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991.
Azohydroxypyridone disperse dyes containing a fluorosulfonyl group were dyed on PET/cotton blends and their dyeing and fastness
properties were investigated. Specially, the azohydroxypyridone dyes containing a nitro group in place of the fluorosulfonyl
group in the para position to azo group were synthesized in order to compare their dyeing and fastness properties on PET/cotton blends with
those of fluorosulfonyl-substituted analogues. As these dyes can be alkali cleared in the same bath, a one-bath dyeing method
was used and the results were compared with that of a conventional two-bath dyeing method. In particular, the cross-staining
of cotton was studied in order to assess their suitability for the one-bath dyeing of PET/cotton blends. 相似文献
992.
Jong Shin Park Yong-Chan Chung Sang Do Lee Jae Whan Cho Byoung Chul Chun 《Fibers and Polymers》2008,9(6):661-666
The shape memory polyurethane (PU) copolymers cross-linked by celite, a porous inorganic material with enormous surface area
and hydroxyl groups on the surface, were prepared to see if the shape memory effect and the mechanical properties were improved.
The PU copolymers with different celite contents were compared and characterized by IR, DSC, DMA, and UTM. The melting temperatures
of PU soft segment were around 20 oC independent of celite content. The shape memory effect and mechanical properties were
dependent on the celite content, and the celite addition into the reaction mixture should be made in the middle of polymerization
to get the best shape memory and mechanical properties. The best mechanical properties were found at 0.2 wt% celite content
and its shape retention rate went up to 98 %. The inclusion of celite as a cross-linker increased both shape memory effect
and mechanical properties. The reasons underlining the improvements by adopting celite as a cross-linker are discussed in
this paper. 相似文献
993.
Park IK Choi KS Kim DH Choi IH Kim LS Bak WC Choi JW Shin SC 《Pest management science》2006,62(8):723-728
Plant essential oils from 40 plant species were tested for their insecticidal activities against larvae of Lycoriella ingénue (Dufour) using a fumigation bioassay. Good insecticidal activity against larvae of L. ingenua was achieved with essential oils of Chenopodium ambrosioides L., Eucalyptus globulus Labill, Eucalyptus smithii RT Baker, horseradish, anise and garlic at 10 and 5 microL L(-1) air. Horseradish, anise and garlic oils showed the most potent insecticidal activities among the plant essential oils. At 1.25 microL L(-1), horseradish, anise and garlic oils caused 100, 93.3 and 13.3% mortality, but at 0.625 microL L(-1) air this decreased to 3.3, 0 and 0% respectively. Analysis by gas chromatography-mass spectrometry led to the identification of one major compound from horseradish, and three each from anise and garlic oils. These seven compounds and m-anisaldehyde and o-anisaldehyde, two positional isomers of p-anisaldehyde, were tested individually for their insecticidal activities against larvae of L. ingenua. Allyl isothiocyanate was the most toxic, followed by trans-anethole, diallyl disulfide and p-anisaldehyde with LC(50) values of 0.15, 0.20, 0.87 and 1.47 microL L(-1) respectively. 相似文献
994.
ABSTRACT Isolates of wheat leaf rust collected from durum and bread wheat cultivars in France during 1999-2002 were analyzed for virulence on 18 Thatcher lines with single genes for leaf rust resistance (Lr genes). Sampling focused on the five most widely grown bread wheat cultivars (two susceptible and three resistant) to allow statistical comparison of diversity indexes between the cultivars. Leaf rust populations from durum and bread wheats were different. The diversity of the bread wheat leaf rust pathotypes, as measured by the Shannon index, ranged from 2.43 to 2.76 over the 4 years. Diversity for wheat leaf rust resistance was limited in the host since we postulated only seven seedling resistance genes in the 35 cultivars most widely grown during 1999-2002. Leaf rust populations were strongly differentiated for virulence within bread wheat cultivars, and diversity was higher on those that were resistant, mainly due to a more even distribution of virulence phenotypes than on susceptible cultivars. The pathogen population on the susceptible cv. Soissons was largely dominated by a single pathotype (073100), whereas all other pathotypes virulent on cv. Soissons either decreased in frequency or remained at a low frequency during the period studied. Several pathotypes including the most complex one were found only on resistant cultivars, even though most of them were virulent on the susceptible cv. Soissons. Specific interactions were necessary, but not always sufficient, to account for pathotype distribution and frequencies on the cultivars, suggesting that selection for virulence to host resistance genes is balanced by other selective forces including selection for aggressiveness. 相似文献
995.
Marker-assisted selection of common beans for resistance to common bacterial blight: efficacy and economics 总被引:11,自引:1,他引:10
The possibility of using random amplified polymorphic DNA (RAPD) markers previously mapped in the common bean PC50/XANI59 population to select for resistance to common bacterial blight (CBB) in different populations was examined. Two out of 02 selected RAPD markers were polymorphic in HR56 and W0633d, the parental lines used in this experiment. Cosegregation analysis of the two polymorphic markers and disease reaction in a recombinant inbred (RI) population derived from HR67/W1744d confirmed that one of the two RAPD markers, BC420900, was significantly associated with a major quantitative trait locus‐conditioning resistance to CBB in HR67. This locus accounted for approximately 51) of the phenotypic variation. The RAPD marker was transformed into a sequence characterized amplified region (SCAR) marker and used for selection in a different population derived from ‘Envoy’/HR67. Prediction for resistance to CBB with the BC420.990 SCAR marker was 94.2% accurate in this population. A comparison between marker‐assisted selection (MAS) and conventional greenhouse screening showed that the cost of MAS is about one‐third less than that of the greenhouse test. 相似文献
996.
