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341.
根据煤气洗涤水的性质,用ClO2 氧化除酚,SL和PAM混凝沉降除悬浮物的方法处理煤气洗涤水。实验结果表明,经处理后废水中的主要污染物酚、焦油和悬浮物等去除率都很高,该水完全可以满足回用要求。  相似文献   
342.
This study developed a moderated mediation model to investigate how family‐supportive paid leave and supervision affect employees' satisfaction with work–family balance and in turn their affective organizational commitment and supervisor‐directed organizational citizenship behavior depending on their perceived insider status in the organization. Our analysis of data collected from 118 employee–supervisor dyads in Korean organizations revealed that satisfaction with work–family balance mediated the linkages from family‐supportive supervision to affective organizational commitment and supervisor‐directed organizational citizenship behavior, and the linkage from family‐supportive paid leave to affective organizational commitment. Results further showed that the entire mediational process for family‐supportive supervision was more pronounced for those who perceived themselves to be an insider of their organizations, while the same pattern was not found for the meditational process related to family‐supportive paid leave. Our findings provide theoretical implications for work–family balance research and offer practical suggestions to make employees satisfied with work–family balance.  相似文献   
343.
Abstract

Objective: Recent news reports in 2016 indicated that across Miami–Dade County, Florida, driving under the influence (DUI) arrests have decreased substantially. The objective of this research was to determine the reasons for the decline in DUI arrests from 2009 to 2016. Are there fewer impaired drivers on the roads? Can DUI enforcement and prosecution be improved?

Methods: The following methods were used in this study: (1) Analysis of existing DUI arrest and crash data; (2) conducting and analysis of a telephone survey of reported knowledge, attitudes, and behaviors concerning impaired driving; (3) conducting and analysis of roadside surveys on the roads on weekend nights in Miami–Dade County; (4) information from focus group discussions with police and prosecutors in Miami–Dade County; and (5) a comprehensive review of the best DUI prevention practices and enforcement strategies used across the country.

Results: DUI arrests decreased 64% in Miami–Dade County between 2009 and 2016. This was a significantly larger decrease than has occurred in the State of Florida as a whole (34%) and in the United States (29%) over the same time period. The decline was not due to any decline in DUI behavior in the county.

Conclusions: Based upon the data and information gathered in this project, the following actions were recommended for Miami–Dade County: (1) County police chiefs need to find ways to overcome law enforcement apathy toward DUI enforcement and persuade their traffic enforcement officers to be proactive rather than reactive when it comes to identifying and making impaired driving stops. (2) County police agencies should join forces to conduct more sobriety checkpoints. Checkpoints are safer for both the police and the drivers going through them and serve as a general deterrent to impaired driving. (3) An interagency DUI task force or team of 5 to 7 officers should be established within the county. These officers would be solely dedicated to DUI enforcement and paid for by each individual agency or under a grant from the state or federal government.  相似文献   
344.
ABSTRACT

