油棕叶梗重组方材制备工艺

以油棕叶梗为原材料、酚醛树脂为胶黏剂，采用正交试验方法研究重组方材密度、施胶量、热压时间和热压温度对油棕叶梗重组方材力学性能的影响。结果表明，密度对油棕叶梗重组方材性能的影响较大，密度和施胶量越大，重组方材力学性能越好；热压温度和热压时间对油棕叶梗重组方材性能的影响比较复杂。综合考虑确定油棕叶梗重组方材的较优制备工艺条件为:密度0.7 g/cm³，施胶量12%，热压温度180℃，热压时间40 min；较优工艺条件下油棕叶梗重组方材的弹性模量为7 185 MPa，静曲强度为68.7 MPa，顺纹抗压强度为35 MPa，内结合强度为0.21 MPa。密度为0.7 g/cm³的油棕叶梗重组方材的弹性模量、静曲强度、顺纹抗压强度高于了杉木的性能。     

Nitrogen fertilization affects yields and storage compound contents in seeds of field-grown soybeans cv Enrei (Glycine max. L) and its super-nodulating mutant En-b0-1 through changing N2 fixation activity of the plants

ABSTRACT

We compared the protein and oil contents, seed yields, and natural abundance of ¹⁵N (σ¹⁵N) of seeds from the plants of the cultivar Enrei, which has moderate nodulating ability (Enrei) with those of its two near-isogenic lines (NILs), a super-nodulating genotype of Enrei, i.e., En-b0-1, and a non-nodulating genotype of Enrei, i.e., En1282. Plants of these three genotypes were grown on four types of field plots with different types of urea coated slow-release nitrogen (N) fertilizers (CUSLNFs) which delivered N in different manners during plant growth . The seed yield of the En1282 plants was similar to that of the Enrei plants but much greater than that of the En-b0-1 plants when the plants were grown on the field to which a CUSLNF with a long lifespan was applied. The amounts of protein per seed were positively correlated with those of oil per seed in the case of En1282 plants irrespective of the field N conditions. The seed protein contents were proportional to the seed weight in both En1282 and Enrei plants. Such a relationship was not observed in the En-b0-1 plants, and the protein and oil contents in the seeds of En-b0-1 plants were negatively correlated with each other. These observations suggested that the N supply to maturing seeds was a key to the protein contents in the En1282 and Enrei plants and that the C supply to maturing seeds was a key to the protein contents in the En-b0-1 plants. The comparison of the σ¹⁵N values, protein contents, and seed yields of seeds from En1282 plants suggested that the Enrei plants assimilated considerable amounts of N from the soil during the late plant growth. We concluded that high N₂ fixation activity depressed the amounts of oil per seed and changed the protein and oil contents in soybean seeds.     

茉莉花香气成分及其加工应用研究进展

笔者阐述了茉莉花香气成分的释放机理,分析了影响茉莉花香气成分的因素,指出茉莉花香气成分的释放主要是酶促反应的进行,是由花香前体物质在温度、水分、氧气等作用下经生物酶水解释放出来,认为品种、花的开放程度、产地、环境因子、提取方法都对茉莉花香气成分的组成和含量具有不同程度的影响,其中以花的开放程度、环境因子和提取方法最为明显。文章还对茉莉花在食品、茶叶、香烟及其他方面的应用做了概述,最后对茉莉花的理论研究以及开发新产品方面做了展望。     

火灾环境下邻近罐壁热辐射分布实验

油罐火灾蔓延的主要因素是油罐热辐射,在着火罐火焰热辐射作用下,邻近罐极易被引燃,造成整个罐区大面积起火。为了研究邻近罐罐壁热辐射分布规律,建立了油罐燃烧对邻近罐热辐射影响的小尺寸实验装置,开展了火灾环境下邻近罐壁热辐射分布的实验研究。结果表明:在火灾环境下,邻近罐正对着火罐方向的罐壁受辐射作用最大,热辐射从罐顶到罐底逐渐降低、从中心向两边呈轴对称降低;随着L/D(L为相邻两个油罐的距离,D为油罐的直径)增大,邻近罐热辐射下降。实验数据为火灾环境下邻近罐的热辐射研究提供了参考,对防止邻近罐被引燃,做好油罐区火灾爆炸事故的预防具有重大意义。     

