bluuebunny/crossref_metadata_2025_split huggingface dataset:
100 Jahre Max‐Planck‐Institut für Kohlenforschung
Authors: Reetz Manfred T. 
Published: June 2014

AbstractDieser Essay beschreibt die institutionelle und wissenschaftliche Entwicklung des Max‐Planck‐Instituts für Kohlenforschung in Mülheim an der Ruhr, des Nachfolge‐Instituts des 1914 gegründeten Kaiser‐Wilhelm‐Instituts für Kohlenforschung. Die vier Hauptteile des Essays entsprechen den vier historischen Perioden, die mit den jeweiligen Direktoren zusammenhängen: 1) Franz Fischer; 2) Karl Ziegler; 3) Günther Wilke; 4) die von Manfred T. Reetz initiierte Umstrukturierung, in deren Folge ein Direktorium bestehend aus fünf gleichberechtigten Direktoren mit jeweils einer Abteilung etabliert wurde. Zusätzlich zu den rein historischen und politischen Entwicklungen werden auch Höhepunkte der Forschung aus den vier Perioden beschrieben.
Microfluidic Studies of Carbon Dioxide
Authors: Abolhasani Milad , Günther Axel , Kumacheva Eugenia 
Published: June 2014

AbstractCarbon dioxide (CO2) sequestration, storage and recycling will greatly benefit from comprehensive studies of physical and chemical gas–liquid processes involving CO2. Over the past five years, microfluidics emerged as a valuable tool in CO2‐related research, due to superior mass and heat transfer, reduced axial dispersion, well‐defined gas–liquid interfacial areas and the ability to vary reagent concentrations in a high‐throughput manner. This Minireview highlights recent progress in microfluidic studies of CO2‐related processes, including dissolution of CO2 in physical solvents, CO2 reactions, the utilization of CO2 in materials science, and the use of supercritical CO2 as a “green” solvent.
Magnesierung funktionalisierter Heterocyclen und Acrylate unter Verwendung von TMPMgCl⋅LiCl in kontinuierlichem Fluss
Authors: Petersen Trine P. , Becker Matthias R. , Knochel Paul 
Published: June 2014

AbstractEs wird eine Durchflussmethode für die Metallierung funktionalisierter Heterocyclen (Pyridine, Pyrimidine, Thiophene und Thiazole) und verschiedener Acrylate unter Verwendung der starken, nichtnukleophilen Base TMPMgCl⋅LiCl beschrieben. Die Flussbedingungen ermöglichen Magnesierungen unter zweckmäßigeren Bedingungen als die entsprechenden Kolbenreaktionen, die oft tiefe Temperaturen und lange Reaktionszeiten benötigen. Ferner sind die Durchflussreaktionen ohne weitere Optimierung skalierbar und erlauben Metallierungen, die nicht das gewünschte Produkt im Reaktionskolben ergeben, wie die Magnesierung empfindlicher Acrylderivate. Die Magnesiumspezies reagieren im Anschluss mit verschiedenen Elektrophilen, wodurch vielfältige Funktionalitäten eingeführt werden.
Total Synthesis of Marinomycin A Based on a Direct Dimerization Strategy
Authors: Nishimaru Tatsuya , Kondo Masashi , Takeshita Kimito , Takahashi Keisuke , Ishihara Jun , Hatakeyama Susumi 
Published: June 2014

AbstractThe asymmetric total synthesis of (+)‐marinomycin A, a 44‐membered macrodiolide antitumor agent and antibiotic isolated from a marine actinomycete, Marinispora strain CNQ‐140, is reported. The key features of the synthesis include the highly convergent stereocontrolled construction of the monomeric hydroxy salicylate starting from asymmetric epoxidation of the σ‐symmetrical dialkenyl carbinol, and an unprecedented direct dimerization through NaHMDS‐promoted double transesterification.
General Synthesis of Multi‐Shelled Mixed Metal Oxide Hollow Spheres with Superior Lithium Storage Properties
Authors: Zhang Genqiang , Lou Xiong Wen (David) 
Published: June 2014

