Workmanhensley5880
The ultrathin shell and interconnected three-dimensional (3D) porous structure of M-MSMs can increase the mass transfer and protect the Au NPs from leakage, which reveals high recyclability and high conversion (>95%) after 10 regeneration-catalysis cycles. This approach provides a nanotechnology platform for the preparation of mesoporous silica materials with different microstructures, which will have enormous potential in practical applications involving different molecular sizes.The collisional excitation kinetics of atomic oxygen was studied behind reflected shock waves using tunable diode laser absorption spectroscopy. A test gas mixture of 1% O2/Ar was shock-heated to temperatures between 8000 and 10,000 K and pressures between 0.15 and 1 atm. The time evolution of the atomic oxygen population in the 3 s 5S0 state was monitored by laser absorption at 777.2 nm. The measured O(3 s 5S0) population revealed multistage behavior that was not observed in previous measurements over a temperature range of 5300-7200 K. To interpret the multistage behavior, a three-level collisional-radiative model for atomic oxygen excitation kinetics was developed. The model utilized two independent temperatures, that is, heavy particle translational temperature Ttr and electron translational temperature Te, to describe the fundamental rate constants of atomic oxygen excitation because of collisions with heavy particles and electrons, respectively. The heavy particle excitation rate was inferred from the early stage of the measurement to be k(3P →5S0) = 3.4 × 10-27 (T/K)0.5(1.061 × 105 + 2 (T/K)) exp(-1.061 × 105 K/T) ± 50% m3 s-1. The electron impact excitation rate constant of oxygen, electron impact, and heavy particle impact ionization rate constants of Argon were modified in the model to match the experimental population time histories. The modified rate parameters are also reported for the temperature range explored in the current study.With the intention to provide a robust and economical model that can be used for predicting particle interactions with the pulmonary surfactant, this study was aimed to find an artificial surfactant model that perfectly mimics the properties of the natural pulmonary surfactant. Cloperastine fendizoate A surfactant model should be reproducible, robust, and able to predict interactions between the pulmonary surfactant and exogenous influences from air and the aqueous site. We compared three synthetic models with the natural bovine surfactant Alveofact. The lung conditions were simulated by spreading the surfactants at the air/aqueous interface on a Langmuir trough with movable barriers. All three artificial surfactant models showed properties very similar to that of Alveofact. Visualization of the monolayers by atomic force microscopy revealed very similar structures with domain formation. The Tanaka lipid mixture has already shown good results in vitro and in vivo in previous studies. The 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC)-1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) model has large conformations in the surface pressure isotherms and showed a biomimetic exclusion plateau, indicative of an effective lung surfactant formulation. Also, the equilibrium spreading pressure was similar. DPPC-1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-1'-rac-glycerol (POPG) had the greatest similarities with Alveofact in the hysteresis areas. The kinetic constants of the relaxation experiments during desorption showed that the PCPG model (at 30 mN/m) had almost identical diffusion and dissolution values as Alveofact. As a proof of concept, the interaction of the models with PLGA nanoparticles showed promising results in all experiments for all the three surfactant models. The results show that the choice of components in a model play a crucial role in obtaining reproducible results. The selected models can be used for further studies as synthetic in vitro lung models.We report a facile approach to fabricate Ag-embedded fullerene (C60) catalyst by chemical reduction of AgNO3 complex encapsulated fullerene microcrystal, on which enhanced catalytic reduction of 4-nitrophenol was observed, because of strong absorption and propagation of H2 along the fullerene surface. With an aid of visible light radiation, photo-degradation of orange G dye is achieved, due to the formation of electron donor-acceptor dyad between Plasmon Ag nanostructures and fullerene molecules, which effectively offsets the "electron-hole" recombinant. Neither Ag nanoparticle nor fullerene crystal used in isolation could perform this chemical conversion, implicating that the metal/fullerene hybrid structure is imperative for pursuing catalytic reaction. The obtained Ag-embedded fullerene crystal is characterized by SEM, associated EDX imaging and XPS and demonstrates the present hybrid materials would add a supplemental member to a family of photocatalysts, towards the organic synthesis and wastewater remediation.Saponins of Panax notoginseng (Burk.) F.H. Chen have been classified as a type of composition in functional foods for numerous diseases. However, its mild effects and other characteristics limited clinical applications in diseases. Inspired by "nine steaming and nine processing" of P. notoginseng in traditional Chinese medicine, we developed a "steaming"-mimic protocol, which significantly changed the composition of saponins of P. notoginseng from the original, R1, Rg1, Re, Rb1, and Rd (raw-PNS), to the products after steaming, 20S/R-Rh1, Rk3, Rh4, 20S/R-Rg3, Rk1, and Rg5 (N-PNS). Surprisingly, N-PNS demonstrated promising activities in improving hyperlipidemia and reducing body weight and weight of white adipose tissue and the inhibition of adipogenesis in obese mice. In accordance with the results in vivo, N-PNS remarkably blunted adipogenesis at the early stage of differentiation dose-dependently in vitro. Moreover, we demonstrated that the activity may involve the adenosine monophosphate (AMP)-activated protein kinase (AMPK) signaling pathway by promoting phosphorylation of AMPKT172 and downregulating its downstream factors sterol regulatory element binding protein 1c, stearoyl-CoA desaturase 1, and fatty acid synthase. Taken together, the steaming-induced eight compositions of saponins showed a very promising function in improving hyperlipidemia and obesity both in vivo and in vitro, providing fundamental evidence for future study and application in treatment of hyperlipidemia, obesity, and other lipid-related metabolic syndromes.