bluuebunny/crossref_metadata_2025 huggingface dataset:
Deposition Voltage Research of CdSe Quantum Dots Sensitized TiO2 Solar Cell
Authors: Zhao Liu Ying , Zhou Fu Fang , Hu Peng , Han Song Jie , Wang Ping
Published: July 2015

TiO2nanocrystalline semiconductor film was made on the titanium (Ti) substrate by hydrothermal method,and then prepared the CdSe quantum dot layer on the face of the TiO2nanocrystalline semiconductor film by electrochemical deposition method. We studied the affect of deposition voltage of the CdSe quantum dots’ growth, finding that when the deposition voltage was-1.3V,CdSe quantum dots grown best.However, In terms of CdSe/TiO2as the light-anode,using electricity chemistry workstation to test,We gain a solar cell with Short circuit current density of 1.45×10-3A·cm-2and the open circuit voltage of 0.24 V.
Pd/SiO2 Organic-Inorganic Hybrid Materials by Sol-Gel Method: Preparation and Thermal Stability under H2 Atmosphere
Authors: Yang Jing , Li Bao Song , Huo Xiang , Xu Hao , Hou Hai Yun
Published: July 2015

Pd/SiO2 organic-inorganic hybrid materials were prepared by adding PdCl2 into methyl-modified silica sol. The Pd/SiO2 hybrid materials were characterized by X-ray diffraction (XRD), fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS). The effects of calcination temperature and Pd-doping on the phase transition of Pd element and the thermal stability of CH3 group in the Pd/SiO2 organic-inorganic hybrid materials were investigated. The results showed that the reduced metallic Pd0 exhibits good thermal stability under H2 atmosphere in the calcination process. Pd element in noncalcined Pd/SiO2 materials exists in PdCl2 form, calcination at 200 °C in a H2 atmosphere produces some metallic Pd0 and calcinations at 350 °C results in the complete transformation of Pd2+ to metallic Pd0. With the increase of calcination temperature, the Pd0 particle sizes increase and the hydrophobic Si−CH3 bands decrease in intensity. As the calcination temperature is greater than or equal to 350 °C, the loading of metallic Pd0 nearly has no influence on the chemical structure but, with the increase of Pd content, the formed Pd0 particle size increases. To keep the hydrophobicity of Pd/SiO2 membrane materials, the optimal calcination temperature is about 350 °C under H2 atmosphere.
The Influence of Yb3+/Er3+ Co-Doped β-NaYF4 Up-Conversion Micron Tubes on Photocatalytic Activity of TiO2 for Degradation of Organic Dyes
Authors: Ma Yuan Liang , Zheng Xue Rong , Liu Wei , Li Hai Qin , Ji Hui Ming
Published: July 2015

Pure phase of Yb3+/Er3+ co-doped β-NaYF4 micron tubes with up-conversion fluorescence were synthesized by hydrothermal method at 180°C for 24 hours. For better utilization of sunlight and improving photocatalytic efficiency of organic dyes, TiO2 nanoparticles were modified by combining with β-NaYF4 micron tubes to form TiO2/NaYF4 composite. Three different combination methods were studied and the photocatalytic activities of the corresponding samples were tested by measuring the degradation rate of rhodamine aqueous solution under illumination of simulated sunlight. The composite that TiO2 nanoparticles were well dispersed on the surface of NaYF4 shows better photocatalytic activity than other composites and was near twice efficiency of pure TiO2 nanoparticles. The reason may be due to the high activity of heterostructure for TiO2/NaYF4 composite that will make it easy for sunlight absorption and photocatalytic degradation.
Influence of Calcination Temperature on the Performance of TiO2 Films in Dye-Sensitized Solar Cells
Authors: Wang Yan Xiang , Ye Yu Hong , Sun Jian , Shi Yan Tao
Published: July 2015

In this work, the effects of calcination temperature on the photovoltaic performance of TiO2 films prepared with non-hydrolytic sol-gel method were reported. The optimal photovoltaic performance of DSCs was obtained by annealing TiO2 film at 550 °C. The short-circuit current (Jsc), open-circuit voltage, fill factor (FF) and energy conversion efficiency were 15.68 mA·cm-2, 0.71 V, 0.62 and 6.83%, respectively.
Dynamic Analysis of Delaminated Beams
Authors: Mahieddine Ali , Ouali Mohammed , Mazouz Amel
Published: July 2015

To investigate the dynamic behavior of beams with partially delaminated layers, a model is presented in this work. This model takes into account the lateral strains. The principal advantage of the element is that it allows the modeling of delamination anywhere in the structure. The region without delamination is modeled to carry constant peel and shear stresses. Numerical results of the present model are presented and its performance is evaluated.
Wood Dimensional Changes due to Hygrothermal Behaviour
Authors: de Freitas V.P. , Delgado João M.P.Q. , Machado N.
Published: July 2015

Wood has a strong hygroscopic behaviour, with a strong variation of moisture content and dimension stability caused by modifications of the relative humidity of the surrounding air. The properties that define the behaviour of wood facing temperature and moisture actions were studied in this work. Linear thermal expansion, hygroscopicity, shrinkage (tangential and radial shrinkage coefficient) and hygric expansion were given special attention.An experimental device was designed for testing wood samples, red oak. A series of tests was performed including the determination of hygric expansion coefficient and the definition of the sorption curve. This research made possible the evaluation of dimensional stability of wood in transient conditions of relative humidity.
Application of Artificial Neural Network for Prediction of Boride Layer Depth Obtained on XC38 Steel in Molten Salts
Authors: Rayane Karim , Allaoui Omar
Published: July 2015

