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121.
122.
本文重要介绍用于电气运行人员培训的动态仿真专家系统的设计思想、实现方法及其应用效果。  相似文献   
123.
Oxygen evolution reaction (OER) plays a pivotal role in the development of renewable energy methods, such as water-splitting devices and the use of Zn–air batteries. First-row transition metal complexes are promising catalyst candidates due to their excellent electrocatalytic performance, rich abundance, and cheap price. Metalloporphyrins are a class of representative high-efficiency complex catalysts owing to their structural and functional characteristics. However, OER based on porphyrin systems previously have been paid little attention in comparison to the well-described oxygen reduction reaction (ORR), hydrogen evolution reaction, and CO2 reduction reaction. Recently, porphyrin-based systems, including both small molecules and porous polymers for electrochemical OER, are emerging. Accordingly, this review summarizes the recent advances of porphyrin-based systems for electrochemical OER. Firstly, the electrochemical OER for water oxidation is discussed, which shows various methodologies to achieve catalysis from homogeneous to heterogeneous processes. Subsequently, the porphyrin-based catalytic systems for bifunctional oxygen electrocatalysis including both OER and ORR are demonstrated. Finally, the future development of porphyrin-based catalytic systems for electrochemical OER is briefly prospected.  相似文献   
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A growing body of research suggests that inflammatory insult contributes to the etiology of central nervous system diseases, such as depression, Alzheimer’s disease, and so forth. However, the effect of prenatal systemic inflammation exposure on offspring brain development and cerebral susceptibility to inflammatory insult remains unknown. In this study, we utilized the prenatal inflammatory insult model in vivo and the neuronal damage model in vitro. The results obtained show that prenatal maternal inflammation exacerbates LPS-induced memory impairment, neuronal necrosis, brain inflammatory response, and significantly increases protein expressions of COX-2, DP2, APP, and Aβ, while obviously decreasing that of DP1 and the exploratory behaviors of offspring rats. Meloxicam significantly inhibited memory impairment, neuronal necrosis, oxidative stress, and inflammatory response, and down-regulated the expressions of APP, Aβ, COX-2, and DP2, whereas significantly increased exploring behaviors and the expression of DP1 in vivo. Collectively, these findings suggested that maternal inflammation could cause offspring suffering from inflammatory and behavioral disorders and increase the susceptibility of offspring to cerebral pathological factors, accompanied by COX-2/PGD-2/DPs pathway activation, which could be ameliorated significantly by COX-2 inhibitor meloxicam treatment.  相似文献   
126.
郭春信  尧勇  李刻铭 《暖通空调》2007,37(2):71-75,37
介绍了柴油发电机组的几种换热方式与发热量的构成。强调了采用通风降温时,换热器的热风不能排入机房,应直接排入排风道,再由耐高温风机排至室外。通过实例说明了这种降温方式最小进排风量的计算方法。介绍了目前工程中存在的几个共性问题,并提出了解决方法。  相似文献   
127.
谭曜  王群威  崔家玲 《广东化工》2008,35(1):104-106
聚氯乙烯树脂稀溶液粘数是聚氯乙烯树脂的一项重要指标,它的高低决定着产品的不同用途。本实验测试了几种不同测试条件如测试温度、黏度计毛细管直径、溶剂浓度等对聚氯乙烯树脂稀溶液粘数结果所产生的影响,通过实验数据的理论分析和计算,对原因进行了具体的分析。这些分析结果的获得对提高粘数分析的准确性,对于指导实际生产,规范检验操作,修订检验标准都有着重要的意义。  相似文献   
128.
Heterotrimeric guanine nucleotide binding protein (G-protein) consisting of Gα, Gβ, and Gγ subunits is one of the key signal transducers in plants. Recent studies indicated that G-protein has been proposed as an important mediator of nitrogen responses in rice, wheat, and Arabidopsis. However, little is known about these G-proteins in Brassica napus (B. napus), except for three identified G-proteins, BnGA1, BnGB1, and BnGG2. Therefore, the aim of the present study is to characterize the members of the G-protein gene family in allotetraploid B. napus and to analyze their expression profiles in response to nitrogen deprivation. In total, 21 G-protein family members were identified in B. napus, encoding two Gα, six Gβ, and 13 Gγ. Sequence and phylogenetic analyses showed that although genome-wide triploid events increased the number of genes encoding Gα, Gβ, and Gγ subunits, the gene structure and protein properties of the genes encoding each G-protein subunit were extremely conserved. Collinearity analysis showed that most G-protein genes in B. napus had syntenic relationships with G-protein members of Arabidopsis, Brassica rape (B. rapa), and Brassica oleracea (B. oleracea). Expression profile analysis indicated that Gα and C-type Gγ genes (except BnGG10 and BnGG12 were highly expressed in flower and ovule) were barely expressed in most organs, whereas most Gβ and A-type Gγ genes tended to be highly expressed in most organs. G-protein genes also showed various expression patterns in response to nitrogen-deficient conditions. Under nitrogen deficiency, Gα and five C-type Gγ genes were upregulated initially in roots, while in leaves, Gα was downregulated initially and five C-type Gγ genes were highly expressed in different times. These results provide a complex genetic dissection of G-protein genes in B. napus, and insight into the biological functions of G-protein genes in response to nitrogen deficiency.  相似文献   
129.
基于模糊层次分析法的隧道施工安全评价方法   总被引:3,自引:0,他引:3  
利用模糊数学和层次分析法构建了公路隧道施工系统安全综合评价模型,该模型在评价过程中不仅使主观与客观相统一,而且能够模拟人对复杂决策问题的思维判断过程,并对一些难以避免的模糊概念用量化来表示,得到的评价结果比较直观.通过工程应用,验证了该评价方法切实可行.  相似文献   
130.
本文根据4年多的研究成果,分析了用水文学法研究水土流失问题的可行性,介绍了水文学法研究水土流失的方法步骤,并与经验公式法研究成果进行对比,以供参考.  相似文献   
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