bluuebunny/crossref_metadata_2025_split huggingface dataset:
Numerical analysis of effect of asymmetric stern of ship on its screw propeller efficiency
Authors: Abramowski Tomasz , Żelazny Katarzyna , Szelangiewicz Tadeusz 
Published: March 2011

Numerical analysis of effect of asymmetric stern of ship on its screw propeller efficiency
During designing the ship its designer tends to achieve as-high-as possible efficiency of ship's propulsion system. The greatest impact on the efficiency is introduced by ship's screw propeller whose efficiency depends not only on its geometry but also distribution of wake current velocity. To change wake current distribution and improve propeller efficiency an asymmetric form is usually applied to stern part of ship hull. This paper presents results of numerical analysis of wake current velocity distribution, performed by using a CFD method for a B 573 ship of symmetric stern and the same ship of an asymmetric stern. Next, the mean values of screw propeller efficiency in non-homogenous water velocity field were calculated for both the hull versions of B 573 ship.
Influence of main design parameters of ship propeller shaft water-lubricated bearings on their properties
Authors: Litwin Wojciech 
Published: March 2011

Influence of main design parameters of ship propeller shaft water-lubricated bearings on their properties
In recent years more and more frequently can be met ships in which propeller shaft water-lubricated polymer bearings have been applied. It results from their simplicity and associated relatively low initial and operational cost as compared with the complex classical sealed system based on oil-lubricated bearings. It is worth mentioning that the water-lubricated bearings are also environmentally friendly as no risk of pollution with lubricating oil used in classical systems, is involved. Design procedure of bearings in question based on materials made available by producers is relatively simple. However it turns out that choice of an appropriate sliding material, clearance value and optimum arrangement of lubricating grooves may greatly influence bearing's properties. As results from the performed research investigations, bearing of the kind is a highly sensitive unit. Problems of choosing a suitable bearing clearance, designing an optimum bush geometry, selecting a proper bush material are crucial for life time of the bearing. In particular the problem is in forming hydrodynamical properties of bearing as owing to its operation in the fluid friction regime durability of bearings, the very responsible units of propulsion transmission system, can be greatly extended.
Optimal design of sustainable cellulosic biofuel supply chains: Multiobjective optimization coupled with life cycle assessment and input–output analysis
Authors: You Fengqi , Tao Ling , Graziano Diane J. , Snyder Seth W. 
Published: March 2011

AbstractThis article addresses the optimal design and planning of cellulosic ethanol supply chains under economic, environmental, and social objectives. The economic objective is measured by the total annualized cost, the environmental objective is measured by the life cycle greenhouse gas emissions, and the social objective is measured by the number of accrued local jobs. A multiobjective mixed‐integer linear programming (mo‐MILP) model is developed that accounts for major characteristics of cellulosic ethanol supply chains, including supply seasonality and geographical diversity, biomass degradation, feedstock density, diverse conversion pathways and byproducts, infrastructure compatibility, demand distribution, regional economy, and government incentives. Aspen Plus models for biorefineries with different feedstocks and conversion pathways are built to provide detailed techno‐economic and emission analysis results for the mo‐MILP model, which simultaneously predicts the optimal network design, facility location, technology selection, capital investment, production planning, inventory control, and logistics management decisions. The mo‐MILP problem is solved with an ε‐constraint method; and the resulting Pareto‐optimal curves reveal the tradeoff between the economic, environmental, and social dimensions of the sustainable biofuel supply chains. The proposed approach is illustrated through two case studies for the state of Illinois. © 2011 American Institute of Chemical Engineers AIChE J, 2012
Proposed chronic cerebrospinal venous insufficiency criteria do not predict multiple sclerosis risk or severity
Authors: Centonze Diego , Floris Roberto , Stefanini Matteo , Rossi Silvia , Fabiano Sebastiano , Castelli Maura , Marziali Simone , Spinelli Alessio , Motta Caterina , Garaci Francesco G. , Bernardi Giorgio , Simonetti Giovanni 
Published: March 2011

