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591.
Kazuharu Yoshizuka Syouhei Nishihama Hideki Sato 《Environmental geochemistry and health》2010,32(4):297-302
The objective of this study was to survey the cation and anion contents of geothermal waters to gather fundamental information
on geographical variations. Sixteen sites in hot spring areas on the island of Kyushu in Japan were studied. The study focused
on the arsenic content of the samples. Very high arsenic concentrations (more than 0.1 mg/l) were detected in most of the
geothermal waters sampled. High contents of boron and fluoride (more than 1.0 mg/l) were also detected in some samples. Arsenic
removal was performed on a laboratory scale using columns packed with a magnetite-type adsorbent. The reduction of arsenic
contamination to a concentration of less than 0.01 mg/l could be achieved in the early stages of adsorption (bed volume = 200). 相似文献
592.
593.
594.
The inhibition and dispersion of polyepoxysuccinate (PESA, self-manufactured) to inorganic scale was evaluated by scale static beaker test to CaC03 and Ca3(P04)2, stability test to zinc salt, and dispersion test to ferric oxide. The experimental results demonstrated that PESA functioned excellent scale inhibition to CaC03 and Ca3(P04)2, good stability to zinc salt and special dispersion to ferric oxide. Under the water with hardness 500-1200 mg/L, alkalinity 1000 mg/L, and dosage of PESA 31.2 mg/L, PESA scale inhibition ratio reached more than 85.0%. At dosage of PESA 20.8 mg/L inhibition ratio on calcium phosphate reached 38.9%, at optimum dosage of PESA 9.1 mg/L, the stability ratio was up to 96.1%; while at dosage of PESA 3.6 mg/L, transmittance ratio reached 64.4%. Therefore, PESA can be considered a soluble, high effective and versatile inhibitor. 相似文献
595.
厌氧式折流反应器(Anaerobic Baffled Reactor,简称ABR)是一种新型高效厌氧反应器,具有工艺技术简单、建设投资费用低、运行管理方便、固液分离效果好、出水水质好、运行稳定可靠、对有毒物质适应性强等优点,是一种极具开发应用前景的废水生物处理新技术。ABR最大的特点是在反应器中设置上下折流板而在水流方向上形成依次串联的隔室,从而使其中的微生物种群沿长度方向的不同隔室实现产酸和产甲烷相的分离。该反应器具有结构简单,截留污泥能力强,系统处理效果稳定,运行管理方便等优点。分析了ABR及ABR与其它工艺的联合在果汁废水处理方面的应用。 相似文献
596.
The Role of Disaggregation of Asset Values in Flood Loss Estimation: A Comparison of Different Modeling Approaches at the Mulde River,Germany 总被引:3,自引:0,他引:3
Anja Wünsch Ulrich Herrmann Heidi Kreibich Annegret H. Thieken 《Environmental management》2009,44(3):524-541
In loss estimation there is a spatial mismatch of hazard data that are commonly modeled on an explicit raster level and exposure
data that are often available only for aggregated administrative units. Usually disaggregation methods that use ancillary
information to distribute lumped exposure data in a finer spatial resolution help to bridge this gap. However, the actual
influence of different mapping techniques and ancillary data on the final loss estimation has not been analyzed yet. In this
paper three methods are applied to disaggregate residential building assets using two kinds of land use/land cover (LULC)
data. The resulting disaggregated assets are validated and compared using census data of the residential building number on
the community and constituency level. In addition, the disaggregated assets are taken to estimate residential building losses
due to the flood in August 2002 in 21 municipalities on the River Mulde in Saxony, Germany. Losses are calculated with the
help of four loss models. In general, disaggregation helps to decrease the error variance within the loss estimation. It must,
however, be stated that the application of sophisticated disaggregation methods does not lead to significant improvements
compared to the straightforward binary method. Therefore more effort should instead be put into the provision of high-resolution
LULC data. Finally, the remaining uncertainties in loss estimation are high and demand further improvements in all modeling
aspects. 相似文献
597.
598.
利用PLC控制系统,实现在钢渣热焖工艺中的恒压供水和钢渣热焖定时定量喷水的自动控制要求,具有国际先进水平,取得了良好的经济效益、社会效益和环境效益. 相似文献
599.
Adaptive maritime spatial planning (MSP) uses monitoring and evaluation of the effectiveness of spatial and temporal management
measures to promote understanding and improve planning and decision-making. An adaptive approach to MSP involves exploring
alternative ways to meet management objectives, predicting the outcomes of alternative management measures, implementing one
or more of these alternative management measures, monitoring to learn about the effects of management measures, and then using
the results to update knowledge and adjust management actions. A monitoring and evaluation plan should be designed to be both
cost effective and comprehensive. The process of setting and assessing performance metrics requires that the ecological and
socio-economic objectives of the spatial management plan must be clearly stated up front for management actions to reflect
those objectives accurately. To evaluate the effectiveness of a MSP plan, a range of ecological, socio-economic and institutional
indicators need to be developed and monitored. 相似文献
600.
In this paper, we explore a range of concerns that arise in measuring short-term effects of ozone on health. In particular,
we tackle the problem of measuring exposure using alternative daily measures of ozone derived from hourly concentrations.
We adopt the exposure paradigm of Chiogna and Bellini (Environmetrics 13:55–69, 2002) extending it to ozone concentrations,
and we compare its performances with respect to traditional exposure measures by exploiting model selection. To investigate
the stability of model selection, we then apply the idea of bootstrapping the modelling process. 相似文献