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1.
采用正交试验法,研究涂饰工艺对木质体育地板表面滑动摩擦系数的影响,试验因素为面漆涂饰次数、涂料种类和面板砂光目数,试验测试指标为表面滑动摩擦系数。方差分析结果表明,涂料种类与测试指标呈极为显著的影响关系,水性面漆涂饰的试件表面滑动摩擦系数相对较高;其他2个因素与测试指标之间无显著影响关系。砂光目数极可能对表面滑动摩擦系数有一定影响,但这一影响关系被底漆涂饰工艺所覆盖,因此所有试件的表面滑动摩擦系数全部达到了国家标准的要求。  相似文献   
2.
Rice appearance trait is mainly mean grain length (GL), grain width (GW), ratio of length and width (L/W), chalkiness (CH) and transparence (TR). Appearance is the first impression, and rice appearance traits effect significantly the value of commodity. Hybrid rice is relatively low quality, especially on rice appearance quality,which restricts partially its extend and badly export of hybrid seed and rice in China.Shanyou 63, the most famous hybrid rice combination of China, could not be also sustainable application because of its poor qualities. In this studies, We attempt to improve appearance quality of the elite rice maintainer of Zhenshan 97B by using molecular approach of genomic interval targeted introgression. Three F2 populations were constructed to study the classical and molecular genetic of rice appearance traits, at the same time, molecular marker-asisted toimprove the main maintainer line, Zhenshan 97B were performed. There some following results:Three F2 populations were constructed based on crosses of Guangluai 4×Jiafuzhan (GJ popu.), Minghui 86×Jiafuzhan (MJ popu.) and Zhenshan 97B×Jiafuzhan (ZJ popu.). ZJ popu and GJ popu were produced to reconstruct the linkage maps related with rice appearance traits based on BSA, and detect QTL of target traits based on IM.In ZJ popu, 9 QTLs of target traits were detected. The interval, RM169~RM516 on Chromosome 5, was genetic locus of GW, L/W, CH and BW, and the explained variances were 10.9%, 14.9%, 12.0% and 14.2%, respectively.RM214 on chromosome 7, RM339 on chromosome 8 were genetic loci if CH and BW, and the explained variances were 9.4%, 10.0%, 11.0% and 12.1%. besides there is a genetic locus, RM347, of G/W on chromosome 3, and the explained varance was 10.3%. In GJ popu, 5 QTLs of rice appearance traits were detected. The interval, RM169-RM516 on Chromosome 5, were also the genetic loci of GW, CH and BW, and the explained variances were 9.0%, 12.5%, and 13.6%, respectively. RM264~RM80 on chromosome 8 was the genetic loci of GW amd L/W,and the explained variances were 14.7% and 13.4%. The genotypes of all QTLs, except RM214, from Jiafuzhan contributed to improving riee appearance traits.The research was to improve the rice appearance quality of Zhenshan 97B by introgressing QTLs of rice appearance traits from Jiafuzhan, a donor parent, by means of MAS in the process of recurrent backcrossing, 4 SSR markers were used to detect the target genotypes from donor parent, and 70 SSR primers to identify the genetic background of recurrent parent. Consequently, there were 19 target individuals in BC3, in which the mean value of GL, GW, L/W, CH and BW were 6.06±0.04mm, 2.50±0.02mm, 2.43±0.02, 29.5±2.7 and 29.4±2.7%, respectively,and the mean homologous degree (HD) to recurrent parent is up to 98.22%. Compared to Zhenshan 97B, GL, CH and BW decreased 0.17 mm, 34.9% and 34.5% respectively and however L/W increased 0.19. which accounted separately for 25.37%, 54.79%, 54.57% and 10.50% of thedifference of every trait between two parents. It is very luckly to find a individual, 13BC2-3BC3 line, whose GL, GW, G/W, CH and BW were 6.04 mm, 2.43 mm, 2.49,2.5% and 2.5% separately, There is very important signification for it to be used in hybrid rice breeding improving appearance traits. In the research, MAS efficiency of 3 loci (with 4 markers ) was 5.68% and coincident degree was 73.08%.  相似文献   
3.
