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91.
Siara Silvestri Bruno Hennemann Nilo Zanatta Edson Luiz Foletto 《Water, air, and soil pollution》2018,229(2):40
In this work, disks containing different amount of the TiO2 precursor impregnated on the raw red clay were produced. The disks were obtained by pressing in metal template and subsequently calcined at 500 °C. The raw clay was used as rigid support to fix the TiO2. The materials were characterized by X-ray diffraction, diffuse reflectance spectroscopy, N2 adsorption-desorption (BET and BJH), scanning electron microscopy, and Fourier transform infrared (FTIR) spectroscopy. The ability of disks to produce superoxide and hydroxyl radicals after photoexcitation with UV irradiation was monitored by EPR. The catalytic efficiency was evaluated by the Reactive Red 141 dye discoloration under artificial UV light and sunlight. The reaction parameters such as concentration of RR-141 and irradiation source were evaluated. The results showed that the disks were able to decolorize 97.5% under sunlight at 60 min. The disks were also efficient in the discoloration until the tenth cycle, resulting in discoloration values near the initial cycles. Additionally, the dye fragments produced in cleavage of molecule during the reaction were evaluated by LC/MS-MS. 相似文献
92.
Jivago Schumacher de Oliveira Michel Brondani Evandro Sttoffels Mallmann Sérgio Luiz Jahn Edson Luiz Foletto Siara Silvestri 《Water, air, and soil pollution》2018,229(12):386
CoFe2O4/Zn2SnO4 composite was synthesized using a simple two-step process and applied as a novel-efficient photocatalyst for the rhodamine B degradation from aqueous solution. Characterization techniques such as X-ray diffraction (XRD), N2 adsorption-desorption isotherms, scanning electron microscopy (SEM), EDS analysis, and diffuse reflectance spectroscopy were employed in order to investigate the physical and chemical properties of composite. Higher values of the specific surface area, pore volume and diameter, and a smaller band-gap energy promoted a greater catalytic activity of CoFe2O4/Zn2SnO4 composite when compared to Zn2SnO4. A rapid decolorization of dye solution was observed at 40 min of reaction using the CoFe2O4/Zn2SnO4 catalyst, being 2.5 times faster than the Zn2SnO4 alone. Therefore, the CoFe2O4/Zn2SnO4 composite shows extraordinarily high photocatalytic activity toward the degradation of rhodamine B dye from aqueous solution. 相似文献
93.
Márcio Fléquisson Alves Miranda Maria Betânia Galvão dos Santos Freire Brivaldo Gomes Almeida Fernando José Freire Luiz Guilherme Medeiros Pessoa 《Archives of Agronomy and Soil Science》2018,64(9):1207-1221
This study aimed to evaluate the use of phytoremediation and soil conditioners in the recovery of physical attributes of a saline-sodic Fluvic Neossol in Brazil Northeast. The applied treatments were: Atriplex nummularia L., as phytoremediation plant, due to its ability to extract salts from the soil; organic conditioners, such as bovine and sheep manure; gypsum and polymer, as chemical conditioners. Samples with preserved structure were collected at the time of the experiment installation and 18 months after in the layers 0–10 cm and 10–30 cm. The analyzed attributes were: water dispersed clay, dispersion index, bulk density, penetration resistance, soil porosity, and saturated hydraulic conductivity. The use of sheep manure, gypsum and polymer promoted an increase in saturated hydraulic conductivity in the 0–10 cm layer from 4.51 to 16.37 cm day?1, 11.26 to 23.95 cm day?1 and 7.24 to 22.77 cm day?1, respectively. Gypsum increased the macroporosity in the superficial layer by 42.6%. Atriplex and polymer were more efficient at reducing soil penetration resistance. The polymer was more efficient at improving the physical properties. However, it is necessary to consider phytoremediation with Atriplex as a more sustainable alternative that can still be used as complementary fodder in animal feed. 相似文献
94.
95.
Daniela?Correia?MartinoEmail author Jorge?Luiz?Colodette Richard?Chandra Jack?Saddler 《Wood Science and Technology》2017,51(3):557-569
The steam explosion (SE) pretreatment associated with the organosolv process was investigated to produce dissolving pulp from eucalyptus. Prehydrolysis Kraft (PHK) pulping was also done to produce viscose and acetate grade pulps as reference. The organosolv pulps were delignified in two steps with sodium chlorite. Viscose and acetate grade PHK pulps were bleached by OD0(EH)D1P and OD0(EP)D1PCCE sequences, respectively. Dilute acid-catalyzed (with acid addition) SE pretreatment dissolved more xylan than auto-catalyzed (no acid addition) SE pretreatment. Steam-exploded unbleached organosolv pulps showed lower residual lignin content and screened yield than unbleached organosolv pulps without SE pretreatment. Steam explosion pretreatment helped to decrease lignin content and damaged fiber length of unbleached organosolv pulps. The 1.0% H2SO4 organosolv pulp (organosolv dissolving pulp at bioconversion conditions) showed the highest reactivity. Even showing low viscosity for some applications, in general, the organosolv dissolving pulps produced in this study can be used for making lyocell fibers. 相似文献
96.
