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A novel Bacillus sp. together with speedy expansion home and enzyme task that permits successful fermentation of soybean food for bettering digestibility within expanding pigs.
Development of high-performance ammonia (NH3) sensor is imperative for monitoring NH3 in the living environment. In this work, to obtain a high performance NH3 gas sensor, structurally well-defined WO3@SnO2 core shell nanosheets with a controllable thickness of SnO2 shell layer have been employed as sensing materials. The prepared core shell nanosheets were used to obtain a miniaturized gas sensor based on micro-electro-mechanical system (MEMS). By tuning the thickness of SnO2 layer via atomic layer deposition, a series of WO3@SnO2 core-shell nanosheets with tunable sensing properties were realized. Particularly, the sensor base on the fabricated WO3@SnO2 nanosheets with 20-nm SnO2 shell layer demonstrated superior gas sensing performance with the highest response (1.55) and selectivity toward 15 ppm NH3 at 200 °C. This remarkable enhancement of NH3 sensing ability could be ascribed to the formation of unique WO3-SnO2 core-shell heterojunction structure. The detailed mechanism was elucidated by the heterojunction-depletion model with the help of specific band alignment. Framework crystallization is an unresolved challenge in the chemistry of covalent organic frameworks (COFs) due to the poorly controlled simultaneous polymerization and crystallization processes. Here, we report the first morphogenesis of COF mesocrystals with two-dimensional hexagonal p6m symmetry through the combination of alkyl amine as a dynamic modulator and 2,4,6- triformylresorcinol imine as an asymmetrical building block. The amine modulator depresses the lateral growth of 2D sheets, and the slow kinetics combined with the asymmetrical conformation of 2,4,6-triformylresorcinol imine lead to the formation of transient imine macrocycles, which further undergo mesoscale self-assembly into nanotubular structures. The nanotubular structures tend to join together into rod-like bundles with ordered hexagonal rods, which finally grow into uniform hexagonal COF mesocrystals. The present strategy opens a nonclassical nucleation and crystal growth approach to create COFs with unexplored mesocrystal structures, which further extends the scope of crystalline framework materials and provides a new strategy for crystal morphogenesis. HYPOTHESIS Surfactants are commonly used as corrosion inhibitors for oil-and-gas pipelines. The alkyl chain of surfactants and their overall conformation contributes to the adsorption, flotation, and foam separation in the inhibition process. We hypothesize that the conformation of shorter alkyl chains and chemical nature of surfactants has an effect on the ordering of water molecules at the air-water interface which is not yet well understood. EXPERIMENTS Alkyl (C4, C6, C8, C10, and C12) dimethylbenzylammonium bromides (Quats) were synthesized. Aqueous solutions at 0% and with different salt concentrations were studied at the air-liquid interface using sum frequency generation spectroscopy. Stattic concentration Surface tension and pH measurement were also conducted for comparison. FINDINGS Surfactant solutions at 0%, 1%, and 10% salt showed a zigzag trend for the number of gauche defects. At 0% salt, an increasing trend of OH band intensity at 3182 cm-1 was observed from C6 to C12 SFG spectra. Yet, C4 showed a more prominent SFG signal from strongly hydrogen-bonded water molecules compared to C6. The headgroup's chemical nature was found to play a role in the ordering of water molecules for a C4 alkyl chain length. The OH band intensity decreases with increasing ionic strength. HYPOTHESIS Interfacially active magnetic Janus nanoparticles (M-Janus NPs) of asymmetric surface wettability are more interfacially active than biwettable nanoparticles (M-CMC-EC NPs) of uniform surface wettability as such that they could anchor more securely at an oil-water interface to separate emulsified oil droplets from oily wastewaters more effectively by magnetic separation. EXPERIMENTS Interfacial tension and interfacial pressure-area isotherms of M-Janus NPs at oil-water interface were measured and the results were correlated to coalescence time of oil droplets determined in various types of aqueous phase (wastewaters) and to the performance of oil removal or recovery from corresponding oily wastewaters by M-Janus NPs and M-CMC-EC NPs of uniform surface wettability by an external magnetic field. FINDINGS Despite the presence of natural/synthetic surfactants in the oily wastewaters, M-Janus NPs exhibited stronger interfacial activities and anchored more firmly at oil-water interfaces than M-CMC-EC NPs of uniform surface wettability. The application of M-Janus NPs could remove/recover >91.5% oil from oily wastewaters by an external magnetic field as compared with >84.3% achieved by M-CMC-EC NPs of uniform surface wettability for treating different oily wastewaters. The M-Janus NPs could be facilely recycled and efficiently reused in the subsequent applications to oil removal/recovery without complex regeneration. Herein, we report a simple approach to synthesize CuFeO2/TNNTs photocathodes composed of high-temperature resistance n-type Nb-doped TiO2 nanotube arrays (TNNTs) and p-type CuFeO2 for CO2 reduction. TNNTs were prepared by anodic oxidation on TiNb alloy sheets and CuFeO2/TNNTs were then prepared by coating precursor liquid onto TNNTs followed by heat treatment in argon atmosphere. The microstructures of CuFeO2/TNNTs and TNNTs before and after heat treatment were investigated by SEM and TEM. The phase compositions of CuFeO2/TNNTs were studied by XRD and XPS, and the light absorption performance were tested by UV-vis diffuse reflectance spectrum. Results show that TNNTs exhibit a regular nanotube arrays structure and this structure is well remained after the calcination at 650 °C. In addition, TNNTs show similar semiconductor properties to n-type TiO2, which enables them to be integrated with p-type CuFeO2 to obtain composite photocathodes with a p-n junction. The synthesized CuFeO2/TNNTs photocathode is well crystallized because no other crystalline iron or copper compounds are included in the prepared photocathode. Furthermore, the photocathode shows high light absorption and fast carrier transport due to the appropriate band gap and p-n junction. As a result, high photoelectrocatalytic CO2 reduction performance with high selectivity to ethanol is obtained on this photocathode.