bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Crystalline Catalyst Based on a Porous Metal‐Organic Framework and 12‐Tungstosilicic Acid: Particle Size Control by Hydrothermal Synthesis for the Formation of Dimethyl Ether
Authors: Liang Da‐Dong , Liu Shu‐Xia , Ma Feng‐Ji , Wei Feng , Chen Ya‐Guang 
Published: March 2011

AbstractThe strategy for obtaining a crystalline catalyst based on a porous copper‐based metal‐organic framework and 12‐tungstosilicic acid with different particle sizes is reported. Through the control of hydrothermal synthesis and some simple treatments, catalyst samples with average particle diameters of 23, 105, and 450 μm, respectively, were prepared. This crystal catalyst has both the Brønsted acidity of 12‐tungstosilicic acid and the Lewis acidity of the copper‐based metal‐organic framework, and has high density of accessible acid sites. Its catalytic activity was fully assessed in the dehydration of methanol to dimethyl ether. The effect of particle size on the catalytic activity of catalyst was studied, in order to select the particle size appropriate for avoiding the diffusion limitation in heterogeneous gas‐phase catalysis. In the selective dehydration of methanol to dimethyl ether, this catalyst exhibited higher catalytic activity than the copper‐based metal‐organic framework, γ‐alumina, and γ‐alumina‐supported 12‐tungstosilicic acid catalysts. It showed high catalytic performances, even at higher space velocity or in the presence of excess water. In addition, the catalyst was also preliminarily assessed in the formation of ethyl acetate from acetic acid and ethylene. It also exhibited a high activity which was comparable with that of silica‐supported 12‐tungstosilicic acid catalyst.
Gold‐Catalyzed Cyclizations: A Comparative Study of ortho,ortho′‐Substituted KITPHOS Monophosphines with their Biaryl Monophosphine Counterpart SPHOS
Authors: Hashmi A. Stephen K. , Loos Annette , Doherty Simon , Knight Julian G. , Robson Katharine J. , Rominger Frank 
Published: March 2011

AbstractElectrophilic gold(I) triflimide (trifluoromethanesulfonimide) complexes of electron‐rich ortho,ortho′‐disubstituted KITPHOS (11‐dicyclohexylphosphino‐12‐phenyl‐9,10‐ethenoanthracene) monophosphines are efficient catalysts for intramolecular cycloisomerizations that afford phenols, 3‐acylindenes and methylene‐oxazolines; comparative catalyst testing showed that these catalysts either competed with or outperformed that based on SPHOS [2‐(2′,6′‐dimethoxybiphenyl)dicyclohexylphosphine]. An electron‐rich biarylmonophosphine containing a single ortho‐methoxy substituent, prepared by rhodium‐catalyzed [2+2+2] cycloaddition between a 1‐alkynyl(dicyclohexylphosphine) oxide and 1,7‐octadiyne, also formed a highly efficient catalyst for the same transformations. Monitoring of comparative catalyst testing between a KITPHOS‐based gold(I) triflimide complex containing a coordinated tetrahydrothiophene and its counterpart coordinated solely by the triflimide anion revealed that the former is an order of magnitude less efficient than the latter, confirming that tetrahydrothiophene can be an effective catalyst inhibitor.
The use of fractional exhaled nitric oxide in investigation of work‐related cough in a hairdresser
Authors: Pala Gianni , Pignatti Patrizia , Moscato Gianna 
Published: March 2011

AbstractBackgroundOccupational and environmental factors may be a cause of nonasthmatic eosinophilic bronchitis (NAEB). The diagnosis of occupational NAEB requires evidence of sputum eosinophilia. Nevertheless, a minority of patients are not able to produce suitable sputum specimens.MethodsThis case report describes a 25‐year‐old woman, working as a hairdresser since the age of 20 years and handling ammonium persulfate, who came under our observation for work‐related rhinitis and cough.ResultsA specific inhalation challenge with ammonium persulfate elicited dry cough, without any significant change in forced expiratory volume in 1 s (FEV1). Sputum induction was unsuccessful both pre‐ and after specific inhalation challenge. Fractional exhaled nitric oxide (FeNO) values significantly increased after specific inhalation challenge, suggesting a diagnosis of occupational NAEB due to ammonium persulfate.ConclusionsFrom this observation we suggest that FeNO measurement should be added to the investigation of work‐related cough during specific inhalation challenge, and may be considered as an alternative to induced sputum to evaluate bronchial inflammation when sputum collection is unavailable or unsuccessful. Am. J. Ind. Med. 54:565–568, 2011. © 2011 Wiley‐Liss, Inc.
TiO2 Nanotubes: Synthesis and Applications
Authors: Roy Poulomi , Berger Steffen , Schmuki Patrik 
Published: March 2011

