UV curing of perfluoro-alkyl-polyacrylate resins able to impart water as well as oil-repellency to cotton fabrics was studied
in comparison with conventional thermal polymerization. The process was assessed through weight gain and gel content measurements
while the properties conferred to cotton fabrics were determined in terms of water and oil contact angles, moisture adsorption,
and water vapor permeability. The polymerization yields were of the same order (>80 %) of those obtained with thermal curing
as well as the high contact angles with water (>127°) and oil (>118°) even at low resin add-on (3 %). UV cured resins yielded
oil contact angles mostly higher than 120° denoting super oil-repellent surfaces. Moreover the water and oil-repellency was
adequately maintained after washing. The moisture adsorption of finished fabrics was lower than that of untreated cotton,
but slightly higher for UV cured than thermally treated fabrics. Water vapor transmission rate showed that the finish treatment,
thermal as well as by UV curing, does not reduce the breathability of the original cotton. DSC analysis demonstrated that
the fiber pyrolysis is affected by the polymer add-on, while FTIR-ATR spectra of all finished fabrics showed typical peaks
of ester and C-F groups. XPS analysis showed small differences between thermal and UV curing coatings with each resin, while
coatings with the lowest percentage of fluorine groups did not affect the water and oil-repellency. 相似文献
This meta‐analysis based on 19 studies from Finland comprising 43 grass silages was undertaken to evaluate the effect of silage quality on liquid yield, liquid composition and retained compounds in liquid using four different liquid–solid separation methods. Silages were classified according to species (grass, clover or a mixture of them), additive treatment (no, biological or formic acid‐based additive) and harvest (primary growth or regrowth). A mixed model regression analysis with random study effect was used to evaluate the impact of silage characteristics on biorefinery efficiency. There was a large variation in silage quality in the data set. Silage dry‐matter concentration was the characteristic most highly correlated with liquid yield for all separation methods, and when used as an independent variable in the model, it resulted in the best predictions. The liquid–solid separation methods presented a great variation in the liquid yield, ranging from 0.26 to 0.56 when silage dry‐matter concentration was standardized to 250 g/kg. There was no effect of additive treatment and harvest in the estimation of the biorefinery potential, but species was a significant variable in predicting liquid yield for the laboratory‐scale presses with higher liquid yield for mixed grass and legume. The high correlation between silage quality and liquid yield and liquid composition provides potential to predict the biorefinery potential based on equations developed for each separation method. This information can be used to modify the silage production systems so that they best meet the requirements of a green biorefinery process. 相似文献
The savannah of central Brazil occupies 208 million ha, of which about 54 million ha have been converted to cultivated pasture. The aim of this study was to provide the dynamics of evapotranspiration (ET) in a Brachiaria brizantha cultivated pasture in the Brazilian Savannah region at the beginning of the rainy season and determine biological and environmental factors that influence ET by using the decoupling approach. A meteorological station and an eddy covariance system were placed at the studied site. The above‐ground biomass production of the B. brizantha pasture responded rapidly to the onset of the rainy season. Leaf area index (LAI) increased from 0·4 to 1·1 between 15 November and 3 December, with a corresponding increase in live biomass. Average ET during the study period was 2·6 ± 0·9 mm. Daily ET was significantly correlated with maximum vapour pressure deficit and precipitation. The average of daytime decoupling factor obtained over 2 d without rain was 0·50 ± 0·06. The B. brizantha pasture deployed in this region showed an intermediate coupling which takes ET to be influenced by both atmospheric conditions and by the available radiation at the canopy. 相似文献
A case of hemangiosarcoma of the third eyelid in a 15-year-old Domestic Short-haired cat is reported. A small red mass protruding from the anterior surface of the third eyelid in the left eye was present. Only mild bilateral conjunctivitis and nuclear sclerosis were revealed on initial ophthalmic examination. After anti-inflammatory treatment, surgery and cryotherapy were performed. On histopathologic examination the mass was located just beneath the conjunctival epithelium, suggesting that the conjunctiva was the tissue of origin. The tumor showed high cellularity and was composed of pleomorphic spindle and polygonal cells arranged in interlacing bundles and solid sheets. The presence of slit-like spaces between tumor cells containing erythrocytes demonstrated the vascular differentiation. Mitotic activity was moderate, but atypical mitoses were detected. The surgical area healed uneventfully and after 7 months there was no recurrence. To the authors' knowledge, this is the first report of conjunctival hemangiosarcoma of the third eyelid in a cat. 相似文献
Marine sponges belonging to the phylum Porifera (Metazoa), evolutionarily the oldest animals are the single best source of marine natural products. The present review presents a comprehensive overview of the source, taxonomy, country of origin or geographical position, chemical class, and biological activity of sponge-derived new natural products discovered between 2001 and 2010. The data has been analyzed with a view to gaining an outlook on the future trends and opportunities in the search for new compounds and their sources from marine sponges. 相似文献
Summary The in vitro antimicrobial activity of extracts from accessions ofSolanum commersonii Dun. collected in the south of Uruguay was investigated against five microorganisms including the pathogenRalstonia solanacearum. A total of 30 extracts corresponding to organic and aqueous extracts were studied. Interestingly, most of the positive results
for growth inhibition were againstR. solanacearum. The extracts were also analyzed for the presence of glycoalkaloids and lectins. Six of the ten aqueous extracts showed lectin
presence and a wide variation in the type and amounts of glycoalkaloids, was found. Results indicate that there is no clear
relationship between the antimicrobial activity against the five microorganisms screened and the presence or amounts of lectins
and glycoalkaloids, traditionally regarded as possible antimicrobial metabolites in theSolanum genus, which indicates the presence of as yet unidentified antimicrobial compounds. 相似文献
Abstract 1. Carcass cuts, chemical composition, colour, textural parameters, fatty acid and amino acid profiles, macro- and micromineral content and sensory properties of breast and drumstick meat from 10 month old common pheasant produced in an extensive rearing system were analysed.
