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451.
阜新市工业废水污染现状及防治对策 总被引:1,自引:0,他引:1
文中对阜新市的水环境现状和存在的主要环境问题进行了系统分析,提出了解决城市工业废水污染问题和措施。并针对水资源严重匮乏地区的经济与环境协调发展问题,进行了研究和探讨。 相似文献
452.
黄山风景区旅游水供需系统安全及动态调控研究 总被引:2,自引:1,他引:2
山岳型风景区由于其独特的地形地貌条件,工程性供水难度大,随着区内床位数和游客量的不断增加,水供需矛盾更为突出,成为山岳型风景区旅游可持续发展的关键制约因素之一,黄山风景区尤具代表性。论文通过典型年分析法,对黄山风景区各月各供水片区的水供需系统进行深入分析,认为:①黄山风景区总体上供水量不足,缺水态势明显,且存在时间、空间、丰枯水期等方面的矛盾;②建立水供需动态调控模型,通过水库和引提水工程调节供水是改善黄山风景区供水短缺的重要途径;③通过现有各分片水库的调节和五里桥水库提水上山,可分别解决目前和中期供水问题,远期若建立钓桥水库,形成全山供水连片,可达到远期水供需平衡。 相似文献
453.
Biological control experiment of excess propagation of Cyclops for drinking water security 总被引:1,自引:0,他引:1
Cyclops of zooplankton propagated excessively in eutrophic water body and could not be effectively inactivated by the conventional disinfections process like chlorination due to its stronger resistance to oxidation. In this study, an ecological project was put forward for the excess propagation control of Cyclops by stocking the filter-feeding fishes such as silver carp and bighead carp under the condition of no extraneous nutrient feeding. The results of experiments with different stocking biomass showed that the propagation of Cyclops could be controlled effectively, and the water quality was improved simultaneously by impacting on nutriment level and plankton community structure at proper stocking density of 30 g/m^3 of water. The growth of Cyclops may not be effectually controlled with lower biomass of fish (10 g), and the natural food chain relation may be destroyed for Cyclops dying out in water while the intense stocking of 120 g per cubic meter of water. In addition, the high predator pressure may accelerate supplemental rate of nutrients from bottom sediments to water body to add the content of total nitrogen and phosphorus in water. 相似文献
454.
455.
Sui Pengzhe Wen Xianghua Huang Xia 《Frontiers of Environmental Science & Engineering in China》2007,1(3):362-367
In this study, ultrasound was used to control the membrane fouling online in an anaerobic membrane bioreactor (AMBR). Short-term
running experiments were carried out under different operating conditions to explore feasible ultrasonic parameters. The experimental
results indicated that when the crossflow velocity was more than 1.0 m/s, membrane fouling could be controlled effectively
only by hydrodynamic methods without ultrasound. When ultrasound was applied, an ultrasonic power range of 60–150 W was suitable
for the membrane fouling control in the experimental system. The experimental results showed that the membrane fouling was
controlled so well that membrane filtration resistance (ΣR) could stay at 5 × 1011 m−1 for more than a week with the crossflow velocity of 0.75 m/s, which equaled the effect of crossflow velocity of more than
1.0 m/s without ultrasound.
Translated from Techniques and Equipment for Environmental Pollution Control, 2006, 7(4): 25–29 [译自: 环境污染治理技术与设备] 相似文献
456.
龙川江水质污染状况、发展趋势及水污染防治对策 总被引:1,自引:0,他引:1
通过对龙川江水质监测资料、水环境状况调查情况的分析,对龙川江水质发展趋势进行了评价和分析,提出龙川江水环境污染防治的对策。 相似文献
457.
湘潭市酸雨污染状况、化学组成及其防治对策 总被引:1,自引:0,他引:1
根据2001—2005年湘潭市城区降水环境质量监测数据,对湘潭城区酸性降水的变化特征、离子化学组成、变化趋势和酸雨成因进行了分析。“十五期间”湘潭市区酸雨频率在50%以上,pH值平均范围在4.56—4.91,属重酸雨区;SO4^2-/NO3^-比值为4.93~6.13,属典型硫酸型;湘潭城区酸雨有明显的季节变化规律,春季和冬季酸雨出现的频率最多,秋季最少;酸雨分布没有明显的地区差异。依据相关系数法检验,湘潭市的酸雨从总体上看污染趋势无显著性变化,呈现相对稳定状态。 相似文献
458.
介绍了LS氨法喷雾烟气脱硫技术在云南解化集团有限公司的使用情况,针对化工企业实际情况和应用过程中出现的问题,提出改进措施和技术创新,使该项技术在应用中更加完善。 相似文献
459.
Tineke H. Jones Alain Houde Elyse Poitras Pierre Ward Michael W. Johns 《Food and environmental virology》2009,1(2):57-65
There are increasing concerns of zoonotic transmission of some animal enteric viruses, such as calicivirus, hepatitis E virus,
and rotavirus, which are closely related to human pathogenic strains. Most enteric viruses are detected by molecular techniques
because they cannot be cultured. Surrogates such as F-RNA coliphages are cultivable but few molecular methods exist. Individual
real-time TaqMan RT-PCR assays for the replicase gene of F-RNA coliphage genogroups I and IV were developed and multiplexed
with a real-time TaqMan RT-PCR assay for feline calicivirus as a sample process control for the simultaneous detection and
enumeration of genogroup I and IV F-RNA coliphages. Genogroup IV were successfully detected with the multiplexed assay in
80% of fecal samples that contained F-RNA coliphage levels ≥3.2 log plaque forming units (pfu). F-RNA coliphage were at or
below the limit of detection in most fecal samples when levels were ≤4 log pfu/g. 相似文献
460.
Prodigiosin is a reddish antibiotic pigment that plays an important role in the biocontrol of plant diseases by the bacterium
Serratia marcescens. However, its activity is unstable under agricultural conditions; further, it can be degraded by various environmental factors.
To examine the effect of epiphytic microbes on the stability of prodigiosin used for biological control processes, we collected
a total of 1,280 bacterial isolates from the phylloplane of cyclamen and tomato plants. Approximately 72% of the bacterial
strains isolated from the cyclamen plants and 66% of those isolated from the tomato plants grew on minimal agar medium containing
100 μg ml−1 prodigiosin. Certain isolates obtained from both plant species exhibited prodigiosin-degrading activity. We compared the
16S rRNA gene sequences derived from the isolates with sequences in a database. The comparison revealed that the sequences
determined for the prodigiosin-degrading isolates were homologous to those of the genera Pseudomonas, Caulobacter, Rhizobium, Sphingomonas, Janthinobacterium, Novosphingobium, and Rathayibacter. These results indicate that indigenous epiphytic microorganisms may interfere with the interaction between plant pathogens
and biocontrol agents by degrading the antibiotics produced by the agents. 相似文献