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241.
Objective: The objective of this study was to describe self-reported high alcohol use at each of the 3 licensing stages of graduated driver licensing and its relationship to drink-driving behaviors, intentional risky driving, aggressive driving, alcohol traffic offenses, non-alcohol traffic offenses, and traffic crashes.

Methods: The New Zealand Drivers Study (NZDS) is a multistage, prospective cohort study of newly licensed drivers interviewed at all 3 stages of the graduated driver licensing system: learner (baseline), restricted (intermediate), and full license. At each stage, alcohol use was self-reported using the Alcohol Use Disorders Identification Test (AUDIT-C), with high alcohol use defined as a score of ≥4 for males and ≥3 for females. Sociodemographic and personality data were obtained at the baseline interview. Alcohol-related, intentional risky, and aggressive driving behaviors were self-reported following each license stage. Traffic crashes and offenses were identified from police records. Crashes were also self-reported.

Results: Twenty-six percent (n = 397) reported no high alcohol use, 22% at one license stage, 30% at 2 stages, and 22% at 3 stages. Poisson regression results (unadjusted and adjusted) showed that the number of stages where high alcohol use was reported was significantly associated with each of the outcomes. For most outcomes, and especially the alcohol-involved outcomes, the relative risk increased with the number of stages of high alcohol use.

Conclusions: We found that high alcohol use was common among young newly licensed drivers and those who repeatedly reported high alcohol use were at a significantly higher risk of unsafe driving behaviors. Recently introduced zero blood alcohol concentration (BAC) should help to address this problem, but other strategies are required to target persistent offenders.  相似文献   

242.
Objective: It is well known that alcohol and drugs influence driving behavior by affecting the central nervous system, awareness, vision, and perception/reaction times, but the resulting effect on driver injuries in car crashes is not fully understood. The purpose of this study was to identify factors affecting the injury severities of unimpaired, alcohol-impaired, and drug-impaired drivers.

Method: The current article applies a random parameters logit model to study the differences in injury severities among unimpaired, alcohol-impaired, and drug-impaired drivers. Using data from single-vehicle crashes in Cook County, Illinois, over a 9-year period from January 1, 2004, to December 31, 2012, separate models for unimpaired, alcohol-impaired, and drug-impaired drivers were estimated. A wide range of variables potentially affecting driver injury severity was considered, including roadway and environmental conditions, driver attributes, time and location of the crash, and crash-specific factors.

Results: The estimation results show significant differences in the determinants of driver injury severities across groups of unimpaired, alcohol-impaired, and drug-impaired drivers. The findings also show that unimpaired drivers are understandably more responsive to variations in lighting, adverse weather, and road conditions, but these drivers also tend to have much more heterogeneity in their behavioral responses to these conditions, relative to impaired drivers. In addition, age and gender were found to be important determinants of injury severity, but the effects varied significantly across all drivers, particularly among alcohol-impaired drivers.

Conclusions: The model estimation results show that statistically significant differences exist in driver injury severities among the unimpaired, alcohol-impaired, and drug-impaired driver groups considered. Specifically, we find that unimpaired drivers tend to have more heterogeneity in their injury outcomes in the presence potentially adverse weather and road surface conditions. This makes sense because one would expect unimpaired drivers to apply their full knowledge/judgment range to deal with these conditions, and the variability of this range across the driver population (with different driving experiences, etc.) should be great. In contrast, we find, for the most part, that alcohol-impaired and drug-impaired drivers have far less heterogeneity in the factors that affect injury severity, suggesting an equalizing effect resulting from the decision-impairing substance.  相似文献   

