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71.
膜生物反应器技术在环境激素废水处理中的应用   总被引:1,自引:0,他引:1  
本文主要介绍膜生物反应器技术在环境激素废水处理研究中的应用现状。  相似文献   
72.

The core zone of the Yancheng National Natural Reserve (YNNR) in China is the largest wintering habitat of red-crowned cranes (cranes) in the world. However, the invasion of Spartina alterniflora (S. alterniflora) not only changed the original landscape structure of the wetlands but also impacted the cranes’ habitats in the YNNR. In this paper, field investigation data and landscape pattern indices were used to analyze the effects of the S. alterniflora invasion on the habitat quality of wintering cranes. The results indicate that the seep weed (Suaeda salsa) in the natural wetland and the common reed (Phragmites australis) in the managed wetland both provide suitable habitats for cranes. However, the cranes prefer the natural wetland more. The explosive growth of S. alterniflora in the natural area has led to a significant reduction of the cranes’ habitat. The area of crane habitat decreased from 52.07 km2 in 2000 to 22.36 km2 in 2015. As a result of the S. alterniflora invasion, the benthic biomass has declined, which has negatively impacted the quantity and structure of the food utilized by the cranes. This study has both theoretical and practical significance and provides a scientific basis for protecting the wintering habitat of the red-crowned cranes.

  相似文献   
73.
铁屑过滤-SBR工艺处理印染废水的研究   总被引:22,自引:0,他引:22  
采用铁屑过滤-SBR工艺对印染废水进行了处理研究,当进水COD为1000-1600mg/L,色度为200-800倍,BOD5在200-400mg/L时,COD去除率可达85%,BOD5去除率和脱色率均在90%以上,出水达到排放标准,该工艺具有投资少,运行费用低,处理效果稳定等特点,尤其适合中小型印染厂的废水治理。  相似文献   
74.
采用中温焙烧/钠化氧化法从电镀污泥中回收铬.结果表明,影响铬浸出率的最主要因素为焙烧温度.电镀污泥与碳酸钠质量比、焙烧时间、水浸时间对铬浸出率的影响较接近,在水浸水固比为10.0 ; 1.0(质量比)、室温、焙烧温度为650℃、焙烧时间为2.0h、电镀污泥与碳酸钠质量比为1:1、水浸时间为60 min的最佳浸出条件下,铬浸出率为99.3%;去除氢氧化铝、氢氧化锌的最佳反应温度和pH分别为90~95℃和7.5;去除硫酸钠晶体的最佳pH为4.0,在最佳试验条件下,铬回收率为90.57%.  相似文献   
75.
A greenhouse pot experiment was conducted to investigate the effects of the colonization of arbuscular mycorrhizal fungus (AMF) Glomus mosseae on the growth and metal uptake of three leguminous plants (Sesbania rostrata, Sesbania cannabina, Medicago sativa) grown in multi-metal contaminated soil. AMF colonization increased the growth of the legumes, indicating that AMF colonization increased the plant’s resistance to heavy metals. It also significantly stimulated the formation of root nodules and increased the N and P uptake of all of the tested leguminous plants, which might be one of the tolerance mechanisms conferred by AMF. Compared with the control, colonization by G. mosseae decreased the concentration of metals, such as Cu, in the shoots of the three legumes, indicating that the decreased heavy metals uptake and growth dilution were induced by AMF treatment, thereby reducing the heavy metal toxicity to the plants. The root/shoot ratios of Cu in the three legumes and Zn in M. sativa were significantly increased (P < 0.05) with AMF colonization, indicating that heavy metals were immobilized by the mycorrhiza and the heavy metal translocations to the shoot were decreased.  相似文献   
76.
Fluence rate (FR) distribution (optical field) is of great significance in the optimal design of ultraviolet (UV) reactors for disinfection or oxidation processes in water treatment. Since the 1970s, various simulation models have been developed, which can be combined with computational fluidic dynamic software to calculate the fluence delivered in a UV reactor. These models strive for experimental validation and further improvement, which is a major challenge for UV technology in water treatment. Herein, a review of the simulation models of the FR distribution in a UV reactor and the applications of the current main experimental measurement approaches including conventional flat-type UV detector, spherical actinometer, and micro-fluorescent silica detector (MFSD), is presented. Moreover, FR distributions in a UV reactor are compared between various simulation models and MFSD measurements. In addition, the main influential factors on the FR distribution, including inner-wall reflection, refraction and shadowing effects of adjacent lamps, and turbidity effect are discussed, which is helpful for improving the accuracy of the simulation models and avoiding dark regions in the reactor design. This paper provides an overview on the simulation models and measurement approaches for the FR distribution, which is helpful for the model selection in fluence calculations and gives high confidence on the optimal design of UV reactors in regard to present methods.  相似文献   
77.
78.
加强环境监测的全过程质量管理   总被引:5,自引:0,他引:5  
楼燕 《环境科学与管理》2008,33(12):140-141
质量管理是环境监测赖以生存和发展的基础,目前,环境监测质管工作中“重结果、轻过程”的问题仍然普遍存在,加强全过程质量管理才能确保监测数据的准确性和可靠性,为实现环境资源的可持续利用提供强有力的技术支撑。文章叙述了环境监测质量管理的发展概况,引出全过程质量管理的概念,提出从提高全员质量意识、建立健全质量管理体系、实施全过程的质量保证、加大质控工作力度等几方面加强环境监测的全过程质量管理,从而提升环境监测机构整体质量管理水平。  相似文献   
79.
本文分析了龙江县水土流失的成因及危害,并提出了机关的防治对策,对今后的水土保养、合理开发有一定的借鉴作用.  相似文献   
80.
引水工程前后西湖流场的数值模拟研究   总被引:1,自引:0,他引:1  
采用Delft 3D水动力学计算模型,对西湖西进工程前后的流场进行了模拟,计算结果与实测资料较为吻合,模型真实可靠.各种工况下的流场模拟结果表明在不考虑风场的情况下,各进出水口的流量和位置决定了西湖的流场结构,而流场结构决定了水体的推移扩散规律.总体上,南湖水体推移扩散效果最好,西里湖、外湖和岳湖次之,北里湖最差,基本不能被置换.西湖水体的置换效果主要取决于可被置换区域的面积和引水量,而可被置换区域大小主要取决于流场结构.因此,在引水量不变的前提下,优化西湖水体置换效果的根本途径就是调整进出水口位置和流量大小,以改变流场结构.  相似文献   
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