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排序方式: 共有484条查询结果,搜索用时 78 毫秒
31.
SHEN Jiamin LIU Shaojun SUN Yuandong ZHANG Chun LUO Kaikun TAO Min ZENG Chen LIU Yun 《自然科学进展(英文版)》2006,16(12):1348-1352
A new type of triploid hybrids (TC) was produced by crossing red crucian carp (♀) with allotetraploid hybrids (♂). This type of triploids with no barbel was spindle-shaped and gray in color. Compared with their parents, some data of the morphological traits in the triploid hybrids were intermediate to those of their parents, and some were beyond their parents with heterozygous traits. Under the same culture conditions, the growth rate of the new type triploids was faster than their maternal red crucian carp (RC). The gonadal development of triploids was obviously slower than that of diploids, and the germ cells in them were degenerated. Compared with another type of triploids produced by Japanese crucian carp (♀) with allotetraploid hybrids (♂), the new type triploids not only kept faster growth rate and sterility, but also had no barbel that was similar to the common carp. The absence of the barbel in the new type of triploids has the important significance in both the inheritance and fish breeding. 相似文献
32.
北极狐绒毛纤维的热学性能研究 总被引:1,自引:0,他引:1
采用热重和差热分析方法测试了北极狐绒毛的热学特征,以及不同温度、时间的热处理对纤维强力、强伸度的影响.实验结果表明,随温度升高北极狐绒毛的TG曲线有两个失重阶,DSC曲线呈现出与羊毛、山羊绒相似的双熔融峰;在热分解温度的前后北极狐绒毛纤维的断裂强力和断裂伸长率呈先上升后下降趋势. 相似文献
33.
In order to obtain union colour on the blends of Tencel and shrink-proofing wool and improve the efficiency of dyeing process, the dyeing behavior on the blends of Tencel and shrink-proofing wool in the same bath was studied. The Argazol TW reactive dyestuffs were involved in the dyeing process. The parameters under different conditions such as exhaustion, fixation, compatibility as well as soaping fastness were investigated in detail. It is shown that the Argazol TW reactive dyestuffs are suitable for dyeing of blends of Tencel and shrink-proofing wool and good dyeing behavior can be expected. 相似文献
34.
IntroductionThemostcommonmethodofyarnproductionistheinsertionofcontinuous ,unidirectionaltwistintoaparallelarrayoffibersorfilaments.Thehightorsionalstressesgeneratedinsuchaprocesshaveaconsiderableeffectonthestabilityandmechanicalcharac teristicsoftheya… 相似文献
35.
在实验基础上探讨了不同纱线捻度。不同编织密度以及不同缩绒温度和缩绒时间的纬平针羊毛衫力学性质的变化规律。通过模糊评价得出编织密度是影响羊毛衫手感的最主要因素,提出了本实验用羊毛衫品种的合理工艺搭配。 相似文献
36.
QTL mapping of the root traits and their correlation analysis with drought resistance using DH lines from paddy and upland rice cross 总被引:8,自引:0,他引:8
MUPing LIZichao LIChunping ZHANGHongliang WUChangming LIChen WANGXiangkun 《科学通报(英文版)》2003,48(24):2718-2724
A Double Haploid (DH) population, 116 plants, derived from the cross between Japonica upland rice IRAT109 and paddy rice Yuefu, planted in PVC pipe under upland ecosystem in 2001 and 2002, was used in this study. Seven root traits, including basal root thickness (BRT), total root number (RN), maximum root length (MRL), root fresh weight (RFW), root dry weight (RDW), ratio of root fresh weight to shoot fresh weight (RFW/SFW) and ratio of root dry weight to shoot dry weight (RDW/SDW), were studied. Using index of drought resistance (IDR), the ratio of yield under upland ecosystem to yield under lowland ecosystem of DH lines, as the criteria of drought resistance, and correla-tion analysis between root traits and IDR, showed that BRT, MRL and RN were significantly correlated with IDR. High IDR lines had thicker BRT, longer MRL and less RN than low IDR lines. A molecular linkage map with 94 RFLP markers and 71 SSR markers covering 1535.1 cM was pro-duced. QTLs and G譋 interactions for BRT, RN, MRL, RFW, RDW, RFW/SFW and RDW/SDW were obtained based on the constructed molecular linkage map and soft-ware QTLmapper version 1.0. A total of 18 additive QTLs and 18 pairs of epistatic QTLs associated with root traits were detected. There were nine additive QTLs and two pairs of epistatic QTLs performed significant interactions with environment. Some QTLs with high general contribution and no G譋 interaction were obtained. Two pairs of epistatic QTLs mrl3 and mrl8, brt3 and brt11a controlling MRL and BRT had high general contributions of 21.51% and 13.03% respectively. An additive QTL and a pair of epistatic QTLs controlling RFW and RDW had high general contributions of 13.50% and 25.64% respectively. Marker assisted selec-tion (MAS) for rice drought resistance based on QTL with high general contribution, low G譋 interaction and tightly linkage with IDR were also discussed. 相似文献
37.
对兔毛纤维采用生物酶处理,使其形态结构发生改变,从而提高了兔毛纤维的表面摩擦系数,增加了纤维之间的抱舍力,提高了纤维的可纺性,改善了兔毛纺织品的脱毛现象. 相似文献
38.
本文研究了羊毛纤维经高温蒸汽及高温水煮处理后的吸湿性能与拉伸性能的变化.采用扫描电子显微镜及X射线衍射仪,分析了羊毛纤维经高温热湿处理后微观结构形态及结晶度.结果表明,经不同温度及时间的蒸汽、水煮处理后,羊毛纤维的吸湿性能出现不规律的变化,而纤维的拉仲强力及伸长则降低;经高温热湿处理后,羊毛纤维的鳞片遭到破坏,纤维结晶指数下降. 相似文献
39.
杨勇 《湖北三峡学院学报》2007,29(3):39-42,98
龄官是《红楼梦》中刻画得比较成功的次要人物之一,她的性格特质是造成其爱情和命运悲剧的重要原因。这一形象具有独特的认知价值和审美内涵,其爱情悲剧在全书整体结构中占有重要地位。 相似文献
40.
于伟东 《东华大学学报(自然科学版)》1998,(5)
毛条染色是经常进行的加工过程,而染色会损伤纤维.及时地检测和给出这种损伤量,十分必要.采用束纤维强伸性测量方法(TENSOR),能快速准确地给出毛条染色前后的强度、伸长、断裂功的护伤.实验结果表明,国内毛条染色的强度损伤在6%~7%,伸长损伤在4%~5%,断裂功损伤在8%~10%.这反映出毛条染色加工中的原毛条质量的浪费. 相似文献