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551.
分析了目前锦州市环境监测工作所面临的形势、监测能力现状及突出存在的问题.提出了以“三个说得清”为目标,统筹协调,扎实工作,在即将到来的“十三五”,明确未来五年质量控制工作重点,加强环境监测能力建设,提升影响力,充分适应社会发展要求以及科学技术的日益进步和监测技术的不断更新,切实提高综合监测能力和整体水平,细化目标责任考核细则,切实抓好“内强素质、外树形象”工作,使环境监测工作再上新台阶. 相似文献
552.
采用驯化SBR法来处理明胶生产工序段的磷钙水,研究了该法的可行性及污泥活性抑制后的恢复措施。结果表明:驯化SBR法处理磷钙废水有一定的处理效果,COD去除率最高可达88%,除磷效果明显,24h去除率维持在85%;反应器运行7~8天后,污泥活性受高氯根和碳酸钙的积累而被抑制,经更换部分污泥和添加低浓度废水等措施,可使污泥生物活性得到恢复。 相似文献
553.
Lake Taihu, a large, shallow hypertrophic freshwater lake in eastern China, has experienced lake-wide toxic cyanobacterial blooms annually during summer season in the past decades. Spatial changes in the abundance of hepatotoxin microcystin-producing and non-microcystin producing Microcystis populations were investigated in the lake in August of 2009 and 2010. To monitor the densities of the total Microcystis population and the potential microcystin-producing subpopulation, we used a quantitative real-time PCR assay targeting the phycocyanin intergenic spacer (PC-IGS) and the microcystin synthetase gene (mcyD), respectively. On the basis of quantification by real-time PCR analysis, the abundance of potential toxic Microcystis genotypes and the ratio of the mcyD subpopulation to the total Microcystis varied significantly, from 4.08× 104 to 5.22× 107 copies/mL, from 5.7% to 65.8%, respectively. Correlation analysis showed a strong positive relationship between chlorophyll-a, toxic Microcystis and total Microcystis; the abundance of toxic Microcystis correlated positively with total phosphorus and ortho-phosphate concentrations, but negatively with TN:TP ratio and nitrate concentrations. Meanwhile the proportion of potential toxic genotypes within Microcystis population showed positive correlation with total phosphorus and ortho-phosphate concentrations. Our data suggest that increased phosphorus loading may be a significant factor promoting the occurrence of toxic Microcystis bloom in Lake Taihu. 相似文献
554.
The linear accumulation of atmospheric mercury by vegetable and grass leaves: Potential biomonitors for atmospheric mercury pollution 总被引:3,自引:0,他引:3
Zhenchuan Niu Xiaoshan Zhang Sen Wang Zhijia Ci Xiangrui Kong Zhangwei Wang 《Environmental science and pollution research international》2013,20(9):6337-6343
One question in the use of plants as biomonitors for atmospheric mercury (Hg) is to confirm the linear relationships of Hg concentrations between air and leaves. To explore the origin of Hg in the vegetable and grass leaves, open top chambers (OTCs) experiment was conducted to study the relationships of Hg concentrations between air and leaves of lettuce (Lactuca sativa L.), radish (Raphanus sativus L.), alfalfa (Medicago sativa L.) and ryegrass (Lolium perenne L.). The influence of Hg in soil on Hg accumulation in leaves was studied simultaneously by soil Hg-enriched experiment. Hg concentrations in grass and vegetable leaves and roots were measured in both experiments. Results from OTCs experiment showed that Hg concentrations in leaves of the four species were significantly positively correlated with those in air during the growth time (p?<?0.05), while results from soil Hg-enriched experiment indicated that soil-borne Hg had significant influence on Hg accumulation in the roots of each plant (p?<?0.05), and some influence on vegetable leaves (p?<?0.05), but no significant influence on Hg accumulation in grass leaves (p?>?0.05). Thus, Hg in grass leaves is mainly originated from the atmosphere, and grass leaves are more suitable as potential biomonitors for atmospheric Hg pollution. The effect detection limits (EDLs) for the leaves of alfalfa and ryegrass were 15.1 and 22.2 ng g–1, respectively, and the biological detection limit (BDL) for alfalfa and ryegrass was 3.4 ng m–3. 相似文献
555.
为了开发除磷填料,以红壤为基本材料,并以烧结温度、粉煤灰添加量、外加剂A用量和外加剂B用量作为4个因素设计正交实验,制造了不同配方的红壤烧结填料,进行等温吸附实验并利用Langmuir模型拟合最大吸磷量进行比较。结果表明,通过烧结可使粉末状红壤成型,同时提高了其除磷能力;对填料理论吸磷量的影响因素主次顺序为外加剂B用量、外加剂A用量、粉煤灰用量及烧结温度;通过比较理论吸附量,同时考虑到成本,可以确定正交实验结果中较优填料配方组成为(重量比):61%红壤,30%粉煤灰,0%外加剂A,9%外加剂B,烧结温度1150℃,其最大理论的磷吸附量2.274mg/cm^2,单位除磷原料成本约0.047元/g. 相似文献
556.
