一种火场多参量在线监测系统的设计与实现

火场氧浓度降低、大量烟气遮挡视线和吸入毒性气体是造成火灾中人员无法逃生而窒息死亡的三大主要因素.基于波长调制光谱和谐波探测技术,利用光源调制实现了气体浓度的谐波检测;采用激光烟浓度检测方法,测得减光系数,以表征烟雾浓度.通过合理高效的系统光路和硬件设计,采用分时复用方法,大大缩短了检测周期,每2.5秒便可完成一次对火场多参量的检测,实现了同时对火场中多参量(包括火灾产物中O2、CO、CO2、HCN的浓度和烟雾浓度)的在线实时监测.     

土壤原位覆盖对底泥的修复作用研究

在高度厌氧底泥和富营养化水体构成的模拟生态系统中，采用土壤和硅藻土进行原位覆盖，研究了覆盖技术对水．沉积物界面微环境的改善作用和不同覆盖材料对苦草生长的影响。这2种底质覆盖后，表层底泥氧化还原电位（Eh）分别提高了48．37％和46．77％，底层水体的溶解氧消耗降低，水体中的总氮（TN）和总磷（TP）含量降低；与对照箱体的苦草死亡相比，经过土壤和硅藻土覆盖的箱体中苦草正常萌发、定植和生长；硅藻土箱体苦草的生物量、叶绿素和根茎比均高于土壤覆盖箱体。因此，原位覆盖能有效改善底层水体和表层底泥的氧化还原环境，隔绝污染底泥和延缓营养盐释放，为沉水植物种子萌发和幼苗生长提供有利的生境条件。     

DECLINING INTENSITY OF ACID MINE DRAINAGE IN THE NORTHERN APPALACHIAN BITUMINOUS COAL FIELDS: MAJOR ALLEGHENY RIVER TRIBUTARIES1

ABSTRACT: For more than 30 years, a program of continuous monitoring of pH, acidity, alkalinity, and other parameters has been maintained on a network of large streams degraded by acid mine drainage in the northern Appalachian high sulfur coal region. Continuous records since 1952 are available at a number of stations, and at several stations, acidity records date back to 1930. Comparable analysis techniques were maintained over the period of record, assuring the long term continuity of the database. This monitoring program has captured integrated long term trends within large and complex watersheds with numerous and varied types of mine discharges. The focus of this paper is a historical trend analysis of lightly to severely acid degraded major tributaries of the Allegheny River. Over the past three decades, all of the Allegheny River drainage basin stations have demonstrated steady and substantial declines in acidity and associated increases in pH and alkalinity. The average recorded decline in total acidity at four stations monitored since the 1950s was 94 percent. Since the 1970s, acidity declined by an average of 63 percent at 10 stations. Oxidative exhaustion of pyritic minerals exposed by mining is proposed as a major factor influencing these trends.     

峨眉山降水电导率变化规律初探

本文通过对峨眉山山顶和山下１９８６年～１９９５年降水电导率变化规律的分析发现,其两地电导率与降雨量及降水酸度存在一定的关系,也存在一定的差异。这差异表明山顶降水酸度来源于中长距离的传输     

乌鲁木齐市降水酸度及化学特征的初步研究

降水酸度和离子平衡研究结果表明,乌鲁木齐市降水为非酸性雨,但其PH值有较明显的季节变化,降水中的SO_4~(2-)、Ca~(2+)、和NH_4~+是影响酸度的关键离子,与其他地区相比,乌鲁木齐市降水中的Ca~(2+)浓度是酸雨区(贵阳、重庆)平均值的3.50倍,是非酸雨区(北京、天津)平均值的1.86倍。可见,乌鲁木齐市降水酸度的高低,不仅取决于酸性离子浓度,而且更重要的是取决于碱性离子浓度。     

长江中下游中酸性侵入岩中的黑云母及其地质意义

本区中酸性侵入岩中的黑云母属镁铁系列。有铁叶云母、铁黑云母、铁质黑云母及镁质黑云母四种类型。Ⅰ型长江系列为镁质黑云母;江南系列为铁质黑云母。A型苏州式为铁叶云母和铁黑云母;大龙山式则为镁黑云母—金云母。黑云母的成分与其生成条件有关,在榍石—磁铁矿—石英—角闪石矿物组合中,黑云母含铁度高者(ΣFe/ΣFe+Mg>0.5)其氧逸度随温度上升而增高,形成温度低则压力高,岩体侵位深。含铁度低者(ΣFe/ΣFe十Mg<0.5)氧逸度随温度上升而降低,形成温度高则压力低,岩体侵位浅。各类云母均有自己的成矿专属性。     

酸度介质对原子吸收法测定钙元素灵敏度的影响

对火焰原子吸收法测定钙元素的酸度介质条件进行了分析和论述。通过在不同的盐酸和硝酸介质条件下对钙元素的实际测定,较为充分地论述了不同的盐酸和硝酸介质条件对实验测定的影响,进而选择出最适宜的测定介质条件,提出了相关建议,使方法的测定灵敏度有了显著提高。     

Microscale Spatial Variation in Forest Litter Phytotoxicity

The spatial variation (within a 100 × 100 m plot) in the pollution of forest litter with heavy metals (Cu, Cd, Pb, and Zn), its acidity, and phytotoxicity (measured by the results of the root test using seedlings from a genetically homogeneous sample of common dandelion (Taraxacum officinale s.l.) have been estimated. Forest litter has been sampled in three zones differing in the toxic impact of long-term polymetal pollution by emissions from a copper-smelting plant emissions in the Middle Urals. The phytotoxicity variation is maximum in a moderately polluted plot, where both very high and very low pollution levels were observed, which determines a substantially nonlinear dose–effect relationship. The litter phytotoxicity is mainly accounted for by exchangeable forms of metals. Biological testing of samples from the most polluted plot has demonstrated marked antagonism between heavy metals and acidity.     

石油污染土壤的生物修复技术研究

通过实验室选择性富集培养，从大庆石油污染土壤中获得了能以大庆原油为碳源快速生长的石油降解菌。采用该降解菌对原油污染土壤进行了原位生物联合修复实验。接入降解菌的处理单元分别种植大豆、碱草或加入蓬松剂，与空白试样作对比。各处理单元石油污染土壤中石油烃含量初始值为2228．25mg／kg（以1kg干土计）。经过135d的生物联合修复，石油烃降解率达63．65％-83．26％。     

利用粉煤灰改进含铜酸性废水硫化法处理工艺

用粉煤灰对硫化沉淀法处理含铜酸性废水工艺进行改进试验,试验表明粉煤灰有吸附和絮凝沉降的作用,可显著改善单一硫化法沉降速度慢和脱水困难的缺陷。