bluuebunny/crossref_metadata_2025_split huggingface dataset:
Crystallization studies on linear aliphatic n‐polyurethanes
Authors: Fernández C. E. , Bermudez M. , Versteegen R. M. , Meijer E. W. , Muller A. J. , Muñoz‐Guerra S. 
Published: June 2009

AbstractA detailed crystallization study of the linear n‐polyurethane (n‐PUR) family for n ranging from 5 to 12 was carried out by DSC supported by polarizing optical microscopy. The study embraces crystallization of all the n‐PUR under both nonisothermal and isothermal conditions. The odd and even series of n‐PUR defined by the parity of the number of methylenes (n) contained in the polymer repeating unit are considered and separately analyzed. All the members of the two series showed a thermal behavior consistent with their chemical constitution. Isothermal crystallization data were analyzed by the kinetics Avrami approach which revealed that the “crystallizability” of n‐PUR increases steadily with the flexibility of the polyurethane chain. Melting and enthalpy temperatures of isothermally and nonisothermally crystallized n‐PUR were found to vary with n according to a zig‐zag plot characteristic of odd–even effect. Given the structural similitude of n‐PUR with (n + 2)‐nylons, results were referenced to those reported for this family of polyamides. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1368–1380, 2009
Key counter ion parameters governing polluted nafion membrane properties
Authors: Bas Corine , Reymond Laetitia , Danérol Anne‐sophie , Albérola Nicole D. , Rossinot Elisabeth , Flandin Lionel 
Published: June 2009

AbstractSome properties of perfluorosulphonated ionomer membranes contaminated by a series of 10 counter ions were investigated by infrared spectroscopy (FTIR), thermogravimetric analysis coupled to mass spectroscopy (TG‐MS), and dynamic mechanical spectrometry (DMA). Distinctive parameters were extracted and regarded as a function of the cations' properties. An optimum interaction between sulfonate group and cation was found for cations with Lewis Acid Strength (LAS) in the 0.2–0.3 range. This critical value is found to be the Lewis Basic Strength (LBS‐) of the sulfonate anion in Nafion membrane. Thermal stability analyses also point out the influence of this cation parameter on the polymer degradation process. Cations with LAS values lower than LBS‐ improve the thermal stability of the side chains while cations with LAS values higher than LBS‐ enhance the thermal degradation. Moreover, the temperature of the modulus drop increases with the LAS of the counter ion. For cations with values lower 0.5, the transition is attributed to the glass relaxation of the polymer while for cations showing LAS values higher than 0.5, the loss of stiffness originates from the polymer thermal degradation process. The overview of the experimental data allows the definition of calibration curves as a function of the cations' LAS. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1381–1392, 2009
Studies on fracture behaviors of immiscible polypropylene/ethylene‐co‐vinyl acetate blends with multiwalled carbon nanotubes
Authors: Liu Li , Wang Yong , Li Yanli , Wu Jun , Xiang Fangming , Zhou Zuowan 
Published: June 2009

AbstractImmiscible polypropylene/ethylene‐co‐vinyl acetate (PP/EVA) blends with two different compositions, one (PP/EVA = 80/20) exhibits the typical sea‐island morphology and the other (PP/EVA = 60/40) exhibits the cocontinuous morphology, were prepared with different contents of f‐MWCNTs. The fracture behaviors, including notched Izod impact fracture and single‐edge notched tensile (SENT) fracture, were comparatively studied to establish the role of f‐MWCNTs in influencing the fracture toughness of PP/EVA blends. Our results showed that, for PP/EVA (80/20) system, f‐MWCNTs do not induce the fracture behavior change apparently. However, for PP/EVA (60/40) system, the fracture toughness of the blend increases dramatically with the increasing of f‐MWCNTs content. More severe plastic deformation accompanied by the fibrillar structure formation was observed during the SENT test. Furthermore, SENT test shows that the significant improvement in fracture toughness of PP/EVA (60/40) with f‐MWCNTs is contributed to the simultaneous enhancement of crack initiation energy and crack propagation energy, but largely dominated by crack propagation stage. Further results based on crystalline structures and morphologies of the blends showed that a so‐called dual‐network structure of EVA and f‐MWCNTs forms in cocontinuous PP/EVA blends, which is thought to be the main reason for the largely improved fracture toughness of the sample. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1331–1344, 2009
Chiroptical aggregates from block copolymer bearing amino acid moieties in aqueous solution
Authors: Zhao Fabao , Liu Zhilei , Feng Liang , Sun Jianping , Hu Jiwen 
Published: June 2009

