bluuebunny/crossref_metadata_2025 huggingface dataset:
Catechols as Sources of Hydrogen Atoms in Radical Deiodination and Related Reactions
Authors: Povie Guillaume , Ford Leigh , Pozzi Davide , Soulard Valentin , Villa Giorgio , Renaud Philippe
Published: July 2016

When used with trialkylboranes, catechol derivatives, which are low‐cost and low toxicity, are valuable hydrogen atom donors for radical chain reactions involving alkyl iodides and related radical precursors. The system 4‐tert‐butylcatechol/triethylborane has been used to reduce a series of secondary and tertiary iodides, a xanthate, and a thiohydroxamate ester. Catechol derivatives are right in the optimal kinetic window for synthetic applications, as demonstrated by highly efficient radical cyclizations. Cyclizations leading to the formation of quaternary centers can be performed in an all‐at‐once process (no slow addition of the hydrogen atom donor) at standard concentrations. The H‐donor properties of catechol derivatives can be fine‐tuned by changing their substitution pattern. In slow radical cyclization processes, an enhanced ratio of cyclized/uncyclized products was obtained by using 3‐methoxycatechol instead of 4‐tert‐butylcatechol.
Access to Pyrazolidin‐3,5‐diones through Anodic N–N Bond Formation
Authors: Gieshoff Tile , Schollmeyer Dieter , Waldvogel Siegfried R.
Published: July 2016

Pyrazolidin‐3,5‐diones are important motifs in heterocyclic chemistry and are of high interest for pharmaceutical applications. In classic organic synthesis, the hydrazinic moiety is installed through condensation using the corresponding hydrazine building blocks. However, most N,N′‐diaryl hydrazines are toxic and require upstream preparation owing to their low commercial availability. We present an alternative and sustainable synthetic approach to pyrazolidin‐3,5‐diones that employs readily accessible dianilides as precursors, which are anodically converted to furnish the N−N bond. The electroconversion is conducted in a simple undivided cell under constant‐current conditions.
Epoxy modification with poly(vinyl acetate) and poly(vinyl butyral). I. Structure, thermal, and mechanical characteristics
Authors: Brantseva T. V. , Solodilov V. I. , Antonov S. V. , Gorbunova I. Y. , Korohin R. A. , Shapagin A. V. , Smirnova N. M.
Published: July 2016

Efficiency of the application of high strength heat resistant thermoplastics for improving fracture toughness and impact properties of epoxy resins motivated authors to try large‐scale production thermoplastics for the same purpose. Epoxy/anhydride systems were modified by up to 8 wt % poly(vinyl acetate) (PVAc) and up to 6 wt % poly(vinyl butyral) (PVB). In epoxy–PVAc blends it was possible to obtain morphologies with continuous thermoplastic phase. However, only sea‐island morphologies with a very small size of PVB‐rich phase were observed in epoxy–PVB matrices. The former type of morphology allowed a notable 2.4‐fold increase in the fracture toughness of epoxy resin and simultaneous up to 30% decrease in its' impact strength. The latter type of morphology caused a notably lower (45%) enhancement of the epoxy fracture toughness combined with a 50% increase in its' impact strength. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44081.
Preparation of polypropylene/octadecane composite films and their use in the packaging of cherry tomatoes
Authors: Kim Dowan , Lim Mijin , Seo Jongchul
Published: July 2016

Polypropylene (PP)/octadecane (OD) composite films were prepared via twin‐screw extrusion, and their chemical, morphological, thermal, and surface properties and oxygen and water vapor permeabilities were analyzed as functions of the OD content and temperature. OD was dispersed well in the PP matrix, and two phases (i.e., the PP and OD portions) were present in the PP/OD composite films. When the temperature was increased from 10 to 30 °C, both the oxygen transmittance rate and the water vapor transmittance rate of the PP/OD composite films increased sharply because of the influence of the OD content. These results were related to the temperature‐dependent changes in the morphological structure, such as changes in the the tortuous paths and crystallinity in the composite films because of the addition of OD. In the storage test, the PP/OD (83:17) composite films continuously controlled the gas concentration of the headspace and protected against environmental factors; this reduced the enzymatic activity and led to higher quality cherry tomatoes compared to the case when the pure PP and MP33000 films were used. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 44087.
Highly Efficient Photocatalysts and Continuous‐Flow Photocatalytic Reactors for Degradation of Organic Pollutants in Wastewater
Authors: Chang Sujie , Yang Xiaoqiu , Sang Yuanhua , Liu Hong
Published: July 2016

One of the most important applications for photocatalysis is engineered water treatment that photodegrades organic pollutants in wastewater at low cost. To overcome the low efficiency of batch degradation methods, continuous‐flow photocatalytic reactors have been proposed and have become the most promising method for mass water treatment. However, most commercial semiconductor photocatalysts are granular nanoparticles with low activity and a narrow active light wavelength band; this creates difficulties for direct use in continuous‐flow photocatalytic reactors. Therefore, a high‐performance photodegradation photocatalyst with proper morphology or structure is key for continuous photocatalytic degradation. Moreover, a well‐designed photocatalytic device is another important component for continuous‐flow photocatalysis and determines the efficiency of photocatalysis in practical water treatment. This review describes the basic design principles and synthesis of photocatalysts with excellent performance and special morphologies suitable for a filtering photocatalysis process. Certain promising continuous photodegradation reactors are also categorized and summarized. Additionally, selected scientific and technical problems that must be urgently solved are suggested.
Benzoic‐Imine‐Based Physiological‐pH‐Responsive Materials for Biomedical Applications
Authors: Qu Xiaozhong , Yang Zhenzhong
Published: July 2016

