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161.
Living or formerly living organisms are being used to obtain information on the quality of the general health status of our environment by bioindication and biomonitoring methods for many decades. Thus, different roads toward this common scientific goal were developed by a lot of different international research groups. Global cooperation in between various scientific teams throughout the world has produced common ideas, scientific definitions, and highly innovative results of this extremely attractive working field. The transdisciplinary approach of different and multifaceted scientific areas—starting from biology, analytical chemistry, via health physics, up to social and economic issues—have surpassed mental barriers of individual scientists, so that “production” of straightforward common results related to the influence of material and immaterial environmental factors to the well-being of organisms and human life has now reached the forefront of international thinking. For the further sustainable development of our common scientific “hobby” of bioindication and biomonitoring, highest personal energy has to be given by us, being teachers to our students and to convince strategically decision makers as politicians to invest (financially) into the development of education and research of this innovative technique. Young people have to be intensively convinced on the “meaning” of our scientific doing, e.g., by extended forms of education. One example of multilingual education of students on a global scale and perspective is given here, which we started about 3 years ago.  相似文献   
162.
Nitrous oxide (N2O) is the third most important greenhouse gas after carbon dioxide and methane, and contributes about 6% to the greenhouse effect. Nitrous oxide is a minor component of the atmosphere, and it is a thousand times less than carbon dioxide (CO2). Nevertheless, it is much more potent than CO2 and methane, owing to its long stay in the atmosphere of approximately 120 yr and the high global warming potential (GWP) of 298 times that of CO2. Although greenhouse gases are natural in the atmosphere, human activities have changed the atmospheric concentrations. Most of the values of emission of nitrous oxide are still obtained by means of emission factors and not actually measured; the lack of real data may result in an underestimation of current emissions. The emission factors used for the calculation of N2O can be obtained from the “Guidelines for the implementation of the national inventory of emissions” of the Intergovernmental Panel on Climate Change, which refer to all nations for the realization of their inventory. This study will present real data, measured in several Italian cement plants with different characteristics. The work also shows a comparison between N2O concentration measured with in situ Fourier transform IR (FTIR) and the reference method EN ISO 21258 based on nondispersive IR (NDIR), in order to investigate the interfering compounds in the measurement with NDIR.
Implications:N2O may arise as an unwanted by-product of nitrogen oxide (NOx) abatement systems, in particular selective noncatalytic reduction (SNCR). Since it is applied in the cement plants, N2O emission from cement industry is evaluated, with both FTIR and NDIR instrument. Several considerations emerged from the results. First of all, the emission from this industrial sector is not negligible, and for that reason N2O concentration should be regulated; another observation is that the reference method based on the NDIR technique is not as selective as FTIR could be.  相似文献   
163.
Acid Mine Drainages (AMDs) from Hane? and Valea Vinului (Romania) closed mines were considered for characterization and treatment using a local zeolitic volcanic tuff, ZVT, (M?cica?, Cluj County, Romania). Water samples were collected from two locations, before and after discharging point in case of Hane? mine, and on three horizons in case of Valea Vinului mine. Physico-chemical (pH, total solid, heavy metal ions concentration) analyses showed that the environment is strongly affected by these AMD discharges even if the mines were closed years ago. Iron, manganese and zinc were the main pollutants identified in Hane? mine AMD, while zinc is the one mainly present in case of Valea Vinului AMD. A batch technique (no stirring) in which the ZVT was put in contact with the AMD sample was proposed as a passive remediation technique. ZVT successfully remove heavy metal ion from AMD. According to heavy metal ion concentrations, removal efficiencies are reaching 100%, varying as follows, Fe2+ > Zn2+ > Mn2+. When the ZVT was compared with two cationic resins (strong, SAR and weak acid, WAR) the following series was depicted, SAR > ZVT > WAR.  相似文献   
164.
