bluuebunny/crossref_metadata_2025_split huggingface dataset:
[M(CO)4(2,2′‐bipyridine)] (M=Cr, Mo, W) Complexes as Efficient Catalysts for Electrochemical Reduction of CO2 at a Gold Electrode
Authors: Tory Joanne , Setterfield‐Price Briony , Dryfe Robert A. W. , Hartl František 
Published: September 2014

AbstractGroup 6 complexes of the type [M(CO)4(bpy)] (M=Cr, Mo, W) are capable of behaving as electrochemical catalysts for the reduction of CO2 at potentials less negative than those for the reduction of the radical anions [M(CO)4(bpy)].−. Cyclic voltammetric, chronoamperometric and UV/Vis/IR spectro‐electrochemical data reveal that five‐coordinate [M(CO)3(bpy)]2− are the active catalysts. The catalytic conversion is significantly more efficient in N‐methyl‐2‐pyrrolidone (NMP) compared to tetrahydrofuran, which may reflect easier CO dissociation from 1e−‐reduced [M(CO)4(bpy)].− in the former solvent, followed by second electron transfer. The catalytic cycle may also involve [M(CO)4(H‐bpy)]− formed by protonation of [M(CO)3(bpy)]2−, especially in NMP. The strongly enhanced catalysis using an Au working electrode is remarkable, suggesting that surface interactions may play an important role, too.
Controlled Synthesis of Porous Coordination‐Polymer Microcrystals with Definite Morphologies and Sizes under Mild Conditions
Authors: Liu Qing , Yang Ji‐Min , Jin Li‐Na , Sun Wei‐Yin 
Published: September 2014

AbstractHerein, we report a facile and convenient method for the synthesis of the porous coordination polymer MOF‐14 [Cu3(BTB)2] (H3BTB=4,4′,4′′‐benzene‐1,3,5‐triyl‐tribenzoic acid) as microcrystals with definite shapes and crystal facets controlled by the reaction medium at room temperature. The amount of sodium acetate added to the reaction system plays a crucial role in the shape evolution of MOF‐14 from rhombic dodecahedrons to truncated rhombic dodecahedrons and cubes with truncated edges and then to cubes. The addition of a base could accelerate the formation rate of crystal growth and increase the supersaturation of crystal growth, thus resulting in the formation of MOF‐14 cube crystals with high‐energy crystal facets. The morphological evolution was also observed for HKUST‐1 [Cu3(BTC)2] (H3BTC=1,3,5‐benzenetricarbocylic acid) from octahedrons to cubes, thus verifying the probable mechanism of the morphological transformation. The gas‐adsorption properties of MOF‐14 with different shapes were studied and reveal that the porous coordination‐polymer microcrystals display excellent and morphology‐dependent sorption properties.
Simultaneously Sizing and Quantitating Zeptomole‐Level DNA at High Throughput in Free Solution
Authors: Zhu Zaifang , Chen Huang , Chen Apeng , Lu Joann J. , Liu Shaorong , Zhao Meiping 
Published: September 2014

AbstractDetermining the sizes and measuring the quantities of DNA molecules are fundamental tasks in molecular biology. DNA sizes are usually evaluated by gel electrophoresis, but this method cannot simultaneously size and quantitate a DNA at low zeptomole (zmol) levels of concentration. We have recently developed a new technique, called bare‐narrow‐capillary/hydrodynamic‐chromatography or BaNC‐HDC, for resolving DNA based on their sizes without using any sieving matrices. In this report, we utilize BaNC‐HDC for measuring the sizes and quantities of DNA fragments at zmol to several‐molecule levels of concentration. DNA ranging from a few base pairs to dozens of kilo base pairs are accurately sized and quantitated at a throughput of 15 samples per hour, and each sample contains dozens of DNA strands of different lengths. BaNC‐HDC can be a cost‐effective means and an excellent tool for high‐throughput DNA sizing and quantitation at extremely low quantity level.
Versatile and Sustainable Synthesis of Cyclic Imides from Dicarboxylic Acids and Amines by Nb2O5 as a Base‐Tolerant Heterogeneous Lewis Acid Catalyst
Authors: Ali Md. Ayub , Siddiki S. M. A. Hakim , Kon Kenichi , Hasegawa Junya , Shimizu Ken‐ichi 
Published: September 2014