AbstractTiO2 is one of the most studied compounds in materials science. Owing to some outstanding properties it is used for instance in photocatalysis, dye‐sensitized solar cells, and biomedical devices. In 1999, first reports showed the feasibility to grow highly ordered arrays of TiO2 nanotubes by a simple but optimized electrochemical anodization of a titanium metal sheet. This finding stimulated intense research activities that focused on growth, modification, properties, and applications of these one‐dimensional nanostructures. This review attempts to cover all these aspects, including underlying principles and key functional features of TiO2, in a comprehensive way and also indicates potential future directions of the field.
Modeling of solid–liquid equilibria for polyethylene and polypropylene solutions with equations of state
Authors: Costa G. M. N. , Kislansky S. , Oliveira L. C. , Pessoa F. L. P. , Vieira de Melo S. A. B. , Embiruçu M. 
Published: March 2011

AbstractWe modeled solid–liquid equilibria (SLEs) in polyethylene and polypropylene solutions with a Soave–Redlich–Kwong (SRK) cubic equation of state (EOS) and a perturbed‐chain statistical associating fluid theory (PC‐SAFT) EOS. Two types of mixing rules were used with SRK EOS: The Wong–Sandler mixing rule and the linear combination of the Vidal and Michelsen mixing rules (LCVM), both of which incorporated the Bogdanic and Vidal activity coefficient model. The performance of these models was evaluated with atmospheric‐pressure and high‐pressure experimental SLE data obtained from literature. The basic SLE equation was solved for the equilibrium melting temperature instead of for the composition. The binary interaction parameters of SRK and PC‐SAFT EOS were estimated to best describe the experimental equilibrium behavior of 20 different polymer–solvent systems at atmospheric pressure and 31 other polymer–solvent systems at high pressure. A comparison with experimental data showed that SRK–LCVM agreed very well with the atmospheric SLE data and that PC‐SAFT EOS was more efficient in high‐pressure conditions. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Biodegradable blends based on chitin and chitosan: Production, structure, and properties
Authors: Rogovina Svetlana Z. , Alexanyan Christine V. , Prut Eduard V. 
Published: March 2011

AbstractBlends based on LDPE and chitin or chitosan were prepared under high‐temperature shear deformations in a rotor disperser at different initial ratios of the components. Although one of the components is an infusible polymer (polysaccharide), the powder blends were obtained. The composition of the powder fractions was shown to be identical to the original blend composition. It was found that the addition of poly(ethylene oxide) to the mentioned blends improves the biodegradability of the polymer materials and extends their application areas. Using various physicochemical methods, the structural and morphological changes in the polymer compositions under the action of shear deformations were examined, the mechanical characteristics of prepared films were determined, and also the features of their bio‐, thermo‐, and photo‐oxidative degradation were studied. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Properties of n‐eicosane‐loaded silk fibroin‐chitosan microcapsules
Authors: Basal Guldemet , Sirin Deveci Senem , Yalcin Dilek , Bayraktar Oguz 
Published: March 2011

AbstractPCM microcapsules containing n‐eicosane were prepared by complex coacervation of silk fibroin (SF) and chitosan (CHI). Chemical characterization of microcapsules was carried out using Fourier‐transform infrared (FT‐IR) spectroscopy. Thermal properties and thermal stability of microencapsulated n‐eicosane were determined by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). FTIR spectra confirmed the encapsulation of n‐eicosane within the microcapsules. Results from thermal analyses showed that microcapsules consisted of an average of 45.7 wt % n‐eicosane, and had a thermal energy storage and release capacity of about 93.04 J/g and 89.68 J/g, respectively. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Electrical conductivity and mechanical strength of composites consisting of phenolic resin, carbon fibers, and metal particles
Authors: Simitzis J. , Zoumpoulakis L. , Soulis S. , Triantou D. , Pinaka Ch. 
Published: March 2011

