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101.
102.
建筑施工中,沉降观测是监测建筑物是否安全的重要环节,将灰色系统理论应用于建筑物沉降变形的数据分析,结合沉降观测实例,进行沉降预测结果的分析和检验,在一定程度上证实了建筑物沉降变形分析中采用灰色GM(1,1)预测方法的可行性. 相似文献
103.
【目的】估算野生草苺的基因组大小。【方法】以拟南芥(Arabidopsis thaliana)为内标,利用流式细胞仪测定了6个野生草莓种7个待测样品的基因组大小。【结果】6个野生草莓种的基因组大小分别为:黄毛草莓(274±3.80)Mb,五叶草莓(红果类型)(268±3.73)Mb,五叶草莓(白果类型)(258±5.40)Mb,西南草莓(245±3.28)Mb,东北草莓(241±4.28)Mb,森林草莓(231±3.19)Mb,绿色草莓(230±2.83)Mb。【结论】野生草莓基因组大小的测定为草莓属植物基因组文库的建立及其基因组进化等研究提供了基础数据。 相似文献
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105.
Inheritance and Correlation of Self-Compatibility and other Yield Components in the Apricot Hybrid F1 Populations 总被引:2,自引:0,他引:2
Xuesen Chen Yan Wu Meixia Chen Tianming He Jianrong Feng Qing Liang Wen Liu Honghua Yang Lijie Zhang 《Euphytica》2006,150(1-2):69-74
Summary To provide genetic basis for apricot (Prunus armeniaca Lam.) breeding, inheritance and correlation of yield components including self-compatibility, self-pollinated fruiting rate, fertile flower rate, average fruit weight and fruit number per plant were studied with 5-year-old seedlings of apricot F1 hybrids from ‘Katy’ × (‘Xinshiji’, ‘Katy’ × (‘Hongfeng’ and ‘Katy’ × (‘Taianshuixing’, respectively. Using the criteria that cultivars with self-pollinated fruiting rate ≥6% were self-compatible(SC), we found that the ratios of self-compatible (SC) to self-incompatible (SI) individuals were 27:25, 9:12 and 15:19 in the above three families, respectively, and conformed to the ratio of 1:1 segregation by χ2 test, indicating that the S-locus of ‘Katy’ was heterozygous and self-compatibility was dominant to self-incompatibility. Twenty-seven seedlings from the F1 population of ‘Katy’ × ‘Xinshiji’ were chosen for S-allele-specific PCR. As a result, four S-genotypes with the ratio of 10:6:4:7 were obtained, which was linear to the 1:1:1:1 ratio by χ2 test. Great differences in self-compatibility degree were observed among seedlings even with the same S-genotype. In the F1 populations, a very extensive segregation in self-pollinated fruiting rate, fertile flower rate and average fruit weight was observed, and average values of these traits were lower than that of mid-parent. Therefore, these traits were confirmed to be quantitative. However, significant differences were found in broad heritability (H
b
2) of following three characters: the H
b
2 of self-pollinated fruiting rate (87.1% – 91.4%) was the greatest, with the variation mainly resulted from inheritance; fertile flower rate (36.8% – 49.1%) was the least and its variation was mainly caused by environmental factors. In addition, self-pollinated fruiting rate and fertile flower rate had very significantly positive correlations with single plant yield, so both may play important roles in the determination of single plant yield. In contrast, correlation between yield and average fruit weight was not significant. 相似文献
106.
土壤速效养分空间变异研究 总被引:34,自引:4,他引:34
选择山西省一年两作和一年一作两种种植制度下的两个自然村作为试点,通过网格方法采取土样,应用土壤养分系统研究法进行了养分分析,并应用传统统计学和半方差函数对土壤养分变异进行了研究。结果表明,不同种植制度下,土壤养分性质均存在着空间变异,受农业传统施肥措施影响较大的N、P和OM,变异相对较大;而Ca、Mg、K、Cu、Fe、Mn等养分,传统施肥投入较少,土壤变异相对较小;土壤养分性质存在半方差结构,拟合模型包括球型、线型和指数型,但同一养分拟合半方差模型不尽相同。即使模型一致,最大相关距离也不一样,而且空间变异性强弱程度也不尽相同。Ca、N、Mn显示有较强的空间相关性,K、P、S显示具有中等的空间相关性。 相似文献
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108.
以中国古典园林的分类为基点,分析古典园林的特点,总结了中国古典园林的设计手法,提出将其造园手法运用于现代园林的方法和措施,为我国现代园林设计提供一定的理论帮助和参考依据. 相似文献
109.
用溶液培养的方法 ,研究了光照、以及氮水平对不同氮效率玉米自交系根系形态养分吸收的影响 ,研究结果表明 ,提高光照水平有助于光合产物向根系分配 ,表现为总根长、根体积、根系重量等显著增加。在不同光照水平低氮胁迫时 ,氮低效品种白瓷与其它三个品种相比 ,根系的形态指标均有不同程度的降低。在高光强 ,0 .4 mmol/ L氮水平胁迫时 ,与氮高效品种 4 78相比 ,根系体积减少 2 7.54% ,根干重减少 2 1.2 4 % ,并降低了根系的吸收效率 ,同时也表明 ,光照与氮水平对光合产物的分配具有耦合效应 相似文献
110.
Dielectric barrier discharge (DBD) can produce homogenous discharge in normal temperature and atomsphere with low energy consumption, so it has broad development prospects in industrial applications. An experimental study is carried out to optimize the needles arrangement and supply parameters aiming at the multineedle-to-cylinder reactor with orthogonal design in combination with Lissajous figures. As it is konwn, the process of discharge is also the process of charge transfer; hence, the more charges are transported, the higher reaction efficiency in plasma is. The orthogonal design is established with transported charges as the goal factor, and supply voltage, supply frequency, needles length(NL), interneedle rotation angles(INRA) as factors. Variance analysis results show that the largest influence factor is supply voltage, followed by supply frequency; the electrode configuration of NL=(3.5+2) mm and INRA=45° matched with f=21 kHz makes transported charges per cycle biggest. The orthogonal experiment results are verified by further experiments, which is significant to improve the DBD plasma reaction efficiency. 相似文献