Optimization and Modeling of Ammonia Removal from Aqueous Solutions by Using Adsorption on Single-walled Carbon Nanotubes

Due to the health effects of ammonia as an environmental pollutant, such as its odor, corrosion, algae phenomenon, etc., a method should be adopted to remove it from wastewater. In this study, removal of ammonia from hypothetical wastewater was investigated using adsorption on SWCNTs. The Design-Expert software was used to design the experiments and optimize the parameters that are effective in the adsorption performance of carbon nanotubes (CNTs), such as contact time, adsorbent dosage, pH, temperature, and ammonia concentration. The results revealed that the maximum adsorption with a performance of 90% was attained at a pH of 9.5. In addition, the adsorption performance was enhanced by increasing adsorption time and adsorbent dosage. Furthermore, increasing the temperature and the adsorbate quantity led to a decrease in the adsorption performance

Snakes and Ladders: A New Method for Increasing of Medical Students Excitement

AbstractIntroduction: With respect to abundance of text books and frequency of topics in medical education, new methods can help instructors and students to achieve better results in learning. In this study we proposed a new method and then analyzed students function and attitudes about the efficacy of that. Material and Method: We designed a Snakes and ladders game that there were many questions in that boxes. The questions were about trunk anatomy and this puzzle gave to the 31 first year medical students. The students divided to four people group randomly. After that a questionnaire were given to them including 7 questions. For analyzing data we used SPSS. ver 19. Results: 10 of the students were female(32/2%) and the others were male(67/8%). The mean age of students were 18/73± 0/78. 67/7% of students said that the quality of our exam were good. 51/6% of them thought very good positive attitude. 64/5% of them believed that our design had a very powerful effect on learning. For designing the puzzle 20/45% of questions were designed 3 degree difficulty, 43/18% of them 2 degree difficulty and 36/36% 1 degree difficulty.Discussion: Using new method can excite the students, create landmarks for remembering memorizing methods and can improve their team work. In medical profession, team working has a major role to management the patients

Preparation, Characterization and Application of Zeolite-based Catalyst for Production of Biodiesel from Waste Cooking Oil

129-133Zeolite-based catalyst was prepared from a fine powder and kaolinite by pelletization method and used to synthesize fatty acid methyl esters (FAME) known as biodiesel from waste cooking oil (WCO) containing high amounts of free fatty acids (FFA). The prepared catalyst was characterized by Thermogravimetric analysis (TG/DTA), X-ray Diffraction (XRD), Fourier Transform Infrared (FTIR) spectroscopy and <span style="mso-bidi-font-family:Mangal;color:black;background:white;font-style: normal">Brunauer-Emmett-Teller&nbsp;(<span style="mso-bidi-font-family:Mangal; color:black;font-style:normal">BET) surface area analysis. The zeolite-based catalyst was employed to simultaneously catalyze the esterification of fatty acids and transesterification of&nbsp;triglycerides present in the waste oil feedstock to biodiesel. The condition for biodiesel synthesis was optimized in terms of reaction temperature (50-85 oC), methanol/ WCO molar ratio (2.6-6.0) and reaction time (2-10 h). Maximum triglyceride conversion of 46 % was achieved at the near optimum conditions. These conditions were defined at reaction temperature of 70 oC, methanol/ WCO molar ratio of 5.1 and reaction time of 6 h. </span

The Relationship between Quality of Work Life, Job Stress, Job Satisfaction and Citizenship Behavior in Oshnaviyeh Hospital’s Staff

Introduction: The Organizational Citizenship Behavior (OCB) is an important variable in the study of organization management. It is partly hard to build relationships and performance within the organization. The purpose of this study was to investigate the relationship between the quality of work life, job stress, job satisfaction, and citizenship behavior in Oshnaviyeh Hospital’s staff. Materials and Methods:To collect data, quality of work life by Walton, hospital job stress, job satisfaction, and citizenship behavior questionnaires were used. To determine the reliability of the questionnaires. To analyze data, Pearson Correlation Test,T test, Regression, Path analysis were used. Results: The results show that there is a significant positive relationship between the quality of work life, job stress, job satisfaction, and citizenship behavior. The quality of work life is the most important variable among the independent variables since it was able to identify approximately 18% of citizen behavior. Conclusion: Because OCB is completely voluntary, behaviors are more influenced by their interactions and organizational procedures. Hence, it  is  fair to organizations to know how to deal with employees' level of organizational citizenship behavior