The benzoic imine is a dynamic covalent bond, which is stable around neutral pH value (ca. 7.4), but starts to hydrolyze at the extracellular pH value of solid tumors (ca. 6.5) and rapidly disintegrates at endosome and lysosome pH values (ca. 4.5–6.5). This characteristic is promising for the construction of physiological‐pH‐responsive materials, such as polymeric micelles, nanoparticles, and hydrogels for pharmaceutical and tissue‐engineering applications. This Focus Review summarizes recent progress in the design and synthesis of pH‐sensitive materials that contain the benzoic imine bond with biomedical objectives.
Highly Efficient, Reproducible, Uniform (CH3NH3)PbI3 Layer by Processing Additive Dripping for Solution‐Processed Planar Heterojunction Perovskite Solar Cells
Authors: Kim Hansol , Jeong Hanbin , Lee Jae Kwan
Published: July 2016

A processing additive dripping (PAD) approach to forming highly efficient (CH3NH3)PbI3 (MAPbI3) perovskite layers was investigated. A MAPbI3(CB/DIO) perovskite film fabricated by this approach, which included briefly dripping chlorobenzene incorporating a small amount of diiodooctane (DIO) during casting of a MAPbI3 perovskite precursor dissolved in dimethylformamide, exhibited superior smooth, uniform morphologies with high crystallinity and large grains and revealed completely homogeneous surface coverage. The surface coverage and morphology of the substrate significantly affected the photovoltaic performance of planar heterojunction (PHJ) perovskite solar cells (PrSCs), resulting in a power conversion efficiency of 11.45 % with high open‐circuit voltage of 0.91 V and the highest fill factor of 80.87 %. Moreover, the PAD approach could effectively provide efficient MAPbI3(CB/DIO) perovskite layers for highly efficient, reproducible, uniform PHJ PrSC devices without performance loss or variation even over larger active areas.
Rhodium(III)‐Catalyzed Tandem [2+2+2] Annulation–Lactamization of Anilides with Two Alkynoates via Cleavage of Two Adjacent C−H or C−H/C−O bonds
Authors: Fukui Miho , Shibata Yu , Hoshino Yuki , Sugiyama Haruki , Teraoka Kota , Uekusa Hidehiro , Noguchi Keiichi , Tanaka Ken
Published: July 2016

An electron‐deficient CpE rhodium(III) complex bearing a cyclopentadienyl ligand with two ethyl ester substituents catalyzes the tandem [2+2+2] annulation–lactamization of acetanilides with two alkynoates via cleavage of adjacent two C−H bonds to give densely substituted benzo[cd]indolones. The reactions of meta‐methoxy‐substituted acetanilides with two alkynoates also provided benzo[cd]indolones via cleavage of adjacent C−H/C−O bonds. Furthermore, 3,5‐dimethoxyacetanilides reacted with two alkynoates to give dearomatized spiro compounds.
Evaluating the toxicity of bDtBPP on CHO‐K1 cells for testing of single‐use bioprocessing systems considering media selection, cell culture volume, mixing, and exposure duration
Authors: Shah Rhythm R. , Linville Taylor W. , Whynot Andrew D. , Brazel Christopher S.
Published: July 2016

Single‐use bioprocessing bags are gaining popularity due to ease of use, lower risk of contamination, and ease of process scale‐up. Bis(2,4‐di‐tert‐butylphenyl)phosphate (bDtBPP), a degradant of tris(2,4‐di‐tert‐butylphenyl)phosphite, marketed as Irgafos 168®, which is an antioxidant stabilizer added to resins, has been identified as a potentially toxic leachate which may impact the performance of single‐use, multilayer bioprocessing bags. In this study, the toxicity of bDtBPP was tested on CHO‐K1 cells grown as adherent or suspended cells. The EC50 (effective concentration to cause 50% cell death) for adherent cells was found to be one order of magnitude higher than that for suspended CHO‐K1 cells. While CHO‐K1 cells had good cell viability when exposed to moderate concentrations of bDtBPP, the degradant was shown to impact the viable cell density (VCD) at much lower concentrations. Hence, in developing an industry‐standard assay for testing the cytotoxicity of leachates, suspended cells (as commonly used in the bioprocessing industry) would likely be most sensitive, particularly when reporting EC50 values based on VCD. The effects of mixing, cell culture volume, and exposure duration were also evaluated for suspended CHO‐K1 cells. It was found that the sensitivity of cell culture to leachates from single‐use plastic bags was enhanced for suspended cells cultured for longer exposure times and when the cells were subjected to continuous agitation, both of which are important considerations in the production of biopharmaceuticals. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1318–1323, 2016
Techno‐economic analysis for incorporating a liquid–liquid extraction system to remove acetic acid into a proposed commercial scale biorefinery
Authors: Aghazadeh Mahdieh , Engelberth Abigail S.
Published: July 2016

Mitigating the effect of fermentation inhibitors in bioethanol plants can have a great positive impact on the economy of this industry. Liquid–liquid extraction (LLE) using ethyl acetate is able to remove fermentation inhibitors—chiefly, acetic acid—from an aqueous solution used to produce bioethanol. The fermentation broth resulting from LLE has higher performance for ethanol yield and its production rate. Previous techno‐economic analyses focused on second‐generation biofuel production did not address the impact of removing the fermentation inhibitors on the economic performance of the biorefinery. A comprehensive analysis of applying a separation system to mitigate the fermentation inhibition effect and to provide an analysis on the economic impact of removal of acetic acid from corn stover hydrolysate on the overall revenue of the biorefinery is necessary. This study examines the pros and cons associated with implementing LLE column along with the solvent recovery system into a commercial scale bioethanol plant. Using details from the NREL‐developed model of corn stover biorefinery, the capital costs associated with the equipment and the operating cost for the use of solvent were estimated and the results were compared with the profit gain due to higher ethanol production. Results indicate that the additional capital will add 1% to the total capital and manufacturing cost will increase by 5.9%. The benefit arises from the higher ethanol production rate and yield as a consequence of inhibitor extraction and results in a $0.35 per gallon reduction in the minimum ethanol selling price (MESP). © 2016 American Institute of Chemical EngineersBiotechnol. Prog., 32:971–977, 2016
Was coach's dismissal based on his national origin?
Authors: Gelpi Aileen
Published: July 2016

