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991.
张新建 《中州煤炭》2020,(2):14-19,24
针对煤矿“双重预防体系”如何落地生根问题,结合陈四楼煤矿在风险分级管控和隐患排查治理方面的实用方法和“双重预防体系”的建设经验,深入研究了“双重预防体系”的相关标准、风险隐患事故之间的关系及其各自的产生和发展机理、安全风险的有关辨识评估方法、事故隐患的排查和治理方法,分析了传统安全管理模式与“双重预防体系”的新型安全管理模式的差别,总结出了“123456双重预防体系”这个囊括了事前安全风险辨识、事中隐患排查治理、事后安全现状评估的创新成果,实现了“事前、事中、事后”的全过程控制,对夯实煤矿安全管理根基、促进矿井平稳有序发展发挥着越来越重要的作用,为煤炭行业“双重预防体系”的落地生根提供了借鉴和参考。  相似文献   
992.
Phorbol 12-myristate 13-acetate (PMA) is a potent tumor promoter and highly inflammatory in nature. Here, we investigated the toxic effects of PMA on different model system. PMA (10 μg) caused chromosomal aberrations on the Allium cepa root tip and induced mitotic dysfunction. Similarly, PMA caused embryonic and larval deformities and a plummeted survivability rate on zebrafish embryo in a dose-dependent manner. Persistently, PMA treatment on immortalized human keratinocyte human keratinocyte (HaCaT) cells caused massive inflammatory rush at 4 h and a drop in cell survivability at 24 h. Concomitantly, we replicated a cutaneous inflammation similar to human psoriasis induced by PMA. Herein, we used tangeretin (TAN), as an antagonist to counteract the inflammatory response. Results from an in vivo experiment indicated that TAN (10 and 30 mg/kg) significantly inhibited PMA stimulated epidermal hyperplasia and intra-epidermal neutrophilic abscesses. In addition, its treatment effectively neutralized PMA induced elevated reactive oxygen species (ROS) generation on in vitro and in vivo systems, promoting antioxidant response. The association of hypoxia-inducible factor 1-alpha (HIF-1α)-nuclear factor kappa-light-chain-enhancer of activated b cells (NF-κB) crosstalk triggered by PMA enhanced PKCα-ERK1/2-NF-κB pathway; its activation was also significantly counteracted after TAN treatment. Conclusively, we demonstrated TAN inhibited the nuclear translocation of HIF-1α and NF-κB p65. Collectively, TAN treatment ameliorated PMA incited malignant inflammatory response by remodeling the cutaneous microenvironment.  相似文献   
993.
电化学阻抗谱技术能够获取燃料电池不同频率阻抗,但对阻抗的构成缺乏进一步解析,难以直接构建精准的等效电路模型进行阻抗拟合分析,而弛豫时间分布(Distribution of relaxation time,DRT)方法不需要定义特定的等效电路模型,即可解析燃料电池不同时间常数的极化过程。针对实验室用质子交换膜燃料电池,在不同运行条件下对其进行阻抗谱测量,并通过Kramers-Kronig关系验证所记录阻抗数据的质量。基于DRT分析方法,系统地解释阻抗谱中各频段阻抗对应的物理或化学意义。研究表明,该电池的电化学阻抗谱主要由3个不同时间常数频段的极化阻抗构成,通过与运行条件相关性的系统分析,确定低频段阻抗为氧气在多孔介质中的传输阻碍,中频段阻抗为与氧还原反应有关的电荷传递阻碍,中高频段阻抗为阴极催化剂层中的质子传输阻碍。为进一步确定DRT分析结果的合理性,采用等效电路模型拟合测量的阻抗数据,辨识的电阻元件参数变化趋势与DRT分析结果一致。  相似文献   
994.
基于某款磁流变减振器特性实验数据,辨识了磁流变减振器魔术公式模型的各项参数,模型误差在8%以内。在适当简化磁流变减振器魔术公式模型的条件下,通过直接逆推得到磁流变减振器魔术公式逆模型。仿真中,磁流变减振器魔术公式正、逆模型实现加速度驱动阻尼控制策略期望阻尼力的误差平均值为3.67%。台架实验中,磁流变减振器魔术公式逆模型的应用使车身加速度降低了6.27%,实现了加速度驱动阻尼控制策略的控制效果。磁流变减振器魔术公式模型在半主动控制悬架系统仿真及台架实验中的成功应用对磁流变半主动悬架控制系统的研究有较强的实际意义。  相似文献   
995.
