古运河(镇江段)沉积物酶活性及其与氮磷阴离子的相关性

以古运河镇江段为研究对象,研究了表层沉积物中碱性磷酸酶活性、硝酸还原酶活性和亚硝酸还原酶活性的时空变化以及3种酶活性与河流表层沉积物中氮磷阴离子浓度及上覆水水质的相关性。结果表明,镇江古运河表层沉积物中碱性磷酸酶活性、硝酸还原酶活性和亚硝酸还原酶活性具有显著的时间和区域性差异,枯水期(12月)各酶活性较高,分别介于0.29~0.32 mg/(g·24 h)、0.13~0.19 mg/(g·24 h)、3.05~5.21 mg/(g·24 h);丰水期(5月)各酶活性较低,变化范围分别为0.18~0.29 mg/(g·24 h)、0.08~0.14 mg/(g·24 h)、2.95~3.64 mg/(g·24 h)。冗余分析结果显示,古运河表层沉积物酶活性在枯水期差异较大,丰水期差异较小,各酶活性与其相关离子浓度呈显著正相关(P0.05),硝酸还原酶和亚硝酸还原酶与上覆水的水质呈正相关。3种酶活性可被作为判断古运河镇江段沉积物富营养化负荷的参考性指标,硝酸还原酶和亚硝酸还原酶还可作为评价古运河镇江段水质的参考性指标。     

Removal potential of anti-estrogenic activity in secondary effluents by coagulation

Anti-estrogenic activity in wastewater is gaining increased attention because of its endocrine-disrupting function. In this study, the level and removal efficiency by coagulation of anti-estrogenic activity in secondary effluents of domestic wastewater treatment plants were studied. Anti-estrogenic activity was detected in secondary effluent samples at a tamoxifen (TAM) equivalent concentration level of 0.38–0.94 mg-TAM L⁻¹. Dissolved organic matters (DOM) with the molecular weight (MW) less than 3000 Da in hydrophobic acids (HOA) and hydrophobic neutrals (HON) fractions of the secondary effluent were the key fractions related to anti-estrogenic activity. Coagulation with FeCl₃ and polyaluminium chloride (PAC) can remove the anti-estrogenic activity of the secondary effluents, but the removal efficiency was limited. The removal efficiency using FeCl₃ coagulant was higher than that induced by PAC. Dissolved organic carbon was continuously removed with increased coagulant dose (0–120 mg L⁻¹ FeCl₃ or 0–60 mg L⁻¹ PAC). However, the removal of anti-estrogenic activity was not enhanced further when the coagulant concentration was beyond a critical value (30 mg L⁻¹ FeCl₃ or 10 mg L⁻¹ PAC). The highest removal of anti-estrogenic activity was about 36% by FeCl₃ and 20% by PAC. Size exclusion chromatography results indicated difficulty in removing DOM with MW less than 3000 Da in the secondary effluent during coagulation even at a high coagulant concentration, which led to low removal efficiency of anti-estrogenic activity.     

Effect of Pencycuron on Microbial Parameters of Waterlogged Soil

A laboratory study was conducted to monitor the effect of pencycuron [1-(4-chlorobenzyl)-1-cyclopentyl-3-phenylurea] on microbial parameters of alluvial (AL) soil (Typic udifluvent) and coastal saline (CS) soil (Typic endoaquept) under waterlogged condition. Pencycuron at field rate (FR), 2FR and 10FR affected the microbial biomass C (MBC), soil ergosterol content and fluorescein diacetate hydrolyzing activity (FDHA) differentially. The DCM amendment did not seem to have any counteractive effect on the toxicity of pencycuron on the microbial variables. The change in microbial metabolic quotient (qCO₂) and microbial respiration quotient (Q_R), indicated pencycuron induced disturbance at 10FR. Present study revealed that the metabolically activated microbial population was more suppressed compared to the dormant population.     

