bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ersatzneubau der Kajen im Marinestützpunkt Wilhelmshaven
Authors: Sunderdiek Hinnerk , Eickmeyer Dirk , Jäppelt Ulrich 
Published: September 2016

AbstractIm Marinestützpunkt Wilhelmshaven werden zurzeit die Kajenwände sowie die Dalben einer Schwimmbrückenanlage erneuert. Die vorhandenen Kajen weisen umfangreiche Schäden und Standsicherheitsdefizite auf. Insbesondere führte mikrobiell induzierte Korrosion (MIC) auf der Rückseite der alten Spundwände zu Durchrostungen an den alten Spundwänden.Inhalt des Berichts ist die planerische und bauliche Umsetzung der seit Anfang 2013 in der Bauausführung befindlichen Kajenerneuerung. Dabei wird insbesondere auf die Sicherung des Bestands während der Bauzeit, die gewählten Korrosionsschutzmaßnahmen sowie die Anforderungen an den Einbau der kombinierten Spundwände eingegangen.
The Silica‐based Formulations for Drug Delivery, Bone Treatment, and Bone Regeneration
Authors: Chowdhury Mohammad A. 
Published: September 2016

AbstractThe utilization of the silica‐based materials in biomedical applications is evolving at a rapid pace with attentions mostly devoted to the ordered mesoporous silica nanoparticles (MSNs). However, apart from the ordered‐MSNs, a range of other silica‐based materials have been extensively applied in the controlled release (CR) of drugs, bone treatments, and bone regeneration, but have gained less attention. This article presents an overview on the recent research advancements of the silica‐based materials, i.e., silica xerogels, silica microspheres, silica hybrids, silica microcapsule particles, silica ceramics, silica bioactive glasses, and silica beads which are mainly used in CR of drugs, bone disease treatments, and bone regeneration. The in vitro and in vivo biological evaluations on these silica‐based materials for antibacterial properties, osteoblast cell activities, osteogenetic performances, cell adhesion and proliferation, bio‐mineralization, and material degradation are discussed. The effect of morphology or surface modifications and addition of bone morphogenetic proteins to the silica‐based formulations are illustrated.
Three‐Dimensional Analytical Surface Quantification of Heterogeneous Silica‐Alumina Catalyst Supports
Authors: Roiban Lucian , Ersen Ovidiu , Hirlimann Charles , Drillon Marc , Chaumonnot Alexandra , Lemaitre Laurent , Gay Anne‐Sophie , Sorbier Loïc 
Published: September 2016

AbstractThe ability of energy‐filtered transmission electron microscopy (EFTEM) tomography to provide 3 D chemical maps at the nanoscale opens a new way to analyse heterogeneous materials quantitatively. In association with other techniques, EFTEM tomography has been employed in the study of amorphous silica‐alumina catalyst supports. Two types of samples prepared either by mechanical mixing (MM) or by the precipitation of silica on boehmite (PSB) that have similar proportions of silica and alumina were analysed. The sample synthesised by the PSB method shows a smaller degree of heterogeneity than the sample obtained by MM. For both types of samples, a higher concentration of alumina was found at the surface, whereas silica mostly constituted the core of the sample. A thermal treatment in a humid atmosphere was shown to redistribute the silica inside the sample as well as on its surface, which decreased the specific surface area at the same time. The acid sites localisation was defined as a specific curve at the interface between the two components upon reaching the surface of the support. The length of this curve, the “alumina–silica boundary line”, was estimated by using EFTEM tomography and discussed qualitatively with the chemical inter‐mixing information deduced from additional techniques such as FTIR and NMR spectroscopy.
Spin Catalysis over Conductive Solids: Enhancing the Rate of Model C−C Bond Cracking over Carbon Nanoparticles
Authors: Khavryuchenko Oleksiy V. , Peslherbe Gilles H. 
Published: September 2016

