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71.
Lili Zhao Linlin Xue Binbin Li Qingling Wang Baokun Li Shiling Lu Qinglu Fan 《International Journal of Food Science & Technology》2018,53(10):2256-2264
This study assessed the effect of ferulic acid on the accumulation of histamine in traditional Xinjiang smoked horsemeat sausage. The dynamics of histamine‐producing microorganisms were monitored by PCR‐denaturing gradient gel electrophoresis (DGGE) with specific primer pairs, and histidine and histamine levels were measured by high‐performance liquid chromatography (HPLC). Relative parameters including microbiological growth, pH and moisture content were also evaluated. PCR‐DGGE provided a rapid and convenient method for detecting and identifying histamine‐producing bacteria. The results showed that ferulic acid reduced the histamine concentration and inhibited the growth of histamine‐producing bacteria during fermentation and ripening. Additionally, the inhibitory effect of ferulic acid was stronger than that of the starter culture. Therefore, ferulic acid appears to be a useful additive for manufacturing fermented sausages. 相似文献
72.
Comparative study of iron-based Fischer–Tropsch synthesis catalyst promoted with potassium or sodium
《Catalysis communications》2008,9(12):1957-1962
FeCu/SiO2 catalysts, in which K or Na promoter is incorporated respectively, are prepared by a combination method of continuous co-precipitation and spray drying technology. The catalysts were characterized by temperature-programmed desorption and Mössbauer spectroscopy. The Fischer–Tropsch synthesis (FTS) performance of the catalysts was studied in a continuously stirred tank slurry reactor. The basicity of the K-promoted catalyst is enhanced, as demonstrated by CO2-TPD results. MES results show that sodium can weaken the dispersion of α-Fe2O3 phase; either potassium or sodium can promote carburization of the catalyst, while the effect of sodium is weaker. FTS results indicate that the addition of K or Na can improve the catalyst activity, and shift the product distribution to heavy hydrocarbons to the different extent. 相似文献
73.
In order to effectively allocate the idle spectrum and improve spectrum utilization of cognitive wireless sensor networks, it is necessary to design an efficient spectrum allocation algorithm. Aiming at the problem of spectrum allocation in cognitive wireless sensor networks, an improved method for spectrum allocation is suggested. A new chaotic dynamic clonal evolution algorithm is designed. Then the graph theory coloring model is established with the corresponding fitness function derived. Traditional evolutionary algorithms have the problem of premature convergence, so chaotic operators, adaptive operators and cloning operators are added to the traditional evolutionary algorithms to accelerate the convergence of the algorithm. The chaotic dynamic clonal evolutionary algorithm is compared with the simulated annealing algorithm and the ant colony algorithm by simulation. The simulation results show that compared with the ant colony algorithm and the simulated annealing algorithm, the chaotic dynamic clonal evolution algorithm can effectively improve the global search ability, and significantly improve the network benefit value of spectrum allocation. The results also show that the proposed chaotic dynamic clonal evolution algorithm can make full use of existing spectrum resources and improve the system throughput. 相似文献
74.
水利枢纽工程可以实现对水资源的统一调配, 提高水资源利用率, 改善工程所在地区用水状况.本文以新疆下坂地工程为例,通过探讨其在解决叶尔羌河流域灌区春早补水问题、提供电力补偿和改善生态环境等方面所起到的巨大作用,以及由此带来的经济效益,说明了水利枢纽工程对流域经济的发展有着显著的推动作用. 相似文献
75.
不同负载量对霞多丽葡萄生长发育及酿酒品质的影响 总被引:3,自引:0,他引:3
为探索不同负载量对葡萄及葡萄酒品质的影响,对8年生霞多丽进行了不同负载量试验。结果表明,合理降低负载量能提高葡萄品质,增加果实含糖量,葡萄酒感官品质也显著改善;以留穗数为10穗/株(产量700.3kg/667m2)和15穗/株(产量1028.9kg/667m2)处理较优,负载量过大表现较差。综合分析,霞多丽葡萄的适宜负载量为700~1000kg/667m2。 相似文献
76.
浅谈大学化学教学中的诚信教育 总被引:1,自引:0,他引:1
诚信是中华民族的传统美德,诚信教育是大学生道德建设的永恒主题。诚信教育不但是政治理论课的教学任务,也是自然科学的教学任务,更是像化学这样实践性强的课程的重要教学任务。文章就化学学科的特点、校园环境、教师自身、科学本身探讨了大学生的诚信教育。 相似文献
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78.
地基处理课程涉及的知识体系庞杂,是系列岩土课程群的总结课程之一。在厘清地基处理课程体系特点的基础上,提出了适合地基处理自身特点的教学思路及其实践教学改革方法,为今后地基处理课程教材的编写及课堂教学提供借鉴。 相似文献
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