bluuebunny/crossref_metadata_2025_split huggingface dataset:
High Efficiency for Hydrogen Evolution and Bacterial Inactivation of Ag‐TiO2‐Graphene Ternary Nanocomposites with Appropriate Ag Ratios
Authors: Sheu Fu‐Jye , Cho Chun‐Pei 
Published: January 2018

AbstractAg‐TiO2‐graphene (ATG) ternary nanocomposites with various Ag contents were synthesized at fixed mixing ratios of TiO2 to graphene. The successful fabrication of them was confirmed by XRD, SEM, TEM, Raman and XPS spectra. The stronger Raman signals caused by the increased Ag content were considered as a significant evidence for the SPR effect. An increased Ag content gave rise to not only a wider absorption range but also a higher visible‐light absorbance. The results of electrochemical analysis illustrated that more Ag loading caused a reduced interfacial impedance, and improved conductivity and electron transport. However, excess Ag nanoparticles led to agglomeration and decreased surface area unfavorable to light absorption. Thus, an appropriate Ag content was required to achieve higher optical response and photocatalytic efficiency. It was found that for each fixed mixing ratio of TiO2 and graphene, there was a corresponding optimum Ag content. The hydrogen evolution results displayed the same trend as photodegradation, indicating again that the optimum ratio of TiO2 and graphene was 5: 1, and the extent of Ag loading was really crucial. By appropriate ratios of graphene and Ag, A15TG(5) exhibited the highest efficiency in both photodegradation and hydrogen evolution. Its QE and mass‐normalized hydrogen evolution rate were 26.2% and 705.6 μmol⋅g−1⋅h−1, respectively. Furthermore, the ATG nanocomposites also showed promising capability for bacterial inactivation.
Comparison of the Catalytic Activity of Copper Nanostructures in Friedel‐Crafts‐Type Condensation Reactions
Authors: Saiadian Shohreh , Khorshidi Alireza 
Published: January 2018

AbstractThe catalytic activity of copper nanostructures in the condensation reaction of selected indoles and aldehydes or ketones was investigated. Cu(acac)2, zeolite Y‐encapsulated Cu(acac)2, free and zeolite Y‐encapsulated CuO nanoparticles, and Cu2O nanoparticles with different size and shapes were prepared successfully and characterized by means of UV‐Vis spectroscopy, Fourier‐transform infrared spectroscopy (FTIR), diffuse reflectance spectroscopy (DRS), X‐Ray diffraction analysis (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive X‐Ray analysis (EDX). Cubic Cu2O nanoparticles showed superior activity as a heterogeneous catalyst compared to other catalytic systems. Excellent yields of the desired bis(indolyl)methanes were obtained via condensation reaction of indoles and aldehydes in presence of cubic Cu2O nanoparticles under mild reaction conditions and the catalyst retained activity for six successive catalytic runs.
Kinetics of CO2 Absorption into Aqueous AMP/HMDA/TEG Mixtures
Authors: Patil Mayurkumar P. , Vaidya Prakash D. 
Published: January 2018

AbstractMixtures of 2‐amino‐2‐methyl‐1‐propanol (AMP), 1,6‐hexamethyl diamine (HMDA), triethylene glycol (TEG) and water, which merge the loading capacity of AMP, reactivity of HMDA and low volatility of TEG, are improved CO2‐capturing solvents. In the present study, kinetic aspects of the reaction of CO2 with the blend AMP+HMDA were investigated using co‐solvents TEG+Water. Kinetic data were experimentally obtained in a stirred cell at 303–318 K. The concentrations of AMP and HMDA in the mixtures were changed in the 2–3 and 0.1‐0.5 M range whereas TEG concentration was changed between 0.7 and 2 M. Pseudo‐first order rate constants were measured. Knowing the CO2 absorption rates in the aforesaid mixtures, the second‐order rate constant (65195 M−1 s−1) for the reaction between CO2 and HMDA at 308 K was found. The activation energy for the CO2‐HMDA system in aqueous solution was 33.1 kJ/mol. Equilibrium solubility of CO2 in AMP/HMDA/TEG/Water mixtures was measured. Finally, it was established that N,N’‐dimethyl‐1,6‐hexamethyl diamine (or HMDA−N,N’) – a dialkyl derivative of HMDA – is a further attractive promoter for AMP in TEG+Water mixtures.
Dual‐Functional Templated Methodology for the Synthesis of Hierarchical Porous Carbon for Supercapacitor
Authors: Shen Feng , Qiu Mo , Hua Yinhan , Qi Xinhua 
Published: January 2018