This paper discusses an application of neural network system on the performance of boride layer thickness. Boriding treatment was carried out in three different molten salts consisting of borax (Na2B4O7) added to boron carbide (B4C), aluminum (Al) and silicon carbides (SiC). The substrate used in this study was XC38 steel. Borides layers involved in this work was obtained from a boriding treatment at the temperature range of 800-1050 °C with 50°C interval for 2, 4 and 6 h. A numerical experiment using normalized and binarized values was carried out, using a back-propagation algorithm in ANN. The modeling shows that for the three bath the depth of boride layer was predicted with good accuracy, with a highest performance of normalized values along experimental data range.
Towards a Study of Effects on Hydrogen Diffusion into T40 Titanium Alloys
Authors: Dejardin Steeve , Duquesnes Vincent , Creton Nicolas , Bezverkhyy Igor , Montesin Tony , Oltra Roland
Published: July 2015

In a global study of titanium alloys behavior in specific aqueous solution (embrittlement, corrosion and corrosion under stresses), the present work focuses on hydrogen diffusion into the metal and the consequences on its microstructure. Two ways of hydrogen charging were used to investigate this issue (gaseous and cathodic charging). The final aim is to determine a fitted method to create an identified microstructure and then to perform accelerated aging tests of titanium U-Bend samples into an autoclave with a specific environment. Hydrogen absorption and formation of titanium hydride have been studied by SEM analyses and by X-ray diffraction methods.
Characterisation of Defects in ZnO Implanted by Hydrogen
Authors: Procházka Ivan , Čížek Jakub , Valenta Jan , Havránek Vladimír , Hruška Petr , Novotný Michal , Lančok Ján
Published: July 2015

In the present work, defects created by implantation of hydrothermally grown ZnO single crystals of high quality with H+ions were investigated by positron annihilation lifetime (LT) spectroscopy combined with measurements of optical transmittance (OT) and photoluminescence (PL). First, zinc vacancies attached with one hydrogen impurity (VZn– 1H) atom were identified in the virgin ZnO single crystal. The ZnO single crystals were then bombarded by H+ions with the energy of 2.5 MeV to the fluence of 1016cm-2. It was found that VZn– VOdivacancies were introduced into ZnO by H+-implantation. Effects of H+-implantation on the optical activity of defects in ZnO lattice are characterised in the light of the present OT and PL data.
Dynamic Model of Carbon Fiber Drive Shaft
Authors: Dąbrowski Zbigniew , Deuszkiewicz Piotr
Published: July 2015

The main goal of this paper is, that if we want to correctly identify dynamic model of drive shaft made of carbon-epoxy composite, we must take into account the influence of deformation velocity on elasticity characteristic. In the paper, Authors showed the effect of passing shaft resonance (1st critical speed). It was shown in the conditions of acceleration and braking with different increases of rotational speed. When examining the results obtained with empirical and model research, it has been shown that in the structural design of carbon fiber drive shafts, the main factor affecting the right development of the structure should be dynamic criterion, since the only use of static criteria leads to big errors.
Digitalna pismenost in reševanje problemov v tehnološko bogatih okoljih
Authors: Dolničar Vesna , Mrzel Maja
Published: July 2015

Hiter razvoj in vedno večja vloga informacijsko-komunikacijskih tehnologij zahtevata bolj razvite digitalne spretnosti posameznikov. Prispevek se osredotoča na koncepta digitalnih spretnosti in reševanja problemov v tehnološko bogatih okoljih, ki bosta obravnavana tudi na podlagi empiričnih podatkov, pridobljenih v mednarodni študiji PIAAC. V uvodnem delu je podan pregled literature in so predstavljeni rezultati predhodnih raziskav s področja merjenja digitalnih spretnosti ter podatki o uporabi storitev informacijske družbe med članicami Evropske unije. V drugem delu članka analiziramo rezultate, pridobljene v študiji PIAAC. Ti rezultati so pokazali, da imata največji vpliv na uspešnost reševanja problemov v tehnološko bogatih okoljih starost in izobrazba, kar potrjujejo tudi rezultati drugih raziskav. Prispevek zaključujemo s predlogi za izboljšanje trenutnega stanja vključenosti vseh skupin prebivalstva v programe usposabljanja na področju digitalnih spretnosti.
Vpliv izobrazbe in spretnosti starejših na individualno in družbeno blaginjo
Authors: Kump Sonja
Published: July 2015

Prispevek izhaja iz nekaterih teoretskih razmislekov o starosti in staranju, ki se pojavljajo v razpravah o izobraževanju starejših. Temu sledi predstavitev mednarodnih dokumentov, v katerih je izobraževanje povezano z aktivnim življenjem starejših, ter nekaterih ugotovitev raziskav, ki poudarjajo velik pomen izobraževanja starejših za blaginjo na individualni in družbeni ravni. V nadaljevanju so analizirani podatki raziskave PIAAC o vplivu izobrazbe in spretnosti na področju aktivnega državljanstva, socialne kohezije in osebnega razvoja. Posebej so v ospredju podatki, ki se nanašajo na vzorec starostne skupine 55–65 let v izbranih državah. Ugotovitve analize potrjujejo povezavo med stopnjo izobrazbe in spretnosti starejših odraslih ter individualno in družbeno blaginjo v večini izbranih držav, čeprav je povezanost v nekaterih državah močnejša.
Miniestaquia de Sapium glandulatum (Vell.) Pax com o uso de ácido indol butírico e ácido naftaleno acético.
Authors: Ferreira Bárbara Guerreira Alpande , Zuffellato-Ribas Katia Christina , Wendling Ivar , Koehler Henrique Soares , Nogueira Antonio Carlos
Published: July 2015

