Direct‐methanol Fuel Cell Based on Functionalized Graphene Oxide with Mono‐metallic and Bi‐metallic Nanoparticles: Electrochemical Performances of Nanomaterials for Methanol Oxidation

The catalysts based on 2‐aminoethanethiol functionalized graphene oxide (AETGO) with several mono‐metallic and bi‐metallic nanoparticles such as rod gold (rAuNPs), rod silver (rAgNPs), rod gold‐platinum (rAu‐Pt NPs) and rod silver‐platinum (rAg‐Pt NPs) were synthesized. The successful synthesis of nanomaterials was confirmed by various methods. The effective surface area (ESA) of the rAu‐Pt NPs/AETGO is 1.44, 1.64 and 2.40 times higher than those of rAg‐Pt NPs/AETGO, rAuNPs/AETGO and rAgNPs/AETGO, respectively, under the same amount of Pt. The rAu‐Pt NPs/AETGO exhibited a higher peak current for methanol oxidation than those of comparable rAg‐Pt NPs/AETGO under the same amount of Pt loading.     

Synthesis and characterization of novel phosphoramidates containing benzimidazole moiety

Novel heterocyclic phosphoramidates were synthesized by a nucleophilic substitution reaction of 2-substitutedbenzimidazoles and diphenyl chlorophosphate (ClPO₃Ph₂) in the presence of potassium hydroxide (KOH) under an argon atmosphere. The structures of the phosphoramidates were characterized by NMR, IR, melting point, and elemental analysis.     

Tungsten‐loaded SMP foam nanocomposites with inherent radiopacity and tunable thermo‐mechanical properties

Shape memory polymer (SMP) foams have been developed for use in neurovascular occlusion applications. These materials are predominantly polyurethanes that are known for their biocompatibility and tunable properties. However, these polymers inherently lack X‐ray visibility, which is a significant challenge for their use as implantable materials. Herein, low density, highly porous shape memory polyurethane foams were developed with tungsten nanoparticles dispersed into the foam matrix, at increasing concentrations, to serve as a radiopaque agent. Utilizing X‐ray fluoroscopy sufficient visibility of the foams at small geometries was observed. Thermal characterization of the foams indicated altered thermal response and delayed foam actuation with increasing nanoparticle loading (because of restricted network mobility). Mechanical testing indicated decreased toughness and strength for higher loading because of disruption of the SMP matrix. Overall, filler addition imparted x‐ray visibility to the SMP foams and allowed for tuned control of the transition temperature and actuation kinetics for the material. Copyright © 2015 John Wiley & Sons, Ltd.     

Synthesis of Two Natural Furan‐Cyclized Diarylheptanoids via 2‐Furaldehyde

Two natural diarylheptanoids, 2‐benzyl‐5‐(2‐phenylethyl)furan ( 1 ) and 2‐methoxy‐4‐{[5‐(2‐phenylethyl)furan‐2‐yl]methyl}phenol ( 2 ), were synthesized starting from 2‐furaldehyde. A Wittig reaction of 2‐furaldehyde with benzyltriphenylphosphonium bromide followed by reduction of the alkene C?C bond with Mg gave 2‐(2‐phenylethyl)furan ( 5 ). Lithiation of 5 with BuLi at ?78° followed by alkylation with benzyl bromide gave natural product 1 . In another approach, Friedel? Crafts acylation of compound 5 with benzoyl chloride followed by deoxygenation of the C?O group afforded 1 . The natural product 2 was also synthesized by acylation of 5 with 4‐acetoxy‐3‐methoxybenzoyl chloride ( 16 ) followed by deoxygenation and deacetylation.     

Photodynamic Inactivation of <Emphasis Type="BoldItalic">E. coli</Emphasis> PTCC 1276 Using Light Emitting Diodes: Application of Rose Bengal and Methylene Blue as Two Simple Models

The lack of a comparative study about potential of high-power light emitting diodes (LEDs) for photodynamic inactivation (PDI) of pathogenic microorganisms has remained as a challenging issue for researchers. Therefore, the aim of this study is to fill this gap through introduction of an efficient model for in vitro PDI in an aqueous medium. For this purpose, two individual 30 mW/cm² irradiation systems were designed using suitable sets of green and red LEDs. At another work, Methylene blue (MB) and Rose bengal (RB) as two simple models in the range of 5–150 μM were used in order to compare PDI of E. coli PTCC 1276 using red and green LED systems. Our results showed that a first-order mathematical model has the strength to describe the temporal variation of survival curves. Based on our results, when concentration of photosensitizer increased, the rate of inactivation for RB increased while MB depicted a maximum rate value at 25 μM. In a comparative study, optimum inactivation of E. coli PTCC 1276 obtained during 2- and 10-min irradiation of the LED systems using RB and MB at 150 and 25 μM, respectively. With regard to lower value of inactivation time and higher rate of inactivation for RB, use of simultaneous green high-power LEDs and RB is proposed as an efficient approach for PDI of pathogenic bacteria in future industrial applications.     

