斜拉桥拉索锚区箱梁的空间应力分析

采用空间板单元对实际的斜拉桥拉索锚区箱梁段进行了有限元计算，绘出了箱梁中各应力分量，分析了各应力分量的危险区域，为实际桥梁的设计与施工提供了可靠的依据。     

油气输送管道漏磁检测的有限元分析

叙述了电磁场有限元分析的理论基础，给出了油气输送管道漏磁检测中的漏磁场，用ANSYS软件包对具体实例进行了分析，得到了漏磁场的空间分布、磁感应强度及漏磁信号图等。分析结果有助于全面认识空间中漏磁场，可为油气输送管道提供缺陷定量化检测依据。     

气候要素对给排水工程的影响

论述了在给排水工程设计中 ,当地气候要素对给排水工程的影响是重大的 ,它往往是决定工程规模、造价和总体布局等的重要因素     

黄壤茶园土壤有机质与微量元素的含量研究

对四川茶区黄壤中有机质与微量元素的相互关系研究表明,当有机质含量为0.97％至7.0％时,Al、Ca、Zn仝量随之增大,有机质含量为0.9％～15.9％时,土壤仝镁量与有机质呈极显著正相关,茶园土壤中腐殖质总量与Cu、Zn有效量呈极显著正相关。     

原子吸收光谱法测定紫苏属植物叶中的无机元素

采用原子吸收光谱法对紫苏属叶中Fe,Mn,Mg,Zn,Cr,Cu,Cd,Pd,Ca无机元素含量进行了测定。试验结果表明,该属植物叶中均含有丰富的Fe,Mn,Mg,Zn,Cu,Ca元素,但均未检测到Cd,Cr,Pd。除Mg,Mn含量与一般植物相当外,其他各元素的含量均高于常见植物,尤以Ca含量相对较高;该属植物叶中无机元素含量的差异与其具体的原(变)种没有显著关系。     

21世纪桃树次生木质部导管分子特征的观察

运用离析法和显微照相等技术,以晚熟桃21世纪桃为试材、典型的耐寒品种珲春桃为对照,研究比较了21世纪桃次生木质部导管分子的特征。结果表明,21世纪桃树干次生木质部导管分子中存在着许多不同的样式,迎风面导管分子的特征为多具尾性、长导管性、宽导管性、孔纹导管、单穿孔等,这些特征为21世纪桃在生长季节旺盛的水分需求提供了强有力的保证作用,同时,在风力强劲的冬季也可能使导管容易形成空穴和栓塞,水力结构破坏,致使输水系统受限,可能造成冬害。     

枣果营养成分分析及其品质评判

在对陕西省37个土栽、稀有或引进的枣树品种果实的有机营养成分和矿质营养元素含量进行了14个项目的定量分析后,运用灰色关联度分析原理,对各品种枣果的测试数据予以处理运算,并进行灰色评判。将37个品种评判出品质优良、良好、一般和较差四个等级。     

Effect of dietary fish oil on the expression of genes involved in lipid metabolism in liver and skeletal muscle of lactating sows

This study investigated the hypothesis that dietary supplementation of fish oil as a source of n‐3 polyunsaturated fatty acids (PUFA) influences the expression of target genes of sterol regulatory element‐binding proteins (SREBP)‐1 and (SREBP)‐2 involved in triacylglycerol (TAG) synthesis and fatty acid and cholesterol metabolism in the liver, and moreover activates the expression of target genes of peroxisome proliferation‐activated receptor (PPAR)‐α involved in TAG and fatty acid catabolism in liver and skeletal muscle. Twenty lactating sows were fed a control diet or a fish oil diet with either 50 g of a mixture of palm oil and soya bean oil (4:1, w/w) or fish oil per kg. The diet of the fish oil group contained 19.1 g of n‐3 PUFA (mainly 20:5 n‐3 and 22:6 n‐3) per 100 g of total fatty acids, while the diet of the control group contained 2.4 g of n‐3 PUFA (mainly 18:3 n‐3) per 100 g of total fatty acids. The fish oil group had reduced relative mRNA concentrations of various target genes of SREBP‐1 involved in fatty acid and TAG synthesis in comparison with the control group (p < 0.05). Relative mRNA concentrations of target genes of PPARα involved in fatty acid catabolism in both liver and muscle, and mRNA concentrations of target genes of SREBP‐2 involved in cholesterol synthesis and uptake were not influenced by fish oil supplementation. Concentrations of cholesterol and TAG in plasma, fat content of milk and weight gains of litters during the suckling period were not different between the two groups of sows. In conclusion, this study suggests that fish oil has only minor effects on hepatic lipid metabolism, which are non‐critical with respect to milk production in sows.