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91.
通过建立南京市机动车排气污染网络监管系统,将车辆上牌、尾气年检、路检抽检、公交治理、标志管理、区域限行、维修治理等有关机动车污染控制的工作环节纳入到系统中,实现全过程在线实时监控,以保证工作过程的规范性、检测数据的真实性和监督管理的科学高效性。 相似文献
92.
显色环保型融雪剂的研制 总被引:1,自引:0,他引:1
研究开发显色环保型融雪剂,添加了缓蚀剂和对植物生长有益的植物钙剂,能够减少对金属、路面、植物等的腐蚀,并根据融雪剂颜色的变化,控制融雪剂用量。试验结果表明:显色环保型融雪剂使用量在20 g以下时,融冰量随着融冰时间的增加而增加,融冰量在融冰时间80分钟左右达到最大值,80分钟以后融冰量随着融冰时间的增加而减少,最佳融冰比为1:5(1份融雪剂:5份冰)。三种融雪剂的融冰效果为:自制融雪剂〉市售融雪剂〉氯化钠,且自制融雪剂对金属的腐蚀性小,对植物的生长基本没有影响。 相似文献
93.
含铬电镀废水的资源化处理 总被引:5,自引:1,他引:4
针对电镀厂产生的高浓度含铬废水,研究了硫化钠还原沉淀法回收电镀废水中的铬的可能性。讨论了pH、投药量、反应时间和搅拌速率等变量对铬回收效果的影响。结果表明:在pH1.6,工业硫化钠(60%)投加量为4.0g/L废水,搅拌速率170r/min和反应时间t=90min的条件下能够将原水中初始浓度为533.1mg/L的三价铬C(rⅢ)和530.0mg/L的六价铬[C(rⅥ)]分别降到42.9mg/L和0.01mg/L。此时铬渣中三氧化二铬(Cr2O3)含量为29.5%,满足回用要求。接下来,为了进一步去除残余的三价铬C(rⅢ),利用正交试验设计讨论了重金属捕集剂(FZ)对其去除的最佳条件。在上述条件下出水中总铬(TCr)浓度最终降到0.94mg/L。 相似文献
94.
选取滇池福保湾表层沉积物,以聚合氯化铝为钝化剂,研究了扰动强度对钝化剂抑制沉积物中磷释放的影响.结果表明,当扰动强度低于一定范围时,聚合氯化铝对沉积物中的磷有抑制作用,当转速为0,60,120r/min时,对应的水中磷浓度分别为初始值的62.5%,71.7%和83.4%;当转速达到240r/min时,沉积物会向水中释放大量磷,钝化作用完全被破坏,水中磷浓度为初始值的3.3倍.此外,在转速低于120r/min时,磷形态主要是以无机磷(DIP)为主的溶解性磷(DTP),而转速达到240r/min时,水中DTP/TP30%,DIP/DTP40%,即磷形态主要为不溶性磷,溶解性磷中以有机磷(DOP)为主. 相似文献
95.
Likun Gu Zhihui Bai Bo Jin Jianyun Zhang Wenying Li Guoqiang Zhuang Hongxun Zhang 《环境科学学报(英文版)》2010,22(9):1407-1412
A phyllosphere bacterial strain EBL-06 was isolated from wheat leaves. The morphology, cultural characteristics, phospholipid fatty acids, physiological and antagonistic fungus activities of this strain were investigated. A phylogenetic tree was constructed by comparing with the published 16S rDNA sequences of the relevant bacteria. The results showed that the isolate EBL-06 was a strain of Paenibacillus polymyxa; this strain performed a high level of antagonistic fungus activity toward a broad spectrum of phytopathogens, such as Botrytis cinerea, Cladosporium cucumerinum, Fusarium spp. The isolate EBL-06 can grow well using monosodium glutamate wastewater (MGW) and potato wastewater (PW) as culture medium. The maximum yield of 6.5 × 10 9 CFU/mL of the isolate EBL-06 anti-fungus biocontrol agent was reached in 15 hr cultivation at 28°C, pH 6.0–7.5 using the mixture of MGW and PW (1:9). 相似文献
96.
When the dark ones become darker: How promotion focus moderates the effects of the dark triad on supervisor performance ratings 下载免费PDF全文
The current study adds to a growing body of research on dark personality traits by investigating the moderating role of promotion focus on the relationships among dark triad traits and facets of job performance. Specifically, we investigated the effects of the dark triad (i.e., Machiavellianism, narcissism, and psychopathy) on supervisor ratings of performance, and the moderating effect promotion focus has on those effects. Using field data, we surveyed 549 employees from a manufacturing company in the USA and obtained supervisor ratings of task performance and helping behavior for each employee. We found support for multiple hypotheses, which suggests that managers rated narcissistic and psychopathic employees as having poorer task performance and psychopathic employees as engaging in fewer helping behaviors than employees low in those traits. Furthermore, promotion focus strengthened these negative relationships. We did not find these effects for Machiavellianism. Implications of these findings for future dark personality research as well as the practical implications for managers and organizations are discussed. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
97.
98.
以湖南长沙某铬盐厂铬渣为研究对象,通过室内模拟实验,采用振荡淋洗方法研究了硫酸-硫酸钠复合淋洗剂对铬渣污染场地Cr的淋洗效果,探讨了淋洗剂浓度、液固比和淋洗时间等对淋洗效果的影响,以及淋洗前后重金属形态的变化,并通过对比试验研究了硫酸钠、柠檬酸、草酸、Na2-EDTA、硫酸、柠檬酸-柠檬酸三钠以及盐酸-氯化钠作为淋洗剂对总铬和六价铬的淋洗效果。结果表明:硫酸/硫酸钠复合淋洗剂在浓度为0.4 mol/L,液固比为20∶1,反应时间为6 h,常温条件下可以达到最佳淋洗效果,总铬和六价铬的浸出效率分别为70.35%和71.56%;另外,重金属形态分析表明,该复合淋洗剂有效减少了铬渣中弱酸可提取态和有机物结合态Cr的百分比,使得残渣态Cr的百分比增加,从而降低了Cr的活性,达到修复目的。淋洗剂对比试验结果表明,与其他淋洗剂相比,硫酸-硫酸钠淋洗效果最好,其中的氢离子能与Cr~(3+)进行离子交换,而硫酸根能够有效地将钙与六价铬分离,对此高钙铬渣的处理更具针对性和有效性。 相似文献
99.
The present study deals with the development of an efficient and reliable process for safe disposal of coal fly ash to remove arsenic that has been found to be the most easily leachable and hazardous heavy metal in coal fly ash. Pre‐leaching of fly ash prior to disposal by a natural chelating agent, sodium gluconate (SG), was proposed and studied. Several operational factors influencing arsenic leachability, such as concentration of SG solution, liquid to solid ratio, pH, length of leaching time and leaching temperature were examined. Arsenic was found to leach out substantially with SG, but almost no further release was observed from the ash pre‐leached by SG. After the pre‐leaching treatment, the desirable high buffering capacity of the ash was well sustained. SG solution was effectively regenerated by activated alumina adsorption so that it could be successfully reused for multiple leaching/adsorption cycles. 相似文献
100.