战斗机飞行员加压供氧面罩高空供氧防护性能评定

详细介绍了战斗机飞行员新型YM9915加压供氧面罩和TK - 11飞行保护头盔配套的高空供氧防护性能生理评价实验结果。分析讨论了新型加压供氧面罩与飞行保护头盔配套的供氧防护性能特点 ,并针对其不足提出改进建议     

厨余垃圾堆肥蓬松剂技术研究

为解决厨余垃圾好氧堆肥过程中含水率高、有机物含量大等问题，分别添加锯末、树叶、秸杆和干马粪为蓬松剂进行厨余堆肥技术研究。采用翻转式堆肥设备，利用出口气体检测仪、温度计及扫描电镜，研究添加蓬松剂堆肥过程中耗氧速率，温度，出口CO2、H2S、O2浓度，堆料结构及微生物群落变化。试验结果表明，添加蓬松剂堆肥，堆料所能达到的高温及其停留时间、好氧速率、产CO2气体能力均明显优于对照组，并能很好地控制出口H2S气体浓度。特别是以干马粪和锯末作为蓬松剂，可明显改善堆料孔隙率，吸收多余水分，加速氧和有机物的传输速率，改善好氧堆肥微环境。因此，厨余垃圾堆肥过程中加入干马粪、锯末等蓬松剂是保证堆肥顺利进行、提高堆肥效率的有效方法。     

污水中化学需氧量速测法条件优化与实践

介绍了速测法测定污水中COD的方法。通过对该方法使用参数的优化选择,对优化前后结果进行了多次验证;对经典的重铬酸钾氧化滴定法与速测法进行了方法比对实验和对比实验,取得良好的效果,提高了准确度。     

高海拔矿山掘进工作面局部供氧装置研究*

为缓解高海拔矿山掘进作业面低氧问题,将供氧管与环形空气幕相结合,空气幕在作业人员四周形成空气屏障,设计1种用于高海拔矿山掘进工作面的新型供氧装置。以中国云南某海拔3 400 m的铜矿为例,运用ANSYS Fluent软件建立掘进工作面空间模型,根据矿山实际情况确定边界条件,对比研究单一供氧管模式和新型供氧装置的富氧效果差异,并分析空气幕出风口形式、风量对富氧效果的影响。研究结果表明:新型供氧装置的富氧效果优于单一供氧管模式;环状缝隙出风口优于圆孔出风口,并且当环状缝隙宽度为0.010 m、风量为0.014 m3/s时,呼吸带平均氧气质量分数为27.59%,达到最佳富氧效果。新型供氧装置能有效提高作业人员周围呼吸带区域的氧气质量分数。     

软质聚氨酯泡沫阴燃前期热解特性研究

采用DSC-TGA(差示扫描量热-热重分析)同步热分析仪对软质聚氨酯泡沫(聚氨酯软泡)在不同氧气体积分数(0、10％、30％、50％)和不同加热速率(10 K/min、20 K/min、50 K/min)下热解到800℃的过程及其对阴燃的影响进行了研究.结果表明,当氧气体积分数介于10％ ～ 50％时,聚氨酯软泡热失重DTG曲线只有1个峰;当氧气体积分数降低到10％时,DTG曲线开始逐渐分离为2个峰;当氧气体积分数降为0(即氮气气氛)时,DTG曲线已经明显分为2个峰.这表明氧气体积分数对聚氨酯软泡热解特性具有重要作用.氧气体积分数和加热速率降低均对聚氨酯软泡的热解有抑制作用,均能减小阴燃传播速率和向明火转化的可能性.加热速率降低主要是延长了聚氨酯软泡的热解周期,从而减小了热解可燃气体积分数和放热速率.氧气体积分数降低对聚氨酯软泡热解的影响相对复杂的多:当氧气体积分数从10％降低到0时,主要提高了聚氨酯软泡的分解温度,而对热解速率影响不大;当氧气体积分数介于10％～50％时,氧气体积分数减小主要会降低聚氨酯软泡的热解速率、放热速率和放热量而对热解温度影响相对不大.氧气体积分数和加热速率降低抑制了多元醇的分解,而多元醇是聚氨酯软泡维持阴燃或向明火转化的主要物质及能量来源.     

