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To determine the effects of minerals inside char particles and bed materials, the process and mechanism of char combustion in a fluidized bed were studied using a Micro Fluidized Bed Reactor Analyzer. A demineralization procedure using HCl and HF was employed to remove the minerals from pyrolyzed char samples. Raman spectroscopy was used to study the carbon structure of the remaining solid char after demineralization at 500 °C, 600 °C, 700 °C and 800 °C. From the regular changes in band area ratio and full width at half maximum, it can be concluded that as pyrolysis temperature increases, the carbon structure becomes highly ordered, the plane lattice size gradually increases, and the reaction activity decreases from 0.245 s−1 to 0.138 s−1.Furthermore, minerals both within the char particle and in the external bed had marked catalytic activity on char combustion, and their combined catalysis was most notable. CaO and Fe 2 O 3 were the dominant active minerals components contributing to catalytic combustion of char in this study. The catalytic action of CaO was stronger than that of Fe 2 O 3. The activation energy of char combustion ranged from 57.70 kJ/mol to 91.53 kJ/mol, and it significantly decreased in the presence of the bed materials. • The contribution of the minerals in the char and the external material bed to the combustion of the char was studied. • The catalysis of oil shale ash in the external material bed is sometimes greater than the pyrolysis temperature. • CaO and Fe 2 O 3 have obvious catalytic activity. • CaO shows catalytic activity at both low and high temperature, whereas Fe 2 O 3 had strong activity only at low temperature. • The change of ordered carbon structure has a negative effect on the reaction rate of char combustion. • The catalytic mechanism of combustion is concluded. [ABSTRACT FROM AUTHOR]

Data mining in protein databases, derivatives from more fundamental protein 3D structure and sequence databases, has considerable unearthed potential for the discovery of sequence motif-structural motif-function relationships as the finding of the U-shape (Huf-Zinc) motif, originally a small student's project, exemplifies. The metal ion zinc is critically involved in universal biological processes, ranging from protein-DNA complexes and transcription regulation to enzymatic catalysis and metabolic pathways. Proteins have evolved a series of motifs to specifically recognize and bind zinc ions. Many of these, so called zinc fingers, are structurally independent globular domains with discontinuous binding motifs made up of residues mostly far apart in sequence. Through a systematic approach starting from the BRIX structure fragment database, we discovered that there exists another predictable subset of zinc-binding motifs that not only have a conserved continuous sequence pattern but also share a characteristic local conformation, despite being included in totally different overall folds. While this does not allow general prediction of all Zn binding motifs, a HMM-based web server, Huf-Zinc, is available for prediction of these novel, as well as conventional, zinc finger motifs in protein sequences. The Huf-Zinc webserver can be freely accessed through this URL (). [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Over physically mixed CuO-Pd/C furfural hydrogenation was performed with formic acid. • CuO firstly dissolved into Cu2+ by formic acid, then Cu2+ was reduced by the Pd-H. • Pd promoted the furfural conversion and Cu improved the furfuryl alcohol selectivity. • Cu-Pd alloys functioned well in this reaction with 98.1% furfuryl alcohol yield. • In-situ prepared Cu-Pd/C exhibited an excellent recycle stability. Abstract Catalytic transfer hydrogenation (CTH) of bio-derived furfural (FF) to furfuryl alcohol (FFA) was performed using the physically mixed CuO-Pd/C as catalyst and formic acid (FA) as hydrogen donor. The evolution investigation of Cu showed the precursor CuO firstly dissolved into Cu2+ by FA and then formed coordination polymer-copper(II), which uniformly dispersed in reaction solution of 1, 4-dioxane. Subsequently the Cu2+ was in-situ reduced and Cu-Pd alloys formed simultaneously. The in-situ prepared nano Cu-Pd/C catalyst exhibited the best performance with a complete FF conversion and FFA selectivity of 98.1%. Reaction conditions test suggested that the FFA selectivity was greatly dependent on the Cu content. The underlying mechanism revealed that the Pd in Cu-Pd alloys mainly promoted the FF conversion by enhancing hydrogen adsorption, while the nano Cu for increasing FFA selectivity; the Cu-Pd alloys functioned in synergistic way. Leaching and recycling tests demonstrated an excellent stability of the Cu-Pd/C catalyst. [ABSTRACT FROM AUTHOR]

An efficient iodine–DMSO catalyzed system for the synthesis of quinoxaline derivatives was developed. The construction of this quinoxaline system went through a one-pot oxidation/cyclization process. The reaction afforded a variety of products in good to excellent yields. This methodology has potential applications in the synthesis of biologically and medicinally relevant compounds. [ABSTRACT FROM AUTHOR]

Background: Deoxyribonuclease II (DNase II) is a well-known acidic endonuclease that catalyses the degradation of DNA into oligonucleotides. Only one or a few genes encoding DNase II have been observed in the genomes of many species. 125 DNase II-like protein family genes were predicted in the Trichinella spiralis (T. spiralis) genome; however, none have been confirmed. DNase II is a monomeric nuclease that contains two copies of a variant HKD motif in the N- and C-termini. Of these 125 genes, only plancitoxin-1 (1095 bp, GenBank accession no. XM_003370715.1) contains the HKD motif in its C-terminus domain. Methodology/Principal Findings: In this study, we cloned and characterised the plancitoxin-1 gene. However, the sequences of plancitoxin-1 cloned from T. spiralis were shorter than the predicted sequences in GenBank. Intriguingly, there were two HKD motifs in the N- and C-termini in the cloned sequences. Therefore, the gene with shorter sequences was named after plancitoxin-1-like (Ts-Pt, 885 bp) and has been deposited in GenBank under accession number KF984291. The recombinant protein (rTs-Pt) was expressed in a prokaryotic expression system and purified by nickel affinity chromatography. Western blot analysis showed that rTs-Pt was recognised by serum from T. spiralis-infected mice; the anti-rTs-Pt serum recognised crude antigens but not ES antigens. The Ts-Pt gene was examined at all T. spiralis developmental stages by real-time quantitative PCR. Immunolocalisation analysis showed that Ts-Pt was distributed throughout newborn larvae (NBL), the tegument of adults (Ad) and muscle larvae (ML). As demonstrated by DNase zymography, the expressed proteins displayed cation-independent DNase activity. rTs-Pt had a narrow optimum pH range in slightly acidic conditions (pH 4 and pH 5), and its optimum temperature was 25°C, 30°C, and 37°C. Conclusions: This study indicated that Ts-Pt was classified as a somatic protein in different T. spiralis developmental stages, and demonstrated for the first time that an expressed DNase II protein from T. spiralis had nuclease activity. [ABSTRACT FROM AUTHOR]

An abstract of the article on the catalyzed one-pot synthesis of pyrrolo is presented.