Efficient photocatalytic degradation of nitrobenzene by copper-doped TiO2: kinetic study, degradation pathway, and mechanism.

Cu-doped TiO2 (0.1, 0.25, and 0.5% Cu-TiO2) photocatalyst was prepared by sol-gel method and was characterized by powder XRD, FTIR, TEM, SEM, EDX, UV-vis diffuse reflectance (DRS), photoluminescence (PL), and Raman spectroscopy. The XRD spectrum shows tetragonal anatase phase. TEM analysis indicate that the nanoparticles were spherical with sizes 12-13 nm. The degradation of NB was studied, and an optimal degradation time of 180 min led to 98.6% NB abatement of NB = 0.05 mM, pH = 4, and catalyst loading = 50 mg/100 mL, under visible light. The degradation of NB follows the pseudo-first-order kinetics. The reusability studies indicated the excellent stability of 0.25% Cu-TiO2.

Development of Ag0.04ZrO2/rGO heterojunction, as an efficient visible light photocatalyst for degradation of methyl orange.

Methyl orange (MO) is mutagenic, poisonous, and carcinogenic in nature, hence, effective methods are required for its degradation. We have synthesized pure ZrO2, Ag-doped ZrO2, and Ag-doped ZrO2/rGO as hybrid photocatalysts by facile hydrothermal method. These photocatalysts were characterized by powder XRD, scanning electron microscopy, EDX, FTIR, photoluminescence, UV-Vis diffuse reflectance (DRS), and Raman spectroscopy. The photodegradation of MO (10 ppm) was studied with pure ZrO2, Ag-doped ZrO2, and Ag-doped ZrO2/rGO (10 mg/100 mL catalyst dosage) photocatalysts at 100 min irradiation time under UV-Visible light. The pH effect and catalyst dosage on photodegradation of MO was investigated. Ag0.04ZrO2/rGO photocatalyst exhibited the maximum photocatalytic degradation of MO (87%) as compared to Ag0.04ZrO2 (60%) and pure ZrO2 (26%). Reusability experiments ensured the excellent stability of photocatalyst after five consecutive experiments. To the best of our knowledge, this is the first report on the facile hydrothermal synthesis of Ag0.04ZrO2/rGO photocatalyst for photocatalytic degradation of methyl orange.

Effect of exogenous application of micronutrients on growth and productivity of cotton (Gossypium hirsutum L. ) crop / Efeito da aplicação exógena de micronutrientes no crescimento e produtividade da cultura de algodão (Gossypium hirsutum L. )

Micronutrients play a vital role in the growth and productivity of cotton crop. A study was carried out to access the exogenous application of micronutrients on growth and yield of cotton crop. The experiment was comprised of nine treatments as T0 (control), T1 (Fe chelated), T2 (B), T3 (Mo), T4 (CuSo4 + ZnSo4 + MnSo4), T5 (CuSo4 + ZnSo4 + MnSo4 + Fe chelated), T6 (CuSo4 + ZnSo4 + MnSo4 + B), T7 (CuSo4 + ZnSo4 + MnSo4 + Mo) and T8 (CuSo4 + ZnSo4 + MnSo4 + Fe chelated + B). Data on different growth attributes showed that there was significant positive increase with the application of micronutrients. Leaf area was increased after applying micronutrients at 99 days after sowing (DAS) and then a decreasing trend was observed. Chlorophyll contents were increased at 81 DAS and then decreased towards the final harvest. Similarly, different yield components showed that seed cotton yield were significantly increased with the application of Fe, B, Mo, Zn, Cu and Mn compared to control treatment. Earliness index, mean maturity date and production rate index were increased significantly after combined use of foliar spray of Zn, Cu, Mn and Mo.

Os micronutrientes desempenham um papel vital no crescimento e produtividade da cultura do algodão. Um estudo foi realizado para acessar a aplicação exógena de micronutrientes no crescimento e produção de cultura de algodão. O experimento foi composto de nove tratamentos como T0 (controle), T1 (Fe quelatado), T2 (B), T3 (Mo), T4 (CuSo4 + ZnSo4 + MnSo4), T5 (CuSo4 + ZnSo4 + MnSo4 + Fe quelatado) T6 (CuSo4 + ZnSo4 + MnSo4 + B), T7 (CuSo4 + ZnSo4 + MnSo4 + Mo) e T8 (CuSo4 + ZnSo4 + MnSo4 + Fe quelados + B). Dados sobre diferentes atributos de crescimento mostraram aumento significativo positivo com a aplicação de micronutrientes. A área foliar foi aumentada após aplicação de micronutrientes aos 99 dias após a semeadura (DAS), observando - se, então, uma tendência decrescente. Os teores de clorofila foram aumentados em 81 DAS e depois diminuíram para a colheita final. De forma semelhante, diferentes componentes de rendimento mostraram que o rendimento de algodão de sementes aumentou significativamente com a aplicação de Fe, B, Mo, Zn, Cu e Mn em comparação com o tratamento de controlo. O índice de precocidade, a data média de maturidade eo índice de taxa de produção aumentaram significativamente após o uso combinado de pulverização foliar de Zn, Cu, Mn e Mo.