Fabrication of inorganic alumina particles at nanoscale by a pulsed laser ablation technique in liquid and exploring their protein binding,anticancer and antipathogenic activities

The interaction of nanoparticles with biological systems can provide useful information about their therapeutic applications. The aluminum nanoparticles (Al₂O₃ NPs) were synthesized by laser ablation technique and well-characterized by different methods. Fluorescence spectroscopy, circular dichroism (CD) spectroscopy, and molecular docking studies were employed to evaluate the effect of Al₂O₃ NPs on the protein structure. Growth inhibitory and apoptotic effects of the Al₂O₃ NPs against K562 cancer cells and lymphocyte cells were assessed using [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT), flow cytometry, and real time polymerase chain reaction (PCR) assays. The antipathogenic activity of Al₂O₃ NPs against a diverse range of Gram-negative and Gram-positive pathogens was explored through a disk diffusion method. The characterization techniques determined that the Al₂O₃ NPs were successfully synthesized in the nanoscales. Intrinsic, 1-anilino-8-naphthalenesulfonate (ANS) and acrylamide fluorescence spectroscopy studies disclosed that Al₂O₃ NPs can partially change the tertiary structure of human serum albumin (HSA), whereas CD spectroscopy investigation depicted that the secondary structure of HSA remained intact. Molecular docking investigation also manifest that the Al₂O₃ nano-clusters preferably bind to electrostatic residues. Al₂O₃ NPs exhibited promising and selective anticancer features through reactive oxygen species (ROS) production, apoptosis induction, and elevation of Bax/Bcl-2 mRNA ratio. Furthermore, the Al₂O₃ NP showed a remarkable antibacterial activity against both Gram-negative and Gram-positive pathogens. In conclusion, it may be suggested that the synthesized Al₂O₃ NPs can be integrated in the development of anticancer and antipathogenic agents.     

Fast determination of anthocyanins and free pelargonidin in fruits,fruit juices,and fruit wines by high‐performance liquid chromatography using a core–shell column

Anthocyanins are water‐soluble pigments that are liable for colors ranging from red to blue of most fruits, vegetables, and flowers. A novel and fast method was developed for the determination of five anthocyanins and free pelargonidin by high‐performance liquid chromatography coupled to photodiode array detection. A 10% formic acid and acetonitrile mixture was employed as mobile phase in the gradient elution mode. Mobile phase composition, column temperature, flow rate, injection volume, and column conditioning time were optimized by employing a stepwise strategy. Using a C₁₈ core–shell column (100 × 4.6 mm, 2.7 μm), the separation of six analytes was accomplished in less than 9.5 min with a run‐to‐run analysis time of 19 min. The developed method was validated with respect to linearity (r > 0.9999), limit of detection, limit of quantification, intra‐/interday precision (<2%), accuracy (98.6–104.4%), and specificity. Afterwards, the method was applied to the determination of anthocyanins present in 15 different samples including fruits, fruit juices, and fruit wines.     

Crystal structure of (<Emphasis Type="Italic">E</Emphasis>)-3-fluoro-N-((5-nitrothiophen-2-yl)methylene)aniline

The structure of the title compound C₁₁H₇FN₂O₂S was characterized by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P2₁/n with Z = 12, i.e. with three molecules in asymmetric unit. The molecules are not planar: the dihedral angles between the planes of thiophene and the benzene rings are 42.3(3)°, 42.0(3)°, and 48.9(2)°. In the crystal, intermolecular C–H···F interactions link the molecules through R₂² (14) ring motif. The crystal packing is also stabilized by π···π interactions.     

Weak sharp solutions for generalized variational inequalities

We consider weak sharp solutions for the generalized variational inequality problem, in which the underlying mapping is set-valued, and not necessarily monotone. We extend the concept of weak sharpness to this more general framework, and establish some of its characterizations. We establish connections between weak sharpness and (1) gap functions for variational inequalities, and (2) global error bound. When the solution set is weak sharp, we prove finite convergence of the sequence generated by an arbitrary algorithm, for the monotone set-valued case, as well as for the case in which the underlying set-valued map is either Lipschitz continuous in the set-valued sense, for infinite dimensional spaces, or inner-semicontinuous when the space is finite dimensional.     

On some λ difference sequence spaces of fractional order

In the present paper, the difference sequence spaces $c{s}_0^{\lambda }\left(\Delta \right),c{s}^{\lambda }\left(\Delta \right)$ and bs^λ(Δ) of nonabsolute type are generalized by introducing a generalized Λ difference operator $\Lambda \left({\Delta }^{\left(\stackrel{?}{\alpha }\right)}\right)$. Also, their Schauder basis are calculated and α-, β- and γ-duals of these spaces are investigated. Finally, some matrix transformations between these spaces and the basic sequence spaces ?_p, c and c₀ are characterized, where 1 ≤ p ≤ ∞.