美国油气管道基本失效概率评估方法及启示

为充分利用油气管道历史失效数据,减少失效概率评估过程中的主观性,提出油气管道基本失效概率的概念及评估方法。对美国管道及危险物品安全管理局数据库的油气管道里程数据、事故数据及失效因素数据进行全面分析,采用基于事故统计的方法评估油气管道基本失效概率。结果表明:美国危险液体管道、输气集气管道、配气管道发生一般事故的基本失效概率分别为1.29次/(10^3 km·a)、2.17次/(10^4 km·a)及4.08次/(10^5 km·a),发生较大事故的基本失效概率分别为4.58次/(10^4 km·a)、1.41次/(10^4 km·a)及2.38次/(10^5 km·a),发生重大事故的基本失效概率分别为9.09次/(10^6 km·a)、9.79次/(10^6 km·a)及1.11次/(10^5 km·a)。美国基本失效概率可作为油气管道失效概率评估的基准线,也可作为风险可接受标准的依据,但不能直接应用于中国管道风险评价,需对其进行修正,建立适用于中国管道的失效数据库。     

黑豆—油菜与大豆—油菜轮作模式土壤镉修复能力比较

通过设置黑豆-油菜、大豆-油菜的轮作模式在湖南醴陵进行大田试验,结果发现黑豆表现出较强的镉富集能力,其根、茎、叶及果壳中镉含量分别为2.14、2.63、4.10及1.34 mg/kg,富集系数均在1以上。油菜各个部位镉含量较高的分别为叶与茎,达到了7.13和4.73 mg/kg。黑豆各部位镉转运系数均高于大豆,各油料作物提取的重金属主要集中在茎与叶。大豆叶的镉富集系数为2.06,茎的镉富集系数为0.86,明显低于黑豆同部位的富集能力。每公顷土地经过一轮黑豆-油菜、大豆-油菜轮作分别能够从土壤中提取73.52 g和51.68 g的镉,对土壤重金属镉的修复效率约为3%。     

关于中国智慧管道发展的认识与思考

智慧管道是覆盖油气长输管道全生命周期的综合管理系统,是SCADA系统、电子管道、数字管道、智能管道在物联网、云计算、人工智能时代的延续和发展。剖析了油气管道行业智慧管道的内涵与外延,梳理了智慧管道技术发展的历史脉络,揭示了数字孪生体技术的实质与应用现状,在此基础上,建议中国智慧管道建设宜坚持需求驱动、问题导向、突出重点、体现特色、开放融合、数据共享、滚动发展、持续改进的原则,以期为中国智慧管道的健康持续发展提供参考。     

油料作物油脂合成调控研究进展

植物油脂不仅是人类可食用油的主要来源,也是人类生产生活中重要的可再生原料。本文概述了植物油脂的生物合成途径,从母体效应、QTL、GWAS等多个方面总结了油料作物油脂合成的遗传学研究进展,同时探讨了已知的油脂合成调控相关基因的功能。本文综述了该领域的研究现状,为深入了解油料作物油脂合成调控网络提供了参考,也为油料作物的分子改良和遗传育种提供了理论基础。     

In vitro susceptibility of Brachyspira hyodysenteriae to organic acids and essential oil components

The antibacterial potential of organic acids and essential oil components against Brachyspira hyodysenteriae, the causative pathogen of swine dysentery, was evaluated. Minimum inhibitory concentrations (MIC) of 15 compounds were determined at pH 7.2 and pH 6.0, using a broth microdilution assay. In addition, possible synergism was determined. MIC values for the three tested strains were similar. For organic acids, MIC values at pH 6.0 were lower than at pH 7.2. B. hyodysenteriae was most sensitive to cinnamaldehyde and lauric acid, with MIC values <1.5 mM. Most antibacterial effects of binary combinations were additive, however, for thymol and carvacrol, synergism could be observed. In vitro results demonstrate the antibacterial action of certain essential oil components and organic acids against B. hyodysenteriae.