Distribution and accumulation of endocrine-disrupting chemicals and pharmaceuticals in wastewater irrigated soils in Hebei, China 总被引:3,自引:0,他引:3
Chen F Ying GG Kong LX Wang L Zhao JL Zhou LJ Zhang LJ 《Environmental pollution (Barking, Essex : 1987)》2011,159(6):1490-1498
This study investigated the occurrence of 43 emerging contaminants including 9 endocrine-disrupting chemicals and 34 pharmaceuticals in three sites in Hebei Province, north China. Each site has a wastewater irrigated plot and a separate groundwater irrigated plot for comparison purpose. The results showed that the concentrations of the target compounds in the wastewater irrigated soils were in most cases higher than those in the groundwater irrigated soils. Among the 43 target compounds, nine compounds bisphenol-A, triclocarban, triclosan, 4-nonylphenol, salicylic acid, oxytetracycline, tetracycline, trimethoprim and primidone were detected at least once in the soils. Preliminary environmental risk assessment showed that triclocarban might pose high risks to terrestrial organisms while the other detected compounds posed minimal risks. Irrigation with wastewater could lead to presence or accumulation of some emerging contaminants to some extent in irrigated soils. 相似文献
557.
Two types of nano-pore substrates, waste-reclaimed (WR) and soil mineral (SM) with the relatively low density, were modified by the reaction with irons (i.e. Fe(II):Fe(III) = 1:2) and the applicability of the modified substrates (i.e. Fe-WR and Fe-SM) on cyanide removal was investigated. Modification (i.e. Fe immobilization on substrate) decreased the BET surface area and PZC of the original substrates while it increased the pore diameter and the cation exchange capacity (CEC) of them. XRD analysis identified that maghemite (γ-Fe2O3) and iron silicate composite ((Mg, Fe)SiO3) existed on Fe-WR, while clinoferrosilite (FeSiO3) was identified on Fe-SM. Cyanide adsorption showed that WR adsorbed cyanide more favorably than SM. The adsorption ability of both original substrates was enhanced by the modification, which increased the negative charges of the surfaces. Without the pH adjustment, cyanide was removed as much as 97% by the only application of Fe-WR, but the undesirable transfer to hydrogen cyanide was possible because the pH was dropped to around 7.5. With a constant pH of 12, only 54% of cyanide was adsorbed on Fe-WR. On the other hand, the pH was kept as 12 without adjustment in Fe-WR/H2O2 system and cyanide was effectively removed by not only adsorption but also the catalytic oxidation. The observed first-order rate constant (kobs) for cyanide removal were 0.49 (±0.081) h−1. Moreover, the more cyanate production with the modified substrates indicated the iron composites, especially maghemite, on substrates had the catalytic property to increase the reactivity of H2O2. 相似文献
558.
活性炭和沸石对氨氮的吸附特性及生物再生 总被引:5,自引:1,他引:4
采用活性炭和沸石作为吸附材料,分别考察了这两种吸附材料对水体中氨氮的吸附特性及其生物再生性能。实验结果表明,活性炭和沸石对水体中氨氮的等温吸附符合Freundlich等温式,其拟合度分别为0.9783和0.9303;静态吸附结果表明活性炭和沸石均具有较好的氨氮吸附性能,24 h内沸石对氨氮的吸附能力为1.27 mg/g,高于活性炭的0.53 mg/g;动态吸附中沸石达到吸附饱和的时间为96 h,较活性炭达到吸附饱和的时间长,沸石显示出作为氨氮吸附剂的优越性;活性炭和沸石经过96 h的生物再生后吸附性能获得一定程度的再生,出水中氨氮浓度比未进行生物再生前分别降低17.31 mg/L和8.32 mg/L,且都在表面形成了稳定的生物膜。 相似文献
559.
Robert S. Wright Emery J. Kong Mark A. Bahner C. Andrew Clayton Carlos M. Nuñez Geddes H. Ramsey 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1110-1115
ABSTRACT Research Triangle Institute and the U.S. Environmental Protection Agency conducted several projects to measure hydrocarbon emissions associated with the manufacture of fiberglass-reinforced plastics. The purpose of these projects was to evaluate pollution prevention techniques to reduce emissions by altering raw materials, application equipment, and operator technique. Analytical techniques were developed to reduce the cost of these emission measurements. Emissions from a small test mold in a temporary total enclosure (TTE) correlated with emissions from full-size production molds in a separate TTE. Gravimetric mass balance measurements inside the TTE generally agreed to within ± 30 % with total hydrocarbon (THC) measurements in the TTE exhaust duct. Pure styrene evaporation tests served as quality control checks for THC measurements and generally agreed to within ± 5 %. 相似文献
560.