AbstractOptically active poly(ethylene glycol) monomethyl ether‐b‐poly(methacryloyl‐L‐leucine methyl ester) (denoted as MPEG‐b‐PMALM) copolymers were prepared via atom transfer radical polymerization (ATRP), using bromine (Br) end‐capped poly(ethylene glycol) monomethyl ether (denoted as MPEG‐Br) as macroinitiator in the presence of CuBr/tris(2‐dimethylaminoethy1)amine (Me6TREN) as catalytic system. Broad range of morphologies, such as spherical, cylindrical, and vesicular micelles, which were prepared by initially dissolving prepared polymer in organic solvent at different concentration followed by addition various amount of water before dialysis against water to remove any added solvent, was observed by transmission electron microscope (TEM). More detailed chiroptical properties of the micelles/aggregates in aqueous solution were evaluated by circular dichroism (CD) spectroscopy as a function of micelles morphologies, polymer concentration, solvents employed, temperature, etc. The micellar solutions exhibit almost the same CD spectra regardless of its morphologies. The intensity of the CD spectra of the cylindrical micelles decreased in the molar ellipticities as the micellar concentration in water was increased. The Cotton effect was markedly changed when the solvent hydrophobicity was changed by addition of trifluoromethyl ethanol (TFME) to water. The intensity of the CD spectra decreased not too much within the temperature range from 20 °C to 90 °C, indicating good stability of the micelles upon temperature variation. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1345–1355, 2009
Copolymerization: A new tool to selectively induce poly(butylene naphthalate) crystal form
Authors: Soccio M. , Gazzano M. , Lotti N. , Finelli L. , Munari A. 
Published: June 2009

AbstractPoly(butylene/diethylene naphthalate) copolymers (PBN‐PDEN) were synthesized in bulk according to the polycondensation procedure and examined by NMR, GPC, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and XRD. At room temperature they appeared as semicrystalline materials; the copolymerization caused a lowering in the Tg value, a decrement of Tm and of the crystallization rate. Pure α or β′ form was obtained at low and high DEN unit content, respectively; crystalline form transition never occurred in the solid state, analogously to PBN. After cooling from the melt, the pure α form was always evidenced in PBN‐PDEN10 and PBN‐PDEN20, whereas the pure β′ crystal phase develops in the copolymer containing 40 mol % DEN units, independently on the cooling rate. In the case of PBN‐PDEN30 a pure α or β′ form was obtained at low and high cooling rate, respectively. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1356–1367, 2009
Preparation and characterization of multiwalled carbon nanotube dispersions in polypropylene: Melt mixing versus solid‐state shear pulverization
Authors: Pujari Saswati , Ramanathan Thillaiyan , Kasimatis Kosmas , Masuda Jun'ichi , Andrews Rodney , Torkelson John M. , Brinson L. Catherine , Burghardt Wesley R. 
Published: June 2009

AbstractDispersions of multiwalled carbon nanotubes (MWNT) in polypropylene (PP) were prepared via conventional melt batch mixing and solid‐state shear pulverization. The properties and structure of each system were assessed via linear viscoelasticity, electrical conductivity, PP crystallization kinetics, dynamic mechanical analysis, scanning electron microscopy, and small angle X‐ray scattering. Increasing either the duration or the intensity of melt mixing leads to higher degrees of dispersion of MWNT in PP, although at the cost of substantial melt degradation of PP for long mixing times. Samples prepared by pulverization exhibit faster crystallization kinetics and higher mechanical stiffness than the melt blended samples, but in contrast show no measurable low frequency elastic plateau in melt rheology, and lower electrical conductivity than melt‐mixed samples. X‐ray scattering demonstrates that neither sample has uniform dispersion down to the single MWNT level. The results illustrate that subtle differences in the size and distribution of nanotube clusters lead to differences in the nanotube networks with strong impact on bulk properties. The results also highlight distinctions between conductive networks and load transfer networks and demonstrate that a complete and comparative picture of dispersion cannot be determined by simple indirect property measurements. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 1426–1436, 2009
Hospital admission for acute painful episode following methacholine challenge in an adolescent with sickle cell disease
Authors: Knight‐Perry Jessica E. , Field Joshua J. , DeBaun Michael R. , Stocks Janet , Kirkby Jane , Strunk Robert C. 
Published: June 2009