Sapium glandulatum (Vell.) Pax. (Euphorbiaceae) é uma árvore nativa de vários biomas brasileiros, com grande interesse para a recuperação de ecossistemas degradados devido a sua rusticidade. Entretanto, sua propagação sexuada apresenta dificuldades devido, principalmente, a pouca produção de sementes, baixa taxa de germinação e grande quantidade de flores masculinas. A miniestaquia constitui uma alternativa para a propagação da espécie, a qual pode fornecer material juvenil favorável ao enraizamento. Esta pesquisa teve como objetivo avaliar o enraizamento e a produção de miniestacas por minicepa provenientes de mudas originadas por via seminal, coletadas nas quatro estações do ano (inverno, primavera, verão de 2006 e outono de 2007), no município de Colombo - PR, Brasil. As miniestacas foram confeccionadas com 3-5 cm de comprimento e um par de folhas na porção apical, com sua área reduzida pela metade. Estas foram submetidas a tratamentos com o uso dos reguladores vegetais ácido indol butírico (IBA) e ácido naftaleno acético (NAA). Os reguladores foram utilizados na forma de solução por 10 segundos nas bases das miniestacas em concentrações de 0, 2000, 4000, 6000, 8000 mgL-1. Foram avaliados o percentual de miniestacas enraizadas, o número e comprimento das raízes formadas, o percentual de miniestacas com calos, a sobrevivência e mortalidade, em um delineamento experimental inteiramente casualizado com arranjo fatorial 2x5x4 (tipos de reguladores vegetais x concentrações dos reguladores vegetais x estações do ano). A produção de miniestacas por minicepa a cada coleta variou de 1,4 a 2,2 em recipientes contendo 205 cm3. A estação do inverno mostrou-se promissora para o enraizamento adventício de miniestacas, apresentando 80,56% sem a aplicação dos reguladores vegetais sendo, portanto, desnecessária a aplicação destes para a indução radicial. Desta forma, a técnica de miniestaquia de propágulos oriundos de mudas produzidas por semente é viável e pode ser recomendada para o enraizamento da espécie.
Geoprocessamento como ferramenta de apoio à gerência de pavimentos em estradas florestais.
Authors: Emmert Fabiano , Pereira Reginaldo Sérgio , Rezende Alba Valéria , Encinas José Marcelo Imañas
Published: July 2015

O objetivo do trabalho foi utilizar as técnicas de geoprocessamento na aquisição, manipulação, espacialização e visualização de dados do padrão de qualidade de estradas florestais, e na confecção de mapas temáticos, com a identificação de pontos críticos para o transporte de madeira, servindo como subsídio para o desenvolvimento de um programa de manutenção preventivo e regular. Identificaram-se e avaliaram-se a integridade e as condições de operação de estradas florestais mediante levantamento contínuo de defeitos na superfície de rolamento e obtenção do ICRNP (índice de condição da rodovia não-pavimentada). A base de dados georreferenciada, a alocação das unidades amostra e a espacialização da rede viária foram obtidas com auxílio da imagem do satélite CBERS II, modelo de elevação do terreno SRTM, e GPS. A identificação e a avaliação das rodovias, por meio de levantamentos detalhados em campo, demonstraram as condições da superfície de rolamento das rodovias, gerando informações sobre os trechos mais críticos e a intensidade de cada defeito, apontando ainda ações e base de custos para manutenção das estradas florestais. As técnicas de geoprocessamento, GPS, sensoriamento remoto e SIG mostraram-se como eficientes ferramentas para a interpretação, qualificação e quantificação de fenômenos naturais da região de estudo e para auxílio na gerência de pavimentos das estradas florestais. O SIG integrou os dados referentes aos padrões de operação e manutenção das rodovias à base de dados georreferenciada, manipulando, espacializando e disponibilizando visualmente, por meio de mapas, as informações geradas.
Rigidez e resistência de vigas estruturais de madeira laminada colada e com perfil I compostas por diferentes adesivos.
Authors: Cunha Alexsandro Bayestorff da , Matos Jorge Luis Monteiro de
Published: July 2015

A madeira sempre foi utilizada estruturalmente na construção civil na forma sólida, com baixo grau de processamento e inovação tecnológica e, muitas vezes, em outros componentes como em pisos, paredes e telhados. Entretanto, a mudança nos padrões adotados envolveu o aperfeiçoamento da tecnologia, bem como a mudança do conceito estético e funcional requerido nas construções. Dessa forma, surgiram as vigas estruturais em madeira como a Madeira Laminada Colada (MLC) e com Perfil em I que apresentam uma série de vantagens como à alta resistência em relação ao seu peso. O objetivo geral do presente estudo foi avaliar o efeito do tipo de adesivo sobre a resistência e rigidez de vigas estruturais de Madeira Laminada Colada (MLC) e com perfil em I de Pinus taeda. Os adesivos utilizados no experimento foram a Resorcina Fenol Formaldeído (RFF), a Melamina Uréia Formaldeído (MUF) e o Poliuretano (PUR). O processo de fabricação das vigas envolveu a classificação das peças, fabricação de emendas, junção, montagem e prensagem. Os ensaios envolveram a avaliação das propriedades estruturais sob flexão como Módulo de Elasticidade (MOE) e Ruptura (MOR). Na análise dos valores médios obtidos para as variáveis não foram encontradas diferenças significativas para as vigas de MLC, entretanto, nas vigas com perfil em I, verificouse a superioridade do adesivo PUR no valor médio do MOR. Em relação aos tipos e gramaturas de adesivos utilizados, observou-se que o adesivo RFF necessita de maior quantidade do produto para atender ao mecanismo da adesão, 500 g/m2. Dois parâmetros tornaram o adesivo PUR diferenciado em relação aos demais; o tempo de cura 24 vezes mais rápido, tornando-o mais vantajoso sob o ponto de vista de volume de produção e o tempo em aberto mais curto que requer procedimentos especiais. As vigas de MLC apresentaram valores médio superiores, mas a escolha do modelo de viga deve ser analisada cuidadosamente, levando-se sempre em consideração a resistência requerida e o custo do material a ser utilizado na confecção destas.
Estructura poblacional de Myrocarpus frondosus Allemão en un bosque en galería de la Selva Paranaense en Misiones, Argentina
Authors: Caldato Silvana Lucia , Pezzutti Raúl Vicente
Published: July 2015

