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61.
磁种和磁处理技术在废水处理中的应用   总被引:23,自引:0,他引:23  
综述了微细粒磁性颗粒(磁种)在水中对许多污染物具有吸附和絮凝作用,用一些物理和化学方法可使其作用范围扩大。吸附剂与磁咱结合细菌吸附磁性离子等手段可实现加种,磁种作用与磁处理工艺相结合,扩大了磁场处理废水的范围,提高了废水处理的技术经济效益。  相似文献   
62.
焙烧态镁铝水滑石处理阴离子染料废水研究   总被引:8,自引:0,他引:8  
采用传统过饱和双滴法合成出Mg/Al为3的碳酸根型水滑石(LDH),经500℃高温煅烧制备出焙烧产物(CLDH),用x-射线、红外光谱和电镜对它们进行了表征。分别考察了焙烧温度、反应时间、pH、投加量、反应温度和初始浓度等因素对焙烧态水滑石吸附酸性铬蓝K模拟废水效果的影响。结果表明,对于100mg/L的铬蓝K溶液,500℃焙烧态水滑石,投加量为0.06g,在pH=3.5左右,室温下反应1h,去除率最高可达98%以上。四次回收重复利用的CLDH对铬蓝K的去除率仍为90%以上,CLDH是一种良好的环保吸附材料。  相似文献   
63.
The Basque country magnetic anomaly follows a NW-SE trend over the Basque country (northern Spain) with intensities up to 250 nT measured at 3000 m above sea level. The paired negative part of the anomaly is located to the north and presents intensities down to −60 nT. A model of the magnetic properties of the crust in the area, taking into account previous geological and geophysical data, indicates a wedge of material with a magnetic susceptibility of 0.07 SI emplaced along a NE-directed basal thrust. The anomalous wedge is composed of basic and/or ultrabasic Cretaceous intrusives and lower crustal rocks, and reaches a minimum depth which increases towards the northwest from 5–7 to 12 km. According to previous works, geological features of the rocks on top of the anomalous wedge indicate that during the Cretaceous this zone constituted a deep marine environment which underwent important crustal thinning related to rifting. The transition towards the southwest was to a normal continental platform. Alpine deformation gave rise to displacement on a basal thrust, which can be correlated with the lower contact of the magnetic wedge, and emplacement of this wedge towards the northeast. The southeastern termination of the anomaly can be related to the lateral termination of the basic rocks which constitute the anomalous wedge in a transform fault related to the rifting event.  相似文献   
64.
水滑石是一种高效的电吸附材料,可用于工业废水中硫代硫酸盐的去除.硫代硫酸盐(S2O2-3)是废水中主要含硫污染物.本研究采用共沉淀法,在泡沫镍基体上成功合成了Ni Al-LDHs,并经煅烧成功转化为Ni Al-LMO电极.NiAl-LMO电极电化学性能稳定,可逆性好,比电容可达577F·g-1.NiAl-LMO电极在外加电压为1. 0 V、p H为7、温度40℃时,对S2O2-3电吸附效率最高达60.9%,施加相反电压后S2O2-3电脱附率达84.9%.本研究为含S2O2-3废水处理提供了新的电吸附电极材料和技术选择.  相似文献   
65.
Pigeons whose internal clock is shifted by 6 h show deflections from the direction of untreated controls, yet these deflections are often smaller than predicted. Magnets temporarily disabling the magnetic compass increased these the deflections significantly (R. Wiltschko and Wiltschko 2001), indicating a compromise between sun compass and magnetic compass. – Recently, Ioalé et al. (2006) claim that they could not replicate our findings. The reason lies in a difference in the behavior of the clock-shifted pigeons without magnets: in the study of Ioalè et al. (2006), their deflections was already almost as large as that of our pigeons carrying magnets. This difference is probably caused by the limited experience of the pigeons of Ioalè et al. (2006): Their birds, in contrast to ours, had not used their sun’ compass during extended homing flights at various times of the year and, not having been faced with the necessity to compensate the saisonal changes of the sun’s arc, gave the sun compass more weight than our birds did.A comment to the paper by Ioalè, Odetti and Gagliardo (2006) Behav Ecol Sociobiol 60: 516–521.  相似文献   
66.
Pigeons were released at four release sites within the Gernsheim anomaly, a magnetic 'hill' with a peak 199 nT above the regional reference field and gentle 'slopes' to all sides, situated 44 km south of the Frankfurt loft. Local magnetic conditions at the sites differed in total intensity and in direction and steepness of the intensity gradient. At all sites, the pigeons were well oriented, showing counterclockwise deviations from the home directions that were most pronounced in the western part of the anomaly. There was no systematic difference in orientation behavior or homing performance between the sites within the anomaly and a control site outside. No effect of the local gradient direction was found, nor did the difference in intensity between home loft and the release site affect behavior. This argues against the use of magnetic navigational factors. However, pigeons released for the first time within the anomaly tended to have longer mean vectors with increasingly steeper gradients, which could mean that the birds might somehow have realized the anomalous nature of the local magnetic conditions and ignored them, relying on non-magnetic cues instead.Communicated by R. Gibson  相似文献   
67.
磁化除垢器在循环水系统的应用   总被引:5,自引:0,他引:5  
介绍了利用磁化除垢、防垢法研制出的磁化除垢器的基本原理。此产品在工业、民用以及循环水,换热器、暖气、空调等系统上应用,取得了显著的效果。  相似文献   
68.
A magnetic carbon composite, Fe3O4/C composite, was fabricated by one-step hydrothermal synthesis, modified by heat treatment under an inert atmosphere (N2), and then used as an adsorbent for ciprofloxacin (CIP) removal. Conditions for the modification were optimized according to the rate of CIP removal. The adsorbent was characterized by Fourier transform infrared spectroscopy, X-ray diffraction measurements, vibrating-sample magnetometry, scanning electron microscopy, transmission electron microscopy, and N2 adsorption/desorption isotherm measurements. The results indicate that the modified adsorbent has substantial magnetism and has a large specific area, which favor CIP adsorption. The effects of solution pH, adsorbent dose, contact time, initial CIP concentration, ion strength, humic acid and solution temperature on CIP removal were also studied. Our results show that all of the above factors influence CIP removal. The Langmuir adsorption isotherm fits the adsorption process well, with the pseudo second-order model describing the adsorption kinetics accurately. The thermodynamic parameters indicate that adsorption is mainly physical adsorption. Recycling experiments revealed that the behavior of adsorbent is maintained after recycling for five times. Overall, the modified magnetic carbon composite is an efficient adsorbent for wastewater treatment.  相似文献   
69.
为了解决隔爆低频(TBD)型永磁同步电动机(PMSM)中如何利用精确的转子位置和速度信号去实现磁场定向的问题,分析了永磁同步电动机的矢量控制理论,讨论了无传感器矢量控制方案,提出了基于空间电压矢量脉宽调制(SVPWM)技术的矢量控制方案,采用TMS320LF2812为核心处理器进行矢量控制系统的硬件设计,采用DSP编程实现该系统的软件设计,进行了基于无传感器矢量控制系统的仿真研究及实验波形分析。结果表明:无传感器矢量控制方案具有很好的动态特性,能够稳定运行,满足驱动系统的要求。  相似文献   
70.
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