/castor oil polyurethane (COPU) composite coatings on mild steel (MS). The nanostructure of the MO‐PANI was confirmed by transmission electron microscopy (TEM). The corrosion protective performance was evaluated by physico‐mechanical properties, corrosion rate, and open circuit potential measurements. These coatings were found to act as “corrosion sensors” by exhibiting different colors when placed in acid as well as alkaline media. The protective behavior of coatings was attributed to the formation of a passive iron oxide/dopant layer at the metal‐coating interface that impedes the penetration of the corrosive ions. Copyright © 2008 John Wiley & Sons, Ltd.
Late‐appearing Philadelphia chromosome in childhood acute myeloid leukemia
Authors: Shah Niketa , Leaker Michael T. , Teshima Ikuko , Baruchel Sylvain , Abdelhaleem Mohamed , Ye Charles C. 
Published: January 2008

AbstractA 3‐year‐old female was diagnosed with acute myeloid leukemia (AML‐M2). The disease was refractory to various chemotherapeutic agents. Cytogenetic analysis revealed a clone with trisomy 8 at diagnosis that was replaced by a clone containing a t(11;15) and del(20q) by the end of the second induction. A new clone, characterized by a Philadelphia chromosome, with the minor BCR/ABL p190 transcript, emerged 14 months after diagnosis and remained to the end of disease course. The late occurrence of the Philadelphia chromosome in AML has been documented rarely in adults. Pediatr Blood Cancer 2008;50:1052–1053. © 2008 Wiley‐Liss, Inc.
Multimodality treatment of osteosarcoma: Radiation in a high‐risk cohort
Authors: Mahajan Anita , Woo Shiao Y. , Kornguth David G. , Hughes Dennis , Huh Winston , Chang Eric L. , Herzog Cynthia E. , Pelloski Christopher E. , Anderson Pete 
Published: January 2008

AbstractPurposeChemotherapy during radiation and/or bone‐seeking radioisotope therapy (153‐samarium; 1 mCi/kg) during radiation may improve osteosarcoma cancer control.Patients and MethodsWe analyzed our preliminary radiation experience in high‐risk, metastatic, and/or recurrent patients during a consecutive period of 20 months (May 2005–December 2006).ResultsThirty‐nine high‐risk osteosarcoma patients had radiotherapy; 119 sites were irradiated. A median four sites were irradiated per patient (range 1–14). The median radiation dose and number of fractions of radiation was 30 Gy in 10 fractions (range 10–70 Gy in 4–35 fractions). Chemotherapy, most commonly ifosfamide or methotrexate, was used in 80% (100/119) radiotherapy courses. Of 38 painful sites, 29 had improvement (76%), 4 had no change (10%), and 5 had more pain (13%). Objective and potentially durable responses were documented using PET‐CT and bone scans with persistent and sustained reduction of standard uptake values (SUVs; initial SUV of indication lesion 9.5 became <4 at all subsequent time points) and serial bone scans [improvement in 29/39 (72%); stable 10/39 (25%), worse 1/39 (3%)]. The actuarial 4‐year survival from development of metastasis was 39%.ConclusionsOur early results suggest that the use of multimodality therapy including chemotherapy with radiation in unresectable osteosarcoma may be beneficial. Pediatr Blood Cancer 2008;50:976–982. © 2008 Wiley‐Liss, Inc.
Processing and performance evaluation of hollow microspheres filled epoxy composites
Authors: Saha Mrinal C. , Nilufar Sabrina , Major Mosi , Jeelani Shaik 
Published: January 2008