Para describir la estructura poblacional de Myrocarpus frondosus Allemão fue estudiada una población de la especie, caracterizando los estadios de tamaño y la distribución espacial de los individuos, en un bosque en galería de la Selva Paranaense en Misiones, Argentina, a 27º39'00" S y 55º44'30" O. La especie fue estudiada en parcelas circulares. En las parcelas fueron considerados todos los individuos de Myrocarpus frondosus con diámetro DAP (a 1,3 metros de altura) mayor o igual a 10 cm para el estrato arbóreo y para la regeneración natural fueron considerados los plantines de la especie con DAP variando de 2 cm hasta 9,9 cm. Fueron encontrados 396 individuos (431 ind. ha-1), de los cuales 180 pertenecieron al estrato arbóreo y 216 correspondieron a la regeneración natural. Los resultados muestran que la amplitud de tamaño en diámetro varió desde 2 cm hasta 50 cm, con una distribución de la población estudiada en forma de J invertida, representando una población con substancial reclutamiento de individuos en sus primeras etapas de desarrollo. La especie presentó un patrón agrupado de distribución espacial.
Avaliação da regeneração natural em nascentes perturbadas no município de Lavras, MG.
Authors: Ferreira Marciel José , Pereira Israel Marinho , Botelho Soraya Alvarenga , Mello Carlos Rogério de
Published: July 2015

Este trabalho teve como objetivo avaliar a dinâmica da regeneração natural em duas nascentes em processo de recuperação no município de Lavras, MG. Para tanto, foram realizados dois inventários após o isolamento das áreas, nos períodos de Agosto/2005 (18 meses) e Abril/2006 (24 meses). Foram alocadas no total 122 parcelas de 5´5 m (25 m2), sendo 76 na nascente 1 e 46 parcelas na nascente 2. As parcelas foram distribuídas de forma sistemática ao longo de toda a área das nascentes. Todos os indivíduos com altura superior a 0,10 m e DAP (diâmetro a altura do peito) < 5 cm, foram identificados, tendo seus diâmetros e alturas mensuradas. Foram avaliadas a composição florística, a estrutura, e a dinâmica da regeneração natural. Foram amostrados no total 524 indivíduos pertencentes a 24 famílias e 55 espécies. A família Asteraceae se destacou em número de espécies na nascente 1 e as famílias Fabaceae Faboideae, Myrtaceae e Solanaceae na nascente 2. As espécies Baccharis dracunculifolia e Vernonia ferruginea apresentaram os maiores índices de regeneração natural, na nascente 1, enquanto que as espécies Vernonia polyanthes e Nectandra nitidula se destacaram na nascente 2. O maior índice de diversidade foi registrado para a nascente 2 na segunda avaliação, aumentando de 3,324 (primeira avaliação) para 3,384 (segunda avaliação). O índice de similaridade florística encontrado entre as duas nascentes, foi de 20,0 e 18,5% para as avaliações 1 e 2 respectivamente. Durante o período de monitoramento, verificou-se um aumento significativo de 33,33 e 15,8% no número de indivíduos amostrados nas nascentes 1 e 2 respectivamente. O método da regeneração natural apresenta grande potencial para a recuperação da vegetação no entorno das duas nascentes, sendo necessária, no entanto, a adoção de técnicas de controle do capim Brachiaria sp.
Propriedades físico-mecânicas de painéis aglomerados produzidos com diferentes proporções de madeira e casca de arroz
Authors: Melo Rafael Rodolfo de , Santini Elio José , Haselein Clovis Roberto , Stangerlin Diego Martins
Published: July 2015

No presente trabalho, avaliaram-se as propriedades físico-mecânicas de painéis aglomerados produzidos com diferentes proporções de madeira (Eucalyptus grandis) e casca de arroz. Para caracterização dos painéis produzidos com os adesivos ureia-formaldeído e tanino-formaldeído, nas proporções 0, 20, 40, 60, 80 e 100% de casca de arroz, determinaram-se as propriedades físicas (massa específica; teor de umidade; absorção de água e inchamento em espessura após 2 e 24 horas de imersão em água), e de resistência mecânica (flexão estática; ligação interna e arrancamento de parafusos). Os resultados obtidos indicaram que o acréscimo da casca de arroz proporcionou uma maior instabilidade e uma menor resistência das chapas. Quando confeccionados utilizando a resina à base de tanino, os painéis apresentaram qualidade superior.
Local trend disparities of European minimum and maximum temperature extremes
Authors: Franzke Christian L. E.
Published: July 2015

Ecosystems and societies are highly vulnerable to extreme temperatures and to changes in the range of temperatures at local scales. Here I will show how trends in warm and cold extremes have evolved over the last six decades in Europe on local scales. Comparing the slopes of two extreme quantiles demonstrates that there are significant disparities in trends of cold and warm temperature extremes at many locations in Europe. At some locations the range of extreme cold and hot temperatures increases, while at other locations it decreases. These results suggest that at some locations both warm and cold extremes intensify which seems to be contradictory to the prevailing view of global warming in which both cold and warm temperatures are expected to increase.
A Comparative Study of the Effects of Nontoxic Chloride Treatments on CdTe Solar Cell Microstructure and Stoichiometry
Authors: Williams Benjamin L. , Major Jonathan D. , Bowen Leon , Keuning Wytze , Creatore Mariadriana , Durose Ken
Published: July 2015

