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191.
Dimethylaminopropyl methacrylamide (DMAPMA) was grafted onto PET/wool blend fabrics by continuous UV irradiation. Union dyeing
of the photografted fabrics was investigated using three reactive dyes of α-bromoacrylamide reactive groups. The influence of grafting yield, DMAPMA concentration, NaCl amount, pH value, and dyeing
temperature on the dyeability was evaluated. The dyeability of both PET and wool components was improved significantly by
the DMAPMA photografting and successive reactive dyeing. Although the dyeability of the PET component in the blend substantially
was improved with higher grafting, equal dyeability between PET and wool was difficult to achieve due to more facile grafting
and higher reactivity of the wool component compared with the modified PET component. However, the color fastness of the PET/wool
blend fabric was excellent for all three colors. This study may offer a way to achieve union dyeing of PET/wool blend fabrics. 相似文献
192.
Isabel Egea Paloma Sánchez-Bel Felix Romojaro Maria Teresa Pretel 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(2):121-129
Total antioxidant activity of six non-cultivated but traditionally collected fruits from the south of Europe was assessed
by measuring their ability to reduce the hydroxyl radical ( OH· ) \left( {{\hbox{O}}{{\hbox{H}}^\bullet }} \right) and hydrogen peroxide (H2O2), and their Trolox equivalent antioxidant capacity (TEAC). This antioxidant activity was compared with that shown by the
synthetic antioxidants BHA (E-320), BHT (E-321) and propyl gallate (E-310). Total phenolics, ascorbic acid and the carotenoid
content of the fruits were also analyzed. All fruits showed a high ability to scavenge the OH· {\hbox{O}}{{\hbox{H}}^\bullet } radical, ranging from 60.61% to 81.04% inhibition for Rosa canina and Crataegus monogyna, respectively. The H2O2 scavenging capacity and the TEAC value varied widely, ranging between 3.63% and 87.26% inhibition of H2O2 and between 0.47 and 416.64 mM trolox g−1 FW for Sorbus domestica and Rosa canina, respectively. The antioxidant activity of fruits was higher than that of the synthetic additives analyzed, except in the
TEAC assay. The phenolic and carotenoid content of R. canina was much higher than that of the other fruits analyzed and its ascorbic acid concentration was also high, reflecting its
higher efficacy towards ABTS ·- {\hbox{ABT}}{{\hbox{S}}^{ \bullet - }} (TEAC assay) and H2O2 species. In spite of these associations, the correlation coefficients between total antioxidant activity and the antioxidant compounds
analyzed were not very significant; only phenolics and carotenoids showed a marginal correlation with the TEAC assay. The
results support the possible use of R. canina as natural antioxidant to replace the synthetic additives, as well as their use in the production of functional foods with
a high antioxidant activity. 相似文献
193.
In this work, a novel hybrid fibrous vehicle was developed for the release and real-time detection of nitric oxide (NO). The vehicle consisted of poly(L-lactide)/chitosan (PLLACS), cadmium tellurium quantum dots (CdTe QDs), and conjugating S-nitrosothiols. CdTe QDs were placed on the surface of PLLACS fibers as NO fluorescent probes through coaxial electrospinning; in this method, the PLLACS was used as filament material. Water-dispersible CdTe QDs were synthesized using mercaptoacetic acid as a stabilizer. The amino groups of chitosan served as reactive sites where chitosanbased S-nitrosothiols were formed. The fibrous PLLACS-QDs-NO composite was found to release NO under UV. The released NO could be detected in real time on the basis of the fluorescence quenching mechanism of QDs. These PLLACSQDs-NO nanofibers provide insights into novel designs of biocompatible NO delivery systems. 相似文献
194.
Ana Flavia Camara Bezerra Laura Hecker de Carvalho Wilma Sales Cavalcanti Antonio Gilson Barbosa 《Fibers and Polymers》2016,17(11):1908-1915
Composites were prepared with 13, 23 30 and 40 % fiber and evaluated the mechanical performance in tensile, flexural and impact. The mechanical properties of these composites were also evaluated function of time at 110 °C thermal exposure. Caroa fibers were characterized by techniques such as thermal gravimetric analysis (TGA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). It was found that the best mechanical properties were achieved for composites containing 23 to 30 % fiber. The incorporation of 23 % fiber caroa increased both the modulus of elasticity in the tensile test as the flexural strength and impact, the composite with 30 % fiber caroa showed higher tensile strength. The results show that the tensile and flexural strength of the composite decreased with time of thermal exposure. The thermal aging at 110 °C caused a decrease in tensile properties of the composites. 相似文献
195.
Polypropylene fabrics were coated with copper particles using electroless plating, screen printing and wire arc spray coating techniques. Surface morphology of the fabrics was studied using optical and scanning electron microscopes (SEM). Furthermore, tensile strength, electrical conductivity, thermal conductivity, air permeability, water contact angle and fog collection efficiency of the coated fabrics were measured and the obtained results were analyzed. SEM micrographs showed that a very thin and uniform layer of copper deposited on the surface of the electroless plated polypropylene fibers. In the printed or spray coated fabrics the copper particles filled the spaces between yarns and fibers. The polypropylene electroless copper plated fabrics showed higher tensile strength, electrical conductivity, air permeability and thermal conductivity when compared with the fabrics coated with copper screen printed and copper spray coated fabrics. Finally, the obtained results showed that copper electroless plating could increase the fog collection efficiency of polypropylene fabrics considerably. As a conclusion, the surface modified copper electroless polypropylene fabrics are good candidates for fog collection in appropriate regions which need further investigations. 相似文献
196.
