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121.
千岛湖是较为典型的大型深水湖泊,近年来水环境质量在湖体上存在差异.认识这种差异并根据差异的程度,对湖泊进行区划,并因地制宜制定千岛湖水域的环境保护措施,制定湖泊水环境保护的方向性和战略性目标,具有重要的现实意义.文章从生态林业、生态工业、生态农业和生态旅游业等领域,提出了千岛湖生态环境保护的对策,以期为国内其它湖泊提供环境保护的借鉴.  相似文献   
122.
A challenge for statewide stream monitoring is visualizing the spatial and statistical characteristics of such data to compare the biotic condition of watersheds and relate that condition to watershed‐level estimates of instream variables. We used linked micromaps on stream survey data of 25 subbasins (766‐5,982 km2) for biotic condition, nine water quality, and two habitat variables. Subbasin biotic condition was negatively correlated with conductivity, magnesium and sulfate concentrations, and weakly positively correlated with habitat scores of sedimentation and embeddedness, with higher scores indicating better habitat. Positive spatial autocorrelation was detected among the subbasins in both habitat variables, iron concentration, pH, and exceedances of fecal coliform criteria as shown in linked micromaps. A spatial principal components analysis reduced the 11 environmental variables to two principal axes. The first axis synthesized a gradient of water quality and habitat scores among the subbasins. Subbasin biotic condition regressed on first axis subbasin scores had a significant, negative slope and accounted for 55% of the variation. Subbasins in degraded biotic condition had elevated conductivities and ion concentrations in northern and southern subbasins, and low habitat scores in western subbasins. Through linked micromaps, we compared the biotic condition among subbasins and identified stressors prevalent among subbasins that affected biotic condition.  相似文献   
123.
The disposal of sewage sludge (SS) and reed straw (RS) has becoming a critical issue due to their rapid production. In this study, the SS-based activated carbon (SSC) was produced by introducing the RS as a component material. Properties including BET surface area, pore volume, surface chemical groups, and morphologies were characterized. The adsorption of 1-diazo-2-naphthol-4-sulfonic acid (1,2,4-Acid) and 2-Naphthol (2-Nap), which differs in their physicochemical properties, on as-prepared carbons were investigated. The overall adsorption was found to be jointly controlled by external mass transfer and intraparticle diffusion, and the optimal pH was found to be 5 due to their electrostatic attraction. Further study revealed that the SS- and RS-based carbons (SC and RSC, respectively) exhibited different adsorption behavior toward 1,2,4-Acid and 2-Nap. The calculated adsorption capacity from Langmuir–Freundlich model of SC and RSC for the two intermediates was 141.0, 84.6 mg g-1 and 48.2, 110.2 mg g-1, respectively, whereas their hybrid product (SSC) showed comparable capacity for 1,2,4-Acid (117.8 mg g-1), as well as higher capacity for 2-Nap (157.5 mg g-1). It was found that the presence of meso- or macropores facilitates the precipitation of mineral phases of inorganic substances during carbonization, attracting the molecules with polar functional groups, while the introduction of C-rich RS to SS enhances the adsorption of hydrophobic molecules.  相似文献   
124.
石油与石油化工企业液体石油产品储运过程中液体石油产品带有静电,带有静电的液体石油产品进入容器内(如油罐)后,液体石油产品的液面会产生较高静电电位,此时进行液体石油产品的采样、测温、检尺等作业时,易发生静电放电,从而造成着火爆炸事故。20世纪六七十年代,是油品采样静电闪爆事故的高峰期,国内一些炼油厂采样、检尺、测温等静电闪爆事故人们至今记忆犹新。  相似文献   
125.
浙江某水库大坝渗流安全综合分析   总被引:1,自引:0,他引:1  
娄一青  丁丽  何鲜峰 《灾害学》2008,23(1):32-36
对浙江省某水库大坝的测压管观测资料进行了分析,建立了用来预报测点水位并能反映大坝实际渗流性态的统计模型。在此基础上结合观测资料采用有限元方法反演了坝体、坝基各分区的渗透系数,预测未来高水位时大坝的渗流性态,并建立了物理概念明确、预报效果较好的渗压确定性模型。  相似文献   
126.
