Electrical discharges with liquid electrodes used in water decontamination

The results of experimental investigation of the DC electrical discharge with moving air bubbles in the electrolyte, as well as of high frequency electrical discharge with a diaphragm membrane, within a wide parameter range are presented. We investigated active component formation and enhancement of the wastewater decontamination by means of production of a disinfecting agent with a maximal content of the electrical discharge products (copper and silver ions and hydrogen peroxide).     

The influence of calcination temperature on catalytic activities in a Co based catalyst for CO2 dry reforming

The carbon dioxide dry reforming of methane (CDR) reaction could be thermodynamically favored in the range of 800 to 1,000 °C. However, the catalyst in this reaction should be avoided at the calcination temperature over 800 °C since strong metal support interaction (SMSI) in this temperature range can decrease activity due to loss of active sites. Therefore, we focused on optimizing the temperature of pretreatment and a comparison of surface characterization results for CDR. Results related to metal sintering over support, re-dispersion by changing of particle size of metal-support, and strong metal support interaction were observed and confirmed in this work. In our conclusion, optimum calcination temperature for a preparation of catalyst was proposed that 400 °C showed a higher and more stable catalytic activity without changing of support characteristics.     

Effect of Sintering Temperature on Thermoelectric Properties of p‐Bi2Te3 Alloys Produced by Gas Atomization

In this research, p‐type Bi₂Te₃–75% Sb₂Te₃ thermoelectric alloy powders were produced by gas atomization and subsequently sintered by hot pressing at different temperatures. The grain growth of the hot‐pressed samples was observed with increasing sintering temperature from 380°C to 460°C. The compressive strength increased with increasing hot‐pressing temperature due to the high relative density of bulk samples obtained at high temperatures. The effect of sintering temperature on thermoelectric (TE) properties was studied. The maximum power factor 3.48 mW/mK² was obtained for the sample hot pressed at 420°C due to the resulting high electrical conductivity and enhanced Seebeck coefficient values.     

Nanofiber‐Based Hydrocolloid from Colloid Electrospinning Toward Next Generation Wound Dressing

Nanofiber‐based hydrocolloid scaffold is prepared by colloid electrospinning of thermoplastic polyurethane (TPU)/sodium carboxymethyl cellulose (S.CMC) in tetrahydrofuran (THF)/dimethylformamide (DMF). The most suitable process of electrospinning for successful formation of fibers is investigated by controlling the concentration of polymeric solution and co‐solvent ratio. In order to accomplish high wettability, the amount of colloid (S.CMC) and the co‐solvent ratio (THF/DMF), which affects the morphology of fibers, are adjusted. Finally, the open wound healing effect is confirmed using nanofiber‐hydrocolloid from in vivo animal studies. A detailed study of the wound healing process is also demonstrated for the first time.

     

Preparation and characterization of composite gels and films containing gelatin and hydroxypropyl methylcellulose phthalate

Composite gels and films were prepared by the blending of hydrated gelatin as a base material and hydroxypropyl methylcellulose phthalate (HPMCP) at various mass ratios. A composite technology was applied to obtain improved mechanical, physicochemical, and antimicrobial properties of the gelatin used as a base material. We investigated the effects of different experimental conditions on the rheological and mechanical properties and antimicrobial activities of the composite gels, films, and solutions. The rheological values (storage modulus, loss modulus, and complex viscosity) of the composite solutions and gels increased with added HPMCP. Aerobic microorganisms, yeasts, and molds were not detected throughout the testing period in the gelatin–HPMCP composite solution. In contrast, many microorganisms were detected in the gelatin‐only samples beginning with day 3 of storage. The composite films exhibited relatively good mechanical and physical properties compared with the gelatin‐only film. The composite film containing HPMCP at a mass ratio greater than 1:4 did not dissolve in gastric juice (pH 1.2) for at least 2 h, but all other samples, including the gelatin‐only film dissolved in enteric juice (pH 6.8). © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39597.     

Phosphaannulation of Aryl‐ and Benzylphosphonic Acids with Unactivated Alkenes via Palladium‐Catalyzed C?H Activation/Oxidative Cyclization Reaction

An efficient phosphaannulation via palladium(II)‐catalyzed C H activation/oxidative cyclization by the 6‐endo mode is reported for the synthesis of 3‐substituted phosphaisocoumarins from the reaction of arylphosphonic acids with unactivated alkenes under aerobic conditions. Also, α,α‐disubstituted benzylphosphonic acids were phosphaannulated with unactivated alkenes, producing phosphaisochromanones having (Z)‐alkylidenyl groups via anti‐phosphoryloxypalladation by the 6‐exo mode.

