该文运用二元决策图(B inary D ecision D iagram)分析传统的静态故障树,运用Markov链分析新兴的动态故障树,由此形成一种创新性的故障诊断方法:综合故障树(Integrated Fau lt Tree)分析法。综合故障树分析法运用分而治之的策略处理各...该文运用二元决策图(B inary D ecision D iagram)分析传统的静态故障树,运用Markov链分析新兴的动态故障树,由此形成一种创新性的故障诊断方法:综合故障树(Integrated Fau lt Tree)分析法。综合故障树分析法运用分而治之的策略处理各种故障,不仅加深了故障诊断、分析的精度,同时也拓展了故障树分析法的运用领域。该文结合实例,运用综合故障树分析法解决容错计算机系统中动态时序特性的建模困难问题;分析结果表明,在容错计算机系统中运用此方法,可以有效地对系统建模和分析系统可靠性。展开更多
The photocatalytic degradation of norfloxacin by bismuth tungstate(Bi2WO6)with different hierarchical architectures wasinvestigated under visible light irradiation.Bi2WO6was prepared by hydrothermal method with the re...The photocatalytic degradation of norfloxacin by bismuth tungstate(Bi2WO6)with different hierarchical architectures wasinvestigated under visible light irradiation.Bi2WO6was prepared by hydrothermal method with the reaction solution pH rangingfrom4to11.The relatively ultrathin Bi2WO6nanoflakes prepared at pH4showed excellent adsorption and photodegradationefficiency towards norfloxacin.The characterization results showed that Bi2WO6prepared at pH4had a larger specific area andfaster photo-generated carrier separation rate.The decay rate reached the maximum in weak alkaline reaction solution,which couldbe attributed to the presence of moderate OH-anions.The present study demonstrated that the smaller size of Bi2WO6could be anefficient photocatalyst on the degradation of norfloxacin in the aquatic environment.展开更多
文摘该文运用二元决策图(B inary D ecision D iagram)分析传统的静态故障树,运用Markov链分析新兴的动态故障树,由此形成一种创新性的故障诊断方法:综合故障树(Integrated Fau lt Tree)分析法。综合故障树分析法运用分而治之的策略处理各种故障,不仅加深了故障诊断、分析的精度,同时也拓展了故障树分析法的运用领域。该文结合实例,运用综合故障树分析法解决容错计算机系统中动态时序特性的建模困难问题;分析结果表明,在容错计算机系统中运用此方法,可以有效地对系统建模和分析系统可靠性。
文摘采用高效液相色谱质谱法分析了湘江长沙河段水体及底泥中4种常见四环素类抗生素的含量特征及其季节变化,并采用实时荧光定量 PCR 研究了该水域相应的5种代表性抗生素抗性基因(tet A,tet C,tet G,tet M 和 tet X)的存在及丰度.结果表明,水体中四环素类抗生素的质量浓度均值在16.23~496.73 ng·L^-1之间,底泥中四环素类抗生素的质量分数为347.77~3829.75 ng·kg^-1,易受季节变化影响.5种目标抗性基因在所有样品中均有检出,其中 tet A 和 tet C 的绝对拷贝数及相对丰度较高,为湘江长沙河段的优势抗性基因.相关性分析表明:冬季水体中的 tet A 和 tet C 含量与底泥中的含量显著相关,几种目标抗生素与抗性基因之间并不存在明显线性关系.
基金Projects(51579096,51222805,51521006,51508175) supported by the National Natural Science Foundation of ChinaProject supported by the National Program for Support of Top-Notch Young Professionals of China+1 种基金Project(NCET–11–0129) supported by the Program for New Century Excellent Talents in University from the Ministry of Education of ChinaProject(CX2015B095) supported by the Hunan Province Innovation Foundation for Postgraduate,China
文摘The photocatalytic degradation of norfloxacin by bismuth tungstate(Bi2WO6)with different hierarchical architectures wasinvestigated under visible light irradiation.Bi2WO6was prepared by hydrothermal method with the reaction solution pH rangingfrom4to11.The relatively ultrathin Bi2WO6nanoflakes prepared at pH4showed excellent adsorption and photodegradationefficiency towards norfloxacin.The characterization results showed that Bi2WO6prepared at pH4had a larger specific area andfaster photo-generated carrier separation rate.The decay rate reached the maximum in weak alkaline reaction solution,which couldbe attributed to the presence of moderate OH-anions.The present study demonstrated that the smaller size of Bi2WO6could be anefficient photocatalyst on the degradation of norfloxacin in the aquatic environment.