Oleg Soloviev — born in Russia — became the aquatics director and head coach of the men's swim team at the College of Staten Island, City University of New York, in 1995.
Bioresorbable vascular scaffold use for coronary bifurcation lesions: A substudy from GHOST EU registry
Authors: Naganuma Toru , Colombo Antonio , Lesiak Maciej , Capodanno Davide , Gori Tommaso , Nef Holger , Caramanno Giuseppe , Naber Christoph , Di Mario Carlo , Ruparelia Neil , Capranzano Piera , Wiebe Jens , Araszkiewicz Aleksander , Geraci Salvatore , Kawamoto Hiroyoshi , Pyxaras Stelios , Mattesini Alessio , Münzel Thomas , Tamburino Corrado , Latib Azeem
Published: July 2016

Objectives

The aim of this study was to evaluate midterm outcomes of bioresorbable vascular scaffolds (BVS) implanted in bifurcation lesions.

Background

BVS have emerged as an alternative to conventional metallic drug‐eluting stents for the treatment of coronary complex lesions.

Methods

Between November 2011 and January 2014, 1189 patients underwent percutaneous coronary intervention with BVS at 10 European centers (GHOST EU registry). Of these, 289 consecutive patients (302 bifurcation lesions) treated with either single‐stenting (n = 260) or double‐stenting (n = 42) were evaluated.

Results

True bifurcations were treated in 44.7%. Intravascular ultrasound and optical coherence tomography were utilized only in 22.2% and 21.2%, respectively. Predilation was performed in 95.4%, while postdilation of the main branch was performed in 61.3%. Final kissing inflation with no or minimal protrusion of a side‐branch balloon into main branch was performed in 18.9%. Median follow‐up period was 356 (IQR 191–419) days. The Kaplan–Meier estimated rates of target lesion failure and scaffold thrombosis (ST) were 6.4% and 2.5% at 360 days, respectively. Independent predictors for TLF were ACS and diabetes mellitus (HR 4.67; 95% CI: 1.78–12.3; P = 0.002 and HR 3.37; 95% CI: 1.38–8.26; P = 0.008, respectively).

Conclusions

BVS use for coronary bifurcation lesions in an “all‐comer” population was associated with acceptable TLF rates up to midterm follow‐up. However, ST rates were higher than seen with contemporary metallic stents possibly due to the low incidence of intravascular guidance and postdilation resulting in a higher likelihood of scaffold underexpansion and malapposition, further supporting the importance of meticulous implantation technique. © 2016 Wiley Periodicals, Inc.
Tetrachloromethane as an Effective Agent to Transform Nanoparticles of Palladium and Gold in Supported Catalysts
Authors: Bonarowska Magdalena , Kaszkur Zbigniew , Słowik Grzegorz , Ryczkowski Janusz , Karpiński Zbigniew
Published: July 2016

The use of CCl4 as an effective medium to generate important phase changes in supported Pd and Au catalysts is presented. The dissolution of carbon that originates from CCl4 to form a PdC0.13 solid solution is more complete for the lowest temperature of the CCl4+H2 reaction (30–50 °C). At higher temperatures, the bulk carbiding competes with the hydrogenative removal of bare carbon species to contribute to an enhanced CH4 and C2H6 formation.
Alternate to Molybdenum Disulfide: A 2D, Few‐Layer Transition‐Metal Thiophosphate and Its Hydrogen Evolution Reaction Activity over a Wide pH Range
Authors: Jenjeti Ramesh Naidu , Austeria Muthu P. , Sampath Srinivasan
Published: July 2016

A two‐dimensional, few‐layer nickel thiophosphate, NiPS3, was introduced as a hydrogen evolution reaction catalyst from aqueous acidic, alkaline, and neutral solutions. NiPS3 is semiconducting in nature, and its band structure calculations revealed the importance of the [P2S6]4− units in the adsorption of hydrogen and subsequent evolution. Onset potentials of −0.062, −0.065, and −0.298 V versus RHE were observed in acidic, alkaline, and neutral media. Tafel slopes of 55, 48, and 94 mV dec−1 and exchange current densities of 1.8×10−4, 6.1×10−4, and 3.2×10−5 A cm−2 were observed in aqueous 0.5 m H2SO4, 1 m KOH, and 3.5 % NaCl solutions, respectively. The catalyst was found to be very stable, and the constituting elements are earth abundant. The present study opens up a new class of semiconducting layered materials to catalyze various redox reactions. Achieving a single layer will be of great interest to electrical and magnetic devices.
Hydrogen‐Bond and Supramolecular‐Contact Mediated Fluorescence Enhancement of Electrochromic Azomethines
Authors: Wałęsa‐Chorab Monika , Tremblay Marie‐Hélène , Skene William G.
Published: July 2016

An electronic push–pull fluorophore consisting of an intrinsically fluorescent central fluorene capped with two diaminophenyl groups was prepared. An aminothiophene was conjugated to the two flanking diphenylamines through a fluorescent quenching azomethine bond. X‐ray crystallographic analysis confirmed that the fluorophore formed multiple intermolecular supramolecular bonds. It formed two hydrogen bonds involving a terminal amine, resulting in an antiparallel supramolecular dimer. Hydrogen bonding was also confirmed by FTIR and NMR spectroscopic analyses, and further validated theoretically by DFT calculations. Intrinsic fluorescence quenching modes could be reduced by intermolecular supramolecular contacts. These contacts could be engaged at high concentrations and in thin films, resulting in fluorescence enhancement. The fluorescence of the fluorophore could also be restored to an intensity similar to its azomethine‐free counterpart with the addition of water in >50 % v/v in tetrahydrofuran (THF), dimethyl sulfoxide (DMSO), and acetonitrile. The fluorophore also exhibited reversible oxidation and its color could be switched between yellow and blue when oxidized. Reversible electrochemically mediated fluorescence turn‐off on turn‐on was also possible.
Metal Oxide Assisted Preparation of Core–Shell Beads with Dense Metal–Organic Framework Coatings for the Enhanced Extraction of Organic Pollutants
Authors: del Rio Mateo , Palomino Cabello Carlos , Gonzalez Veronica , Maya Fernando , Parra Jose B. , Cerdà Victor , Turnes Palomino Gemma
Published: July 2016