Feeding of western gray whales during a seismic survey near Sakhalin Island, Russia

Exxon Neftegas Limited, as operator of the Sakhalin-1 consortium, is developing oil and gas reserves on the continental shelf off northeast Sakhalin Island, Russia. DalMorNefteGeofizika (DMNG) on behalf of the Sakhalin-1 consortium conducted a 3-D seismic survey of the Odoptu license area during 17 August–9 September 2001. A portion of the primary feeding area of the endangered western gray whale (Eschrichtius robustus) is located in the vicinity of the seismic survey. This paper presents data to assess whether western gray whale bottom feeding activity, as indicated by visible mud plumes, was affected by seismic operations. The mitigation and monitoring program associated with the seismic survey included aerial surveys during 19 July–19 November 2001. These aerial surveys documented the local and regional distribution, abundance, and bottom feeding activity of western gray whales. Data on gray whale feeding activity before, during and after the seismic survey were collected, with the whales assumed to be feeding on the benthos if mud plumes were observed on the surface. The data were used to assess the influence of seismic survey and other factors (including environmental) on feeding activity of western gray whales. A stepwise multiple regression analysis failed to find a statistically significant effect (α = 0.05) of the seismic survey on frequency of occurrence of mud plumes of western gray whales used as a proxy to evaluate bottom feeding activity in Piltun feeding area. The regression indicated that transect number (a proxy for water depth, related to distance from shore) and swell height (a proxy for sea state) were the only variables that had a significant effect on frequency of whale mud plumes. It is concluded that the 2001 seismic survey had no measurable effect (α = 0.05) on bottom feeding activity of western gray whales off Sakhalin Island. M.W. Newcomer, deceased     

Integrated Ambient and Microenvironment Model for Estimation of PM10 Exposures of Children in Annual and Episode Settings

Particulate matter air pollution is estimated to cause in the order of 350,000 excess deaths in the European Union calling for policy development and evaluation tools. In the current work, a model for PM₁₀ exposures of children is developed using microenvironment time activities and infiltration of ambient pollution indoors, both evaluated against observations earlier and integrated with city-wide air quality models in the current work. The model is demonstrated using data from two cities in Italy. High-end short-term exposures are characterized by an episode-day situation in Turin, and annual mean exposures in downtown Bologna. The air quality model was unable to capture the highest levels during the episode, and therefore, the exposure model was adjusted using observed–modeled ratio from a monitoring station. Air quality model performance for the annual levels was significantly better. Annual exposure variability within the target population was 1.5-fold in the downtown area Bologna and tenfold during the episode day in Turin.     

Analysis of gross alpha, gross beta activities and beryllium-7 concentrations in surface air: their variations and statistical prediction model

Measurement of gross α, gross β activities and cosmogenic beryllium-7 (⁷Be) concentrations were made both daily and weekly during the years 2001–2004 from samples of atmospheric aerosols filtered from the air at Tehran Nuclear Research Center (35 41′ N) and Zahedan (28 29′ N). Weekly aerosol samples collected with the high-volume air samplers on cellulose filters were used to determine the ⁷Be contents of samples, using a semiconductor gamma spectrometer. Airborne dust samples were collected daily on fiber glass filters and used to determine the gross β and gross α activities with automatic beta analyzer and a ZnS(Ag) counter, respectively. In this work, the concentration and meteorological data were used to determine models for gross α, gross β and ⁷Be. The air concentrations of gross β and gross α activities and ⁷Be concentrations displayed lognormal distributions during the study period. Both β and ⁷Be have maximum activity concentrations during warm mid-year months.     

Chlorpyrifos degradation in a biomixture of biobed at different maturity stages

The biomixture is a principal element controlling the degradation efficacy of the biobed. The maturity of the biomixture used in the biobed affects its overall performance of the biobed, but this is not well studied yet. The aim of this research was to evaluate the effect of using a typical composition of Swedish biomixture at different maturity stages on the degradation of chlorpyrifos. Tests were made using biomixture at three maturity stages: 0 d (BC0), 15 d (BC15) and 30 d (BC30); chlorpyrifos was added to the biobeds at final concentration of 200, 320 and 480 mg kg⁻¹. Chlorpyrifos degradation in the biomixture was monitored over time. Formation of TCP (3,5,6-trichloro-2-pyrinidol) was also quantified, and hydrolytic and phenoloxidase activities measured. The biomixture efficiently degraded chlorpyrifos (degradation efficiency >50%) in all the evaluated maturity stages. However, chlorpyrifos degradation decreased with increasing concentrations of the pesticide. TCP formation occurred in all biomixtures, but a major accumulation was observed in BC30. Significant differences were found in both phenoloxidase and hydrolytic activities in the three maturity stages of biomixture evaluated. Also, these two biological activities were affected by the increase in pesticide concentration. In conclusion, our results demonstrated that chlorpyrifos can be degraded efficiently in all the evaluated maturity stages.     

