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超声波降解水体中有机物的研究及发展 总被引:11,自引:0,他引:11
超声波降解有机物是一种新型水处理技术。本文介绍了声解机理及近几年超声波降解水体中有害有机物的最新成果,并探讨这一新技术的研究方向。 相似文献
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超声辐照降解水中氯苯的研究 总被引:3,自引:0,他引:3
研究了超声辐照工艺技术降解水中氯苯的效果和影响因素,包括声强、溶液pH值、初始浓度、溶解气体和自由基清除剂,并探讨了氯苯超声降解的机理。试验结果表明氯苯的超声降解主要在空化泡内热解,降解效果好。 相似文献
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可发性聚苯乙烯泡沫塑料的开发应用陈建忠1可发性聚苯乙烯泡沫塑料的性能及应用范围我处生产的可发性聚苯乙烯泡沫塑料,是以聚苯乙烯树脂为基材掺和戊烷发泡剂,含发泡剂的聚苯乙烯珠粒经预发泡和模型再发泡成型而制成。具有柔软性和弹性,比重很小(0.012g/cm... 相似文献
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以直接桃红模拟废水为研究对象,声强、溶液pH、饱和气体和无机盐为影响因素,对低频超声波作用于直接桃红废水的降解规律和降解机理进行了初步探讨。试验结果表明:在反应体系中加入NaCl和CuSO4,有助于提高直接桃红废水的降解率,而加入K2CO3会抑制直接桃红废水的超声降解效果;通入饱和气体也可促进直接桃红废水的降解率,影响因素大小依次为氩气>空气>氧气>氮气;染料直接桃红废水的初始pH对超声降解效果有重要影响,酸性条件有利于染料的超声降解效果,当pH=3时,可取得最佳的降解效果,而在碱性条件下几乎无降解效果。同时还探讨了超声-H2O2降解直接桃红的协同效应,试验结果表明:H2O2对超声波降解直接桃红废水具有明显的促进作用,且两者存在协同效应。在单独采用超声降解直接桃红废水的试验优化条件下,在反应体系中加入50μL H2O2溶液,超声反应120min,其降解率可达78.03%,具有较好的处理效果。 相似文献
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超声强化臭氧降解高浓度苯酚废水研究 总被引:4,自引:0,他引:4
石新军 《水科学与工程技术》2006,(4):33-36
超声及其组合技术对有机物废水降解是一种新兴的污水处理技术,有着广阔的发展前景和应用市场.对超声强声动力强化臭氧降解高浓度苯酚废水过程中的臭氧通气量、溶液的pH值、反应时间及溶液的初始浓度进行了实验研究,并对单一臭氧和超声强化臭氧降解效果进行了比较.结果表明:由于超声独特的物理、化学效应为臭氧降解提供了极端的物理、化学环境,二者协同作用使得反应进行彻底,COD去除率可达100%. 相似文献
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本文就聚苯乙烯泡沫板在饱和冻胀地基上作为防冻胀体,先后在辽宁省5座支渠闸上的应用情况和效果加以简介。文中还提出关于确定聚苯乙烯板厚的计算方法。 相似文献
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Bin Wang Chang-ping Zhu Run-hang Gong Jin Zhu Bo Huang Fei Xu Qing-gong Ren Qing-bang Han Zhen-bing He 《水科学与水工程》2015,8(3):233-238
The degradation of acephate in aqueous solutions was investigated with the ultrasonic and ozonation methods, as well as a combination of both. An experimental facility was designed and operation parameters such as the ultrasonic power, temperature, and gas flow rate were strictly controlled at constant levels. The frequency of the ultrasonic wave was 160 k Hz. The ultraviolet-visible(UV-Vis) spectroscopic and Raman spectroscopic techniques were used in the experiment. The UV-Vis spectroscopic results show that ultrasonication and ozonation have a synergistic effect in the combined system. The degradation efficiency of acephate increases from 60.6% to 87.6% after the solution is irradiated by a160 k Hz ultrasonic wave for 60 min in the ozonation process, and it is higher with the combined method than the sum of the separated ultrasonic and ozonation methods. Raman spectra studies show that degradation via the combined ultrasonic/ozonation method is more thorough than photocatalysis. The oxidability of nitrogen atoms is promoted under ultrasonic waves. Changes of the inorganic ions and degradation pathway during the degradation process were investigated in this study. Most final products are innocuous to the environment. 相似文献
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水泥土材料目前在寒区工程建设中被广泛应用,寒区气候温度交替变化,对水泥土各方面性能影响较大,因此,研究冻融循环条件下水泥土的损伤劣化特征对于寒区工程建设和工程设计具有重要的参考价值。将取自新疆某边坡的原状土与普通水泥配制成水泥土,在冻结温度为-20 ℃、融解温度为20 ℃条件下分别进行0,3,9,15次冻融循环试验,不同循环次数后对水泥土试样进行单轴抗压强度试验和质量变化测定。在此基础上,采用扫描电镜分析水泥土的微观结构变化,探讨冻融循环条件下水泥土的损伤劣化机制。结果表明,水泥土的抗压强度和剩余质量随着冻融循环次数的增加而降低,水泥土抗压强度随冻融循环次数的变化规律可用关系式Rc=-0.11n+3.29表达。 相似文献
