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161.
发光细菌法在水质综合毒性在线检测中的应用   总被引:1,自引:0,他引:1  
以海洋发光细菌费氏弧菌(Vibriofischeri)作为检测生物,采用冻干菌粉快速复苏技术,研究费氏弧菌在水质检测中的最佳测试温度和有效性测试条件,并对硫酸锌等多种毒物和几种实际水样进行发光抑制作用分析。研究表明,费氏弧菌冻干粉复苏菌液保存在2~5℃条件下能有效测试7d,最佳测试温度为15℃,最佳测试时间为15min。氯化汞、硫酸锌、硫酸镉等重金属和苯胺、多菌灵、甲醛等有机毒物对费氏弧菌均具有较强的光抑制作用,也即费氏弧菌对以上毒物较为敏感,并能够连续7d保持对同一浓度硫酸锌的敏感性较为一致。对几种实际水样的测试和分析表明,以费氏弧菌为指示生物的发光细菌法能够应用于水质环境安全的综合毒性在线监测预警中。  相似文献   
162.
The effects of various pretreatment methods, including thermo-acid, thermo-alkaline, ultrasonic-alkaline and ultrasonic-acid, on solubilization and subsequent acidification efficiency of waste activated sludge (WAS) were investigated. The results showed that both thermo-alkaline and ultrasonic-alkaline significantly improved the solubilization of WAS at a high concentration (7.4% of total solids). Solubilization of volatile solids (VS) and crude protein was 60.2-61.6% and 66.8-67.5%, respectively. Thermo-alkaline or ultrasonic-alkaline pretreatment also enhanced the efficiency of subsequent WAS acidification. Experimental results showed that they had similar effects on the acidification of WAS. The conversion ratio from VS to total volatile fatty acids (TVFAs) was 0.230 in the case of the ultrasonic-alkaline pretreatment. Through this pretreatment, the level of TVFAs was 68% more than the untreated WAS after 252 h of fermentation. The mechanism of TVFAs production under different pretreatment methods was further investigated and the results indicated that soluble protein was the main substrate for TVFAs production from the WAS after the thermo-alkaline or ultrasonic-alkaline pretreatment.  相似文献   
163.
164.
分析陕西省2000年天气气候变化发现,隆冬降雪明显增多,春旱异常严重,秋霖明显,沙尘暴天气明显增加,这是多年来未曾见到的现象。异常的天气气候使得多种自然灾害并发。  相似文献   
165.
1—硝基芘对斜生栅藻的毒性研究   总被引:2,自引:2,他引:0  
张朝  竺乃恺 《环境化学》1998,17(6):554-557
酿要用评价化学品对藻类毒性的标准实验方法,研究了1-硝基芘对斜生栅藻生长的影响,得到了1-NP抑制斜生栅藻生长的EC50(96h)为0.1824mg.1^-1,实验结果还表明,1-NP对藻生长的抑制作用随时间的延长而增加,抑制物性表现为特久且强度大,抑制机理为不可逆性抑制。  相似文献   
166.
The main purpose of a strategic environmental assessment (SEA) is to facilitate the early consideration of potential environmental impacts in decision-making processes. SEA alternative identification is a core issue within the SEA framework. However, the current methods of SEA alternative formulation and selection are constrained by the limited setting range and lack of scientific evaluation. Thus, the current paper attempts to provide a new methodology based on the extension theory to identify a range of alternatives and screen the best one. Extension planning is applied to formulate a set of alternatives that satisfy the reasonable interests of the stakeholders. Extension priority evaluation is used to assess and optimize the alternatives and present a scientific methodology for the SEA alternative study. Thereafter, the urban traffic plan of Dalian City is used as an example to demonstrate the feasibility of the new method. The traffic planning scheme and the environmental protection scheme are organically combined based on the extension theory, and the reliability and practicality of this approach are examined.  相似文献   
167.
渤海排污口邻近海域异养细菌的组成与分布   总被引:1,自引:0,他引:1  
对渤海4个重点监测排污口(北塘、大蒲河、弥河和虞河)邻近海域异养细菌的组成和分布进行了调查研究。结果表明,分离到的各排污口邻近海域的细菌隶属于变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)、放线菌门(Acti-nobacteria)和拟杆菌门(Bacteroidetes)4个细菌类群,其中变形菌门的细菌最丰富。各排污口的优势菌有所不同,北塘、弥河2个采样点的优势菌分别为Bacillus sp.、Pseudoalteromonas sp.,大蒲河采样点的优势菌为Vibrio sp.和Oceanospirillum sp.,虞河采样点的优势菌为 Shewanella sp.和 Bacillus sp.。多维尺度分析表明,北塘和虞河采样点的细菌种群特征较相近,细菌种群分布特征可能与排污口的海洋环境有一定的相关性。  相似文献   
168.
Presented here is a study of the geochemical dynamics of the entire River Sava watershed, a major tributary of the River Danube which has not previously been investigated. The sampling was performed at 33 selected locations along the main channel of the stream and at its largest tributaries during three sampling seasons (fall 2005, spring 2006 and fall 2006), going from headwater locations to the mouth near the confluence with the Danube. Almost 80% of the solutes are derived from carbonate mineral weathering and represent over 50% of specific HCO(3)(-) flux normalized to unit basin area at the mouth of the Danube. Statistical analysis indicates that agricultural and industrial sources contribute significantly to increased Na(+), K(+), Cl(-), SO(4)(2-) and NO(3)(-) concentrations in tributary waters. Different processes control the water chemistry along the course of the Sava's drainage-the upper reaches are largely regulated by contributions from carbonate mineral weathering, the middle reaches are influenced by agricultural activity and biological processes related to eutrophication, while the lower reaches tend to have more pronounced parameters related to the industrial processing along with leakages from municipal sanitary systems of these higher population density areas.  相似文献   
169.
阐述了地级市空气自动监测多参数站(超级站)建设的必要性,提出了统筹考虑、分期实施与突出重点、兼顾一般的建设思路,介绍了站房选址原则。指出超级站建设应以常规监测、霾监测、光化学烟雾监测、空间立体监测和源解析监测为目标,实施质量控制和质量保证手段,设置数据采集和显示平台,满足对大气复合污染的监测需求。  相似文献   
170.
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