AbstractCatalytic condensation of dicarboxylics acid and amines without excess amount of activating reagents is the most atom‐efficient but unprecedented synthetic method of cyclic imides. Here we present the first general catalytic method, proceeding selectively and efficiently in the presence of a commercial Nb2O5 as a reusable and base‐tolerant heterogeneous Lewis acid catalyst. The method is effective for the direct synthesis of pharmaceutically or industrially important cyclic imides, such as phensuximide, N‐hydroxyphthalimide (NHPI), and unsubstituted cyclic imides from dicarboxylic acid or anhydrides with amines, hydroxylamine, or ammonia.
Selective hydrogenation of 3,4‐dimethoxybenzophenone in liquid phase over Pd/C catalyst in a slurry reactor
Authors: Tiwari Manishkumar S. , Yadav Ganapati D. , Ng Flora T. T. 
Published: September 2014

AbstractSelective hydrogenation of benzophenone to benzhydrol is industrially relevant. In the current work, selective hydrogenation of 3,4‐dimethoxybenzophenone (3,4‐DMBP) to 3,4‐dimethoxybenzhydrol (3,4‐DMBH) was investigated over 5 % w/w Pd/C and 5 % w/w Pt/C as catalysts in a slurry reactor. The effects of hydrogen partial pressure (0.2–1 MPa), catalyst loading (2.0 × 10−4to 8.0 × 10−4 g/cm3), initial concentration of 3,4‐dimethoxybenzophenone (5.0 × 10−6to 1.5 × 10−4 mol/cm3) and temperature (40–70 °C) on rate of reaction and selectivity were studied. Effect of solvent such as methanol, ethanol, 2‐propanol and tetrahydrofuran (THF) was also investigated. 5 % w/w Pd/C was the better catalyst with THF as the best solvent, which gave 100 % conversion and 80 % selectivity in 1 h for 0.5 MPa hydrogen pressure at 60 °C. The Langmuir‐Hinshelwood‐Hougen‐Watson model was fitted. The intrinsic kinetics and mechanism of hydrogenation were established.
Development of a new family of food packaging bioplastics from cross‐linked gelatin based films
Authors: Biscarat Jennifer , Charmette Christophe , Sanchez José , Pochat‐Bohatier Céline 
Published: September 2014

AbstractThe purpose of this work was to develop green bioplastic preparation process from gelatin by using solvent‐free approach with efficient use of resources. Film plasticizing was achieved by adding polyethylene glycol (Mw = 200 g.mol−1). Different cross linking agents – glutaraldehyde (GTA), N‐hydroxysuccinimide (NHS), Bis(succinimidyl)nona(ethylene glycol) (BS(PEG)9) and ferulic acid (FA) were tested to obtain water resistant films suitable for gas permeability characterization. Functional properties (mechanical and gas transfer properties) of gelatin‐based films were determined. Gelatin films cross‐linked with FA presented very good gas barrier properties (48 and 175 cm3.µm/m2.day.kPa respectively for O2 and CO2), compared to synthetic polymers, equivalent to polar polymer like nylon 6 or polyethylene terephthalate and better than non‐polar polymers like high density or low density polyethylene. Swelling ratio measurements in water displayed gelatin/FA films resisted to water without breaking during 4 h compared to 1.5 h for pure gelatin films. Films could support saturated water vapour environment at 20 °C during 15 days without breaking. Gelatin/PEG200 films presented very good permselectivity towards CO2 and O2 (14.5). This value was reduced to 8 when cross‐linked with FA, and to 4 after PEG200 addition, presenting still interesting level. All these results confirmed that gelatin is a promising biobased polymer to prepare food packaging films.
Two Cluster‐Based Coordination Polymers Derived from [Et4N][Tp*WS3(CuBr)3] and CuCN: Isolation, Structures and Amplified Third‐Order Nonlinear Optical Responses
Authors: Liu Quan , Zhang Wenhua , Sun Zhenrong , Lang Jianping 
Published: September 2014

