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The appearance of excessive lipids in amniotic fluid during Caesarean section raised the suspicion of a hyperlipidaemic fetus. The amniotic fluid had elevated cholesterol (53 mg/dl) and triglycerides (81 mg/dl). At the age of 2 months, the infant was hyperlipidaemic (cholesterol of 161 mg/dl and triglycerides of 84 mg/dl). The case suggests the possibility of prenatal diagnosis of hyperlipidaemia, a major risk factor for atherosclerosis. 相似文献
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Mr. M. T. Rebello C. T. H. Gray D. E. Rooney J. H. Smith G. A. Hackett F. E. Loeffler D. H. Horwell R. W. Beard D. V. Coleman 《黑龙江环境通报》1991,11(1):35-40
One hundred and fourteen samples of amniotic fluid taken before 15 weeks of gestation were cultured for cytogenetic studies. The results of culturing these early amniotic fluid (EAF) samples were compared with the results of culturing 114 standard amniotic fluid (SAP) samples taken after 15 weeks of gestation matched for maternal age and received in the laboratory within the same week. Cell culture was successful in all 114 of the EAF samples and in 111 SAP samples. There was no significant difference in the days to harvesting and days to reporting in the two groups. Three samples of SAP failed to grow and two EAF samples produced tetraploid karyotypes, so that in these five cases amniocentesis had to be repeated. These problems were attributed to toxicity of a fungicide used in the culture medium. Pseudomosaicism was noted in two EAF samples and one SAP sample; and maternal cell contamination was noted in one EAF and one SAP sample. Thus, culturing and karyotyping cells harvested from EAF and SAP are similar, indicating that EAF samples from 12–14-week pregnancies could be used for prenatal diagnosis. 相似文献
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目的 适配发射过程无火药气体且弹丸不自旋的电磁发射技术,设计一种直接由空气作用的张开式尾翼。方法 该尾翼预制斜角,通过进气道气流在斜面上产生的压差,推动尾翼绕螺钉打开。采用动网格技术耦合流体控制方程、六自由度(6DOF)方程,对不同马赫数下尾翼张开过程进行仿真。结果 设计的空气作用张开式尾翼在流场作用下可以正常张开,来流流速为2、3、4马赫时,张开耗时分别为4.7、3.7、3.1 s。结论 该空气作用张开式尾翼方案设计有效。马赫数越高,张开过程耗时越短。迎风面积显著影响尾翼张开过程。 相似文献
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基于随机多层纤维过滤介质算法建立了平板式三维拟态化结构.利用计算流体力学-颗粒群平衡模型(CFD-PBM)对多纤维捕集过程中细颗粒湍流团聚进行数值模拟研究,并采用分区法求解颗粒群平衡方程(PBE).通过控制变量法分析表明:多纤维捕集过程中存在着明显的颗粒团聚行为.粉尘颗粒的团聚程度随停留时间增加而增强,当t ≥ l/v(速度方向模型尺寸长度/入口风速),团聚逐渐趋于稳定;当vmax·t ≤ l,入口风速越大,颗粒团聚程度和团聚速率越大,最终的团聚程度取决于入口风速和停留时间;颗粒粒径越大,粉尘颗粒的团聚程度和团聚速率越小.出口颗粒平均粒径与初始粒径相比增长倍数越小.粉尘颗粒体积分数越大,颗粒团聚程度以及团聚速率越大.当v=0.1m/s,dp=1.0μm,VF >0.003636,Bin-7~Bin-0区间数量浓度对数分布呈线性比例关系. 相似文献
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Although the diffusion of its storage and transport under liquefied conditions, nowadays it is common to have methane in gaseous form in several industrial applications. This leads to safety implications to be considered: hazards are linked to both the high-pressure at which the gas is kept and to its flammability. Scenarios where flammable jets impact an obstacle are of paramount importance because of their possible occurrence. Following a numerical approach, literature shows up that their assessment can be reliably performed by means of only Computational Fluid Dynamics tools. However, despite the improvements of computing power, Computational Fluid Dynamics costs still limit its use in daily risk analysts’ activities. Therefore, considering an accidental jet-obstacle scenario of industrial interest, the present work investigates how a pipe rack can influence the development of a high-pressure methane jet. Based on a Computational Fluid Dynamics analysis, main achievements of this work are a simple criterion able to identify the situations where the pipe rack does not influence the high-pressure methane jet behavior, therefore allowing to identify the scenarios where simpler models can be used (i.e., analytical correlations known for the free jet situation), and, if present, a simple analytical relationship that roughly predicts the influence of the pipe rack without the need of performing complex Computational Fluid Dynamics simulations. 相似文献
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废弃油基钻井液是钻井作业完成后产生的固体废物,因含有矿物油和柴油等,属于国家危险废物,成为制约油田清洁生产的一个技术难题.针对废弃油基钻井液的特点,经大量室内试验和多种处理方案的筛选,开发出了废弃油基钻井液资源回收与无害化处置技术.在废弃油基钻井液中加入收油剂,回收有用的油类.在收油后的剩余泥渣和产生的废水中分别加入无害化处理剂和絮凝剂,进行回用和无害化处理.油回收率可达90%以上,回收的油品质量达到《车用柴油》(GB/T 19147—2003)规定的-10#车用柴油技术要求;无害化处理后的泥渣浸出液中石油类,CODCr和重金属等污染物指标均低于《污水综合排放标准》(GB 8978—1996)二级标准限值;处理后的废水达到《污水综合排放标准》(GB 8978—1996)要求. 相似文献
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