Dense and homogeneous metal–organic framework (MOF) coatings on functional bead surfaces are easily prepared by using intermediate sacrificial metal oxide coatings containing the metal precursor of the MOF. Polystyrene (PS) beads are coated with a ZnO layer to give ZnO@PS core–shell beads. The ZnO@PS beads are reactive in the presence of 2‐methylimidazole to transform part of the ZnO coating into a porous zeolitic imidazolate framework‐8 (ZIF‐8) external shell positioned above the internal ZnO precursor shell. The obtained ZIF‐8@ZnO@PS beads can be easily packed in column format for flow‐through applications, such as the solid‐phase extraction of trace priority‐listed environmental pollutants. The prepared material shows an excellent permeance to flow when packed as a column to give high enrichment factors, facile regeneration, and excellent reusability for the extraction of the pollutant bisphenol A. It also shows an outstanding performance for the simultaneous enrichment of mixtures of endocrine disrupting chemicals (bisphenol A, 4‐tert‐octylphenol and 4‐n‐nonylphenol), facilitating their analysis when present at very low levels (<1 μg L−1) in drinking waters. For the extraction of the pollutant bisphenol A, the prepared ZIF‐8@ZnO@PS beads also show a superior extraction and preconcentration capacity to that of the PS beads used as precursors and the composite materials obtained by the direct growth of ZIF‐8 on the surface of the PS beads in the absence of metal oxide intermediate coatings.
The Catalytic Mechanism of the Marine‐Derived Macrocyclase PatGmac
Authors: Brás Natércia F. , Ferreira Pedro , Calixto Ana R. , Jaspars Marcel , Houssen Wael , Naismith James H. , Fernandes Pedro A. , Ramos Maria J.
Published: July 2016

Cyclic peptides are a class of compounds with high therapeutic potential, possessing bioactivities including antitumor and antiviral (including anti‐HIV). Despite their desirability, efficient design and production of these compounds has not been achieved to date. The catalytic mechanism of patellamide macrocyclization by the PatG macrocyclase domain has been computationally investigated by using quantum mechanics/molecular mechanics methodology, specifically ONIOM(M06/6‐311++G(2d,2p):ff94//B3LYP/6‐31G(d):ff94). The mechanism proposed herein begins with a proton transfer from Ser783 to His 618 and from the latter to Asp548. Nucleophilic attack of Ser783 on the substrate leads to the formation of an acyl–enzyme covalent complex. The leaving group Ala‐Tyr‐Asp‐Gly (AYDG) of the substrate is protonated by the substrate's N terminus, leading to the breakage of the P1−P1′ bond. Finally, the substrate's N terminus attacks the P1 residue, decomposing the acyl–enzyme complex forming the macrocycle. The formation and decomposition of the acyl–enzyme complex have the highest activation free energies (21.1 kcal mol−1 and 19.8 kcal mol−1 respectively), typical of serine proteases. Understanding the mechanism behind the macrocyclization of patellamides will be important to the application of the enzymes in the pharmaceutical and biotechnological industries.
NOUF6 Revisited: A Comprehensive Study of a Hexafluoridouranate(V) Salt
Authors: Scheibe Benjamin , Lippert Sina , Rudel Stefan S. , Buchner Magnus R. , Burghaus Olaf , Pietzonka Clemens , Koch Martin , Karttunen Antti J. , Kraus Florian
Published: July 2016

We have synthesized NOUF6 by direct reaction of NO with UF6 in anhydrous HF (aHF). Based on the unit cell volume and powder diffraction data, the compound was previously reported to be isotypic to O2PtF6, however, detailed structural data, such as the atom positions and all information that can be derived from those, were unavailable. We have therefore investigated the compound by using single‐crystal and powder X‐ray diffraction, IR, Raman, NMR, EPR, and photoluminescence spectroscopy, magnetic measurements, as well as chemical analysis, density determination, and quantum chemical calculations.
One‐Step Production of 1,3‐Butadiene from 2,3‐Butanediol Dehydration
Authors: Liu Xi , Fabos Viktoria , Taylor Stuart , Knight David W. , Whiston Keith , Hutchings Graham J.
Published: July 2016

We report the direct production of 1,3‐butadiene from the dehydration of 2,3‐butandiol by using alumina as catalyst. Under optimized kinetic reaction conditions, the production of methyl ethyl ketone and isobutyraldehyde, formed via the pinacol–pinacolone rearrangement, was markedly reduced and almost 80 % selectivity to 1,3‐butadiene and 1,3‐butadiene could be achieved. The presence of water plays a critical role in the inhibition of oligomerization. The amphoteric nature of γ‐Al2O3 was identified as important and this contributed to the improved catalytic selectivity when compared with other acidic catalysts.
A Short Synthesis of Aphanamol I in Both Racemic and Enantiopure Forms
Authors: Ferrara Steven J. , Burton Jonathan W.
Published: July 2016

A short synthesis of the biologically active sesquiterpene natural product (+)‐aphanamol I in both racemic and enantiopure forms is reported. Key steps include: a catalytic enantioselective conjugate addition, an oxidative radical cyclization, and a ring‐expanding Claisen rearrangement.
ChemInform Abstract: Recyclable and Selective Nitroarene Hydrogenation Catalysts Based on Carbon‐Coated Cobalt Oxide Nanoparticles.
Authors: Chen Bingfeng , Li Fengbo , Huang Zhijun , Yuan Guoqing
Published: July 2016

