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811.
赖氨酸生产废水处理技术研究   总被引:2,自引:0,他引:2  
对赖氨酸生产废水处理进行了试验研究 ,探讨了各种处理方法的优劣 ,并提出了废水清洁处理技术。  相似文献   
812.
Objective: The objective of this study was to understand the social context and circumstances surrounding alcohol-impaired driving prior to fatal crash involvement for drivers with an illegal blood alcohol concentration (BAC ≥ 0.05 g/100 ml or 0.00 g/100 ml for restricted license holders).

Methods: Coroners' case reports investigating fatal crashes in South Australia over a 3-year period (2008–2010) were examined. The personal and crash characteristics of drivers with an illegal BAC were compared with those who had a legal BAC. For each driver with an illegal BAC, information was recorded including characteristics of last trip, location and social context of alcohol consumption, quantity and type of alcohol consumed, BAC level, presence of drugs, perceived alcohol intoxication, and alcohol dependence. Official traffic offense records were also obtained.

Results: Of the 284 fatal crashes included in the study, 34% (n = 95) involved a driver or rider with an illegal BAC. Prior to the crash, alcohol was most frequently consumed by drivers in rural areas, within private homes, and was part of normal social activities. Drivers recorded a high level of alcohol impairment, with a mean BAC of 0.173 g/100 ml and a level of alcohol dependence that was above the Australian national average (7.4 vs. 3.9%). In addition, 23% of drivers were known to be experiencing psychological stress at the time of the crash. The results also confirm that drink driving recidivism continues to be a significant problem, with 44% of drivers recording at least one prior alcohol driving offense.

Conclusions: Alcohol-impaired driving continues to be a leading cause of fatal crashes. The popularity of drinking at home, particularly in rural areas, has implications for police enforcement strategies and suggests that drink driving interventions that focus on community values and looking after friends might be beneficial. Importantly, the study highlights the need for a broader holistic approach to reduce the high levels of alcohol consumption and alcohol dependence underlying drink driving behavior.  相似文献   

813.
Objective: The aim of this study was primarily to evaluate inebriated fatally injured drivers (FIDs) according to blood alcohol concentration (BAC) in a 10-year period (2004–2013) in Autonomous Province (AP) of Vojvodina, Republic of Serbia, to analyze the efficacy of alcohol polices in the new law on road traffic safety through changes in the number of inebriated FIDs before and after implementation of the law, as well as to identify factors that influence the occurrence of FIDs with BACs above the legal limit.

Methods: All data for this retrospective study were obtained from the Centre of Forensic Medicine, Toxicology and Molecular Genetics of Clinical Centre of Vojvodina, Novi Sad. Autopsy records for each case included age, gender, BAC, type of vehicle, and date of accident (year, month, and recalculated day of the week). BAC was determined by gas chromatography with flame ionization detection. Statistical analysis was carried out by chi-square tests and Student's t test, with P < .05 as a statistical significance, and multiple binary logistic regression.

Results: Of the 354 inebriated FIDs (60% of all FIDs), the majority had BACs between of 0.031 and 0.3 mg/ml (28%), followed by those with BAC > 2.01 mg/ml (23%). The average BAC of those driving under the influence of alcohol (DUIA) for the whole period was 1.235 ± 1.00 mg/ml and the average number of DUIA/year was 35. Among the total number of FIDs there were significantly more males (93.7%; P < .001) than females (6.3%), though the distribution of intoxicated men and women was not different (P > .05). There was a statistically significant difference in the distribution of sober and inebriated FIDs according to age (P < .001) with the predominance of inebriated FIDs between 21 and 30 years. Although gender and age were found to be significant predictors of BAC above legal limit in FIDs, the area under the receiver operating characteristics (ROC) curve showed that the model had poor discrimination (ROC = 0.673). Of all observed FIDs, 65 cases per year were attributed to the first 5-year period (2004–2009) and 49 to the second 5-year (2010–2013) period, which indicates that there was no statistically significant decrease in the number of FIDs after implementation of the new law.

Conclusion: The highest number of intoxicated FIDs during the period in AP Vojvodina were mildly and completely inebriated. In the 4-year post-policy period (2010–2013), the number of FIDs and average BAC levels of inebriated FIDs did not significantly change. The abolition of a permissible BAC should be considered.  相似文献   

