pH对生物滤池处理含H_2S和NH_3混合恶臭气体的影响

研究了pH对生物滤池处理含H2S和NH3混合恶臭气体的影响,以及不同pH下的物质转化情况和去除机制。结果表明,不同pH下,生物滤池对H2S和NH3的去除率是不同的。在强酸性(pH为2左右)和中性(pH为7左右)条件下,H2S均有较好的去除效果,这分别归于嗜酸性硫细菌和非嗜酸性硫细菌的生物降解作用。低pH下,NH3的去除归于化学中和作用;中性(pH为7左右)条件下,NH3有较高的去除率,主要依靠生物硝化作用。通过考察pH对生物滤池处理效果的影响,确定了生物滤池处理含H2S和NH3混合恶臭气体的pH控制条件和去除机制,为恶臭气体生物处理工艺的选择提供依据。     

从拒绝《京都议定书》看美国政府环境外交意图

作为国际社会最具影响力的环境协约,《京都议定书》却被美国政府拒之门外,通过对美国近年来针对该协约的态度及对全球变暖问题的外交举措分析,可以看出,美国政府环境外交行为的意图主要体现在三个方面,即规避不利条款的束缚;设计和实施替代性方案;积极争取国际环境领域的领导地位。     

Evaluation of potential genotoxicity of five food dyes using the somatic mutation and recombination test

In this study, different concentrations of five food dyes (amaranth, patent blue, carminic acid, indigotine and erythrosine) have been evaluated for genotoxicity in the Somatic Mutation and Recombination Test (SMART) of Drosophila melanogaster. Standard cross was used in the experiment. Larvae including two linked recessive wing hair mutations were chronically fed at different concentrations of the test compounds in standard Drosophila Instant Medium. Feeding ended with pupation of the surviving larvae. Wings of the emerging adult flies were scored for the presence of spots of mutant cells which can result from either somatic mutation or somatic recombination. For the evaluation of genotoxic effects, the frequencies of spots per wing in the treated series were compared to the control group, which was distilled water. The present study shows that carminic acid and indigotine demonstrated negative results while erythrosine demonstrated inconclusive results. In addition 25 mg mL⁻¹ concentration of patent blue and 12.5, 25 and 50 mg mL⁻¹ concentrations of amaranth demonstrated positive results in the SMART.     

鄱阳湖老爷庙水域细菌群落组成分析

通过提取鄱阳湖老爷庙水域水体细菌总DNA, 构建细菌16SrRNA基因文库和序列测定等手段,以期揭示鄱阳湖老爷庙水域的细菌群落组成并探讨细菌多样性与湖泊水体理化参数之间的关系。研究结果认为：来自老爷庙水域的2006年10月（PN06 10）和2007年5月 (PN07 5) 的细菌文库中的180个阳性克隆产生了66个细菌分类操作单位（OTUs）,这些细菌主要分属于：变形菌Alpha 纲,Beta 纲,Gamma 纲,Epsilon 纲,拟杆菌门,放线菌门,浮霉菌门,酸杆菌门和OP10等9大类型。2006年10月老爷庙水域的优势菌群为Beta 变形菌;2007年5月优势菌群为Gamma 变形菌和拟杆菌,表明鄱阳湖细菌组成在不同的季节显著不同。进一步系统发育分析表明：大部分细菌的最相似序列来源于淡水,湖泊和土壤的未培养细菌,且部分细菌与环境污染物降解有关     

Wild fire impact on copper, zinc, lead and cadmium distribution in soil and relation with abundance in selected plants of Lamiaceae family from Vidlic Mountain (Serbia)

Fire has been considered as an improving factor in soil quality, but only if it is controlled. Severe wild fire occurred in the summer 2007 on the Vidlic Mountain (Serbia) overspreading a huge area of meadows and forests.Main soil characteristics and content of heavy metals (Cu, Pb, Cd, Zn) in different fractions obtained after sequential extraction of soil from post-fire areas and from fire non disturbed areas were studied. In four plant species of Lamiaceae family (Ajuga genevensis L., Lamium galeobdolon (L.) L., Teucrium chamaedrys L., Acinos alpinus (L.) Moench.), that grow in typical habitats of the mountain, distribution of heavy metals in aerial parts and roots was investigated too.For all samples from post-fire area cation exchange capacity and soil organic matter content are increased while rH is decreased. Fire caused slightly increased bioavailability of the observed metals but more significant rise happened in metal amounts bound to oxides and organics. The plants showed variable behavior. T. chamaedrys collected on the post-fire area contained elevated concentrations of all analyzed metals. A. alpinus showed higher phytoaccumulation for Zn and Cd, while the other two plant species for Pb and Cd in the post-fire areas.     

