Aseptically collected calf serum as an effective alternative to fetal calf serum in the culture of amniotic fluid cells

The growth-promoting activities of three different bovine sera have been compared in primary and secondary amniotic fluid cell cultures. In secondary amniotic fluid cell micro- cultures, aseptically collected calf serum (CS) was slightly, though not significantly more effective than fetal calf serum (FCS) in promoting DNA synthesis, while newborn calf serum (NCS) was significantly less effective than either CS or FCS. All three sera were optimally effective at concentrations of 10 per cent (v/v). Significant variation in quality occurred within four batches of each of CS and FCS, but not within four batches of NCS. A selected batch of CS was significantly more effective in promoting the growth of primary amniotic fluid cell cultures than were a number of batches of FCS then in routine laboratory use. It is suggested that CS may serve as an effective and economical alternative to FCS in the culture of amniotic fluid cells, thereby expanding the scope of serum batch testing. A possible explanation for the varying growth-promoting activities of different sera is discussed.     

Unexpected structural chromosome rearrangements in prenatal diagnosis

Among 5315 prenatal diagnoses performed for various indications (maternal age, neural tube defect, metabolic diseases, X-linked diseases, pathologic pregnancies) 29 unexpected structural chromosome rearrangements were found in fetal cells. Fourteen were de novo chromosome rearrangements, six unbalanced, and eight balanced. Fifteen were inherited and balanced rearrangements. This high frequency of structural anomalies is discussed.     

废钻井液、泥浆的处理与控制对策

介绍中原油田分公司实施源头控制,减少废钻井液产生和利用无害化技术处理钻井废弃泥浆的实践,分析存在的主要问题,提出减少废钻井液产生的控制对策.     

一种高效节能的生物三相流化床技术

将竖流式生物三相流化床改为封闭卧式生物三相流化床后 ,不但保留了竖流式生物三相流化床原有的优点 ,消除了竖流式生物三相流化床存在的一些缺陷 ,而且又新增了功能 ,特别是电耗下降近 4 0 %。并着重介绍封闭卧式生物三相流化床在地下车库或其它对高度有限制场所的应用实例。该设备在处理餐饮业废水和一些中、小型工业有机废水中有较高的推广价值。     

南京及邻近地区新近沉积土的动剪切模量和阻尼比的试验研究

通过对南京及其邻近地区漫滩相成因的粘土、粉质粘土、淤泥质粉质粘土、粉质粘土与粉砂互层土、粉土、粉细砂等 6类新近沉积土的自振柱试验 ,详细探讨了围压大小、剪应变水平、土的颗粒组成和结构性对这 6类新近沉积土的剪切模量G及阻尼比λ的影响。通过与Seed和Idriss建议的砂土G/Gmax～γ和λ～γ曲线变化范围的对比 ,结果表明 ,不能将粉质粘土与粉砂互层土简单地当作砂土或粉质粘土对待。通过试验和理论分析 ,给出了南京及其邻近地区 6类新近沉积土动剪切模量和阻尼比随剪应变变化的平均曲线的拟合曲线、包络线及其参数的推荐值 ,对实际工程具有一定的借鉴作用     

沥青涂层对桩侧摩阻力影响的试验研究

采用改进直剪仪模拟桩与土之间的滑动摩擦,研究了沥青涂层对桩侧摩阻力的影响。试验结果表明,桩侧摩阻力与土的类型、法向应力有关,随着法向应力的增长,滑动摩阻力也相应增长,且增长近似呈线性关系;在一定的法向应力下,沥青涂层对减小滑动摩阻力有一定的作用,随着法向应力的增长,沥青涂层亦会导致滑动摩阻力增加。     

隧道救援站通风网络优化设计及人员疏散研究*

为确定铁路隧道救援站最佳通风结构，对烟道布置提出合理建议，采用计算流体力学（CFD）的方法，对铁路隧道救援站通风网络进行优化设计。同时，采用模拟计算的方法对救援站人员疏散进行模拟分析，确定救援横通道布置及防护门开度设置的合理性。研究结果表明:在同等通风参数工况设置下，采用多节点排烟竖井结构后各救援横通道流量分配更均匀，救援站压力平衡性更好，通风效率可提升15%；通过疏散模拟证实，在长560 m的紧急救援站范围内设置10条疏散横通道，横通道设1.7 m宽的逃生门能够满足疏散要求。     

Recent application of Computational Fluid Dynamics (CFD) in process safety and loss prevention: A review

In recent years, significant progress has been made to ensure that process industries are among the safest workplaces in the world. However, with the increasing complexity of existing technologies and new problems brought about by emerging technologies, a strong need still exists to study the fundamentals of process safety and predict possible scenarios. This is attained by conducting the corresponding consequence modeling and risk assessments. As a result of the continuous advancement of Computational Fluid Dynamics (CFD) tools and exponentially increased computation capabilities along with better understandings of the underlying physics, CFD simulations have been applied widely in the areas of process safety and loss prevention to gain new insights, improve existing models, and assess new hazardous scenarios. In this review, 126 papers from 2010 to 2020 have been included in order to systematically categorize and summarize recent applications of CFD for fires, explosions, dispersions of flammable and toxic materials from accidental releases, incident investigations and reconstructions, and other areas of process safety. The advantages of CFD modeling are discussed and the future of CFD applications in this research area is outlined.     

Numerical simulation of small-scale pool fires of LNG

Liquefied natural gas (LNG) has been largely indicated as a promising alternative solution for the transportation and storage of natural gas. In the case of accidental release on the ground, a pool fire scenario may occur. Despite the relevance of this accident, due to its likelihood and potential to trigger domino effects, accurate analyses addressing the characterization of pool fires of LNG are still missing.In this work, the fire dynamic simulator (FDS) has been adopted for the evaluation of the effects of the released amount of fuel and its composition (methane, ethane, and propane), on the thermal and chemical properties of small-scale LNG pool fire. More specifically, the heat release rate, the burning rate, the flame height, and thermal radiation, at different initial conditions, have been evaluated for pool having diameter smaller than 10 m. Safety distances have been calculated for all the investigated conditions, as well.Results have also been compared with data and correlations retrieved from the current literature. The equation of Thomas seems to work properly for the definition of the height over diameter ratio of the LNG pool fire for all the mixture and the investigated diameters.The addition of ethane and propane significantly affects the obtained results, especially in terms of radiative thermal radiation peaks, thus indicating the inadequacy of the commonly adopted assumption of pure methane as single, surrogate species for the LNG mixture.     

负压蒸发技术处理废弃钻井液

采用负压蒸发技术处理3种不同组分的废弃钻井液。实验结果表明:最佳蒸发温度为79℃;当蒸发温度低于95℃时,相15~#原液的出水氨氮质量浓度、悬浮物质量浓度、色度分别低于3.40 mg/L、0.093 mg/L、11倍,达到GB 8978—1996《污水综合排放标准》中的一级排放标准;当蒸发温度低于79℃时,钻井液1和钻井液2的出水氨氮质量浓度均低于37.00 mg/L,悬浮物质量浓度均低于0.080 mg/L,色度低于13倍,COD低于114.0 mg/L,达到GB 8978—1996《污水综合排放标准》中的二级排放标准。通过后续过滤除油工艺可降低钻井液中的石油类质量浓度,使最终出水达标排放。