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81.
基于玉米酒精生产工艺流程,采用实测和物料衡算结合的方法,分析玉米酒精生产关联物料,并建立关联物质量平衡方程。实验测得绝干全玉米的COD负荷值为1611 mg/g,在此基础上推导出玉米酒精生产工艺的COD产污系数与淀粉出酒率、玉米淀粉含量、胚芽收率、玉米油收率、杂醇油收率和干玉米酒糟收率的量化模型。采用国内行业相关参数值代入模型进行核算,并与《第一次全国污染源普查工业污染源产排污系数手册》和《清洁生产标准酒精制造业》(HJ 581—2010)中的相关系数进行对比。结果表明:手册值在模型计算范围内;模型计算值略大于标准指标,与标准中一级COD产污指标基本一致。 相似文献
82.
Akio Kamimura Eisuke Konno Shigehiro Yamamoto Takeru Watanabe Kazuo Yamada Fumiaki Tomonaga 《Journal of Material Cycles and Waste Management》2009,11(2):133-137
The synthesis of recycled plastics from recovered monomeric materials obtained from the depolymerization reaction of fiber-reinforced
plastics (FRP) was examined. The depolymerization reaction of FRP in the presence of N,N-dimethylaminopyridine (DMAP) smoothly yielded the corresponding monomers, which mainly consisted of dimethyl phthalates.
The polymerization reaction with this monomer failed to form the corresponding unsaturated polyesters due to contamination
by N-methyl-4-pyridone, a decomposition product of DMAP. An efficient purification of the recovered monomer was achieved by washing
with water, and the purified monomer successfully yielded the corresponding polymers. A hardness test revealed that the polymers
were as hard as the polyester made from virgin materials. The present modification provides a practical method for the preparation
of recycled plastics from depolymerized plastics. 相似文献
83.
Richard D. Blomberg Author Vitae Raymond C. Peck Author Vitae Author Vitae Marcelline Burns Author Vitae Author Vitae 《Journal of Safety Research》2009,40(4):285-292
Problem
The role of alcohol as a major factor in traffic crash causation has been firmly established. However, controversy remains as to the precise shape of the relative risk function and the BAC at which crash risk begins to increase.Methods
This study used a case-control design in two locations: Long Beach, California, and Fort Lauderdale, Florida. Data were collected on 2,871 crashes of all severities and a matched control group of drivers selected from the same time, location, and direction of travel as the crash drivers. Of the 14,985 sample drivers, 81.3% of the crash drivers and 97.9% of the controls provided a valid BAC specimen.Results
When adjusted for covariates and nonparticipation bias, increases in relative risk were observed at BACs of .04-.05, and the elevations in risk became very pronounced when BACs exceeded .10.Discussion
The results provide strong support for .08 per se laws and for state policies that increase sanctions for BACs in excess of .15.Impact on Industry
This study provides further precision on the deleterious effects of alcohol on driving and, by implication, on other complex tasks. 相似文献84.
Melissa L. McCarthy Author Vitae Peilin Sheng Author Vitae 《Journal of Safety Research》2009,40(3):227-232
Objective
To examine the validity of police-reported alcohol data for drivers involved in fatal motor carrier crashes.Material and Methods
We determined the availability of blood alcohol concentration (BAC) and police-reported alcohol data on 157,702 drivers involved in fatal motor carrier crashes between 1982 - 2005 using Fatality Analysis and Reporting System (FARS) data. Drivers were categorized as motor carrier drivers if they operated a vehicle with a gross vehicle weight rating of greater than 26,000 pounds. Otherwise, they were classified as non motor carrier drivers. The sensitivity and specificity of police-reported alcohol involvement were estimated for both driver types.Results
Of the 157,702 drivers, 18% had no alcohol information, 15% had BAC results, 42% had police-reported alcohol data, and 25% had both. Alcohol information varied significantly by driver, crash, and vehicle characteristics. For example, motor carrier drivers were significantly more likely (51%) to have BAC testing results compared to non motor carrier drivers (31%) (p < 0.001). The sensitivity of police-reported alcohol involvement for a BAC level ≥ 0.08 was 83% (95% CI 79%, 86%) for motor carrier drivers and 90% (95% CI 89%, 90%) for non motor carrier drivers. The specificity rates were 96% (95% CI 95%, 96%) and 91% (95% CI 90%, 91%), respectively.Conclusions
The sensitivity and specificity of police-reported alcohol involvement are reasonably high for drivers involved in fatal motor carrier crashes. Further research is needed to determine the extent to which the accuracy of police-reported alcohol involvement may be overestimated because of verification bias.Impact on the Industry
Based on the results of this study, the federal government should continue to work with states to strengthen their strategies to increase chemical testing of all drivers involved in fatal crashes. 相似文献85.
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89.
Effect of the water–oil ratio on brine/surfactant/alcohol/oil systems optimized for soil remediation
The optimum middle-phase microemulsion used for remediation of oily contaminated soils is often obtained by mixing a certain
amount of a surfactant/alcohol mixture with oil and adjusting the salinity concentrations at a constant water–oil ratio. Upon
introduction to the subsurface, however, the system may not be in the optimum state throughout the remediation process owing
to the change in the water–oil ratio. This research has attempted to investigate the effect of the water–oil ratio on the
phase behavior of systems containing brine, anionic surfactant, alcohols, and different oils. By systematically changing the
water–oil ratio, while keeping the others variables constant, the systems exhibited different phase behavior. The results
revealed that the effect of the water–oil ratio on system behavior was significant, and analogous to that of salinity. Increasing
the water–oil ratio led the system change from winsor I → winsor III → winsor II. The greater the water–oil ratio the lower
the salinity required to produce the middle-phase microemulsion, but the narrower the salinity range of the three-phase region.
An empirical correlation has been developed in order to predict the changes in phase behavior with the changes in water–oil
ratio. This provides a useful tool for designing optimum formulations suitable for soil remediation.
Received: October 5, 1999 / Accepted: March 27, 2000 相似文献
90.
An experimental research into the aqueous photocatalytic oxidation (PCO) of organic groundwater pollutants, methyl-tert-butyl ether (MTBE), tert-butyl alcohol, phenol, humic substances, 2-ethoxy ethanol and ethylene glycol was undertaken using visible light-sensitive
nitrogen-doped titanium dioxide photocatalysts. Nitrogen-doped titania proved to be an effective photocatalyst for MTBE with
its action comparable to and even surpassing that of Degussa P25. In contrast, with the other substances the photocatalysts
showed negligible activity. This difference was explained by the poor adsorption properties of N-doped catalysts. The predominance
of different PCO mechanisms dependent of the surface properties of N-TiO2 catalysts was elucidated. 相似文献