     

Solvent- and Light-Sensitive AIEE-Active Azo Dye: From Spherical to 1D and 2D Assemblies

Fluorescent molecular assembly systems provide an exciting platform for creating stimuli-responsive nano- and microstructured materials with optical, electronic, and sensing functions. To understand the relationship between (i) the plausible molecular structures preferentially adopted depending on the solvent polarity (such as N,N-dimethylformamide [DMF], tetrahydrofuran [THF], and toluene), (ii) the resulting spectroscopic features, and (iii) self-assembled nano-, micro-, and macrostructures, we chose a sterically crowded triangular azo dye (3Bu) composed of a polar molecular core and three peripheral biphenyl wings. The chromophore changed the solution color from yellow to pink-red depending on the solvent polarity. In a yellow DMF solution, a considerable amount of the twisted azo form could be kept stable with the help of favorable intermolecular interactions with the solvent molecules. By varying the concentration of the DMF solution, the morphology of self-assembled structures was transformed from nanoparticles to micrometer-sized one-dimensional (1D) structures such as sticks and fibers. In a pink-red toluene solution, the periphery of the central ring became more planar. The resulting significant amount of the keto-hydrazone tautomer grew into micro- and millimeter-sized 1D structures. Interestingly, when THF-H₂O (1:1) mixtures were stored at a low temperature, elongated fibers were stacked sideways and eventually developed into anisotropic two-dimensional (2D) sheets. Notably, subsequent exposure of visible-light-irradiated sphere samples to solvent vapor resulted in reversible fluorescence off↔on switching accompanied by morphological restoration. These findings suggest that rational selection of organic dyes, solvents, and light is important for developing reusable fluorescent materials.     

Enhanced impact strength of compatibilized poly(lactic acid)/polyamide 11 blends by a crosslinking agent

Maleated poly(lactic acid) (PLA-g-MA) was prepared through melt grafting of maleic anhydride onto a PLA backbone with the aid of a radical initiator. PLA-g-MA thus formed was incorporated into PLA/polyamide 11 (PA11) blends as a reactive compatibilizer. By morphological observation, it was assessed that PLA-g-MA lowered the interfacial energy and strengthened the interface between PLA and PA11. However, the compatibilized PLA/PA11 blends did not show significant improvement of impact strength compared with noncompatibilized PLA/PA11 blends. Measurements of the molecular weight and impact strength of PLAs compounded with various amounts of radical initiators revealed that decreased molecular weight of PLA by the radical initiator used for the preparation of PLA-g-MA is responsible for this unexpected result. To compensate the decrease of the molecular weight, a crosslinking agent was incorporated in the preparation step of PLA-g-MA. It was found that the crosslinking agent is effective in preventing the molecular weight reduction. As a result, the impact strength of the PLA/PA11 blend was enhanced to a great extent by the PLA-g-MA prepared with the crosslinking agent.     

Toxoplasma gondii GRA9 Regulates the Activation of NLRP3 Inflammasome to Exert Anti-Septic Effects in Mice

Dense granule proteins (GRAs) are essential components in Toxoplasma gondii, which are suggested to be promising serodiagnostic markers in toxoplasmosis. In this study, we investigated the function of GRA9 in host response and the associated regulatory mechanism, which were unknown. We found that GRA9 interacts with NLR family pyrin domain containing 3 (NLRP3) involved in inflammation by forming the NLRP3 inflammasome. The C-terminal of GRA9 (GRA9C) is essential for GRA9–NLRP3 interaction by disrupting the NLRP3 inflammasome through blocking the binding of apoptotic speck-containing (ASC)-NLRP3. Notably, Q200 of GRA9C is essential for the interaction of NLRP3 and blocking the conjugation of ASC. Recombinant GRA9C (rGRA9C) showed an anti-inflammatory effect and the elimination of bacteria by converting M1 to M2 macrophages. In vivo, rGRA9C increased the anti-inflammatory and bactericidal effects and subsequent anti-septic activity in CLP- and E. coli- or P. aeruginosa-induced sepsis model mice by increasing M2 polarization. Taken together, our findings defined a role of T. gondii GRA9 associated with NLRP3 in host macrophages, suggesting its potential as a new candidate therapeutic agent for sepsis.