A rapid removal of xylene vapor from environmental air based on bismuth oxide coupled to heterogeneous graphene/graphene oxide by UV photo-catalectic degradation-adsorption procedure

A simple and fast method based on bismuth oxide nanoparticles coupled to heterogeneous graphene/graphene oxide (BONPs-NG/NGO) was used for the rapid removal of xylene vapor from environmental air by UV photo-catalectic degradation-adsorption procedure (UV-PCDA). By dynamic system, the xylene vapor in pure air was generated in the chamber and flowed to BONPs-NG/NGO sorbent inside in quartz glass tube with UV lamp radiation (QGT-UV) at optimized conditions. In the present of BONPs and UV irradiation, xylene and intermediates (o-xylene, p-xylene, m-xylene) were semi degradated to main fragments by radicals and adsorbed on the surface of NG/NGO (200 mg). After degradation, the main fragments of xylene determined with gas chromatography (GC-MS). Based on the results, the removal efficiency of xylene based on BONPs and BONPs-NG/NGO were obtained 38.8 and 98.7 , respectively. By static system in presence of UV irradiation, the capacity adsorption of xylene with 200 mg of BONPs-NG/NGO and NG/NGO was obtained 223 mg g-1 and 134.6 mg g-1 in 85 °C for 10 min, respectively. The validation of methodology was obtained by spiking of different concentrations of standard xylene in pure air. © 2020 Elsevier Ltd

Nanographene oxide modified phenyl methanethiol nanomagnetic composite for rapid separation of aluminum in wastewaters, foods, and vegetable samples by microwave dispersive magnetic micro solid-phase extraction

A new method based on graphene oxide modified (4-phenyl) methanethiol nanomagnetic composite (Fe3O4@4-PhMT-GO) was used for extraction and separation of aluminum from wastewater, food, and vegetable samples in aluminum cookware by microwave dispersive magnetic micro solid-phase extraction (MDM-μ-SPE). In optimized conditions, the working range (WR), the linear range (LR), the limit of detection (LOD), and enrichment factor (EF) were obtained 5�5200 μg L�1, 5�1600 μg L�1, 1.5 µg L�1, and 48.8, respectively (RSD = 2.5). By MDM-μ-SPE procedure, the aluminum concentrations in baking rice and spinach with aluminum cookware were obtained 97.43 ± 2.57 mg g�1 and 131.64 ± 5.18 mg g�1, respectively which was analyzed by atom trap flame atomic absorption spectrometer (AT-FAAS). The results showed, the aluminum concentrations in cooked foods with Teflon cookware were less than aluminum cookware. The methodology was validated by standard reference materials (SRM) and inductively coupled plasma mass spectrometry analysis (ICP-MS). © 2021 Elsevier Lt

Prioritizing methods of control and reduce noise pollution in Larestan cement Factory using analytical hierarchy process (AHP)

Introduction: exposure to noise pollution leaves Different effects on human. Goal in this Paper is the prioritizing methods of control and reduce noise pollution in Larestan cement Factory using analytical hierarchy process (AHP). Methods: For screening criteria and methods used in AHP technique, Delphi method was used. After polling of 15 experts, 8 criteria and 9 methods was selected from their consensus. Then, in order to prioritizing methods of reduce and control noise pollution, carried out Paired comparison of the methods and criteria, by experts using Analytical Hierarchy Process. Results: result of paired comparison of criteria show that initial investment cost was the most important criteria with the relative weight of 0.247, satisfaction from using of method, Account for the least important with the relative weight of 0.035. A paired comparison of methods according to the target of selecting control methods show that Personal exposure to noise Control method with the weight of 0.224 .was the first priority, and Insulation of building’s Method with the weight of 0.067 was the last priority. Conclusion: Because of personal exposure to noise control method obtained as the best method of controlling noise pollution in this Factory, ACGIH instruction about the time of noise exposure in the workplace suggested to directors

Fixed bed adsorption of hexavalent chromium onto natural zeolite from air stream

Introduction: Chromium (VI) is a known human carcinogenic agent which is used in numerous industrial processes such as electroplating, welding, textile, cement and steel fabrication. The aim of this study was to determine the effectiveness of natural zeolite on the fixed bed adsorption of Cr (VI) from air stream. . Material and Method: In this experimental study, chromium mists were generated by a nebulizer (3A model, Italy). Performance of natural zeolite in the Cr (VI) adsorption and its influencing factors such as air flow rate (1 and 3 L/min), the initial Cr concentration (0.05, 0.15, 1 and 10 mg/m3) and the bed depth (2.5, 5 and 10 cm) were investigated. . Result: Zeolite adsorption capacity elevated by the increasing of bed depth but decreased with increasing of flow rate and inlet concentration. In order to facilitate the prediction of natural zeolite column performance Yoon-Nelson and Thomas models were used. The results showed that these models have a good agreement with our experimental data. . Conclusion: Due to the extensive use of chromium in various industries and regulatory requirements related to workplace health and safety, Cr emission control in the occupational environment is essential. The adsorption process is one of the controlling measures of chromium emissions. The results indicated that natural zeolite has a high efficiency in Cr (VI) adsorption

The Effects of Antioxidant Vitamins on Proinflammatory Cytokines and Some Biochemical Parameters of Power Plant Workers: A Double-Blind Randomized Controlled Clinical Trial

Some epidemiological studies have suggested that exposure to extremely low-frequency magnetic fields (ELF-MFs) can affect the immune system. This study aimed to investigate the effects of antioxidant vitamin consumption on proinflammatory cytokines and biochemical parameters changes. In this randomized, controlled double-blinded trial study, power plant workers exposed to ELF-MFs were enrolled based on inclusion criteria. Ninety-one eligible subjects were randomly divided into four groups: the first group (400 units of vitamin E/day), second group (1,000 mg of vitamin C/day), third group (400 units of vitamin E and 1,000 mg of vitamin C/day), and control group. The intervention was conducted for 3 months. Proinflammatory cytokines interleukin-1β (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α), and biochemical parameters (fasting blood sugar, total cholesterol, triglyceride, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol HDL-c, total protein, and albumin) were measured among the participants� serums, before and after the intervention. The mean level of IL-6 in all vitamin-receiving groups, the mean level of IL-1β in vitamin C and E&C groups, and the mean level of TNF-α in the vitamin C group, decreased significantly after intervention. The arithmetic means of the effect sizes for IL-1β, IL-6, and TNF-α were 0.71, 0.57, and 0.2, respectively. The level of HDL-c in the vitamin E and vitamin E&C groups and the level of triglyceride in the vitamin C group significantly increased after the intervention. Taking antioxidant vitamins can prevent an increase of proinflammatory cytokines induced by prolonged exposure to ELF-MFs. Bioelectromagnetics. 2021;42:18�26. © 2020 Bioelectromagnetics Society. © 2020 Bioelectromagnetics Societ