AbstractObjective:It is still unclear whether chronic cerebrospinal venous insufficiency (CCSVI) is associated with multiple sclerosis (MS), because substantial methodological differences have been claimed by Zamboni to account for the lack of results of other groups. Furthermore, the potential role of venous malformations in influencing MS severity has not been fully explored. This information is particularly relevant, because uncontrolled surgical procedures are increasingly offered to MS patients to treat their venous stenoses.Methods:In the present study, CCSVI was studied in 84 MS patients and in 56 healthy subjects by applying the Zamboni method for CCSVI identification.Results:We found no significant differences (p = 0.12) in CCSVI frequency between MS and control subjects. Furthermore, no differences were found between CCSVI‐positive and CCSVI‐negative patients in terms of relevant clinical variables such as disease duration, time between onset and first relapse, relapsing or progressive disease course, and risk of secondary progression course. Statistically significant differences were not found between CCSVI‐positive and CCSVI‐negative MS subjects by analyzing direct measures of disability such as mean Expanded Disability Status Scale (EDSS) (p = 0.07), mean progression index (p > 0.1), and mean MS severity score (p > 0.1). The percentage of subjects who reached EDSS 4.0 and 6.0 milestones was not different among CCSVI‐negative and CCSVI‐positive subjects, and no significant correlation was found between severity of disability and number of positive CCSVI criteria.Interpretation:Our results indicate that CCSVI has no role in either MS risk or MS severity. Ann Neurol 2011;
Polyhedral oligomeric silsesquioxane–polyphenylsulfone nanocomposites: Investigation of the melt‐flow enhancement, thermal behavior, and mechanical properties
Authors: Jones Paul J. , Cook Robert D. , McWright Cynthia N. , Nalty Raymond J. , Choudhary Veena , Morgan Sarah E. 
Published: March 2011

AbstractTwo structurally and chemically different polyhedral oligomeric silsesquioxane (POSS) molecules with different solubility parameters, dodecaphenyl POSS and trisilanolphenyl POSS, were melt‐blended with polyphenylsulfone (PPSU), and the effects on the material processing, rheology, and thermomechanical properties were investigated. Process monitoring and capillary rheometry revealed enhancements in the processing melt flow and a reduction in the nanocomposite viscosity with only a small addition of POSS. The magnitude and concentration dependence of rheological modification were shown to depend on POSS structure. Although small increases in the tensile modulus were observed, reductions in the tensile elongation properties were observed at high POSS loading levels. Analysis of the nanocomposite fracture behavior and surface morphology provided evidence for the surface phase segregation of both types of POSS, but the extent of segregation was related to the POSS structure. The degree of interfacial adhesion in the POSS/polymer composites and the resultant rheological behavior were related to the POSS composition and predicted solubility parameters. No measurable effect on the glass‐transition temperature or molecular weight of PPSU was observed, whereas small improvements in the thermal degradation behavior were obtained with the incorporation of POSS. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
New polymers from epoxidized soybean oil with pyridine derivatives
Authors: Öztürk Cem , Küsefoğlu Selim H. 
Published: March 2011

AbstractIn this study 4‐methylpyridine (4MP), 4‐vinylpyridine (4VP) and poly(4‐vinylpyridine) (P4VP) were separately reacted with epoxidized soybean oil triglycerides (ESO) to give plant oil based thermoset polymers. The addition reaction of pyridine with epoxide followed by a rearrangement results in formation of pyridone units and these were polymerized via a Diels–Alder reaction. DMA, DSC, TGA and IR spectroscopy were used for the characterization of the products. 4MP‐ESO, P4VP‐ESO and P4VP‐ESO‐in situ polymers were crosslinked yielding rigid infusible polymers. Glass transition temperatures (Tg) of 4MP‐ESO and P4VP‐ESO‐in situ were found as −10.5 and 70.5 (32.3 as shoulder) °C respectively, by DMA analysis. Storage moduli of 4MP‐ESO and P4VP‐ESO‐in situ at 25°C were 13.7 and 187.2 MPa, respectively. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Preparation and surface activity of gelatin‐derived surfactants modified with polyoxyethylene stearyl ether units
Authors: Lin Li‐Huei , Lin Po‐Chang 
Published: March 2011

AbstractWe have prepared a series of novel gelatin derivatives through reactions of gelatin with alkyl succinic anhydride and polyoxyethylene stearyl ether. These derivatives contain gelatin units and polyoxyethylene chains as their hydrophilic moieties and alkyl succinic anhydrides and 18‐carbon‐atom alkyl chains as their hydrophobic moieties. Surface activities were evaluated in terms of the materials' surface tensions, wetting abilities, emulsifying powers, and foaming properties. The surface tensions were characterized with respect to the critical micelle concentration (cmc), the surface tension at the cmc, the maximum surface excess concentration, the standard free energy, and the surface area per molecule at the air‐water interface. The modified gelatins were more surface‐active relative to gelatin itself. Increasing the polyoxyethylene chain length led to a decrease in surface activity. The excellent foaming, wetting, and emulsifying behavior of the gelatin derivatives was a direct result of the presence of their multiple hydrophilic and hydrophobic units. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Synthesis and characterization of the polyaminophenol derivatives containing thiophene in side chain: Thermal degradation, electrical conductivity, optical‐electrochemical, and fluorescent properties
Authors: Kaya İsmet , Aydın Aysel 
Published: March 2011

