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以抗病品种"青薯168"和易感品种"陇薯3号"马铃薯块茎为试材,比较2个品种马铃薯块茎、切片接种硫色镰刀菌(F.sulphureum)后苯丙烷代谢关键酶活性和相关产物积累的动态变化。结果表明,"青薯168"马铃薯块茎及其切片接种F.sulphureum后的病斑直径显著小于"陇薯3号"。2个品种马铃薯接种F.sulphureum后,在前期苯丙氨酸解氨酶(PAL)、4-香豆酰-辅酶A连接酶(4CL)活性以及总酚、类黄酮含量增加,但随着病斑的扩展,PAL、4CL活性以及总酚、类黄酮含量迅速降低并低于未接菌对照。肉桂酸-4-羟化酶(C4H)活性和木质素含量在整个培养过程中均显著低于未接菌对照。抗病品种"青薯168"接种F.sulphureum后,PAL、4CL和C4H活性以及总酚、类黄酮和木质素含量均显著高于"陇薯3号"。表明苯丙烷代谢在F.sulphureum与马铃薯块茎互作的早期发挥了积极的作用,一旦病斑开始扩展,苯丙烷代谢的抗病作用将显著降低;抗病块茎的苯丙烷代谢活性显著高于感病块茎,表明苯丙烷代谢在马铃薯块茎抗干腐病方面具有重要的作用。 相似文献
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Jie Feng Xiao‐Bei Zhan Zhi‐Yong Zheng Dong Wang Li‐Min Zhang Chi‐Chung Lin 《International Journal of Food Science & Technology》2012,47(10):2072-2078
Effects of novel two‐step inoculation to enhance soy sauce special flavour in Candida etchellsii were investigated at the cell growth phase. The first‐stage consists of a 5% culture inoculum of log phase cells at 30‐day. Subsequently, a 20% culture inoculum of stationary phase cells was added at 60‐day. The resulting amino nitrogen and soluble salt‐free solid yield reached 9.15 ± 0.12 and 269.60 ± 3.15 mg L?1 in 30 °C incubator experiments, increased by 23.1% and 17.6%, respectively, as compared to the control without culture inoculation. Maximal free amino acid yield of 58.21 ± 1.77 g L?1 was achieved, and 39 types of volatile flavour compounds content was 17.81 ± 0.45 g L?1, which were 1.76% and 178.7% higher than the control. A novel two‐step inoculation using the C. etchellsii yeast was developed and optimised. It was proven to be a feasible reproducible process for industrial application for the improvement of the flavour and quality of soy sauce production. 相似文献
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Qiang Liao Ye-Jun Wang Yong-Zhong Wang Rong Chen Xun Zhu Yu-Kang Pu Duu-Jong Lee 《International Journal of Hydrogen Energy》2012
A two-dimensional model is developed to describe the photosynthetic bacteria (PSB) biofilm formation on the solid surface in a flat-panel photobioreactor. The diffusion-reaction equations and cellular automata (CA) rule along with the previously obtained growth kinetics parameters of PSB are used to simulate the coupled mass transport and biochemical reaction as well as the biomass growth. With this model, the effects of the illumination intensity, pH value and initial inoculation on the formed biofilm morphology, porosity, roughness and thickness are investigated. Numerical results show that the biofilm porosity and thickness continuously decreases and increases during the PSB biofilm formation process, respectively, while the surface roughness reaches a stable value after a certain time. The optimal conditions for the PSB biofilm formation are the initial inoculation of 500, and the illumination intensity of 5000 lx and pH value of 7.0. 相似文献
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以大米、糯米、鲜嫩玉米为原料,人工接种苗族农家老酸汤生产发酵型白酸汤。通过对发酵时间、发酵温度、接菌量的研究,确定发酵白酸汤生产工艺的最佳参数。结果表明:以大米、糯米、鲜嫩玉米的混合谷物作为原料(混合比例2:1:1)、老酸汤接种量(体积分数)15%、发酵温度40℃、发酵时间3d,制得的酸汤气味芳香,酸度适口,具有苗族酸汤独特的风味。 相似文献
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介绍了汽车铸件的结构以及技术要求,根据技术要求将球化处理后的化学成分控制在:w(C)3.6%~3.8%,w(Si)2.6%~2.9%,w(Mn)0.25%~0.45,w(P)≤0.030%,w(S)≤0.015%,w(Mg残)0.03%~0.04%,w(RE残)0.01%~0.02%,采用5 t中频炉熔炼,原铁液出炉温度控制在1 480~1 520℃,采用冲入法进行球化处理,选用低RE的FeSiMg6RE2球化剂,粒度为10~25mm,加入量为每包铁液量的1.1%;采用粒度为3~8 mm的CaBa复合孕育剂进行一次孕育,浇注时使用粒度为0.3~1 mm的高CaBa复合孕育剂进行二次随流孕育。最终生产铸件的球化等级控制在2~3级,石墨球大小6级,抗拉强度不低于600MPa,伸长率不低于10%,且珠光体体积分数及力学性能波动均在10%以内。 相似文献
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Liu Jincheng 《中国铸造》2014,(4):339-350
The demands for improved engine performance,fuel economy,durability,and lower emissions provide a continual challenge for engine designers.The use of Compacted Graphite Iron(CGI)has been established for successful high volume series production in the passenger vehicle,commercial vehicle and industrial power sectors over the last decade.The increased demand for CGI engine components provides new opportunities for the cast iron foundry industry to establish efficient and robust CGI volume production processes,in China and globally.The production window range for stable CGI is narrow and constantly moving.Therefore,any one step single addition of magnesium alloy and the inoculant cannot ensure a reliable and consistent production process for complicated CGI engine castings.The present paper introduces the SinterCast thermal analysis process control system that provides for the consistent production of CGI with low nodularity and reduced porosity,without risking the formation of flake graphite.The technology is currently being used in high volume Chinese foundry production.The Chinese foundry industry can develop complicated high demand CGI engine castings with the proper process control technology. 相似文献
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通过对铸铁材料的概述,详细分析了铸件中常见缺陷——缩孔的特征、危害以及形成原因,从而探讨抑制此类缺陷的对策。 相似文献