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地震动力特性对于粉煤灰堆场、填筑体的安全至关重要。根据Seed-Idriss公式计算粉煤灰地基地震应力,通过动三轴试验研究50~200 kPa固结应力和3种不同动应力水平下的特性,得出地震下粉煤灰的动变形、动孔压、破坏形式和动模量弱化等特性。研究结果表明:地震循环应力较大时,破坏形式为双幅动应变达到限值;中等循环应力条件下,固结应力为50 kPa时,破坏形式为累积轴向应变达到限值,固结应力>50 kPa时,破坏形式为双幅动应变达到限值;地震循环应力较小时,粉煤灰不发生变形破坏。相同循环周数下,孔压比随着固结应力的增大而降低;达到变形破坏时,孔压远小于液化值。地震循环应力较大时,在10周循环荷载后,粉煤灰动模量迅速弱化;中等循环应力条件下,循环周数大于临界值后模量弱化指数迅速降低;地震循环应力较小时,粉煤灰的模量弱化不明显。研究成果可为粉煤灰堆场、地基、坝体等的动力计算提供依据。 相似文献
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采用超声波传播理论,分析了超声波在液滴表面的传播形式,确定了超声波对液滴的作用方式;对液滴表面做Rayleigh-Taylor (R-T)不稳定性分析,建立液滴表面扰动波的色散方程,分析不同速度和不同粒径的液滴在不同频率的超声波作用下由R-T不稳定性引起的表面扰动波的最大增长率和相应的波长,并探讨在此情况下液滴稳定的临界条件. 相似文献
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The photochemistry of para-chlorophenol (4-CP) was studied under simulated sunlight (lambda > 300 nm) and UV irradiation by using a 125 W high-pressure mercury lamp with or without a hard glass as light source in an ice matrix. The experiments were carried out in a photochemical cold chamber reactor at -14 to -12 degrees C. The photoconversion rate, photoproducts and photoconversion mechanism of 4-CP were all inspected and compared. The results show that the 4-CP photoconversion obeys the first order kinetic model and its photoconversion rate is highly affected by the initial concentration of 4-CP, light intensity and water quality. It is found that the conversion rate of 4-CP under UV irradiation is higher than that under simulated sunlight irradiation. The intermediate products of 4-CP were characterized by GC-MS, HPLC-ESI-MS and HPLC techniques and the possible photoconversion mechanism was proposed accordingly. It is concluded that the mechanism and photoproducts of 4-CP photolysis in ice are different from those in water, and the photoproducts and photoconversion pathways of 4-CP in ice varied with different light sources. 相似文献
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为研究西北干寒地区聚丙烯纤维混凝土建筑物受到干湿-冻融双因素耦合作用下产生的材料耐久性问题,设计室内加速试验,模拟该地区聚丙烯纤维混凝土在干湿和冻融作用下的劣化过程,并以质量损失率和抗压强度损失率为劣化指标进行研究;选用全阶时间幂灰色预测模型对抗压强度损失率变化过程进行建模,确定了对应试验工况下模型的最优结构形式。研究表明:试件的质量损失率经时变化规律为先减小、后增加、再减小直至试验结束,试件的抗压强度损失率经时变化规律为先减小、后增加直至破坏;在试验所取的纤维掺量范围内,0.9 kg/m3的纤维掺量对试件抵抗干湿-冻融破坏能力的改善效果最为明显,试验结束时该掺量下的试件还未达到破坏标准,而其他掺量下的试件均已破坏;当时间幂项阶数h=3时,全阶时间幂灰色预测模型与聚丙烯纤维混凝土劣化过程的原始数据之间的拟合度达到98%,预测值与实际值之间的相对误差低于0.15。室内加速试验和全阶时间幂灰色预测模型的结合,为混凝土结构耐久性设计及寿命预测提供了理论支持。 相似文献
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Reactive Brilliant Red X-3B in aqueous solution could be degraded rapidly by zero-valent iron/activated carbon in the presence of microwave irradiation (ZVI/AC/MW). From the analysis of ultraviolet-visible adsorption, chemical oxygen demand, total organic carbon, infrared spectra and capillary electrophoresis, we found the degradation was complete and no intermediates remained in the final solution treated for 2 min. Considering the many advantages including high degradation ratios, short reaction time, low costs, no intermediates and no secondary pollution, this method might be fit for dealing with various azo dye wastewaters on a large scale. 相似文献