AbstractDual‐functional templated methodology was developed for synthesis of hierarchical porous carbons via direct thermal decomposition of agricultural wastes, in which dairy manure acted as low cost carbon precursor and eggshell as both hard template and activating agent source of CO2. The dual‐functional template can be easily removed by diluted HCl instead of corrosive HF. Carbonization temperature and dosage of eggshell have great influence on the porous texture of the carbon materials. Optimized temperature of 800 oC and mass ratio of eggshell/dairy manure (2:1) facilitate the releasing of CO2 from eggshell thus benefitting the formation of hierarchical porous carbon. The porous carbon has maximum surface area of 543.6 m2/g and total pore volume of 0.48 cm3/g of which micropores account for 40%. As the electrode of supercapacitor, the obtained hierarchical porous carbons showed a relative high specific capacitance of 226.6 F/g in KOH aqueous electrolyte (6 mol/L). Besides, it exhibited outstanding cycling stability with almost 100% of specific capacitance retention after 2500 GCD cycles. The one‐step template carbonization method provides a facile and sustainable route to prepare hierarchical porous carbons from the agricultural wastes.
Recent Advances in Preparation of Porous Polymeric Membranes by Unique Techniques and Mitigation of Fouling through Surface Modification
Authors: Remanan Sanjay , Sharma Maya , Bose Suryasarathi , Das Narayan Ch. 
Published: January 2018

AbstractIn this review, modern techniques for the membrane preparation including 3D printing, phase separation micro molding, selective etching and self‐assembled and non‐solvent induced phase separation (SNIPS) are discussed. The article also takes account of traditional membrane preparation techniques such as phase inversion, sintering, track etching and electrospinning. Although, there is plenty of literature exists on the preparation and tailoring of membrane properties, there are still challenges to develop and establish a reliable membrane fabrication method with high flux, selectivity and anti‐fouling properties. Hydrophobic polymers are more prone to foul due to its low surface energy compared to hydrophilic polymers. Fouling resistance of membrane against microbes and proteins had been significantly improved by the use of nanoparticles, and modification with hydrophilic polymers. Mussel‐inspired coating and amyloid proteins are also recently found to have excellent antibacterial activity are also reviewed. Hence, a broad understanding of structure and properties is essential for further development and progress in membrane technology for water purification.
Synthesis, Biological Activity and Structure‐Activity Relationship of Novel Diphenylurea Derivatives Containing Tetrahydroquinoline as Carbonic Anhydrase I and II Inhibitors
Authors: Atahan Alparslan , Gencer Nahit , Bilen Cigdem , Yavuz Emre , Genc Hayriye , Sonmez Fatih , Zengin Mustafa , Ceylan Mustafa , Kucukislamoglu Mustafa 
Published: January 2018