AbstractAsthma is associated with increases in sickle cell disease (SCD)‐related morbidity and mortality. A thorough evaluation for asthma in children with SCD is important and may involve methacholine challenge (MCh). In this report, we present a 14‐year‐old male with SCD who was admitted for an acute painful episode following MCh. Pain events after MCh have not been previously reported in children with SCD. The risk–benefit ratio should be strongly considered prior to performance of MCh in this patient population, and all possible complications, including an acute painful episode, should be openly discussed with the parents and pediatric patient. Pediatr Pulmonol. 2009; 44:728–730. © 2009 Wiley‐Liss, Inc.
Relation of bone mineral density with clinical and laboratory parameters in pre‐pubertal children with cystic fibrosis
Authors: Cobanoglu Nazan , Atasoy Halil , Ozcelik Ugur , Yalcin Ebru , Dogru Deniz , Kiper Nural , Gocmen Ayhan 
Published: June 2009

AbstractTo study bone mineral density (BMD) of pre‐pubertal cystic fibrosis (CF) children, and its relation with clinical and laboratory parameters, we enrolled 16 CF (8 girls) (4–8 years), and 16 control children (8 girls) (4–8 years). After anthropometric measurements, BMD, serum calcium, phosphorus, total alkaline phosphatase (ALP), 25‐hydroxy vitamin D (25‐OHD), parathyroid hormone, osteocalcin, tumor necrosis factor (TNF)‐α, soluble TNF‐α receptor 2 (sTNFR2), and soluble IL‐2 receptor (sIL‐2R) levels, and urinary calcium and hydroxyproline excretions were assessed. Disease severity of CF patients was determined with Shwachman–Kulczycki clinical and Brasfield radiological scoring systems.The mean Shwachman–Kulczycki and Brasfield scores of CF patients were indicating well‐controlled disease. The anthropometric measurements, mean BMD values, and serum calcium, phosphorus and parathyroid hormone levels were within normal range and similar in both groups. Serum osteocalcin levels were lower, and ALP and 25‐OHD levels were higher in CF. Although 24‐hr urinary calcium excretions was higher in CF patients, hydroxyproline excretions were similar in both groups. There was no difference between two groups for the serum levels of sIL‐2R, TNF‐α and sTNFR2. Children with low vertebral z‐scores had higher serum sIL‐2R levels in both groups, but the same relation could not be shown for TNF‐α and sTNFR2.We may speculate that younger, healthier and well‐nourished patients with CF may have normal BMD, but the bone disease develop as patients get older because of the other contributing factors. Future well‐designed longitudinal studies with large cohorts might show a relation with BMD and cytokines in CF. Pediatr Pulmonol. 2009; 44:706–712. © 2009 Wiley‐Liss, Inc.
Ammonium Dinitramide (ADN)–Prilling, Coating, and Characterization
Authors: Heintz Thomas , Pontius Heike , Aniol Jasmin , Birke Christoph , Leisinger Karlfred , Reinhard Werner 
Published: June 2009

AbstractAmmonium dinitramide (ADN) is the promising oxidizer, which is expected to be applied, e.g., in solid rocket propellants. The manufacturing of spherical ADN particles (the so‐called ADN‐Prills) with useful morphology and reproducible quality is realized by means of the emulsion crystallization process.
RFID tag readability issues with palletized loads of consumer goods
Authors: Singh J. , Olsen E. , Vorst K. , Tripp K. 
Published: June 2009

AbstractRadio Frequency Identification (RFID) is an automatic identification technology, relying on storing and remotely retrieving data using devices called RFID tags. This technology is being used in enterprise supply chain management‐related applications to improve the efficiency of inventory tracking and management. However, this technology has not been able to realize its promised potential because of several factors, such as lack of congruous worldwide standards, privacy issues and less than perfect read rates in supply chain applications. This research aimed to evaluate the readability issues commonly faced by tagged cases of palletized consumer products. The variables studied in this research were product‐package type, tag type, tag location on cases, pallet pattern and forklift speed through a RFID portal representative of a dock door in a warehouse. To determine which variables were the most significant, a binary logistic regression was run. The number of tags read was inputted for the number of events and total number of products per pallet as the number of trials. The variables product content, pallet pattern, and speed, and all interactions were then included in the model. It was observed that readability greatly varies for different product‐package systems, with paper towels producing near‐perfect reads, followed by bottled water and carbonated soda cans. The slower the forklift truck speed, the better the readability across the board, and the best pallet patterns were dependent on the product‐package type. For bottled water, the best pallet pattern was column, and for carbonated soda, the interlocking pattern. Copyright © 2009 John Wiley & Sons, Ltd.
A method to measure the total scattering cross section and effective beam gas path length in a low‐vacuum SEM
Authors: Rattenberger J. , Wagner J. , Schröttner H. , Mitsche S. , Zankel A. 
Published: June 2009