AbstractComplex hollow structures of transition metal oxides, especially mixed metal oxides, could be promising for different applications such as lithium ion batteries. However, it remains a great challenge to fabricate well‐defined hollow spheres with multiple shells for mixed transition metal oxides. Herein, we have developed a new “penetration–solidification–annealing” strategy which can realize the synthesis of various mixed metal oxide multi‐shelled hollow spheres. Importantly, it is found that multi‐shelled hollow spheres possess impressive lithium storage properties with both high specific capacity and excellent cycling stability. Specifically, the carbon‐coated CoMn2O4 triple‐shelled hollow spheres exhibit a specific capacity of 726.7 mA h g−1 and a nearly 100 % capacity retention after 200 cycles. The present general strategy could represent a milestone in design and synthesis of mixed metal oxide complex hollow spheres and their promising uses in different areas.
Synthesis of (Carbo)nucleoside Analogues by [3+2] Annulation of Aminocyclopropanes
Authors: Racine Sophie , de Nanteuil Florian , Serrano Eloisa , Waser Jérôme 
Published: June 2014

Abstract(Carbo)nucleoside derivatives constitute an important class of pharmaceuticals, yet there are only few convergent methods to access new analogues. Here, we report the first synthesis of thymine‐, uracil‐, and 5‐fluorouracil‐substituted diester donor–acceptor cyclopropanes and their use in the indium‐ and tin‐catalyzed [3+2] annulations with aldehydes, ketones, and enol ethers. The obtained diester products could be easily decarboxylated and reduced to the corresponding alcohols. The method gives access to a broad range of new (carbo)nucleoside analogues in only four or five steps and will be highly useful for the synthesis of libraries of bioactive compounds.
An Ultrastable Anode for Long‐Life Room‐Temperature Sodium‐Ion Batteries
Authors: Yu Haijun , Ren Yang , Xiao Dongdong , Guo Shaohua , Zhu Yanbei , Qian Yumin , Gu Lin , Zhou Haoshen 
Published: June 2014

AbstractSodium‐ion batteries are important alternative energy storage devices that have recently come again into focus for the development of large‐scale energy storage devices because sodium is an abundant and low‐cost material. However, the development of electrode materials with long‐term stability has remained a great challenge. A novel negative‐electrode material, a P2‐type layered oxide with the chemical composition Na2/3Co1/3Ti2/3O2, exhibits outstanding cycle stability (ca. 84.84 % capacity retention for 3000 cycles, very small decrease in the volume (0.046 %) after 500 cycles), good rate capability (ca. 41 % capacity retention at a discharge/charge rate of 10 C), and a usable reversible capacity of about 90 mAh g−1 with a safe average storage voltage of approximately 0.7 V in the sodium half‐cell. This P2‐type layered oxide is a promising anode material for sodium‐ion batteries with a long cycle life and should greatly promote the development of room‐temperature sodium‐ion batteries.
(Aminocarbene)(Divinyltetramethyldisiloxane)Iron(0) Compounds: A Class of Low‐Coordinate Iron(0) Reagents
Authors: Zhang Hezhong , Ouyang Zhenwu , Liu Yuesheng , Zhang Qiang , Wang Lei , Deng Liang 
Published: June 2014

AbstractThe combined use of aminocarbene and divinyltetramethyldisiloxane (dvtms) as supporting ligands enables the access of unprecedented low‐coordinate iron(0) alkene compounds [LnFe(η2:η2‐dvtms)] (L=N‐heterocyclic carbene (NHC) or cyclic (alkyl)(amino)carbene (CAAC), n=1 or 2) from the reactions of FeCl2 with alkali‐metal reducing agents, free aminocarbene ligands, and dvtms. The iron(0) species deliver their {LnFe0} fragments to perform redox reactions with Ph2SiH2, S8, Se, and DippN3, furnishing novel aminocarbene‐supported iron(IV) silylene, all‐ferrous iron–sulfur/selenium cubanes, and bis(imido)iron(IV) compounds. These conversions demonstrate the potential synthetic utility of the carbene‐supported iron(0) complexes as a valuable class of low‐coordinate iron(0) reagents.
Polyvinyl chloride composites filled with olive stone flour: Mechanical, thermal, and water absorption properties
Authors: Naghmouchi Ilhem , Mutjé Pere , Boufi Sami 
Published: June 2014

