硫酸锰废渣浸出液对斑马鱼的毒性及抗氧化酶活性的影响

已有研究表明,堆积在湘西花垣河河岸的硫酸锰废渣含有多种重金属,可能是导致花垣河河水和沉积物重金属污染的主要原因.为了评价硫酸锰废渣的潜在生态风险和对水生动物的毒性,本研究分析了硫酸锰废渣浸出液中的主要重金属成分,用漫出液对斑马鱼进行了急性毒性实验,观察在急性胁迫下斑马鱼的体征变化,测定了斑马鱼在亚致死浓度下的生化指标的...     

Aerosol size distributions in urban Jinan: Seasonal characteristics and variations between weekdays and weekends in a heavily polluted atmosphere

Aerosol size distributions, trace gas, and PM(2.5) concentrations have been measured in urban Jinan, China, over 6 months in 2007 and 2008, covering spring, summer, fall, and winter time periods. Number concentrations of particles (10-2,500 nm) were 16,200, 13,900, 11,200, and 21,600 cm(?-3) in spring, summer, fall, and winter, respectively. Compared with other urban studies, Jinan has higher number concentrations of accumulation-mode particles (100-500 nm) and particles (10-2,500 nm), but lower concentrations of ultrafine particles (10-100 nm). The number, surface and volume concentrations, and size distributions of particles showed obvious seasonal variation and are also influenced by traffic emissions. Through correlation analysis, traffic emissions are proposed to be a more important contributor to Atkien-mode and accumulation-mode particles than coal firing. Around midday, the presence of nanoparticles and new particle formation is limited to pre-existing particles from traffic emissions and the mass transport of particles from suburban and rural areas. Compared with other studies in urban areas of Europe and the USA, the variation of particle number concentration and related gas concentration in Jinan between weekdays and weekends is smaller and the reasons has been deduced.     

Characteristics of CO2 release from forest soil in the mountains near Beijing

CO₂ release from forest soil is a key driver of carbon cycling between the soil and atmosphere ecosystem. The rate of CO₂ released from soil was measured in three forest stands (in the mountainous region near Beijing, China) by the alkaline absorption method from 2004 to 2006. The rate of CO₂ released did not differ among the three stands. The CO₂ release rate ranged from ??341 to 1,193 mg m^???2 h^???1, and the mean value over all three forests and sampling times was 286 mg m^???2 h^???1. CO₂ release was positively correlated with soil water content and the soil temperature. Diurnally, CO₂ release was higher in the day than at night. Seasonally, CO₂ release was highest in early autumn and lowest in winter; in winter, negative values of CO₂ release suggested that CO₂ was absorbed by soil.     

原油输送站清罐作业闪爆事故技术分析

1事故概况2010年6月29日16时40分左右,辽阳某公司原油输送站1个30000m3原油罐在清罐作业过程中,发生可燃气体闪爆事故,致使罐内作业人员3人死亡,7人受伤。2010年6月,该公司原油输送站对1个30000m3原油罐进行清罐作业,该罐顶部设有3个通风口,下部设有2个人孔、1个排渣口。25日上午9时厂方采用0.3MPa压力的蒸汽进行蒸罐,持续时间77h,28日下午2点停止供应蒸汽,然后打开各罐孔进行自然冷却。     

外军皮肤防护器材化学防护性能测试与评价用标准物质研究进展

本文简迷了皮肤防护器材--化学防护服(衣)化学防护性能试验与评价用标准物质的重要性,系统地概述了外军化学防护服(衣)化学防护性能试验与评价用标准物质的研究现状,并提出了我国化学防护服(衣)防护性能试验与评价用标准物质研制过程中应注意的一些问题.     

Matrix-bound phosphine and phosphorus fractions in paddy soils

Phosphine (PH(3)) is a natural gaseous carrier of phosphorus (P) in its geochemical cycles, and it might be important to the P balance of natural ecosystems. Paddy fields are thought to be one of the main sources responsible for the production and emission of PH(3) in to the environment. The relationships between matrix-bound PH(3) (MBP) and different P fractions, as well as selected metals were investigated to explore the possible production of MBP and its link to P cycle in the paddy soils. MBP range from 20.8 (-1) to 502 ng kg(-1) with an average of 145 ng kg(-1). Concentrations at the milk stage are significantly higher than at the jointing stage. The total P range from 333 mg kg(-1) to 592 mg kg(-1). Average P fractions decrease in the order: Ca-P (69.9%) > Organic P (16.5%) > occluded P (6.50%) > Fe-P (5.93%) > dissolved P (0.80%) > exchangeable P (0.32%) > Al-P (0.02%). Different levels of nitrogen fertilizer have little effect on the contents of MBP, P fractions and metals. A significant positive correlation between MBP and Ca-P (p = 0.002), as well as between MBP and Ca (p = 0.008) could be observed, suggesting that Ca-P mainly affects the production of MBP in the paddy soils. It is suggested that soil MBP is strongly linked to Ca-P fertilizer use because soil spiked with P-fertilizer produced an additional 758 ± 142 ng of MBP per kg of soil, compared to only 81.7 ± 12.3 ng of MBP per kg of unspiked soil. No correlations are found between MBP and other P fractions, or between MBP and Al, Fe and Mn.     

物联网技术在地震救灾中的应用

研究了物联网技术在地震救灾中的应用。在体系结构设计中主要针对无线传感器网络节点、自组网技术、数据采集与灾情分析软件、多源信息融合等几个方面开展研究,构造出基于物联网技术的信息处理平台,在此基础上组建一个地震监测、预警及救灾部署控制中心,并实现信息处理平台与城市基础设施的互连接口。最终,在地震救灾中能够利用多源信息融合技术为控制中心实现决策和指挥提供科学、高效的服务。     

龙羊峡水库地震溃坝的可能性及溃坝洪灾程度的分析

讨论了龙羊峡库区将来发生大地震的可能性;分析了万一产生溃坝的灾害链问题。计算了其溃坝后洪水到达下游贵德县、康扬镇、尖扎县、循化县和兰州市的洪水最大流量、洪水起涨时间和消退时间。     

汶川地震地表变形特征

汶川地震地表变形特征丰富多彩。在震后40天自北至南对地震地表变形现象进行了为期10天的专题考察和分析,对北川、擂鼓、汉旺、蓥华、白鹿、小鱼洞、虹口和映秀等8个断裂出露部位进行了重点剖析。结果表明,不同侧面,不同级次的现象均显示出统一的变形变位图案,但具体而言它们比理论模型、规例要复杂得多。它们具体表现为:沿汶川地震断裂面推挤形成隆起,产生纵向、横向裂隙;推挤前缘冲断塌落,形成逆断型崩积楔;多方向挤压、或引张,显示同一应力作用下变形组合的复杂性。这些均不同程度地丰富了现有的应力作用理论。     

Pollution characteristics and health risk assessment of polycyclic aromatic hydrocarbons and nitrated polycyclic aromatic hydrocarbons during heating season in Beijing

Polycyclic aromatic hydrocarbons(PAHs) and their nitrated derivatives(NPAHs) attract continuous attention due to their outstanding carcinogenicity and mutagenicity. In order to investigate the diurnal variations, sources, formation mechanism, and health risk assessment of them in heating season, particulate matter(PM) were collected in Beijing urban area from December 26, 2017 to January 17, 2018. PAHs and NPAHs in PM were quantitatively analyzed via gas chromatography-mass spectrometry(GC-MS). ...