Caracterização do meio físico da bacia do córrego caçula e processos de degradação associados com vistas ao planejamento territorial

Pós-graduação em Engenharia Civil - FEIS

Avaliação da degradação fotoquímica de corante alimentício e lixiviação de corantes têxteis de fibras de algodão expostos a suor sintético por método cromatográficos

Pós-graduação em Química - IQ

Avaliação das propriedades nanomecânicas e do comportamento micromecânico da interface dentina/adesivo antes e após a degradação hidrolítica: análises através de nanoindentação e método dos elementos finitos tridimensional

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Translocação dos herbicidas glyphosate e imazamox em plantas de aguapé

Eichhornia crassipes is one of the main weeds found in aquatic environments, being undesirable for many activities. The aim of this study was to evaluate the translocation of glyphosate and imazamox in E. crassipes. Eight intervals were studied for cutting leaves that received herbicides: 2, 4, 6, 8, 12 and 24 hours after application (HAA), and a treatment with no cutting (untreated). The glyphosate dose was 2,160 g a.e. ha-1 (commercial product - Rodeo) + 0.5% v v-1 Aterbane adhesive spreader and imazamox at 290.4 g i.a. ha-1 (commercial product - Clearcast). The treatments were installed in a completely randomized design with four replications. Glyphosate showed a bad control for all the periods of leaf cutting. The imazamox did not provide control within 12 HAA, while from 24 HAA onward the control was effective. There was not a great mobility of the glyphosate molecule in water hyacinth plants, a period above 24 hours being needed for a satisfactory translocation. For imazamox at least 24 hours were needed after herbicide application for the translocation to occur along with subsequent control.

Evolução de CO2 e atividades enzimáticas em amostras de solo tratado com herbicidas

Effects of bentazon, metolachlor, trifluralin, imazethapyr, imazethapyr+lactofen, haloxyfop-methyl, glyphosate and chlorimuron-ethyl at rates of 2 and 10 times the equivalent commercial dose on soil microbial activity was evaluated in soil samples extracted from a field never treated before. Global soil microbe respiration, estimated by CO2 production at 2, 4, 8, 12, 16, 20, 24 and 28 days of soil incubation and enzymatic activities (dehydrogenase and fluorescein diacetate hydrolysis) at 8 and 28 days were used as bioindicators. Bentazon and mixture imazethapyr+lactofen at the highest rate and haloxyfop-methyl at both rates, inhibited soil respiration although with differences in timing and duration. None of the herbicides affected FDA hydrolysis. Dehydrogenase activity was inhibited at 8 days of incubation with bentazon and imazethapyr at high rates but it was stimulated by metolachlor and imazethapyr at low rate and glyphosate at the highest rate. Herbicide effects on soil microbial activity was detected with higher sensitivity by global soil microbe respiration and dehydrogenase activity than by FDA hydrolysis. Only dehydrogenase activity and soil respiration estimations at 8 days of soil incubation had significant correlation. Results indicated the need of multiple estimations when evaluating herbicides effects on soil microbiota

Degradação de membrana impermeabilizante de polietileno de alta densidade usada em tanques de armazenamento de vinhaça

High-density polyethylene (HDPE) water-proof membranes are used as coatings in vinasse (leachate from sugar cane) storage tanks. The leachate is pumped into the tanks at temperatures of 80-90 °C. Due to these high temperatures and acidity of the waste, these membranes can be degraded, cracked and then loose the function for which they have been designed. This may cause contamination of the soil and groundwater. This study evaluated the effect of vinasse in HDPE membranes after 4 months of exposure in a controlled environment. An aggressive, alkaline pH liquid (sodium hydroxide) was also used. The objective was to evaluate the membrane resistance in contact with acidic and alkaline residues. Physical and mechanical tests, measurement of the carbon black content and thermo gravimetric analysis (TGA) were used to determine degradation of polymer membranes after chemical immersion. While sodium hydroxide resulted caused only minor changes in the physical properties, vinasse induced a thickness change of 7.8%. With immersion in vinasse, an average decrease in strength and deformability (yield) of 34% and 23.5% were measured, respectively. The stiffness increased by 7.8% (average) and the tear strength decreased by 2.7% (average).