整体式催化剂选择性催化氧化硫化氢

在堇青石蜂窝陶瓷基体上分两步涂覆了SiO₂和TiO₂两种涂层,再通过浸渍法制备了V₂O₅/TiO₂-SiO₂/堇青石整体式催化剂。采用BET、XRD、XRF、SEM和H₂-TPR等方法对催化剂进行了表征,并对催化剂的H₂S选择性催化氧化活性进行了评价。结果表明：V₂O₅负载量为20%（w）时,催化剂的活性最好;在反应温度180 ℃、空速3 000 h^-1、V（O₂）∶V（H₂S）=0.5的条件下,转化率达96.94%,硫产率达95.41%。在40 h的稳定性试验过程中,转化率稳定在96%左右,硫产率稳定在94%左右,催化剂的稳定性较好。与传统颗粒状催化剂相比,该整体式催化剂更具工业应用前景。     

Bisphenol A and Bisphenol S release in milk under household conditions from baby bottles marketed in Italy

A simple and sensitive validated analytical method based on liquid chromatography coupled to tandem fluorescence (FD) and ultraviolet (UV) spectrophotometry was applied to monitor the presence of bisphenol A and bisphenol S in plastic baby bottles marketed in Italy. The limits of detection (LOD) were 3.75 ng mL^?1 and 80.00 ng mL^?1, and those of quantification (LOQ) were 12.51 ng mL^?1 and 260.00 ng mL^?1 for BPA (FD detection) and for BPS (UV detection), respectively. BPA was found in only four samples, two samples undergone to microwave heating and two samples undergone to bottle warmer heating either at 40°C or at 80°C. Although the quantities of leached BPA were well below the reference dose for daily intake established by the European Food Safety Authority (EFSA) (4.0 µg kg^?1 bw/day), the release of BPA and BPS from these plastic materials should be carefully considered by the government authorities to increase people's awareness on this issue and to protect the most vulnerable population group.     

海湾安防(GST)消防系统在高校图书馆的应用

从火灾探测器、报警装置、联动系统等方面介绍现代消防系统的构成、工作原理、运行情况。构建科学合理的消防系统,有助于实现高校图书馆火灾的早期探测、智能化控制,防灾于未然,将消防安全隐患消灭于萌芽状态。介绍海湾安防(GST)有限公司的情况,及其产品在中北大学图书馆的实际应用情况及存在问题,对消防系统在图书馆的应用提出思考和建议,以供图书馆、资料室、书库、档案馆等单位借鉴和参考。实践表明:GST有限公司生产的消防产品能满足图书馆的消防需求,同时还应加强图书馆工作人员的消防意识和消防管理。     

海洋平台密集作业空间内H_2S扩散分析

针对含硫油气田开发生产中,硫化氢(H_2S)在振动筛房等密集作业空间内泄漏扩散造成的潜在人员毒害问题,从确定H_2S扩散规律、建立事故控制措施的角度展开分析.根据海洋平台空间环境特点,采取计算流体动力学(CFD)建立用于分析H_2S扩散过程的理论模型和数值模拟方案.就某海洋平台振动筛房在舱门关闭、打开和房内安装换气机3种条件下的H_2S扩散过程进行分析,确定H_2S浓度变化和分布规律.通过对比不同舱室条件下的H_2S影响程度,推荐在平台生产过程中封闭可能出现H_2S泄漏的舱室并安装换气机.进一步分析了换气机的工作效率,建立了简化数学模型以快速预测换气机工作时间,并与CFD结果进行了验证.     

基于S3C2410嵌入式视频监控系统的研究

视频监控系统是一门集计算机技术、通信技术和数字视频技术于一体的综合系统.它以其直观、方便、信息内容丰富等特性而被广泛应用于工业生产、交通、电力、银行、智能办公大楼等场所.本文阐述了基于S3C2410嵌入式视频监控系统的硬件设计和软件开发.硬件部分包括USB摄像头视频图像采集处理模块、GPRS无线数据传输模块等.软件模块主要包括嵌入式视频采集、视频图像的编解码等.