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Dr Etan Z. Zimmer Moshe Bronshtein Ela Ophir Israel Meizner Ron Auslender Gabriel Groisman Hava Meyer 《黑龙江环境通报》1993,13(6):503-511
Five fetuses with congenital cataracts diagnosed in utero by ultrasound are reported. The fetuses, who were between 14 and 27 weeks' gestation, also had other severe malformations. The sonographic features of the cataracts are presented. 相似文献
634.
Ultrasonography was performed during the second trimester (17 weeks) in a pregnancy at risk for osteogenesis imperfecta congenita (OI). The scan showed that the femur was short, bent and dense. Radiologic examination of the fetus after interruption of pregnancy showed typical X-ray changes of OI. 相似文献
635.
IntroductionHydrolysisisthereactionofchemicalswithwaterandalsoanimportantenvironmentalprocessoforganicpollutants.Hydrolysisofsyntheticorganiccompoundsoccursviaseveralpathwayswhichinvolvethespecific acid , baseandneutralprocesses.Inaddition ,waterdissocia… 相似文献
636.
IntroductionThebrassylicacidmanufacturingwastewatercontainshighchemicaloxygendemand(COD)concentration3000—12000mg/LanditsBOD5/CODisamong04—05Meanwhilethewastewatercontainshighsulphateconcentrationabout13000mg/LanditspHvalueisonly1—2Achemicalcompanyappliedneutrali… 相似文献
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The major issues in water and wastewater industry are to meet quality requirements, to guarantee treatment process efficiency, to contain investment and operating costs. This implies the use of powerful predictive modeling and simulation tools which are able to account for the multiple interaction between all the water quality and process design parameters. Computational Fluid Dynamics modeling tools have already been widely used in other industries but their application in water industry is quite recent. This paper presents different applications of CFD modeling to the study of the hydro-dynamic and mass transfer performance of single- or two-phase flow reactors used in water and wastewater treatment. Numerical simulations, together with experimental measurements, have been performed on laboratory and full-scale plants in order to gain a better under-standing of the physical phenomena (mixing, interfacial transfer) occurring in these systems. Numerical simulations are systematically validated by experiments. The paper shows how CFD can be helpful in order to improve the design of existing water treatment plants and the process efficiency. In this scope, CFD enables designs more reliable and cost effective water treatment processes which remain basic environmental policy issues. 相似文献
639.
Kinetic processes of alpha-naphthaleneacetic acid (NAA) photolysis were studied under different conditions. The results showed that the ultraviolet light was more effective than fluorescent light in promoting degradation, and the degradation of NAA under ultraviolet light followed the first order kinetics with the photolysis rate constant of 1.15 x 10(-2) min-1 and half-life time (t1/2) of 60 min. Further, it was proved that the photolysis rate was higher in the presence of oxygen, titanium dioxide (TiO2), and low pH (acidic solution). At last, two photolysis intermediates were identified by GC-MS and possible photolysis pathways were proposed. 相似文献
640.