ABSTRACTThe production of olive oil leads to considerable amounts of solid waste mainly composed of hard woody endocarp called olive stones. The aim of this work is to explore the possible use of ground olive stones as fillers for polyvinyl chloride (PVC), to elaborate a cost‐effective composite material with a solid loading of up to 50 wt %. After grinding, the ensuing olive stone flour (OSF) was incorporated into a PVC matrix via melt compounding and injection molding to elaborate PVC‐OSF‐based composites with a filler content up to 50 wt %. The evolution of the mechanical performance, the impact property, the water absorbance, and wear resistance behavior, according to the OSF content, were investigated. The addition of OSF was shown to enhance the stiffness of the matrix, but at the expense of its mechanical strength. However, the strength of the composite did not fall as low as 30 MPa, and therefore, meets the requirements for many applications in plastic‐based materials. The thermal properties of the ensuing composites were also studied by thermogravimetric analysis. The results show that the addition of OSF may be effective in increasing the stiffness of the PVC‐based composite and in reducing the solid residue in the olive oil industry production. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41083.
Hg(II) removal from HCl solutions using a tetraalkylphosphonium ionic liquid impregnated onto Amberlite XAD‐7
Authors: Navarro Ricardo , Alba Janette , Saucedo Imelda , Guibal Eric 
Published: June 2014

ABSTRACTExtractant impregnated resins (EIRs) were prepared by impregnation of Amberlite XAD‐7 with tetraalkylphosphonium chloride ionic liquid (IL). The EIRs were tested for the sorption of Hg(II) in HCl solutions. Mercury is bound on the EIR through an ion exchange mechanism involving chloroanionic species and the IL. The effect of HCl concentration and IL content is studied and the sorption isotherms are obtained in 1 M HCl solutions: the sorption capacity linearly increases with IL loading up to 100 mg Hg L−1. A little fraction of the IL immobilized on the resin (about 40 mg IL g−1) is tightly bound to the polymer limiting its reactivity with metal ions. The uptake kinetics are mainly controlled by intraparticle diffusion. At high IL loading the kinetics are slowed down, while the temperature has a limited impact. Nitric acid can be used for desorbing mercury and recycling the EIR for at least five cycles. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41086.
Antimicrobial cytocompatible pentaerythritol triacrylate‐co‐trimethylolpropane composite scaffolds for orthopaedic implants
Authors: Smoak Mollie , Chen Cong , Qureshi Ammar , Garber Leah , Pojman John A. , Janes Marlene E. , Hayes Daniel J. 
Published: June 2014

ABSTRACTAs of 2010, 5.3 million orthopedic surgeries are performed each year, and this number is expected to increase to 6.2 million by 2020. On average, 27.7% of all orthopedic surgeries result in infection which often leads to osteomyelitis and the loss of supporting bone. In this study, we describe two synthetic bone grafts, or augmentation methods, for a biodegradable, silver nanoparticle (SNPs) containing antimicrobial scaffolds composed of pentaerythritol triacrylate‐co‐trimethylolpropane tris (3‐mercaptopropionate) (PETA) and hydroxyapatite (HA). This osteoinductive and degradable material is designed to stimulate proliferation of bone progenitor cells, and provide controlled release of antimicrobial components. The first method, denoted as the “incorporating method,” involves dissolving SNPs in ethanol, butanol, or isopropanol and directly incorporating the particles into the scaffold prior to polymerization. The second method, “coating method,” involves submerging fabricated scaffolds into their respective SNPs‐solution and mixing for 24 h. The coating method allowed better distribution and release of SNPs from the surface of the composites when exposed to extracellular media. The in vitro release of silver for both methods was quantified by inductively coupled plasma optical emission spectroscopy (ICP‐OES). The scaffolds made by means of the coating method showed increased release of silver with respect to time; no silver leached from the scaffolds formed by the incorporating method. Use of Alamar Blue assay demonstrated that the SNPs incorporation did not affect cell viability when tested with hASCs. The scaffolds formed by the coating method inhibited the proliferation of Staphylococcus aureus 99.5% and Escherichia coli by 99.9% within 24 h. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41099.
Thermal stability of modified end‐capped poly(lactic acid)
Authors: Berger Katrin , Gregorova Adriana 
Published: June 2014