A title new nanoparticles are synthesized and characterized.
ChemInform Abstract: Facile Microwave‐Assisted Synthesis of 1,3,5‐Trisubstituted Pyrazoline Derivatives Incorporating Sulfonyl Moiety.
Authors: Liu Fei , Yang Jin‐Feng , Liu Hong , Wei Wen‐Zhen , Ma Yan‐Mei
Published: July 2016

The microwave‐assisted cyclization of chalcones, obtained by condensation of aromatic aldehydes with acetophenones furnishes trisubstituted pyrazoline derivatives.
ChemInform Abstract: Selective Elaboration of Aminodiols Towards Small Ring α‐ and β‐Amino Acid Derivatives that Incorporate an Aziridine, Azetidine, or Epoxide Scaffold.
Authors: Semina Elena , Zukauskaite Asta , Sackus Algirdas , De Kimpe Norbert , Mangelinckx Sven
Published: July 2016

The osmium‐catalyzed dihydroxylation of aminomethylacrylates (I) affords functionalized diols of type (II) which are elaborated to yield 2‐(aminomethyl)oxirane‐2‐carboxylates, aziridine‐2‐carboxylates, and azetidine‐3‐carboxylates.
Entwicklung eines skalierbaren Brenners zum Betrieb mit reinem Wasserstoff
Authors: Peña Jorge Luis Juárez , Dischinger Norbert , Keim Ernst , te Nijenhuis Jan Willen , Volkert Jochen , Müller Karsten
Published: July 2016

Verschiedene vormischende Brenner wurden für den Betrieb mit reinem Wasserstoff theoretisch und experimentell untersucht. Für die Auslegung wurden Berechnungen der Péclet‐Zahl durchgeführt. Die untersuchten Austrittsquerschnitte bei unterschiedlichen Vorwärmungstemperaturen des Gasgemischs und stöchiometrischer Mischung erwiesen sich als unterkritisch. Es konnte ein flammenrückschlagsfreier Betrieb des Brenners für eine Anströmgeschwindigkeit der Gasmischung von größer 12 m s−1 nachgewiesen werden. Der vormischende Brenner für reinen Wasserstoff zeigte eine stabile Verbrennung im Betrieb.
Measuring and modelling the peculiarities of aqueous‐phase radical polymerization
Authors: Preusser Calista , Hutchinson Robin A.
Published: July 2016

The application of specialized pulsed‐laser techniques has led to a vastly improved understanding of the kinetics of aqueous phase solution radical polymerization of water‐soluble monomers. Propagation rate coefficients vary significantly with monomer concentration, an effect unique to the aqueous environment. In addition, the formation and reaction of mid‐chain radicals affects polymerization rates, and thus polymer molar masses, in acrylamide and acrylic acid systems. This perspective provides an overview of these mechanistic peculiarities, which have been captured in kinetic models developed to represent the homopolymerizations of N‐vinyl pyrrolidone, N‐vinyl formamide, methacrylic acid, acrylic acid, and acrylamide over a wide range of conditions. The batch studies demonstrate the importance of these effects in aqueous polymerization and the validity of the rate coefficients taken from the independent kinetic studies.
5‐hydroxymethylcytosine marks postmitotic neural cells in the adult and developing vertebrate central nervous system
Authors: Diotel Nicolas , Mérot Yohann , Coumailleau Pascal , Gueguen Marie‐Madeleine , Sérandour Aurélien A. , Salbert Gilles , Kah Olivier
Published: July 2016

The epigenetic mark 5‐hydroxymethylcytosine (5hmC) is a cytosine modification that is abundant in the central nervous system of mammals and which results from 5‐methylcytosine oxidation by TET enzymes. Such a mark is suggested to play key roles in the regulation of chromatin structure and gene expression. However, its precise functions still remain poorly understood and information about its distribution in non‐mammalian species is still lacking. Here, the distribution of 5hmC was investigated in the brain of adult zebrafish, African claw frog, and mouse in a comparative manner. We show that zebrafish neurons are endowed with high levels of 5hmC, whereas quiescent or proliferative neural progenitors show low to undetectable levels of the modified cytosine. In the brain of larval and juvenile Xenopus, 5hmC is also detected in neurons, while ventricular proliferative cells do not display this epigenetic mark. Similarly, 5hmC is enriched in neurons compared to neural progenitors of the ventricular zone in the mouse developing cortex. Interestingly, 5hmC colocalized with the methylated DNA binding protein MeCP2 and with the active chromatin histone modification H3K4me2 in mouse neurons. Taken together, our results show an evolutionarily conserved cerebral distribution of 5hmC between fish and tetrapods and reinforce the idea that 5hmC fulfills major functions in the control of chromatin activity in vertebrate neurons. J. Comp. Neurol. 525:478–497, 2017. © 2016 Wiley Periodicals, Inc.
Characterization of Interfacial Charge‐Transfer Photoexcitation of Polychromium‐Oxo‐Electrodeposited TiO2 as an Earth‐Abundant Photoanode for Water Oxidation Driven by Visible Light
Authors: Chandra Debraj , Tsuriya Ryougen , Sato Tsubasa , Takama Daisuke , Abe Naoto , Kajita Masashi , Li Dong , Togashi Takanari , Kurihara Masato , Saito Kenji , Yui Tatsuto , Yagi Masayuki
Published: July 2016