AbstractNovel polyaminophenols, poly‐2‐[3‐thienylmethylene]aminophenol (P‐2,3‐TP), poly‐3‐[3‐thienylmethylene]aminophenol (P‐3,3‐TP) and poly‐4‐[3‐thienylmethylene]amino phenol (P‐4,3‐TP), were synthesized by oxidative polycondensation reaction. Metal complexes of P‐2,3‐TP were also obtained. The structures of synthesized compounds were confirmed by FT‐IR, UV‐vis, 1H NMR, and 13C NMR techniques. The characterization was made by TG‐DTA, DSC, and gel permeation chromatography (GPC) analyses in addition to solubility tests. Electrical conductivities of polymers were measured by four‐point probe technique. Fluorescence measurements were carried out in various solutions and optimum concentrations and maximal intensities were determined. The new synthesized polyaminophenols are good candidates for electronic, opto‐electronic, and photovoltaic applications due to polyconjugated structures. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
High‐energy heavy‐ion irradiation effects in makrofol‐KG polycarbonate and PET
Authors: Ramola R. C. , Negi Ambika , Semwal Anju , Chandra Subhash , Rana J. M. S. , Sonkawade R. G. , Kanjilal D. 
Published: March 2011

AbstractThis experimental study investigated the modification of optical, structural and morphological properties of Makrofol‐KG and Polyethylene Terephtalate (PET) by irradiation of 120 MeV Ni+9 ions at fluences ranging from 1 × 1010 to 1 × 1012 ion/cm2. Optical and structural properties were studied by UV–visible spectroscopy and X‐ray diffraction (XRD) method, respectively. XRD studies of pristine and irradiated polymers revealed that crystallinity decreased after irradiation with swift heavy ions. The UV–visible spectrum displayed a shift in absorbance edge toward higher wavelength at higher fluence, which can be correlated with transition involved in polymers. Fourier transform infrared spectroscopy spectra were analyzed to investigate the changes in the chemical/structural properties of these polymers. The Makrofol‐KG is found to exhibit more pronounced modification compared to PET after irradiation by swift heavy ions. The surface morphology studied by atomic force microscopy showed that the roughness of polymers surface increased with increasing fluence. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Higher clearance of micafungin in neonates compared with adults: role of age‐dependent micafungin serum binding
Authors: Yanni Souzan B. , Smith P. Brian , Benjamin Daniel K. , Augustijns Patrick F. , Thakker Dhiren R. , Annaert Pieter P. 
Published: March 2011

AbstractMicafungin, a new echinocandin antifungal agent, has been used widely for the treatment of various fungal infections in human populations. Micafungin is predominantly cleared by biliary excretion and it binds extensively to plasma proteins. Micafungin body weight‐adjusted clearance is higher in neonates than in adults, but the mechanisms underlying this difference are not understood. Previous work had revealed the roles of sinusoidal uptake (Na+‐taurocholate co‐transporting peptide, NTCP; organic anion transporting polypeptide, OATP) as well as canalicular efflux (bile salt export pump, BSEP; breast cancer resistance protein, BCRP) transporters in micafungin hepatobiliary elimination. In the present study, the relative protein expression of hepatic transporters was compared between liver homogenates from neonates and adults. Also, the extent of micafungin binding to serum from neonates and adults was measured in vitro. The results indicate that relative expression levels of NTCP, OATP1B1/3, BSEP, BCRP and MRP3 were similar in neonates and in adults. However, the micafungin fraction unbound (fu) in neonatal serum was about 8‐fold higher than in the adult serum (0.033±0.012 versus 0.004±0.001, respectively). While there was no evidence for different intrinsic hepatobiliary clearance of micafungin between neonates and adults, our data suggest that age‐dependent serum protein binding of micafungin is responsible for its higher clearance in neonates compared with adults. Copyright © 2011 John Wiley & Sons, Ltd.
Modelling of phenol biodegradation by Candida tropicalis immobilised in alginate gel beads
Authors: Jia Xiaoqiang , Wen Jianping , Ji Tao , Jiang Yan 
Published: March 2011