ABSTRACTThe influence of functional end groups on the thermal stability of poly(lactic acid) (PLA) in nitrogen‐ and oxygen‐enriched atmospheres has been investigated in this article using differential scanning calorimetry, thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA). Functional end groups of PLA were modified by succinic anhydride and l‐cysteine by the addition–elimination reaction. PLA was synthesized by azeotropic condensation of l‐lactic acid in xylene and characterized by nuclear magnetic resonance. The values of the activation energies determined by TGA in nitrogen and oxygen atmospheres revealed that the character of functional end groups has remarkable influence on the thermal stability of PLA. Moreover, DMA confirmed the strong influence of functional end groups of PLA on polymer chains motion. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 41105.
Remarkable Shape‐Sustaining, Load‐Bearing, and Self‐Healing Properties Displayed by a Supramolecular Gel Derived from a Bis‐pyridyl‐bis‐amide of L‐Phenyl Alanine
Authors: Das Uttam Kumar , Banerjee Subhabrata , Dastidar Parthasarathi 
Published: June 2014

AbstractA series of bis‐amides decorated with pyridyl and phenyl moieties derived from L‐amino acids having an innocent side chain (L‐alanine and L‐phenyl alanine) were synthesized as potential low‐molecular‐weight gelators (LMWGs). Both protic and aprotic solvents were found to be gelled by most of the bis‐amides with moderate to excellent gelation efficiency (minimum gelator concentration=0.32–4.0 wt. % and gel–sol dissociation temperature Tgel=52–110 °C). The gels were characterized by rheology, DSC, SEM, TEM, and temperature‐variable 1H NMR measurements. pH‐dependent gelation studies revealed that the pyridyl moieties took part in gelation. Structure–property correlation was attempted using single‐crystal X‐ray and powder X‐ray diffraction data. Remarkably, one of the bis‐pyridyl bis‐amide gelators, namely 3,3‐Phe (3‐pyridyl bis‐amide of L‐phenylalanine) displayed outstanding shape‐sustaining, load‐bearing, and self‐healing properties.
Superior Supercapacitor Properties of Composite Powders with Amorphous NiO Nanoclusters Distributed Uniformly in an Amorphous Carbon Matrix
Authors: Choi Seung Ho , Kang Yun Chan , Choi Yun Ju , Kim Yang Soo 
Published: June 2014

AbstractAmorphous nickel oxide–carbon composite powders have been prepared using a facile spray‐drying process. The nickel nitrate–citrate hydrate precursor powders were transformed into an amorphous NiO–carbon composite powder through a post‐treatment at 250 °C for 1 h. The excellent supercapacitor performance of the amorphous NiO–carbon composite powder can be ascribed to the unique electrochemical behavior of the ultrafine amorphous NiO nanoclusters.
Sumanenemonoone Imines Bridged by Redox‐Active π‐Conjugated Unit: Synthesis, Stepwise Coordination to Palladium(II), and Laser‐Induced Formation of Nitrogen‐Doped Graphitic Carbon
Authors: Amaya Toru , Inada Yuhi , Shimizu Yasutomo , Saeki Akinori , Tsuji Ryotaro , Seki Shu , Hirao Toshikazu 
Published: June 2014