AbstractComposites of phenolic resin of novolac type as matrix, with metal particles of Zn as conducting filler, without or with 15% v/v carbon fibers were manufactured by hot pressing. The porosity ratio, the hardness, the flexural and shear strength, and the electrical conductivity of the composites were determined. The percolation threshold was determined based on two models of electrical conductivity versus the content of metal particles of Zn, namely, an analogous to polymer gelation model and the other based on the power law. The composites of carbon fibers combined with Zn particles have higher electrical conductivity than the corresponding without carbon fibers and high strength, lower than that of the composite reinforced with carbon fibers without Zn particles, but still acceptable. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Maleic anhydride copolymers with ability to bind metal ions. 1. polydentate amine derivatives for cr (III) ions' removal
Authors: Albu Ana Maria , Mocioi Mihaela , Mateescu Carmencita Doina , Iosif Andreea 
Published: March 2011

AbstractNew polymeric chelate structures derived from maleic anhydride–dicyclopentadiene copolymer (MA–DCPD) were synthesized by chemical modifications with triethylenetetramine (TETA), from Riedel De Haën AG Seelze, Hannover. Germany. Both amide and imide forms of these new polymers have been tested in the retention process of Cr (III) ions. Experimental results referring mainly to the retention capacity and retention efficiency, for different values of the working parameters: contact procedure, batch time, concentration of chelators, and pH, are presented. The polymer structures and their metal complexes were characterized by IR spectroscopy. IR spectra proved that the metal was coordinated by nitrogen from TETA. The thermal properties of modified polymers and polychelates were also examined. Based on these experimental results and literature data, we discuss a possible binding mechanism and suggest the polychelate structures. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Bonding characteristics of recycled polyethylene terephthalate (PET) fibers coated with maleic anhydride grafted polypropylene in cement‐based composites
Authors: Won Jong‐Pil , Park Chan‐Gi , Lee Su‐Jin , Kang Joo‐Won 
Published: March 2011

AbstractIn this study, we sought to enhance the bond performance between recycled polyethylene terephthalate(PET) fibers and cement‐based composites using a hydrophilization treatment with hydrophilic maleic anhydride grafted polypropylene (mPP). The bond performance was evaluated with bone‐shaped specimens after the hydrophilization treatment. The effects of the concentration of mPP in the solution in which the PET fibers were immersed (0, 5, 10, 15, and 20%) and the three types of shapes on the surface energy of the recycled PET fibers were evaluated. The pullout behavior, bond strength, and interfacial energy all increased with the concentration of mPP to 15% but decreased at 20%. This occurred because 15% mPP coated the recycled PET fiber thoroughly, whereas a 20% mPP coating resulted in partial cracks, which led to fractures on application of a pullout load. Of the fiber shapes, the embossed fibers demonstrated the best bond behavior. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Cytological features of atypical carcinoid combined with adenocarcinoma of the uterine cervix
Authors: Hara Hitoshi , Ishii Eri , Honda Tomomi , Nakagawa Miki , Teramoto Katsuhiro , Oyama Toshio 
Published: March 2011

AbstractNeuroendocrine tumors of the uterine cervix (UC) are rare, and atypical carcinoid (AC) combined with adenocarcinoma of the uterine cervix (ACAUC) is particularly rare. Only the histopathology has been investigated in the English literature. A 49‐year‐old female with a polypoid lesion of the UC visited Yamanashi Prefectural Central Hospital. Scraping cytology, biopsy, and hysterectomy was performed. EC smears showed solid, rosette, honeycomb, true tubular, and trabecular clusters. Solid clusters were oval, thin edge, delicate, small‐large nuclei, pale, granular, scant, nothing, and well‐preserved (though ill‐defined border) cytoplasm. Rosette clusters were eccentric, oval nuclei, mixture of coarsely granular chromatin and euchromatin, and cyanophilic luminal content. Solid and rosette clusters impress AC. Honeycomb clusters involved a clearly defined border and translucent mucin. True tubular clusters were oval nuclei of fine chromatin or euchromatin, thick cytoplasm, and orange luminal content. Honeycomb and true tubular clusters suspected adenocarcinoma. Trabecular clusters were fusiform, columnar, cuboidal, and polygonal cell shapes of small, monotonous nuclei, and contained coarsely granular chromatin with occasionally intracytoplasmic translucent mucin and were difficult to differentiate typical carcinoid and adenocarcinoma. Histology was AC combined with adenocarcinoma. The aim of this study was to investigate the cytological characteristics of ACAUC. Diagn. Cytopathol. 2012. © 2011 Wiley Periodicals, Inc.
The Mechanism of the Acid‐Catalyzed Benzidine Rearrangement of Hydrazobenzene: A Theoretical Study
Authors: Ghigo Giovanni , Osella Silvio , Maranzana Andrea , Tonachini Glauco 
Published: March 2011