AbstractA series of novel tetrahydroquinoline derivatives containing urea moiety was synthesized and their in vitro inhibitory effects on the human carbonic anhydrase isoenzymes (hCA−I and hCA‐II) were evaluated by using the CO2 hydration method. All the synthesized compounds exhibited inhibitory activity against both hCA I and hCA II with 1‐(4‐fluorophenyl)‐3‐(4‐(4‐p‐tolyl‐5,6,7,8‐tetrahydroquinolin‐2‐yl)phenyl)urea (7 k, IC50 value of 5.28 μM and 5.51 μM, against hCA I and hCA II, respectively) as the strongest inhibitor in this study. Structure‐activity relationships were also investigated. The results showed that most of synthesized compounds have a higher inhibitory activity against hCA I than hCA II. Also the substituents, containing two or more pairs of non‐bonding electrons, generally increased the hCA I and II inhibitory activity. Furthermore, some electronic parameters such as the highest occupied molecular orbital and the lowest unoccupied molecular orbital (HOMO‐LUMO) energy levels, electron affinity, total energy and dipole moments of the best inhibitors (7 b, 7 h and 7 k) in this study were also calculated by using Gaussian software. The results revealed that HOMO‐LUMO energy differences, total energy, chemical hardness and dipole moment of 7 b, 7 h and 7 k showed a linear relationship with increasing inhibitory activity.
Aggregation‐Induced Emission, Functionalized Fluorescent Nanoparticles and Cells Imaging of a Water‐Soluble Pyridyl‐Naphthalimide Dendron
Authors: Yao Shankun , Qian Ying 
Published: January 2018

AbstractThis paper reports on the design, synthesis and spectral characteristics of a novel pyridyl‐naphthalimide aggregation‐induced emission (AIE) dendron named PADN, and intermediate compound named PAN. PADN and PAN emitted brightly fluorescence in solid state and a maximum emission wavelength at 497 nm (green fluorescence) and 454 nm (blue fluorescence) in pure THF solution respectively. A considerable fluorescence intensity was found for PADN when water fraction reached a high value (the quantum yield of 90% water fraction was 0.15). Because of a stable core‐shell structure by the surface contains easily modified amino groups, the two AIE‐dendrons were successfully encapsulated in silica matrix, emitting bright green fluorescence with 0.33 quantum yield (PADN) and clear blue fluorescence with 0.27 quantum yield (PAN). Additionally, dye PADN was successfully applied for cell imaging, getting clear green‐field photograph, which indicated a better uptake by lung cancer cells A‐549 and suggested its promising application for biosensors.
Robust and Self‐Healing Hydrophobic Association Hydrogels Using Poly(styrene‐co‐acrylonitrile) Macromolecule Microspheres as Cross‐Linking Centers
Authors: Chen Jing , Zhang Yulin , Hu Chengxin , Deng Yingxue , Shi Linying , Ran Rong 
Published: January 2018

AbstractIn our strategy, polystyrene (PS) and poly(styrene‐acrylonitrile) (P(S‐AN)) macromolecular microspheres (MMs) were introduced within hydrophobically associated (HA) hydrogels to enhance their mechanical strength. Two series of MMs hydrophobically associated polyacrylamide composite hydrogels (MMHA gels) were fabricated by a simple one‐pot method. The mechanical, rheological and swelling properties of MMHA gels were investigated and also evaluated as a function of the content of MMs. The mechanical properties of MMHA gels exhibit a tendency to increase first and then decrease with the increase in MMs content. In addition, the structure of the MMHA hydrogels was investigated by the IR and SEM analysis. The results were consistent with the result of mechanical, self‐healing and swelling properties test. Impressively, compared with MMHA gels enhanced by PS MMs (SHA gels), MMHA gels enhanced by P(S‐AN) MMs (SNHA gels) showed better mechanical properties(tensile strength 550 KPa, elongation at break 2832%)due to the strong dipole‐dipole interactions of ‐CN groups from acrylonitrile. Furthermore, the oil/water separation capability of the SNHA gels was explored preliminarily. Our strategy shows a novel direction for the production of tough hydrogels with various potential applications.
Straightforward Synthesis of Isoellipticine by Palladium‐Catalysed Coupling Reactions
Authors: Naciuk Fabrício F. , Castro Joaquim A. M. , Serikava Bruno K. , Miranda Paulo C. M. L. 
Published: January 2018

