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141.
Methyl ten-butyl ether (MTBE), a gasoline additive, possesses serious problems to the environmental health. In the present study, a bacterial culture named A-3 which could effectively degrade MTBE was isolated from the MTBE contaminated soil. The isolate was identified as Chryseobacterium sp., a new species capable of degrading MTBE. In order to enhance its degradation ability, selected environment factors were investigated. The results showed that the optimal temperature was in the range of 25-30℃, the pH was 7.0, the inoculum size was 2 × 10^8 CFU/ml and the optimal concentration of MTBE was from 50 to 100 mg/L. The maximum MTBE utilization rate (Vmax) was 102 nmol MTBE/(mg cell protein.h). Furthermore, it was found that the isolate could also degrade tert-butyl alcohol (TBA). The degradation rates of TBA were much faster than those of MTBE. The additional TBA would lead to the decrease of the initial MTBE degradation rate and the inhibitory effect of TBA increased with the increase of TBA concentration. Similar protein profiles at least seven peptides were demonstrated after SDS-PAGE analysis of crude extracts obtained from the cells growing in MTBE and TBA culture.  相似文献   
142.
采用好氧与电絮凝联合工艺处理糖蜜酒精厌氧出水,考察COD和色度的去除效果.首先,采用SBR工艺去除废水中的易降解污染物.结果表明:采用SBR法处理稀释10倍的糖蜜酒精厌氧出水,适宜的水力停留时间为10 h;COD去除率为42%,脱色效果不明显,BOD5/COD由0.54下降到0.09,好氧出水难以生化降解.进一步采用电絮凝法处理好氧出水,并考察了极板间距、初始pH值、电流密度和电解时间等因素对COD去除及脱色效果的影响.结果表明,在极板间距为3 cm、废水pH=7.83(无须调节,最佳pH=6~8)、电流密度为10 mA/cm2、电解时间为30 min的条件下进行电絮凝处理,与稀释10倍的糖蜜酒精厌氧出水相比,COD总去除率可达86%,脱色率达95%.  相似文献   
143.
载乙醇活性炭在微波场中的升温行为研究   总被引:3,自引:0,他引:3  
研究了载乙醇活性在微波场中的升温行为,主要包括水和乙醇在微波场中的升温情况,以及微波功率,活性炭量,氮气线速对活性炭升温行为的影响,结果表明,水与乙醇在微波场中能吸收微波能,从而使其温度升高,微波功率越大,活性炭升值越快,活性炭最高温度也更高,活性炭少于5g时温度上升速率随活性炭量的增加而加快,活性炭量多于5g时则相反,氮气线速增加,活性炭升温速率下降,活性炭最高温度降低。  相似文献   
144.
王阳毅  高强  刘赛  葛明桥 《化工环保》2017,37(6):644-647
研究了亚铁盐中NO3-、SO42-、Cl-、Br-等阴离子对Fenton氧化降解高浓度聚乙烯醇(PVA)效果的影响。实验结果表明:酸性条件下具有氧化性的阴离子NO3-或能被氧化形成具有氧化性物质的离子Cl-、Br-对Fenton氧化降解PVA有协同促进作用,且氧化性越强越容易促使PVA大分子链断裂;含NO3-、Cl-、Br-和SO42-的Fenton氧化降解PVA,COD去除率分别为70.05%、70.60%、72.40%和87.90%。采用COD去除率相差不大、产物分子量较小的硝酸亚铁、氯化亚铁、溴化亚铁中的一种作为Fenton试剂催化降解PVA较适宜。  相似文献   
145.
Objective: In Sweden, a joint action method called SMADIT is in use, where the police quickly offer help from the social services or the dependency care and treatment service to suspected drink drivers. The objective of this article is to analyze the experiences of suspected drink drivers who accepted the offer of help and what it meant for them. The knowledge can be used to improve procedures and consultations. Furthermore, it can allow the basic premises of the method to be examined; for example, the importance of offering help quickly.

Methods: To enable comparisons over time, in-depth interviews were conducted with 12 suspected drink drivers on 2 occasions with 1 year between.

Results: To varying degrees the informants knew about their alcohol problems but were unsure whether they would have sought help by themselves. Therefore, the original ideas of the method with an initial contact with the social services or the dependency care and treatment service within 24 h was found to be important. However, the results also showed that some of the informants needed some time before the first meeting because they were in shock from the drink driving incident or in need of sleep. Therefore, the drink driver's situation and individual wishes always have to be considered. The article also shows that an encouraging attitude among the police, the social services, and the dependency care and treatment service is important for the success of the SMADIT method.

The informants are satisfied with the method and in retrospect the incident and the SMADIT offer of help are described as a turning point in their lives. One year after being offered help the informants were no longer focused solely on the personal consequences of drink driving, as they were shortly after the incident. Instead, they had gained insights into the harm they could have done to other road users when they drove while drunk.