AbstractThe acid‐catalyzed benzidine rearrangement of hydrazobenzene yields p‐benzidine and diphenyline as the main products and some other secondary products such as o‐benzidine, o‐semidine and p‐semidine. Several reaction mechanisms have been proposed for this rearrangement, but none fully describes it. In this work we present the results of an unrestricted DFT(M06‐2X) study in which the benzidine rearrangement of the hydrazobenzene is fully described. Some relevant points were also analyzed with the CASSCF and CASPT2 methods. Our theoretical approach properly describes the electronic structure of all species along the reaction pathway. The rearrangement of the hydrazobenzene has been found to take place through a multi‐step mechanism in which complexes with dication diradical character similar to those proposed by Dewar play a key role. For the first time, the kinetic isotope effects have been calculated and were found to be in good agreement with the experimental findings. The relative yields of the main products were also correctly estimated. Finally, an explanation of the general acid catalysis observed in some experiments is offered.
Access to the cis‐Fused Stereoisomers of Proline Analogues Containing an Octahydroindole Core
Authors: Sayago Francisco J. , Laborda Pedro , Calaza M. Isabel , Jiménez Ana I. , Cativiela Carlos 
Published: March 2011

AbstractAn overview of the synthetic methods developed to build all the cis‐fused stereoisomers of octahydroindole‐2‐carboxylic acid and its α‐methylated derivative in enantiomerically pure form is presented. Both asymmetric synthetic strategies(auxiliary‐ or substrate‐controlled processes) and procedures based on the resolution of racemic compounds (chemical, enzymatic, and chromatographic processes) are summarized. Special emphasis has been placed on those strategies able to provide multigram quantities of enantiopure compounds, a prerequisite to make downstream biological applications feasible.
Intermolecular Amination of Allyl Alcohols with Sulfamates: Effective Utilization of Mercuric Catalyst
Authors: Yamamoto Hirofumi , Ho Elisabeth , Sasaki Ikuo , Mitsutake Mizuho , Takagi Yuichi , Imagawa Hiroshi , Nishizawa Mugio 
Published: March 2011

AbstractHerein, we describe the intermolecular amination of allyl alcohols with sulfamates, which have been underutilized as nitrogen nucleophiles for allylic amination. Methyl sulfamate is a good nucleophile in the presence of mercuric triflate and efficiently generates monoallylation products in excellent yield at room temperature. Furthermore, the solid‐supported mercuric catalyst silaphenyl mercuric triflate also showed remarkable catalytic activity for the allylic amination.
Quantification of plasma lactate concentrations using capillary electrophoresis with contactless conductivity detection
Authors: Pormsila Worapan , Morand Réjane , Krähenbühl Stephan , Hauser Peter C. 
Published: March 2011

AbstractThe quantification of plasma lactate and evaluation of the lactate threshold by CE with capacitively coupled contactless conductivity is demonstrated. The only sample preparation needed was deproteinization with a ACN/methanol mixture. A solution of 10 mmol/L 2‐morpholinoethanesulfonic acid monohydrate, 10 mmol/L DL‐histidine, 70 μmol/L hexadecyltrimethylammonium bromide, pH 6.0 was found suitable as running buffer. Linearity was achieved for the concentration range of 10–1000 μmol/L with a correlation coefficient of 0.9994. The limit of detection (3 S/N) was determined as 3.2 μmol/L. Intra‐ and inter‐day variabilities were less than 7% RSD. The suitability of the method could be demonstrated by analyzing various clinical samples, where the results correlated satisfactorily with those of an established enzymatic method.
Automated microsystem for electrochemical detection of cancer markers
Authors: Kellner Christian , Botero Mary Luz , Latta Daniel , Drese Klaus , Fragoso Alex , O'Sullivan Ciara K. 
Published: March 2011

AbstractThe development of a fully automated microsystem housing an amperometric immunosensor is presented. The microfluidic cell integrates reagent storage and electrochemical immunodetection and was applied for the detection of breast cancer markers. The main advantage of this system is that no external fluidic storage is required and the instrumental setup is thus greatly simplified. The fluidics of the microsystem is computer controlled and requires minimal end‐user intervention. The analytical performance of the device was compared with a manually driven system and applied for the amperometric detection of the carcinoembryonic antigen (CEA) and cancer antigen 15‐3 (CA15‐3). This automation methodology greatly improves the analytical performance of the immunosensor in terms of accuracy and reproducibility as evidenced by a reduction of LOD observed for CEA and CA15‐3 with respect to a manually driven system. Finally, the automated microsystem was applied for the analysis of real patient serum samples, demonstrating excellent correlation with a commercial ELISA.
Effect of temperature and organic loading rate on upflow anaerobic sludge blanket reactor and CH4 production by treating liquidized food waste
Authors: Latif M.A. , Ahmad A. , Ghufran R. , Wahid Z.A. 
Published: March 2011