AbstractTreatment of a W/Cu/S precursor [Et4N][Tp*WS3(CuBr)3] (1) with three equiv. of CuCN in DMF/MeCN/benzonitrile (or α‐tolunitrile) yielded two [Tp*WS3Cu3(µ3‐DMF)]‐based coordination polymers, [Tp*WS3Cu3(µ3‐DMF)(CN)3Cu]2·2DMF (2·2DMF) and [Tp*WS3Cu3(µ3‐DMF)(CN)3Cu(α‐tolunitrile)]2·3MeCN (3·3MeCN), respectively. Structural analysis revealed that 2 adopts a 2D network with a 4.82 topology while 3 has a 1D ladder‐type chain. The third‐order nonlinear optical responses of 2 and 3 in DMF were 10 times enhanced compared to those of the precursor cluster 1.
Asymmetric Pudovik Reaction of Chiral Fluoroalkyl α,β‐Unsaturated Ketimines and Diphenyl Phosphite
Authors: Li Peng , Jiang Min , Liu Jin‐Tao 
Published: September 2014

AbstractThe asymmetric Pudovik reaction of chiral fluoroalkyl α,β‐unsaturated ketimines derivated from (R)‐tert‐butanesulfinamide and diphenyl phosphite was achieved in the presence of Rb2CO3 at room temperature. A series of fluoroalkylated α‐amino phosphonates were prepared in good yields with high diastereoselectivities.
A Novel Self‐Penetrated Framework with New Topology Based on Rigid Ligands
Authors: Lyu Guangxun , Chen Qihui , Jiang Feilong , Zhou Kang , Su Kongzhao , Chen Lian , Yuan Daqiang , Hong Maochun 
Published: September 2014

AbstractA novel coordination polymer, formulated as Zn6(TIB)4(BPTC)3(DMA)4(H2O)10 [TIB=1,3,5‐tris(1‐imidazolyl)‐benzene, H4BPTC=3,3′,5,5′‐biphenyltetracarboxylate], has been synthesized and structurally characterized. Further investigations reveal that it presents a new topology (topological symbol {62.84}{63}4{65.8}6{66}2) based on self‐penetration, and shows interesting fluorescent properties.
A Concise Synthesis of 2‐(2‐Hydroxyphenyl)acetonitriles via the o‐Quinone Methides Generated from 2‐(1‐Tosylalkyl)phenols
Authors: Wu Bo , Gao Xiang , Chen Mu‐Wang , Zhou Yong‐Gui 
Published: September 2014

AbstractA concise synthesis of 2‐(2‐hydroxyphenyl)acetonitriles has been developed through reaction of trimethylsilyl cyanide and the o‐quinone methides in situ generated from 2‐(1‐tosylalkyl)phenols under basic conditions. In addition, 2‐(2‐hydroxyphenyl)acetonitriles could be conveniently transformed to benzofuranones.
Noncardiac Surgery in Patients With Aortic Stenosis: A Contemporary Study on Outcomes in a Matched Sample From the Danish Health Care System
Authors: Andersson Charlotte , Jørgensen Mads Emil , Martinsson Andreas , Hansen Peter Wæde , Gustav Smith J. , Jensen Per Føge , Gislason Gunnar H. , Køber Lars , Torp‐Pedersen Christian 
Published: September 2014

