砼芯水泥土复合桩在基坑支护工程中的应用与研究

砼芯水泥土复合桩是一种新型的基坑支护方法,即在水泥土搅拌桩中插入钢筋混凝土预制小方桩,形成一种新的复合桩体,兼有受力和止水的双重作用,并采用两排中间用圈梁相连的门型结构提高了支护结构的受力特性。该支护方案在南京某深基坑工程中得到了成功应用。本文分析了该新方法的结构特点、简要介绍了其设计计算方法,并结合有限元数值模拟和实际的监测数据与排桩方案进行分析比较。研究结果表明,该新型基坑支护形式取得了良好的支护和经济效果,具有重要的应用前景。     

Simulation and Trend Analysis of the Water Quality Monitoring Daily Data in Nestos River Delta. Contribution to the Sustainable Management and Results for the Years 2000–2002

The transboundary River Nestos in the Balkan Peninsula is a surface water resource shared by Hellas and Bulgaria. The Public Power Corporation of Hellas (DEH) proceeded to the dams' construction of Thesaurus in 1997 and Platanovrissi in 2000, to satisfy the increased needs for power production and irrigation in the Regions of Eastern Macedonia and Thrace in the Hellenic Territory. DEH following the Ministerial Agreement of the Hellenic Parliament ‘`KYA 18492/19—09—1996’' funded a series of Research Projects concerned on the monitoring of the water quantity and quality data of Nestos from the Hellenic-Bulgarian borders to its estuaries in the Thracian sea. ‘`PERSEAS’' Research Group from Aristotle University of Thessaloniki, carried out the research, design, construction, installation, operation and maintenance of the ‘`R.E.MO.S.’' (Remote Environmental MOnitoring System) networks. Three REMOS networks have been installed in the areas of (a) the River Nestos deltaic channel, (b) Thesaurus dam-lake in the intramountainous valley and (c) Potamoi (Despat) and Pagoneri (Nestos) villages close to the borders between Hellas and Bulgaria. They record water level (H), water and air temperature (T), water conductivity (ECw), Redox potential (RP) and dissolved oxygen (DO) on a 24h basis, since the beginning of the year 2000. The research carried out in this paper, is focused on the REMOS station in the final course of Nestos in the deltaic area. The continuous monitoring and the data analysis yield useful results for the quality and quantity of the hydrologic regime of Nestos after the dams' construction, as well as for the trends detected of the quality parameters (ECw, RP and DO) and the water level, using the nonparametric Spearman's criterion. The best fitted model of time trend, for each variable, was chosen. The statistical sample of each one of the quality variables consisted of about 1000 values based on daily measures on a three years monitoring program (1/1/2000—31/12/2002). Further research and analysis for the other network stations of REMOS should provide useful results for the sustainable management of the transboundary River Nestos.     

中国雨日变化趋势的分形研究

利用1951-2002年中国752个台站的雨日资料,运用分形理论和R/S分析法,研究并预测了中国五大降水区年雨日的气候变化趋势.研究表明:中国五大降水区未来的年雨日变化趋势与过去50a的变化有着很好的自相似性.为了更深入研究雨日的未来的变化,设计了两项Hurst指数试验,用两项试验结果与年雨日年际变化趋势的对应关系来推断未来的变化趋势及其转折与突变.结果表明:中国五大降水区年雨日有着一致的减少趋势,但其变化呈现显著的地域分异特征.依照五大降水区的气候倾向率,西北区、西南区、青藏高原区、东部北方区、东部南方区未来平均每10a雨日减少分别为4.1d,11.4d,3.7d,6.8d和5.9d,其中西南区年雨日减少最多.期间,中国五大降水区虽有气候变化的转折,但不存在雨日气候变化的突变点.     