AbstractA method is presented to determine the total scattering cross section of imaging gases used in low‐vacuum scanning electron microscopy or environmental scanning electron microscopy. Experimental results are presented for water vapor, nitrogen gas and ambient air for primary beam electron energies between 5 and 30 keV. The measured results are compared and discussed with calculated values. This method allows the effective beam gas path length (BGPL) to be determined. The variations of the effective BGPL with varying chamber pressure are presented. SCANNING 31: 107–113, 2009. © 2009 Wiley Periodicals, Inc.
Toward the Identification of a “Renopoietic System”?
Authors: Romagnani Paola 
Published: June 2009

Abstract
Chronic kidney disease is a leading cause of mortality and morbidity in Western countries and is estimated to affect 11% of the adult population. The possibility of treatment of chronic kidney disease has been severely impaired by our poor knowledge of the regenerative properties of the kidney. Recent results obtained in humans, together with genetic tagging experiments performed in rodents, demonstrated that the epithelial components of the cortical nephron share a unique progenitor, which can generate podocytes as well as tubular cells. Accordingly, lineage tracing experiments demonstrated that bone marrow-derived interstitial or papillary cells are not involved in the repair of injured adult renal epithelium. In addition, assessment of the markers CD24 and CD133 in adult human kidney as well as genetic tagging in rodents allowed us to identify a hierarchical population of renal progenitors arranged in a precise sequence within Bowman's capsule. The results of all of these studies suggest that the kidney contains a “renopoietic system,” with a progenitor localized at the urinary pole of Bowman's capsule, from where it can initiate the replacement and regeneration of glomerular, as well as tubular, epithelial cells. Knowledge of renal progenitor cell biology may enable a better comprehension of the mechanisms of renal repair as well as more effective targeted therapies for acute and chronic kidney diseases.
Disclosure of potential conflicts of interest is found at the end of this article.
Pulse shaping for cognitive ultra‐wideband communications
Authors: Wu Xuan‐li , Sha Xue‐jun , Li Cheng , Zhang Nai‐tong 
Published: June 2009

AbstractCognitive ultra‐wideband (C‐UWB) systems have recently received much attention because the huge bandwidth of ultra‐wideband (UWB) systems can better exploit the advantages of cognitive radio (CR) systems. Dynamic spectrum access (DSA) is a key technique in CR systems to implement dynamic spectrum change and can be easily implemented by changing the transmitted pulse shape in a C‐UWB communication system. In this paper, we propose an orthogonal expansion based pulse shaping method to implement DSA and to compensate for antenna distortion, which uses the orthogonal Hermite functions as the orthogonal basis. In order to eliminate the direct current (DC) component existing in even orthogonal Hermite functions and to reduce the computational complexity, two modified methods and a simplification procedure are also proposed. Our results indicate that the proposed orthogonal expansion based pulse shaping methods have a much lower computational complexity than the semi‐definite programming (SDP) method, while achieving a high power efficiency. Furthermore, we demonstrate that the distortion caused by the antenna effects can also be compensated during the pulse shaping process and a better signal‐to‐noise ratio (SNR) can thus be achieved. Therefore, the proposed method is very suitable for practical application in C‐UWB communications, in which the spectrum environment changes rapidly. Copyright © 2009 John Wiley & Sons, Ltd.
Modelling and control of variable speed wind turbines for power system studies
Authors: Michalke Gabriele , Hansen Anca D. 
Published: June 2009