AbstractSumanenemonoone imine compounds bridged by a redox‐active π‐conjugated unit on the basis of the conversion between 1,4‐phenylenediamine and 1,4‐benzoquinonediimine were synthesized and characterized. The stepwise coordination of the imino groups to PdII in the sumanenemonoone imine compound bridged by 1,4‐benzoquinonediimine was indicated by the titration experiment. Laser irradiation of a film of the metal‐free quionediimine gave nitrogen‐doped graphitic carbon, which was supported by an increase in conductivity and by Raman spectroscopy. The obtained graphitic carbon corresponds to carbonous compounds thermally treated at approximately 700–1000 °C. The ratio of nitrogen and carbon relative to that in the starting compound was nearly completely retained (5.4 % decrease).
Patient-reported outcomes 5–8 years after ultrasound-guided foam sclerotherapy for varicose veins
Authors: Darvall K A L , Bate G R , Bradbury A W 
Published: June 2014

Abstract

Background
The aim was to determine the long-term (5–8 years) outcomes of ultrasound-guided foam sclerotherapy (UGFS) for varicose veins using health-related quality of life (HRQL), patient-reported outcomes (PROMs), patient satisfaction and retreatment rates.

Methods
Consecutive patients undergoing UGFS between April 2004 and May 2007 were invited for review at least 5 years after treatment. Patients completed generic (Short Form 12) and disease-specific (Aberdeen Varicose Vein Symptom Severity Score, AVSS) HRQL instruments, and questionnaires enquiring about lower limb symptoms, lifestyle factors and satisfaction with treatment. Data on retreatments were recorded prospectively.

Results
A total of 391 limbs in 285 patients were included (81·2 per cent response rate) at a median of 71 (i.q.r. 67–78) months following first UGFS treatment. Originally 72·1 per cent had symptomatic, uncomplicated varicose veins, 21·9 per cent had undergone surgery previously, 87·2 per cent had treatment of great saphenous veins and 19·9 per cent treatment of short saphenous veins. Disease-specific HRQL scores improved significantly at long-term follow-up, with 88·5 per cent having an improved AVSS compared with baseline. Regarding lower limb symptoms and lifestyle improvement, 62·7–93·8 per cent of patients had their pretreatment expectations met or exceeded. Overall, 82·0 per cent were very satisfied with their treatment and only 3·3 per cent were dissatisfied; 91·0 per cent would recommend the treatment to others. Some 15·3 per cent of limbs required retreatment by 5 years (Kaplan–Meier analysis).

Conclusion
UGFS has durable results as reported by PROMs to at least 5 years. Only 15·3 per cent of limbs required retreatment for recurrence during follow-up.
Chemoenzymatic Synthesis of Bifunctional Polyubiquitin Substrates for Monitoring Ubiquitin Chain Remodeling
Authors: Trang Vivian H. , Rodgers Margaret L. , Boyle Kevin J. , Hoskins Aaron A. , Strieter Eric R. 
Published: June 2014

AbstractCovalent attachment of ubiquitin to target proteins is one of the most pervasive post‐translational modifications in eukaryotes. Target proteins are often modified with polymeric ubiquitin chains of defined lengths and linkages that may further undergo dynamic changes in composition in response to cellular signals. Biochemical characterization of the enzymes responsible for building and destroying ubiquitin chains is often thwarted by the lack of methods for preparation of the appropriate substrates containing probes for biochemical or biophysical studies. We have discovered that a yeast ubiquitin C‐terminal hydrolase (Yuh1) also catalyzes transamidation reactions that can be exploited to prepare site‐specifically modified polyubiquitin chains produced by thiol‐ene chemistry. We have used this chemoenzymatic approach to prepare dual‐functionalized ubiquitin chains containing fluorophore and biotin modifications. These dual‐functionalized ubiquitin chains enabled the first real‐time assay of ubiquitin chain disassembly by a human deubiquitinase (DUB) enzyme by single molecule fluorescence microscopy. In summary, this work provides a powerful new tool for elucidating the mechanisms of DUBs and other ubiquitin processing enzymes.
Modulation of Amyloid‐β Aggregation by Histidine‐Coordinating Cobalt(III) Schiff Base Complexes
Authors: Heffern Marie C. , Velasco Pauline T. , Matosziuk Lauren M. , Coomes Joseph L. , Karras Constantine , Ratner Mark A. , Klein William L. , Eckermann Amanda L. , Meade Thomas J. 
Published: June 2014