Park HR Ahn HJ Kim JH Yook HS Kim S Lee CH Byun MW 《Journal of agricultural and food chemistry》2004,52(9):2572-2576
Lipid oxidation and color stability of meats treated with irradiated phytic acid were investigated during storage for 2 weeks at 4 degrees C. The phytic acid in deionized distilled water (DDW) was degraded by irradiation at 10 and 20 kGy, and the irradiated phytic acid showed a strong antiradical activity. For measuring the antioxidant effects of irradiated phytic acid in food models, beef and pork were prepared with DDW (control), irradiated (10 and 20 kGy) or non-irradiated phytic acid, and ascorbic acid as a model system. Irradiated phytic acid significantly inhibited the lipid oxidation in meats compared to the control and ascorbic acid treated samples during storage (P < 0.05). The redness of the meats treated with phytic acid had a higher value than did the control and ascorbic acid treated samples, but a significant difference was not observed in the samples treated with phytic acid regardless of irradiation treatment. Irradiated phytic acid was also effective in inhibiting the loss of heme iron and metmyoglobin formation during storage. Results indicated that irradiation might be helpful for improving the antioxidant activity of phytic acid in meats. 相似文献
997.
998.
试验旨在测定运用油副产品的有效方法。该油副产品来自红花籽油中共轭亚油酸(CLA)的纯化过程,其中的共轭亚油酸为甘油酯形式。共轭亚油酸副产品(CBP)添加到产蛋鸡饲粮中,以提高共轭亚油酸在卵黄中的积累。试验设3种不同饲粮,分别为:对照饲粮,添加共轭亚油酸副产品2%的饲粮,添加共轭亚油酸-80(含80%游离型共轭亚油酸)2%的饲粮。从3个不同饲粮组获取卵黄,通过气相色谱法分析卵黄脂肪酸,测定蛋品质。在饲养试验阶段,试验组蛋品质和产蛋量几乎没有变化,各试验组间也没有显著差异。添加共轭亚油酸副产品的试验组,在饲养第1周,卵黄中共轭亚油酸含量显著增加;在整个饲养试验阶段,与其他试验组相比,其卵黄中共轭亚油酸含量最高。而添加共轭亚油酸-80试验组,卵黄中共轭亚油酸含量在第3周增加。此外,热处理48h后,共轭亚油酸-80和共轭亚油酸副产品中,总共轭亚油酸异构体含量分别被降低12.92%和0.51%;亚油酸-80(含80%游离型亚油酸)和亚油酸副产品中,亚油酸(LA)异构体含量分别被降低19.63%和5.78%。试验证实共轭亚油酸副产品中脂肪主要是酯化形式,然而共轭亚油酸-80和亚油酸-80中的脂肪由游离脂肪酸构成。油副产品对蛋品质和产蛋量没有影响,作为动物性功能食品来源应用是很有意义的。 相似文献
999.
Hoskins RA Carlson JW Kennedy C Acevedo D Evans-Holm M Frise E Wan KH Park S Mendez-Lago M Rossi F Villasante A Dimitri P Karpen GH Celniker SE 《Science (New York, N.Y.)》2007,316(5831):1625-1628
Genome sequences for most metazoans and plants are incomplete because of the presence of repeated DNA in the heterochromatin. The heterochromatic regions of Drosophila melanogaster contain 20 million bases (Mb) of sequence amenable to mapping, sequence assembly, and finishing. We describe the generation of 15 Mb of finished or improved heterochromatic sequence with the use of available clone resources and assembly methods. We also constructed a bacterial artificial chromosome-based physical map that spans 13 Mb of the pericentromeric heterochromatin and a cytogenetic map that positions 11 Mb in specific chromosomal locations. We have approached a complete assembly and mapping of the nonsatellite component of Drosophila heterochromatin. The strategy we describe is also applicable to generating substantially more information about heterochromatin in other species, including humans. 相似文献
1000.
James M. Myers Linda K. Park Kathleen G. Neely Penny Swanson Anna E. Elz Jeffrey J. Hard 《Journal of the World Aquaculture Society》2011,42(6):812-823
We assessed the effects of different feeding regimes on reproductive traits in coho salmon, Oncorhynchus kisutch. Ration treatments subjected fish to different energy levels during oocyte proliferation (Year 1) and oocyte maturation (Year 2). Fish from 10 full‐sibling families were fed at either the recommended feeding rate or double the recommended ration during the first year. At the beginning of the second year, each ration group was split again into recommended and double ration tanks for a total of four dietary treatments. At the end of the second year, 365 females from the four treatment groups were spawned and body weight, egg weight, and egg number were measured. Overall, the fish fed the double ration during both years grew the fastest (50.1% larger than controls), had the highest egg number (46.3% larger), and had the largest eggs (9.6% larger), although similar increases were observed feeding at the double ration level during the second year alone. Ration modification produced significant changes in some reproductive traits, especially egg number, while family effects had a greater influence on relative fecundity (eggs/g female body weight) and egg weight. In fact, family effects were significant for all of the traits. Results indicate that reproductive traits can be manipulated through changes in ration and/or via genetic selection, either directly or indirectly. 相似文献