The water reservoir of Vargem das Flores, Brazil, has been subject to eutrophication problems. The occurrence of cyanobacterial blooms in this water body has raised concerns regarding the presence of toxic metabolites. In order to understand the factors that promote the proliferation and distribution of cyanobacteria in the reservoir, physicochemical parameters, species composition, and toxicity of the reservoir water column were analyzed at monthly intervals over a 3-year period (2004-2007) using a range of analytical techniques. The results showed that cyanobacteria were absent in the dry period, returning after the onset of stratification. A succession pattern was observed within this group. The Aphanocapsa genus was dominant in the last rainy period of the study (October 2006 to March 2007). However toxicity was only detected when the genera Microcystis and Sphaerocavum were present (October 2005). The principal components analysis showed negative correlation between cyanobacteria and orthophosphate. The change of dominant cyanobacteria along the 3 years of study and the final prevalence of nontoxic genera in the reservoir is an evidence of water quality improvement in response to the management techniques implemented in the reservoir basin.  相似文献   
165.
The aim of this work was the study, by a multiparametric approach, of emissions from a laser printer in an experimental box-chamber, with particular attention to nanoparticles release. The experimental design included number concentration measurements by Fast Mobility Particle Sizer (FMPS) and chemical characterizations (elements) of size segregated samples collected by Nanomoudi cascade impactor. Volatile Organic Compounds (VOCs) were also sampled by charcoal sorbent tubes by personal sampling pumps. Monitoring of ozone, total volatile organic compounds concentrations and of temperature and humidity values inside the experimental box during the printing processes were also performed by automatic analyzers. The performed monitoring allowed to evidence different ways for particles emissions by laser printers, in particular showing that nanoparticles, characterised by high concentrations of Ba, Zn, B, K, Sr and Na, are set free at the beginning of the printing process. This emission seems to be directly ascribable to the use of toner powder, as all these elements are present in it. The emission of larger particles (ca. 100-320 nm) was observed in subsequent phases of the print process, probably due to the condensation of vapours released during the progressive heating of the fuser roller. This contribution was proved by both the FMPS measurements and the cascade impactor results. Also, a low emission of particles in higher size ranges was evidenced, mainly due to paper related particles. A very high concentration of VOCs was detected inside the chamber and the chemical speciation shows that the major contribution is associated to toner components, even if some species are released from other printer components. Although the formation of secondary species by reaction of VOCs with ozone cannot be excluded, these species were present inside the chamber at concentrations lower than the detection limit.  相似文献   
166.
Accurate estimation of total nitrogen loads is essential for evaluating conditions in the aquatic environment. Extrapolation of estimates beyond measured streams will greatly expand our understanding of total nitrogen loading to streams. Recursive partitioning and random forest regression were used to assess 85 geospatial, environmental, and watershed variables across 636 small (<585 km2) watersheds to determine which variables are fundamentally important to the estimation of annual loads of total nitrogen. Initial analysis led to the splitting of watersheds into three groups based on predominant land use (agricultural, developed, and undeveloped). Nitrogen application, agricultural and developed land area, and impervious or developed land in the 100-m stream buffer were commonly extracted variables by both recursive partitioning and random forest regression. A series of multiple linear regression equations utilizing the extracted variables were created and applied to the watersheds. As few as three variables explained as much as 76 % of the variability in total nitrogen loads for watersheds with predominantly agricultural land use. Catchment-scale national maps were generated to visualize the total nitrogen loads and yields across the USA. The estimates provided by these models can inform water managers and help identify areas where more in-depth monitoring may be beneficial.  相似文献   
167.
The addition of nutrients and/or soil bulking agents is used in bioremediation to increase microbial activity in contaminated soils. For this purpose, some studies have assessed the effectiveness of vinasse in the bioremediation of soils contaminated with petroleum waste. The present study was aimed at investigating the clastogenic/aneugenic potential of landfarming soil from a petroleum refinery before and after addition of sugar cane vinasse using the Allium cepa bioassay. Our results show that the addition of sugar cane vinasse to landfarming soil potentiates the clastogenic effects of the latter probably due the release of metals that were previously adsorbed into the organic matter. These metals may have interacted synergistically with petroleum hydrocarbons present in the landfarming soil treated with sugar cane vinasse. We recommend further tests to monitor the effects of sugar cane vinasse on soils contaminated with organic wastes.  相似文献   
168.