AbstractPhenol‐degrading yeast Candida tropicalis were immobilised in alginate gel beads and photographed by scanning electron microscopy. Batch phenol biodegradation experiments were done in shaking flasks under varying conditions such as initial phenol concentrations and bead loadings. A mathematical model was proposed to simulate the batch phenol biodegradation process in the immobilised system, which took into account the internal and external mass transfer resistances of phenol and oxygen and the double‐substrate phenol–oxygen intrinsic kinetics. The validation of this model was done by the comparison between the model simulations and the experimental measurements of phenol concentration profiles in the main liquid phase. Moreover, the time and radius courses of phenol, oxygen, and cell concentration profiles within the alginate gel beads were reasonably predicted by the proposed model.
A Literature Review on the Links between Environmental Regulation and Competitiveness
Authors: Iraldo Fabio , Testa Francesco , Melis Michela , Frey Marco 
Published: March 2011

ABSTRACTThe effects of environmental regulation on competitiveness are under constant debate for policy‐makers and practitioners. The following article reviews the different ways of defining and measuring the effects of environmental regulation on competition and market forces and synthesizes the most recent findings on the relationship between these dimensions. We find that two variables have proved to be both (1) key in defining to what extent and under what conditions environmental regulation exerts adverse or positive effects on competitiveness, and (2) difficult to nail down: forms of regulation and responses by business. The form of regulation may be as important as its stringency in determining the nature of its relationship with competitiveness. The relationship between environmental policies, environmental performance and competitiveness may also vary depending on the characteristics of the businesses and sectors concerned. Taking these factors in the methods of assessment into account may be crucial in understanding the nature of the relationship between environmental regulation and competitiveness. Copyright © 2011 John Wiley & Sons, Ltd and ERP Environment.
Electronic Band Structure, Optical Properties, and Photocatalytic Hydrogen Production of Barium Niobium Phosphate Compounds (BaO–Nb2O5–P2O5)
Authors: Cho In Sun , Kim Dong Wook , Kim Dong Hoe , Shin Seong Sik , Noh Tae Hoon , Kim Dong Wan , Hong Kug Sun 
Published: March 2011

AbstractBarium niobium phosphate compounds (BaNb2P2O11 and Ba3Nb2P4O18), with corner‐sharing NbO6 octahedra as well as PO4 tetrahedra, were prepared by a conventional solid‐state reaction method, and their optical properties, electronic band structure, and photocatalytic activity were investigated. The powders were characterized by X‐ray powder diffraction (XRD), field‐emission SEM (FESEM), high‐resolution TEM (HRTEM), and UV/Vis and fluorescence spectroscopy. Both compounds exhibit similar optical band gaps, 3.55 eV for BaNb2P2O11 and 3.58 eV for Ba3Nb2P4O18. However, photoluminescence spectra revealed that a radiative recombination process of charge carriers is dominant in Ba3Nb2P4O18 (strong blue‐white emission at 300 K) under UV irradiation, whereas no obvious emission was observed from BaNb2P2O11. The photocatalytic activity for the evolution of H2 from the splitting of pure water was evaluated. BaNb2P2O11, which has a smaller photon emission at room temperature, exhibited a much higher photocatalytic activity than Ba3Nb2P4O18. The difference in the photocatalytic activity of the two compounds is attributed to their different electronic band structures, resulting from their different crystal‐structure environments.
Synthesis and Derivatization of the Bis(amido)‐λ3‐cyclodiphosphazanes cis‐[R′(H)NP(μ‐NR)]2, Including a Rare Example, trans‐[tBu(H)N(Se)P(μ‐NCy)]2, Showing Intermolecular Se···H–O Hydrogen Bonding
Authors: Chandrasekaran P. , Mague Joel T. , Balakrishna Maravanji S. 
Published: March 2011