2. Breast muscle was characterised by a high concentration of protein (254 g/kg), low content of intramuscular fat (1.3 g/kg), considerable amount of Fe-haeme (4.9 mg/kg) low shear force (1.96 kg/cm2) and hardness (4.07 kg/cm2).
3. The main drumstick characteristics were 222 g of protein/kg, 4.0 g of intramuscular fat/g and a significant higher cholesterol concentration compared to that of breast (7.7 vs. 2.9 g/kg).
4. Saturated, monounsaturated and polyunsaturated fatty acid mean values for both muscle types were approximately 34.5%, 43.3% and 24.2% of total fatty acid methyl esters, respectively, and n-3 content in breast was significantly higher (3.21% vs. 1.65%). Significant differences were found between the three tissues (breast, drumstick and subcutaneous fat).
5. Large differences in the amino acid profile between breast and drumstick were detected, especially in the non-essential fraction. The main essential amino acids were lysine and leucine, whereas aspartic and glutamic acids were the most important non-essential amino acids.
6. There were significant differences between muscle types in the mineral content with regard to iron, magnesium, sodium and zinc. Pheasant meat is a good nutritional source of iron as 100 g of drumstick may provide 23.6% of the recommended daily amount. 相似文献
Soil organic matter (SOM) is an important factor influencing aggregate stability. Interactions between SOM and soil structure are widely studied, although the subtle relationship between SOM content, pore size distribution and aggregate stability is not fully known. Here we investigate such a relationship by means of a long‐term experiment established in 1962 in northeastern Italy, which considers different fertilizer practices (organic, mineral and mixed) applied to a continuous maize crop rotation. We measured wet stability of 1–2 mm aggregates subjected to different pretreatments. Both soil physical properties (such as pore size distribution and hydrophobicity) and chemical properties (soil organic and humic carbon content) affecting aggregate stability were considered. The chemical structure of humic substances was characterized by thermal and spectroscopic analyses (TG‐DTA, DRIFT and 1H HR MAS NMR). The Pore‐Cor network model was then applied to evaluate the contribution of hydrophobicity and porosity to aggregate wetting. Our study suggests that SOM and its humic fraction can affect aggregate wetting and consequently slaking by modifying the pore size distribution with a shift from micropores (5–30 µm) and mesopores (30–75 µm) to ultramicropores (0.1–5 µm); hydrophobicity was also increased as a result of different humic composition. Spectroscopic analysis showed that hydrophobic compounds were mostly associated with complex humic molecules. Models of fast wetting dynamics, however, suggest that the contribution that hydrophobicity makes to aggregate stability, especially to soils with large carbon inputs, may not be the most significant factor. 相似文献
Banana has been currently indicated as a good source of fructooligosaccharides (FOS), which are considered to be functional components of foods. However, significant differences in their amounts in bananas have been observed in the literature. This work aims to identify and quantify FOS during ripening in different banana cultivars belonging to the most common genomic groups cultivated in Brazil. Considering that these differences can be due to cultivar, stage of ripening, and the methodologies used for FOS analyses, sugar contents were analyzed by high performance anion exchange chromatography-pulsed amperometric detection (HPAEC-PAD) and gas chromatography-mass spectrometry (GC-MS). An initial screening of eight cultivars (Ouro, Nanic?o, Prata, Ma??, Mysore, Pacovan, Terra, and Figo) in a full-ripe stage showed that 1-kestose, the first member of the FOS series (amounts between 297 and 1600 microg/g of DM), was accumulated in all of them. Nystose, the second member, was detected only in Prata cultivar. Five of the cultivars were analyzed during ripening, and a strong correlation could be established with a specific sucrose level ( approximately 200 mg/g of DM), which seems to trigger the synthesis of 1-kestose (the low amounts of FOS, below the functional recommended dose, indicates that banana cannot be considered a good source of FOS). 相似文献