AbstractAnaerobic treatment of liquidized food waste (LFW) was carried out in an upflow anaerobic sludge blanket reactor (UASBR) by stepwise increase in organic loading rate (OLR) and temperature. The chemical oxygen demand (COD), total organic carbon (TOC), biogas and methane production were measured at hydraulic retention time (HRT) of 10 to 4d, and start up strategy of the reactor was monitored for 10 weeks. Thermophilic condition was achieved by increasing the temperature from 30 to 55°C, and pH was maintained at 7 ± 0.5 throughout the experiment. Maximum COD removal efficiency was 93.67% (r = 0.84) at an OLR of 12.5 g‐COD/L·d and 4d HRT. Maximum TOC removal efficiency was 79.14% (r = −0.94) at an influent TOC concentration of 3.59 g/L. Biogas and methane yield were recorded to a maximum of 1.364 L/g‐CODremoved·d (r = 0.81), 0.912 L/g‐CODremoved·d (r = 0.83), and average methane content of biogas was 63%. The reactor was fully acclimatized at 55°C and achieved stability with high removal efficiency and biogas production. An OLR of 12.5 g‐COD/L·d and HRT of 4 days were suitable for the treatment of LFW in UASBR. The treatment process can also be extendable for more than 10 weeks without any measurable problem. © 2011 American Institute of Chemical Engineers Environ Prog, 2012
Chronic perchlorate exposure causes morphological abnormalities in developing stickleback
Authors: Bernhardt Richard R , von Hippel Frank A , O'Hara Todd M 
Published: March 2011

Abstract
Few studies have examined the effects of chronic perchlorate exposure during growth and development, and fewer still have analyzed the effects of perchlorate over multiple generations. We describe morphological and developmental characteristics for threespine stickleback (Gasterosteus aculeatus) that were spawned and raised to sexual maturity in perchlorate-treated water (G1,2003) and for their offspring (G2,2004) that were not directly treated with perchlorate. The G1,2003 displayed a variety of abnormalities, including impaired formation of calcified traits, slower growth rates, aberrant sexual development, poor survivorship, and reduced pigmentation that allowed internal organs to be visible. Yet these conditions were absent when the offspring of contaminated fish (G2,2004) were raised in untreated water, suggesting a lack of transgenerational effects and that surviving populations may be able to recover following remediation of perchlorate-contaminated sites. Environ. Toxicol. Chem. 2011; 30:1468–1478. © 2011 SETAC
Selenium concentrations and enzyme activities of glutathione metabolism in wild long-tailed ducks and common eiders
Authors: Franson J. Christian , Hoffman David J , Flint Paul L 
Published: March 2011

Abstract
The relationships of selenium (Se) concentrations in whole blood with plasma activities of total glutathione peroxidase, Se-dependent glutathione peroxidase, and glutathione reductase were studied in long-tailed ducks (Clangula hyemalis) and common eiders (Somateria mollissima) sampled along the Beaufort Sea coast of Alaska, USA. Blood Se concentrations were &gt;8 µg/g wet weight in both species. Linear regression revealed that the activities of total and Se-dependent glutathione peroxidase were significantly related to Se concentrations only in long-tailed ducks, raising the possibility that these birds were experiencing early oxidative stress. Environ. Toxicol. Chem. 2011; 30:1479–1481. © 2011 SETAC
Forecasting Performance of Nonlinear Models for Intraday Stock Returns
Authors: Matías José M. , Reboredo Juan C. 
Published: March 2011

ABSTRACTWe studied the predictability of intraday stock market returns using both linear and nonlinear time series models. For the S&P 500 index we compared simple autoregressive and random walk linear models with a range of nonlinear models, including smooth transition, Markov switching, artificial neural network, nonparametric kernel regression and support vector machine models for horizons of 5, 10, 20, 30 and 60 minutes. The empirical results indicate that nonlinear models outperformed linear models on the basis of both statistical and economic criteria. Specifically, although return serial correlation receded by around 10 minutes, return predictability still persisted for up to 60 minutes according to nonlinear models, even though profitability decreases as time elapses. More flexible nonlinear models such as support vector machines and artificial neural network did not clearly outperform other nonlinear models. Copyright © 2011 John Wiley & Sons, Ltd.