AbstractMicrospheres filled epoxy composites are fabricated, using two types of hollow glass microspheres, namely, Fillite‐500 and K‐15. Fillite‐500 microspheres are relatively stronger and denser (avg. crushed strength ∼17 MPa and density ∼0.45 kg/m3) than K‐15 microspheres (avg. crushed strength ∼2 MPa and density ∼0.15 kg/m3). Each type of microspheres in the range of 10–70 vol% are added into a low viscosity two‐part epoxy resin (SC‐15) system in several steps and are mixed together meticulously to avoid breakage of the microspheres during mixing. The epoxy/microspheres mixture is then cured at room temperature (about 70°F) inside an oven for 24 h followed by post curing at 200°F for 4 h. One of the objectives of this research is to determine the maximum amount of microspheres that can be mixed uniformly without aid of diluents. Microstructural examinations reveal that the microspheres are fairly distributed uniformly through out the epoxy matrix up to 70 vol% for Fillite‐500 and 60 vol% for K‐15. It is found that addition of microspheres results in the reduction of density of the neat epoxy up to 28% with Fillite‐500 and up to 54% with K‐15. Thermo mechanical analysis results show that the coefficient of thermal expansion of epoxy matrix is reduced up to 66% with Fillite‐500 and up to 51% with K‐15.Compressive behavior for the epoxy/Fillite‐500 system is found to be different than the epoxy/K‐15 system. Failure analysis results indicate that the failure processes are also different for both the systems. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
Study of nanocomposites prepared by melt blending TPU and montmorillonite
Authors: Zou Hua , Ran Qianping , Wu Shishan , Shen Jian 
Published: January 2008

AbstractThe intercalated thermoplastic polyurethane (TPU)/montmorillonite (MMT) nanocomposites were prepared by melt blending TPU and organic octadecylammonium‐treated MMT (ODA‐MMT) at 150–155°C for 10 min. Compared with those of TPU/montmorillonite composites, the interface interaction and dispersion of TPU/ODA‐MMT nanocomposites were improved remarkably. The tensile strength and tear strength of the TPU/ODA‐MMT nanocomposites were higher than those of pure TPU, and the MMT platelets dispersed on the nanometer scale in TPU matrix had reinforce effect. Due to the “labyrinth” effect of the MMT platelets dispersed on the nanometer scale in the TPU matrix caused by the eximious barrier and strong interaction between the MMT platelets and TPU, the temperature of initial weight loss of the TPU/ODA‐MMT nanocomposites was higher than that of pure TPU and TPU/MMT composites in the second thermodegradation step. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
Erosive wear of carbon fabric reinforced polyetherimide composites: Role of amount of fabric and processing technique
Authors: Bijwe J. , Rattan Rekha , Fahim M. , Tiwari Sudhir 
Published: January 2008

AbstractPlain weave carbon fabric (CF) reinforced Polyetherimide (PEI) composites, hereafter referred to as CF‐PEI composites, containing 40, 55, 65, 75, and 85 vol% of CF were developed using impregnation technique and compression moulding. An additional CF‐PEI composite containing 52 vol% of CF was also fabricated using film technique and compression moulding. These composites were developed in order to explore the effect of fabric content and processing technique on strength properties and erosive wear performance of PEI. These six composites along with unfilled PEI were evaluated for their physical and mechanical properties. The erosive wear performance of these materials was evaluated using angular silica particles as erodent at an impingement angle of 30°. It was observed that fabric content strongly influenced the strength properties as well as erosion resistance. Strength performance, however, did not linearly increase with increase in fabric content. Lowest (40%) and highest (85%) amount of fabric proved least effective in this regard. Similar observations were observed in the case of wear resistance (WR). CF in the range of 55–75 vol% proved optimum for strength properties and wear performance barring PEI, which showed highest WR. Between the two processing techniques, impregnation technique (I) proved far superior to the film technique (F) in both strength and wear performance. A fairly good correlation was observed between erosion resistance and a product of interlaminar shear strength, resilience, and elongation. SEM studies on worn surfaces supported the wear behavior. POLYM. COMPOS., 2008. © 2008 Society of Plastics Engineers
Characterization and crystallization behavior of poly(ethylene‐co‐trimethylene terephthalate) copolymers
Authors: Zou Hantao , Li Guang , Jiang Jianming , Yang Shenglin 
Published: January 2008

