Mango performance as affected by the soil application of zeolite and biochar under water salinity stresses

This study was carried out during two consecutive seasons, 2020 and 2021, on 12-year-old mango (Mangifera indica L.). cv. Ewaise grown in region Idku, El Beheira Governorate, Egypt. The trees were planted at 5?×?4 m apart and grafted on “Sokary” root stock to study the influence of zeolite and biochar on growth, yield, and fruit quality of “Ewaise” mango cultivar irrigated by agricultural drainage water. The trees were treated by the following treatments: zeolite or biochar solely at 1, 2, and 3 kg for tree and their different combinations such as 1 kg zeolite?+?1 kg biochar; 1 kg zeolite?+?2 kg biochar; 1 kg zeolite?+?3 kg biochar; 2 kg zeolite?+?1 kg biochar; 2 kg zeolite?+?2 kg biochar; 2 kg zeolite?+?3 kg biochar; 3 kg zeolite?+?1 kg biochar; 3 kg zeolite?+?2 kg biochar; and 3 kg zeolite?+?3 kg biochar as well as control zero soil application. The obtained results showed that the soil application of zeolite or biochar gave a positive effect on improving the soil characteristics which reflects on the tree trunk thickness, shoot length and thickness, number of inflorescences, yield in kg per tree, and fruit quality. The greatest positive effect on the previous mentioned parameters was obtained by the combined application of the soil application of 2 kg zeolite?+?3 kg biochar; 2 kg zeolite?+?2 kg biochar; 3 kg zeolite?+?2 kg biochar; and 3 kg zeolite?+?3 kg biochar over the rest-applied treatments or control in the two seasons.

     

Benzene removal by nano magnetic particles under continuous condition from aqueous solutions

Benzene removal evaluated using Fe304 nano continuous condition. A 44 initial benzene concentration, from aqueous solutions was magnetic particles （NM） in factorial design including NM dose, contact time and pH was investigated in 16 experiments （Taguchi OA design）. The results indicated that all factors were significant and the optimum condition was： pH 8, NM dose of 2000 mg.L-1, benzene concentrations of 100 mg.L-1 and contact time of 14min. The maximum benzene uptake and distribution ratio in the optimum situation were 49.4mg.g-1 and 38.4L.g-1, respectively. The nano particles were shown to capture 98.7% of the benzene in optimum batch condition and 94.5% in continuous condition. The isotherm data proved that the Bmnauer-Emmett-Teller model fit more closely and produced an isotherm constant （b） less than one, indicating favorable adsorption. Regeneration studies verified that the benzene adsorbed by the NM could be easily desorbed by temperature, and thereby, NM can be employed repeatedly in water and wastewater management.     

Introducing roadside hazard severity indicator based on evidential reasoning approach

Safety experts have, in recent years, been attentive to roadside accident severity and occurrence. Hitherto, to prioritize road segment hazardousness, there have been little efforts to quantify a well defined indicator. In this regard, the existing indicators are usually very plain and the overall configuration of roadside is rated by experts with an exact number describing its condition. Hence, the uncertainties which come with the subjective judgments cannot be regarded as of any substance. This research contribution therefore presents a procedure to assess the road safety (roadside safety indicator) by means of the evidential reasoning (ER) approach. The betterment of ER as opposed to the available procedures for roadside safety assessment is that the proposed approach makes allowance for the uncertainties which may arise from individual judgments. Additionally, when there is a dearth of evidence concerning factors which affect roadside hazardousness severity to collate several roadside segments, this procedure will offer the benefits of utilizing the maximum/minimum utility function. With the aid of the drawn indicator, organizations and agencies responsible for ensuring road safety can reach more flexible decisions to set in-place uncertain planning and road segments priorities. This indicator can also be utilized as a variable to include roadside conditions in crash severity prediction models. A field case study has also been carried out in an attempt to follow and validate the proposed approach which is based on the run-off accident history for a sample road segments. The crash data confirm the suggested indicator.     

Application of network method as a tool for integrating biodiversity values in Environmental Impact Assessment

Highway construction or expansion projects are among major activities of economic development especially in developing countries. However, road development consistently can lead to major damages to the environment, including habitat fragmentation and ecological instabilities and a considerable threat to fauna and flora. At this point, Environmental Impact Assessment (EIA) in road developments is needed to address and evaluate the ecological issues in decision-making. The object of this study is to strengthen the consideration of ecological issues, i.e., biodiversity in the existing EIA tools. This paper regards a network method as a means to make informed planning decisions by the lessons from a case study. The results indicate that network method is well suited to be applied in ecological impacts assessment. However, some limitations such as complexity and time consumed make casual networks unpopular. Also, impact of traffic noise on acoustic communication (wildlife and human) was performed. It has been shown that sound level for human is much higher than admissible standards. Finally, the study expresses some mitigation measures to improve the acquisition for environmental impact assessment process.     

A review of recent developments in the application of machine learning in solar thermal collector modelling

Environmental Science and Pollution Research - Over the past few decades, the popularity of solar thermal collectors has increased dramatically because of many significant advantages like being a...     

