Nutrient removal performance of an anaerobic–anoxic–aerobic process as a function of influent C/P ratio

The laboratory scale anaerobic–anoxic–aerobic (A²O) process fed with synthetic brewage wastewater was designed to investigate the effects of changing feed C/P ratio on the performance of biological nutrient removal (BNR) processes. In the experiment, the influent chemical oxygen demand (COD) concentration was kept at approximately 300 mg L^?1 while the total phosphorus concentration was varied to obtain the desired C/P ratio. Results showed that when the C/P ratio was lower than 32, phosphorus removal efficiency increased as C/P ratio increased linearly, while when the C/P ratio was higher than 32, the P removal efficiency was maintained at 90–98%, and effluent P concentration was lower than 0.5 mg L^?1. However, regardless of the C/P ratio, excellent COD removal (90% or higher) and good total nitrogen removal (75–84%) were maintained throughout the experiments. It was also found that very good linear correlation was obtained between COD uptake per unit P released in the anaerobic zone and C/P ratio. In addition, the P content in the wasted activated sludge increased with the decrease in the C/P ratio. Based on the results, it was recommended that the wastewater C/P ratio and its effects be incorporated into BNR design and operational procedures, appropriate C/P ratios were used to achieve the effluent treatment goals. Copyright © 2005 Society of Chemical Industry     

Flows in rectangular microchannels driven by capillary force and gravity

Capillary phenomena was studied and discussed by the scholars about 200 years ago, but the progress was slow due to the limited equipment and manufacture precision of the microchannel. In recent years, because of the rapid development of MEMS and micromachining, many applications of the capillary flow is widely developing in some modern processes, such as underfilling of flip chip, flow in microfluidic chip or biochip, and a variety of other fields.     

如何又好又快地完成水利统计任务

1.依法进行统计是统计工作的根本 《中华人民共和国统计法》的颁布实施为统计工作提供了有力的法律保证,它明确了部门统计的合法性、必要性,明确了其责任、权力和义务。统计工作必须在统计法允许的范围内开展。设置统计机构,配备统计人员,确定统计任务,制定统计报表制度,进行各项统计调查,确定具体的统计指标等,都必须遵循这一原则。[第一段]     

HTR-10燃料元件装卸系统冷态调试

10MW高温气冷实验堆（HTR－10）是一座球床堆，由燃料元件装卸系统实现燃料元件的装卸和循环，且不需要停堆，为保证HTR－10的正常运行，燃料元件装卸系统必须安全，可靠，为此，必须对燃料元件装卸系统进行周密，细致的调试试验和验证，本文介绍了燃料元件装卸系统冷调试的主要调试项目，调试方法和调试结果。     

高职学院创建学习型组织的策略

高职学院创建学习型组织事关高职学院建设发展大局,创建学习型组织是一个持续不断的长期的过程,它需要高职学院按照彼得·圣吉提出的"五项修炼"加以逐步落实,确立新的学习理念,建立起能促进终身学习、全员学习、共同学习的体制、机制和知识共享平台。     

论如何有效控制水工混凝土施工的质量

该文从控制原材料、混凝土配制及对工地试验的监督等方面论述了如何控制混凝土施工的质量，并结合实践经验，分析了决定混凝土质量的主要因素，提出有效的预防措施。     

臭氧氧化-光催化降解水中的五氯酚

利用臭氧氧化-光催化技术降解水中的有机污染物五氯酚(PCP)。对比了紫外光照射、臭氧氧化、光催化、臭氧氧化-光催化4种方法降解PCP的情况。考察了臭氧氧化-光催化体系中臭氧流量、臭氧产量、PCP初始质量浓度、pH和CO23-等因素对PCP降解率的影响。实验结果表明,臭氧氧化-光催化法比单独使用紫外光照射、臭氧氧化、光催化法更能有效的去除PCP;增加臭氧流量和臭氧产量有利于提高PCP的降解率;降低PCP的初始浓度,PCP的降解率显著提高;pH对PCP的降解效果影响不明显;CO23-的存在显著降低了PCP的降解率。在臭氧氧化-光催化体系中,除臭氧直接氧化降解PCP外,臭氧与TiO2协同作用产生的.OH对PCP的降解也起到了重要作用。     

ABB变频器在双馈发电机试验台上的应用

本文介绍了风力发电系统目前存在的技术方案，重点介绍了ABB用于双馈式风力发电系统的变频产品ACS800—67的特性，并对由其构建的发电机测试平台的案例进行了实验分析。     

High-yield synthesis of single-crystalline 3C-SiC nanowires by a facile autoclave route

Single-crystalline 3C-SiC nanowires have been synthesized in large scale through a one-step autoclave route by the reaction of SiCl₄, (C₅H₅)₂Fe and metallic Na at 500 °C. Electron microscopy investigations show that the nanowires have typical diameters of 15-50 nm, lengths up to several tens of micrometers and grow along the [111] direction. The possible growth mechanism of the nanowires is discussed.