ABSTRACTBackgroundPast research has identified aortic stenosis (AS) as a major risk factor for adverse outcomes in noncardiac surgery; however, more contemporary studies have questioned the grave prognosis. To further our understanding of this, the risks of a 30‐day major adverse cardiovascular event (MACE) and all‐cause mortality were investigated in a contemporary Danish cohort.HypothesisAS is not an independent risk factor for adverse outcomes in noncardiac surgery.MethodsAll patients with and without diagnosed AS who underwent noncardiac surgery in 2005 to 2011 were identified through nationwide administrative registers. AS patients (n = 2823; mean age, 75.5 years, 53% female) were matched with patients without AS (n = 2823) on propensity score for AS and surgery type.ResultsIn elective surgery, MACE (ie, nonfatal myocardial infarction, ischemic stroke, or cardiovascular death) occurred in 66/1772 (3.7%) of patients with AS and 52/1772 (2.9%) of controls (P = 0.19), whereas mortality occurred in 67/1772 (3.8%) AS patients and 51/1772 (2.9%) controls (P = 0.13). In emergency surgery, 163/1051 (15.5%) AS patients and 120/1051 (11.4%) controls had a MACE (P = 0.006), whereas 225/1051 (21.4%) vs 179/1051 (17.0%) AS patients and controls died, respectively (P = 0.01). Event rates were higher for those with symptoms (defined as use of nitrates, congestive heart failure, or use of loop diuretics), compared with those without symptoms (P < 0.0001).ConclusionsAS is associated with high perioperative rates of MACE and mortality, but perhaps prognosis is, in practice, not much worse for patients with AS than for matched controls. Symptomatic patients and patients undergoing emergency surgery are at considerable risks of a MACE and mortality.
Cancers associated with BRCA1 and BRCA2 mutations other than breast and ovarian
Authors: Mersch Jacqueline , Jackson Michelle A. , Park Minjeong , Nebgen Denise , Peterson Susan K. , Singletary Claire , Arun Banu K. , Litton Jennifer K. 
Published: September 2014

BACKGROUNDPrevious studies have reported additional cancers associated with BRCA mutations; however, the type, magnitude of risk, and sex differences remain to be clarified. The purpose of this study was to evaluate the incidence of cancers other than breast and ovarian cancer in known mutation carriers.METHODSAn institutional review board–approved study identified 1072 patients who had genetic counseling at the authors' institution and tested positive for a deleterious BRCA mutation. The expected number of cancer cases was calculated from the number of individuals in the study sample multiplied by the cancer incidence rates for the general population. The expected and observed numbers of cases were calculated in 5‐year intervals to accommodate different age‐related incidence rates. Standardized incidence ratios (SIRs) for each cancer type were calculated.RESULTSAmong the 1072 mutation carriers, 1177 cancers of 30 different cancer types were identified. Individuals with a BRCA1 mutation did not have a significant increase in cancers other than breast and ovarian cancer; however, a trend in melanoma was observed. Individuals with a BRCA2 mutation had significantly higher numbers of observed cases versus expected cases for pancreatic cancer in both men and women (SIR, 21.7; 95% confidence interval [CI], 13.1‐34.0; P < .001) and for prostate cancer in men (SIR, 4.9; 95% CI, 2.0‐10.1; P = .002).CONCLUSIONSThe results of this study uphold the current recommendations for hereditary breast and ovarian cancer screening of cancers other than breast and ovarian cancer by the National Comprehensive Cancer Network. Larger cohorts and collaborations are needed to further verify these findings. Cancer 2015;121:269–75. © 2014 American Cancer Society.
Real‐time Simulations of Photoinduced Coherent Charge Transfer and Proton‐Coupled Electron Transfer
Authors: Eisenmayer Thomas J. , Buda Francesco 
Published: September 2014

AbstractPhotoinduced electron transfer (ET) and proton‐coupled electron transfer (PCET) are fundamental processes in natural phenomena, most noticeably in photosynthesis. Time‐resolved spectroscopic evidence of coherent oscillatory behavior associated with these processes has been reported both in complex biological environments, as well as in biomimetic models for artificial photosynthesis. Here, we consider a few biomimetic models to investigate these processes in real‐time simulations based on ab initio molecular dynamics and Ehrenfest dynamics. This allows for a detailed analysis on how photon‐to‐charge conversion is promoted by a coupling of the electronic excitation with specific vibrational modes and with proton displacements. The ET process shows a characteristic coherence that is linked to the nuclear motion at the interface between donor and acceptor. We also show real‐time evidence of PCET in a benzimidazole–phenol redox relay.
In Situ Synthesised Silver Nanoparticle‐Infused L‐Lysine‐Based Injectable Hydrogel: Development of a Biocompatible, Antibacterial, Soft Nanocomposite
Authors: Mandal Subhra Kanti , Brahmachari Sayanti , Das Prasanta Kumar 
Published: September 2014

