On the Limited Role of Electronic Support Effects in Selective Alkyne Hydrogenation: A Kinetic Study of Au/MO\u3csub\u3ex\u3c/sub\u3e Catalysts Prepared from Oleylamine-Capped Colloidal Nanoparticles

We report a quantitative kinetic evaluation and study of support effects for partial alkyne hydrogenation using oleylaminecapped Au colloids as catalyst precursors. The amine capping agents can be removed under reducing conditions, generating supported Au nanoparticles of ~2.5 nm in diameter. The catalysts showed high alkene selectivity (\u3e90%) at all conversions during alkyne partial hydrogenation. Catalytic activity, observed rate constants, and apparent activation energies (25– 40 kJ/mol) were similar for all Au catalysts, indicating support effects are relatively small. Alkyne adsorption, probed with FTIR and DFT, showed adsorption on the support was associated with hydrogen-bonding interactions. DFT calculations indicate strong alkyne adsorption on Au sites, with the strongest adsorption sites at the metal-support interface (MSI). The catalysts had similar hydrogen reaction orders (0.7–0.9), and 1- octyne reaction orders (~ 0.2), suggesting a common mechanism. The reaction kinetics are most consistent with a mechanism involving the non-competitive activated adsorption of H2 on an alkyne-covered Au surface

Effects of malt bagasse utilization on kale germination using different substrates and shadings.

Malt bagasse is an important waste from breweries, with high potential of usage in various animal and human food areas. Nonetheless, there are few studies of its in natura usage as soil conditioner for various vegetables seedings production. Thus, this works objective was evaluate the interaction among different substrate compositions, using brewery waste as component, and different shading levels at Georgian cabbage germination. For that, the experiment was made in five different shading levels (50%, 70%, 90%, 70% with plastic and full sun) and three different substrates moistures with distinct compositions: S1 (33,33% of manure; 33,33% of sandy soil; 33,33% of clayish soil), S2 (83% of earthworm humus; 15% of fine glyceride charcoal; 2% of mammon dumpling), S3 (33,33% of brew waste; 33,33% of sandy soil; 33,33% of clayish soil), in an completely randomized design, with five repetitions for each shading level and substrate concentration. Germination beginning occurred in the third day after sowing (DAS) and lasted until the tenth DAS. The S2 substrate stood out, followed by S1, with similar results in height, roots length, germination percentage, and germination speed index. On the other hand, the substrate composed of malt bagasse obtained the worst results in all shading conditions, being not indicated to kale seedings production

Germination of chapolin® tomato using different substrates and shading.

Vegetable production is a great source of Brazilian income and has been widely studied. Thus, the formation of substrates that promote better seedling cultivation conditions and the amount of light received become important research factors for better results in the final product. The use of coconut fiber (FC) has been widely used in the production of seedlings of many vegetable species. Thus, the objective of this work was to evaluate the interaction of different substrate compositions and different shading levels in the germination of tomato of the Chapolin® variety. For this, the experiment was conducted at three different shading levels (70 and 90%) and 5 different mixtures of substrates with different concentrations of clay (A) and coconut fiber (FC): T1 (100% A), T2 (80 % A + 20% FC), T3 (60% A + 40% FC), T4 (40% A + 60% FC) and T5 (100% FC), in a completely randomized design, with four replications for each level of shading and substrate concentration. The beginning of germination occurred on the seventh day after sowing (DAS) and lasted until the fourteenth DAS. The type of substrate concentration with the highest germination percentage was the T2 substrate and the shading was 70%. Thus, for such experimental conditions, the concentration of 80% clay with 20% coconut fiber is indicated, when conducted in 70% shading and for 90% shading conditions, the composition of 60% clay and 40% fiber of coconut

Different lighting conditions affect the germination and seedling development of two varieties of Shiso.

Shiso (Perilla frutescens L.) is an Asian plant that contains properties that allow it to be used in both cooking and medicine. The present study set out to understand how different lighting conditions affect the germination and development of shiso seedlings of the purple and green varieties. Germination stabilization occurred 15 days after sowing (DAS), accounting for the environment with 70% shading 84 germinations of the purple variety and 34 germinations of the green variety. While, in the full sunshine treatment, germinations were much lower, however, the seedlings did not remain viable for monitoring the development of seedlings in full sunshine. After stabilization of germination, the following were evaluated: specific leaf area, diameter of the neck, height and number of leaves and but after 35 DAS there was a decrease in the production of biomass by both varieties