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81.
A 12-month prospective population study of antenatal patients was undertaken in a large district general hospital to assess ultrasound scanning in late pregnancy for the detection of non-lethal fetal renal abnormalities. The rate of false-negative antenatal scans during the study period was also assessed. Both 18–20 and 28–32 weeks' gestational scans were performed on 6497 pregnant women. Forty fetuses with a suspected abnormality were referred for postnatal examination and 29 neonates were found to have renal abnormalities. Of these, 21 were significant and eight were likely to be extrarenal pelves. In six, there was evidence of an abnormality at the early scan. Nine children, seven with reflux, presented within the study period, all with preceding normal antenatal scans. The incidence (0·46 per cent) of structural renal abnormalities is similar to that reported previously. A late scan is necessary for the antenatal detection of non-lethal renal abnormalities.  相似文献   
82.
上海市生活垃圾的处理现状及对策探讨   总被引:6,自引:0,他引:6  
阐述了上海市目前生活垃圾收运及处理情况,对2000年上海生活垃圾的产量作了预测,对生活垃圾处理对策的分析中,提出技术,资金和管理等方面的支持条件。  相似文献   
83.
凡广生  李多松 《环境科技》2005,18(Z1):57-58
概述与分析了液膜分离技术,重点介绍了液膜法处理含酚废水、含(NH4)2S废水、含氰废水的工艺和方法.  相似文献   
84.
详细介绍了美国《城市生活垃圾填埋场标准》,德国《生活垃圾技术条例》,日本《废弃物最终处置场指南》和欧盟《废弃物填埋导则》等有关生活垃圾填埋污染控制的标准的主要内容以及其主要特点,并与中国现行的《生活垃圾填埋污染控制标准》(GB16889-1997)相比较,主要从选址、入场垃圾要求、渗滤液排放标准、防渗结构和终场覆盖系统等5方面分析了GB16889中存在的一些问题,并对今后其修订、完善工作提出了具体的建议.  相似文献   
85.
浦东新区生活垃圾焚烧厂工程实例   总被引:15,自引:1,他引:15  
依据浦东新区生活垃圾产量,组分及热值等,1998年底动工兴建日处理垃圾1000t规模的焚烧厂,占地8hm^2,工程总建筑面积22197m^2,投资估算66915万元,主要焚烧设备采用SITY-2000倾斜往复阶梯式机械炉排等,配置有3条生产线,2套8500KW的化电机组。  相似文献   
86.
城市生活垃圾(MSW)厌氧消化处理研究   总被引:6,自引:0,他引:6  
提出了城市生活垃圾的高固体含量厌氧消化处理方法并对此进行了研究。结果表明,城市生活垃圾的高固体含量厌氧消化处理是生活垃圾最好的处理方式之一,垃圾不仅可以得到即时即地的大量处理,最大限度地减少垃圾的污染,同时,还可以产生很好的经济效益和巨大的环境效益,这种垃圾处理方式值得应用和推广。  相似文献   
87.
三相生物流化床处理生活废水   总被引:3,自引:0,他引:3  
对三相生物流化床处理生活废水进行了实验研究,探讨了生物载体种类、溶解氧、水力停留时间及供气量对处理效果的影响。在选择的实验条件下,对进水CODcr值为600~1700mg/L的选定废水样,CODCr的平均去除率为85.8%。  相似文献   
88.
Routine surveillance of a large geographic region for clusters of adverse health events, particularly cancers, often involves small area health data, possibly controlling for exposure information. Many different methods have been proposed to test for the presence of geographical clusters. Two of the most popular methods are the spatial scan method proposed by Kulldorff and that using a fixed number of cases within scanning circles proposed by Besag and Newell. Although the second test is very popular, it has some difficulties. While the scan test controls for the multiple testing problem, the Besag and Newell test does not. Additionally, the latter method requires the setting of several tuning parameters whose values affect the test performance and are subjectively chosen by the user. This creates a difficulty to make a fair comparison between the two methods and it explains why there have been few formal studies evaluating their relative performances. In this paper, we modify the Besag and Newell test allowing for the control of the error type I probability and compare its power with respect to that of the spatial scan test. We used data sets from a publicly available simulated benchmark. We found that the two methods have similar results, except for clusters located in sparsely populated regions, where the spatial scan method presented a better performance.  相似文献   
89.
90.
The present investigation deals with an application of integrated sequential oxic and anoxic bioreactor(SOABR) and fluidized immobilized cell carbon oxidation(FICCO) reactor for the treatment of domestic wastewater with minimum sludge generation. The performance of integrated SOABR-FICCO system was evaluated on treating the domestic wastewater at hydraulic retention time(HRT) of 3 hr and 6 hr for 120 days at organic loading rate(OLR)of 191 ± 31 mg/(L·hr). The influent wastewater was characterized by chemical oxygen demand(COD) 573 ± 93 mg/L; biochemical oxygen demand(BOD5) 197 ± 35 mg/L and total suspended solids(TSS) 450 ± 136 mg/L. The integrated SOABR-FICCO reactors have established a significant removal of COD by 94% ± 1%, BOD5 by 95% ± 0.6% and TSS by 95% ± 4% with treated domestic wastewater characteristics COD 33 ± 5 mg/L; BOD59 ± 0.8 mg/L and TSS 17 ± 9 mg/L under continuous mode of operation for 120 days. The mass of dry sludge generated from SOABR-FICCO system was 22.9 g/m~3. The sludge volume index of sludge formed in the SOABR reactor was 32 mL/g and in FICCO reactor it was 46 mL/g. The sludge formed in SOABR and FICCO reactor was characterized by TGA, DSC and SEM analysis. Overall, the results demonstrated that the integrated SOABR-FICCO reactors substantially removed the pollution parameters from domestic wastewater with minimum sludge production.  相似文献   
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