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Photocatalysts show great potential as compounds for restoring contaminated water and wastewater resources. The study aims to synthesize a composite with high photocatalytic potential under visible light to photodegrade the organic pollutants. Ag/Ag3PO4@ TiO2 were synthesized by doping Ag and Ag3PO4 on TiO2. The composite was characterized using X-ray diffraction analysis (XRD), diffuse reflectance spectroscopy, Field emission scanning electron microscopy, and Energy-dispersive X-ray spectroscopy analyses, and its photodegradation ability was investigated by methylene blue. Utilization of pure TiO2 yielded a removal efficiency that was merely half of the efficiency achieved when using modified particles, owing to the reduction of TiO2 s band gap from 3.2 to 1.94 eV. In addition to its enhanced photocatalytic performance under visible light, the synthesized Ag/Ag3PO4@TiO2 photocatalyst demonstrated remarkable efficiency in removing dyes such as methylene blue from aqueous solutions. The removal efficiency at pH less than 7 in 50 ppm methylene blue solution using 3 g/l photocatalyst over 45 min visible light irradiation was approximately 90 percent. Under sunlight, photocatalytic reactions exhibited an efficiency of over 95 percent within 45 min. It can be concluded that the simultaneous introduction of metallic (Ag) and nonmetallic (PO43−) dopants significantly increases the efficiency of electron–hole recombination suppression in the photocatalyst and also decreases the band gap. [ABSTRACT FROM AUTHOR]

Purpose: This research investigated the effect of different regimes of supplementary LED light on physiological and morphological traits of two cultivars of cut Roses. Research method: In this study, treatments included cultivars (Allstar and Dolcevita) and nine light regimes including (Control, LED night from 5 pm to 7 am, LED day from 7 am to 5 pm, LED night day (24 hours light) and LED dark (24 hours, without sunlight) which were all applied in two intensities of 2000 and 4000 lux. Findings: The results showed that the LED light regime had a positive effect on morphological traits such as the number of buds and mean harvest, length, diameter and fresh weight of flowers. LED day 4000 lux improved bud diameter and mean harvest by 18% and 112% respectively compared with control in Dolcevita cultivar. The light regime also caused a significant improvement in physiological characteristics so that in Allstar cultivar LED day 4000 lux, chlorophyll a, b, total, and carotenoid were increased by 66%, 60%, 63%, and 64% respectively compared with control. The vase life in Allstar cultivar by LED night day 4000 lux intensity and Dolcevita cultivar by LED day 4000 lux were 44.5% and 133.2% higher than the control treatment, respectively. Research limitations: There was no limitation. Originality/Value: The results showed that LED night day with 4000 lux intensity had the best results in vase life in Allstar cultivar and LED day supplementary light with 4000 lux intensity increased the quantity and quality characteristics of roses. [ABSTRACT FROM AUTHOR]

Exposure to cypermethrin is common and can lead to acute and chronic health effects. This study aimed to determine the quantitative inhalation risk ofcypermethrinamong the farmers. This cross-sectional study was conducted in nine areas of Shiraz, Iran. Sampling of the respiratory zone was performed by OSHA PV-2063 method using XAD-2 adsorbent andquestionnaire was used to collect the required demographic characteristics and occupational information. Finally, the inhalation risk assessment for exposure to cypermethrin was performed by the Environmental Protection Agency (EPA) method.The mean time-weighted average (TWA) and hazard quotients (HQ) ranged from 0.21 ± 0.1 to 1.68 ± 0.65 and 0.58 ± 0.11 to 1.68 ± 0.46, respectively. 55.6% and 15.2% of the tree spraying and field spraying of the exposed group had HQ more than 1, respectively. Investigation shows that there is no significant relationship between demographic characteristics and HQ values (except height). Exposure frequency (EF), TWA and exposure hour per day had the strongest relationship with HQ.This study showed that the kind of spraying is effective in the amount of risk exposure. The most focus to reduce the health effects associated with inhalation exposure to cypermethrin should be on lowering TWA and exposure hour per day.Due to the high risk of exposure in farmers, it is necessary to identify other effective factors by conducting further studies and presenting their related practical plans. [ABSTRACT FROM AUTHOR]

Mass and energy balance analysis is one of the classical methods of modeling applied in the flash furnace smelting process. This method is an efficient method for degrading the theoretical parameters of silica flux and air required for oxidation processes. In this study, the reaction shaft of the Sarcheshmeh flash smelting furnace has been modeled using the mass and energy balance method. A modeling code has been developed to calculate the oxygen content required for oxidation processes and the silica flux for slagging. Different parameters are effective in the working conditions of the flash smelting furnace. In this research, the effect of concentrate mineralogical analysis, oxygen enrichment, flue dust share, and the amount of natural gas was investigated. The modeling results show that by increasing chalcocite in the feed mixture, the average temperature in the reaction shaft will decrease. Increasing the oxygen enrichment increases the temperature and reduces the amount of off-gases that leave the furnace. The calculation can be repeated via modeling from different modes until improved furnace conditions are achieved and smelting operation is controlled. [ABSTRACT FROM AUTHOR]

In this study, the absorption of BaP in gas phase and biodegradation in liquid phase were examined in a bioscrubber. Important operational parameters including, input concentration (mg/m3), output concentration (mg/m3), pollutant load (g/m3.h), removal efficiency (%), removal capacity (g/m3.h) and biomass value (g/l) were examined. The results of the study showed that the BaP degrading strain performed better degradation by increasing the organic phase concentration and detention time. The results showed that the highest efficiency and removal capacity of bioscrubber occurred at 30% organic phase concentration. Furthermore, by increasing the organic phase concentration, the removal efficiency and capacity of the bioscrubber increased. The results of the study also showed that the removal efficiency of bioscrubber increased by increasing the organic phase concentration from 0%–10%, by increasing the concentration of 10%–20% is gradually increased, and by increasing the organic phase percentage to 30%, the efficiency increased sharply. The results indicated that TPPB can have an acceptable efficacy in removing BaP, which increases by increasing the organic phase concentration leading to more BaP removal. [ABSTRACT FROM AUTHOR]

Benzo[a]pyrene (BaP) is found as an important contaminant in water, air and soil. It can be eliminated through biological removal. The present systematic review aimed to identify the most efficient method for biological removal of BaP from aquatic environments. This systematic review was conducted in 2019, using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) Checklist to investigate the biological removal of BaP from aquatic environments. After searching the databases, 270 studies were found. After the screening stages, 43 studies were reviewed completely. The factors affecting the removal efficiency of BaP including temperature, pH and duration of the experiment (in days) were studied. All 43 studies had reported the pH of the studied environment to be 7.68 (1.04). Six studies reported the mean (SD) temperature to be 31.17°C (4.26°C), and 38 studies reported the mean duration of the experiment to be 69.55 days (166.90 days). Finally, 40 studies reported BaP removal efficiency (Min: 3.8%, Max: 98%). Studies showed the various roles of bacteria and fungi in BaP biodegradation in microbial communities with different ecosystems; in addition, most bacterial species has an important role in BaP biodegradation. [ABSTRACT FROM AUTHOR]