循环经济:可持续发展战略的新探索

从200多前的欧洲工业革命开始，随着人类社会的不断进步，经济发展与生态环境两者之间逐渐对立起来，由于过分偏重经济发展，轻视生态环境保护，出现了许多生态环境问题，给人类生活带来了许多不便。21世纪将是人类与自然和谐共生的时代，为了保持生活水平的不断提高和经济的可持续发展，实现生态保护与经济发展二者之间的平衡，循环经济的发展和循环型社会的建立日显重要。     

Effect of cycle time on biodegradation of azo dye in sequencing batch reactor

The effects of cycle time on the biodegradation of the azo dye remazol brilliant violet 5R (RBV-5R) were investigated in an anaerobic–aerobic sequencing batch reactor (SBR). System performance was determined by monitoring chemical oxygen demand (COD), color, anaerobic enzyme (azo reductase) and aerobic enzyme (catechol 2,3-dioxygenase), and aromatic amine concentration. SBR was operated in three different total cycle times (48 h, 24 h and 12 h), fed with a synthetic textile wastewater. In this study, the anaerobic period of SBR was found to allow the reductive decolorization of azo dye and the aerobic period was found to be effective on further COD removal after the anaerobic period. The percentage reductions in color by the anaerobic stage of the SBR were at 72%, 89% and 86% for the 24-h, 12-h and 6-h cycle times, respectively. Total COD removal efficiencies were over 75% for all operational conditions and about 70% of the COD removal was achieved in the first 3 h of anaerobic stages. During the decolorization of RBV-5R, two sulfonated aromatic amines (benzene-based and naphthalene-based) were formed and detected by HPLC. Aerobic phases of SBR with total cycle times of 48 h, 24 h and 12 h were able to remove benzene-based aromatic amines with removal efficiency of 64%, 92% and 89%, respectively. The results indicated that the best SBR performance in terms of color removal and aromatic amine degradation was achieved from total cycle time of 24 h.     

连云港市大气污染物时间序列的长程相关性分析

运用R/S分析(Rescaled Range Analysis)方法对连云港市3个大气环境定位监测点近10年来的SO2、NOx和TSP序列数据进行了时间序列的长程相关性分析.结果表明,连云港市SO2、NOx和TSP月均值序列的Hurst指数在0.500～1.000,表现出明显的长程相关性,并且这种相关性程度的强弱随着城市功能区的不同而表现出一定的差异.研究结果对于认识连云港市城市大气环境质量变化过程和科学制定环保决策具有重要意义.     

青白江区农业废弃物循环利用产业链构建研究

阐述了循环经济、生态农业的内涵，分析了青白江区构建农业废物流动利用链的必要性，并以循环经济理论为指导，以实现物质与能量利用最优化为目的，利用3R原则，对该区进行农业废物流动链构建研究，使在农业生产过程中和产品生命周期中减少自然资源、物质的投入量和废物的排放量，实现“投入品－产出物－废弃物”的循环综合利用。     

我国生产安全事故的R/S分析

R/S分析方法是一种检验时间序列服从独立随机分布假设或非线性特征的有效工具.本文应用R/S分析方法实测了几类全国安全生产事故Hurst指数,表明几类全国安全生产事故发生具有持续性的特点,研究成果对于指导政府、企业认识安全生产规律,科学决策具有参考意义.     

酵母菌与两种硫杆菌复合对污泥中三价铬的去除

研究了氧化亚铁硫杆菌LX5(Thiobacillus ferrooxidans LX5)、氧化硫硫杆菌TS6(Thiobacillus thiooxidans TS6)和耐酸性酵母菌R30(Rhodotorula sp.R30)对重金属铬(Cr³⁺)的耐受性.结果表明,700mg/L的Cr³⁺对硫杆菌LX5、TS6的生长和氧化活性影响不大,但Cr³⁺浓度大于500mg/L时明显抑制酵母菌R30的生长.酵母菌R30与硫杆菌LX5和TS6复合能明显加速污泥淋滤的进程,最佳复合比为酵母菌R30接种量2.0%,硫杆菌LX5和TS6接种量10%.分别用含酵母菌R30数量为10⁴个/mL和102个/mL的酸化污泥作接种物进行污泥淋滤,发现淋滤过程中pH值下降的速度没有明显差异,而在淋滤起始时添加2.0%的酵母菌R30,则淋滤反应提前36h结束.由此可见,在其它条件相同的污泥淋滤中,污泥中所含耐酸性酵母菌的数量是加快淋滤的关键.