AbstractThe reaction of PCl3 with CyNH2 in a 1:3 ratio affordedthe dichloro‐λ3‐cyclodiphosphazane, cis‐[ClP(μ‐NCy)]2 (2), whereas the corresponding 1:5 reaction gave the bis(amido)‐λ3‐cyclodiphosphazane cis‐[Cy(H)NP(μ‐NCy)]2 (3) in quantitative yield. The dichloro derivative 2 was converted into 3 by reacting 2 with four equivalents of CyNH2. The mixed (amido)derivatives cis‐[tBu(H)NP(μ‐NCy)]2 (4) and cis‐[Cy(H)NP(μ‐NtBu)]2 (5) were prepared from the reaction of cis‐[ClP(μ‐NCy)]2 (2) and cis‐[ClP(μ‐NtBu)]2 (1a) with a fourfold excess of the respective primary amines. The oxidation of the bis(amido)‐λ3‐cyclodiphosphazanes 3–5 with two equivalents of H2O2/H2O, S8, and Se8 produced the bis(oxo) [R′(H)N(O)P(μ‐NR)]2 [R = R′ = Cy (6); R = tBu, R′ = Cy (7); R = Cy, R′ = tBu (8)], bis(sulfide) [R′(H)N(S)P(μ‐NR)]2 [R = R′ = Cy (9); R = tBu, R′ = Cy (10); R = Cy, R′ = tBu (11)], and bis(selenide) [R′(H)N(Se)P(μ‐NR)]2 [R = R′ = Cy (12); R = tBu, R′ = Cy (13); R = Cy, R′ = tBu (14)] derivatives, respectively. The reaction of cis‐[R(H)NP(μ‐NtBu)]2 with two equivalents of phosphoryl azide, [N3P(O)(OPh)2], afforded the corresponding bis(iminophosphoryl) derivatives, cis‐{R(H)N[(OPh)2P(O)N]P(μ‐NtBu)}2 [R = tBu (15), R = Ph (16), R = Cy (17)]. The solid‐state structures for 11, 12, 13, and 15 were determined by single‐crystal X‐ray diffraction studies. Interestingly, the bis(selenide) derivative [tBu(H)N(Se)P(μ‐NCy)]2 13 turned out be a trans isomer in the solid state, whereas the other cyclodiphosphazane derivatives exhibited the cis geometry. Compounds 13 and 15 crystallized along with a water molecule that facilitated the intermolecular Se···H–O and N···H–O hydrogen bonding, respectively, to form a linear 1D hydrogen bonding network.
Polydopamine as an adhesive coating for open tubular capillary electrochromatography
Authors: Martma Kert , Habicht Kaia‐Liisa , Ramirez Xochitl M. , Tepp Kersti , Käämbre Tuuli , Volobujeva Olga , Shimmo Ruth 
Published: March 2011

AbstractPolydopamine (PolyD) coating was used as an adhesive layer in the preparation of biological stationary phases for open tubular capillary electrochromatography (OT‐CEC). The influence of coating solution freshness, coating time, temperature and dopamine hydrochloride concentration on the PolyD layer formation was studied. The performance of the polyD coating was monitored by measuring the electro‐osmotic flow in coated capillaries. Following polyD coating of the capillary, secondary layer material (e.g. cell membrane solutions, phospholipid mixtures or mitochondria) was inserted into the capillary for at least 1 h. The performance of these double‐coated capillaries (a polyD layer+a biological material layer) was compared with capillaries containing the respective biological material directly attached to the capillary wall. The study reveals that the presence of polyD layer in fused silica capillaries improves the performance of lipid and membrane fragment coatings in capillaries. At the same time, the thickness of the polyD layer does not have marked impact on the secondary coatings. Analysis with test analytes demonstrated that double‐coated capillaries can be applied to study membrane–drug interactions.
Combinatorial peptide ligand libraries: The conquest of the ‘hidden proteome’ advances at great strides
Authors: Righetti Pier Giorgio , Fasoli Elisa , Boschetti Egisto 
Published: March 2011

AbstractThe combinatorial peptide ligand library (CPLL) is compared here with the immuno‐depletion method for evaluating their respective abilities in digging deeper and deeper into the low‐abundance proteome. A recent report suggested in fact that immuno‐subtraction for biomarkers discovery in sera does not perform so well, since it results in a meagre 25% increase in identified proteins compared with unfractionated plasma, leaving little capacity to sample lower abundance proteins. On the contrary, CPLLs permit from 300 to 600% increments in detection abilities, as amply demonstrated in several reports. Moreover, when dealing with large sample volumes, an amplification factor of up to four orders of magnitude for trace proteins could be demonstrated, with 80% capture efficiencies even in large (up to 1 L) sample volumes. At present, the lower detection ability of CPLLs has been evaluated at 1 ng/mL (traces of casein additives in white wines).
SIMPLE‐H: a finite‐volume pressure–enthalpy coupling scheme for flows with variable density
Authors: Emans M. , Frolov Sergey M. , Lidskii B. , Posvyanskii V. , Basara B. 
Published: March 2011

SUMMARYWe present a method that simultaneously solves the pressure‐correction equation and the energy equation in a conventional SIMPLE scheme. In comparison to other techniques, the new method leads to a remarkable reduction in the number of required iterations, in particular for problems characterized by significant temperature gradients. It is shown that this translates to very attractive computing times. Copyright © 2011 John Wiley & Sons, Ltd.