It has been shown that different nitrogen (N) addition led to various influences on soil microbial activities in forest ecosystems; however, the changes of bacteria were still unclear. In this work, inorganic N (NH₄NO₃) and organic N (urea and glycine) were fertilized with different ratios (5:0, 1:4, 3:2, 2:3, and 1:4) on temperate forest soils, while fungicide (cycloheximide) was simultaneously added on half of each treatment to inhibit fungal activities (leaving only bacteria). After a 3-year field experiment, soil samples were harvested, then microbial enzymatic activities involved in carbon (C), and N and phosphorus (P) cycles were determined. Under laboratory conditions, four purified bacteria which were isolated from sample site had been inoculated in sterilized soils under different N types and enzymatic activities were assayed after 90-day incubation. The results showed that cellulase and polyphenol oxidase activities of non-fungicide-added treatments increased after N addition and greater organic N accelerated the increases. However, these enzymatic activities of fungicide-added treatments were not significantly influenced by N addition and N types. It may be due to the insufficient ability of bacteria to synthesize enough enzymes to decompose complex organic C (such as cellulose and lignin) into available compound, although N-limitation was alleviated. Alkaline phosphatase activities increased after N addition in both non-fungicide-added and fungicide-added treatments, and the acceleration on bacterial alkaline phosphatase activities was even greater. Furthermore, organic N showed at least 2.5 times promotion on bacteria alkaline phosphatase than those of inorganic N, which indicated greater alleviation of bacterial P-limitation after the addition of organic N. All the results indicated that soil bacteria may be seriously limited by soil available C but become the dominant decomposer of the complex P compounds after N addition, particularly greater organic N.

The yeast Saccharomyces cerevisiae, a microorganism with cell walls resistant to many types of treatments, was chosen as a model to study electrochemical disinfection process using dimensionally stable anodes (DSA). DSA electrodes with nominal composition of Ti/RuO₂TiO₂ and Ti/RuO₂TiO₂IrO₂ were evaluated in 0.05 mol L⁻¹ Na₂SO₄ containing yeast. The results showed inactivation about of 100 % of the microorganisms at Ti/RuO₂TiO₂ by applying 20 and 60 mA cm⁻² after 120 min of electrolysis, while a complete inactivation at Ti/RuO₂IrO₂TiO₂ electrode was achieved after 180 min at 60 mA cm⁻². When chloride ions were added in the electrolyte solution, 100 % of the yeast was inactivated at 20 mA cm⁻² after 120 min of electrolysis, independent of the anode used. In the absence of chloride, the energy consumption (EC) was of 34.80 kWh m⁻³, at 20 mA cm⁻² by using Ti/RuO₂TiO₂ anode. Meanwhile, in the presence of chloride, EC was reduced, requiring 30.24 and 30.99 kWh m⁻³ at 20 mA cm⁻², for Ti/RuO₂TiO₂ and Ti/RuO₂IrO₂TiO₂ electrodes, respectively, The best performance for cell lysis was obtained in the presence of chloride with EC of 88.80 kWh m⁻³ (Ti/RuO₂TiO₂) and 91.85 kWh m⁻³ (Ti/RuO₂IrO₂TiO₂) to remove, respectively, 92 and 95 % of density yeast. The results clearly showed that yeast, as a model adopted, was efficiently inactivated and lysed by electrolysis disinfection using DSA-type electrodes.

The degradation of phenol was used as a model reaction to investigate the photocatalytic properties of cerium-doped (0.1 nominal atomic percent) TiO₂ catalysts in the presence and in the absence of oxidants: persulfate (PS) or hydrogen peroxide (HP). Experiments were performed in batch reactors using either artificial light (ultraviolet or visible) or solar exposure during spring–summer seasons in La Plata City (34.90° S, 57.92° W, 15 MASL). The formation of hydroquinone, catechol, and p-benzoquinone was observed in all the experiments. Additionally, for the experiments with PS (with or without catalyst), evidence of the formation of dimers and trimers was found. Total degradation of phenol (250 μM) was achieved with doped material and 7 mM of PS (two doses) after 3 h of solar exposure (H S UV, T = 2.9 ± 0.6 10⁵ J m⁻²).

