9 research outputs found
Removal of the metronidazole from aqueous solution by heterogeneous electro-Fenton process using nano-Fe3O4
Among drugs, antibiotics have a significant place due to their wide consumption in veterinary and human medicine to prevent and treat microbial infections. In spite of low amounts of antibiotics in the aquatic environments, the repeated incidence of antibiotics has been caused bacterial persistence and adverse effects on health human and aquatic life. Current article evaluated the removal of metronidazole (MNZ) via heterogeneous electro-Fenton (EF) process by nano-Fe3O4. The response surface methodology (RSM) on Box-Behnken design was applied for modeling and optimization experimental factors such as pH, applied current, and catalyst load. The efficiency of the EF process was maximum (92.26) under the optimal condition for MNZ removal i.e. 70 mg/L of initial MNZ concentration, pH of 3, 200 mA applied current, 30 min time and 3.2 kWh/m3 of energy consumption. © 2018 The Author
Dataset on the knowledge, attitude, and practices of biomedical waste management among Tehran hospital׳s healthcare personnel
The data of this research was the investigation of knowledge, attitude and practices of biomedical waste management among healthcare staff and performed in some general hospitals in Tehran, Iran. In this descriptive data, 162 participants were chosen according to stratified sampling method and a self-made questionnaire was used for data collection. Also, Kruskal-wallis test, Mann -Whitney U tests and Spearman correlation coefficient were used to analyze the data in R software, version 3.4.4. The weighted mean of data showed that the knowledge level in staff is �Low� and their activity level is �Moderate�. Also, the data of the statistical analysis revealed that there is no significant difference between male and female health care personnel in knowledge, attitude and practices. However, the results of Kruskal-Wallis test showed that there was no significant difference between the views of hospital staff in occupational and educational groups about knowledge and attitude and their relationship with the history of passing the health course, while the difference in practices level was significant (P < 0.0001). Furthermore, the relation between attitude and practices level of participants with different work experience were not significant. © 2018 The Author
Some remarks on Φ-sharp modules
The purpose of this paper is to introduce some new classes of modules which is closely related to the classes of sharp modules, pseudo-Dedekind modules and TV-modules. In this paper we introduce the concepts of Φ-sharp modules, Φ-pseudo-Dedekind modules and Φ-TV-modules. Let R be a commutative ring with identity and set H={M∣M is an R-module and Nil(M) is a divided prime submodule of M}. For an R-module M∈H, set T=(R∖Z(M))∩(R∖Z(R)), T(M)=T−1(M) and P:=(Nil(M):RM). In this case the mapping Φ:T(M)⟶MP given by Φ(x/s)=x/s is an R-module homomorphism. The restriction of Φ to M is also an R-module homomorphism from M in to MP given by Φ(m/1)=m/1 for every m∈M. An R-module M∈H is called a Φ-sharp module if for every nonnil submodules N,L of M and every nonnil ideal I of R with N⊇IL, there exist a nonnil ideal I′⊇I of R and a submodule L′⊇L of M such that N=I′L′. We prove that Many of the properties and characterizations of sharp modules may be extended to Φ-sharp modules, but some can not
Data on modeling of UV/Na2S2O8/FeS2 process in amoxicillin removal using Box-Behnken methodology
Among the pharmaceutical compounds, antibiotics have been paid specific consideration, due to their acute and chronic toxic effects on organisms. Amoxicillin (AMX) is used widely for treatment of bacterial infections. About 80 of amoxicillin excreted unchanged and enters the aquatic environment through different routes including disposal of municipal wastewaters, hospital wastewaters and farm wastewaters. In this study degradation of amoxicillin by UV/Na2S2O8/FeS2 process was evaluated. According to the results, the R-squared and adjusted R-squared were 0.9877 and 0.9828, respectively. The AMX removal efficiency was 93 at optimum conditions. Thus, UV/Na2S2O8/FeS2 process is a useful process for amoxicillin removal. © 2018 The Author
Estimation of methane gas by LandGEM model from Yasuj municipal solid waste landfill, Iran
CH 4 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 m 3 /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. © 2019 The Author
A systematic review and meta-analysis of human biomonitoring studies on exposure to environmental pollutants in Iran