243.
在中温条件下,对pH值和营养比例2个影响因素进行了糖蜜酒精废液的BMP分析,探讨酒精废液在厌氧消化过程中产甲烷量、COD浓度的变化情况,以及COD去除率与产气量、pH值之间的关系.研究结果表明,厌氧处理法能够使糖蜜酒精废液的有机负荷大大降低,COD去除率最高可达90.6%.在调节营养比例的条件下,pH=8.5时甲烷菌活性最佳,其中COD:P=300:1的产甲烷量最高.  相似文献   
244.
介绍抚顺醇醚化学厂醇醚生产废水的排放与水质特点 ,结合工艺流程介绍处理工艺设计和技术参数。几年来的运行结果表明 ,采用生物滤池 生物接触氧化 纤维球过滤三级工艺处理醇醚表面活性剂废水 ,处理效果良好 ,出水CODCr<10 0mg/L ,SS <15mg/L ,滤后水可用于厂区绿化。  相似文献   
245.
Biotic and abiotic transformations of methyl tertiary butyl ether (MTBE)   总被引:1,自引:0,他引:1  
Background Methyl tertiary butyl ether (MTBE) is a fuel additive which is used all over the world. In recent years it has often been found in groundwater, mainly in the USA, but also in Europe. Although MTBE seems to be a minor toxic, it affects the taste and odour of water at concentrations of < 30 μg/L. Although MTBE is often a recalcitrant compound, it is known that many ethers can be degraded by abiotic means. The aim of this study was to examine biotic and abiotic transformations of MTBE with respect to the particular conditions of a contaminated site (former refinery) in Leuna, Germany. Methods Groundwater samples from wells of a contaminated site were used for aerobic and anaerobic degradation experiments. The abiotic degradation experiment (hydrolysis) was conducted employing an ion-exchange resin and MTBE solutions in distilled water. MTBE, tertiary butyl formate (TBF) and tertiary butyl alcohol (TBA) were measured by a gas chromatograph with flame ionisation detector (FID). Aldehydes and organic acids were respectively analysed by a gas chromatograph with electron capture detector (ECD) and high-performance ion chromatography (HPIC). Results and Discussion Under aerobic conditions, MTBE was degraded in laboratory experiments. Only 4 of a total of 30 anaerobic experiments exhibited degradation, and the process was very slow. In no cases were metabolites detected, but a few degradation products (TBF, TBA and formic acid) were found on the site, possibly due to the lower temperatures in groundwater. The abiotic degradation of MTBE with an ion-exchange resin as a catalyst at pH 3.5 was much faster than hydrolysis in diluted hydrochloric acid (pH 1.0). Conclusion Although the aerobic degradation of MTBE in the environment seems to be possible, the specific conditions responsible are widely unknown. Successful aerobic degradation only seems to take place if there is a lack of other utilisable compounds. However, MTBE is often accompanied by other fuel compounds on contaminated sites and anaerobic conditions prevail. MTBE is often recalcitrant under anaerobic conditions, at least in the presence of other carbon sources. The abiotic hydrolysis of MTBE seems to be of secondary importance (on site), but it might be possible to enhance it with catalysts. Recommendation and Outlook MTBE only seems to be recalcitrant under particular conditions. In some cases, the degradation of MTBE on contaminated sites could be supported by oxygen. Enhanced hydrolysis could also be an alternative. - * The basis of this peer-reviewed paper is a presentation at the 9th FECS Conference on 'Chemistry and Environment', 29 August to 1 September 2004, Bordeaux, France.  相似文献   
246.
减少显色剂中HgCl2,KI的含量,以聚乙烯醇做胶体稳定剂,显著提高了显色剂的稳定度和显色的稳定度,以KOH和酒石酸做缓冲液,保持恒定的显色碱度,同时也隐蔽了金属离子的干扰,从而大大降低了空白吸光度和检测限。废水予处理,通过条件实验,确定了稀释比,稀释水样用絮凝沉淀法或蒸馏法处理,蒸馏时用磷酸盐缓冲液,并降低硼酸吸收液的浓度,提高了回收率。  相似文献   
247.
树脂吸附法处理硝化废水   总被引:1,自引:0,他引:1  
杨旭  俞飞 《污染防治技术》2007,20(3):9-12,78
从14种树脂中筛选出国产大孔吸附树脂AB-8用来处理硝化废水,对硝基苯、硝基氯苯和CODcr,的去除率分别可达70%、99%和43%;用工业乙醇作脱附剂,洗脱效果较好,树脂再生后可重复使用。  相似文献   
248.
 Polychlorinated biphenyls (PCBs), a type of persistent organic pollutants (POPs), are considered to be endocrine disrupters. According to the Stockholm Convention on POPs, PCB detoxification is being accelerated globally. We have developed an environmentally sound chemical PCB detoxification plant using the ultraviolet ray/catalyst method. The purpose of this paper is to check the design methodology for the PCB detoxification plant by the application of probabilistic safety analysis. First, possible hazardous events were determined; second, the weakest points in these hazardous events were established; and third, the impact when failures arise at the weak points in the system were studied. We clarified the preventive measures as follows. To prevent PCBs leaking into the environment, select leak-tight valves for the piping containing PCBs, and reduce the number of valves. To prevent fire or explosions due to leaks of an inflammable mixture, select leak-tight valves, reduce the number of valves installed in the piping, and improve the reliability of the suppression tank in the isopropyl alcohol (IPA) recovery unit. Received: February 27, 2001 / Accepted: June 17, 2002  相似文献   
249.
CDPVA是一种具有共轭多烯序列的聚乙烯醇(PVA)衍生物。通过低温热处理法制备了CDPVA/ZnO复合光催化剂。表征结果显示,PVA经低温热处理后形成了具有一定共轭结构的CDPVA并包覆于纳米ZnO颗粒表面,提高了光催化剂的可见光响应能力,有效促进了光生空穴和电子的分离。当PVA与纳米ZnO的质量比为1∶100时,CDPVA/ZnO的可见光催化活性最高;在催化剂投加量为0.5 g/L、初始罗丹明B质量浓度为4 mg/L、可见光照射50 min的条件下,罗丹明B降解率为97.51%,明显优于纯纳米ZnO;CDPVA/ZnO循环使用9次后仍保持较高的罗丹明B降解率,表明CDPVA的包覆有效抑制了纳米ZnO的光腐蚀,提高了光催化剂的稳定性。  相似文献   
250.
射流自吸式生物曝气塔处理废水的研究   总被引:2,自引:0,他引:2  
栾金义  范燕英 《化工环保》1998,18(5):259-262
用射流自吸式生物曝气塔对酒精生产废水及催化剂生产废水的处理进行了试验研究。与普通活性污泥法曝气池相比,射流自吸式生产曝气塔具有处理负荷高,停留时间短,处理量大的特点,是一种新型的生物反应器。  相似文献   
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