This work presents the first systematic comparison of the effects of a range of chlorides (CdCl2, MgCl2, NaCl, and NH4Cl) on the microstructure and chemical composition of CdTe/CdS/ZnO/SnO2 solar cells, providing valuable insight to the ubiquitous Cl‐activation process. Using X‐ray diffraction, it is shown that CdCl2 induces the greatest extent of recrystallization (standard deviation of texture coefficients, σ, reduces from 0.93 for as‐grown CdTe to 0.43) and minimizing stress (from 178 MPa for as‐grown material to zero). MgCl2 treatment also yields significant randomization of the CdTe texture (σ = 0.55) but NaCl treatment does not (σ = 1.10). A strong correlation between the extent of metallurgical changes induced by the chloride treatment (and consequently, device efficiency) and the dissociation energy of the cationCl bond is shown, thereby accounting for the ineffectiveness of NaCl (bond energy = 4.3 eV). From this, a mechanism for Cl activation is postulated. By X‐ray photoelectron spectroscopy it is also shown that the Te/Cd ratio at the back surface, and the Cl content at the CdTe–CdS interface, are both higher following CdCl2‐ and MgCl2 treatments (Te/Cd = 1.3–1.4, and 1–2 at% Cl) than following NaCl treatment (Te/Cd = 1.1, and 0 at% Cl).
Carboxymethylcellulose‐supported palladium nanoparticles generated in situ from palladium(II) carboxymethylcellulose as an efficient and reusable catalyst for ligand‐ and base‐free Heck–Matsuda and Suzuki–Miyaura couplings
Authors: Xiao Jinlong , Lu Zhangxiu , Li Zhipeng , Li Yiqun
Published: July 2015

A novel palladium(II) carboxymethylcellulose (CMC‐PdII) was prepared by direct metathesis from sodium carboxymethylcellulose and PdCl2 in aqueous solution. Its catalytic activities were explored for Heck–Matsuda reactions of aryldiazonium tetrafluoroborate with olefins, and Suzuki–Miyaura couplings of aryldiazonium tetrafluoroborate with arylboronic acid. Both reactions proceeded at room temperature in water or aqueous ethanol media without the presence of any ligand or base, to provide the corresponding cross‐coupling products in good to excellent yields under atmospheric conditions. The CMC‐PdII and carboxymethylcellulose‐supported palladium nanoparticles (CMC‐Pd0) formed in situ in the reactions were characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, inductively coupled plasma atomic emission spectrometry, and scanning and transmission electron microscopies. The homogeneous nature of the CMC‐Pd0 catalyst was confirmed via Hg(0) and CS2 poisoning tests. Moreover, the CMC‐Pd0 catalyst could be conveniently recovered by simple filtration and reused for at least ten cycles in Suzuki–Miyaura reactions without apparently losing its catalytic activity. The catalytic system not only overcomes the basic drawbacks of homogeneous catalyst recovery and reuse but also avoids the need to fabricate palladium nanoparticles in advance. Copyright © 2015 John Wiley & Sons, Ltd.
Lubricin Restoration in a Mouse Model of Congenital Deficiency
Authors: Hill Adele , Waller Kimberly A. , Cui Yajun , Allen Justin M. , Smits Patrick , Zhang Ling X. , Ayturk Ugur M. , Hann Steven , Lessard Samantha G. , Zurakowski David , Warman Matthew L. , Jay Gregory D.
Published: July 2015

Objective

Congenital deficiency of the principal boundary lubricant in cartilage (i.e., lubricin, encoded by the gene PRG4) increases joint friction and causes progressive joint failure. This study was undertaken to determine whether restoring lubricin expression in a mouse model would prevent, delay, or reverse the disease process caused by congenital deficiency.

Methods

Using genetically engineered lubricin‐deficient mice, we restored gene function before conception or at ages 3 weeks, 2 months, or 6 months after birth. The effect of restoring gene function (i.e., expression of lubricin) on the tibiofemoral patellar joints of mice was evaluated histologically and by ex vivo biomechanical testing.

Results

Restoring gene function in mice prior to conception prevented joint disease. In 3‐week‐old mice, restoring gene function improved, but did not normalize, histologic features of the articular cartilage and whole‐joint friction. In addition, cyclic loading of the joints produced fewer activated caspase 3–containing chondrocytes when lubricin expression was restored, as compared to that in littermate mice whose gene function was not restored (nonrestored controls). Restoration of lubricin expression in 2‐month‐old or 6‐month‐old mice had no beneficial effect on histopathologic cartilage damage, extent of whole‐joint friction, or activation of caspase 3 when compared to nonrestored controls.

Conclusion

When boundary lubrication is congenitally deficient and cartilage becomes damaged, the window of opportunity for restoring lubrication and slowing disease progression is limited.
Study of fluorescence interaction and conformational changes of bovine serum albumin with histamineH1‐receptor–drug epinastine hydrochloride by spectroscopic and time‐resolved fluorescence methods
Authors: Ariga Girish G. , Naik Praveen N. , Nandibewoor Sharanappa T. , Chimatadar Shivamurti A.
Published: July 2015