超声辐射浸渍法制备Fe-Ni-Mn/Al2O3催化剂及性能研究

以Al2O3为载体,分别采用超声辐射浸渍法和普通浸渍方法制备Fe-Ni-Mn/Al2O3催化剂。采用BET、XRD和SEM对催化剂的理化性质和孔结构进行了分析,以模拟酸性绿B废水为研究对象考察催化剂的催化性能。实验结果表明,浸渍溶液pH值和焙烧温度显著影响催化剂的性能。与普通浸渍法相比,超声浸渍法制备的Fe-Ni-Mn/Al2O3催化剂对酸性绿B脱色反应表现出较高的催化活性。     

Synthesis and pesticidal activity of new N-alkyl-N-[1-(2-hydroxyphenyl) ethyl]amines

A series of novel N-alkyl-N-[1-(2-hydroxyphenyl) ethyl]amines were synthesized as potential new agents to control pests. Their structures were confirmed on the basis of IR, NMR and elemental analyses. Six new N-alkyl-N-[1-(2-hydroxyphenyl) ethyl]amines were prepared by reduction of corresponding Schiff bases using sodium borohydride in 80–87 % yields. These compounds were tested for their antifungal activity against two pathogenic fungi viz., Rhizoctonia bataticola ITCC 0482 and Sclerotium rolfsii ITCC 5226 and for insecticidal activity against insects of stored grain pest Callosobruchus analis. Fungicidal bioassay revealed that compound N-Decyl-N-[1-(2-hydroxyphenyl)ethyl]amine, was highly effective against R. bataticola (ED₅₀ 6.86 mg L^?1) which was comparable with that of commercial fungicide hexaconazole (ED₅₀ 6.35 mg L^?1). Also compounds N-Heptyl-N-[1-(2-hydroxyphenyl)ethyl]amine, N-Octyl-N-[1-(2-hydroxyphenyl)ethyl]amine and N-Nonyl-N-[1-(2-hydroxyphenyl)ethyl]amine displayed promising fungitoxicity against same pathogen. However, compound N-Heptyl-N-[1-(2-hydroxyphenyl)ethyl]amine was also found to be effective against S. rolfsii (ED₅₀ 4.92 mg L^?1 as against 1.27 mg L^?1 for hexaconazole). Compound N-Hexyl-N-[1-(2-hydroxyphenyl)ethyl]amine was most effective as insecticide followed by compound N-Octyl-N-[1-(2-hydroxyphenyl)ethyl]amine. LC₅₀ values for these compounds were 155.0 and 275.0 mg L^?1 respectively as against 36.70 mg L^?1 for commercial insecticide dichlorovos. The results obtained from bioassays indicate that this class of compounds can be utilized for the design of new substances endowed with pesticidal activities.     

DIFFERENTIAL EFFECTS OF THE HERBICIDES BENSULFURON AND CINOSULFURON ON SOIL MICROORGANISMS

Bensulfuron toxicity on soil microbes was evaluated by the methods used in a previous study on cinosulfuron; the effects of the two sulfonylureas were compared. Cinosulfuron and bensulfuron, at the normal field application rate and 100 times higher, had no effect on the total number of bacteria and nitrifiers, or on the respiration activity in the soil, but they did decrease the nitrification activity. In vitro toxicity tests carried out on representative soil microbial strains using bensulfuron at 50 mg l^?1 showed some inhibition of three of the 17 bacterial strains and strong inhibition of almost all the 12 fungal strains; cinosulfuron had had no effect on any of these strains in the previous study. It is concluded that, compared with cinosulfuron, bensulfuron is potentially more toxic on soil heterotrophic microorganisms, but only at very high concentrations that are nearly impossible to reach with the usual agricultural use of the herbicides. However, autotrophic nitrifiers were more sensitive to both sulfonylureas than the other microorganisms.