电-生物耦合技术对偶氮染料的去除研究

酸性大红GR是一种较难生物降解的偶氮染料,采用一种电场和生物耦合的新型技术处理酸性大红GR模拟废水,并与单纯电化学法和好氧生物法进行试验对照。结果表明：反应6 h后,电化学法、好氧生物法、电-生物耦合技术对酸性大红GR的去除率分别达到15.7%、25.8%和71.2%,电-生物耦合技术能明显提高酸性大红GR的去除效果,起到强化生物处理的作用。在15 mA微电流条件下电-生物技术能克服50 mg/L酸性大红GR对好氧生物处理的抑制作用,为高浓度难降解染料废水的生物强化处理提供了可能。     

预腐蚀条件下不同孔数冷挤压强化7075-T6铝合金板件疲劳寿命退化规律

目的 研究腐蚀环境下单孔和多孔冷挤压强化铝合金板件的疲劳寿命退化规律和损伤机理。方法 针对2种不同孔距的三孔冷挤压强化7075-T6铝合金板件,采用模拟热带海洋大气环境的实验室加速腐蚀谱,开展不同腐蚀时间下的预腐蚀疲劳试验。结果 获得了3倍孔距的三孔挤压强化铝板以及单孔挤压强化铝板的C(t)曲线、疲劳S-N曲线和损伤形貌特征,分析了腐蚀后挤压强化试件的腐蚀机理及挤压强化作用。同时,将不同孔数试件的试验结果进行比较,探明了孔数对挤压强化铝板腐蚀和疲劳性能的影响。结论 腐蚀后挤压强化铝合金板件的疲劳性能发生显著退化,腐蚀损伤主要为剥蚀,疲劳裂纹萌生位置由孔边转移至表面。挤压孔数量对挤压强化铝合金板件的疲劳和腐蚀疲劳性能的影响较小。     

浸水冷应激对雏鸡某些酶活性及消化道粘膜充血的影响

以海兰雄性雏鸡为试验对象,研究急性浸水冷应激对健康雏鸡某些酶活性消化道粘膜充血的影响。结果表明：雏鸡在浸水冷应激后血清肌酸激酶（CrK）呈一致性升高趋势;而丙氨酸氨基转肽酶（ALT）的活性则在冷应激后15min明显升高（P＞0.05）,而后降低,至120min时又恢复致冷应激前水平,雏鸡血清乳酸脱氢酶（LDH）在冷应激后15－60min呈渐进性升高,而后降低;血清γ－谷氨酰转肽酶（γ－GT）的变化趋势为,在冷应激后15min稍升高,而后则逐渐下降;血清尿素氮（BUN)的变化无是,在冷应激后60min降低,浸水应激后不同时间对海兰雏鸡消化道粘膜充血的结果表明：雏鸡在浸水应激后即刻观察造成消化道充血现象并不严重;而浸水应激后不同时间却对雏鸡消化道产生相对较强的影响,特别是冷应激后1－2h胃肠道充血比较严重。     

无机陶瓷膜处理冷轧厂乳化液废水工艺

通过对冷轧厂乳化液(含油)废水处理方法的对比,说明处理该废水采用无机陶瓷膜处理装置完全可行;介绍了无机陶瓷膜处理冷轧厂乳化液(含油)废水的工艺过程及处理系统组成。     

乌鲁木齐市一次冷空气过境天气对空气污染的影响分析

根据对2006年11月20～28日乌鲁木齐市出现冷空气过境天气过程的天气形式和主要气象要素及空气污染变化情况进行的分析,结果表明:冷空气过境天气前后,诸多气象要素发生了变化,冷空气导致逆温层的破坏和降水过程使各项污染物均得到有效的清除.通过此分析可为类似天气的空气质量预报提供思路.     

郑州园林绿化树木低温寒冻害空间分布特征研究

绿化树木是园林景观的主体部分,同样也是园林建设中的目标植物.然而,绿化植物容易受到低温寒冻害的影响,进而影响园林布局美观.基于此,该文提出郑州园林绿化树木低温寒冻害空间分布特征研究方法,统计郑州园林绿化树木类型,对各样本按照乔木层与灌木层进行分类整理,将频度、显著度、密度等作为计算树木多样性的指标,分析比较结果,根据获...     

TENMILE CREEK: A STUDY OF STREAM RELOCATION1

ABSTRACT: After input from various interested agencies, three miles of creek were relocated to facilitate the construction of Interstate 70 through Tenmile Canyon west of Denver. The 0.5.million dollar project was designed to provide fish habitat of equal value to that present before construction or, if possible, to improve this habitat. Construction techniques were designed to minimize damage to flora and fauna. After the channels were excavated, rock and log fish habitat structures were constructed. Two years after construction, a 4 percent chance flood occurred at the project area which made almost 75 percent of the habitat structures ineffective. Pool-riffle ratios and quantity and quality of spawning areas remained essentially unchanged throughout the period. Population estimates indicated an increase in the number of fish in the postconstruction period compared to preconstruction numbers. Fish biomass estimates for the project area were comparable for the two periods. Aquatic invertebrate populations were unchanged as indicated by comparison of three pre- and postconstruction indices.     

COLD-SHOCK RESISTANCE TO LARGEMOUTH BASS,BLUEGILL, AND CHANNEL CATFISH1

ABSTRACT: Juvenile specimens of largemouth bass, bluegill, and channel catfish were tested to determine their ability to withstand abrupt temperature decreases simulating the environmental impact from a sudden shutdown of a nuclear reactor during the winter. Temperature reductions were administered over 2-hour and 24-hour periods to assess the importance of the rate of temperature change and hence the mitigative value of having a holding pond with a one-day retention time between the proposed cooling tower discharge and the receiving stream. Temperature decreases administered over a 2-hour period resulted in much greater mortality than decreases of the same magnitude administered over a 24-hour period. Thus, the value of a pond for mitigation from cold shock was substantiated. Results also indicated that adherence to the U.S. EPA temperature criteria for freshwater fish should provide adequate protection from cold shock.     

连续退火机组氮气窒息事故分析及预防对策

介绍了某冷轧厂连续退火机组发生的一起氮气窒息事故,分析了水淬槽氮气产生的机理、事故发生的原因,提出了预防氮气窒息事故的对策措施.     

冷挤压工艺智能设计中的压力计算

冷挤压力的高低是冷挤压工艺成败的关键 ,通常挤压力计算是人工完成的。文中介绍了冷挤压工艺计算机智能设计系统中的挤压力计算及其参数优化部分的软件开发方法。该方法分别介绍了数据库设计、用户界面设计、挤压力计算、工艺评价等内容