CH4 has a high potential for energy production and by utilizing the proper technology, large amounts of energy can be extracted from it. This study aimed to estimate the amounts of methane emissions from the municipal solid waste landfill in Yasuj city using LandGEM software. The LandGEM model which is used for this aim is based on input data of open landfill year, land closure year, methane production rate, potential methane production capacity, and waste acceptance rate. According to the results, methane gas production during the years 2009, 2010, 2011 and 2012 was obtained to be 250, 275, 303, and 330 m3/h respectively. The results also showed that maximum methane production rate occurred during the years 2010-2012 and then reduced with a soft slope from 2012. The method and results of this research can be used for design and execute of methane gas collection systems and also, control of greenhouse gases emission for the landfills.

In this study, individual performance of ultraviolet irradiation (UV), zinc oxide nanoparticles (ZnO) and hydrogen peroxide (H₂O₂) processes, as well as a performance of combined processes of UV/H₂O₂ and UV/H₂O₂/ZnO, were assessed for the removal of humic acid (HA) from aqueous solutions. Various process-related factors, such as the concentration of ZnO (0.2 and 0.5 g/L), the concentration of H₂O₂ (20, 30 and 50 mg/L), UV = 125 W, pH (4, 7 and 10), initial HA concentrations (at wavelength of 254 nm) of 2, 5, 7 and 10 mg/L, and three types of interferences (nitrate, sulphate and chloride) were studied and optimised. The results showed that removal efficiency decreased by increasing the concentration of HA and pH values in all processes, but it increased by increasing the time of exposure and the concentration of H₂O₂. In the combined process of UV/ZnO/H₂O₂, the nanoparticle concentration of 0.2 g/L yielded the highest efficiency, whereas in the other processes, the highest efficiency was observed at nanoparticle concentration of 0.5 g/L. Based on these results, under the optimum conditions (HA = 2 mg/L, H₂O₂ = 50 mg/L, ZnO = 0.2 g/L, pH = 4.0 and contact time of 15 min), UV/ZnO/H₂O₂ process was found as the most efficient combination in removing of HA with an efficiency of 99.99%. Furthermore, the modelling results indicated that the adsorption reaction of HA onto ZnO nanoparticles was very well described by the pseudo-second-order kinetic model (R² > 0.99).

Controlling and maintaining the cleanliness of the working environment in restaurants is crucial. The aim of this study was to determine the level of contamination on food contact surfaces in restaurants. A total of 28 restaurants were surveyed, and 500 samples were taken from food contact surfaces that appeared clean and ready for use. The surfaces evaluated in this research included workers’ hands, tools and equipment, worktops, chopping boards, meat grinders, spoons and forks, plates, and kebab skewers. Each sample was collected using a swab on a designated 10 cm × 10 cm square area of the surface. The samples were then tested using a luminometer device to measure enzyme levels and identify bacterial contamination, helping to maintain health and control contamination. The unit of measurement for this device is RLU (Relative Light Unit). The results showed that the cleanliness of contact surfaces varied as follows: workers’ hands (46.43%), worktops (53.57%), kebab skewers (89.29%), plates (92.86%), meat grinders (76%), chopping boards (60.71%), tools and equipment (89.29%), and spoons and forks (96.43%). Regarding foodstuff contamination levels, the chopping board, worktop, and workers’ hands had the highest contamination with average RLU values of 1700.89, 1184.50, and 790.71, respectively. In contrast, plates had the lowest contamination, with an average RLU value of 46.68. Based on these findings, training restaurant staff in personal health, food safety, and regular hygiene practices, along with routine inspections based on guidelines from inspectors, will improve restaurant health standards and help reduce foodborne illnesses.

The existence of risk factors of wastewaters to high organic materials, phenol compound, chlorinated compound and other complex providing a discharge of receptive waters could be serious hazards created for life in the water. In this study activated sludge/trickling filter (AS/TF) two-step integrated with upflow suspended growth denitrification (USGD) processes operation evaluated for inert chemical matter removal to conventional treatment. From the wastewater activated sludge system of Isfahan with trickling filter used to sequentially. The media from polypropylene, 240 m²/m³ specific area, 1.8 m diameter and 6 m height applied to TF tank instal. Half industrial pilot part of this two-step system operated from 90 days with flow minimum equivalent to 3.6 m3/h until reached steady state. From AS/TF effluent used to feed four reactors in batch condition and lab scale. These reactors along with two reactors to glucose substrate and equivalent COD with other reactors performance from 504 h in the aerobic condition and room temperature (23–26°C). Each of which of soluble inert materials,total soluble COD, degradable suspended materials, degradable COD, refractory suspended materials and degradable soluble materials parameters calculated for single activated sludge (SAS), AS/TF and USGD effluent that mg/l reached for SAS 32, 180, 86, 234, 220 and 148 respectively. These parameters calculated for a two-step system 16, 180, 195,359,111 and 164 and the USGD process as 8, 180, 201, 373, 105 and 172 respectively. The calculations showed when AS integrated to TF in compare with when one applies single is capable inert COD removed two times and for USGD removed four times.

Public health is influenced by both diet quality and climate changes. The study evaluated the association of greenhouse gas emissions (GHGE) and cumulative energy demand (CED) from diet of 3,203 adults aged 35 to 70 years who participated in the PERSIAN Dena cohort study, considering various nutritional and anthropometric factors. Binary logistic regression was used to investigate the correlation of dietary GHGE and CED on obesity indices including BMI, waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR). The mean of GHGE, non-renewable CED, BMI, WHR and WHtR were found to be 4.88 ± 2.33 kg CO₂-eq/person, 23.1 ± 10.6 MJ/day, 27.82 ± 5 kg/m², 0.97 ± 0.17 and 0.61 ± 0.13 respectively. There were no differences in these indices between lower and upper median groups of GHGE and CED; however, in the fully adjusted analysis, participants in the upper median group of GHGE had a 44%, 21% and 44% higher risk of overweight/obesity or underweight, high WHR and high WHtR, respectively; Based on CED., also, these risks were 42%, 21% and 40%, respectively. GHGE and CED both showed moderate predictive power (AUC: 0.69, 95% CI: 0.67–0.71, P < 0.001). The result suggests that GHGE and CED can serve as useful indicators for assessing the risk of unhealthy body composition; on other hands, integrating environmental sustainability with nutritional health, can be holistic approach that benefits both individual well-being and the planet.