In a previous study, Env Sci Poll Res:1-7, 2015 showed that polychlorinated biphenyls (PCBs), polychlorinated dibenzo dioxins (PCDDs), and polychlorinated dibenzo furanes (PCDFs) are found in commercially available (nano) particular titanium dioxide as a result of the fabrication. Here, we give a brief perspective and reason the toxicity of these new classes of persistent organic pollutants (POPs) by reviewing also their nanoparticular properties, such as surface-to-volume ratio, photocatalytic activity, polarity shifts, and stealth effect. These insights point towards a new class of POPs and toxicologic effects, which are related to the size but not a result of nanotechnology itself. We pave the way to the understanding of until now unresolved very complex phenomena, such as the indoor exposure, formation, and transformation of POP and sick-building syndrome. This is a fundamental message for nanotoxicology and kinetics and should be taken into account when determining the toxicity of nanomaterials and POPs separately and as a combination.

Nitrogen oxides and smoke are the substantial emissions for the diesel engines. Fuels comprising high-level oxygen content can have low smoke emission due to better oxidation of soot. The objective of the paper is to assess the potential to employ oxygenated fuel, i.e., n-butanol and its blends with the neat diesel from 0 to 30% by volume. The experimental and computational fluid dynamic (CFD) simulation is carried out to estimate the performance, combustion, and exhaust emission characteristics of n-butanol-diesel blends for various injection timings (9°, 12°, 15°, and 18°) using modern twin-cylinder, four-stroke, common rail direct injection (CRDI) engine. Experimental results reveal the increase in brake thermal efficiency (BTE) by ~ 4.5, 6, and 8% for butanol-diesel blends of 10% (Bu10), 20% (Bu20), and 30% (Bu30), respectively, compared to neat diesel (Bu0). Maximum BTE for Bu0 is 38.4%, which is obtained at 12° BTDC; however, for Bu10, Bu20 and Bu30 are 40.19, 40.9, and 41.7%, which are obtained at 15° BTDC, respectively. Higher flame speed of n-butanol-diesel blends burn a large amount of fuel in the premixed phase, which improves the combustion as well as emission characteristics. CFD and experimental results are compared and validated for all fuel blends for in-cylinder pressure and nitrogen oxides (NOₓ), and found to be in good agreement. Both experimental and simulation results witnessed in reduction of smoke opacity, NOₓ, and carbon monoxide emissions with the increasing n-butanol percentage in diesel fuel.

This study aimed to explore the effects of different fertilizers and their combinations on growth and nutrient and Cd uptake of Lolium multiflorum. Compared with control treatment, chemical fertilizer, organic manure, and their conjunctions with biofertilizer increased shoot biomass. Biofertilizers were found to cause significant reductions in shoot biomass of plants grown in organic manure-treated and control soil. Decreased soil-available N and P and shoot N and K concentrations in biofertilizer amendment treatments indicated that plant growth and nutrient absorption might be negatively affected under nutrient deficiency conditions. Elevated shoot biomasses contributed to the highest shoot Cd contents in chemical fertilizer and chemical fertilizer + biofertilizer treatments among all treatments. But the maximum translocation efficiency occurred in biofertilizer + chemical fertilizer + organic manure treatment, followed by organic manure and chemical fertilizer + organic manure treatments. Based on the results, we can conclude that the application of only the biofertilizer Bacillus subtilis should be avoided in nutrient-limited soils. Chemical fertilizer application could benefit the amount of Cd in shoots, and organic manure application and its combinations could result in the higher translocation efficiency.

The current study investigates the hepatoprotective effect of Hyrtios aff. Erectus sponge extract against POPs intoxication on endogenous antioxidant enzymes and lipid peroxidation in mice liver tissue. In the present study, the mice BALB/C were assigned into four groups: group I: received saline subcutaneously for 7 days and served as negative control; group II: received subcutaneously for 7 days, 130.6 mg/100 g/b. w/day POPs mixture(mixture of PCB 28, PCB 52,, PCB 101, PCB 118, PCB 153, PCB 138 and PCB 180, alpha-Hexachlorocyclohexane, beta-Hexachloro-cyclohexane, gamma-hexachlorocyclohexane, Aldrin, O,P′-DDE, Dieldrin, P,p DDE, O,P DDD, Endrin, P,p DDD and P,pDDT were extracted from sediments collected from Lake Mariout), and served as induced group; group III: pretreated with Hyrtios aff. Erectus sponge extract for 7 days, as a protection dose and then treated with POPs as group II and served as protective group; and group IV: received i.p Hyrtios aff. Erectus sponge extract of dose 0.7 mg/100 g b.wt/day for 7 days and served as positive control. After 7 days (experimental period), mice were scarified and the liver was harvested for biochemical estimation. Significant reduction in lipid peroxidation (p < 0.002) was noticed compared to POPs-protected group. The antioxidant biomarkers levels were significantly increase as the hepatic GSH and GST increased by 69.9 and 89.9%, respectively. Such increase was accompanied by a decrease in tyrosine kinase activity by 59.82%, additionally remarkable histopathological changes in liver tissue indicate the protective effect of Hyrtios aff. Erectus sponge extract. The results of this study revealed that the Hyrtios aff. Erectus sponge extract has the potential to diminish the destructive effect of POPs intoxication through enhancement of the endogenous antioxidant status. The hepatoprotective activity of Hyrtios aff. Erectus sponge extract is mediated, by the antioxidant effect of its active constituents. The active constituents of Hyrtios aff. Erectus sponge extract were identified by LC-MS/MS.