AbstractA series of poly(ethylene‐co‐trimethylene terephthalate) (PETT) copolymers were prepared by polycondensation. The synthesized PETT are block copolymers and the content of poly(trimethylene terephthalate) (PTT) units incorporated into the copolymers are always larger than that fed in the polymerization. The nonisothermal crystallization at the different cooling rates was studied by means of differential scanning calorimetry. The copolymers develop the crystallization later and show the lower melting temperature than the corresponding enriched homopolymers. The modified Avrami analysis fit well the nonisothermal crystallization of these polymers. The overall rate of crystallization of PTT is fastest and that of PET is slowest, whereas the copolymers are between them at the same cooling rate. The minor PET units incorporated into PTT polymer chains reduce the crystallization of PTT segments, but the present minor PTT units in the PET chains seem to accelerate the crystallization of PET segments. The Avrami exponent nvaries in the range of 3–4, indicating that the nonisothermal crystallization follows the homogeneous nucleation and two‐ to three‐dimensional growth mechanism. Wide angle X‐ray diffraction analysis explains that the PET and PTT units do not cocrystallize and it is considered as the enriched polymer segments to crystallize during crystallization. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Nonuniformity of phase structure in immiscible polymer blends
Authors: Fortelný Ivan , Lapčíková Monika , Lednický František , Starý Zdeněk , Kruliš Zdeněk 
Published: January 2008

AbstractThis article is focused on the phase structure development in immiscible polymer blends during melt mixing. Nonuniformity of the phase structure, i.e., the coexistence of areas containing particles with markedly different size distribution, was detected in quenched and compression molded samples of a number of various blends prepared by long and intensive mixing in the chamber of a Plasticorder. The same effect was found also for polystyrene/polyamide blends prepared in a twin‐screw extruder. It was shown that neglecting nonuniformity of the phase structure can lead to considerable error in evaluation of the effect of system parameters on the blend morphology. The reasons for the effect were discussed and it was found that inhomogeneous flow field in mixers is a plausible explanation of the nonuniform phase structure. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
Effects of thermal aging on isotactic polypropylene crystallinity
Authors: Law Aaron , Simon Leonardo , Lee‐Sullivan Pearl 
Published: January 2008

AbstractThe effects of elevated temperature aging on the microstructural changes of isotactic polypropylene matrix in a composite have been studied using wide‐angle X‐ray scattering (WAXS) and Fourier‐transform infrared spectroscopy (FTIR). The objective was to quantify small and slow changes in crystallinity due to thermal aging. To minimize sample variability, polypropylene resin was extracted from the molded composite plaque. Changes in crystallinity level and crystalline form were detected using WAXS after prolonged aging at 90 and 140°C. FTIR was utilized to monitor in‐situ crystallinity changes and to detect oxidation products due to thermal decomposition. The level of crystallinity was monitored by changes in the absorbance ratio of A997/A973 and A841/A973; the former ratio was found to be more sensitive for detecting crystallinity changes. Aging at 140°C resulted in oxidation. The kinetics of secondary crystallization for the aging conditions studied was characterized using Avrami plots. POLYM. ENG. SCI., 2008. © 2008 Society of Plastics Engineers
GaAs converters for high power densities of laser illumination
Authors: Oliva E. , Dimroth F. , Bett A. W. 
Published: January 2008

AbstractPhotovoltaic power converters can be used to generate electricity directly from laser light. In this paper we report the development of GaAs PV power converters with improved conversion efficiency at high power densities. The incorporation of a lateral conduction layer (LCL) on top of the window layer resulted in a considerable gain in efficiency at high illumination levels. Additional performance improvements were obtained by using a metal electrode grid design and antireflection coating optimised for monochromatic and inhomogeneous laser light. Maximum monochromatic (810 nm) optical‐to‐electrical conversion efficiency of 54·9% at 36·5 W/cm2has been achieved. The characteristics of laser power converters with p/n and n/p polarity are discussed in this paper. Moreover, different materials and doping levels were applied in the LCL. The performance of these different device structures at high laser intensity is presented and discussed. It is shown that the lateral series resistance of the cell has a major impact on the overall device performance. Copyright © 2008 John Wiley & Sons, Ltd.
Optical performance analysis of V‐trough PV concentrators
Authors: Martín N. , Ruiz J. M. 
Published: January 2008

AbstractThis paper proposes a method for the analysis of the optical losses that take place inside PV concentrators, which is useful in the design of such systems. The study is focused in V‐trough concentrators with two‐axis tracking. Those are low concentration systems that use nearly conventional flat PV modules. Optical losses are shown to depend on the cavity angle, the mirrors spectral and angular reflectance and the surfaces dirtiness. Final effective concentration ratio and relative cost should consider all these analysed factors. This will help in the search of the most efficient solution in each case. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis of poly(isobornyl acrylate) containing copolymers by atom transfer radical polymerization
Authors: Dervaux Bart , Van Camp Wim , Van Renterghem Lieven , Du Prez Filip E. 
Published: January 2008

