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61.
62.
针对现阶段土壤中重金属污染较为严重的问题及各类修复方法各有利弊的现状,分析了近年来相关学者对于改良剂对重金属污染根际土壤理化性质影响的研究进展,研究了常见有机和无机改良剂对重金属胁迫下根际土壤pH值、氧化还原电位(Eh)、酶活性、化学性质、微生物菌落种群等理化性质的影响以及对重金属的化学沉淀和溶解平衡的影响。后期应加强超富集植物与一般植物根际、非根际理化性质的差异研究;土壤中重金属种类及污染程度与根际土壤理化性质的关系研究;土壤中其他环境因子的影响以及根际土壤中重金属的作用机理方面的研究。 相似文献
63.
Amanda Broska da Cruz Deniz Renata Bachmann Guimarães Valt Maria José Jerônimo de Santana Ponte Haroldo de Araújo Ponte 《化学工程与技术》2020,43(7):1393-1401
Transport phenomena are investigated which are involved in the electrokinetic remediation process used for removing vanadium from deactivated catalysts from oil catalytic cracking that are currently allotted to cement plants and class-I landfills. Variables such as the concentration of electrolyte, electric potential, and applied electric current were evaluated in order to determine the effects produced by electroosmosis, diffusion, hydraulic gradient, and electromigration on the removal of vanadium from the catalyst. It was observed that migration is the most relevant phenomenon in the remediation tests, and for the best remediation condition, the migratory flow accounted for about 87 % of the vanadium removal. 相似文献
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65.
Julio Flores-Gonzalez Juan Carlos Cancino-Díaz Leslie Chavez-Galan 《International journal of molecular sciences》2020,21(22)
Recent advances in the field of flow cytometry (FCM) have highlighted the importance of incorporating it as a basic analysis tool in laboratories. FCM not only allows the identification of cell subpopulations by detecting the expression of molecules in the cell membrane or cytoplasm, but it can also quantify and identify soluble molecules. The proper functioning of the FCM requires six fundamental systems, from those related to the transport of events to the systems dedicated to the analysis of information. In this review, we have identified the main considerations that every FCM user must know for an optimal antibody panel design, the quality systems that must govern the FCM protocols to guarantee reproducible results in research or clinical laboratories. Finally, we have introduced the current evidence that highlights the relevance of FCM in the investigation and clinical diagnosis of respiratory diseases, establishing important advances in the basic and clinical study of diseases as old as Tuberculosis along with the recent proposals for the monitoring and classification of patients infected with the new SARS-CoV2 virus. 相似文献
66.
根据自动化生产线分拣站的工艺流程和自动化控制的要求,提出基于工业机器人、PLC以及传送带的货物码垛自动化解决方案。构建以三菱FX3U型PLC、传送带和工业机器人等组成的全自动分拣码垛系统。分析了PLC的动作过程,提供了PLC的程序流程图;分析了工业机器人码垛的工作过程,提供了工业机器人码垛的程序流程图。工业机器人引入到自动化生产系统后,能够进一步提高工厂自动化水平、提高生产效率,减小劳动强度,降低人工成本。 相似文献
67.
Ricardo Martínez-Corona Gerardo Vázquez Marrufo Carlos Cortés Penagos Luis Alberto Madrigal-Pérez Juan Carlos González-Hernández 《Yeast (Chichester, England)》2020,37(1):149-162
Lipases are hydrolytic enzymes that break the ester bonds of triglycerides, generating free fatty acids and glycerol. Extracellular lipase activity has been reported for the nonconventional yeast Kluyveromyces marxianus, grown in olive oil as a substrate, and the presence of at least eight putative lipases has been detected in its genome. However, to date, there is no experimental evidence on the physiological role of the putative lipases nor their structural and catalytic properties. In this study, a bioinformatic analysis of the genes of the putative lipases from K. marxianus L-2029 was performed, particularly identifying and characterizing the extracellular expected enzymes, due to their biotechnological relevance. The amino acid sequence of 10 putative lipases, obtained by in silico translation, ranged between 389 and 773 amino acids. Two of the analysed putative proteins showed a signal peptide, 25 and 33 amino acids long for KmYJR107Wp and KmLIP3p, and a molecular weight of 44.53 and 58.23 kDa, respectively. The amino acid alignment of KmLIP3p and KmYJR107Wp with the crystallized lipases from a patatin and the YlLip2 lipase from Yarrowia lipolytica, respectively, revealed the presence of the hydrolase characteristic motifs. From the 3D models of putative extracellular K. marxianus L-2029 lipases, the conserved pentapeptide of each was determined, being GTSMG for KmLIP3p and GHSLG for KmYJR107Wp; besides, the genes of these two enzymes (LIP3 and YJR107W) are apparently regulated by oleate response elements. The phylogenetic analysis of all K. marxianus lipases revealed evolutionary affinities with lipases from abH15.03, abH23.01, and abH23.02 families. 相似文献
68.
69.
设计一种基于人机接触力的人体主动参与程度评估模型,用于康复机器人应用中的主动康复训练。通过人体的肌电信号得到肌肉活跃度,确定肌电信号与人体参与度的关系。分析这一过程中人机接触力的变化,将腿部力信号平均值以及腰部力信号方差作为模型输入,对基于肌电信号的参与度模型进行拟合,得到基于力信号的参与度模型,使用肌电信号参与度模型对力信号参与度模型进行验证,证明了该模型的有效性。该方法避免了肌电信号采集时干扰较大且准备工作繁琐等缺点,具有良好的实用性。 相似文献