Toxic Effect of a Pesticide, Diflubenzuron on Freshwater Microinvertebrate (Tetrahymena pyriformis)

Harmful bugs affect food production,directly by the qualitativeor quantitative reduction of the harvests,or indirectly while servinglike vectors of several illnesses of the plants and human[1].Many chemical products are used by human for a long time inthe…     

Pretreated waste landfilling: relation between leachate characteristics and mechanical behaviour

The present paper presents a part of a wider research effort aiming at studying the long-term behaviour of different pre-treated wastes once landfilled; in particular, this paper deals with the analysis of settlements and their correlation with the main leachate biochemical parameters (BOD, COD and pH). The municipal solid waste organic fraction (MSWOF) and bottom ash (BA) from incineration of municipal solid waste (MSW) were considered in the study and used to set up different semi-pilot landfill plants. Particularly, the FT plant contained 90 days aerobically biostabilized MSWOF, the FP plant was filled with 15 days aerobically biostabilized MSWOF and the MX plant with a 30-70% (by weight) mixture of BA and the same MSWOF used in the FP plant. The data obtained showed a faster mechanical and biological stabilization of the FT and MX plants, due to the less biodegradable organic fraction content initially present in the FT plant and to the presence of BA, having a stabilizing effect, in the MX plant. Besides, similar behaviour of FT and MX was observed, and also a strong correlation between the settlement and the biochemical parameters time profiles was identified.     

Organochlorine pesticides in feathers of three raptor species in southern Brazil

Environmental Science and Pollution Research - In this study, we determined the presence of organochlorine pesticides (OCPs) in back feathers from three raptor species, Phalcoboenus chimango,...     

Development and calibration of a model for biohydrogen production from organic waste

Existing models for H₂ production are capable of predicting digester failure caused by a specific disturbance. However, they are based on studies using simple sugars, while it is known that H₂ production and fermentation kinetics vary with the composition and characteristics of the substrate used. Because the behaviour of biological processes may differ significantly when the digesting material is a complex matrix, such as organic waste, the aim of this study was to develop and calibrate a mathematical model for the prediction of hydrogen production on the basis of the results obtained from a laboratory scale experimental study using source-selected organic waste. The calibration was carried out for the most important kinetic parameters in mesophilic anaerobic digestion processes and also served as a sensitivity analysis for the influence of both the specific growth rate (μ_max and the half velocity constant (k_s), both of which are strongly dependant on the substrate used. High values of μ_max led to a shorter lag-time and to an overestimate of the cumulative final H₂ production relative to the experimentally measured production. Additionally, high values of k_s associated with amino acid and sugar fermentation corresponded to a lower rate of substrate consumption and to a greater lag-time for growth of hydrogen-producing microorganisms. In this case, a lower final H₂ production was predicted than that which was experimentally observed. Because the model development and calibration provided useful information concerning the role of the kinetic constants in the analysis of a fermentative H₂ production process from organic wastes, they may also represent a good foundation for the analysis of fermentative H₂ production from organic waste for pilot and full-scale applications.     

南京城区冬季大气污染特征

为探究南京城区冬季主要大气污染物浓度变化规律,运用南京市空气自动监测站的φ(CO)、φ(O₃)、φ(NO₂)、φ(SO₂)、ρ(PM_2.5)和ρ(PM₁₀)逐时资料,结合同期气象数据,分析了2014年冬季(2014年12月—2015年2月)南京城区大气污染浓度水平和变化特征,探讨2015年春节期间在实施减排措施下气象条件对空气质量的影响.结果表明:① 观测期φ(CO)日均值和φ(O₃)小时均值未超过GB 3095—2012《环境空气质量标准》二级标准限值;ρ(PM_2.5)、ρ(PM₁₀)、φ(NO₂)、φ(SO₂)日均值分别超标44%、38%、34%、2%;ρ(PM_2.5)、ρ(PM₁₀)最大日均值分别为231和283 μg/m3,分别是GB 3095—2012二级标准限值的3.1、1.9倍. ② 日变化分析显示,φ(CO)与φ(NO₂)呈早晚双峰型变化,与早晚交通高峰源排放有关;φ(O₃)呈明显的单峰型,在午后出现峰值;φ(SO₂)呈单峰型且夜间浓度低于白天;ρ(PM_2.5)和ρ(PM₁₀)为双峰型变化,峰值出现在10:00和22:00左右. ③ 南京地区污染物周末浓度整体高于工作日,其中周末φ(CO)、φ(NO₂)和ρ(PM_2.5)显著高于工作日,“周末效应”显著. ④ 2015年春节期间,南京实施减排措施后,即使在不利的气象条件下,污染物浓度也未出现明显升高,说明减排措施有效削弱了污染源的排放,是保持南京地区良好空气质量的重要因素.      

Prenatal evaluation of fetal renal function based on serum beta2-microglobulin assessment

The relationship between fetal renal function (FRF) and fetal serum beta₂-microglobulin (B2MG) was investigated by comparing its value in 112 unaffected fetuses with that of 23 fetuses presenting with urinary tract malformations (UTM). Fetal serum level of B2MG was totally unrelated to gestational age; its value increased in cases of severe impairment of FRF but was similar to controls in all mild uropathies (p<0.05). Evaluating serum B2MG could be beneficial in fetuses with severe renal damage, but is of no use in unilateral UTM since only the global FRF is tested and not the function of each single kidney. Copyright © 2001 John Wiley & Sons, Ltd.     

Analysis of polychlorobiphenyls from used transformers for polychlorodibenzofurans

The results of analyses for polychlorodibenzofuran (PCDF) content in two samples of polychlorobiphenyl (PCB) from used electrical transformers are presented and discussed. In neither sample was there evidence for enhanced PCDF concentrations even though one of them had been subjected to overheating while in service.     

Polychlorodibenzo-p-dioxins and dibenzofurans in technical pentachlorophenol - results of a collaborative analytical exercise

Results of analyses of eight samples of technical pentachlorophenol conducted by three different analytical methods are presented and discussed.