The fluorescence, ultraviolet (UV) absorption, time resolved techniques, circular dichroism (CD), and infrared spectral methods were explored as tools to investigate the interaction between histamine H1drug, epinastine hydrochloride (EPN), and bovine serum albumin (BSA) under simulated physiological conditions. The experimental results showed that the quenching of the BSA by EPN was static quenching mechanism and also confirmed by lifetime measurements. The value ofnclose to unity indicated that one molecule of EPN was bound to protein molecule. The binding constants (K) at three different temperatures were calculated (7.1 × 104, 5.5 × 104, and 3.9 × 104M−1). Based on the thermodynamic parameters (ΔH0,ΔG0, andΔS0), the nature of binding forces operating between drug and protein was proposed. The site of binding of EPN in the protein was proposed to be Sudlow's site I based on displacement experiments using site markers viz, warfarin, ibuprofen, and digitoxin. Based on the Förster's theory of non‐radiation energy transfer, the binding average distance, r between the donor (BSA) and acceptor (EPN) was evaluated and found to be 4.48 nm. The UV–visible, synchronous fluorescence, CD, and three‐dimensional fluorescence spectral results revealed the changes in secondary structure of the protein upon its interaction with EPN. © 2015 Wiley Periodicals, Inc. Biopolymers 103: 646–657, 2015.
The Effect of C4H and C5H on the Microstructure of Aqueous Solutions of 1‐Alkyl‐3‐methylimidazolium Tetrafluoroborate Ionic Liquids
Authors: Xu Yingjie , Li Haoran
Published: July 2015

As is well‐known, the C2H proton of 1‐ethyl‐3‐methylimidazolium tetrafluoroborate ([Emim]BF4) and 1‐butyl‐3‐methylimidazolium tetrafluoroborate ([Bmim]BF4) has a strong ability to form hydrogen bonds. The purpose of this work is to evaluate the effect of the interactions of the C4H and C5H protons on the microstructure of [Emim]BF4 and [Bmim]BF4 with water by using 1H NMR spectroscopy. The differences between the relative 1H NMR chemical shifts of C2H, C4H, and C5H and between the interaction‐energy parameters obtained from these chemical shifts are minor, thus suggesting that the interactions of C4H and C5H may have a considerable effect on the microstructure. To confirm this, the viscosities of the systems are estimated by using the interaction‐energy parameters obtained from the 1H NMR chemical shifts of the three studied aromatic protons and water, showing that the interactions of C4H and C5H also play an important role in the microstructure.
Two‐level consistent splitting methods based on three corrections for the time‐dependent Navier–Stokes equations
Authors: Liu Qingfang , Hou Yanren , Wang Zhiheng , Zhao Jiakun
Published: July 2015

Three kinds of two‐level consistent splitting algorithms for the time‐dependent Navier–Stokes equations are discussed. The basic technique of two‐level type methods for solving the nonlinear problem is first to solve a nonlinear problem in a coarse‐level subspace, then to solve a linear equation in a fine‐level subspace. Hence, the two‐level methods can save a lot of work compared with the one‐level methods. The approaches to linearization are considered based on Stokes, Newton, and Oseen corrections. The stability and convergence demonstrate that the two‐level methods can acquire the optimal accuracy with the proper choice of the coarse and fine mesh scales. Numerical examples show that Stokes correction is the simplest, Newton correction has the best accuracy, while Oseen correction is preferable for the large Reynolds number problems and the long‐time simulations among the three methods. Copyright © 2015 John Wiley & Sons, Ltd.
New Insights into the Mechanism of Reduction of Tertiary Phosphine Oxides by Means of Phenylsilane
Authors: Demchuk Oleg M. , Jasiński Radomir , Pietrusiewicz K. Michał
Published: July 2015

The mechanism of the reduction of phosphine oxides by PhSiH3 was established on the basis of kinetic measurements and Density Functional Theory (DFT) calculations. In particular, it has been proved that the model reaction between tri‐n‐butylphosphine oxide and phenylsilane occurs via a nonpolar mechanism. The data presented herein allow prediction and verification of the applicability of the new reduction reagents and conditions for industrially attractive processes.
In vitro cytotoxicity of superparamagnetic iron oxide nanoparticles on neuronal and glial cells. Evaluation of nanoparticle interference with viability tests
Authors: Costa Carla , Brandão Fátima , Bessa Maria João , Costa Solange , Valdiglesias Vanessa , Kiliç Gözde , Fernández‐Bertólez Natalia , Quaresma Pedro , Pereira Eulália , Pásaro Eduardo , Laffon Blanca , Teixeira João Paulo
Published: July 2015

Superparamagnetic iron oxide nanoparticles (ION) have attracted great interest for use in several biomedical fields. In general, they are considered biocompatible, but little is known of their effects on the human nervous system. The main objective of this work was to evaluate the cytotoxicity of two ION (magnetite), coated with silica and oleic acid, previously determining the possible interference of the ION with the methodological procedures to assure the reliability of the results obtained. Human neuroblastoma SHSY5Y and glioblastoma A172 cells were exposed to different concentrations of ION (5–300 µg ml–1), prepared in complete and serum‐free cell culture medium for three exposure times (3, 6 and 24 h). Cytotoxicity was evaluated by means of the MTT, neutral red uptake and alamar blue assays. Characterization of the main physical–chemical properties of the ION tested was also performed. Results demonstrated that both ION could significantly alter absorbance readings. To reduce these interferences, protocols were modified by introducing additional washing steps and cell‐free systems. Significant decreases in cell viability were observed for both cell lines in specific conditions by all assays. In general, oleic acid‐coated ION were less cytotoxic than silica‐coated ION; besides, a serum‐protective effect was observed for both ION studied and cell lines. These results contribute to increase the knowledge of the potential harmful effects of ION on the human nervous system. Understanding these effects is essential to establish satisfactory regulatory policies on the safe use of magnetite nanoparticles in biomedical applications. Copyright © 2015 John Wiley & Sons, Ltd.
Correction of the FSHD myoblast differentiation defect by fusion with healthy myoblasts
Authors: Dib Carla , Saada Yara Bou , Dmitriev Petr , Richon Catherine , Dessen Philippe , Laoudj‐Chenivesse Dalila , Carnac Gilles , Lipinski Marc , Vassetzky Yegor S.
Published: July 2015