曝气生物流化池生物强化处理高氨氮制革废水研究   总被引:3,自引:0,他引:3  
以曝气生物流化池(ABFT)I艺为核心,通过投加高效菌酶添加剂(简称菌荆)的方法对高氨氮制革废水进行生物强化处理研究.结果表明,在菌剂投加量为0.4 kg/m3,总水力停留时间为32 h(其中生化处理段水力停留时间为29 h)条件下,菌剂投加10 d后氨氮的去除率可达80.2%,25 d后系统即可稳定运行;出水氨氮平均为4.8 mg/L,去除率为98.8%;出水COD平均为137 mg/L,去除率为76.4%.无机碳化合物和生长因子对硝化反应有促进作用,使氨氮的去除率提高约6.6%.该结果显示了ABFT工艺在处理高氨氮制革废水上具有明显优势.  相似文献   
127.
Transition-metal is known to catalyze peroxymonosulfate (PMS) decomposition to produce sulfate radicals. Here we report reactions between PMS and chloride, without a need of transition metals, also can be used to degrade organic dye pollutant (Rhodamine B, (RhB)). Some important operating parameters, such as dosages of PMS and Cl?, pH of solution, temperature, ionic strength, and several common cations, were systematically investigated. Almost complete decoloration of RhB was achieved within 5 min ([PMS]?=?0.5 mM, [Cl?]?=?120 mM, and pH 3.0), and RhB bleaching rate increased with the increased dosages of both PMS and chloride ion, following the pseudo-first-order kinetic model. However, the total organic carbon (TOC) removal results demonstrated that the decoloration of RhB was due to the destruction of chromophore rather than complete degradation. RhB decoloration could be significantly accelerated due to the high ionic strength. Increasing of the reaction temperature from 273 K to 333 K was beneficial to the RhB degradation, and the activation energy was determined to be 32.996 kJ/mol. Bleaching rate of RhB with the examined cations increased with the order of NH4 +?<?Na+?<?K+?<?Al3+?<?Ca2+?<?Mg2+. Some major degradation products of RhB were identified by GC-MS. The present study may have active technical implications for the treatment of dyestuff wastewater in practice.  相似文献   
128.
热处理和pH调节协同作用下污泥调质过程研究   总被引:1,自引:0,他引:1  
采用单因素实验和正交实验相结合的方式,考察了不同实验条件参数(温度、pH和反应时间)下,热处理和pH调节对污泥细胞溶出过程的影响。结果表明,污泥溶解性化学需氧量(SCOD)与反应温度、溶液pH、反应时间成正相关,其中pH对SCOD的影响最为显著,反应时间对其影响最小。污泥溶胞的最优条件:反应温度120℃,pH=11,反应时间为15 min,经过处理,SCOD可达14 810 mg/L,与总化学需氧量(TCOD)之比为49.29%,总有机碳(TOC)达4 560 mg/L,总氮(TN)则增加27%,总悬浮固体(TSS)和挥发性悬浮固体(VSS)去除率分别达22.85%和40.93%。热碱处理后污泥上清液分子量分布(MWD)状况结果显示:〉1 000 KDa MW物质含量随pH和温度的增加而增加,当pH=11时,该部分物质可从原污泥的20.94%增加到31.70%;当温度为120℃时,该部分物质可达49.83%。  相似文献   
129.
把pH值在线监测与药品自动投加系统与已开发的混合呼吸测量仪集成,组成自动呼吸-滴定测量仪,同时测得废水生物处理过程溶解氧(DO)、pH、氧气利用速率(OUR)和质子变化速率(HVR)。分别监测了只投加NH4+-N底物的活性污泥硝化过程和实验室脱氮除碳SBR曝气阶段的DO/pH响应,结果显示,两信号呈一定规律变化,在反应...  相似文献   
130.
Several investigators have developed indoor air quality questionnaires for use in field studies. The approach used in many of them have numerous features in common, but most of them are unique in their content (wording, format, item selection). It is thought that indoor air quality research could be greatly advanced if the primary or fundamental questions and instruments could be consolidated. The use of a basic set of "standard" questions would permit intercomparison of results from different research studies. It is generally agreed that environmental inventory questionnaires (EIQ) help to classify, at least in screening, relative concentration estimates, which precede exposure estimation. Thus, such instruments are not equivalent to monitoring for exposure assessment. However, data linkage and mega data bases are important for some comparative analyses of exposure assessment and exposure-response relationships. Standard instruments such as the EIQ are useful as a screening device to precede other tests to allow identification of potentially high exposure situations. They can also amplify information from other tests. General usage of standard questionnaires and protocols can lead to cumulative improvements in data collection, specificity and effectiveness. This has been the rationale for the present efforts by investigators to form a standardized environmental inventory questionnaire, under the auspices of the U.S. Environmental Protection Agency (EPA), Gas Research Institute (GRI), and Electric Power Research Institute (EPRI).  相似文献   
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