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An in situ generated AuIII catalyst is found to catalyze the direct oxidation of CH4 to C1 oxygenates in 1-ethylimidazolium bis-(trifluoromethylsulfonyl)amide ([Eim][NTf2]) at 90 °C. The formation ...

Purpose This paper aims to investigate the photocatalytic activity of zinc doped MAO-TiO2 films under the optimum MAO treatment condition. Design/methodology/approach The coating was prepared by micro arc oxidation, and the influence of doping on the properties of the coating was also investigated. Findings The results show that the BET surface area is 78.25±0.03m2/g, total pore area is 76.32 ± 0.04m2/g, and the total pore volume is 0.2135 ± 0.0004cm3/g. The degradation ratio of the film electrode with Zn-doped in methyl orange solution is up to 94%. When the react circles is 10 times, the degradation ratio is up to more than 85% and remains steady. With the different reaction conditions, these kinetics of the reactions show some different formulas. Originality/value A kinetic equation for photocatalytic activity is established.

A acetyl-substituted tetrahydrobenzofuran, 1-(4,5,6,7-tetrahydro-1-benzofuran-6-yl)ethenone (6-AcBZOF) and a acetyl-substituted tetrahydronaphthalene, 1-(1,2,3,4-tetrahydronaphthalen-2-yl)ethenone (2-AcTNAPH) were conveniently synthesized from renewable furanics by cascade Diels–Alder and dehydration reactions. The Diels-Alder cycloaddition of 4-(2-Furyl)-3-buten-2-one (4-FB) with ethylene followed by dehydration in presence of zeolites was studied. Sn grafted Beta zeolite exhibited high performance with 69% yield of 2-AcTNAPH starting from 4-FB. In this reaction, 6-AcBZOF was produced as intermediate. Further, it was found that this acetyl-substituted tetrahydrobenzofuran could be formed in high yield, 86%, in the absence of catalyst. For the first time in the literature, we report the synthesis of a renewable acetyl-substituted tetrahydronaphthalene in high yield from biomass-derived 4-FB in a tandem approach. While a acetyl-substituted tetrahydrobenzofuran could be prepared without a catalyst, catalyst was essential for the successful synthesis of the acetyl-substituted tetrahydronaphthalene.

In this work, a target-triggered three-way junction (3-WJ) structure was combined with enzyme-powered cascade amplification strategy for ultrasensitive electrochemiluminescence (ECL) detection of microRNA via free-running DNA walker. In the presence of target microRNA-21 (miRNA-21), a three-way junction structure was formed to trigger enzyme-aided multiple DNA amplification, and thus exponentially amplified triggers were generated. Then, the trigger DNA could hybridize with the blocking DNA on the electrode to release walker DNA, which specifically combined with the quantum dots (QDs)-DNA probe, and formed a recognition site for Nt.BbvCI. The movement of DNA walker is powered by the nicking endonuclease that cleaves specific QDs-DNA probes on the track. Thus one walker DNA can automatically cleave multiple QDs probes on the electrode during the movement, resulting in significantly amplified changes of ECL signal, which could be used for the highly sensitive detection of target miRNA-21. Under the optimal conditions, the ECL signal change is linear with the concentration of miRNA-21 in the range from 10−14 M to 10-7 M with a detection limit of 1.5 fM. This newly established strategy could achieve rapid, isothermal, and homogeneous signal amplification for specific nucleic acids in complicated biomatrix, which hold great potential for application in early clinical diagnosis.

Porous titanium oxide layers, which are important features for improving the biological activity of Ti implants with bone tissues, have been obtained through the technique of micro-arc oxidation (M...