AbstractModern wind turbines are predominantly variable speed wind turbines with power electronic interface. Emphasis in this paper is therefore on the modelling and control issues of these wind turbine concepts and especially on their impact on the power system. The models and control are developed and implemented in the power system simulation tool DIgSILENT. Important issues like the fault ride‐through and grid support capabilities of these wind turbine concepts are addressed. The paper reveals that advanced control of variable speed wind turbines can improve power system stability. Finally, it will be shown in the paper that wind parks consisting of variable speed wind turbines can help nearby connected fixed speed wind turbines to ride‐through grid faults. Copyright © 2009 John Wiley & Sons, Ltd.
A stochastic model for the simulation of wind turbine blades in static stall
Authors: Bertagnolio Franck , Rasmussen Flemming , Sørensen Niels N. , Johansen Jeppe , Madsen Helge Aa. 
Published: June 2009

AbstractThe aim of this work is to improve aeroelastic simulation codes by accounting for the unsteady aerodynamic forces that a blade experiences in static stall. A model based on a spectral representation of the aerodynamic lift force is defined. The drag and pitching moment are derived using a conditional simulation technique for stochastic processes. The input data for the model can be collected either from measurements or from numerical results from a Computational Fluid Dynamics code for airfoil sections at constant angles of attack. An analysis of such data is provided, which helps to determine the characteristics of stall. The model is applied to wind turbine rotor cases, including the stand still condition, and results are compared to experimental data. Copyright © 2009 John Wiley & Sons, Ltd.
Coenzyme Q10 is decreased in fibroblasts of patients with methylmalonic aciduria but not in mevalonic aciduria
Authors: Haas D. , Niklowitz P. , Hörster F. , Baumgartner E. R. , Prasad C. , Rodenburg R. J. , Hoffmann G. F. , Menke T. , Okun J. G. 
Published: June 2009

SummaryThe content of coenzyme Q10 (CoQ10) was examined in skin fibroblasts of 10 patients with mevalonic aciduria (MVA) and of 22 patients with methylmalonic aciduria (MMA). Patients with these inborn errors of metabolism are thought to be at risk for CoQ10 depletion either by direct inhibition of the proximal pathway of CoQ10 synthesis (MVA) or indirectly by inhibition of mitochondrial energy metabolism (MMA). We demonstrated that CoQ10 concentrations were not significantly different from controls in MVA patients, suggesting that there may be upregulatory effects. On the other hand the CoQ10 content in fibroblasts of patients with MMA was significantly reduced.
Black hip, fracture neck of femur and scoliosis: A case of ochronosis
Authors: Zacharia B. , Chundarathil J. , Ramakrishnan V. , Krishnankutty R. M. , Veluthedath R. , Puthezhath K. , Varughese I. 
Published: June 2009

SummaryBackground: Ochronosis is a very rare disorder with an incidence of 2 to 5 per million live births. It is a genetic disorder with autosomal recessive inheritance. It is characterized by dark brown pigmentation of cartilage, capsules of joints and other soft tissues. Ochronosis usually presents as ochronotic arthropathy and spondylosis. Purpose: This article describes a very rare presentation of scoliosis and fracture of the neck of the femur in a patient with ochronosis. Methods: A 65‐year‐old woman with left‐sided scoliosis presented to us following a fall with fracture of the neck of the femur on the left side. Radiological examination and biochemical study of urine were consistent with ochronosis. Procedure and results: We have treated the patient by excision arthroplasty. Conclusion: We report a case of scoliosis, fracture of the neck of the femur and ochronosis occurring together in a patient.
Shape-Controlled Synthesis of ZnS Nanostructures: A Simple and Rapid Method for One-Dimensional Materials by Plasma
Authors: Peng Hu , Liuyang Bai , Lingjie Yu , Jinlin Li , Fangli Yuan , Yunfa Chen 
Published: June 2009

Abstract
In this paper, ZnS one-dimensional (1D) nanostructures including tetrapods, nanorods, nanobelts, and nanoslices were selectively synthesized by using RF thermal plasma in a wall-free way. The feeding rate and the cooling flow rate were the critical experimental parameters for defining the morphology of the final products. The detailed structures of synthesized ZnS nanostructures were studied through transmission electron microscope, X-ray diffraction, and high-resolution transmission electron microscope. A collision-controlled growth mechanism was proposed to explain the growth process that occurred exclusively in the gas current by a flowing way, and the whole process was completed in several seconds. In conclusion, the present synthetic route provides a facile way to synthesize ZnS and other hexagonal-structured 1D nanostructures in a rapid and scalable way.