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活性炭纤维吸附—催化燃烧新装置处理有机废气 总被引:1,自引:0,他引:1
介绍了一种处理有机废气的吸附一催化燃烧新型装置,以活性炭纤维为吸附剂,结合多单元分流组合式吸附床,采用PLC电脑来实现整个系统的连续运行,实际运行结果表明,对于处理大风量、低浓度的有机废气,该技术与其它技术相比具有净化效率高、节能降耗、自动化水平高等优点。 相似文献
243.
氨氮测定时应注意的几个问题 总被引:1,自引:0,他引:1
纳氏试剂比色法是测定水中氨氮的国家标准方法[1].标准方法对氨氮的介绍比较详细,测定步骤也较简单,但实际工作中,情况比较复杂,条件较苛刻,实验空白值难以达到要求(A≤0.030),很多具体的因素都干扰影响该方法的灵敏度,也直接影响分析结果的精密度和准确度.根据多年的实际工作经验,将氨氮测定过程中容易出现的问题及注意事项进行了总结. 相似文献
244.
工业企业噪声环境影响评价中的测点布设与测量、预测时段的选择 总被引:1,自引:0,他引:1
指出工业企业噪声环境影响评价中,由于测点与测量时段选择的不妥,导致测量及预测值“以偏代全”的结果;提出了测点合理布设与测量、预测时段科学选择的原则,以使测量与预测结果能较好地符合项目建成前后噪声环境实际状况。 相似文献
245.
活性污泥PVA膜状固定及净化污水效率 总被引:2,自引:0,他引:2
PVA膜状固定细胞是一种新细胞固定化方法。在加入少量藻酸钙盐的条件下 ,用硼酸交联聚乙烯醇 ( PVA) ,活性污泥培养物渗于其内 ,将其涂于载体上被固定成膜。细胞经固定后仍保持活力 ,PVA—藻酸钙盐珠非常结实耐用。 相似文献
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248.
It is well recognized that a trigger point is a functional, rather than an anatomical, entity. It is known that a significant
fraction of both acute and chronic pain experience is myofascial in nature. This paper is aimed to discuss the potential of
using permanent magnets placed over the trigger points, which are associated with that referred pain, to be a tool for pain
relief. This approach is even more important in patients with various disabilities and experiencing chronic sacro-iliac and/or
low back pain. It appears that the trigger points represent a plausible physiological/tissue “window” and/or pathways, which
allow the magnetic fields to penetrate through physiological barriers, and thus returning injured tissues to the homeostatic
state. These “tissue windows” represent physiological “entrance points” for eventual exogenous stimulations, mainly physical
by nature, to enter the body. There is evidence that the application of magnetic fields (via permanent magnets) on trigger
points is more effective for pain relief as compared to application to other body surface area. The systemic effects at which
the results are manifested at sites distant from application area is also considered when discussing effects of magnetic fields
applied on trigger points. Ion transport is considered as central to the integrity and proper functioning of nerve excitability
and muscle contraction. Any disruption of their normal function would directly and markedly affect human neurosensory and
neuromotor performance. Biophysical phenomena associated with modification of ion transport are in the range of weak stimuli.
Therefore, electrophysiological changes in the functions of the so-called ion channels, are among the more (perhaps the most)
sensitive indicators to detect and quantify physiological effects of electromagnetic fields. 相似文献
249.
A new coal pillars design method in order to enhance safety of the retreat mining in room and pillar mines 总被引:1,自引:0,他引:1
Most of the proposed methods for coal pillar design determine pillar dimensions using pillar load estimation only through the tributary area theory. Designing pillar based on these methods is not appropriate in room and pillar mines with pillar recovery because retreat mining and gob creation generate abutment loads. Neglecting abutment loads in design stage may lead to pillar failure and destructive effects during retreat mining. Thus proper pillar design has a remarkable effect on mining safety. In this paper, a step-by-step method is presented to design pillars with square shape in room and pillar mines with regard to existing pillars in the active mining zone (AMZ) and estimating abutment loads according to experimental equations. A decrease in pillar failure risk during retreat mining is the most significant benefit of this method. This method has been applied to determine optimum pillar dimensions in the main panel of Tabas Central Mine (TCM), located in the mid-eastern part of Iran. Obtained results show the abutment loads account for 27% of the total loads applied on pillars in AMZ in this panel. Pillar width, based on this method, is also obtained 11.6 m. 相似文献
250.
为了研究多米诺效应中多事故点协同作用的后果,将并联系统概率模型运用到贝叶斯概率计算过程中,体现出多事故点协同作用对多米
诺效应传播的概率影响;后果分析部分从人、物、环境3个方面出发,对事故的后果影响以及事故预防提出建议措施。最后运用模型对实例进行
了应用分析,结果表明:多事故点协同作用下储罐的多米诺失效概率增大,罐区危险性增强,可以通过对储罐设置安全屏障等措施,有效的切
断导致事故最大概率的链条。 相似文献