AbstractOur novel synthetic route to isoellipticine featured palladium‐catalyzed intramolecular reactions for the construction of the B ring of the pyridocarbazole nucleus. The adequate palladium‐catalyzed reaction depended upon the oxidation conditions that were applied in order to prepare the immediate synthetic precursor. When CAN was used to make the quinone intermediate, an oxidative cyclization through a double C−H bond activation was applied. Conversely, when the oxidation condition involved TCCA as oxidant, a direct C−H arylation was employed. Both approaches showed similar efficiencies in order to construct the pyridocarbazole nucleus. Isoellipticine was prepared in only 5 steps with a 21%–23% overall yield.
MoS2‐TiO2 Nanocomposite with Excellent Adsorption Performance and High Antibacterial Activity
Authors: Pal Arnab , Jana Tushar K. , Roy Tamanna , Pradhan Ananya , Maiti Ramaprasad , Choudhury Sujata M. , Chatterjee Kuntal 
Published: January 2018

AbstractThe need of multifunctional advanced materials, facilitating clean and sustainable environment is the key issue from the perspective of materials scientists. This study demonstrates facile and scalable synthesis of MoS2‐TiO2 nanocomposites and their excellent performance as nanoadsorbents and antibacterial agent. The synthesized composites, with different loading of MoS2 and TiO2, were examined by XRD, XPS, RAMAN, FESEM and HRTEM for structural, chemical and morphological details. The MoS2‐TiO2 nanocomposite displays adsorption capacity as high as 364.56 mg g−1 for methylene blue (MB) at room temperature and the kinetic data reveal that the adsorption process of MB is well‐matched with the pseudo‐first‐order model. The MoS2‐TiO2 nanocomposites, with different morphology, have shown their capability as an organic dye scavenger with high speed and efficiency. Moreover the composites execute considerable antibacterial activity against Gram positive Staphylococcus aureus and Gram negative Escherichia coli bacteria. Thus the presented MoS2‐TiO2nanocomposite, with synergistic performance, shows huge potential in the search of multifunctional smart materials for future technology to address environment issues.
Fe3O4 Nanoparticles: A Robust and Magnetically Recoverable Catalyst for Direct C‐H Bond Selenylation and Sulfenylation of Benzothiazoles
Authors: Rafique Jamal , Saba Sumbal , Frizon Tiago E. A. , Braga Antonio L. 
Published: January 2018

AbstractHerein, we report the magnetically recoverable Fe3O4 nanoparticle‐catalyzed synthesis of 2‐organochalcogen‐benzothiazoles via direct C−H bond chalcogenation. This new approach works under an air atmosphere, affording the desired products in good to excellent yields using benzothiazoles, a half‐molar equiv. of various diorganyl dichalcogenides, and 10 mol % of catalytic loading. The method is attractive due to the recyclability of the catalyst and tolerance of a wide range of functional groups.
Synthesis and Photophysical Properties of C3‐Symmetric Star‐Shaped Molecules Containing Heterocycles: A New Tactics for Multiple Fischer Indolization
Authors: Kotha Sambasivarao , Todeti Saidulu , Das Tarasankar , Datta Anindya 
Published: January 2018

AbstractWe report synthesis of several C3‐symmetric molecules containing three indole units with benzene ring as a central core. Triple Fischer indolization has been accomplished under green conditions using low melting mixture of L‐(+)‐tartaric acid (TA) and N,N′‐dimethyl urea (DMU). In addition to Fischer indolization, another three popular reactions such as Friedel–Crafts acylation, Grignard reaction, and Suzuki–Miyaura cross‐coupling have been used as key steps to build C3‐symmetric star‐shaped molecules containing indole, furan, and thiophene moieties. Readily available inexpensive chemicals such as acetone, acetophenone, 4‐bromo acetophenone have been used as starting materials.
Use of Glycosyl Dithiocarbamates: Small Molecule ‘Turn‐on’ Fluorescent Probe for Carbohydrate Binding Proteins
Authors: Das Rituparna , Mishra Bedangshu , Mukhopadhyay Balaram 
Published: January 2018

