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201.
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
202.
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
203.
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
204.
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
205.
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
206.
Chromophore incorporated into the protein chains through residue modification on silk fibroin will be an important way to get new dyeing technology with improved color fastness. Herein, 1-aminoanthraquinone diazonium salt was prepared and used for the modified dyeing on tyrosine of silk fibroin. The silk after modified dyeing was measured by UV-Vis, FTIR, MS, 1H-NMR, Data color, and other testing techniques. Interestingly, the resulting silk showed excellent rub and wash fastness. The enhanced color fastness is contributed by an electrophilic substitution reaction between 1- aminoanthraquinone diazonium salt and the ortho position of phenolic hydroxyl in tyrosine molecular. Moreover, the mechanical property of silk was protected effectively by the mild coupling modified dyeing, better than the traditional acid dyeing under high temperature for a long time. This facile strategy provides an alternative approach to silk dyeing and benefits the silk applications. 相似文献
207.
Mochamad Asrofi Hairul Abral Anwar Kasim Adjar Pratoto Melbi Mahardika Ji-Won Park Hyun-Joong Kim 《Fibers and Polymers》2018,19(8):1618-1625
The successful isolation and characterization of water hyacinth fiber (Eichornia crassipes) (WHF) nanocellulose is presented in this study. The novelty was in exploring a wider range of properties of highly purified samples of WHF after each stage of production in more depth. The isolation was accomplished by pulping in a digester and sonication. Morphological changes before and after treatment were demonstrated by scanning electron microscopy (SEM). The lignin and hemicellulose content decreased during chemical treatment. Transmission electron microscopy (TEM) and particle size analyzer (PSA) were used to determine the morphology of WHF after sonication for 1 h. TEM shows that the diameter and length of nanocellulose WHF were 15.61 and 147.4 nm, respectively. The crystallinity index and crystalline domain area significantly increased after chemical treatment. The highest crystallinity index was 84.87 % after an acid hydrolysis process. The increase in crystallinity leads to good thermal stability. Moisture absorption tests of WHF were carried out before and after treatment. The lowest moisture absorption was in the cellulose fiber after sonication (nanocellulose). 相似文献
208.
Background
Knowledge bases that summarize the published literature provide useful online references for specific areas of systems-level biology that are not otherwise supported by large-scale databases. In the field of neuroanatomy, groups of small focused teams have constructed medium size knowledge bases to summarize the literature describing tract-tracing experiments in several species. Despite years of collation and curation, these databases only provide partial coverage of the available published literature. Given that the scientists reading these papers must all generate the interpretations that would normally be entered into such a system, we attempt here to provide general-purpose annotation tools to make it easy for members of the community to contribute to the task of data collation.Results
In this paper, we describe an open-source, freely available knowledge management system called 'NeuroScholar' that allows straightforward structured markup of the PDF files according to a well-designed schema to capture the essential details of this class of experiment. Although, the example worked through in this paper is quite specific to neuroanatomical connectivity, the design is freely extensible and could conceivably be used to construct local knowledge bases for other experiment types. Knowledge representations of the experiment are also directly linked to the contributing textual fragments from the original research article. Through the use of this system, not only could members of the community contribute to the collation task, but input data can be gathered for automated approaches to permit knowledge acquisition through the use of Natural Language Processing (NLP).Conclusion
We present a functional, working tool to permit users to populate knowledge bases for neuroanatomical connectivity data from the literature through the use of structured questionnaires. This system is open-source, fully functional and available for download from [1].209.
Frank Havemann Michael Heinz Hildrun Kretschmer 《Journal of Biomedical Discovery and Collaboration》2006,1(1):6
Background
The hypothesis that distance matters but that in recent years geographical proximity has become less important for research collaboration was tested. We have chosen a sample–authors at German immunological institutes–that is relatively homogeneous with regard to research field, language and culture, which beside distance are other possible factors influencing the willingness to co-operate. We analyse yearly distributions of co-authorship links between institutes and compare them with the yearly distributions of distances of all institutes producing papers in journals indexed in the Science Citation Index, editions 1992 till 2002. We weight both types of distributions properly with paper numbers.Results
One interesting result is that place matters but if a researcher has to leave the home town to find a collaborator distance does not matter any longer. This result holds for all years considered, but is statistically most significant in 2002. The tendency to leave the own town for collaborators has slightly increased in the sample. In addition, yearly productivity distributions of institutes have been found to be lognormal.Conclusion
The Internet did not change much the collaboration patterns between German immunological institutes.210.
Proyuth Ly Quynh Duong Vu Lars Stoumann Jensen Arjun Pandey Andreas de Neergaard 《Paddy and Water Environment》2015,13(4):465-475
We studied the effects of water regimes and nutrient amendments on CH4 and N2O emissions in a 2 × 3 factorial, completely randomised growth chamber experiment. Treatments included continuously flooded (CF) and alternate wetting and drying (AWD), and three organic amendments: no amendment-control, rice straw (RS) and biochar (BC). Compound fertiliser was applied to all treatments. Rice was grown in columns packed with a paddy soil from Cambodia. Results revealed faster mineralisation of organic carbon (RS and BC) when applied in water-saturated conditions lasting for 2 weeks instead of flooding. This resulted in lower total CH4 emissions in treatments under AWD than those under the CF water regime, namely 44 % in RS treatments and 29 % in BC treatments. Nitrous oxide fluxes were generally non-detectable during the experimental period except after fertilisation events, and the total N2O–N emissions accounted for on average 1.7 % of the total applied mineral fertiliser N. Overall, the global warming potentials (GWPs) were lower in treatments under AWD than those under the CF water regime except for the control treatment with only mineral fertiliser application. Grain yields were slightly higher in treatments under AWD than the CF water regime. Hence, the yield-scaled GWP was also lower in the treatments under the AWD water regime, namely 51 % in RS, 59 % in BC and 17 % in control treatments. Control treatments had the lowest GWP, but provided the highest yield. The yield-scaled GWP under these treatments was therefore lower than under the other treatments. 相似文献