Herein, we successfully devised a novel photoelectrochemical (PEC) platform for ultrasensitive detection of adenosine by target-triggering cascade multiple cycle amplification based on the silver nanoparticles-assisted ion-exchange reaction with CdTe quantum dots (QDs). In the presence of target adenosine, DNA s1 is released from the aptamer and then hybridizes with hairpin DNA (HP1), which could initiate the cycling cleavage process under the reaction of nicking endonuclease. Then the product (DNA b) of cycle I could act as the “DNA trigger” of cycle II to further generate a large number of DNA s1, which again go back to cycle I, thus a cascade multiple DNA cycle amplification was carried out to produce abundant DNA c. These DNA c fragments with the cytosine (C)-rich loop were captured by magnetic beads, and numerous silver nanoclusters (Ag NCs) were synthesized by AgNO3 and sodium borohydride. The dissolved AgNCs released numerous silver ions which could induce ion exchange reaction with the CdTe QDs, thus resulting in greatly amplified change of photocurrent for target detection. The detection linear range for adenosine was 1.0 fM ~10 nM with the detection limit of 0.5 fM. The present PEC strategy combining cascade multiple DNA cycle amplification and AgNCs-induced ion-exchange reaction with QDs provides new insight into rapid, and ultrasensitive PEC detection of different biomolecules, which showed great potential for detecting trace amounts in bioanalysis and clinical biomedicine.

Neuroinflammation is one of the important factors aggravating brain injury after ischemic stroke. We aimed to investigate the effects of cerebrolysin (CBL) on neuroinflammation in vivo and in vitro and the underlying mechanisms. The gene expressions of pro-inflammatory factors and anti-inflammatory factors were analyzed by real time PCR in rat transient middle cerebral artery occlusion (tMCAO) model, lipopolysaccharides-induced neuroinflammatory mice model and LPS-treated mouse primary microglia cells. The neuroprotective effects of CBL were evaluated by infarct size, Longa test and Rotarod test for long-term functional recovery in rats subjected to ischemia. The role of CREB/PGC-1α pathway in anti-neuroinflammatory effect of CBL was also determined by real time PCR and Western blotting. In the tMCAO model, administration of CBL at 3 h post-ischemia reduced infarct volume, promoted long-term functional recovery, decreased the gene expression of pro-inflammatory factors and increased the gene expression of anti-inflammatory factors. Correspondingly, in LPS-induced neuroinflammatory mice model, CBL treatment attenuated sickness behavior, decreased the gene expression of pro-inflammatory factors, and increased the gene expression of anti-inflammatory factors. In in vitro and in vivo experiments, CBL increased the protein expression levels of PGC-1α and phosphorylated CREB to play anti-inflammatory effect. Additionally, the application of the specific CREB inhibitor, 666-15 compound could effectively reverse the anti-inflammatory effect of CBL in primary mouse microglia cells and anti-ischemic brain injury of CBL in rats subjected to tMCAO. In conclusion, CBL ameliorated cerebral ischemia injury through reducing neuroinflammation partly via the activation of CREB/PGC-1α pathway and may play a therapeutic role as anti-neuroinflammatory agents in the brain disorders associated with neuroinflammation.

High methane dissolution capacity in a liquid is important for methane storage and transformation. In this work, methane solubility in different ionic liquids (ILs) was studied and was found associated with IL’s structural and physical properties. In imidazolium-based ILs, ILs containing C–F and long alkyl chain showed high methane solubility mainly due to lower surface tension and molar density. Reducing the surface tension of solvent by adding 0.16 mol of trimethyl-1-propanaminium iodide (FC-134) with respect to [Bmim][NTf2] increased methane solubility by 39.3%. In situ high-pressure attenuated total reflection Fourier transform infrared spectroscopic results indicated a reversible process of methane dissolution in the ILs. The antisymmetric C–H stretching band of dissolved methane in ILs showed highly prominent rotational–vibrational bands with high intensity and narrow half-peak width compared to gaseous methane. Induced interaction between methane and IL resulted in increased dipole variation streng...

Ionic liquids have been widely studied as effective reaction media for the conversion of glucose or cellulose to 5-hydroxymethhylfurfural (5-HMF). However, the recovery of 5-HMF from ionic liquids, typically carried out by extraction, has been encountered with very low extraction efficiency, which limited the reusability of the solvents. Through this work, based on the model biphasic system that consists of 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) as the ionic liquid phase and methyl isobutyl ketone (MIBK) as the extractant phase, the dominant force that suppresses the extraction efficiency of 5-HMF was identified as being the strong hydrogen bonding between 5-HMF and [BMIM]Cl. Solvent mediation with functional promoters have been established as a new strategy to shift this force, resulting in improved extraction efficiency of 5-HMF from the ionic liquid. For example, with ethanol as a promoter, the distribution coefficient of 5-HMF was about 10 times higher than that without a promoter.

