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悬浮填料活性污泥法影响因素初探 总被引:6,自引:0,他引:6
针对传统活性污泥法生物脱氮除磷功能较差,前期试验和中试试验采用投加悬浮填料强化其脱氮能力,进而研究了曝气方式对生物膜量的影响,及低温、填料投配比和生物膜量等因素对系统脱氮效果的影响。结果表明,采用微孔曝气能显著提高填科的生物膜量,而在一定范围内降低填科投配比对系统硝化效果影响不大,冬季通过提高系统的曝气量,可以保证系统的硝化效果基本不变,使出水氨氮较低,出水完全可以达标排放,表明试验投加悬浮填科强化传统活性污泥法的脱氮功能是经济,简便和可行的。 相似文献
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Juan Xie Xinyu Zhang Zhiwei Xu Guofu Yuan Xinzhai Tang Xiaomin Sun D. J. Ballantine 《Frontiers of Environmental Science & Engineering》2014,8(4):561-569
The concentrations of total phosphorus (TP) from 83 surface water sampling sites in 29 of the Chinese Ecosystem Research Network (CERN) monitored ecosystems, representing typical agro- and forest ecosystems, were assessed using monitoring data collected between 2004 and 2010 from still and flowing surface water. Results showed that, TP concentrations were significantly higher in agro-ecosystems than those in forest ecosystems both for still and flowing surface water. For agro- ecosystems, TP concentrations in the southern area were significantly higher than those in the northern and north- western areas for both still and flowing surface water, however no distinct spatial pattern was observed for forest ecosystems. In general, the median values of TP within agro- and forest ecosystems did not exceed the Class V guideline for still (0.2mg.L-1) or flowing (0.4mg.L-1) surface water, however, surface water at some agro- ecosystem sampling sites was frequently polluted by TE Elevated concentrations were mainly found in still surface water at the Changshu, Fukang, Linze and Naiman monitored ecosystems, where exceedance (〉 0.2 mg.L-1) frequencies varied from 43% to 78%. For flowing water, elevated TP concentrations were found at the Hailun, Changshu and Shapotou monitored ecosystems, where exceedance (〉 0.4 mg. L-1) frequencies varied from 29% to 100%. Irrational fertilization, frequent irrigation and livestock manure input might be the main contributors of high TP concentrations in these areas, and reduced fertilizer applications, improvements in irrigation practices and centralized treatment of animal waste are necessary to control P loss in these TP vulnerable zones. 相似文献
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利用1961~2006年陇东黄土高原气象观测站的雷暴资料,运用数理统计、函数分解、图表分析方法,分析了雷暴的时空分布特征.(结果表明:陇东雷暴次数的年际变化总体上呈波动状态,60年代为雷暴多发期,70年代波动明显,大致存在4.5年的振荡周期,80年代为增长期,以5年为周期振荡,90年代开始至今以4年为周期振荡并呈现减少趋势.根据41年NCEP/NCAR再分析格点资料,并考虑下垫面热力作用,用统计分析方法得到判别陇东黄土高原雷暴有无的预报函数,建立了雷暴短期短时预报的判别模型.检验表明:雷暴短期短时预报模型是可行的,2005~2006年试报,雷暴预报出现宰可达61.7%,在同一时效下模型的预报水平要高于预报员的主观预报. 相似文献
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为了解决喜旱莲子草入侵带来的环境污染和生态破坏问题,探索了综合利用其制备价廉、质优活性炭的可能性、在正交实验的基础上,对实验结果进行了单因素方差分析,结果表明,控制因素对活性炭得率和碘吸附值的影响大小均依次为:炭化温度>炭化时间>浸渍时间>浸渍比,且前三者有显著影响、极差分析表明最佳制备工艺组合为:浸溃比4∶1、浸渍时间6h、炭化温度873 K和炭化时间1h.在最佳制备条件下制得的喜旱莲子草基活性炭得率和碘吸附值为:37.44%和752.36 mg/g;其比表面积、总孔体积、平均孔径和中孔率分别为:1 100.720 m2/g、0.610 cm3/g、2.216 nm、72.00%.红外光谱分析表明,活性炭形成了大量表面官能团,主要有以下几种:羧基、酚基、醚基等、正交实试和物理特性表征均表明,喜旱莲子草是良好的中孔活性炭制备原料. 相似文献
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Hui Xue Xiaoyi Ren Shiyu Li Xu Wu Hao Cheng Bin Xu Baojing Gu Guofu Yang Changhui Peng Ying Ge Jie Chang 《Environmental monitoring and assessment》2013,185(10):8501-8516
Tea plantations are rapidly expanding in China and other countries in the tropical and subtropical zones, driven by relatively high private economic benefit. However, the impact of tea plantations on the regional environment, including ecosystem services and disservices are unclear. In this study, we developed an assessment framework for determining the private economic benefits and environmental externalities (the algebraic sum of the regulating services and disservices) of tea plantations in China. Our results showed that tea plantations provided private economic benefits of 5,652 yuan ha?1 year?1 (7.6 yuan?=?1 USD in 2007) for tea farmers, plus positive environmental externalities of 6,054 yuan ha?1 year?1 for the society. The environmental externalities were calculated as the sum of the value of four regulating services, including carbon sequestration (392 yuan ha?1 year?1); soil retention (72 yuan ha?1 year?1); soil fertility protection (3,189 yuan ha?1 year?1) and water conservation (2,685 yuan ha?1 year?1), and three disservices, including CO2 emission (?39 yuan ha?1 year?1), N2O emission (?137 yuan ha?1 year?1) and nonpoint source pollution (?108 yuan ha?1 year?1). Before the private optimal level, the positive environmental externalities can be maintained by private economic benefits; if a social optimal level is required, subsidies from government are necessary. 相似文献
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Chunyun Zhang Guofu Chen Chaoshuai Ma Yuanyuan Wang Baoyu Zhang Guangce Wang 《Environmental science and pollution research international》2014,21(6):4565-4575
Harmful algal blooms (HABs) are a global problem, which can cause economic loss to aquaculture industry's and pose a potential threat to human health. More attention must be made on the development of effective detection methods for the causative microalgae. The traditional microscopic examination has many disadvantages, such as low efficiency, inaccuracy, and requires specialized skill in identification and especially is incompetent for parallel analysis of several morphologically similar microalgae to species level at one time. This study aimed at exploring the feasibility of using membrane-based DNA array for parallel detection of several microalgae by selecting five microaglae, including Heterosigma akashiwo, Chaetoceros debilis, Skeletonema costatum, Prorocentrum donghaiense, and Nitzschia closterium as test species. Five species-specific (taxonomic) probes were designed from variable regions of the large subunit ribosomal DNA (LSU rDNA) by visualizing the alignment of LSU rDNA of related species. The specificity of the probes was confirmed by dot blot hybridization. The membrane-based DNA array was prepared by spotting the tailed taxonomic probes onto positively charged nylon membrane. Digoxigenin (Dig) labeling of target molecules was performed by multiple PCR/RT-PCR using RNA/DNA mixture of five microalgae as template. The Dig-labeled amplification products were hybridized with the membrane-based DNA array to produce visible hybridization signal indicating the presence of target algae. Detection sensitivity comparison showed that RT-PCR labeling (RPL) coupled with hybridization was tenfold more sensitive than DNA-PCR-labeling-coupled with hybridization. Finally, the effectiveness of RPL coupled with membrane-based DNA array was validated by testing with simulated and natural water samples, respectively. All of these results indicated that RPL coupled with membrane-based DNA array is specific, simple, and sensitive for parallel detection of microalgae which shows promise for monitoring natural samples in the future. 相似文献