Halloysite Nanotubes Supported Gold Catalyst for Cyclohexene Oxidation with Molecular Oxygen

The selective oxidation of cyclohexene to 2-cyclohexene-1-ol and 2-cyclohexene-1-one has been investi-gated over Au/HNTs (HNTs: halloysite nanotubes) catalysts with molecular oxygen in a solvent-free system. The catalysts were prepared by deposition precipitation method and characterized by ICP-AES, TEM and XRD. The results show that the catalytic performance of Au/HNTs is quite well and the catalytic activity over recycled catalyst remains highly. Moreover, the nano-size effect of gold is also reported for the reaction.

Characterization and functional divergence of genes encoding sucrose transporters in oilseeds castor bean

Castor bean(Ricinus communis L.)is an economically important non-edible oilseed crop.Its seed oils are rich in hydroxy fatty acid,which are highly valuable with a wide range of industrial applications.Sucrose transportation is critical in regulating the growth,development and oilseed yield in castor bean.The transporters or carriers(SUTs or SUCs)play a central role in orchestrating sucrose allocation and aiding in plant adaptation to diverse stresses.In this study,based on castor bean genome,three RcSUCs(RcSUC2,RcSUC3 and RcSUC4)were identified and characterized.The expressional profiles of RcSUCs in different tissues such as leaf,stem,root,phloem and seed tissues exhibited a distinct divergence of gene expression,suggesting that the functions of RcSUC2,RcSUC3 and RcSUC4 are differentiated into long or short-distance transportation among tissues.Additionally,under abiotic stresses including hot temperature,low temperature,drought and salt stresses,the sugar allocation among leaf,stem and roots was tested.The expressional changes of Rc SUCs in leaf,stem and root tissues were associated with sugar transportation and allocation.Taken together,the differential expression of Rc SUCs among tissues responsing to abiotic stress suggested functional differences in sucrose transport and redistribution in different tissues.This study is helpful to understand the physiological and molecular mechanisms of sucrose transportation and allocation among tissues in heterotrophic oilseeds,and could provide clues for genetic improvement and optimization of cultivation practices.

Identification of KCS gene family and functional analysis of FAE-like genes from Malania oleifera

KCS(3-ketoacyl-CoA synthase)is the key enzyme catalyzing the first step of very long chain fatty acid(VLCFA)biosynthesis.Studies showed that different KCSs possessed different substrate preference.Malania oleifera are abundance of VLCFAs in its mature seeds,especially the nervonic acid,which is essential for human health.In this study,we identified and characterized 18 KCS genes in M.oleifera genome.Phylogenetic analysis showed that these KCS genes were classified into four subfamilies,including two FAE-like,six KCS-like,eight FDH-like and two CER6.We concentrated on the functional role of two FAE-like genes,Maole003085.T1 and Maole004215.T1 which encoded predicted amino acid residues of 516 and 518 in protein,respectively.Multiple sequence alignment showed that their two proteins contained the known and conserved active sites among FAE-like subfamily.Upon heterologous expression in wild type yeast(Saccharomyces cerevisiae)INVSc1,we found that Maole004215.T1 could produce four new fatty acids including C22:0/C22:1 and C24:0/C24:1,but Maole003085.T1 only produced C22:1.Besides,upon heterologous expression in mutant yeast BY4741-△elo3,we found the Maole003085.T1 could produce C24:0 and C26:0,while the Maole004215.T1 could catalyze the formation of fatty acids C24:0,C26:0 and C28:0.These results showed Maole003085.T1 and Maole004215.T1 had fatty acid elongation activity in yeast,and possessed different substrate preference in the production of different VLCFAs.Interestingly,we found Maole004215.T1 could produce nervonic acid in yeast,which provides molecular basis on the genetic improvement and genic engineering for producing nervonic acid resources by using biotechnological methods.

The Preparation and Sintering Behavior of Ce_(0.8)Sm_(0.2)O_(2-d) Electrolyte and(NiO-CuO)/Ce_(0.8)Sm_(0.2)O_(2-d) Anodes for Solid Oxide Fuel Cells

The co-pressing and co-firing processes are often used to prepare the anode-electrolyte half cells for solid oxide fuel cells(SOFCs).To get a half cell without cracks,the sintering behavior of electrolyte and anode layers must be controlled carefully.In this work,the sintering behavior

The Synthesis and Characterization of Sr-Y Doped BaCeO_3

Doped BaCeO_3 is a kind of proton conductor which exhibits high electrical conductivities at relatively low operating temperatures.It has been used as the electrolyte materials for proton ceramic fuel cells,and the effects of dopants on the sinter-ability and electrical performance are critical factors.

Better Oxygen Transport Properties and Chemical Stability of La_2NiO_4 Compared with Those of Sr-Fe Doped Lagao_3

Mixed conductors of oxygen ion and electron are important materials.They have been used as oxygen permeation membranes or electrodes of fuel cells.Doped LaGaO_3 and La_2Ni O_4 are both mixed conductors,but they have different crystal structures which will result in different

Ultrasonic Effect on Fabrication of Intercalated Mg Al-LDH/PVA Nanocomposite Via Exfoliation-adsorption Route

Preparation for Glycine-Mg/Al-Layered dou-ble hydroxide(LDH-G)/PVA nanocompositeswas carried out via exfoliation-adsorption routebased on exfoliation of LDH-G in formamide.Theeffect of ultrasonic treatment on the fabrication ofLDH-G/PVA nanocomposites was investigated,and the thermal stability of PVA containing the na-no-scale dispersed LDH-G was analyzed.The re-sults of XRD suggest that chains of PVA with

Unraveling the modulation essence of p bands in Co-based oxide stability on acidic oxygen evolution reaction

The oxygen evolution reaction(OER)electrocatalysts,which can keep active for a long time in acidic media,are of great significance to proton exchange membrane water electrolyzers.Here,Ru-Co_(3)O_(4)electrocatalysts with transition metal oxide Co_(3)O_(4)as matrix and the noble metal Ru as doping element have been prepared through an ion exchange–pyrolysis process mediated by metal-organic framework,in which Ru atoms occupy the octahedral sites of Co_(3)O_(4).Experimental and theoretical studies show that introduced Ru atoms have a passivation effect on lattice oxygen.The strong coupling between Ru and O causes a negative shift in the energy position of the O p-band centers.Therefore,the bonding activity of oxygen in the adsorbed state to the lattice oxygen is greatly passivated during the OER process,thus improving the stability of matrix material.In addition,benefiting from the modulating effect of the introduced Ru atoms on the metal active sites,the thermodynamic and kinetic barriers have been significantly reduced,which greatly enhances both the catalytic stability and reaction efficiency of Co_(3)O_(4).