AbstractA glycosyl dithiocarbamate derivative is developed as a “turn on” fluorescent sensor for lectins. The probe is prepared through a three‐component reaction in good yield and fully characterized by analytical experiments. Upon interaction with lectin ConA, the virtually non‐fluorescent probe has shown “turn on” sensing with absolute specificity in terms of the carbohydrate used, mannose in this particular case. The probe with galactose remained inactive with ConA. The simple and general strategy for the synthesis of this particular probe offers the scope for multiple probes by altering the carbohydrate moiety and thus, opens up the avenue to target various lectin sensing.
Enhancing the Oxidation Stability of Polydivinylbenzene Films via Residual Pendant Vinyl Passivation
Authors: Lepró Xavier , Ehrmann Paul , Rodríguez Jennifer , Baxamusa Salmaan 
Published: January 2018

AbstractPolydivinylbenzene (PDVB) is a thermally stable, optically transparent, crosslinked polymer that until recently has been difficult to synthesize as a thin film. With the recent demonstration of initiated chemical vapor deposition (iCVD) of thin PDVB films, a renewed interest in the material properties of PDVB has developed. In particular, attention is now focused on its oxidation pathways and long‐term stability under the desired application use conditions. Here, we report on the thermal and environmental stability of PDVB films and show that unreacted pendant vinyl groups drive polymer oxidation upon exposure to either air or light. We demonstrate that such vinyls can be effectively passivated by a simple ex‐situ thermal annealing at ca. 300 °C in inert atmosphere that induces an 87% reduction of the PDVB oxidation rate in air and slows light (λ=405 nm) induced oxidation by 56%. While the thermal annealing is less effective at preventing oxidation under higher energy (λ = 365 nm) UV light, we demonstrate that this aging pathway is based on the presence of reactive oxygen species rather than traditional photo‐oxidation. Vinyl removal through ex‐situ thermal annealing improves the chemical stability of iCVD PDVB to continuous air (over 500 days) or light (70 hours) exposure and offers a simple option to improve its environmental aging resistance which is important for long‐term protective applications.
Site‐Selective Hydrosilylation of Botryococcene ‐ The Algal Biomass Hydrocarbon Oil
Authors: Kawashima Hidehisa , Umezawa Mami , Kijima Masashi 
Published: January 2018

AbstractAn algal acyclic triterpene botryococcene ((E)‐2,3,7,10,13,16,20,21‐octamethyl‐6,17‐dimethylene‐10‐vinyldocosa‐1,11,21‐triene), new biomass for material sources, which has three‐types of six carbon‐carbon double bonds, i. e., four vinylidenes at C2,6,17,21‐positions, one C10‐vinyl, and one C11‐12 internal olefin, in the molecule underwent hydrosilylation of various organosilanes in the presence of Pt(0) 1,3‐divinyl‐1,1,3,3‐tetramethyldisiloxane complex (Karstedt's catalyst). Various hydrosilylated botryococcene derivatives were site‐ and regioselectively obtained in high yields by an anti‐Markovnikov type addition at the C10‐vinyl moiety without any isomerizations of the unsaturated triterpenoid skeleton.
Synthesis and Investigations of Chiral NNO Type Copper(II) Coordination Polymers
Authors: Larionov Vladimir A. , Yashkina Lidiya V. , Smol'yakov Alexander F. , Zubavichus Yan V. , Babievsky Kirill K. , Akat'yev Nikolay V. , Titov Aleksei A. , Belokon Yuri N. , Maleev Victor I. 
Published: January 2018

AbstractHerein, we report the synthesis and characterizations of chiral copper(II) coordination polymers (CPs) based on Schiff base of (S)‐2‐aminomethylpyrrolidine and salicylaldehyde derivatives. Single crystal X‐ray analysis showed that copper(II) complex is 1D CP, with the repeating units LCu‐OAc (L=ligand) organized in a perpendicular manner, where the copper(II) atoms are six‐coordinated and have a distorted octahedral geometry. Also complex with chlorine counter ion having unusual dimeric structure was synthesized and characterized. It was demonstrated that CPs catalyze the enantioselective Henry reaction with up to 78% ee.
Pd Nanoparticles Immobilized on Graphene Oxide/Silica Nanocomposite: Efficient and Recyclable Catalysts for Cross‐Coupling Reactions
Authors: Oliveira Rafael L. , Oliveira Cristine S. , Landers Richard , Correia Carlos R. D. 
Published: January 2018