Nicotiana tabacum 'Bel W3' is a widely used sensitive bioindicator for ambient ozone, but it is rarely used in tropical countries. Our goal was to determine the suitability of this plant for biomonitoring ozone in the city of S?o Paulo by evaluating the relationships between leaf necroses and ozone under field conditions and measurements of chlorophyll a fluorescence and antioxidants in plants exposed to different concentrations of ozone in closed chambers. While a weak linear relationship between leaf injury and ozone concentrations (R(2)=0.10) was determined in the field, a strong linear relationship was observed in the chamber experiments. Maximum leaf injury was observed in plants submitted to 40 ppb, which coincided with a significant decrease in fluorescence and total ascorbic acid. The relationship between leaf damage observed in the field and ozone was improved when the concentrations were limited to 40 ppb (R(2)=0.28).  相似文献   
169.
The biodegradation of weathered polychlorinated biphenyls (PCBs) (mono and di-chlorinated biphenyls along with PCBs partially ascribed to Aroclor 1242 and 1254) occurring at 1.5-2.5 mg/kg in three different sediments collected from the Porto Marghera contaminated area of Venice Lagoon (Italy) was reported in this study. Strictly anaerobic, slurry microcosms consisting of sediments suspended (at 25% v/v) in a marine salt medium, lagoon water or lagoon water supplemented with NaHCO3 and Na2S were developed and monitored for PCB transformation, sulfate consumption and methane (CH4) production for 6 months. A marked depletion of highly chlorinated biphenyls along with the accumulation of low-chlorinated, often ortho-substituted biphenyls was observed in the biologically active microcosms, where a remarkable consumption of sulfate and/or a significant production of CH4 were also detected. Notably, a more extensive PCB transformation was observed in the microcosms developed with site water (both without or with NaHCO3 plus Na2S), where both the initial concentration of sulfate and sulfate consumption were five fold-higher than in the corresponding microcosms with salt medium. These data indicate that weathered PCBs of the three contaminated sediments of Porto Marghera utilized in this study can undergo reductive dechlorination, probably mediated by indigenous sulfate-reducing and/or methanogenic bacteria.  相似文献   
170.
With reference to the European regulation about the management of End-of-Life Vehicles (ELVs), Directive 2000/53/EC imposes the achievement of a recycling target of 85%, and 95% of total recovery by 2015. Over the last few years many efforts have been made to find solutions to properly manage the waste coming from ELVs with the aim of complying with the targets fixed by the Directive.This paper focuses on the economical evaluation of a treatment process, that includes physical (size and density), magnetic and electrical separations, performed on the light fraction of the automobile shredder residue (ASR) with the aim of reducing the amount of waste to dispose of in a landfill and enhancing the recovery of valuable fractions as stated by the EU Directive. The afore mentioned process is able to enhance the recovery of ferrous and non-ferrous metals of an amount equal to about 1% b.w. (by weight) of the ELV weight, and to separate a high energetic-content product suitable for thermal valorization for an amount close to (but not higher than) 10% b.w. of the ELV weight.The results of the economical assessment led to annual operating costs of the treatment ranging from 300,000 €/y to 350,000 €/y. Since the considered plant treats about 13,500 metric tons of ASR per year, this would correspond to an operating cost of approximately 20–25 €/t. Taking into account the amount and the selling price of the scrap iron and of the non magnetic metal recovered by the process, thus leading to a gain of about 30 €/t per ton of light ASR treated, the cost of the recovery process is balanced by the profit from the selling of the recovered metals. On the other hand, the proposed treatment is able to achieve the fulfillment of the targets stated by Directive 2000/53/EC concerning thermal valorization and reduce the amount of waste generated from ELV shredding to landfill.  相似文献   
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