Samuel Vasconcelos Valadares Víctor Hugo Alvarez V. Jefferson Luiz de Aguiar Paes Caio Buainain Lins Roberto Ferreira Novais 《Communications in Soil Science and Plant Analysis》2017,48(15):1834-1842
We assessed the sensitivity of mixed exchange resin (MER) and Mehlich-3 (M3) to calcium-bound phosphate (Ca-P) in Oxisols. These methods were compared with Mehlich-1 (M1) and anion exchange resin (AER), which have high and low sensitivity, respectively, to this soil P form. We used maize (Zea mays L.) as a test plant. Three samples from two Oxisols were treated with five ratios of Triple Superphosphate—TS and Bayóvar Phosphate Rock—BPR (0 + 100; 25 + 75, 50 + 50, 75 + 25 and 100 + 0% TS + BPR). The MER extracted more P than AER and M3 at the highest BPR:TS ratios (high Ca-P) and similar quantities at the higher TS:BPR ratios (low Ca-P) for two soil samples. Unlike M1-extracted P, M3-P, AER-P, and MER-P positively correlated with maize dry matter production and P uptake. Mehlich-3 and MER were suitable to assess P availability in high Ca-P Oxisols. 相似文献
97.
Samuel Luiz Fioreze João Paulo Costa Carneiro Daniela Dias Pinto João Domingos Rodrigues 《Journal of plant nutrition》2017,40(18):2602-2610
We characterized the pollination and fecundation times in soybean flowers and evaluated the effects of kinetin and calcium applications on physiological and productive traits of soybean plants during the reproductive stage. The anatomical study of flowers of eight soybean cultivars showed that fecundation occurred in closed flowers with visible petals, which presented embryo in the first cell divisions. These results indicate that fertilizers and growth regulation applications should be performed before flower opening, which is different from the current recommendation. Foliar applications of kinetin and calcium between the floral bud and full flowering stages did not affect carbon dioxide (CO2) assimilation, yield components and final yield. The results obtained in this research showed the lack of viability of foliar application of calcium and kinetin in order to increase pod set and number of seeds per plant in soybean crop. 相似文献
98.
Luiz Paulo Dornelas dos Santos Mário Lúcio Pereira Cunha Thaísa Fernanda Oliveira Priscila Maria de Aquino Natália Silva Assunção 《Journal of plant nutrition》2017,40(5):624-631
Garlic plants demand high quantities of nutrients, and fertilizers recommendations are necessarily evaluated for the availability of attributes such as recovery efficiency. The objective of this study was to evaluate the recovery efficiencies of nitrogen (N), phosphorus (P) and potassium (K) by micropopagated and conventionally propagated garlic plants. Two experiments were conducted in a greenhouse containing a sample of a Red Yellow Latosol, arranged in randomized blocks with five replications. Treatments consisted of four combinations of nutrients (kg per hectare): complete NPK (240-1200-550), without N (0-1200-550), without P (240-0-550) and without K (240-1200-0). Micropopagated plants maintained adequate contents of N, P, and K, as well as good growth and development even without nutrients application; however, the depletion of N and K impaired the productivity of these plants. In both cultivations, recovery efficiencies of N, P and K were low and closely related to the garlic propagation. 相似文献
99.
Larissa Sarmento dos Santos Joicy Cortez Sá Diego Luiz dos Santos Ribeiro Nancyleni Pinto Chaves Juliana Pinto da Silva Mol Renato Lima Santos Tatiane Alves da Paixão Alcina Vieira de Carvalho Neta 《Tropical animal health and production》2017,49(4):675-679
The aim of the current study is to diagnose Brucella spp. infection using methods such as serology, bacterial isolation, and molecular analysis in buffaloes bred in Maranhão State. In order to do so, 390 samples of buffalo serum were subjected to serological tests, to Rose Bengal Plate Test (RBPT) and to 2-mercaptoethanol (2-ME) combined with slow agglutination test (SAT). Vaginal swabs were collected from seropositive animals and subjected to bacterial isolation and to generic PCR. According to the serological test, 16 animals had a positive reaction to the confirmatory test (2-ME/SAT). As for bacterial isolation, three samples resulted in the isolation of Brucella spp.-characteristic colonies, which were confirmed through PCR. These results confirmed Brucella spp. infection in the buffalo herd from Maranhão State. 相似文献
100.
Beatriz King-Díaz Flávio José Leite dos Santos Dalton Luiz Ferreira-Alves Blas Lotina-Hennsen 《Pesticide biochemistry and physiology》2010,96(3):119-126
6α,7β-Dihydroxyvouacapan-17β-oic acid (1) and methyl 6α,7β-dihydroxyvouacapan-17β-oate (8) were isolated from Pterodon polygalaeflorus Benth. 1 was modified to obtain 6α-hydroxyvouacapan-7-β,17β lactone (2). Then, 6-oxovouacapan-7β,17β lactone (3) was obtained from 2. The furanoditerpene ester derivatives: propyl 7β-hydroxy-6-oxovouacapan-17β-oate (4), butyl 7β-hydroxy-6-oxovouacapan-17β-oate (5), 2-methoxyethyl 7β-hydroxy-6-oxovouacapan-17β-oate (6) and 3-methylbut-2-enyl 7β-hydroxy-6-oxovouacapan-17β-oate (7) were synthesized from (3) and methyl 6α,7β-thiocarbonyldioxyvouacapan-17β-oate (9) was obtained from (8). In this work, the lactone ester derivatives 4-7 and 9 were tested on photosynthetic activities in an attempt to search for new compounds as potential herbicide agents that affect photosynthesis. All compounds inhibited ATP synthesis and electron flow from water to MV, therefore, they act as Hill reaction inhibitors, being 4- to 9-fold more potent than 2 and 3 as inhibitors of ATP synthesis. Their interaction site was located at PSII in a similar way to diuron. Furthermore, furanoditerpene esters 6 and 7 act as uncouplers, and were corroborated by enhancement of the light-activated Mg2+-ATPase, while 5 act as an energy transfer inhibitor. Finally 5-7 behave as herbicides, since they inhibit the biomass production of weeds assay. 相似文献