AbstractPd nanoparticles were synthesized on non‐functionalized and functionalized graphene oxide with thiol and amine groups. The resulting materials were used as recyclable catalysts to study the influence of the functional groups and compare their activity and stability to non‐functionalized graphene oxide and commercial catalysts in the Heck and Suzuki reactions. The catalyst based on non‐functionalized GO and commercial catalysts lost their activity quickly because of particle growth (Oswald ripening). However, the presence of functional groups reduces significantly the metal particle growth producing more efficient catalysts for the Heck and the Suzuki reactions. Moreover, the synthesized catalysts were capable of catalyzing the Heck and Suzuki reactions using different substrates, achieving good activities and selectivities in all cases.
An Asymmetric Synthesis of ((3R,6R)‐6‐Methylpiperidine‐3‐yl)methanol; A Piperidine Core Unit of Potent Dual Orexin Receptor Antagonist MK‐6096
Authors: Kaur Amanpreet , Prakash Ranjana , Pandey Satyendra Kumar 
Published: January 2018

AbstractAn asymmetric synthesis of ((3R,6R)‐6‐methylpiperidin‐3‐yl)methanol 2, a potent dual orexin receptor antagonist MK‐6096 1 piperidine core unit, is described. The synthesis utilizes commercial available (S)‐propylene oxide as a starting material and organocatalyzed asymmetric Michael addition reaction as key step.
Zinc Oxide Based Composite Materials for Advanced Supercapacitors
Authors: Wang Yuyin , Xiao Xiao , Xue Huaiguo , Pang Huan 
Published: January 2018

AbstractZinc oxide based composite materials show advantages such as low cost, environmental protection, good electrochemical reversibility, high specific capacitance, high power density, high energy density, good cycling stability and simple preparation, which makes them promising materials for advanced supercapacitors. Based on the most advanced research, we present recent findings in the investigation, discussion and challenges related to various kinds of zinc oxide based composite materials, such as zinc oxide/carbon, zinc oxide/graphene, zinc oxide/manganese dioxide, zinc oxide/nickel oxide and other composites.
Synthesis, Biological Assessment and Molecular Modeling of Racemic QuinoPyranoTacrines for Alzheimer's Disease Therapy
Authors: Chioua Mourad , Serrano Estefanía , Dgachi Youssef , Martin Hélène , Jun Daniel , Janockova Jana , Sepsova Vendula , Soukup Ondrej , Moraleda Ignacio , Chabchoub Fakher , Ismaili Lhassane , Iriepa Isabel , Marco‐Contelles José 
Published: January 2018

AbstractIn this report we describe the synthesis, biological evaluation and molecular modeling of new tacrine analogues such as QuinoPyranTacrines (QPTs), designed by juxtaposition of 1,4‐naphthoquinone and tacrine. From these results we have identified QPT16 as a permeable, selective human acetylcholinesterase inhibitor [IC50= 1.1 ± 0.15 μM], 3.5‐fold less‐hepatotoxic than tacrine at 1000 μM concentration, and consequently, a potential new hit‐compound for further investigation targeted to find a new agent for AD therapy.
Co(II) or Cu(II) Schiff Base Complex Immobilized onto Carbon Nanotubes as a Synergistic Catalyst for the Oxygen Reduction Reaction
Authors: Bai Lu , Li Min , Guan Jingqi 
Published: January 2018

AbstractHeterogenization of molecular catalysts not only showed excellent activity and selectivity in many catalytic reactions, but also provided definite active sites feasible to explore the reaction mechanism. Herein, we report a heterogenization of metal Schiff‐base complex immobilized on multiwalled carbon nanotubes (MWCNTs) as a high‐performance catalyst for the oxygen reduction reaction (ORR). Although MWCNTs alone have little catalytic activity, the heterogenization hybrid exhibits an enhanced ORR activity in alkaline solutions. The enhanced catalytic activity arises from synergetic effects between metal Schiff‐base complexes and MWCNTs.