Nitrogen removal using recycled polystyrene bottles as biofilm media

The performance of an attached growth wastewater treatment process was investigated in an effort to improve nitrogen removal efficiency. Recycled Yakult (lactic acid fermentation drink) bottles made of polystyrene were used as a biofilm media. The use of Yakult bottles as a biofilm media has been attempted by numerous researchers in Japan for the removal of solids and organics. However, these studies focused only on the removal of solids and organics. This study extended their application to the removal of nitrogen for domestic sewage treatment. Yakult media was placed in a reactor with 70% apparent reactor volume in a conventional A/O process. The bottom of the Yakult media was removed, and randomly filled Yakult media were effectively able to reduce the flow in tanks, resulting in an increase in the contact time between pollutants and microorganisms. With higher HRT, the nitrogen removal efficiency was increased by up to 83% with 12 hr of HRT. Nitrification appeared to be the limiting factor of nitrogen removal at an HRT that is less than 12 hr, indicating that the Yakult process requires more retention time to achieve nitrification compared to other biofilm processes. The removal efficiencies of organics and solids were high regardless of the change of operational parameters. This article is based on a presentation in “The 7th Korea-China Workshop On Advanced Materials” organized by the Korea-China Advanced Materials Cooperation Center and the China-Korea Advanced Materials Cooperation Center, held at Ramada Plaza Jeju Hotel, Jeju Island, Korea on August 24–27, 2003.     

Electrochemical properties of some cobalt antimonides as anode materi-als for lithium- ion batteries

Some cobalt antimonides have been prepared and studied as the candidate anode materials for lithium ion batter-ies. Reversible capacities of 424,423 and 546 mA·h·g-1 were measured at the first cycle for as-solidified CoSb2, CoSb3 and annealed CoSb3 respectively. A low lithium ions diffusion coefficient in the order of 10-16 m2·s-1 was estimated from the coulometric titration measurements in the annealed CoSb3 electrode. It was found that the electrochemical properties of fine powders are significantly better than coarse powders. However the SEM picture shows that the nano-sized CoSb3 powders gathered to larger granules, which worsens somewhat the capacity retention of the nano-sized materials, although the volume capacities of the annealed and ball milled CoSb3 remain near twice of that of graphite after 50 cycles.     

易门铜业公司18kt／a粗铜及硫酸车间的技改工程

介绍了易门铜冶炼厂烟气制酸系统的技术改造工程.从工艺流程、设备复核、工艺参数、设备配置等方面阐述了技改的过程.     

钨钴硬质合金电化学蚀刻加工研究

对YG6硬质合金电化学蚀刻工艺进行了研究,提出了采用光致抗蚀剂作保护膜,在生成一定钝化膜的情况下进行电化学蚀刻的方法.在一定的蚀刻深度范围内,该工艺的可控性好、腐蚀区表面质量较好.     

真空水冷铜坩埚感应炉模糊控制专家系统的研究

研究真空水冷铜坩埚感应炉中模糊控制专家系统。阐述该炉控制系统复杂性 ,介绍模糊控制专家系统的主要结构和各主要部分的功能和一些算法     

粘土砂旧砂再生效果与其含水量的关系

在影响粘土砂旧砂再生效果的诸多因素中,旧砂中水分含量是最重要的因素。本文就水分含量对再生效果的影响规律、再生效果最佳的水分含量等进行了研究和分析,得出了如下结论:并非含水量越低再生效果就越好,而是存在一个去泥率低谷区;再生效果最佳的适宜水分含量为1～2%。     

含B2O3渣系的热力学计算模型

根据炉渣结构的共存理论和相图，推导了ＣａＯＢ２Ｏ３和ＦｅＯＦｅ２Ｏ３Ｂ２Ｏ３渣系的热力学计算模型。结果表明：（１）理论计算的ＣａＯＢ２Ｏ３渣系的作用浓度ＮＣａＯ及ＮＢ２Ｏ３与实测的活度ａＣａＯ及ａＢ２Ｏ３一致；（２）理论计算的ＦｅＯＦｅ２Ｏ３Ｂ２Ｏ３渣系的氧化能力ＮＦｅｔＯ与实测的炉渣ＦｅｔＯ的活度值相符合。这说明本文提出的热力学计算模型是合理的。     

施工环境下无线网络测试方案

专业无线网络测试方案,测试环境苛刻,测试技术复杂,不便于施工现场进行测试。为了快速定位施工现场无线网络的运行状态,通过对无线网络技术的深入了解,以具体项目为契机,以发现并解决无线网络出现的问题为目的,制定详尽的无线网络测试方案,得出无线网络测试结果,分析结果得出网络出现的问题并解决。     

焊接企业生产管理系统

通过对焊接企业的分析和总结,以 Oracle 为数据平台,运用面向对象的插件开发技术,设计、开发了焊接企业生产管理系统,以便对企业焊接生产线上所有物质、流程进行更精准的监控、管理,如对焊材、母材的管理等。同时,该系统集成了各种焊材的国家检验标准数据,并支持按企业特性进行修改,为质检人员制定标准提供便捷。