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The structural properties and activities of Cu-Co catalysts used in Fischer-Tropsch synthesis are explored according to their method of preparation. Impregnation, co-precipitation, and a novel method of thermal decomposition were applied to an inorganic precursor complex to generate the Cu-promoted alumina- and silica-supported cobalt catalysts. The precursors and the catalysts obtained by their calcination underwent powder x-ray diffraction, thermal gravimetric analysis, specific surface area measurement using the Brunauer-Emmett-Teller method, scanning electron microscopy, and Fourier Transform InfraRed (FT-IR) spectroscopy. The catalytic performance of all calcined catalysts used in Fischer-Tropsch synthesis was investigated at 280 to 360 °C. The Cu-Co/SiO2 catalyst was prepared by thermal decomposition of [Cu(H2O)6][Co(dipic)2].2H2O/SiO2, which served as an optimal precursor for synthesis gas conversion into light olefins. The results highlight the advantages of this novel procedure over impregnation and co-precipitation approaches for effective and durable preparation of cobalt catalysts for Fischer-Tropsch synthesis.

Identification of microRNAs from plants is a crucial step for understanding the mechanisms of pathways and regulation of genes. A number of tools have been developed for the detection of microRNAs from small RNA-seq data. However, there is a lack of pipeline for detection of miRNA from EST dataset even when a huge resource is publicly available and the method is known. Here we present miRDetect, a python implementation to detect novel miRNA precursors from plant EST data using homology and machine learning approach. 10-fold cross validation was applied to choose best classifier based on ROC, accuracy, MCC and F1-scores using 112 features. miRDetect achieved a classification accuracy of 93.35% on a Random Forest classifier and outperformed other precursor detection tools in terms of performance. The miRDetect pipeline aids in identifying novel plant precursors using a mixed approach and will be helpful to researchers with less informatics background. • Automated pipeline to screen novel miRNA precursors from EST datasets of plants. • Mixed approach of homology and Random and forest classification. • Efficient classification with 93.35% accuracy. [ABSTRACT FROM AUTHOR]

The effect of the preparation method on the structural properties and activity of Ni-Co catalysts in the Fischer-Tropsch synthesis has been explored. Impregnation, co-precipitation and a novel method, thermal decompositions of inorganic precursor complex, procedures were applied for the generation of the Ni-promoted alumina- or silica-supported cobalt catalysts. The precursors and the catalysts that were obtained from their calcination were characterized by powder X-ray diffraction, thermal gravimetric analysis, Brunauer-Emmett-Teller specific surface area measurements, scanning electron microscopy and Fourier transform infrared spectroscopy. The catalytic performance in Fischer-Tropsch synthesis was investigated for all calcined catalysts in the temperature interval from 280 to 360 °C. The Ni-Co/AlO catalyst prepared by thermal decomposition of [Ni(HO)][Co(dipic)]·2HO/AlO as a precursor performed optimally for the conversion of synthesis gas to light olefins. The outcomes revealed that this novel procedure is more advantageous than impregnation and co-precipitation methods for the preparation of effective and durable cobalt catalysts for Fischer-Tropsch synthesis. [ABSTRACT FROM AUTHOR]

The influence of three preparation methods on the properties and reaction performances of a titania-supported Mn–Cr bimetallic nanocatalyst for high-temperature water–gas shift reaction has been studied. Impregnation, co-precipitation and thermal decomposition of the [Mn(H 2 O) 6 ] 3 [Cr(NCS) 6 ] 2 ·H 2 O/TiO 2 precursor as an inorganic precursor complex were utilized for the preparation of the Mn–Cr/TiO 2 catalysts. The calcined catalyst and the precursor that were used for its preparation were characterized by powder X-ray diffraction, scanning electron microscopy, Brunauer–Emmett–Teller specific surface area measurements, thermal gravimetric analysis, differential scanning calorimetry and Fourier transform–infrared spectroscopy. The high-temperature water–gas shift activity was appraised in the temperature range from 280 to 420 °C. The results showed that thermal decomposition of inorganic precursor complexes is more advantageous than impregnation and co-precipitation methods for the preparation of Mn–Cr/TiO 2 catalysts for high-temperature water–gas shift reaction. [ABSTRACT FROM AUTHOR]

Abstract: Silica-supported copper–nickel bimetallic catalyst was prepared from [Cu(H2O)6][Ni(dipic)2].2H2O/SiO2 precursor. The cationic–anionic complex, [Cu(H2O)6][Ni(dipic)2].2H2O, was prepared from the reaction of (NH4)2[Ni(dipic)2] with Cu(NO3)2.3H2O in water and characterized by elemental analysis, conductometric and various spectroscopy techniques such as FT-IR, UV–vis and atomic absorption. The physicochemical characteristics of both precursor and calcined catalyst were carried out using X-ray diffraction, thermal analysis methods (TGA and DSC), FT-infrared, scanning electron microscopy and BET specific surface area. The catalyst was evaluated for water gas shift reaction. When the Cu–Ni/SiO2 catalyst was used for water gas shift reaction at 300°C and atmospheric pressure, the CO conversion and CO2 selectivity were about 97.83% and 98.67%, respectively, showing higher activity and selectivity than the reference catalyst prepared by impregnation conventional method. [Copyright &y& Elsevier]

Abstract: Silica-supported Zn–Ni catalyst prepared by thermal decomposition of [Zn(H2O)6]2[Ni(NCS)6]·H2O/SiO2 precursor was tested in the water gas shift reaction. The characterization of both precursor and calcined catalyst was carried out using powder X-ray diffraction (XRD), FT-infrared, scanning electron microscopy (SEM), BET specific surface area and thermal analysis methods (TGA and DSC). The water gas shift reaction was studied over prepared catalyst in the temperature range of 280–420°C, gas hourly space velocity (GHSV) of 3600h−1 and H2O/CO molar ratio of 4 at atmospheric pressure. The Zn–Ni/SiO2 catalyst presented higher activity than the reference catalysts prepared by impregnation and co-precipitation methods. [Copyright &y& Elsevier]