AbstractThe concept of catalysis over a spin‐conductive mediator is investigated with quantum‐chemical calculations. Specifically, homolytic C−C bond cleavage in ethane over small edge‐oxidized half‐metallic carbon clusters in the presence of a methyl radical was considered with the complete active space self‐consistent field method. The methyl radical (spin catalyst) and carbon cluster (mediator) are found to share a common electronic orbital containing the radical unpaired electron, allowing nascent radicals emerging from ethane dissociation to interact with the spin catalyst through the carbon electronic system. This could result in spin flip, affording formation of a triplet radical pair not prone to recombination and thus resulting in the acceleration of the reaction rate. This demonstrates that new pathways may open up in controlled catalytic processes by allowing normally spin‐forbidden reactions and not necessarily lowering activation barriers in the traditional sense of catalysis.
Reaction and Mechanistic Studies of Heterogeneous Hydroamination over Support‐Stabilized Gold Nanoparticles
Authors: Sengupta Manideepa , Bag Arijit , Das Subhasis , Shukla Astha , Konathala L. N. Sivakumar , Naidu C. A. , Bordoloi Ankur 
Published: September 2016

AbstractHighly stable gold nanoparticles (GNPs) around 5–6 nm have been prepared by in situ reduction of chloroauric acid on the surface of nitrogen‐rich mesoporous carbon (MCN) without adding any extra stabilizing agent. The synthesized materials have been efficiently utilized as a catalyst for the truly heterogeneous hydroamination of phenylacetylene with aniline. Large turnover numbers (42×106) were achieved by suitably adjusting the gold/support (w/w) ratio, time, temperature, and solvent, leading to 98 % selectivity towards the Markovnikov product. Density functional theory (DFT) studies have been performed to predict the mechanistic pathway of hydroamination with Au0 in GNP@MCN. To understand the structure–activity relationship, the catalyst was characterized by using different techniques such as X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen physisorption studies (BET), X‐ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FTIR) spectroscopy.
Enhanced Photoelectrochemical Performance of the BiVO4/Zn:BiVO4 Homojunction for Water Oxidation
Authors: Su Jinzhan , Liu Cong , Liu Dongyu , Li Mingtao , Zhou Jinglan 
Published: September 2016

AbstractBismuth vanadate is a promising semiconductor for photoelectrochemical (PEC) water oxidation under visible light. Yet its PEC performance is limited by its poor electron‐transfer mobility. In this study we modified the BiVO4 surface with Zn to address this problem. We used a ZnO coating and etching treatment to dope Zn atoms at the surface of BiVO4 by replacing the Bi atoms. The surface Zn doping treatment lowered the Fermi level of the outer part of BiVO4 (surface) and formed a BiVO4/Zn:BiVO4 homojunction with a type II band alignment with the inner part of BiVO4 (bulk). With this homojunction, the charge transfer process across the depletion region of the BiVO4 electrode was improved and the surface trapping of photogenerated electrons was avoided, which led to an enhanced PEC performance.
Combined Function of Brønsted and Lewis Acidity in the Zeolite‐Catalyzed Isomerization of Glucose to Fructose in Alcohols
Authors: Saravanamurugan Shunmugavel , Riisager Anders , Taarning Esben , Meier Sebastian 
Published: September 2016

AbstractGlucose conversion via fructose to useful chemicals and fuels has attracted considerable attention. Isomerization of glucose to fructose can proceed along several different reaction pathways involving different sugar intermediates and isomeric forms. Presently, the roles of the substrate isomeric forms and of the catalyst properties remain incompletely understood. By using NMR spectroscopy, we elucidate the interplay of the catalyst active sites in converting monosaccharide forms to products, byproducts, and intermediates in alcohols.
Enantiodivergent Synthesis of (+)‐ and (−)‐Pyrrolidine 197B: Synthesis of trans‐2,5‐Disubstituted Pyrrolidines by Intramolecular Hydroamination
Authors: Pérez Sixto J. , Purino Martín A. , Cruz Daniel A. , López‐Soria Juan M. , Carballo Rubén M. , Ramírez Miguel A. , Fernández Israel , Martín Víctor S. , Padrón Juan I. 
Published: September 2016