AbstractFor the first time, a detailed study of the atom transfer radical polymerization of isobornyl acrylate (iBA) is reported. On the basis of these results, well‐defined PiBA‐containing block copolymers were synthesized, focussing on the preparation of amphiphilic poly(acrylic acid) (PAA) containing block copolymers. The precursor monomers 1‐ethoxyethyl acrylate (EEA) as well as tert‐butyl acrylate have been used to synthesize the PAA‐segments of the PiBA‐b‐PAA block copolymers. Finally, the synthesis of “block‐like” copolymers of PiBA and PEEA via a one‐pot procedure was investigated. By optimizing the copper and ligand concentration, and choosing the appropriate solvent, a controlled polymerization behaviour was obtained in all cases, as evidenced by a detailed kinetic analysis, GPC, NMR, and MALDI‐TOF data. Thermogravimetric analysis confirmed the quantitative transformation of the precursor polymer PEEA to the corresponding PAA‐containing copolymers. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1649–1661, 2008
DC Corona Electric Discharges for Air Pollution Control, 2—Ionic Intermediates and Mechanisms of Hydrocarbon Processing
Authors: Marotta Ester , Callea Alessandro , Ren Xianwen , Rea Massimo , Paradisi Cristina 
Published: January 2008

AbstractA mechanistic study is reported on i‐octane and hexane processing with +DC and −DC corona in air at room temperature and pressure. Current/voltage profiles are matched with the ion analysis data obtained by APCI mass spectrometry. With a −DC corona, the hydrocarbons do not modify the negative ion population with respect to uncontaminated air. In contrast, with a +DC corona many hydrocarbon‐derived positive ions form. O(3P) and •OH were also investigated using chemical probes (ozone formation and CO oxidation, respectively). The results, combined with efficiency and product data, suggest that with −DC corona radical initiation steps occur, whereas with +DC corona ionic reactions prevail.magnified image
Promoter methylation correlates with reduced Smad4 expression in advanced prostate cancer
Authors: Aitchison Alan A. , Veerakumarasivam Abhi , Vias Maria , Kumar Rajeev , Hamdy Freddie C. , Neal David E. , Mills Ian G. 
Published: January 2008

AbstractBACKGROUNDTransforming growth factor‐β (TGF‐β) is a potent growth inhibitor in a wide range of cell types. A transducer of TGF‐β signaling known as Mothers against decapentaplegic homologue 4 (Smad4) is a known tumor suppressor found on chromosome 18q21.1 and is typically inactivated by deletion or mutation in pancreatic and colorectal cancers. The purpose of the article is to investigate Smad4 expression, gene copy number and methylation status in advanced cases of prostate cancer.METHODSWe have employed Methylation Specific PCR (MSP) to identify methylation sites within the Smad4 promoter and combined this with quantitative real‐time PCR to look for correlates between methylation status and Smad4 expression and to examine androgen receptor (AR) expression. Bacterial artificial chromosome–comparative genomic hybridization (BAC–CGH) has been used to look for genomic amplifications and deletions which may also contribute to expression changes.RESULTSWe fail to find evidence of genomic deletions or amplifications affecting the Smad4 locus on chromosome 18 but show a correlation between promoter methylation and the loss of Smad4 expression in the same material. We confirm that the AR locus on the X chromosome is amplified in 30% of the advanced clinical samples and that this correlates with increased transcript levels as previously reported by other groups.CONCLUSIONThis indicates that epigenetic changes affect the expression of the Smad4 protein in prostate cancer and points to methylation of the promoter as a novel marker of and contributor to the disease warranting further study. Prostate 68: 661–674, 2008. © 2008 Wiley‐Liss, Inc.
Total and free PSA kinetics in patients without prostate cancer undergoing radical cystoprostatectomy
Authors: Gregorakis Alkibiades K. , Stefanakis Stefanos , Malovrouvas Dimitrios , Petraki Konstantina , Gourgiotis Dimitrios , Scorilas Andreas 
Published: January 2008