医用高压氧舱的技术改造

介绍了医用高压氧舱的现状，针对使用过程中存在的事故隐患，提出了相应的改进措施和修理改造方案。     

A Tool for Modeling the Winter Oxygen Depletion Rate in Arctic Lakes1

Abstract: Many arctic lakes freeze completely in winter. The few that retain unfrozen water for the entire winter period serve as overwintering fish habitat. In addition to serving as fish habitat, water in arctic lakes is needed for industrial and domestic use. Permits for water extraction seek to maximize water use without impacting dissolved oxygen (DO) levels and endangering fish habitat. The relationship between lake volume, winter DO budget, and extraction of water through pumping has historically not been well understood. A management model that could estimate end‐of‐winter DO would improve our understanding of the potential impacts of different management strategies. Using under‐ice DO measurements (November to April) taken from two natural lakes and one flooded gravel mine on the North Slope of Alaska, a physically based model was developed to predict end‐of‐winter DO concentration, water‐column DO profiles, and winter oxygen depletion rate in arctic lakes during periods of ice cover. Comparisons between the measured and model‐predicted oxygen profiles in the three study lakes suggest that the depth‐based DO modeling tool presented herein can be used to adequately predict the amount of DO available in arctic lakes throughout winter.     

人工湿地脱氮途径及其影响因素分析

简述了人工湿地脱氮模型。各种形态的氮在人工湿地系统中可以通过氨的挥发、植物吸收、介质沉淀吸附以及微生物硝化/反硝化作用等过程被去除。讨论了各脱氮途径对人工湿地脱氮的贡献,在大多数人工湿地的pH条件下,湿地地面氨挥发可以忽略,湿地植物叶片氨挥发量尚不清楚。湿地介质的直接吸附是短期的。植物在湿地脱氮过程中起了重要作用,但一般认为植物直接吸收和存储只占湿地脱氮的一小部分,一般低于30%。微生物的硝化/反硝化作用,是人工湿地脱氮的最主要的形式。讨论了影响人工湿地硝化作用的主要因素:溶解氧,pH和温度。大多数人工湿地的pH适合硝化作用,溶解氧和温度对湿地硝化作用的影响最大。温度不仅影响微生物的硝化作用,而且可以间接地影响植物的生长从而影响人工湿地的脱氮性能。     

微生物菌剂对不同废水的适配试验

采用15种不同的微生物菌剂,以葡萄糖配水、中药提取废水、啤酒废水、氨氮配水等为基质,分别测定了微生物菌剂的耗氧速率和厌氧比产甲烷速率,以单位菌剂对不同基质的耗氧速率和厌氧比产甲烷活性为指标,比较了各菌剂对废水的适配性.根据测定结果选择活性高的菌剂,在试验室进行了菌剂对废水的连续处理试验.结果表明,不同菌剂对同一种废水的好氧或厌氧活性不同,同种菌剂对不同废水的好氧和厌氧活性不同.废水的连续处理试验取得良好的处理效果.No.8菌剂处理葡萄糖配水,系统有机负荷最高可达(COD)10.8 g L-1d-1,COD去除率可达90%以上;采用No.10菌剂处理氨氮配水,好氧氨氮负荷可达(NH4-N )1.42 g L-1d-1,厌氧氨氮负荷可达(NH4-N )0.3 gL-1d-1,系统NH4-N 去除率可达90%以上.图2表3参8     

Ventilation or nest defense—parental care trade-offs in a fish with male care

Brood guarding animals face many critical trade-offs. Sand goby males (Pomatoschistus minutus) build nests with larger openings during low oxygen conditions, presumably to enhance ventilation. However, this may make the nest easier for egg predators to detect and harder for guarding males to defend. Manipulating oxygen level and predator presence (a small crab) for small and large males, we found support for a parental trade-off between fanning and nest defense. An increased fanning activity resulted in less time for guarding. Small males and males in low oxygen showed a higher fanning expenditure than large males and males in high oxygen, but surprisingly, filial cannibalism did not differ between these groups. Males built larger nest openings in low than high oxygen. However, males in both high and low oxygen treatments reduced their nest opening size in the presence of a predator, again indicating an important trade-off between ventilation and nest defense.