AbstractA highly efficient, diastereoselective, iron(III)‐catalyzed intramolecular hydroamination/cyclization reaction involving α‐substituted amino alkenes is described. Thus, enantiopure trans‐2,5‐disubstituted pyrrolidines and trans‐5‐substituted proline derivatives were synthesized by means of a combination of enantiopure starting materials, easily available from l‐α‐amino acids, with sustainable metal catalysts such as iron(III) salts. The scope of this methodology is highlighted in an enantiodivergent approach to the synthesis of both (+)‐ and (−)‐pyrrolidine 197B alkaloids from l‐glutamic acid. In addition, a computational study was carried out to gain insight into the complete diastereoselectivity of the transformation.
Thermal Stability of Oxidized Single‐Walled Carbon Nanotubes: Competitive Elimination and Decomposition Reaction Depending on the Degree of Functionalization
Authors: Maeda Yutaka , Sone Erika , Nishino Akane , Amagai Yuri , Wang Wei‐Wei , Yamada Michio , Suzuki Mitsuaki , Matsui Jun , Mitsuishi Masaya , Okazaki Toshiya , Nagase Shigeru 
Published: September 2016

AbstractThe thermal stability of oxidized single‐walled carbon nanotubes (SWNTs) with various degrees of oxidation was investigated. The oxidized SWNTs exhibited lower absorption and radial breathing mode (RBM) peaks and a higher intensity ratio of the D band to the G band (D/G) in their absorption and Raman spectra than those of the pristine SWNTs. After the thermal treatment, the D/G ratio of the oxidized SWNTs almost recovered its original intensity, regardless of the degree of oxidation. The absorption, photoluminescence (PL), and RBM peaks could not recover their original intensities when the oxidation degree was high. The results indicate that the elimination and decomposition reactions proceeded competitively depending on the degree of oxidation. In addition, a new PL peak was observed in the near‐infrared region, and the PL peak intensity increased with the subsequent thermal treatment. The theoretical calculations provided an insight into the possible pathways for the decomposition of oxidized SWNTs, showing that the O2 elimination and CO/CO2 evolution proceed competitively during thermal treatment.
Selective Co‐Encapsulation Inside an M6L4 Cage
Authors: Leenders Stefan H. A. M. , Becker René , Kumpulainen Tatu , de Bruin Bas , Sawada Tomohisa , Kato Taito , Fujita Makoto , Reek Joost N. H. 
Published: September 2016

AbstractThere is broad interest in molecular encapsulation as such systems can be utilized to stabilize guests, facilitate reactions inside a cavity, or give rise to energy‐transfer processes in a confined space. Detailed understanding of encapsulation events is required to facilitate functional molecular encapsulation. In this contribution, it is demonstrated that Ir and Rh‐Cp‐type metal complexes can be encapsulated inside a self‐assembled M6L4 metallocage only in the presence of an aromatic compound as a second guest. The individual guests are not encapsulated, suggesting that only the pair of guests can fill the void of the cage. Hence, selective co‐encapsulation is observed. This principle is demonstrated by co‐encapsulation of a variety of combinations of metal complexes and aromatic guests, leading to several ternary complexes. These experiments demonstrate that the efficiency of formation of the ternary complexes depends on the individual components. Moreover, selective exchange of the components is possible, leading to formation of the most favorable complex. Besides the obvious size effect, a charge‐transfer interaction may also contribute to this effect. Charge‐transfer bands are clearly observed by UV/Vis spectrophotometry. A change in the oxidation potential of the encapsulated electron donor also leads to a shift in the charge‐transfer energy bands. As expected, metal complexes with a higher oxidation potential give rise to a higher charge‐transfer energy and a larger hypsochromic shift in the UV/Vis spectrum. These subtle energy differences may potentially be used to control the binding and reactivity of the complexes bound in a confined space.
An investigation on heat transfer of granular materials in the novel flighted rotary drum
Authors: Li Muyuan , Ling Xiang , Peng Hao , Cao Zhengyu , Wang Yan 
Published: September 2016

AbstractIn this study, a model is carried out to investigate heat transfer within a granular system in the novel flighted rotary drum (FRD). The model using Eulerian continuum approach (ECA) is developed and then verified by comparing with experimental data published previously. The effects of flight configuration, number of flights, rotational speed, and fill level on heat transfer characteristics are discussed. The results show that increasing rotational speed can intensify heat transfer to a certain degree, but it is not significant. The average temperature of granular materials increases with the increase of the number of flights and the decrease of the fill level. More importantly, the average temperature is strongly dependent on flight configurations (including different length ratios and flight tip angles). There is an enhancement in heat transfer when the length ratio S1/S2 is 1 or the flight tip angle is higher.
Theranostic Polyaminocarboxylate–Cyanine–Transferrin Conjugate for Anticancer Therapy and Near‐Infrared Optical Imaging
Authors: Kang Chi Soo , Ren Siyuan , Sun Xiang , Chong Hyun‐Soon 
Published: September 2016