Polychromium‐oxo‐deposited TiO2 (CrIIIxOy/TiO2) electrodes were fabricated by a simple electrochemical technique by using different TiO2 basal electrodes (anatase, rutile, and mixed polymorphic phases P25) as earth‐abundant photoanodes for visible‐light‐driven water oxidation. The high‐resolution transmission electron microscopy (HR‐TEM) observation illustrated that an CrIIIxOy layer with approximately 2–3 nm thickness was formed on the surface of the crystalline TiO2 particles. Upon visible‐light irradiation of the electrodes, the photoanodic current based on water oxidation was generated at the CrIIIxOy/TiO2 electrodes. However, the wavelength (below 620 nm) for photocurrent generation at CrIIIxOy/TiO2‐rutile was longer than that (below 560 nm) at CrIIIxOy/TiO2‐P25 by 60 nm, which is in agreement with the difference (0.2 eV) in the conduction band (CB) edge energy between rutile and anatase TiO2. This gives a quantitative account for the photocurrent generation based on interfacial charge transfer (IFCT) from Cr 3d of the deposited CrIIIxOy layer to the TiO2 CB. The photocurrent generated for CrIIIxOy/TiO2‐rutile was higher than that for CrIIIxOy/TiO2‐anatase, which is ascribed to 1) more effective CrIIIxOy deposition on the rutile particles, 2) a larger electrolyte/CrIIIxOy interface for water oxidation as a result of smaller rutile particles (ca. 30–40 nm) compared with larger P25 particles (ca. 40–80 nm), and 3) more effective use of visible light owing to the low energy IFCT transition of rutile.
Low Cytotoxic Metal–Organic Frameworks as Temperature‐Responsive Drug Carriers
Authors: Lin Wenxin , Hu Quan , Yu Jiancan , Jiang Ke , Yang Yanyu , Xiang Shengchang , Cui Yuanjing , Yang Yu , Wang Zhiyu , Qian Guodong
Published: July 2016

Invited for this month's cover is the group of Prof. Guodong Qian from Zhejiang University, China. The cover picture shows low cytotoxic metal–organic frameworks (MOFs) used as drug carriers, whose drug release behavior can be tuned by controlling the temperature. Read the full text of the article at 10.1002/cplu.201600142.
A Longitudinal HbA1c Model Elucidates Genes Linked to Disease Progression on Metformin
Authors: Goswami S , Yee SW , Xu F , Sridhar SB , Mosley JD , Takahashi A , Kubo M , Maeda S , Davis RL , Roden DM , Hedderson MM , Giacomini KM , Savic RM
Published: July 2016

One‐third of type‐2 diabetic patients respond poorly to metformin. Despite extensive research, the impact of genetic and nongenetic factors on long‐term outcome is unknown. In this study we combine nonlinear mixed effect modeling with computational genetic methodologies to identify predictors of long‐term response. In all, 1,056 patients contributed their genetic, demographic, and long‐term HbA1c data. The top nine variants (of 12,000 variants in 267 candidate genes) accounted for approximately one‐third of the variability in the disease progression parameter. Average serum creatinine level, age, and weight were determinants of symptomatic response; however, explaining negligible variability. Two single nucleotide polymorphisms (SNPs) in CSMD1 gene (rs2617102, rs2954625) and one SNP in a pharmacologically relevant SLC22A2 gene (rs316009) influenced disease progression, with minor alleles leading to less and more favorable outcomes, respectively. Overall, our study highlights the influence of genetic factors on long‐term HbA1c response and provides a computational model, which when validated, may be used to individualize treatment.
Synthesis, Characterization, and Cross‐Linking Strategy of a Quercetin‐Based Epoxidized Monomer as a Naturally‐Derived Replacement for BPA in Epoxy Resins
Authors: Kristufek Samantha L. , Yang Guozhen , Link Lauren A. , Rohde Brian J. , Robertson Megan L. , Wooley Karen L.
Published: July 2016

The natural polyphenolic compound quercetin was functionalized and cross‐linked to afford a robust epoxy network. Quercetin was selectively methylated and functionalized with glycidyl ether moieties using a microwave‐assisted reaction on a gram scale to afford the desired monomer (Q). This quercetin‐derived monomer was treated with nadic methyl anhydride (NMA) to obtain a cross‐linked network (Q‐NMA). The thermal and mechanical properties of this naturally derived network were compared to those of a conventional diglycidyl ether bisphenol A‐derived counterpart (DGEBA‐NMA). Q‐NMA had similar thermal properties [i.e., glass transition (Tg) and decomposition (Td) temperatures] and comparable mechanical properties (i.e., Young's Modulus, storage modulus) to that of DGEBA‐NMA. However, it had a lower tensile strength and higher flexural modulus at elevated temperatures. The application of naturally derived, sustainable compounds for the replacement of commercially available petrochemical‐based epoxies is of great interest to reduce the environmental impact of these materials. Q‐NMA is an attractive candidate for the replacement of bisphenol A‐based epoxies in various specialty engineering applications.
Intrathyroidal parathyroid adenoma: Diagnostic pitfalls on fine‐needle aspiration: Two case reports and literature review
Authors: Shi Chang , Guan Hongwei , Qi Wenjing , Ji Jialin , Wu Jialing , Yan Feng , Wang Huali
Published: July 2016

Parathyroid adenomas may occur within the thyroid, clinically simulating thyroid nodules. Fine‐needle aspiration (FNA) of these presumably “thyroid nodules” can lead to misinterpretation of cytomorphological findings because of similarities in cytological features of parathyroid and thyroid lesions. Here, we reported two cases of intrathyroidal parathyroid adenomas. One of them was misinterpreted as thyroid lesions. The other was composed exclusively of oncocytic cells and had a correct cytological diagnosis. In this study, both cases showed a new cytological feature which has not been reported in the literature: many capillaries protruding outside the three‐dimensional fragments without epithelial cells around. Diagn. Cytopathol. 2016;44:921–925. © 2016 Wiley Periodicals, Inc.
A Method of Peculiarity Factor Approximation Using Vector Quantization Model
Authors: SAITOH FUMIAKI , ISHIZU SYOHEI
Published: July 2016