传染性法氏囊病是鸡的最严重疾病之一,其病原是鸡传染性法氏囊病病毒(IBDV),IBDV基因组为两片段双链RNA,变异株和超强毒株的出现,给传统的疫苗免疫带来了新的挑战,因此,加强对IBDV的基础研究是控制该病的关键.RNA的结构不稳定成为阻碍RNA病毒研究的主要障碍,近年来兴起的反向遗传技术将RNA病毒的基因组转化为cDNA,从而使RNA病毒的基因操作成为可能,也使RNA病毒的研究获得了快速的发展.文章就传染性法氏囊病病毒反向遗传操作研究的意义、方法、概况及相关分子生物学进行了全面综述.  相似文献   
4.
秦芋32号(原代号:康0102-5)是2000年以秦芋30号作母本,89-1优系作父本,有性杂交获得实生种子,经育种圃、鉴定圃选育而成。2011年3月申报国家农作物品种审定委员会待审,2011年10月通过审定。2007~2009年参加国家级马铃薯品种中晚熟西南组繁种及区域试验;2010年国家西南组生产试验平均产量1 443 kg/667 m2,比对照米拉增产12.5%。块茎干物质含量18.5%、淀粉含量11.8%,Vc含量14.2 mg/100 g,还原糖含量0.29%,粗蛋白含量2.1%。抗病性接种鉴定:中抗PVX和PVY,抗晚疫病。  相似文献   
5.
茶园滴灌施肥的增产提质及土壤养分效应研究   总被引:2,自引:0,他引:2  
以常规施肥作为对照,设计3个不同氮素用量(450、300、150 kg/hm2),研究了茶园滴灌施肥对茶叶产量、品质及土壤养分性状的影响。结果表明,滴灌施肥处理比对照增产3.4%~9.3%,施氮量与产量间呈明显正相关,以年施氮量300~450 kg/hm2产量较高,滴灌施肥对茶叶品质影响不显著。滴灌施肥处理成熟叶含氮量显著高于对照,且季节性差异明显,秋茶﹥夏茶﹥春茶,滴灌施肥可促进茶树对氮素的吸收利用。施肥方式对土壤pH值影响显著,滴灌施肥处理土壤pH值明显高于对照,可能因其氮素利用率较高而有助于减弱无机氮对土壤的酸化作用。  相似文献   
6.
阐述了室内绿化的发展历程、主要功能以及室内绿化植物应用的种类、布置方式、摆放手法,提出室内绿化植物应用的发展方向与措施.  相似文献   
7.
介绍了中国古代门窗和现代门窗的发展历程,阐明了各时期门窗的特点及发展状况;探讨了古代门窗形制的变化特点、现代门窗用材和制作工艺的发展历程。  相似文献   
8.
IgG(IgY)是鸭卵黄中的唯一免疫球蛋白。根据GenBank发表的鸭的IgG Fc段的核苷酸序列、氨基酸序列,和多种动物进行遗传进化分析。得出鸭与鸡的核苷酸同源性分别为67.9%,与其他所列哺乳动物的核苷酸同源性集中在40%~52%之间。鸭与鸡的氨基酸同源性57.5%,与其他所列哺乳动物的氨基酸同源性集中在34%~43%之间。进化树结果显示鸭的IgG Fc段基因与鸡此段基因具有较近的亲缘关系。  相似文献   
9.
10.
用RT-PCR法获得了涵盖狂犬病病毒Flury LEP株全基因组的3个重叠的cDNA片段,将获得的cDNA片段分别克隆至pMD18-T Simple载体上并进行序列测定,对测序结果进行拼接,得到全长cDNA序列,结果表明,Flury LEP株全长为11 924 bp,3-′UTR长58 bp,编码区核苷酸为11 723 bp,5-′UTR为131 bp。  相似文献   
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