AbstractOligomers of the Aβ42 peptide are significant neurotoxins linked to Alzheimer's disease (AD). Histidine (His) residues present at the N terminus of Aβ42 are believed to influence toxicity by either serving as metal–ion binding sites (which promote oligomerization and oxidative damage) or facilitating synaptic binding. Transition metal complexes that bind to these residues and modulate Aβ toxicity have emerged as therapeutic candidates. Cobalt(III) Schiff base complexes (Co–sb) were evaluated for their ability to interact with Aβ peptides. HPLC‐MS, NMR, fluorescence, and DFT studies demonstrated that Co–sb complexes could interact with the His residues in a truncated Aβ16 peptide representing the Aβ42 N terminus. Coordination of Co–sb complexes altered the structure of Aβ42 peptides and promoted the formation of large soluble oligomers. Interestingly, this structural perturbation of Aβ correlated to reduced synaptic binding to hippocampal neurons. These results demonstrate the promise of Co–sb complexes in anti‐AD therapeutic approaches.
Pure and Alloyed Copper‐Based Nanoparticles Supported on Activated Carbon: Synthesis and Electrocatalytic Application in the Reduction of Nitrobenzene
Authors: Sheng Xia , Wouters Benny , Breugelmans Tom , Hubin Annick , Vankelecom Ivo F. J. , Pescarmona Paolo P. 
Published: June 2014

AbstractA series of Cu–CuxO, Pt–Cu alloy, and Pt nanoparticles supported on inexpensive activated carbon with large surface area were developed as electrocatalysts for the reduction of nitrobenzene. This reaction can produce useful chemicals with the potential to cogenerate electricity if applied in a fuel cell. Both the nature of the metal employed and of the carbon material used as support play an important role in determining the performance of the electrocatalysts. Cu‐based materials display lower onset potentials for the reduction of nitrobenzene, whereas the features of the activated carbon influence the stability of the electrocatalysts. The most promising electrocatalyst consisted of highly dispersed and very small Cu–CuxO nanoparticles (∼4 nm) supported on Norit activated carbon, which were prepared using H2 as reductant. A chronoamperometric test in acidic ethanolic medium gave good conversion of nitrobenzene over this electrocatalyst, with azoxybenzene as the major product.
Synthesis of Hybrid Electroactive Materials by Low‐Potential Electropolymerization of Gold Nanoparticles Capped with Tailored EDOT‐Thiophene Precursor Units
Authors: Yassin Ali , Oçafrain Maiténa , Blanchard Philippe , Mallet Romain , Roncali Jean 
Published: June 2014

AbstractThe synthesis of gold nanoparticles (GNPs) capped with alkanethiols with terminal bithiophenic polymerizable groups, consisting of 3,4‐ethylenedioxythiophene (EDOT) and 3‐alkylsulfanylthiophene, is described. Transmission electron microscopy (TEM) and light diffusion show that these stabilized GNPs have an average size of 2–3 nm with low polydispersity. The electrochemical behavior of C10S‐Au is investigated in dichloromethane in the presence of Bu4NPF6. The results show that these capped GNPs undergo straightforward and efficient electropolymerization under potentiodynamic or potentiostatic conditions. TEM images show that the electrodeposited films of the composite material present a very homogeneous structure, in which the size of the GNPs incorporated into the polythiophene matrix is unchanged. Results of cyclic voltammetry and spectroelectrochemistry obtained on polymer films deposited on platinum electrodes and transparent indium tin oxide electrodes, respectively, show that the reversible charging–discharging process and electrochromic behavior typical of poly(thiophenes) are preserved in the hybrid electroactive material.