The purpose of this research is to reduce the computational complexity of the peculiarity factor (PF). Recently, PF has been adopted as the index for anomaly data detection, and it is widely used in various mining scenes. The fact that PF has become a powerful mining tool is positive because its calculation method is extremely simple and the results of the calculation are easy to understand visually. One of the most important problems for using PF for large‐scale data is the rapidly increasing computational complexity required when the data volume increases. The computational complexity of PF is in the polynomial order because the PF of each data is calculated distantly over all the data. In this study, we propose an approximation methodology for PF for computational reduction and for enhanced robustness using the vector quantization model. Approximate values of PF are calculated by replacing the actual data with the nodes of vector quantization model. By calculating PF based on the vector quantization node vectors, we achieve restraint in the increasing computational complexity.
Radio Frequency Field Dependence of Microwave‐Assisted Switching Behaviors of Co/Pt Nanodots
Authors: FURUTA MASAKI , OKAMOTO SATOSHI , KIKUCHI NOBUAKI , KITAKAMI OSAMU , SHIMATSU TAKEHITO
Published: July 2016

Microwave‐assisted magnetization switching (MAS) has been expected as one of the prominent future ultra‐high‐density magnetic recording technologies. In this paper, we have studied the radio frequency (RF) field dependence of the switching behavior of Co/Pt nanodot arrays with various dot diameters. While the critical frequency increases and the minimum switching field decreases with increasing the RF field, MAS behavior critically depends on the dot size. For small dots less than 130 nm in diameter, the critical frequency and the minimum switching field exhibit linear variation with the RF field. On the other hand, for the larger dots (dot diameter ≥ 230 nm), they exhibit not only profound MAS effect but also obvious change in the behavior at a certain RF field. These changes of MAS behaviors are explained as a consequence of the change of magnetization precession mode. On the other hand, the dispersions of MAS effect exhibit no remarkable variation on the RF field.
Polyhedral Bismuth Polycations Coordinating Gold(I) with Varied Hapticity in a Homoleptic Heavy‐Metal Cluster
Authors: Müller Ulrike , Isaeva Anna , Richter Janine , Knies Maximilian , Ruck Michael
Published: July 2016

Shiny black, air‐sensitive crystals of [Au(Bi8)2](AlCl4)5were obtained from the reaction of AuCl, BiCl3, and bismuth in the ionic liquid [BMIm]Cl·4AlCl3(BMIm = 1‐n‐butyl‐3‐methylimidazolium) at 180 °C. [Au(Bi8)2](AlCl4)5crystallizes in the monoclinic space groupP21/n. In the heavy‐metal cluster [Au(Bi8)2]5+, two square‐antiprismatic Bi82+polycations coordinate the gold(I) atom in η2‐ and η4‐mode, respectively. Quantum chemical calculations demonstrate that both Bi82+polycations involve skeletal electrons for the donor bonding, which causes a widening of Bi–Bi distances compared with those in free Bi82+.
First Evidence of a Water‐Soluble Plutonium(IV) Hexanuclear Cluster
Authors: Tamain Christelle , Dumas Thomas , Guillaumont Dominique , Hennig Christoph , Guilbaud Philippe
Published: July 2016

The singular PuIV hexanuclear cluster [Pu6(OH)4O4]12+ stabilized by 1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid (DOTA) ligands was structurally characterized for the first time both in the solid state and in water solution by using X‐ray diffraction and X‐ray absorption and UV/Vis spectroscopy. The stability of this cluster in water and its high solubility over a large pH range are of upmost importance for plutonium environmental speciation with potential applications in a related migration model.
Simple Primary Amino Amide Organocatalyst for Enantioselective Aldol Reactions of Isatins with Ketones
Authors: Kimura Jo , Subba Reddy Ummareddy Venkata , Kohari Yoshihito , Seki Chigusa , Mawatari Yasuteru , Uwai Koji , Okuyama Yuko , Kwon Eunsang , Tokiwa Michio , Takeshita Mitsuhiro , Iwasa Tatsuo , Nakano Hiroto
Published: July 2016

Enantioselective aldol reactions of various isatins with ketones using newly designed amino amide organocatalysts were found to provide chiral 3‐substituted 3‐hydroxy‐2‐oxindoles in good to excellent yields and with excellent stereoselectivities (up to 99 %, up to 98 % ee, syn/anti = 99:1); one catalyst, 3i, proved particularly successful. One of the resulting oxindoles, 3‐hydroxy‐3‐(2‐oxocyclohexyl)‐2‐indolinone may serve as a synthetic intermediate for pharmaceutically important compounds and, in its own right, shows interesting anticonvulsant activities.
Iron‐Catalyzed Synthesis of Five‐Membered Cyclic Carbonates from Vicinal Diols: Urea as Sustainable Carbonylation Agent
Authors: Peña‐López Miguel , Neumann Helfried , Beller Matthias
Published: July 2016

A new iron‐catalyzed synthesis of cyclic carbonates from the corresponding vicinal diols and urea is described. This straightforward transformation allows for the preparation of a variety of five‐membered carbonates by employing an inexpensive and environmentally benign iron salt as the catalyst. The use of readily available feedstocks such as urea and polyols makes this a sustainable process. As ammonia is formed as the only stoichiometric byproduct, this process can also be characterized by its high atom economy.
Electrical Cable‐based Copper Disk Electrodes as Oxidase Biosensor Platforms with Cathodic H2O2 Readout
Authors: Jaikaew Wajee , Patanakul Rungrueang , Schulte Albert
Published: July 2016

