Improved biogas production from rice straw by co-digestion with kitchen waste and pig manure

In order to investigate the effect of feedstock ratios in biogas production, anaerobic co-digestions of rice straw with kitchen waste and pig manure were carried out. A series of single-stage batch mesophilic (37 ± 1 °C) anaerobic digestions were performed at a substrate concentration of 54 g/L based on volatile solids (VS). The results showed that the optimal ratio of kitchen waste, pig manure, and rice straw was 0.4:1.6:1, for which the C/N ratio was 21.7. The methane content was 45.9–70.0% and rate of VS reduction was 55.8%. The biogas yield of 674.4 L/kg VS was higher than that of the digestion of rice straw or pig manure alone by 71.67% and 10.41%, respectively. Inhibition of biogas production by volatile fatty acids (VFA) occurred when the addition of kitchen waste was greater than 26%. The VFA analysis showed that, in the reactors that successfully produced biogas, the dominant intermediate metabolites were propionate and acetate, while they were lactic acid, acetate, and propionate in the others.     

巴东官渡汇流口网箱养鱼对附近水域水质的影响

对巴东官渡汇流口网箱养殖区进行了现场调查和实验室分析，结果显示其水质变化规律为网箱养殖区劣于控制断面区域，控制断面劣于背景和削减断面，同一断面水质基本相同，控制断面水质由网箱向外逐渐变好。主成分分析表明，不同养殖区对水体污染影响依次为：中华鲟养殖区>鸭嘴鲟养殖区>黄颡鱼养殖区>鲤鱼、草鱼混养区。各水质指标相关性分析表明，官渡Chla与总磷和氨氮高度相关；氨氮、总氮、总磷和高锰酸盐指数4个指标明显相关，说明其污染源具有同源性，该水域污染主要受到网箱养殖的影响。以超河流背景断面浓度5％作为划定超背景污染带的标准，网箱养鱼引起的氨氮超背景污染面积最大，约为网箱面积的10倍，高锰酸盐指数超背景污染面积最小，约为网箱面积的5倍     

浸水条件下环氧微表处与沥青路面层间抗剪性能的试验研究∗

微表处在工程应用过程中受水与车辆荷载作用,容易产生推移或整片剥落。为此,在微表处中添加适量不同种类的水性环氧树脂(Water-borne Epoxy Resin,WER)形成环氧微表处,通过拉伸试验和自主设计的45°斜剪试验,研究WER对环氧微表处在浸水条件下层间抗剪性能的影响。试验结果表明:胶结料在掺入刚性较大的WER后,随浸水时间增加,胶结料塑性变形能力削弱,弹塑性阶段与塑性阶段减短,脆性增加,而掺加柔性的WER,塑性阶段持续时间较长;浸水状态下,环氧微表处与沥青路面的层间抗剪强度影响因素主次顺序为油石比WER掺量WER掺加方式,而切向变形率的影响因素主次顺序为WER掺量WER掺加方式油石比。在工程应用中,建议采用油石比7%、WER掺量8%～12%且将环氧树脂与固化剂预先调和后加入水中,然后与集料进行拌合。     

关于日本钢铁炉渣的回收再利用

钢铁炉渣具有环保节能的特性,可以减少对环境的损害,因而被认作是一种可回收再利用的材料,按照其特有的性质,可用于许多领域,例如水泥、混凝土骨料、地基改良材、道路、肥料和石棉等。本文简要介绍了日本钢铁炉渣回收再利用情况。     

Performance and Microbial Characteristics of Bioaugmentation Systems for Polyacrylamide Degradation

Efficient and reliable removal of polyacrylamide (PAM), which are present in oil extraction waste water, is critically important to prevent toxic discharges to receiving waters. In the present study, two PAM degrading bacterial strains, namely HWBI and HWBIII, were isolated from the activated sludge and soil in an oil field. Two sequencing batch reactors (SBRs) were bioaugmented with either HWBI or HWBIII and the performance of each bacteria for enhancing PAM removal was compared. The effects of bioaugmentation on the performance of the SBRs with different exogenous strains after a single inoculation were investigated under long term operation. Results showed that for the SBR augmented with HWBI, 70% of PAM was removed at the end of the first operation cycle, and the removal remained at approximately 70% in the following eight cycles after a single inoculation. For the SBR augmented with HWBIII, only 45% of the PAM was removed in the first cycle after the inoculation, and PAM removal decreased to 30% after eight cycles. Terminal restriction fragment length polymorphism (T-RFLP), a molecular screening technique, was applied to track the supplemented bacterial strains and to evaluate the effects of bioaugmentation on the microbial communities and to investigate the optimal bioaugmentation strategy.     

鞋类防滑性能实验方法的研究

本文通过两种鞋类防滑性能的测试方法,测定不同材料、不同路面、不同湿度的动摩擦系数来对鞋类防滑性能进行研究.对于不同的测试对象探索不同的测试条件和评定标准,从而可以获得科学准确适应面广的研究成果.     

赣州市供销社系统再生资源网络体系建设

为充分发挥供销社服务"三农"的作用,赣州市供销社加快推进供销社系统再生资源网络体系建设步伐,对赣州市供销社系统再生资源网络体系建设的基本情况、主要工作及存在的问题进行论述,并提出主要对策及建议。     

环鄱阳湖区32城市的等级结构与空间关联研究

通过分析城市等级结构和空间关联，有助于识别城市体系发展阶段和协作状况，对于指导区域城市协调发展具有重要的意义。以环鄱阳湖区32城市为研究对象，运用“位序 规模”法则分析后发现：2006年环鄱阳湖区中间位序城市较多，人口分布较为均衡，但研究区的2城市指数高达3.698，南昌市的首位优势十分明显；运用“区域经济联系量”分析南昌市区与其它31城市间经济联系隶属度，结果表明研究区内二级城市中九江、抚州隶属度较高，三级城市中星子、湖口、彭泽和浮梁的隶属度较低。因此，为促进环鄱阳湖区城市群的协调发展，应重点加强二级城市的城市化建设，如九江、新余，促进各级城市间的经济协作。     

微孔分布器对光催化臭氧氧化反应器传质的影响

为了开发高效的光催化臭氧氧化反应器,以不同孔径钛微孔气体分布器对臭氧气液传质性能进行了研究.考察了表观气速和表观液速对液相总传质系数的变化影响规律,获得了液相总传质系数与表观气速的关联公式和微孔板孔径与表观气速对液相总传质系数的经验关联公式.利用无因次吸收数对微孔分布器的性能进行了分析,得到不同表观气速下微孔分布器的性...