AbstractThe synthesis of L‐lysine‐based amphiphilic hydrogelator consisting of a naphthalene moiety at the N termini and an ethyleneoxy unit with free primary amine at the C terminus is reported. The amphiphile showed good gelation ability with minimum gelation concentration 0.6 % w/v in binary mixtures of dimethyl sulfoxide/phosphate buffer (1:4 v/v, pH 7.4). The hydrogel was characterised by spectroscopic and microscopic studies to delineate the role of non‐covalent interactions in self‐assembly gelation. Subsequently, Ag nanoparticles were synthesised within the hydrogel by in situ photo‐reduction of AgNO3 under sunlight, in which the gelators act as reducing/stabilising agents. The nanocomposites were characterised by transmission electron microscopy, UV/Vis and X‐ray diffraction spectroscopy and thermogravimetric analysis. Rheology of the soft nanocomposite showed significant mechanical strength and thixotropic self‐recovery properties, which made the composite suitable for use as a syringe‐injectable hydrogel. These soft nanocomposites exhibited excellent antibacterial activity against both Gram‐positive and Gram‐negative bacteria. They showed low haemolytic activity and high biocompatibility to mammalian (Chinese hamster ovarian) cells. In addition, agar–gelatin film infused with these nanocomposites allowed normal growth of mammalian cells on its surface while being lethal towards bacteria.
Two‐Step Directional Surface Modification of Iron Oxide Nanoparticles with Protected Siloxanes
Authors: Bloemen Maarten , Sutens Ben , Brullot Ward , Gils Ann , Geukens Nick , Verbiest Thierry 
Published: September 2014

AbstractSuccessful surface modification of iron oxide nanoparticles is crucial for their usage in applications. However, ligand exchange methods introducing siloxanes have several drawbacks. Presented here is a novel approach for the surface modification of iron oxide nanoparticles by making use of siloxanes, synthesized by thiol‐ene click chemistry, with protected functional groups. Afterwards the ligands are deprotected to liberate their functionality. This approach solves the issues related to ligand orientation and colloidal stability during surface modification.
Design and optimization of a 3‐coil resonance‐based wireless power transfer system for biomedical implants
Authors: Yi Ying , Buttner Ulrich , Fan Yiqiang , Foulds Ian G. 
Published: September 2014

SummaryThis paper presents a resonance‐based wireless power transfer system using a single layer of inductor coil windings, in a pancake configuration, in order to obtain a compact system for implantable electronic applications. We theoretically analyzed the system and characterized it by measuring its inductance, self‐resonant frequency, and quality factor Q. In our resonance‐based wireless power transfer prototype, we proposed a 3‐coil system, using two 15‐mm radius implantable coils, with a resonance frequency of 6.76 MHz. This system can effectively transfer power for a distance of up to 50 mm. Moreover, our proposed 3‐coil system can achieve a high Q‐factor and has a comparable power transfer efficiency (PTE) to previously reported works about 3‐coil and 4‐coil systems. The experimental PTE can achieve 82.4% at a separation distance of 20 mm and more than 10% PTE at a distance of 40 mm. Copyright © 2014 John Wiley & Sons, Ltd.
New aromatic amine based on cardanol giving new biobased epoxy networks with cardanol
Authors: Darroman Emilie , Bonnot Léa , Auvergne Remi , Boutevin Bernard , Caillol Sylvain 
Published: September 2014