Health effects associated with long-term occupational exposure of employees of a chlor-alkali plant to mercury

This study aimed to evaluate possible health effects associated with long-term occupational exposure to low levels of mercury vapors. Forty-six subjects exposed to mercury and 65 healthy unexposed employees were studied. The subjects were administered a questionnaire on experienced symptoms and underwent clinical examinations as well as routine biochemical tests. Atmospheric and urinary concentrations of mercury were measured, too. Environmental concentrations of mercury were estimated to be 3.97 ± 6.28 μg/m(3) and urinary concentrations of mercury in exposed and referent groups were 34.30 ± 26.77 and 10.15 ± 3.82 μg/dm(3), respectively. Additionally, symptoms such as somatic fatigue, anorexia, loss of memory, erethism, blurred vision and teeth problems were significantly more common among exposed individuals. These observations indicate that occupational exposure to mercury vapors, even at low levels, is likely to be associated with neurological and psychological symptoms.     

Long-term impact of municipal sewage irrigation on treated soil and black locust trees in a semi-arid suburban area of Iran

The effects of municipal sewage irrigation on the soil and black locust (Robinia pseudoacacia L.) tree were studied. For this purpose, two artificial black locust stands under irrigation of municipal sewage and well water were selected in south of Tehran, Iran. Data were collected using technique of systematic random sampling with 4 replicates in each stand. It was found that the growth of black locust tree, as indicated by diameter at breast height, total height, crown length, average crown diameter, basal area and volume, in sewage irrigation stand was much higher than that of well water irrigation stand (P < 0.01). Plant analysis indicated that concentrations of leaf nutrients (N, P, K, Ca, Mg, Na, Fe, Mn, Cu and Zn) were greater in sewage-irrigated trees, without toxicity to the minerals of tree leaf, than those of well waterirrigated trees, and positively correlated with their respective value in soil. Ni, Cr and Pb were not detected in leaf samples. Application of sewage resulted in a 1.5-fold increase in the concentrations of soil nutrients, Ni, Cr and Pb. Among these minerals only Pb and Ni in some soil samples exceeded the toxicity limit. The increase in pH, electrical conductivity (EC) and organic carbon of soil was also observed in sewage irrigation. Results confirm that besides the use as irrigation water, municipal sewages are also a potential source of plant nutrients. However, significant accumulation of heavy metals such as Pb and Ni in soil needs to be monitored.     

Optimization of carbon dioxide absorption in a continuous bubble column reactor using response surface methodology

Carbon dioxide absorption using amine based solvents is a well-known approach for carbon dioxide removal. Especially with the increasing concerns about greenhouse gas emissions, there is a need for an optimization approach capable of multifactor calibration and prediction of interactions. Since conventional methods based on empirical relations are not efficiently applicable, this study investigates use of Response Surface Methodology as a strong optimization tool. A bubble column reactor was used and the effect of solvent concentration (10.0, 20.0 and 30.0 vol%), flow rate (4.0, 5.0 and 6.0 L min⁻¹), diffuser pore size (0.5, 1.0 and 1.5 mm) and temperature (20.0, 25.0 and 30.0°C) on the absorption capacity and also overall mass transfer coefficient was evaluated. The optimization results for maintaining maximum capacity and overall mass transfer coefficient revealed that different optimization targets led to different tuned operational factors. Overall mass transfer coefficient decreased to 34.7 min⁻¹ when the maximum capacity was the desired target. High reaction rate along with the highest absorption capacity was set as desirable two factor target in this application. As a result, a third scenario was designed to maximize both mass transfer coefficient and absorption capacity simultaneously. The optimized condition was achieved when a gas flow rate of 5.9 L min⁻¹, MEA solution of 29.6 vol%, diffuser pore size of 0.5 mm and temperature of 20.6°C was adjusted. At this condition, mass transfer coefficient reached a maximum of 38.4 min⁻¹, with a forecasted achievable absorption capacity of 120.5 g CO₂ per kg MEA.     

Optimization and treatment of wastewater of crude oil desalting unit and prediction of scale formation

In this article, one of Iran’s southwest oil fields that produces 3200 barrels per day (bbl/d) of wastewater from oil and gas processing was investigated. Experimental analysis of oil reservoir water and desalting wastewater disposal of crude oil desalting unit was performed. First, water was treated with a reverse osmosis membrane. As a result, the purified water, with lower total dissolved solids (TDS) and pH, was a suitable candidate for injection into the adjacent wells of the crude oil desalting unit. The effectiveness and compatibility of this wastewater to the formation water of the oil field wells were simulated. Finally, we studied and identified the formation, the amount, and the type of mineral scale deposits. These are the most important problems during water injection into the wells. The analysis shows that the refined water from the reverse osmosis (RO) process was a suitable and low-cost economical option for injection in onshore and offshore fields, due to the low amount of salts, the concentration of susceptible ions in scaling formation, and the appropriate pH. This oil field, which is in the second half of life, requires enhanced oil recovery methods (EOR) for the maintenance of pressure and an increase in oil recovery.