Magnetic Nanoparticle-Supported Cu–NHC Complex as an Efficient and Recoverable Catalyst for Nitrile Hydration

Magnetic nanoparticles supported N-heterocyclic carbene–Cu complex was prepared and authenticated by FT-IR, SEM, EDX, VSM, powder-XRD. The catalytic activity of these magnetically retrievable NPs was investigated for hydration of nitriles as the simplest route for the synthesis of amides in an atom-economical manner. A wide range of nitriles containing various functional groups such as olefin, aldehyde, nitro, carboxylic acid was examined in this transformation to generate their corresponding amides in the aqueous medium. The immobilized catalyst was easily recovered using an external magnet and reused for six times without significant loss of its catalytic activity.

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Synthesis and characterization of conductive neural tissue engineering scaffolds based on urethane-polycaprolactone

Polymeric biomaterials play a key role in enhancement of lengthy nerve regeneration and various types of scaffolds were used to pave the way for nerve regeneration. Electrospun fibrous scaffolds have special potential applicability in controlling the cell behaviors such as adhesion, growth, proliferation and function. This study attempted to design a conductive and porous fibrous scaffold containing polycaprolactone (PCL) and polyaniline (PANI) with controllable degradation rate by adding urethane groups in scaffold structures. FTIR and NMR analysis was used to characterize the chemical bonds. Morphology, porosity, conductivity and degradation rate of scaffolds were also evaluated. To assess the cell–scaffold interaction, PC-12 cell line was cultured on the scaffolds. Results showed that the degradation rate of composite samples significantly increased in 50 time period. It seems that these results suggest that the composite fibrous scaffolds having proportions of UPCL/PCL/PANI45:20:35 exhibit the most balanced properties that meet all of the required specifications for neural cells and possess a potential application in neural tissue engineering.     

Photoluminescence and UV photosensitivity of few-layered MoS2 nanosheets synthesized under different hydrothermal growth times

Journal of Materials Science - MoS2 flower-like microspheres composed of 2D nanosheets were prepared using the simple and cost-effective method of hydrothermal. The effects of hydrothermal process...     

The impacts of tomato residuum extract with Arabic gum and dill essential oil on the shelf life improvement of trout fillets stored at chilly condition

The objective of this study was to evaluate the effects of tomato residuum extract (TRE) dipping and Arabic gum (AG) coating enriched with dill essential oil (DEO) on the shelf life extension of refrigerated trout fillets. Gas chromatography/mass spectrometry analysis revealed that the main constituents of DEO were alpha-phellandrene (30.17%), limonene (28.31%), and carvone (21.31%). Antioxidant activities of acetone, ethanol, methanol, cold, and hot water extracts of tomato residuum were examined using reducing power and 2,2-azinobis-3-ethylbenzothiazoline-6-sulphonic acid assays in maceration, ultrasound, and combined ultrasound and maceration extraction methods. The strongest antioxidant activities were found in the ultrasound-assisted extraction with ethanol 50%. Thiobarbituric acid, total volatile basic nitrogen, and peroxide values indicated that TRE 3%–AG–DEO 2% and TRE 6%–AG–DEO 2% treatments could significantly (p ≤ .05) extend the shelf life of the fillets. Also, sensory evaluation showed that TRE along with DEO had significant (p ≤ .05) pleasant effects on the sensory characteristics of the fillets. It was concluded that TRE dipping along with AG coating containing DEO could be a suitable alternative for the synthetic preservative in the refrigerated trout fillets.     

An efficient hybrid algorithm based on modified imperialist competitive algorithm and K-means for data clustering

Clustering techniques have received attention in many fields of study such as engineering, medicine, biology and data mining. The aim of clustering is to collect data points. The K-means algorithm is one of the most common techniques used for clustering. However, the results of K-means depend on the initial state and converge to local optima. In order to overcome local optima obstacles, a lot of studies have been done in clustering. This paper presents an efficient hybrid evolutionary optimization algorithm based on combining Modify Imperialist Competitive Algorithm (MICA) and K-means (K), which is called K-MICA, for optimum clustering N objects into K clusters. The new Hybrid K-ICA algorithm is tested on several data sets and its performance is compared with those of MICA, ACO, PSO, Simulated Annealing (SA), Genetic Algorithm (GA), Tabu Search (TS), Honey Bee Mating Optimization (HBMO) and K-means. The simulation results show that the proposed evolutionary optimization algorithm is robust and suitable for handling data clustering.     

A dynamic data dissemination mechanism for Cassandra NoSQL data store

The Journal of Supercomputing - Cassandra as a type of NoSQL databases has been put forward so as to surmount the hurdles of traditional relational databases in the scope of big data as well as...     

An efficient synthesis of novel sulfonyl[3.3.3]heteropropellanes from sulfonylacetamidines and ninhydrin-malononitrile adduct

The synthesis in good yields of a novel class of sulfonyl[3.3.3]heteropropellanes via a one pot, five-component reaction between sodium arylsulfinates, trichloroacetonitrile, primary amines, and the malononitrile-ninhydrin adduct in H₂O at room temperature has been reported.