Natural pozzolan is an amorphous silicate-based material of volcanic origin. In this work, the natural pozzolan was modified by using 3-aminopropyltriethoxysilane (APTES) as a grafting agent. This material was characterized by pHₚzc, N₂ adsorption/desorption curves, FTIR, TGA/DTG, DRUV, SEM, and elementary analysis. The functionalized materials were used for the removal of Reactive Black 5 (RB-5) and Brilliant Green 1 (BG-1) dyes from aqueous solutions using batch-contact adsorption. The characterization of modified pozzolan by FTIR, TGA/DTG, BET, and DRUV–vis revealed the effectiveness of grafting of amine functional group on pozzolan structure. The kinetic adsorption data were better fitted with general order for both dyes while for equilibrium models were better fitted by the Liu isotherm model. The maximum sorption capacities Q ₘₐₓ (at 50 °C) obtained with the modified pozzolan were 350.6 and 300.9 mg g⁻¹ for BG-1 and RB-5, at pH 9.0 and 2.0, respectively. The thermodynamic parameters show that the removal of dyes was spontaneous and endothermic. The modified material was also tested for the treatment of simulated dye house effluents showing very high efficiency.

The Tibetan Plateau (TP) is home to the largest permafrost bodies at low- and mid-latitudes, yet little is known about the distribution and variation of mercury (Hg) in frozen soil of the permafrost regions. In this study, extensive soil sampling campaigns were carried out in 23 soil pits from 12 plots in a high-altitude permafrost region of the Shule River Basin, northeastern TP. Hg distribution, variation, and their dependences on soil properties were analyzed. The results have revealed that total Hg (THg) concentrations were low ranging from 6.3 to 29.1 ng g⁻¹. A near-surface peak of THg concentrations followed by a continuous decrease were observed on the vertical profiles of most soil pits. Significant positive relationships among THg concentrations, soil organic carbon (SOC) contents, and silty fractions were observed, indicating that SOC content and silty fraction are two dominant factors influencing the spatial distribution of THg. THg concentrations in soils showed a decreasing trend with altitude, which was probably attributed to a lower soil potential to Hg accumulation under the condition of lower SOC contents and silty fractions at high altitudes. Approximately, 130.6 t Hg in soils (0–60 cm) was estimated and a loss of 64.2% of Hg from the highly stable and stable permafrost (H-SP) region via permafrost degradation was expected in the upstream regions of the Shule River Basin, indicating that the large areas of permafrost regions may become an important source of global Hg emission as a result of the ongoing widespread permafrost degradation.

Benzene, toluene, ethylbenzene and xylene (BTEX) form an important group of volatile organic compounds (VOCs) affecting troposphere and posing risk to human health. The article examines the Mažeikiai area in the northern part of Lithuania where one of the largest Central European companies and the only oil refinery in the Baltic region (200,000 barrels/day) are close to the Baltic Sea. The research carried out mainly focuses on the following objectives: quantitative assessment of the amounts of BTEX occurring in the impact zone of the oil refinery and transport; estimation of background BTEX concentrations in the region; establishing the main sources of BTEX in the region researched and evaluation of impact of meteorological parameters on BTEX concentrations in different seasons. The passive measurement method was used for analysing VOCs (benzene (C₆H₆), toluene (C₇H₈), ethylbenzene (C₈H₁₀) and ortho-, meta- para-xylene (C₈H₁₀)). The research was carried out in 2010–2012. Its results showed that the average annual concentration of benzene was below the threshold value of 5 μg/m³. Within the measurement period, the average concentration of benzene fluctuated from 1.2 to 2.4 μg/m³, that of toluene varied from 1.3 to 3.5 μg/m³, that of ethylbenzene varied from 0.3 to 0.7 μg/m³ and that of xylene (calculated as para-, meta- and ortho-xylene) varied from 1.0 to 2.4 μg/m³. Compared to the established BTEX concentration, the actual background BTEX concentration in the urban area is two times higher. The seasonal analysis suggests that the highest values of benzene concentration are observed in the winter season.