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361.
通过洗煤车间除尘系统工程实例 ,阐述了在老厂房巧妙利用厂房结构 ,将吸尘罩设计为内开外密 ,负压作业的三级密闭形式 ,从而实现全面通风换气与局部通风除尘的设计思路。工程实践表明 :该设计可使尘源附近 (411机尾走廊 )空气中粉尘净化效率达到 81 16 %~ 94 93% ,对厂房主要作业点空气中粉尘净化效率达 6 0 %以上 ,为洗煤行业老厂房的防尘除尘工作探索了一条可行的途径 相似文献
362.
跌水曝气——改进型填料(滤料)排水系统处理屠宰废水的设计 总被引:7,自引:0,他引:7
对屠宰厂原有的排水管道系统进行改造和革新 ,使之成为沉淀、厌氧好氧生物接触氧化与过滤的新型排水系统 ,用于屠宰废水处理 ,实现了达标排放 相似文献
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LAO Shan-gen 《环境科学学报(英文版)》2002,14(1):132-135
IntroductionBeforethe 1 980sconventionaltreatmentprocessesofphenolswastewateraresolventextraction ,physicaladsorption ,chemicaloxidationandaerobicbiologicalprocess.Amongthebiologicalunitprocessesactivatedsludgeprocessismainone.Afterthe 1 980sanaerobicbiologic… 相似文献
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B. N. Chodirker M.D. A. E. Chudley K. M. Macdonald C. R. Harman J. A. Evans 《黑龙江环境通报》1994,14(11):1086-1089
This study was undertaken to evaluate the relationship between maternal serum alpha-fetoprotein (MSAFP) levels and oesophageal atresia (OA). OA occurred in 16 fetuses of mothers who had an MSAFP test in the study interval. The multiple of the median (MOM) value for MSAFP averaged 1·54 ± 0·65 (range 0·5–2·9 MOM), which was significantly higher than the value seen in controls. The median MOM was 1·35. Using a cut-off of 2·5 MOM, the sensitivity of MSAFP for detecting OA was 19 per cent. Although OA should be considered in the differential diagnosis of an elevated MSAFP level, MSAFP cannot be considered an appropriate screening test for OA given the low sensitivity. 相似文献
369.
A stopped-flow reversed flow injection method for the determination of free cyanide is proposed. Pyridine-barbituric acid mixture is injected in the flow system as reagent to form the colour species with cyanide. The flow is stopped when the reagent zone comes in the flow cell, where absorbance-time data are collected at 580nm wavelength. The linear range of the determination is 0.1 -10μg/ml CN-. The sampling rate is 60h-1 and the relative standard deviation is 1.6% (n=16) at 5.0 μg/ml CN-1 level. With satisfactory results, the proposed method was applied to the determination of free cyanide in wastewater without sample pretreatment. 相似文献
370.
William D. Boelter MD Beth Ann Burt Elaine B. Spector David R. Hinton Zdena Pavlova Atsuko Fujimoto 《黑龙江环境通报》1990,10(11):703-715
A pregnant woman with indeterminate Duchenne muscular dystrophy (DMD) carrier status, but with DMD diagnosed in her deceased brother (unavailable for study), presented for prenatal diagnosis, intending to continue the pregnancy only if proven unaffected with DMD with near absolute certainty. Creatine kinase (CK) assays to clarify carrier status were inconclusive. Male sex in the fetus was identified, but DNA restriction fragment length polymorphism (RFLP) analysis was not yet available to this centre to investigate the possible transmission of the DMD gene, and the pregnancy was terminated. Tissue histology and dystrophin protein analysis demonstrated the absence of DMD. In a situation with proven maternal carrier status, future fetal inheritance of the opposite maternal X chromosome would indicate the presence of DMD. However, maternal carrier status remained in doubt through a second pregnancy, even with RFLP studies, and was finally established when dystrophin analysis confirmed the presence of DMD in the second fetus. Histologic findings are presented, contrasting features in the two fetuses. The value of dystrophin analysis for establishing the diagnosis of fetal DMD, in this case proving maternal carrier status in a difficult situation, and for demonstrating DMD gene:RFLP haplotype relationships is illustrated. 相似文献