Facioscapulohumeral dystrophy (FSHD) is a neuromuscular disease with a prevalence that could reach 1 in 8,000 characterized by progressive asymmetric muscle weakness. Myoblasts isolated from FSHD muscles exhibit morphological differentiation defects and show a distinct transcription profile. These abnormalities may be linked to the muscle weakness in FSHD patients. We have tested whether fusion of FSHD myoblasts with primary myoblasts isolated from healthy individuals could correct the differentiation defects. Our results show that the number of hybrid myotubes with normal phenotype increased with the percentage of normal myoblasts initially cultured. We demonstrated that a minimum of 50% of normal nuclei is required for a phenotypic correction of the FSHD phenotype. Moreover, transcriptomic profiles of phenotypically corrected hybrid myotubes showed that the expression of deregulated genes in FSHD myotubes became almost normal. The number of deregulated pathways also decreased from 39 in FSHD myotubes to one in hybrid myotubes formed with 40% FSHD and 60% normal myoblasts. We thus propose that while phenotypical and functional correction of FSHD is feasible, it requires more than 50% of normal myoblasts, it creates limitations for cell therapy in the FSHD context. J. Cell. Physiol. 230: 62–71, 2016. © 2015 Wiley Periodicals, Inc.
Regioselective Diastereomeric Michael Adducts as Building Blocks in Heterocyclic Synthesis
Authors: El‐Hashash Maher A. , Rizk Sameh A.
Published: July 2015

The reaction of 4‐(4‐acetylamino/bromophenyl)‐4‐oxobut‐2‐enoic acids with carbon nucleophiles afforded Michael adducts depending on the type of nucleophilic reagents and medium (acidic or basic). The adducts 2 and 3 were used as key starting materials to synthesize some heterocyclic compounds, which include pyridazinone, furanone, 1,2‐oxazin‐5‐one, 1.2‐diazapine, pyrane, and hydroxyl pyridine derivatives. The Steric factor plays an important role in regioselectivity. The structure of newly synthesized compounds was elucidated by elemental analysis and spectroscopic data.
On the Tensile Properties of Polylactide (PLA)/Arenga Pinnata “Ijuk” Fibre Composite
Authors: Chalid M. , Rahman Arif , Ferdian R. , Nofrijon  , Priyono B.
Published: July 2015

Composite as a plastic material derivative was widely used in various facets of life. Problems arising from the use of these common materials, among others, lies in the processing of components' waste that has reached the end of its life span. Through the use of polymeric materials derived from natural materials, namely poly lactic acid / polylactide (PLA), as well as reinforcing material prepared from natural fibers such asArenga pinnata/ ijuk fibers, polymer composites was made by hot compression molding (hot pressing). Chemical treatments with sodium hydroxide (NaOH) with a set treatment time and concentration were conducted on short fibres to improve compatibility with the matrix. Moreover, the effect of variation of volume fraction will be observed in the form of reinforcement levels (10, 20, and 30% of the total weight of starting material) on the properties (tensile strength, modulus of elasticity, elongation) of the resulting composites. The properties in question are tensile properties, and fibre – matrix compatibility. It was expected that the treatment would bring positive effect to the mechanical properties of composite and compatibility of fibre and matrix compared to the ones without treatment.
Fabricating polypyrrole/tungsten oxide hybrid based electrochromic devices using different ionic liquids
Authors: Dulgerbaki Cigdem , Oksuz Aysegul Uygun
Published: July 2015

A facile approach of polypyrrole (PPy)/tungsten oxide (WO3) composites electrosynthesized in ionic liquids for fabrication of electrochromic devices is discussed. The electrochromic properties of PPy/tungsten oxide nanocomposite films (PPy/WO3) prepared in the presence of four different ionic liquids, 1‐butyl‐3‐methylimidazolium tetrafluoroborate (BMIMBF4), 1‐butyl‐3‐methylimidazolium hexafluorophosphate (BMIMPF6), 1‐butyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl) imide (BMIMTFSI), and 1‐butyl‐1‐methylpyrrolidinium bis(trifluoromethylsulfonyl) imide (BMPTFSI) were investigated in detail. Cyclic voltammetry results revealed that PPy/WO3 nanocomposite films have much more electrochemical activity than those of WO3 and PPy film. The electrochromic contrast, coloration efficiency, and switching speed of the composite films were determined for electrochromic characteristics. The maximum contrast and the maximum coloration efficiency values were measured as 33.25% and 227.89 cm2/C for the PPy/WO3/BMIMTFSI composite film. Copyright © 2015 John Wiley & Sons, Ltd.
Spintronics with graphene quantum dots
Authors: Droth Matthias , Burkard Guido
Published: July 2015

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Thanks to its intrinsic ability to preserve spin coherence, graphene is a prime material for spintronics. In this review article, we summarize recent achievements related to spintronics in graphene quantum dots and motivate this field from a spintronics and a materials science point of view. We focus on theory but also discuss recent experiments. The main sources of spin decoherence are interactions with lattice excitations and the hyperfine interaction with present nuclear spins. We explain effective spin–phonon coupling in detail and present a generic power law for the spin relaxation time T1 as a function of the magnetic field. For specific cases, we discuss spin relaxation in detail. The Heisenberg exchange interaction is paramount for coherent spin qubit operation and addressed in the context of magnetism in graphene nanoflakes. Nuclear spins in the host and surrounding material can be considered by several means and the influence of 13C nuclei has been studied in detail. Impressive advances in general spintronics and the fabrication of graphene devices are likely to spark significant advances in spintronics with graphene quantum dots in the near future.