Population exposure to environmental contaminants can be precisely observed through human biomonitoring studies. The present study aimed to systematically review all the biomonitoring studies conducted in Iran on some selected carcinogen environmental pollutants. In this systematic review study, 11 carcinogen agents were selected including arsenic, cadmium, chromium, nickel, lindane, benzene, trichloroethylene (TCE), pentachlorophenol (PCP), radon-222, radium-224, � 226, � 228, and tobacco smoke. The Web of Science, PubMed, and Scopus databases were searched for peer-reviewed articles published in English. After several screening steps, data were extracted from the studies. Meta-analyses (a random-effect model using the DerSimonian-Laired method) were performed only for the biomarkers with more than three eligible articles, including cadmium in blood and breast milk, and arsenic in breast milk. Methodological quality of the studies was assessed using the Newcastle-Ottawa Quality Assessment Scale adapted for cross-sectional studies. Of the 610 articles found in the database search, 30 studies were eligible for qualitative review, and 13 were included in the meta-analysis (cadmium in blood (n = 3), cadmium in breast milk (n = 6), and arsenic in breast milk (n = 4)). The overall pooled average concentrations (95 CI) of cadmium in blood, cadmium in breast milk, and arsenic in breast milk were 0.11 (95 CI: 0.08, 0.14), 5.38 (95 CI: 3.60, 6.96), and 1.42 (95 CI: 1.02, 1.81) µg/L, respectively. These values were compared with the biomarker concentrations in other countries and health-based guideline values. This study showed that there is a need for comprehensive action plans to reduce the exposure of general population to these environmental contaminants. © 202
Heterogeneous electro-Fenton process by Nano-Fe3O4 for catalytic degradation of amoxicillin: Process optimization using response surface methodology
The process of amoxicillin (AMX) degradation was investigated by heterogeneous electro-Fenton without external aeration. Graphite felt was modified by means of carbon black and polytetrafluoroethylene (PTFE) to increase the production of hydrogen peroxide and nano- Fe3O4 was also synthesized by chemical co-precipitation method. After optimization of pH and time variables, Box-Behnken design was applied for analyzing and optimization of the experimental factors such as applied current, amoxicillin concentrations, catalyst load and the distance between electrodes. The characteristics of nano-particles with cubic spherical structure and an average diameter of about 20-30 nm were determined via XRD and FESEM techniques. Modification of cathode led to increasing yield of H2O2 by around 5.2 times. Analysis of variance (ANOVA) revealed that the quadratic model was adequately fitted to the experimental data with R2 (0.9884) and adj-R2 (0.9769). Under optimum conditions, the maximum removal efficiency was obtained to be 98.2. Furthermore, the reusability test of nano-Fe3O4 after several cycles confirmed the high catalytic activities of adsorbent. The findings of present study revealed that heterogeneous electro-Fenton process without external aeration was a proper method for degradation of AMX from aqueous solutions. © 2018 Elsevier Ltd. All rights reserved
Association of short-term exposure to air pollution with mortality in a middle eastern tourist city
This study investigated the association of short-term exposure to PM10, PM2.5, NO2, O3, and CO with daily all-cause, cardiovascular, ischemic heart disease (IHD), cerebrovascular, and respiratory deaths in Mashhad, a tourist megacity in Iran (2014�2018). A distributed-lag-day, nonlinear model (DLNM) and generalized additive model (GAM) based on the quasi-Poisson distribution were used to explore the exposure-lag-day-response associations. The average (± standard deviation) concentrations of PM10, PM2.5, NO2, O3, and CO were 67.1 (± 35.5), 29.6 (± 14.2), 57.3 (± 24.1), 55.9 (± 16.9), and 1907.6 (± 1362.7) μg/m3, respectively. NO2 was associated with IHD mortality in lag-days 0 to 0�7, and lag-day 1. The relative risks (RRs) for a 10 μg/m3 increase in NO2 ranged from 1.01 (95 CI 0.93, 1.11) at lag-day 0 to 1.04 (95 CI 0.94, 1.16) and 1.03 (95 CI 0.93, 1.14) for lag-day 0�1 (cumulative) and lag-day 1 (non-cumulative), respectively. For all-cause mortality, cumulative exposure to PM2.5 for lag-day 0�7 (1.07, 95 CI 1.00, 1.15) and non-cumulative exposure to NO2 at lag-day 6 (1.02, 95 CI 1.00, 1.03) were significant. Exposure to PM10 (per 10 μg/m3) was significantly associated with respiratory mortality at several lag-days. Adjusting for Ramadan did not significantly affect the results. PM10 had significant associations with respiratory mortality of people ' 65 years old, and men for several lag-days. For IHD, NO2 affected older people, and men and women over different lag-days. Results of multi-pollutant models were similar to the single-pollutant model outcomes. In conclusion, NO2 and PM10 had more significant relationships with adverse health outcomes than the other pollutants. © 2020, Springer Nature B.V