814.
洛阳化纤PTA装置污水排放的综合治理   总被引:1,自引:0,他引:1  
根据洛阳化纤工程PTA装置污水排放情况及与之配套的化纤污水处理场的处理情况,采取一系列有效措施,治理源头,达到PTA高浓度有机污水达标排放的目的。  相似文献   
815.
基于最小二乘法的高抽巷CO浓度变化规律分析   总被引:1,自引:0,他引:1  
我国许多煤矿的煤层同时具有高瓦斯和严重自燃倾向,在抽放瓦斯的同时,容易造成采空区遗煤自燃。因此,监测采空区指标气体的浓度变化对预防采空区自燃非常重要。本文采用最小二乘法对山西阳煤五矿8403工作面高抽巷CO浓度进行分析,拟合得出了高抽巷CO浓度变化曲线,并对拟合方法、拟合效果进行了分析。结果表明,用最小二乘法进行拟合是可行、有效的。结合现场实际条件,分析了高抽巷CO浓度偏高的原因和之所以选取分析高抽巷CO浓度来预测采空区自燃的原因。结果显示,分析高抽巷CO浓度变化可以较早地发现采空区自燃。最后,分析了CO浓度与CO2、O2浓度的相关性,验证了用CO浓度预测采空区自燃的准确性。  相似文献   
816.
We report and analyze data on the PM10 fraction of airborne particles measured at five recording stations in the Brussels region from October 2002 till September 2003. These stations are representative of the various activity sectors of the Brussels urban area. The objective was the determination of the origin of the PM10 particles (particles up to 10 μm) that are recorded in that region in order to follow the EU directives concerning tolerance level of airborne particles concentration. In order to evaluate the impacts of local and external factors that inject solid particles in the atmosphere of Brussels we compared concentration data from working and not working (holidays) periods. Moreover, we also compared concentrations from periods of agricultural activity and rest in the Brabant provinces surrounding the Brussels region for various crop types. The results lead to the conclusion that the impact or urban traffic is rather limited while that of the agricultural activities is important. Moreover, there appears a clear-cut distinction between different types of crops.  相似文献   
817.
This study monitored atmospheric pollutants during high wind speed (> 7 m s−1) at two sampling sites: Taichung Harbor (TH) and Wuci traffic (WT) during March 2004 to January 2005 in central Taiwan. The correlation coefficient (R 2) between TSP, PM2.5, PM2.5−10 particle concentration vs. wind speed at the TH and WT sampling site during high wind speed (< 7 m s−1) were also displayed in this study. In addition, the correlation coefficients between TSP, PM2.5 and PM2.5−10 of ionic species vs. high wind speed were also observed. The results indicated that the correlation coefficient order was TSP > PM2.5−10 > PM2.5 for particle at both sampling sites near Taiwan strait. In addition, the concentration of Cl, NO3 , SO4 2−, NH4 +, Mg2+, Ca2+ and Na+ were also analyzed in this study.  相似文献   
818.
Atmospheric aerosol particles and metallic concentrations, ionic species were monitored at the Experimental harbor of Taichung sampling site in this study. This work attempted to characterize metallic elements and ionic species associated with meteorological conditions variation on atmospheric particulate matter in TSP, PM2.5, PM2.5–10. The concentration distribution trend between TSP, PM2.5, PM2.5–10 particle concentration at the TH (Taichung harbor) sampling site were also displayed in this study. Besides, the meteorological conditions variation of metallic elements (Fe, Mg, Cr, Cu, Zn, Mn and Pb) and ions species (Cl, NO3 , SO4 2−, NH4 +, Mg2+, Ca2+ and Na+) concentrations attached with those particulate were also analyzed in this study. On non-parametric (Spearman) correlation analysis, the results indicated that the meteorological conditions have high correlation at largest particulate concentrations for TSP at TH sampling site in this study. In addition, the temperature and relative humidity of meteorological conditions that played a key role to affect particulate matter (PM) and have higher correlations then other meteorological conditions such as wind speed and atmospheric pressure. The parameter temperature and relative humidity also have high correlations with atmospheric pollutants compared with those of the other meteorological variables (wind speed, atmospheric pressure and prevalent wind direction). In addition, relative statistical equations between pollutants and meteorological variables were also characterized in this study.  相似文献   
819.
建立了测定大气颗粒物PM10中18种无机元素的密闭微波消解电感耦合等离子体发射光谱法。考察了微波消解体系和消解条件,选取了适宜的仪器工作条件和最佳的分析谱线,合理地进行了背景扣除,并对共存元素的干扰情况进行了研究。样品采用硝酸-盐酸-过氧化氢-氢氟酸体系进行消解并经饱和硼酸溶液络合后上机测定,测定值与参考样品标准值相符,主量元素的方法精密度(RSD%)小于3%,次量、微量元素的方法精密度小于10%。各元素的检出限在0.0001~0.0141mg/L之间,回收率在90%~110%之间,应用建立的方法对北京市的颗粒物膜样品进行了分析。  相似文献   
820.
新疆城市环境空气PM_(10)自动监测仪器质控巡检工作探析   总被引:1,自引:0,他引:1  
随着城市环境空气质量自动监测业务现代化的飞速发展,新疆城市共安装38套PM10环境空气自动监测系统。本文通过对新疆19个城市空气自动监测系统PM10的巡检和质控考核,发现近几年来该系统运行维护中的诸多问题,从而提出仪器维护注意事项,以期提高新疆城市PM10监测数据质量,准确反映环境空气质量状况,为环境管理和政府决策提供更加科学、准确、可靠的基础监测数据。  相似文献   
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