The effect of air staging strategies on NOₓ control was investigated on a 210-kW small-scale biomass boiler (SBB) and a 1.4-MW medium-scale biomass boiler (MBB). Considering the de-NOₓ effect, as well as the convenience and economy for future wide use, the structures of the secondary air duct and the fuel feed tube were innovatively designed to solve the problems of the traditional prototype. The preliminary experiment showed that the lowest NOₓ emission was achieved when the air excess (ε) was equal to 2.04. Then, additional operating modes were conducted on the MBB to further optimize the air staging strategies. The optimal air staging strategy of the MBB (the secondary to primary air flow ratio (λ) and the ε were equal to 0.13 and 0.76, respectively) could decrease the NOₓ emission from 338.12 to 148.14 mg/m³. Furthermore, the SO₂ emissions and the lowest NOₓ emission of the SBB and the MBB could meet most emission standards of China and some developed countries. The thermogravimetric analysis (TG) and combustion characteristics of the wood fuel showed that the air staging was a suitable de-NOₓ technology for wood combustion, and the slagging was less likely to occur under the selected condition. Hence, the air staging technology was an effective and low-cost method for the emission reduction of biomass boilers. This study provided a practical basis for future research on the gas emission control of biomass boilers.

In the planning and authorization process of industrial plants or agricultural buildings, it needs to be ensured that odor emissions do not annoy nearby residents in an unacceptable way. Previous studies have shown that odor-hour frequency is an important predictor for odor annoyance. However, odor-hour frequencies can be assessed for day and night separately. The present study relates complaint rates with different odor types and different metrics of frequency calculated via a dispersion model. Binary logistic regression analyses show that odor type and frequency of odor-hours are important predictors for complaints, while type of residential area does not increase the predictive value of the model. The combination of calculated frequency of day time odor-hours and type of odor explains complaint rates best. It is recommended to keep odor emissions as low as possible, especially for highly annoying odor types.

Active pharmaceutical ingredients such as tricyclic antidepressants (TCAs) are contaminants of emerging concern which are commonly detected in wastewater effluent and which can disrupt the behavior of non-target organisms. In aquatic snails, the righting response is a critical behavior that has been shown to be inhibited by exposure to SSRI-type antidepressants. We exposed marine and freshwater snails to three tricyclic antidepressants (clomipramine, amitriptyline, and imipramine) for 1 h and measured righting response time. In the marine mud snail (Ilyanassa obsoleta), all three TCAs significantly increased righting time at concentrations as low as 156 μg/L. Similarly, in the freshwater snail Leptoxis carinata, all three TCAs increased righting time at concentrations as low as 263 μg/L. However, exposure to imipramine from 15.8 to 316 μg/L resulted in significantly faster righting time. Such low-dose stimulation and high-dose inhibition are characteristics of a hormetic response. We discuss the possible physiological mechanism of action of TCAs and other antidepressants on snail behavior, and the occurrence of non-monotonic, hormetic dose responses to human pharmaceuticals in the aquatic environment.

Air pollutants and allergens are the main stimuli that have considerable effects on asthmatic patients’ health. Seamless monitoring of patients’ conditions and the surrounding environment, limiting their exposure to allergens and irritants, and reducing the exacerbation of symptoms can aid patients to deal with asthma better. In this context, ubiquitous healthcare monitoring systems can provide any service to any user everywhere and every time through any device and network. In this regard, this research established a GIS-based outdoor asthma monitoring framework in light of ubiquitous systems. The proposed multifaceted model was designed in three layers: (1) pre-processing, for cleaning and interpolating data, (2) reasoning, for deducing knowledge and extract contextual information from data, and (3) prediction, for estimating the asthmatic conditions of patients ubiquitously. The effectiveness of the proposed model is assessed by applying it on a real dataset that comprised of internal context information including patients’ personal information (age, gender, height, medical history), patients’ locations, and their peak expiratory flow (PEF) values, as well as external context information including air pollutant data (O₃, SO₂, NO₂, CO, PM₁₀), meteorological data (temperature, pressure, humidity), and geographic information related to the city of Tehran, Iran. With more than 92% and 93% accuracies in reasoning and estimation mechanism, respectively, the proposed method showed remarkably effective in asthma monitoring and management.

Biodiesel has been renowned as potential and alternative fuel for years. In order to improve the quality of the conventional fossil fuels, biodiesel, and air pollution from combustion, additives are essential to exploit. In this study, the uses of cerium oxide (CeO₂) nanoparticle additive for B20 fuel in a diesel engine are investigated. The CeO₂ nanoparticles with cetyl-trimethyl ammonium bromide are doped into the B20 fuel by using ultrasonicator. The purpose of the experimental work was adopted to enhance engine combustion and reduce the emissions with an approach of CeO₂ nanoparticle additive. The experiment was conducted on a diesel engine using different propagation of CeO₂ nanoparticle in blended mahua methyl ester fuel such as B20 + CeO₂ 50 ppm, B20 + CeO₂ 100 ppm, and B20 + CeO₂ 150 ppm. The obtained results are compared with the diesel and B20 fuels. The minor changes are obtained in B20 fuel properties due to the addition of CeO₂ nanoparticles. The performance of brake thermal efficiency and combustion of pressure data is observed to be enhanced by the addition of a metal-based additive. The CO, HC, and smoke are decreased for B20 fuel with nanoparticles. The NOₓ is reduced by dosing the CeO₂ due to the oxidation of unburned CeO₂ in the exhaust.