AbstractIron chelation therapy has been recognized as a promising antitumor therapeutic strategy. Herein we report a novel theranostic agent for targeted iron chelation therapy and near‐infrared (NIR) optical imaging of cancers. The theranostic agent was prepared by incorporation of a polyaminocarboxylate‐based cytotoxic chelating agent (N‐NE3TA; 7‐[2‐[(carboxymethyl)amino]ethyl]‐1,4,7‐triazacyclononane‐1,4‐diacetic acid) and a NIR fluorescent cyanine dye (Cy5.5) onto a tumor‐targeting transferrin (Tf). The N‐NE3TA–Tf conjugate (without Cy5.5) was characterized and evaluated for antiproliferative activity in HeLa, HT29, and PC3 cancer cells, which have elevated expression levels of the transferrin receptor (TfR). The N‐NE3TA–Tf conjugate displayed significant inhibitory activity against all three cancer cell lines. The NIR dye Cy5.5 was then incorporated into N‐NE3TA–Tf, and the resulting cytotoxic and fluorescent transferrin conjugate N‐NE3TA–Tf–Cy5.5 was shown by microscopy to enter TfR‐overexpressing cancer cells. This theranostic conjugate has potential application for dual use in targeted iron chelation cancer therapy and NIR fluorescence imaging.
Graphitic Carbon Nitride Film: An Emerging Star for Catalytic and Optoelectronic Applications
Authors: Bian Juncao , Huang Chao , Zhang Rui‐Qin 
Published: September 2016

AbstractGraphitic carbon nitride (g‐CN) is a unique organic semiconductor that has been widely applied as a visible‐light‐driven photocatalyst. However, these applications are primarily based on g‐CN powders. Applications of g‐CN in devices are hindered because of difficulties associated with the synthesis of high‐quality g‐CN films. This work reviews the latest advances in g‐CN films. The deposition methods are summarized and the structural, optical, and electronic properties of g‐CN films and their applications in catalysis, solar cells, and light‐emitting diodes are outlined. Moreover, the challenges remaining in this field are also discussed.
The role of Omega‐3 docosapentaenoic acid in pregnancy and early development
Authors: Li Juan , Yin Huaixia , Bibus Douglas M. , Byelashov Oleksandr A. 
Published: September 2016

Docosapentaenoic acid (DPA, 22:5n‐3) is normally present in small quantities in marine products. Metabolically, it can directly convert to docosahexaenoic acid (DHA, 22:6n‐3) and retro‐convert into eicosapentaenoic acid (EPA, 20:5n‐3), suggesting that it may serve as a reservoir for these fatty acids in human body. Among other biological functions, DPA serves a precursor to anti‐inflammatory and pro‐resolving mediators. Further, either consumption of DPA or its blood levels are associated with positive human health outcomes, and in vitro and in vivo models have confirmed and highlighted DPA's biological role in mammals. Because the role of DHA in prenatal and postnatal development is well known, most infant formulas are now supplemented with DHA. Although human breast milk contains significant levels of DHA, importantly, its levels of DPA are comparable. Despite this, the importance of DPA in infant and maternal health is less recognized. Our review highlights that DPA intake (often along with EPA and DHA) by lactating mothers is linked to better neural development and bone health of children. Additionally, blood levels of DPA in mothers are associated with fewer allergic diseases such as asthma, rhinitis, and eczema in children and mothers. The daily dietary intake of DPA in breast‐fed infants in various populations ranges from 5.1 to 44.6 mg/kg body weight, which would translate to 357–3122 mg/d for a 70‐kg adult. The reported health effects of DPA suggest it may be beneficial to increase the intake of DPA during prenatal and early postnatal life stages.Practical applications: This paper reviewed all research articles related with DPA health benefits in human development and summarized the potential function of DPA in human during pregnancy and early development. In vitro and in vivo studies both indicated that DPA has important biological role in mammals. The fact that DPA is high in human breast milk shows the potential biological function of DPA in infant development. The authors recommend infant formula manufacturers to consider adding DPA to infant food and encourage researchers to conduct human clinical studies to further prove the biological function of DPA in human development.LC Omega‐3 fatty acids play a critical role in human nutrition and health. DPA's role as a reservoir for DHA and EPA highlights the importance in human physiology. This study demonstrates the association between blood DPA levels and both infant and maternal health, and suggests the recommendation for DPA consumption during prenatal and early postnatal life stages.
Electrothermal Annealing of Catalytic Platinum Microwire Electrodes: Towards Membrane‐Free pH 7 Glucose Micro‐Fuel Cells
Authors: Weber James , Wain Andrew J. , Attard Gary A. , Marken Frank 
Published: September 2016