探讨了制造技术发展趋势,论述了制造历史发展的三个阶段,指出原子及近原子尺度制造(ACSM)是下一代制造技术的主流发展趋势,对未来科技发展和高端元件制造具有重要意义。详细分析阐述了ACSM的主要研究内容及关键科学问题,并提出了相应的建议和措施。  相似文献   
996.
997.
王海明 《轧钢》2018,35(6):84-85
针对热轧除鳞系统普遍存在的能源浪费严重的问题,设计了基于预测模型的变频节能方案,通过板坯位置预测、除鳞时间预测、除鳞水量预测和除鳞泵转速控制,合理利用轧制间歇时间使水泵电机变频降速,模拟计算结果表明,可使除鳞电耗降低23.57%。  相似文献   
998.
The growing demand for stony corals as ornamental aquarium animals requires defined aquacultural breeding strategies. For the sexual propagation of corals, material substrates are needed, that attract larvae and support their settlement and development. In this study, five types of highly porous ceramic materials were developed following the example of coral skeleton. The applicability of these settlement substrates was tested using larvae of the stony coral Pocillopora damicornis. Partial sintering of pressed clay pellets, freeze casting of clay and alumina-mullite based slurries and direct foaming of high alkane phase emulsified suspensions (HAPES) using alumina were employed. By the addition of mm-sized spherical polystyrene beads as sacrificial templates during freeze casting (alumina-mullite), superficial pores in the size of the larvae were created. The inorganic substrates featured open porosities between 35% (pressed clay) and 83% (foamed alumina), pore sizes ranging from nm to mm-scale and pore morphologies dominated by interparticle porosity (pressed), lamellar pores (freeze casting) and cellular pore types (direct foaming). The ceramic substrates were incubated in artificial sea water for 3 months to induce necessary biofilm formation and algae growth. Afterwards, individual substrates were exposed to 5 coral larvae, and their settlement behavior was monitored over 14 days. At the end of this period, all ceramic materials were successfully accepted as settlement substrates, with a mean settlement rate of 46.2%, and no significant differences between the substrate types. On samples with large surface superficial pores, a significantly reduced survival of settled larvae (79%) compared to the other porous materials (93–98%) was determined, suggesting a non-ideal surface topography. While alumina foam samples (HAPES) exhibit the most promising results in terms of settlement and survival of larvae, clay-based substrates provide a more economic solution for the sexual propagation of corals in aquaculture.  相似文献   
999.
This article deals with the evaluation of pressure drop and consumption of energy for a steady-state solvent extraction in a horizontal pulsed sieve-plate column, which are important for the design and optimization of the periodic-flow processes for industrial applications. In this study, the pressure drop and the position of loading points are investigated. Moreover, a mathematical evaluation on the energy consumption in the case of a pulsed flow is conducted, and besides the influence of pulsation intensity, the effect of geometrical parameters including the plate spacing and plate-free area is investigated as well. The results of this study are helpful for optimization of column geometry targeted to higher performance and lower energy consumption.  相似文献   
1000.
Processing lithium-ion battery (LIB) electrode dispersions with water as the solvent during primary drying offers many advantages over N-methylpyrrolidone (NMP). An in-depth analysis of the comparative drying costs of LIB electrodes is discussed for both NMP- and water-based dispersion processing in terms of battery pack $/kWh. Electrode coating manufacturing and capital equipment cost savings are compared for water vs. conventional NMP organic solvent processing. A major finding of this work is that the total electrode manufacturing costs, whether water- or NMP-based, contribute about 8–9% of the total pack cost. However, it was found that up to a 2?×?reduction in electrode processing (drying and solvent recovery) cost can be expected along with a $3–6?M savings in associated plant capital equipment (for a plant producing 100,000 10-kWh Plug-in Hybrid Electric Vehicle (PHEV) batteries) using water as the electrode solvent. This paper shows a different perspective in that the most important benefits of aqueous electrode processing actually revolve around capital equipment savings and environmental stewardship and not processing cost savings.  相似文献   
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