Aiming at backfill with crack under the thermo-mechanical (TM) coupling, the concepts of crack macro-damage, loading meso-damage, thermal meso-damage, and total damage of backfill were proposed. Based on the statistical damage theory, considering the coupling effects of temperature, load and initial crack, a damage evolution model of backfill with crack under TM coupling effects was established. Based on this, the strength criterion of backfill with crack considering the effects of thermal and mechanical coupling was constructed by multivariate function full differential method. The research shows that: (1) The theoretical curves of damage evolution model and strength criterion of backfill with crack under TM coupling are in good agreement with the test curves, which verifies the rationality of the model. (2) The initial thermal damage decreases first and then increases with increasing temperature, reaches a minimum value at 40°C, and generally shows a “V” -shaped distribution law. The coupling effect of temperature and crack aggravates the total damage of the backfill. (3) The strength criterion can reflect the relationship between the stress and strain of each limit state and the parameters of backfill with crack under different temperature conditions and can provide a certain reference for the evaluation of the stability of backfill with geological defects such as joints and crack in deep high temperature mines.  相似文献   
345.
采用酸化沉淀-超滤-铁炭微电解-Fenton氧化-混凝沉淀-A/A/O生化处理等联合工艺处理酚类、硝基苯类废水。设计处理水量:物化预处理2 m^3/h、生化处理3 m^3/h。运行结果表明,该工艺处理效果良好,出水pH6~9,COD≤500 mg/L,SS≤400 mg/L,NH3-N≤50 mg/L,TP≤2 mg/L,酚类≤0.5 mg/L,硝基苯类≤2,盐分≤5000 mg/L,出水水质优于设计指标要求。  相似文献   
346.
应用CFD软件Fluent对浸没式膜生物反应器(submerged membrane bioreactor,SMBR)内气液两相流进行数值模拟研究,重点考查曝气系统的改变对气液两相流态的影响,并结合PIV实验验证模拟结果,从而为反应器的优化设计及膜污染的控制提供理论依据。模拟结果表明,SMBR内曝气强化了气液两相紊动,膜表面液相速度沿反应器高度增加且形成循环流动,有利于膜面污染物的脱落;反应器内气含率分布不均匀,出现死区,不利于微生物的生长;经实验验证,模拟结果吻合良好。  相似文献   
347.
选取FeCl3和AlCl2·6H2O作为混凝剂对城市污水进行一级强化混凝处理,降低二级生物处理的进水负荷,减少污水生物处理系统的能量消耗。主要研究混凝过程投加的金属盐对一级强化混凝产生的初沉污泥中温厌氧消化的影响。和剩余污泥相比,初沉污泥更适合厌氧消化处理,污泥降解性能和产气性能更高。当采用城市污水一级强化混凝处理时,污泥中的金属和金属盐水解引起的pH降低,使混凝强化初沉污泥的厌氧消化受到一定抑制。随着污泥中铝含量的降低和铁含量的增加,厌氧消化的COD降解率和挥发性固体(Vs)降解率逐渐升高,生物气产量逐渐增大,产气速率加快。当混凝强化初沉污泥只含有铁时(铁含量为10.16mg/L),混凝强化初沉污泥厌氧消化效果最好,产气稳定,而且产气速率高,生物气产量为237mL,生物气甲烷含量为55.5%,降解单位Vs产气量为0.80L/g,均高于其他含铝的混凝强化初沉污泥。污泥中的铁对初沉污泥厌氧消化的抑制作用远远小于铝的作用,说明铁盐适合用于城市污水的一级强化混凝处理。  相似文献   
348.
金属铁铝对混凝强化初沉污泥中温厌氧消化的影响   总被引:1,自引:0,他引:1  
选取FeCl3和AlCl3·6H2O作为混凝剂对城市污水进行一级强化混凝处理,降低二级生物处理的进水负荷,减少污水生物处理系统的能量消耗。主要研究混凝过程投加的金属盐对一级强化混凝产生的初沉污泥中温厌氧消化的影响。和剩余污泥相比,初沉污泥更适合厌氧消化处理,污泥降解性能和产气性能更高。当采用城市污水一级强化混凝处理时,污泥中的金属和金属盐水解引起的pH降低,使混凝强化初沉污泥的厌氧消化受到一定抑制。随着污泥中铝含量的降低和铁含量的增加,厌氧消化的COD降解率和挥发性固体(VS)降解率逐渐升高,生物气产量逐渐增大,产气速率加快。当混凝强化初沉污泥只含有铁时(铁含量为10.16 mg/L),混凝强化初沉污泥厌氧消化效果最好,产气稳定,而且产气速率高,生物气产量为237 mL,生物气甲烷含量为55.5%,降解单位VS产气量为0.80 L/g,均高于其他含铝的混凝强化初沉污泥。污泥中的铁对初沉污泥厌氧消化的抑制作用远远小于铝的作用,说明铁盐适合用于城市污水的一级强化混凝处理。  相似文献   
349.
在预应力锚索抗滑桩的设计计算中,锚索预应力的取值对抗滑桩的内力计算影响较大,其计算方法仍然是一个需要深入研究的课题,笔者在总结锚索预应力计算方法的基础上,介绍了锚索与桩变形的协调原理,并结合工程实例对其中的3种计算方法进行了对比研究.  相似文献   
350.
搅拌棒萃取-热脱附/气质联用法测定水中2-MIB和土臭素   总被引:3,自引:0,他引:3  
采用搅拌棒萃取-热脱附/气质联用法测定水中2-甲基异莰醇和土臭素,优化了搅拌棒萃取和热脱附进样的条件。试验表明:两种目标化合物在1.00 ng/L~200 ng/L范围内线性良好,2-甲基异莰醇的相关系数为0.9993,土臭素的相关系数为0.9997,方法检出限分别为0.31 ng/L和0.15 ng/L;空白和实际样品的加标回收率为82.4%~116%,测定结果的RSD<10%。  相似文献   
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