We report the first utilization of copper disk electrodes as suitable cathodic transducer platforms for glucose biosensors. Simple and cheap Cu disk electrodes were fabricated from ordinary electrical cable by cementing into a glass tube with epoxy resin and subsequent polishing to expose the active area. Glucose oxidase was immobilized on the electrode tips by entrapment in dropped and dried polymeric Nafion deposits. At a H2O2 detection potential of −0.15 V vs. a reference electrode, the linear response range of fabricated cable Cu glucose biosensors was 20–1500 µM, with a sensitivity of about 700 nA µM−1 cm−2. Quantitative analysis of glucose‐supplemented buffer solutions showed a recovery of 106±4 % (n=3). The principal advantage of the glucose biosensors described in this study, compared to other options, is the simplicity of the cathodic H2O2 readout, which exploits cheap and readily available electrical cable, without any extra surface modification with catalytically active micro‐ or nanomaterials. The analytical performance of the biosensor is competitive and suggests potential applications in routine glucose testing, in particular in academic teaching and research laboratories. The work is also a starting point for transfer of the methodology from simple cable Cu electrodes to arrays of miniaturized Cu sensors, using a combination of microlithography, electroforming and molding (LIGA).
Combining different assays and chemical analysis to characterize the genotoxicity of waters impacted by textile discharges
Authors: Vacchi Francine I. , Vendemiatti Josiane A. S. , Brosselin Vanessa , Ferreira da Silva Bianca , B. Zanoni Maria Valnice , DeMeo Michel , Bony Sylvie , Devaux Alain , Umbuzeiro Gisela A.
Published: July 2016

Waters receiving textile discharges can exhibit genotoxic and mutagenic activity, which has been related to the presence of dyes and aromatic amines as synthesis precursors or byproducts. The aim of this study was to identify dyes and aromatic amines in water samples impacted by textile discharges, and to evaluate the genotoxic responses of these samples using the Salmonella/microsome assay in strains TA98 and YG1041, and the Fpg‐modified comet assay in the RTL‐W1 fish cell line. The genotoxicity of river samples downstream of the discharge was greater than the upstream samples in both of the Ames tests. The Fpg‐modified comet assay detected similar levels of DNA damage in the upstream and downstream samples. Mutagenicity was not detected with TA98, except for the Quilombo River samples, but when YG1041 was used as the tester strain mutagenicity was detected for all sites with a very different profile in upstream sites relative to the other sites. The mutagenic response strongly indicated that aromatic amines or dyes were contributing to the mutagenic activity downstream. The impact of textile discharges was also confirmed by chemical analysis, because the highest concentrations of azo dyes and aromatic amines were detected in the river downstream. This study shows the value of combining assays measuring complementary endpoints to better characterize the mutagenicity of environmental samples, with the advantage that this approach provides an indication of what classes of compounds are responsible for the effect. Environ. Mol. Mutagen. 57:559–571, 2016. © 2016 Wiley Periodicals, Inc.
Reduction and reuse of Fe–Ni bimetallic nanoparticles oxide and evaluating its ability in acid red 14 removal
Authors: Niksefat Marzieh , Ayati Bita
Published: July 2016

In this study, an innovative method was investigated for resloving the problem involved in iron–nickel nanoparticles reuse in dye removal. The completely oxidized nanoparticles, once used for dye removal, were separated from the solution and reduced with different concentrations of sodium borohydride. After SEM and EDAX analyses, 54 experiments were carried out using RSM method by applying Box–Behnken model. The obtained high coefficient of determination and very small P‐value (<0.0001) demonstrated that the model was appropriate to characterize the actual relationship between the response and input values. In this model, six independent variables including sodium borohydride concentration, contact time, shaking speed, time passed from oxidation, dye concentration, and nanoparticles concentration were studied to optimize the removal of Acid Red 14. According to ANOVA analyses and the obtained graphs, it was observed that the shaking speed of reducer solution and nanoparticles concentration were the most effective parameters, whereas the interval between oxidation of nanoparticles and their further reduction had no significant impact on removal efficiency. By maximum dye removal with the lowest reducer and nanoparticles concentration in optimum conditions predicted by the model ([NaBH4] = 2 g L−1, contact time = 104 min, shaking speed = 43 rpm, time passed = 0 day, [dye] = 200 mg L−1, [NPs] = 0.4 g L−1), the removal efficiency of 92.57% would be achieved. © 2016 American Institute of Chemical Engineers Environ Prog, 35: 1646–1656, 2016
Self‐adjustment in rivers: Evidence for least action as the primary control of alluvial‐channel form and process
Authors: Nanson Gerald C. , Huang He Qing
Published: July 2016

Least action principle (LAP) in rivers is demonstrated by maximum flow efficiency (MFE) and is the foundation of variational mechanics based on energy and work rather than Newtonian force and momentum. Empirical evidence shows it to be the primary control for the adjustment of alluvial channels. Because most rivers flow with imposed water and sediment loads down valley gradients they have largely inherited, they self‐regulate energy expenditure to match the work they are required to do to remain stable. Overpowered systems develop a variety of channel patterns to expend excess energy and remain stable. Australia offers an opportunity to study low‐energy rivers closely adjusted to very low continental gradients. The anabranching Marshall and single‐thread Plenty Rivers flow down nearly straight channels with average H numbers [ratio between excess bed shear and width/depth (W/D) ratio] close to the optimum of 0.3 for stationary equilibrium. Ridge‐form divisions of the original channel width create anabranches that radically alter W/D ratios relative to bed shear, the same being true for short‐wide islands on the large low‐gradient Yangtze River in China. In contrast, Mount Chambers Creek in Australia's tectonically more active Flinders Ranges is accreting an alluvial fan with unstable distributary channels exhibiting H numbers well below the optimum. LAP also explains profound biases in Earth's stratigraphic record. Because meandering is an energy‐shedding mechanism, sinuous rivers sequester relatively little sediment resulting in all sequences being just a few tens of metres thick. In contrast, low‐energy braided disequilibrium systems can sequester sediment piles over a kilometre in thickness and tens of kilometres wide. LAP provides a new paradigm for river research by identifying the attractor state controlling river channel evolution. It links advances in theoretical physics to fluvial geomorphology, stratigraphy and hydraulic engineering and opens opportunities for diverse investigations in Earth system science. Copyright © 2016 John Wiley & Sons, Ltd.