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681.
682.
粉尘云最小点火温度测试实验系统设计   总被引:2,自引:0,他引:2  
通过对Godbert -Greenwald恒温炉分析与改造 ,设计了粉尘云最小点火温度实验装置 ,并建立了相应的测试系统。调试结果表明 ,该实验系统扬尘均匀性、温控精度及结果可重复性能良好  相似文献   
683.
It has previously been shown that the level of Daphnia proteins detected by commonly used anti-HSP antibodies, with molecular weights corresponding to those of heat shock proteins, can be modified by various kinds of stress, including the threat of predation. In this study, we demonstrate for the first time that these proteins change their expression in response to thermal stress. Thus, it is concluded that Daphnia heat shock proteins, as components of the cellular stress defense, are involved in both, abiotic and biotic stress.  相似文献   
684.
本文主要探讨了化学防护服(CPC)的功能性测试过程,包括耐化学性能测试、整体性能测试、物理性能测试、人体工程学性能测试。评价CPC是否合格的前题是应该将它暴露在最糟糕的环境下,看它是否能够长时间的起到保护作用。化学防护中与暴露物体直接接触的特征决定了这一类服饰必须经过非常严格的测试才能被选择使用。由此可见性能测试的实用性,对于服装性能测试原理和过程的深刻理解有助于我们了解服装整体的防护性能,更好地做出选择。  相似文献   
685.
大部分煤矿都不程度的受到承压水的影响,承压水的突出绝大多数与断层有直接的关系。以山西某矿承压水体上煤层开采为背景,分析了断层带突水的影响因素及突水机理;通过对矿区水文地质的综合评价,对矿区潜在威胁的断层建立离散元数值模型,进行流固耦合数值分析,以探究邻近构造带底板岩层的应力分布特点及破裂和渗流特征。通过计算表明,随着工作面逐步开采邻近断层,底板破裂深度增大,沿断层面两侧岩体发生滑移错动并伴随渗流发生。  相似文献   
686.
仿真系统已成为工业锅炉操作人员培训的重要手段之一,在工业锅炉仿真系统中加入节能模块,能有效增强经济运行指导和提高操作人员节能意识。本文利用仿真开发平台SimuWorks构建工业锅炉仿真系统节能模块,通过锅炉正反平衡热效率公式分析及简化,给出了飞灰含碳量的直接计算方法,结合各模块计算数据,可以获得完整的运行经济指标。  相似文献   
687.
张波  曾文茹 《火灾科学》2014,23(4):233-237
合成并表征了石墨烯,然后通过溶剂法制备石墨烯/环氧树脂复合材料,研究了石墨烯对环氧树脂复合材料的热稳定性和燃烧性能的影响。热重分析数据显示,石墨烯可以显著提高环氧树脂的热稳定性。锥形量热仪测试结果表明,石墨烯降低了环氧复合材料热和烟气的释放。炭渣的扫描电镜(SEM)图揭示了石墨烯减少了环氧树脂炭层孔洞的生成,提高了炭层的致密度,从而增强了炭层的阻隔作用。  相似文献   
688.
Temperature-programmed pyrolysis mass spectrometry and Fourier-transform infrared spectroscopy have been used to monitor structural changes of humic and fulvic acids isolated from soils in China, in the temperature range of 25-550°C. in this work, we found that decarboxylation is obvious as the main reaction with dehydration reaction from 150°C to 400°C, the anhydride can be identified from FT-IR spectra at temperature range from 200°C to 400°C; there are evident changes of the aromatic nucleus of humic and fulvic acids above 400°C, even remaining up to 550°C. Besides, some changes of adsorption water can be distinguished before 200°C, and the mass signal of sulphur dioxide was detected.  相似文献   
689.
The lethal effects of aluminum ion (Al3+) in tilapia (Oreochromis niloticus) raised in concrete tanks were investigated. Tilapias were fed daily with commercial feed enriched with known concentrations of Al3+ and analyzed by differential pulse anodic stripping voltammetry (DPASV). The concentrations of Al3+ in feces, water, muscle tissue, viscera, and heads were determined every 3 months for a period of 365 days. The Tilapia head was the most affected tissue by Al3+. In general, Al3+ bioaccumulation reached the lethal dose (LD50) after 335 days of experiment as follows: 34.9?mg?kg?1 (muscle tissue), 88.2?mg?kg?1 (viscera), and 126.9?mg?kg?1 (head without gills). After determining Cu2+, Zn2+, and Ca2+ by absorption spectrometry, a decrease in the Ca2+ concentration was noted in the head during the experimental period. These observations were associated with the occurrence of a decalcification in the bone tissue in the presence of Al3+. In contrast, it was found that Zn2+ ions may act as a protective agent against Al3+-induced contamination.  相似文献   
690.
The metabolic fate of ethion labeled with 14C-at the ethyl ester groups in soybean seeds following topical application to leaves was studied. Chromatographic analysis of soybean oil revealed the presence of the parent compound together with four metabolites which were identified as ethion monooxon, ethion dioxon, O-ethyl phosphorothioate and O,O-diethyl phosphorothioate. The effect of processing on ethion residues in soybean oil was investigated. The refined oil contained small amounts of the 14C-residues originally present (37.5%). Upon feeding rats with the cake containing ethion bound residues, a substantial amount of 14C-residues was eliminated in the urine (73%), and about 6% excreted with the feces. About 5% of the radioactive residues were distributed among various organs. Mature male Wistar rats were fed on soybean seeds containing ethion residues (1.93 ppm), and on artichoke leaves powder (1% W/W) for four weeks. At the end of the experimental period, the ethion-treated group had a significantly higher alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) activity, urea, creatinine, total cholesterol (TC), triglycerides (TG), and very low density lipoprotein (VLDL) levels. The ethion-treated rats also had a lower total serum protein and albumin levels, as well as acetyl cholinesterase (AChE), catalase (CAT), and glutathione-S-transferase (GST) activity as compared with controls. Moreover, concomitant treatment with artichoke leaf powder improved, at least partially, all the biochemical parameters that were altered by ethion.  相似文献   
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