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181.
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青藏高原独特的施工环境,对隧道施工人员、机电设备的效率以及施工保障造成很大困难。文章介绍电脑导向台车用地公路隧道钻眼掘进,以及有关的保障措施,保证台车的正常工作。 相似文献
183.
结合现有的道路交通安全管理体制,提出了道路交通事故黑点治理的流程.在分析了已有的各类交通事故黑点鉴别理论的基础上,指出事故次数法与事故率法在我国现阶段仍具有初步筛选的现实意义.最后,结合日益普及的高速公路路网,分析了此类道路黑点的改造策略. 相似文献
184.
在电动自行车电池使用过程中,需要定期对电池充电以满足用户需求,此文分别对温度与电动自行车电池的材料、容量、寿命、充电电压及存储时间的关系进行研究。结果表明电动自行车电池最宜使用温度为25℃左右,温度过高或过低,都会降低电池使用寿命。 相似文献
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Fungal infection remains a major problem worldwide, yet treatment options are limited owing to the lack of effective drugs, the significant toxicity of available compounds, and the emergence of drug resistance. The low toxicity of calcofluor white (CFW) is an attractive antifungal compound for its known inhibitive effects on trichophyton rubrum and candida albicans growth. However, the efficacy of CFW is limited in most cases. In order to search for effective means to improve its efficacy, using saccharomyces cerevisiae as a model, we have used microarrays to examine the cell's response when treated with CFW on the genome scale. We found that both the PKC-SLT2 (i.e, protein kinase C-mitogen activated protein kinase) and the glycogen metabolic pathways are activated upon CFW treatment. These results suggest that the key components in these pathways could be targeted by other drugs to counter the cell's compensative response, thus to further substantiate the inhibitive effect of CFW on fungal growth, which may lead to treatment regimens with improved efficacy of this compound in clinical applications. 相似文献
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结合桥梁冬季施工中存在的问题,对水泥水化热的影响和混凝土早期受冻的影响等问题进行详细介绍.以贵阳某桥段冬季施工为例,针对所出现的问题采取了材料保温与养护保温的改善措施,可为同类工程提供参考借鉴. 相似文献
190.
Scrap leather fibers (SLFs) modified with active silane containing epoxide groups were incorporated into poly(lactic acid) (PLA) modified by vinyl trimethoxysilane, i.e., the PLA/SLF composites were prepared for bio-composites by solvent compounding technology in this article. The effects of silane coupling agents on the structures of PLA and SLF molecules were examined, and the mechanical properties and thermal stability of PLA/SLF composites were also measured. The results of Fourier-transform infrared spectroscopy (FTIR) had proved that silane had been incorporated successfully to PLA and SLF molecules by means of the solvent technology. Scanning electric microscopy (SEM) was used to investigate both the changes in shapes between the pristine SLFs and the treated SLFs and the microscopic structures of composites. According to SEM results, it was shown that there were some significant differences between the untreated and treated SLFs, and a double continuous phase structure had occurred in PLA/SLF composites due to the excellent dispersion of SLFs in matrix. The addition of the treated SLFs into PLA resulted in a distinct improvement of the impact and tensile strengths. When the mass fraction of the treated SLFs was 15%, the notched impact strength and tensile strength of PLA/SLF bio-composites were improved by 34.4% and 21.2% compared with the pristine PLA, respectively. Additionally, with the increase of the modified SLFs content, the thermal stability of PLA/SLF bi-composites was apparently improved. The macroscopic properties of bio-composites were found to be strongly dependent on their components, concentration, dispersion and resulted morphological structures. 相似文献