Direct Solvothermal Synthesis of B/N‐Doped Graphene

Heteroatom‐doping into graphitic networks has been utilized for opening the band gap of graphene. However, boron‐doping into the graphitic framework is extremely limited, whereas nitrogen‐doping is relatively feasible. Herein, boron/nitrogen co‐doped graphene (BCN‐graphene) is directly synthesized from the reaction of CCl₄, BBr₃, and N₂ in the presence of potassium. The resultant BCN‐graphene has boron and nitrogen contents of 2.38 and 2.66 atom %, respectively, and displays good dispersion stability in N‐methyl‐2‐pyrrolidone, allowing for solution casting fabrication of a field‐effect transistor. The device displays an on/off ratio of 10.7 with an optical band gap of 3.3 eV. Considering the scalability of the production method and the benefits of solution processability, BCN‐graphene has high potential for many practical applications.     

Determination of itopride in human plasma by liquid chromatography coupled to tandem mass spectrometric detection: application to a bioequivalence study

A simple method using a one-step liquid-liquid extraction (LLE) with butyl acetate followed by high-performance liquid chromatography (HPLC) with positive ion electrospray ionization tandem mass spectrometric (ESI-MS/MS) detection was developed for the determination of itopride in human plasma, using sulpiride as an internal standard (IS). Acquisition was performed in multiple reaction monitoring (MRM) mode, by monitoring the transitions: m/z 359.5 > 166.1 for itopride and m/z 342.3 > 111.6 for IS, respectively. Analytes were chromatographed on an YMC C₁₈ reverse-phase chromatographic column by isocratic elution with 1 mM ammonium acetate buffer-methanol (20: 80, v/v; pH 4.0 adjusted with acetic acid). Results were linear (r² = 0.9999) over the studied range (0.5-1000 ng mL⁻¹) with a total analysis time per run of 2 min for LC-MS/MS. The developed method was validated and successfully applied to bioequivalence studies of itopride hydrochloride in healthy male volunteers.     

Influence of nanobubbles on the adsorption of nanoparticles

A quartz crystal microbalance was used to study the influence of nanobubbles on the adsorption of polystyrene nanoparticles onto surfaces coated with gold, or coated with dodecanethiol or mercaptoundecanoic acid self-assembled monolayers (SAMs). Adsorption of the nanoparticles onto the surface causes the resonant frequency of the quartz crystal to decrease. We found that particles were adsorbed onto the gold-coated quartz crystal in air-rich water, but not in degassed water. This finding supports the long-standing hypothesis that nanobubbles play a key role in the long-range attractive force between hydrophobic surfaces in aqueous solutions. When the experiments were conducted using quartz crystals coated with a hydrophobic dodecanethiol SAM, the nanoparticles were adsorbed onto the surface even in degassed water due to the short-range hydrophobic interactions between the nanoparticles and the dodecanethiol molecules. In contrast, the nanoparticles were adsorbed to a lesser degree onto the hydrophilic mercaptoundecanoic acid-coated crystals due to electrostatic repulsive forces.     

Modulating Electrostatic Interactions in Ion Pair Intermediates To Alter Site Selectivity in the C−O Deoxygenation of Sugars

Controlling which products one can access from the predefined biomass-derived sugars is challenging. Changing from CH₂Cl₂ to the greener alternative toluene alters which C−O bonds in a sugar are cleaved by the tris(pentafluorophenyl)borane/HSiR₃ catalyst system. This increases the diversity of high-value products that can be obtained through one-step, high-yielding, catalytic transformations of the mono-, di-, and oligosaccharides. Computational methods helped identify this non-intuitive outcome in low dielectric solvents to non-isotropic electrostatic enhancements in the key ion pair intermediates, which influence the reaction coordinate in the reactivity-/selectivity-determining step. Molecular-level models for these effects have far-reaching consequences in stereoselective ion pair catalysis.     

Overexpression of Endogenous Xylose Reductase Enhanced Xylitol Productivity at 40 °C by Thermotolerant Yeast Kluyveromyces marxianus

Applied Biochemistry and Biotechnology - Xylitol is a valuable substance utilized by food and biochemical industries. NAD(P)H-dependent xylose reductase (XR)—encoded by the yeast KmXYL1...     

Synthesis and biological evaluation of 1,2,4-triazolidine-3-thiones as potent acetylcholinesterase inhibitors: in vitro and in silico analysis through kinetics,chemoinformatics and computational approaches

Molecular Diversity - We have designed and synthesized a novel acidic ionic liquid and explored its catalytic efficiency for the synthesis of 1,2,4-triazolidine-3-thione derivatives. A simple...     

Functional encryption for set intersection in the multi-client setting

Designs, Codes and Cryptography - Functional encryption for set intersection (FE-SI) in the multi-client environment is that each client i encrypts a set $$X_i$$ associated with time T by using its...     

Preparation of tantalum-pillared magadiite and its catalytic performance in Beckmann rearrangement

Vapor phase Beckmann rearrangement of cyclohexanone oxime to ε-caprolactam has been carried out using tantalum-pillared magadiites (Ta-magadiites) with different surface areas as catalysts. The Ta-magadiite catalysts of relatively large surface areas showed high catalytic activities, due to a large number of active sites. For the Ta-magadiite catalyst of the largest surface area, the oxime conversion reached 99.1%, with 97.5% of lactam selectivity. FT-IR and NH₃-TPD results demonstrated that the new hydroxyl groups and a large amount of acidic sites generated by Ta pillaring into the magadiite interlayer were responsible for the high catalytic performance of Ta-magadiite catalyst.