Environmental health in minority and other underserved populations: Benign methods for identifying lead hazards at day care centres of New Orleans

This study tests the hypothesis that exterior sources of lead dust are more important than interior sources in the route of exposure of children. Benign field methods were used to distinguish between potential and actual lead exposure problems. Utilising hand wipe and surface wipe techniques, hand and environmental samples were obtained from selected day care centres at different locations within New Orleans. Previous research has shown that soil lead is determined by location within the city. Private and public day care centres were selected from inner and outer city areas to estimate the extent of hand lead exposure. To measure and identify the extent of environmental lead exposure, hand wipes were taken before and after playing outdoors. Results of preliminary findings show that outdoor lead dust is a more potent contaminant of hands than indoor lead dust. An association was found between the amount of lead on children's hands after playing outdoors and the lead content in the exterior dust and soil. Although two girls out of forty children had exceptionally high hand lead quantities after playing outdoors, in general, boys have higher hand lead levels than girls. The private inner-city day care centre had a severe contamination problem in its outdoor play area. By contrast, the outdoor play area of the public inner city day care centre is of such a high quality that the quantity of lead dust is independent of location in the city.     

惠州绿化乔木叶片及其叶面降尘对大气SO2污染的生物监测

采用常规采样及碱片挂片法同步监测广东省惠州市大气SO2体积分数,用ICP-AES测定了惠州市不同功能区的2种主要绿化树种大叶榕(Ficus virens Ait var.sublanceolata(Miq.) Corner)、紫荆(Bauhinia blakeana)叶片及其叶面降尘的硫质量分数。结果表明,不同功能区植物叶片和降尘的硫质量分数差异显著,其综合污染指数(PI)以商业交通区、工业区、居住区、清洁区的趋势递减。叶片中硫的质量分数随春、夏、秋季而增长,季节差异显著。植物叶片、降尘中硫质量分数随交通流量的减少而降低。叶片和叶面降尘中硫的质量分数与大气硫酸盐化速率三者显著相关,大叶榕和紫荆与降尘协同生物监测大气SO2的二元数学模型的相关系数分别为R=0.995和R=0.990,明显优于植物与硫酸盐化速率监测SO2的常规一元数学模型。表明大叶榕、紫荆叶片及其叶面降尘均可作为城市区域大气SO2污染的有效指示剂,叶片的长期效益和季节效益显著,降尘则短期效益显著;两者协同监测,可靠性和灵敏度更高,应用前景广阔,可为地方和区域环境监测和评价提供参考。     

A very simple yet accurate solution to the thermal explosion problem

A very simple solution to the thermal explosion problem for one-dimensional solids is presented. The solution produces analytical expressions for the criticality condition. Two different solutions are used. One solution gives higher answers than those known from exact solutions and the second solution gives lower answers. This allows bracketing the expected answer with a determined tolerance. The results obtained compare quite favorably with those obtained from known exact numerical solutions. This allows the utilization of the present method for many a practical problem with an acceptable tolerances.     

煤层注水降低综采工作面煤尘浓度的研究

在深入研究官地矿９＃ 煤渗透特性的基础上,提出动压预注水的煤层注水方案与参数,并在官地矿进行了工业性试验,取得了降低综采工作面煤尘浓度６０％ 以上的明显效果。它对我国煤矿有效实施煤层注水、降低工作面粉尘浓度具有实际指导意义     

Z198型除尘器在生石灰硝化工程上的应用

对Z198型布袋除尘器的结构、工作原理等作了介绍,并分析了其在生石灰硝化工程中的应用情况及效果,同时指出了在使用过程中存在的问题。     

化学纤维栅湿式过滤除尘的实验研究

化学纤维栅湿式除尘是一种复合机理的新型湿式过滤除尘技术,其过滤风速为2～10m/s,阻力仅为200～500Pa,除尘效率达到99.62％,能很好解决矿山溜井卸矿产生的粉尘,使溜井含尘气流经净化后达到新鲜风流卫生标准。     

冲天炉烟气除尘

采用湿法除尘,在烟气管道内设置喷嘴,使烟气充分加湿和降温后再进入立式文丘里,旋流析除尘器,消除了ＣＯ爆炸危险,在冲天炉上部烟囟顶端设安全２盖板,以保证生产的正常进行;烟气经湿式除尘后达到排放标准。     

锅炉烟尘排放浓度超标成因分析及控制对策

分析了锅炉燃烧排出的危害人类健康的污染物烟尘及ＳＯ２超标的成因,以及长庆油田燃煤锅炉烟道气的监测结果。提出了控制锅炉烟尘排放浓度的对策及消烟措施。例如：推行煤炭洗选,改进燃料结构,限制烟尘超标的锅炉产品制造、安装,改进燃烧方式,强化炉内燃烧,改造除尘器。     

昆明市烟尘控制区建设过程中存在的问题分析

针对昆明市世博、新迎片烟尘控制区环境监测中存在的问题,提出了解决方法加强环保宣传,提高环境意识;加强人员素质培养,提高管理水平;加强除尘脱硫技术的研究和推广,从源头抓起,减少污染等,这样,才能管理好烟尘控制区,真正达到烟尘控制的目的.     

热喷处理污泥及其复混肥的养分效率与生物效应

采用室内分析和田间生物试验，研究了热喷处理污泥及其复混肥的养分供应能力及它们在农地上施用对土壤肥力、青菜产量及其品质的影响。结果表明：热喷处理能有效杀灭污泥中病原物，除自，并可使污泥中水溶性有机碳和速效氮含量分别提高87％，19％和35％，施用热喷污泥制成的复混肥不但比等养分的无机复合肥多增产38％，而且青菜体内Vc和水溶性总糖等营养品质也有明显的提高，NO3^-却只有无机复合肥处理的一半左右，污泥经势喷处理有利于提高污泥中养分的生物有效性，特别是热喷污泥制成的复混肥氮磷养分利用率显著高于无机复合肥，施用污泥和污泥复混肥还能提高土壤肥力，比单纯大量施用污泥要安全得多，土地使用年限可延长40倍。