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771.
目的研究不同制氧装置和供氧方式对装备人员工效的综合影响。方法从不同吸氧方式对高海拔地区装备人员生理、心理、体能和作业效率等方面的改善效果进行研究。结果吸氧后装备人员的血氧饱和度上升到12%左右、心率减缓10%,体力提高5%左右,工作效率提高13%左右。结论高海拔地区吸氧可以提高从总体上提高装备人员的作业能力,长时间持续低浓度吸氧比间隔式高浓度吸氧对人员的生理、体能和工作效率的改善效果更好。  相似文献   
772.
环境作用动力学基础及应用   总被引:2,自引:2,他引:0  
封先河 《装备环境工程》2015,12(2):15-18,74
目的优化原有的环境作用动力学理论模型。方法在原有环境作用动力学理论模型的基础上,提出环境适应性、环境响应性、变化重复性等3个概念,修改蠕变动力学理论模型的假设2。结果形成了由8个定义、2个假设组成的更加完善的环境作用动力学理论模型。结论新的环境作用动力学理论模型涵盖了蠕变动力学理论模型和原有的环境作用动力学理论模型,应用范围得到大大扩展。  相似文献   
773.
Ultrasonication (US), which creates hydro-mechanical shear forces in cavitation, is an advanced technology in sludge pretreatment. However, there are many factors affecting the efficacy of cavitation and ultrasonication disintegration of sludge as a consequence. The objective of this work is to present an extensive review of evaluation approaches of sludge US pretreatment efficiency. Besides, optimization methodologies of related parameters, the differences of optimum values and the similarities of affecting trends on cavitation and sludge pretreatment efficiency were specifically pointed out, including ambient conditions, ultrasonic properties, and sludge characteristics. The research is a prerequisite for optimization of sludge US pretreatment efficiency in lab-scale and practical application. There is not-yet a comprehensive method to evaluate the efficiency of sludge US pretreatment, but some main parameters commonly used for this purpose are degree of sludge disintegration, proteins, particle size reduction, etc. Regarding US parameters, power input PUS, intensity IUS, and frequency FS seem to have significant effects. However, the magnitude of the effect of PUS and probe size in terms of IUS has not been clearly detailed. Investigating very low FS seems interesting but has not yet been taken into consideration. In addition, static pressure effect has been marginally studied only and investigation on the effect of pH prior to US process has been restricted. Their effects therefore should be varied separately and simultaneously with other related parameters, i.e. process conditions, ultrasonic properties, and sludge characteristics, to optimize sludge US pretreatment process.  相似文献   
774.
Flower-, wire-, and sheet-like MnO2-deposited diatomites have been prepared using a hydrothermal method with Mn(Ac)2, KMnO4 and/or MnSO4 as Mn source and diatomite as support. Physical properties of the materials were characterized by means of numerous analytical techniques, and their behaviors in the adsorption of chromium(VI) were evaluated. It is shown that the MnO2-deposited diatomite samples with different morphologies possessed high surface areas and abundant surface hydroxyl groups (especially the wire-like MnO2/diatomite sample). The wire-like MnO2/diatomite sample showed the best performance in the removal of Cr(VI), giving the maximum Cr(VI) adsorption capacity of 101 mg/g.  相似文献   
775.
Flower-, wire-, and sheet-like MnO2-deposited diatomites have been prepared using a hydrothermal method with Mn(Ac)2, KMnO4 and/or MnSO4 as Mn source and diatomite as support. Physical properties of the materials were characterized by means of numerous analytical techniques, and their behaviors in the adsorption of chromium(VI) were evaluated. It is shown that the MnO2-deposited diatomite samples with different morphologies possessed high surface areas and abundant surface hydroxyl groups (especially the wire-like MnO2/diatomite sample). Thewire-like MnO2/diatomite sample showed the best performance in the removal of Cr(VI), giving the maximum Cr(VI) adsorption capacity of 101 mg/g.  相似文献   
776.
A novel ferruginous active absorbent, prepared by fly ash, industrial lime and the additive Fe(VI), was introduced for synchronous abatement of binary mixtures of SO2–NOx from simulated coal-fired flue gas. The synergistic action of various factors on the absorption of SO2 and NOx was investigated. The results show that a strong synergistic effect exists between Fe(VI) dose and reaction temperature for the desulfurization. It was observed that in the denitration process, the synergy of Fe(VI) dose and Ca/(S + N) had the most significant impact on the removal of NO, followed by the synergy of Fe(VI) and reaction temperature, and then the synergy of reaction temperature and flue gas humidity. A scanning electron microscope(SEM) and an accessory X-ray energy spectrometer(EDS)were used to observe the surface characteristics of the raw and spent absorbent as well as fly ash. A reaction mechanism was proposed based on chemical analysis of sulfur and nitrogen species concentrations in the spent absorbent. The Gibbs free energy, equilibrium constants and partial pressures of the SO2–NOx binary system were determined by thermodynamics.  相似文献   
777.
随着工业化和城市化进程的加快,环境污染问题已成为生态文明建设亟需解决的重要问题.生态文明是对农业文明和工业文明的超越,代表了更为高级的人类文明形态.生态文明建设是体现经济、社会、环境可持续发展以及人与自然和谐共存的重要战略决策.本文从环境质量改善及污染控制的有效性方面,深入剖析了技术创新、产业升级与污染控制之间的互作效应关系,并探讨了有效的实现方式.研究结果旨在为生态文明建设的有效实施和顺利展开提供借鉴和参考价值.  相似文献   
778.
宝安区域污水处理厂出水水质基本是执行城镇污水处理厂污染物排放标准(GB 18918-2002)中一级B标准,需进行深度处理才能再生回用.以固戍污水处理厂为例,分析了实施固戍污水处理厂再生回用水工程的必要性,论证了再生回用水水质、规模和工艺方案,介绍了工程实施后的实际效果.论证的结果表明,采用二级处理加混凝、沉淀、过滤、消毒工艺,来改造宝安区域内的污水处理厂尾水成为再生回用水切实可行.  相似文献   
779.
丁香蓼对Cu富集效应的研究   总被引:1,自引:0,他引:1  
通过盆栽实验研究不同浓度的Cu胁迫对丁香蓼响应和富集效应的影响,结果表明,随着Cu的浓度增加,丁香蓼的株高和生物量降低,长势减弱,但在低浓度(ω(Cu)为125 mg/kg)时降低不明显,与对照组差异性不显著,高浓度与对照组差异性显著。根茎叶中Cu含量随着添加的Cu浓度增加而增加,Cu的含量和富集系数都表现为根叶茎,对Cu的积累量表现为根、茎叶,丁香蓼不是Cu的超富集植物,但对Cu具有较好富集作用和忍耐能力。  相似文献   
780.
双甘膦废水中含有高浓度总磷、有机磷、甲醛、氰化物、氨氮、COD,运用三效蒸发+强氧化+两级化学除磷+UASB+兼氧+好氧组合处理双甘膦废水。研究结果表明双甘膦废水排放满足《污水综合排放标准》(G88978—1996)二级排放标准。  相似文献   
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