AbstractSurface activation and cleaning of platinum micro‐wires of 25 micron diameter has been achieved by a short one‐second electrothermal annealing treatment in air at 0.3 A (to orange glow). Voltammetric data suggest a decrease in the electrochemically active surface area with annealing time and a change in surface structure towards the Pt(100) crystalline face. The impact of electrothermal annealing on the electrocatalytic activity towards (i) oxygen reduction and (ii) glucose oxidation in pH 7 phosphate buffered aqueous solutions is investigated. In contrast to as‐received platinum, annealed platinum produces an electrocatalytic response towards glucose oxidation with increasing glucose concentration. A short one‐second anneal step is just as effective in enhancing catalysis as prolonged electrochemical cleaning in sulphuric acid. Finally, by combining a non‐annealed and an annealed microwire electrode, a very simple membrane‐free micro‐fuel cell system is devised operating in phosphate buffer at pH 7 with linearly increasing power output reaching 2.2 nW cm−2 for high glucose levels of 0.5 M.
Basin‐scale methods for predicting salmonid spawning habitat via grain size and riffle spacing, tested in a California coastal drainage
Authors: Pfeiffer Allison M. , Finnegan Noah J. 
Published: September 2016

AbstractBasin‐scale predictive geomorphic models for river characteristics, particularly grain size, can aid in salmonid habitat identification. However, these basin‐scale methods are largely untested with actual habitat usage data. Here, we develop and test an approach for predicting grain size distributions from high resolution LiDAR (Light Detection and Ranging)‐derived topographic data for a 77 km2 watershed along the central California Coast. This approach improves on previous efforts in that it predicts the full grain size distribution and incorporates an empirically calibrated shear stress partitioning factor. The predicted grain size distributions are used to calculate the fraction of the bed area movable by spawning fish. We then compare the ‘movable fraction’ with 7 years of observed spawning data. We find that predicted movable fraction explains the paucity of spawning in the upper reaches of the study drainage, but does not explain variation along the mainstem. In search of another morphologic characteristic that may help explain the variation within the mainstem, we measure riffle density, a proxy for physical habitat complexity. We find that field surveys of riffle density explain 64% of the variation in spawning in these mainstem reaches, suggesting that within reaches of appropriate sized gravel, spawning density is related to riffle density. Because riffle density varies systematically with channel width, predicting riffle spacing is straightforward with LiDAR data. Taken together, these findings demonstrate the efficacy of basin‐scale spawning habitat predictions made using high‐resolution digital elevation models. Copyright © 2016 John Wiley & Sons, Ltd.
How does anisotropy in bedrock river granitic outcrops influence pothole genesis and development?
Authors: Ortega‐Becerril Jose , Gomez‐Heras Miguel , Fort Rafael , Wohl Ellen 
Published: September 2016

AbstractPothole formation and development may be influenced by joint sets and other heterogeneities within bedrock, as well as by hydraulics. Previous research indicates that most potholes found in rivers of the mountainous Spanish Central System exhibit preferred orientations associated with dominant joints and correlate more strongly with variations in substrate resistance than with hydraulics. Weathering and erosion weaken rock surfaces, which leads to decreased mechanical resistance. We start from the hypothesis that different mechanisms of pothole formation may create around the pothole a distinctive signature in terms of ultrasound pulse velocity and surface hardness. We develop a conceptual model and test it using potholes for which we know the mechanism of formation, demonstrating that the spatial and statistical distributions of dynamical mechanical properties and surface hardness of a pothole may provide insight into its genesis. Copyright © 2016 John Wiley & Sons, Ltd.