Increasing the glucose loading in the 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) ionic liquid containing a dissolved CrCl3 catalyst system led to excessive formation of humins and a serious decrease in the 5-hydroxymethylfurfural (5-HMF) yield. A biphasic system containing glycol dimethyl ether (GDE) as the extraction phase, and [BMIM]Cl/CrCl3/glucose in combination with a partitioned amount of GDE and an appropriate amount of water as the reaction phase was found to be highly efficient for the reaction; CrCl3 catalyzed the formation of 5-HMF in 64.5 mol% yield from a very high glucose concentration (80 wt% with respect to the ionic liquid) at 108 °C. This 5-HMF yield in the [BMIM]Cl–GDE–H2O ternary biphasic system nearly doubled that obtained in the single [BMIM]Cl/CrCl3/glucose reaction phase. Importantly, the GDE phase contained about 56% of the generated 5-HMF without detectable contamination by the ionic liquid or carbohydrates. GDE served multiple functions: as a hydrogen-bond acceptor, it exhibited excellent extraction performance for 5-HMF; due to its low boiling point and suitable solubility saturation point in the ionic liquid, a sustained GDE bubbling phenomenon in the ionic liquid phase was observed that promoted the rate of inter-phase mass-transfer of 5-HMF in reactions; and GDE mediated the [BMIM]Cl phase to a reduced viscosity. In addition, an appropriate amount of water in the ternary system promoted the extraction efficiency of 5-HMF and also lowered the viscosity of [BMIM]Cl/glucose. The ionic liquid–organics–water ternary biphasic system has been demonstrated for high 5-HMF productivity and separation efficiency.

Objective: To develop the characterization of the polymorphs and the best preparation method of two forms of the title compound (SU2162). After SU2162 was prepared in accordance with the patent process, the crystal form I was recrystallized by ethyl acetate and the crystal form II was obtained by the recrystal in acetone. And the two crystal forms were characterized with differential scanning calorimetry (DSC) and X-ray powder diffraction (PXRD). The melting point of crystal form I (triclinic) is at 158°C, and the melting point of crystal form II (monoclinic) is at 163°C. The PXRD studies of the two crystalline samples indicate that they have the distinct diffraction patterns. The method herein can be stably prepared for the two crystal forms of the title compound.

The catalytic isomerization of aldoses to ketones is an important fundamental step for the transformation of cellulosic biomass to biobased chemicals and liquid fuels. The results of this work reveal for the first time the distinctive coordination chemistry features of four classes of metal chlorides, CrCl3, VCl3, FeCl3, and PtCl2 in 1-butyl-3-methylimidazolium chloride ([BMIM]Cl), that are well correlated to the drastically different catalytic performances of the metal chlorides in the isomerization of glucose. The relative bond strengths and the number of ligands to which the metal ions are coordinated by oxygen atoms of different sources and by chloride were studied by probing model compounds with in situ far-infrared (FIR) and by reaction studies. The superior performance of CrCl3 for this reaction is now distinguished from that of other metal chlorides, on the basis of its selective Cr(III) ene-diol coordination chemistry. We also offer new insights into the mechanism involved in the conversion of gl...

Objective: To determine the transformation between two known crystal forms of the title compound (C18H23NO3, Mr = 301.37). Methods: To recrystallize or heat the crystals and determine the crystal form by testing the melting points. Results: Both the two known crystal forms of the title compound can be changed by dissolving into different organic solvents such as acetone and ethyl acetate. Crystal form I was not influenced by heating while crystal form II can be transformed to crystal form I through melting method. Conclusion: Organic solvents have significant influences on the two crystal forms of title compound. Crystal form I shows a better thermal stability than crystal form II.