二氧化锰/石墨烯臭氧催化氧化甲苯反应性能

采用一步水热合成法,在180℃,12 h条件下制备了30%二氧化锰/石墨烯(MnO2/G)复合材料。实验结果表明:MnO2均匀且较为牢固地锚定于石墨烯表面,同时MnO2的沉积阻止了多层石墨烯的复合,从而使得复合物具有较大的比表面积。相同条件下,MnO2/石墨烯相较于单纯MnO2或石墨烯具有很好的臭氧催化氧化甲苯性能,这可以归结于MnO2和石墨烯间的协同催化作用。     

臭氧预氧化强化混凝处理引黄水库水的中试研究

针对引黄水库水的特点,采用臭氧预氧化强化常规工艺处理引黄水库水。中试研究结果表明:臭氧预氧化能够降低常规工艺出水浊度,改善对有机物的去除效果,同时提高常规工艺对氨氮和藻类的去除率。适宜的臭氧投加量为1～2mg/L,当臭氧投加量为1mg/L时,臭氧预氧化后,滤后水浊度、CODMn、UV254、氨氮和叶绿素a的去除率,与常规工艺相比分别提高了2.7,2.5,7.8,5.2和4.8个百分点。     

超滤膜与不同处理工艺组合处理湖泊水的中试研究

为解决水厂现有净水工艺不能适应水源水质恶化的现状,采用国产超滤膜分别处理水厂的炭后水(工艺1)、滤后水(工艺2)和沉后水(工艺3),将超滤膜和水厂现有工艺结合,形成深度处理系统,研究超滤膜组合工艺的处理效能及超滤膜的过滤性能。研究表明:工艺1、工艺2和工艺3对CODMn的平均去除率分别为52.86%、39.62%和34.59%;DOC的平均去除率分别为33.08%、23.60%和18.55%,UV254去除率分别为57.14%,39.66%和35.34%,藻类平均去除率分别为98.71%、97.84%和98.13%,3种工艺出水浊度均低于0.1 NTU,颗粒物粒径2μm的颗粒物控制20个/mL以下。工艺1运行45 d跨膜压差上升6.59%,产水率为98.02%;工艺2膜前加氯0.65 mg/L时,水力冲洗后跨膜压差可有效恢复,稳定运行10 d跨膜压差上升2.91%,产水率为97.63%;工艺3运行20 d跨膜压差上升13.52%,其产水率为97.01%。     

Effect of disintegrated sludge recycling on membrane permeability in a membrane bioreactor combined with a turbulent jet flow ozone contactor

We have combined a turbulent jet flow ozone contactor (TJC) with a membrane bioreactor (MBR) to establish a zero-discharge system in terms of excess sludge in the MBR. The TJC-MBR system was compared with the conventional MBR (Control-MBR) with respect to i) the size and zeta potential of the sludge particles, ii) the loosely bound extra-cellular polymeric substances (EPSs) and tightly bound EPS of the microbial flocs, iii) the porosity and biovolume of the bio-cake accumulated on the membrane, and iv) the membrane permeability. The TJC system generated the ozonated sludge with a negligible amount of loosely bound EPS and a positive zeta potential. As a result, when such ozonated sludge was recycled, the average size of the sludge particles (e.g., microbial flocs) increased in the TJC-MBR. Consequently the bio-cake formed in the TJC-MBR had greater porosity than that in the Control-MBR, giving rise to higher membrane permeability in the TJC-MBR.     

Is the association between temperature and mortality modified by age, gender and socio-economic status?

Background

A number of studies have examined the relationship between high ambient temperature and mortality. Recently, concern has arisen about whether this relationship is modified by socio-demographic factors. However, data for this type of study is relatively scarce in subtropical/tropical regions where people are well accustomed to warm temperatures.

Objective

To investigate whether the relationship between daily mean temperature and daily all-cause mortality is modified by age, gender and socio-economic status (SES) in Brisbane, Australia.

Methods

We obtained daily mean temperature and all-cause mortality data for Brisbane, Australia during 1996-2004. A generalised additive model was fitted to assess the percentage increase in all deaths with every one degree increment above the threshold temperature. Different age, gender and SES groups were included in the model as categorical variables and their modification effects were estimated separately.

Results

A total of 53,316 non-external deaths were included during the study period. There was a clear increasing trend in the harmful effect of high temperature on mortality with age. The effect estimate among women was more than 20 times that among men. We did not find an SES effect on the percent increase associated with temperature.

Conclusions

The effects of high temperature on all deaths were modified by age and gender but not by SES in Brisbane, Australia.     

臭氧水浓度对鳙鱼头减菌效果及鲜度品质的影响

目的 研究不同浓度臭氧水对鳙鱼头减菌效果的影响,确定鳙鱼头最佳臭氧水减菌化条件,为鳙鱼头的冰温保鲜奠定基础。方法 采用气液混合法制备不同浓度的臭氧水,通过菌落总数及TBA值、TVB-N值、K值和pH值反映臭氧水浓度对鳙鱼头减菌效果的影响。结果 高浓度臭氧水能显著提高鱼头的减菌率、降低其TVB-N值和K值(p<0.05),对TBA值及pH值无显著影响(p>0.05)。淋洗时间对鳙鱼头的减菌率有显著影响(p<0.05),对其它指标无显著影响(p>0.05)。结论 用浓度为7.8mg/L臭氧水淋洗处理鳙鱼头5min,其减菌率可达到90.43%,且TBA值、TVB-N值和K值均较低,减菌效果较好。     

前途光明的臭氧漂白技术

本文介绍了臭氧漂白的漂白原理、发展过程及世界臭氧漂白的最新发展,展望了臭氧漂白的光明前景.     

臭氧和山梨酸钾对台湾青枣贮藏研究

臭氧是一种强氧化剂,具有广谱、高效的杀菌作用,能降解乙烯、乙醇等有害气体,较常用于果蔬上的保鲜。台湾青枣(ZizyphusmauritianaLam.)经臭氧和山梨酸钾处理后在常温下贮藏保鲜,结果表明处理2用3×10-6的臭氧处理后,台湾青枣果实的贮藏有较好的效果。试验结果显示提高了好果率,第6天处理2有一个峰值为15.34CO2mg/kg·h,呼吸强度高峰比其他处理低;延缓了果实硬度,减缓了Vc含量的下降,提高了超氧化物歧化酶的活性。     

新型橡胶防护蜡的开发与应用

介绍3种新型橡胶防护蜡XJL系列产品的开发及其应用性能。结果表明：在轿车子午线轮胎胎侧胶中加入新型橡胶防护蜡,硫化胶的物理性能变化不大,耐臭氧老化性能明显提高;当新型橡胶防护蜡用量为2份时,胶料成本较低和产品外观质量较好;10^#和30^#橡胶防护蜡的耐臭氧老化性能优于或相当于国内外同类产品。     

AO/MBR/臭氧氧化工艺处理制衣废水

对天津某制衣厂废水处理系统存在的水量和水质等问题进行调研分析,在充分利用原有处理构筑物和设备,同时利用厂区周围空地的前提下,采用AO/MBR/臭氧催化氧化工艺进行扩容和升级。工程运行结果表明,改造工艺经调试运行稳定,处理出水BOD5、SS、色度等达到《城市污水再生利用城市杂用水水质》(GB/T18920-2002)标准。