Adubação nitrogenada e aplicação de herbicidas como reguladores de crescimento em grama esmeralda

Pós-graduação em Agronomia - FEIS

A degradação ambiental do Córrego Ribeirão Preto: uma proposta metodológica para o ensino de geografia no ensino médio

Pós-graduação em Geografia - IGCE

Degradação do corante comercial disperse red1 por processo foto-Feton e avaliação ecotoxicológica

Pós-graduação em Química - IQ

Influência da vinhaça e da palhada de cana-de-açúcar na sorção de herbicidas aplicados em diferentes solos

Pós-graduação em Agronomia (Agricultura) - FCA

Hormesis de herbicidas em soja

Pós-graduação em Agronomia (Agricultura) - FCA

Teores foliares de macro e micronutrientes em milho tolerante ao glyphosate submetido à herbicidas

A serial of factors related to development of glyphosate-tolerant corn should be approached and best studied. This work was developed to evaluate foliar levels of N, P, K, Ca, Mg, S, B, Cu, Fe, Mn and Zn, besides the grain yield of glyphosate-tolerant corn (DKB390 RR hybrid). An experiment was carried out under field conditions, during the crop year of 2010/2011. A randomized complete block design with four repetitions was used to distribute the treatments in the field. Twelve herbicide treatments were studied: glyphosate (720, 1200 and sequential application of 960 plus 720 g ha(-1) of the acid glyphosate equivalent), atrazine (2500 g ha(-1)), nicosulfuron (60 g ha(-1)), mesotrione (192 g ha(-1)), tembotrione (100,8 g ha(-1)), atrazine plus glyphosate (1000 + 960 g ha(-1)), atrazine plus nicosulfuron (1000 + 20 g ha(-1)), atrazine plus mesotrione (1000 + 144 g ha(-1)) and atrazine plus tembotrione (1000 + 75,6 g ha(-1)) and one control treatment without herbicide. The glyphosate and mesotrione alone did not cause no visible injury to corn. The other herbicides caused intoxication symptoms classified as light (<5%). The treatments studied did not affect foliar levels of N, P, K, Ca, Mg, S, B, Mn and Zn in the corn plants. But, the plants treated with atrazine plus nicosulfuron had more leaf Fe content, and the plants sprayed with glyphosate (in the three doses) and atrazine, more accumulation of Cu in the leaf. The Grain yield of corn was reduced with application single of glyphosate (1200 g ha(-1)), nicosulfuron, tembotrione and with the mixture atrazine plus nicosulfuron.

Fermentação, cinética e degradação ruminal em ovinos alimentados com fontes de carboidratos associadas ao óleo

The objective this work was to evaluate the degradation, fermentation and kinetics of passage rumen fluid en sheep fed diets containing different carbohydrate associated with the oil. Four rumen cannulated sheep were allotted in 4 x 4 latin square. The treatments consisted of diets with high neutral detergent soluble fiber and diets with high starch associated or not with 4,2% of oil. Incubation times were 3, 6, 12, 24, 48, 72, 96 and 120 hours and ruminal fluid was collected at 0, 2, 4, 6, 8, 10, 12, and 24 hours after feeding. Diets high neutral detergent fiber soluble resulted in greater degradation of dry matter, crude protein, neutral detergent fiber soluble and starch, and higher pH values, butyric acid production, dilution rate and ruminal recycling compared with diets high starch content. The inclusion of 4,2% oil the different carbohydrate sources had no influence on the fermentation kinetics and degradation of the fiber. High content of neutral detergent soluble fiber in the diet favors the ruminal fermentation compared to the high starch content.

Biomassa microbiana e degradação de serapilheira em pastos de tifton-85 manejados com índices de área foliar residual

Pós-graduação em Zootecnia - FCAV

Eficiência de herbicidas no controle de plantas daninhas latifoliadas em mamona

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)