Cardanol, derived from cashew nut shell liquid, was functionalized by thiol‐ene coupling with cysteamine to yield a new biobased aromatic amine. This cardanol amine was compared to the commercial cardanol‐based phenalkamines. These amines were characterized by NMR spectrometry and used as epoxy hardeners. The formulations of these amines with epoxidized cardanol in stoichiometric ratio were characterized by differential scanning calorimetry (DSC), thermogravimetry (TGA), dynamic mechanical (DMA) analyses and exhibit interesting properties for coating applications.Practical applications: The products of the chemistry described in this contribution, i.e., aromatic polyamine from cardanol and cysteamine hydrochloride, provide biobased building blocks for further epoxy resin syntheses by reaction with epoxy groups. The obtained epoxy resins are partially biobased and may be applied as binders and coatings.Biobased aromatic polyamine was synthesized by thiol‐ene coupling with cysteamine on cardanol, coming from cashew nut shell liquid (CNSL). Cardanol‐derived amine was used as hardener in biobased epoxy networks. Mechanical and thermal properties of obtained materials showed that cardanol‐derived amine material could lead to binders for composite application.
Tandem α‐Alkylation/Asymmetric Transfer Hydrogenation of Acetophenones with Primary Alcohols
Authors: Kovalenko Oleksandr O. , Lundberg Helena , Hübner Dennis , Adolfsson Hans 
Published: September 2014

AbstractA tandem α‐alkylation/asymmetric transfer hydrogenation of acetophenones with primary alcohols, mediated by a single ruthenium catalyst, is described. Under optimized reaction conditions and with use of [Ru(p‐cymene)Cl2]2in combination with an amino acid hydroxyamide ligand, the chiral secondary alcohol products were isolated in moderate yields and in moderate to good enantiomeric excess (up to 89 %ee).
Electrosensing Platform for Varenicline Based on Reduced Graphene Oxide
Authors: Teradal Nagappa L. , Narayan Prashanth S , Seetharamappa Jaldappagari , Satpati Ashis K. 
Published: September 2014

AbstractGraphene oxide (GO) was synthesized and reduced by chemical, hydrothermal and electrochemical methods. The GO and reduced GO was characterized by XRD, FTIR, absorption, Raman, FESEM and AFM methods. Chemically reduced GO (CrGO) was observed to efficiently enhance the electron transfer kinetics of varenicline compared to hydrothermally and electrochemically reduced GO. Hence, CrGO was used for the fabrication of an electrochemical sensor for the determination of varenicline in the concentration range of 0.03–50 µM with a limit of detection of 7.03 nM. The applicability of the proposed sensor was demonstrated by analyzing the biological samples containing varenicline.
Dynamic Structures of DNA Heptamers with Different Central Trinucleotide Sequences Studied by Electrochemical and Spectral Methods
Authors: Pilarova Iveta , Kejnovska Iva , Vorlickova Michaela , Trnkova Libuse 
Published: September 2014

AbstractA short, single‐stranded DNA fragment d(GCGAAGC) and its analogs d(GCNNNGC) carrying different trinucleotide sequences in the center of the molecule (AAA,CCC, GGG or TTT) were investigated by spectral (CD and UV spectra) and electrochemical methods (voltammetry, polyacrylamide gel electrophoresis). Our results show that (i) the central triplet GAA or AAA dramatically stabilizes DNA hairpins, (ii) a stem‐loop configuration is not supported by CCC or TTT sequences, instead, these heptamers adopt bimolecular duplex forms. Finally (iii), in the case of GGG sequence a very stable supramolecular G‐quadruplex is formed.
Electrochemistry of Methyl Viologen and Anthraquinonedisulfonate at Diamond and Diamond Powder Electrodes: The Influence of Surface Chemistry
Authors: Shpilevaya Inga , Foord John S. 
Published: September 2014

AbstractThe electrochemical behaviour of methyl viologen and anthraquinonedisulfonate was studied at electrodes produced from differing forms of diamond, including microcrystalline boron doped diamond, boron doped diamond powder and detonation nanodiamond powder. Two types of electrode pretreatment were employed to produce two dissimilar surface terminations: hydrophobic H‐terminated and hydrophilic O‐terminated. In the case of methyl viologen, it was found that the reduced neutral molecule adsorbed on all three electrodes if they were hydrogen terminated, but not if they were oxygen terminated. For anthraquinonedisulfonate, no adsorption was found on the solid diamond electrode, although again significant adsorption was noted on the powder electrodes, provided they were hydrogen terminated. The reasons underlying these observations are discussed in terms of hydrophobic and electrostatic interactions and the electrode morphology. The work provides information into the likely occurrence of adsorption and concomitant electrode fouling, which may be experienced in electroanalytical applications using solid and powdered forms of diamond.