AbstractBackgroundRadical cystoprostatectomy and radical prostatectomy are the two major operations where prostate is totally and radically removed. Radical cystoprostatectomy is usually performed in patients with invasive bladder cancer. The aim of the study was to examine Total PSA, Free PSA, and Free/Total Ratio elimination kinetics after radical cystoprostatectomy.MethodsSerum PSA, Free PSA, and Free/Total Ratio were determined preoperatively, at the time of cystoprostatectomy specimen removal and then at 3, 6, 12, 24, 48, 72, and 168 hr, from seven patients with muscle invasive bladder cancer, who underwent radical cystoprostatectomy. Free and Total PSA concentrations were measured with non‐competitive immunological procedures. The elimination rates and half‐lives of Total, Free PSA and Free/Total Ratio were studied using a nonlinear regression analysis.ResultsSurgical manipulations caused about 1.5‐fold increase of PSA, 5‐fold increase in Free PSA and 3‐fold increase in Free/Total Ratio. PSA and Free PSA followed a biphasic elimination pattern of a rapid exponential (a) phase with a half‐life of 4.27 and 2.14 hr and a terminal, nonexponential (b) phase with a half‐life of 63 and 173.2 hr, respectively. Free/Total PSA Ratio followed, also, a biphasic kinetic pattern of a rapid exponential decline with a half‐life of 3.34 and a terminal non‐exponential increase with a doubling time of 43 hr.ConclusionsComparing PSA kinetics after radical cystoprostatectomy with those of radical prostatectomy, it appears that PSA follows the same elimination pattern in both models. In contrast, Free PSA and Free/Total Ratio elimination kinetics' patterns differ between the two surgical models. Prostate 68: 759–765, 2008. © 2008 Wiley‐Liss, Inc.
Volatilisation and competing processes computed for a pesticide applied to plants in a wind tunnel system
Authors: Leistra Minze , Wolters André , van den Berg Frederik 
Published: January 2008

AbstractBACKGROUND: Volatilisation of pesticides from crop canopies can be an important emission pathway. In addition to pesticide properties, competing processes in the canopy and environmental conditions play a part. A computation model is being developed to simulate the processes, but only some of the input data can be obtained directly from the literature.RESULTS: Three well‐defined experiments on the volatilisation of radiolabelled parathion‐methyl (as example compound) from plants in a wind tunnel system were simulated with the computation model. Missing parameter values were estimated by calibration against the experimental results. The resulting thickness of the air boundary layer, rate of plant penetation and rate of phototransformation were compared with a diversity of literature data. The sequence of importance of the canopy processes was: volatilisation > plant penetration > phototransformation.CONCLUSION: Computer simulation of wind tunnel experiments, with radiolabelled pesticide sprayed on plants, yields values for the rate coefficients of processes at the plant surface. As some input data for simulations are not required in the framework of registration procedures, attempts to estimate missing parameter values on the basis of divergent experimental results have to be continued. Copyright © 2008 Society of Chemical Industry
A theoretical investigation on the cycloaddition reaction between azocarbenium ions and nitriles
Authors: Li Zhi‐Ming , Wang Quan‐Rui 
Published: January 2008

AbstractThe 1,3‐dipolar cycloaddition reactions of the cationic 1,3‐dipolarophiles of azocarbenium ion 1 with HCN in the gas phase were examined using the density functional theory, QCISD method (Quadratic configuration interaction using single and double substitutions) and CCSD(T) (Coupled cluster calculations with single and double excitations and a perturbative estimate of triple contributions calculations) calculations. The theoretical results revealed that the reaction takes place via an initial formation of a 1:1 complex of the two reactants, mainly driven by charge interaction, followed by an asynchronous concerted cyclization forming the 3H‐[1,2,4]‐triazolium ion 3, which undergo [1,2]‐H shift to provide the 1H‐[1,2,4]‐triazolium ion 4. The effect of the solvent has been modeled by using the isodensity‐surface polarizable continuum (IPCM) model and the calculation showed that the reaction in CH2Cl2 solution proceeds in a similar manner as in gas phase with only a slight derivation of activation barrier. The substituent effects have also been investigated. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008