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采用Fenton氧化法对青霉素和土霉素混合废水二级处理出水进行深度处理,通过正交和单因素实验研究了废水初始反应pH值、H2O2投加量、Fe2+/H2O2摩尔比及反应时间等因素对废水处理效果的影响。实验结果表明,Fenton氧化法处理的最佳反应条件为:初始pH值4、H2O2(30%)投加量50 mL/L、Fe2+/H2O2摩尔比1/20和反应时间60 min,处理后出水COD小于120 mg/L,COD去除率在75%以上,急性毒性(HgCl2毒性当量)小于0.07 mg/L,满足《发酵类制药工业水污染物排放标准》(GB21903-2008)表2标准要求。 相似文献
214.
基于光合色素的化学分类法在淡水藻类研究中的应用 总被引:2,自引:0,他引:2
采用反相高效液相色谱技术(RP HPLC)系统研究了我国主要淡水藻类--蓝藻、绿藻、硅藻、甲藻、金藻、裸藻和隐藻等的光合色素,在8种纯培养藻类中共确定类胡萝卜素、叶绿素及其衍生物19种。分离到的主要标志性色素按洗脱时间分别为脱植基叶绿素a、19′ 丁酰氧岩藻黄素、叶绿素c、脱镁叶绿素a、多甲藻素、甲基脱植基叶绿素a、岩藻黄素、新黄质、紫黄质、蓝藻叶黄素、硅甲藻黄素、硅藻黄质、叶黄素、玉米黄素、叶绿素b异构体、叶绿素b、叶绿素a异构体、叶绿素a和β 胡萝卜素;其中在纯培养的铜绿微囊藻中首次鉴定到19′ 丁酰氧岩藻黄素;通过官桥基地的实际监测,证实了该技术应用的可行性,为基于HPLC分析技术的浮游植物化学分类法提供了理论依据。 相似文献
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为了研究微波强化Fenton/活性炭工艺处理高浓度制药废水的影响因素,以阜新某集团公司生产制药原料排出的废水为研究对象,利用静态实验,采用混凝-微波强化Fenton/活性炭工艺对高浓度制药废水进行实验。实验用水为100 mL、COD为576~1 440 mg/L的制药废水,当活性炭投加量为2 g,H2O2投加量为3/4Qth,pH值为5,微波辐照功率和时间分别为500 W和7 min时,COD去除率可达到92.6%,出水COD在42.6~106.6 mg/L范围内。实验结果表明,活性炭的投加量、H2O2的投加量、pH值、微波辐照功率和辐照时间对微波强化Fenton/活性炭工艺的处理效果影响都较显著。 相似文献
217.
This study uses an interactionist approach to examine the moderating effect of follower trait positive affectivity (trait PA) on the relation between transformational leadership and both follower creative performance and organizational citizenship behaviors (OCB). On the basis of responses from 212 employees and their direct supervisors from the research and development department of a company in Mainland China, results support the hypothesized moderation effect. Specifically, the positive influence of transformational leadership on creative performance was significantly reduced for followers who were higher on trait PA (ΔR2 = .02, p < .05). The same pattern, in which followers' trait PA appeared to substitute for the influence of transformational leadership, generalized to the outcome of follower OCB as well (ΔR2 = .04, p < .01). We discussed theoretical and practical implications of these findings. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
218.
Yukun Wang Shuifen Zhan Yan Liu Yan Li 《International journal of occupational safety and ergonomics》2013,19(4):584-588
Objectives. The aim of this article is to reduce the risk of occupational hazards and improve safety conditions by enhancing hazard knowledge and identification as well as improving safety behavior for freight port enterprises. Methods. In the article, occupational hazards to health and their prevention measures of freight port enterprises have been summarized through a lot of occupational health evaluation work, experience and understanding. Results. Workers of freight port enterprises confront an equally wide variety of chemical, physical and psychological hazards in production technology, production environment and the course of labor. Such health hazards have been identified, the risks evaluated, the dangers to health notified and effective prevention measures which should be put in place to ensure the health of the port workers summarized. Discussion. There is still a long way to go for the freight port enterprises to prevent and control the occupational hazards. Except for occupational hazards and their prevention measures, other factors that influence the health of port workers should also be paid attention to, such as age, work history, gender, contraindication and even the occurrence and development rules of occupational hazards in current production conditions. 相似文献
219.
Gas leakage from pipeline leads to significant environmental damages and industrial hazards, so small leakage detection for gas pipeline is essential to avoid these serious leakages. However, because of the high frequency component of leakage signal attenuates quickly, traditional detection method which inspects pressure or vibration signal has problem to get effective information from leakage signal. So, a novel detection method based on acoustic wave is proposed. This paper, firstly, researches on the phonation principle of pipeline leakage and the characteristic of sound source, and simulates the leakage acoustic field on the basis of aero acoustics. Secondly, using Wavelet Packet Transform method and Fuzzy Support Vector Machine pattern classification, the laboratory testing for identifying acoustic signal of gas pipeline leakage is presented. Finally, the field application demonstrates that the detection system could identify small gas leakage effectively and avoids false-alarms which caused by running conditions with a good prospect. 相似文献
220.
模拟破片是人体装甲防弹性能测试评价的主要试验弹体.本文对人体装甲和模拟破片进行了阐释,分析了模拟破片的应用背景,对国内外现状进行了对比分析,对标准模拟破片的确定以及爆炸破片的发展进行了探讨,提出了开展新型模拟破片及其测试技术研究的重要意义. 相似文献