Zheng J He J Ji B Li Y Zhang X 《Plant foods for human nutrition (Dordrecht, Netherlands)》2007,62(1):7-11
The root of Platycodon grandiflorum (Jacq.) A. DC has been reported to have a wide range of health benefits in oriental food. This study examined the hypoglycemic
effects of Platycodon grandiflorum (Jacq.) A. DC aqueous-ethanol extract (PGE) in streptozotocin (STZ) -induced diabetic ICR mice (STZ diabetic mice) for the
first time. The effects of PGE on blood glucose, plasma insulin levels and body weight were investigated. A significant decrease
in blood glucose levels was observed after single administration of PGE. Furthermore, Glibenclamide and PGE significantly
suppressed the rise in blood glucose after 30 min in the acute glucose tolerance test. Treatment with glibenclamide and PGE
resulted in a reduction in blood glucose levels from the 2nd week, and this reduction was maintained until the 4th week of
treatment. The body weight changed slightly in glibenclamide and PGE treated mice in comparison with the STZ control group.
Plasma insulin levels were increased with glibenclamide treatment in STZ diabetic mice, whereas such effect was not observed
with PGE. These results indicated that PGE could induce hypoglycemic effects without stimulating insulin secretion. 相似文献
197.
A series of field trials combining cultivars with different levels of resistance to Phythophtora infestans and different haulm killing methods was conducted in 1997, 1998 and 1999 to assess the contamination potential of the haulm.
In addition, the frequency of tubers with late blight was assessed after harvest and storage, combining effects of pretreatment
infection, infection by the haulm at harvest and the development of the disease during storage. Haulm killing was performed
by diquat (200, 400, 600 g a.i. ha-1), half cutting of the haulm in combination with diquat (100, 200, 300 g a.i. ha-1) or full cutting of the haulm. In those treatments where haulm killing was performed purely chemically the haulm remnants’
contamination potential tended to increase at reduced doses. Full mechanical destruction gave as low a contamination potential
as application of the full dose of chemical haulm killer. However, there were no consistent differences between the haulm
killing treatments in the frequency of blighted tubers after harvest and storage. This indicates that the input of chemical
haulm killers may be reduced. There was a large difference between years in tuber blight after harvest and storage, which
confirms that climatic factors are of major importance for tuber infection. The large difference found between the cultivars
in the frequency of tuber blight indicates that tuber resistance should be an important part of integrated late blight disease
management. 相似文献
198.
The effect of impact force when using inclined water jets on splittable bicomponents hydroentangled fabrics are investigated
focusing on changes in tensile properties and fiber splitting. The results indicated that with increase of impact force, the
tensile strength was increased in both machine direction (MD) and crosswise direction (CD). On changing of water jet inclination
angle, the tensile strength was the highest at 10 degree followed by 20 degree and the last 0 degree. The highest fiber splitting
were observed in pie segment (PA6/PET) followed by island in sea (PA6/COPET) fiber but no fiber splitting was observed for
island in sea (PET/COPET) fiber. The impact force in inclined mode of impact, played a great role in improving fiber splitting
and tensile properties of hydroentangled nonwoven fabrics. The Scanning Electron Microscope (SEM) photos were used for investigation
of fiber splitting by comparing fiber diameter before and after hydroentanglement. 相似文献
199.
Most multi-purpose water resources have been planned and constructed by governments in Taiwan to meet the water demands of
different users. However, economic and solvency differences among parties using water create conflicts regarding the reasonable
and equitable allocation of investment and operational costs. The Chi-Chi Weir in Nantou County, which was completed in 2002,
meets the high water demand of residents and the needs of industrial growth in central Taiwan. Thus, multi-purpose water reservoirs
are designed to serve agriculture, the public and industry. Three analytical methods, the quantity-based method, marginal
cost method, and separable cost remaining benefit method (SCRB), are employed to compare the cost allocation for different
parties using water. The quantity-based method indicates that proportional costs allocated to agriculture, the public, industry
and new irrigated areas are 88.02, 3.63, 7.86, and 0.49%, respectively. Via the marginal cost method, the proportional costs
allocated to agriculture, the public, hydropower, industry and new irrigated areas are 68.44, 2.51, 28.71, and 0.34%, respectively.
The marginal cost price of water is NT$ 2.97 ton−1; industrial use has the highest price. Based on the SCRB method, the proportional costs allocated to agriculture, the public,
hydropower, and new irrigated areas are 18.2, 22.2, 51.8, 4.8, and 2.9%, respectively. 相似文献
200.
Luciana Linhares de Azevedo Bittencourt Kelly Alencar Silva Valéria Pereira de Sousa Gizele Cardoso Fontes-Sant’Ana Maria Helena Rocha-Leão 《Plant foods for human nutrition (Dordrecht, Netherlands)》2018,73(4):278-286
In the processing of fruits such as blueberry (Vaccinium sp), that has high levels of phenolic acid, the food industry produces tons of organic waste that causes harm to the environment. Encapsulation is a technique used to take advantage of these wastes. Several methods are used to encapsulate substances, among them ionotropic gelation proves to be a simple, precise, efficient and economical method for obtaining particles with encapsulated bioactives. In this manner, the aim of this study was to test sodium alginate as wall material to encapsulate blueberry residue by ionotropic gelation. The microbeads were characterized by scanning electron microscopy (SEM), x-ray diffraction (XRD), total phenolic compounds, antioxidant capacity and in vitro dissolution. The results showed that the microbeads had surface invagination; retention of 67.01% of the phenolic compounds after encapsulation and 68.2%, phenolic release 120 min after in vitro dissolution. The results suggest that the tested matrix was suitable for encapsulation. The produced microbeads are promising for applications in food products, once the phenolic compounds present in the blueberry residues were maintained after encapsulation. 相似文献