Conclusions: One conclusion from this article is that SMADIT, as an innovative method that can be deployed more rapidly than other alcohol-impaired driving countermeasures, should be considered as a good complement to conventional methods to deal with drink driving. Based on the results, we recommend a trial of the joint action method against drink driving in other jurisdictions.  相似文献   

146.
应用酵母菌对木薯酒精废液进行了小型批量的处理试验研究.结果表明,该菌种对于高浓度有机废水具有很强的适应能力,能迅速形成优势菌群,分解有机物.在进水pH 5.0~5.5、温度30℃、曝气时间72 h、接种量1‰(v/v,活菌数为4.1×106个/mL)、溶解氧2~3 mg/L、BOD5∶N∶P为400∶2∶1条件下,COD和BOD5去除率可分别达85%和92%.该技术操作简单,可作为木薯酒精废液的一级生物处理,并可回收利用酵母蛋白.  相似文献   
147.
A novel magnetically recoverable thioporphyrazine catalyst (CoPz(S-Bu)8/SiO2@Fe3O4) was prepared by immobilization of the cobalt octkis(butylthio) porphyrazine complex (CoPz(S-Bu)8) on silica-coated magnetic nanospheres (SiO2@Fe3O4). The composite CoPz(S-Bu)8/SiO2@Fe3O4 appeared to be an active catalyst in the oxidation of benzyl alcohol in aqueous solution using hydrogen peroxide (H2O2) as oxidant under Xe-lamp irradiation, with 36.4% conversion of benzyl alcohol, about 99% selectivity for benzoic acid and turnover number (TON) of 61.7 at ambient temperature. The biomimetic catalyst CoPz(S-Bu)8 was supported on the magnetic carrier SiO2@Fe3O4 so as to suspend it in aqueous solution to react with substrates, utilizing its lipophilicity. Meanwhile the CoPz(S-Bu)8 can use its unique advantages to control the selectivity of photocatalytic oxidation without the substrate being subjected to deep oxidation. The influence of various reaction parameters on the conversion rate of benzyl alcohol and selectivity of benzoic acid was investigated in detail. Moreover, photocatalytic oxidation of substituted benzyl alcohols was obtained with high conversion and excellent selectivity, specifically conversion close to 70%, selectivity close to 100% and TON of 113.6 for para-position electron-donating groups. The selectivity and eco-friendliness of the biomimetic photocatalyst give it great potential for practical applications.  相似文献   
148.
固定化细胞生产L-苯丙氨酸研究   总被引:1,自引:0,他引:1  
用聚乙烯醇(PVA)凝胶包埋固定假单胞菌E4-106细胞,最佳ρ(PVA)为80g/L;最适湿细胞包埋量为每ml凝胶0.3g;转氨酶活力回收率为78%,连续反应21批次后,固定化细胞酶活力为初始最高活力的91%;用固定化细胞进行间歇式批次反应,结果表明其酶活性半寿期为4个月;制得的固定化细胞为直径约3mm的珠状颗粒,机械强度良好,间歇式批次反应10个月,固定化细胞凝胶颗粒无溃破  相似文献   
149.
Objective: Standard deviation of lateral position (SDLP) is often the primary outcome in experimental studies on impaired driving. However, other measures may be easier and more practical to obtain and reflect a broader range of driving-related behaviors. We wanted to assess the validity and sensitivity of a range of measures in a driving simulator as well as during real driving and compare these to SDLP.

Methods: Twenty healthy male volunteers undertook 6 driving trials each, 3 in a regular car on a closed track resembling rural road conditions and 3 in a simulator with an identical driving scenario. Ethanol was used as impairing substance due to its well-characterized effects on driving. The subjects were tested sober and at blood alcohol concentrations (BAC) of approximately 0.5 and 0.9 g/L. We explored dose–response relationships between BAC and a range of driving-related measures, as well as their BAC-dependent effect sizes.

Results: In simulator driving, ethanol intake increased steering wheel reversal frequency, steering wheel movement measures, average speed, standard deviation of speed, and pedal use frequency. At the test track, only steering wheel movement and standard deviation of speed were significantly correlated to BAC. Likewise, reaction to unexpected incidents and observance of red traffic lights were adversely affected by ethanol in the simulator but not at the test track. Whereas SDLP showed a relatively large effect size that was similar in simulated and real driving, all other measures demonstrated smaller effect sizes, with less pronounced BAC effects on the test track than in the simulator.

Conclusions: The results suggest that the driving-related measures explored in this study are less sensitive to alcohol-mediated driving impairment than SDLP, especially during real (test track) driving. The discrepancy in effect sizes between simulated and real driving may imply low external validity of these measures in simulator studies.  相似文献   

150.
本文报道了含氮有机膦及其叔胺氧化物在冷却水系统中的缓蚀与阻垢性能,结果表明,叔胺氧化物与Na_2MoO_4复配时呈现出良好的协同效应.  相似文献   
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