Phosphoric acid production and olive oil production are among the most important economical sectors in Tunisia. However, they generate huge amounts of wastes (phosphogypsum, olive mill waste water, and olive pomace). In a previous study, we used phosphogypsum (PG), in co-composting with organic wastes. Three composts were produced; their PG content was of 0 (AT), 10 (A10), and 30% (A30). In the present study, we focused on their derived compost teas. The physico-chemical characterization of the different compost teas showed that those from A10 and A30 composts presented higher P and Ca contents than that from control one (AT). The microbial characterization using DGGE showed a noticeable microbial diversity in the different compost teas and that the addition of 10% and 30% PG in the compost had different effects on the compost tea microbial diversity. The identification results showed that the addition of 10 and 30% of PG did not affect the presence of PGPR (plant growth-promoting rhizobacteria) and fungal soil antagonists in the compost teas. Two PGPRs were isolated from AT and A30 compost teas, and their effect on the growth of potato plants in vitro was evaluated.

Essential oils (EOs) extracted from leaves (EL) and fruit pericarp (EFP) of Zanthoxylum planispinum var. dintanensis were analyzed for their chemical composition by GC-MS technique and evaluated for their fumigant, contact toxicity and repellency against three stored-product insects, namely Tribolium castaneum, Lasioderma serricorne, and Liposcelis bostrychophila adults. Results of GC-MS analysis manifested that EL and EFP of Z. planispinum var. dintanensis were mainly composed of oxygenated monoterpenes. Major components included linalool, sylvestrene and terpinen-4-ol. The obvious variation observed between two oil samples was that EL contained 2-dodecanone (11.52%) in addition to the above mentioned components, while this constituent was not detected in EFP. Bioassays of insecticidal and repellent activities were performed for EL, EFP as well as some of their individual compounds (linalool, terpinen-4-ol and 2-dodecanone). Testing results indicated that EL, EFP, linalool, terpinen-4-ol and 2-dodecanone exhibited potent insecticidal and repellent activities against the three target insects selected. Among the three individual compounds, 2-dodecanone was significantly toxic to T. castaneum (LD₅₀ = 5.21 μg/adult), L. serricorne (LD₅₀ = 2.54 μg/adult) and L. bostrychophila (LD₅₀ = 23.41 μg/cm²) in contact assays and had beneficial repellent effects on L. serricorne at 2 and 4 h post-exposure. The anti-insect efficacy of Z. planispinum var. dintanensis EO suggests it has potential to be used as botanical insecticide or repellent to control pest damage in warehouses and grain stores.

Nutrients in runoff degrade water quality. The development of schemes to mitigate such degradation requires a characterization of the underlying dynamic processes of nutrient loss. The drinking-water source protection area in the Lake Hongfeng watershed of Guiyang City, the capital of Guizhou Province, China, has been delimited for effective conservation. However, no systematic observations have provided data on nutrient losses from these areas that could support optimal management. We selected one typical watershed in the area. Automatic gauges were installed to record the water levels and calculate runoff rates during 2010 and 2011. A total of 1523 runoff samples were collected at an interval of 3 h during a day; total nitrogen (TN), total phosphorus (TP), and chemical oxygen demand (COD) were tested. The results indicated that surface runoff rates were primarily less than 15 L/s but rapidly increased 1–30 times 15 L/s when it rained. TN, TP, and COD concentrations primarily fluctuated between 0.06 and 18.79 mg/L, between 0.01 and 1.57 mg/L, and between 0.01 and 160 mg/L, respectively. TN and COD concentrations in 98.98% and 52.04% of the runoff samples, respectively, exceeded the upper limit required by the Environmental Quality Standards for Surface Water (EQSSW) in China. Conversely, 94.29% of the runoff samples had lower concentrations than the upper limit of TP concentration. Surface runoff has been seriously polluted by nitrogen and organic pollutants. The occurrence frequency of different runoff rates and TP and COD concentrations showed different distributions, but TN concentrations had a normal distribution. There was a significant relationship between runoff rates and TP concentration and TN, TP, or COD loss. TN, TP, and COD loss primarily occurred on vegetable lands, rice fields, and residential sites. Effectively controlling nitrogen fertilizer that is applied on vegetable lands and paddy fields and managing wastewater and solid waste are urgent. The results reported here will also provide references for many other regions facing similar problems.

Polychlorinated biphenyls (PCBs) represent a large group of recalcitrant environmental pollutants. Up to now, many studies have focused on bioremediation of PCBs by fungal strains; however, the mechanisms of adaptation of these strains towards PCBs remain unknown despite their importance in developing effective bioremediation processes. We studied five species, each consisting of two strains isolated either from PCB-polluted or PCB-unpolluted substrates (control strains). We investigated their responses to PCB contamination by studying their tolerance to PCBs, their ability to reduce these pollutants, and their expression level of Laccase genes. In Thermothelomyces thermophila, Thermothelomyces heterothallica, Thermoascus crustaceus, and Fusarium solani, all the studied strains showed a similar tolerance and PCB degradation regardless of their origin. In Schizophyllum commune, while both strains showed similar resistance to PCBs, i.e., PCBs and their degradation products presented no toxicity for these strains, the rate of PCB degradation of the strain from a PCB-polluted environment was significantly slightly higher. The PCB degradation did not correlate with the expression level of genes encoding Laccases. These results demonstrate that the tolerance and PCB degradation by the fungal strains, which did not involve Laccase genes, required different adaptation systems which seem to be constitutive or rapidly inducible by PCB according to the fungal species.

The article Occurrence and risk assessment of trace metals and metalloids in sediments and benthic invertebrates from Dianshan Lake, China, written by Yan Wu, Yihui Zhou, Yanling Qiu, Da Chen, Zhiliang Zhu, Jianfu Zhao and Åke Bergman