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(© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)
Multi‐Responsive Wormlike Micelles Based on N‐alkyl‐N‐Methylpiperidinium Bromide Cationic Surfactant
Authors: Yan Zhihu , Dai Caili , Zhao Mingwei , Zhao Guang , Li Yuyang , Wu Xuepeng , Liu Yifei , Du Mingyong
Published: July 2015

A noncovalent bonding method was utilized for forming multiresponsive surface‐active ionic liquids in mixed N‐alkyl‐N‐methylpiperidinium bromide (C16MDB) and potassium phthalic acid (PPA). Rheology, cryogenic‐transmission electron microscopy, dynamic light scattering and nuclear magnetic resonance were used to investigate the aggregation property of surface‐active ionic liquids in aqueous solution. The efficiency of the shielding effect in the form of hydrophobic effects and electrostatic attraction between PPA and the C16MDB headgroup under diverse pH conditions is found to be the root cause of a shift in the aggregate's morphological transformation. In addition, the molecular motion of surfactant molecules becomes more active as the temperature increase provides the property of thermoresponsive to the surface‐active ionic liquid system.
Single‐Leg Squat Performance is Impaired 1 to 2 Years After Hip Arthroscopy
Authors: Charlton Paula C. , Bryant Adam L. , Kemp Joanne L. , Clark Ross A. , Crossley Kay M. , Collins Natalie J.
Published: July 2015

Objective

To evaluate single‐leg squat performance 1‐2 years after arthroscopy for intra‐articular hip pathology compared with control subjects and the nonsurgical limb, and to investigate whether single‐leg squat performance on the operated limb was associated with hip muscle strength.

Design

Cross‐sectional study.

Setting

Private physiotherapy clinic and university laboratory.

Participants

Thirty‐four participants (17 women, 36.7 ± 12.6 years) 1‐2 years after hip arthroscopy and 34 gender‐matched control subjects (17 women, 33.1 ± 11.9 years).

Methods

Participants performed single‐leg squats using a standardized testing procedure. Squat performance was captured using video. Video footage was uploaded and reformatted for analyses. Hip muscle strength was measured with handheld dynamometry using reliable methods.

Outcome Measures

Frontal plane pelvic obliquity, hip adduction, and knee valgus were measured. Repeated measures analysis of variance evaluated between‐group differences, with limb as a within‐subjects factor (surgical versus nonsurgical) and gender as a between‐subjects factor (P < .05).

Results

The hip arthroscopy group demonstrated significantly greater apparent hip adduction (mean difference 2.7°, 95% confidence interval [CI] 0.7°‐4.8°) and apparent knee valgus (4.0°, 95% CI 1.0°‐7.1°) at peak squat depth compared with control subjects. The operated limb also demonstrated significantly greater pelvic obliquity during single‐leg stance compared with the nonsurgical limb (1.2°, 95% CI 0.1°‐2.3°). Women had significantly greater apparent hip adduction (standing 1.6°, 95% CI 0.5°‐2.6°; peak squat depth 2.4°, 95% CI 0.3°‐4.4°) and apparent knee valgus (standing 3.3°, 95% CI 1.8°‐4.7°; peak squat depth 3.1°, 95% CI 0°‐6.1°). Significant positive correlations were found between frontal plane angles and hip flexor and extensor peak torque (P > .05).

Conclusion

One to 2 years after hip arthroscopy, deficits in single‐leg squat performance exist that have the potential to increase hip joint impingement and perpetuate postoperative symptoms. Rehabilitation after hip arthroscopy should target retraining in functional single‐leg positions.
Variation in Rehabilitation Treatment Patterns for Hip Fracture Treated With Arthroplasty
Authors: Siebens Hilary C. , Sharkey Phoebe , Aronow Harriet U. , Deutscher Daniel , Roberts Pamela , Munin Michael C. , Radnay Craig S. , Horn Susan D.
Published: July 2015

Background

Recommendations for health care redesign often advocate for comparative effectiveness research that is patient‐centered. For patients who require rehabilitation services, a first step in this research process is to understand current practices for specific patient groups.

Objective

To document in detail the physical and occupational therapy treatment activities for inpatient hip fracture rehabilitation among 3 patient subgroups distinguished by their early rate of functional recovery between time of surgery to rehabilitation admission.

Design

Multicenter prospective observational cohort, practice‐based evidence, study.

Setting

Seven skilled nursing facilities and 11 inpatient rehabilitation facilities across the United States.

Participants

A total of 226 patients with hip fractures treated with hip arthroplasty.

Methods

Comparisons of physical and occupational therapy treatment activities among 3 groups with different initial recovery trajectory (IRT) rates (slower, moderate, faster).

Main Outcome Measure(s)

Percent of patients in each IRT group exposed to each physical and occupational therapy activity (exposure), and mean minutes per week for each activity (intensity).

Results

The number of patients exposed to different physical or occupational therapy activities varied within the entire sample. More specifically, among the 3 IRT groups, significant differences in exposure occurred for 44% of physical therapy activities and 39% of occupational therapy activities. More patients in the slower recovery group, IRT 1, received basic activities of daily living treatments and more patients in the faster recovery group, IRT 3, received advanced activities. The moderate recovery group, IRT 2, had some treatments similar to IRT 1 group and others similar to IRT 3 group.

Conclusions

Analyses of practice‐based evidence on inpatient rehabilitation of hip fracture patients treated with arthroplasty identified differences in therapy activities among three patient groups classified by IRT rates. These results may enhance physiatrists', other physicians', and rehabilitation teams' understanding of inpatient rehabilitation for these patients and help design future comparative effectiveness research.