Removal of 17β-estradiol (E2) from Aqueous Solutions by Adsorption Using Oak Jaft and Tea Waste, Isotherm Investigation, and Adsorption Kinetics

The present study aims to investigate wastewater treatment of hormones by oak jaft and tea waste adsorbents. Various factors were used to evaluate the adsorption process, such as the initial pollutant concentration, adsorbent concentration, contact time, and pH. The results showed that both adsorbents, jaft, and tea waste, can adsorb 17β-estradiol. Maximum adsorption was 82.4% for jaft adsorbent and 81.5% for tea waste at 85 min, 7 g/L of adsorbent dose, and pH = 4.5, respectively. The adsorption equilibrium was performed using Langmuir, Freundlich, and Liu models, based on the results, Freundlich model with R2 values >0.97 demonstrated better agreement with the adsorption experimental data. To obtain information on adsorption velocity, three models of pseudo-first-order, pseudo-second-order, and Elovich were used. The findings revealed that the pseudo-second-order model with R2 > 0.98 is a better fit for the experimental data. Therefore, the jaft adsorbent and tea waste can be used as effective and economical adsorbents for the removal of organic pollutants in wastewater treatment plants

The impact of two insecticides on the pollutant cycle and quality of surface and groundwater resources in the irrigated lands of Yasuj, Iran

The increase in the need for food and agricultural development has led to an increase in the use of insecticides. The use of insecticides leads to air, soil and water pollution. This study investigated the pollutant concentration cycle in the environment by analyzing diazinon and deltamethrin in a river and groundwater sources affected by an agricultural area. The samples were analyzed based on the standard method for insecticides in water using a GC-MS. The results showed that the quality of the surface water affected by the agricultural effluents decreased so that the changes of dissolved oxygen, nitrate, turbidity, TOC, BOD, and COD were 15.2%, 189.6%, 00%, 53%, 176%, and 57.5%, respectively. The concentration of diazinon and deltamethrin in agricultural wastewater was 86 μg/L and 11.62 μg/L. The self-treatment capacity of the river reduced the concentration of diazinon in the distance of 2 km and 15 km by 80.8% and 90.3%, respectively. These conditions were observed for deltamethrin in 74.8% and 96.2%, respectively. Also, the concentration of the two insecticides in water resources has temporal and spatial variation. The difference between the maximum and minimum concentration of diazinon and deltamethrin at different times was 183.5 and 1.73, respectively. The concentration of diazinon and deltamethrin in the downstream groundwater of the studied irrigated area was 0.3–0.7 μg/L, respectively. Although the soil structure and the self-purification capacity of the river caused a significant reduction of insecticides, the remained concentration of these pollutants in underground and surface water resources can still be a health and environmental concern

Impact of Covid-19 pandemic lockdown on the urban litter and clean environment index

Abstract Changing the level of pollution in the urban environment is one of the consequences of Covid-19. Litter are one of the most important urban pollutants affected by the Covid-19 pandemic. In this research, the pollution level of urban areas during the Covid-19 pandemic was investigated by studying the urban environment. To this end, the protocol of observation and counting was used and litter were studied in two groups including common litter and Covid-19 related litter in Yasuj, Iran. The results were interpreted based on the clean environment index (CEI). The time of observation was selected based on the peak of the disease and the decline in the incidence rate. The results showed that on average, at the peak of the disease, the density of the litter was reduced by 19% compared to the low lockdown related to Covid-19. The CEI on average was 4.76 at the peak of the disease that was interpreted in the clean status, while the CEI on average was 5.94 at the low lockdown related to Covid-19 so interpreted in the moderate status. Among urban land uses, recreational areas with a difference of more than 60% showed the greatest impact caused by Covid-19, while in commercial areas this difference was less than 3%. The effect of Covid-19 related litter on the calculated index was 73% in the worst case and 0.8% in the lowest case. Although Covid-19 decreased the number of litter in urban areas, the emergence of Covid-19 lockdown related litter was a cause for concern and led to increasing the CEI

Metabolic Signature of Pluripotent Stem Cells

Objective Pluripotent stem cells (PSCs), with the capacity to self-renew and differentiate into all other cell types, are of benefit in regenerative medicine applications. Tightly controlled gene expression networks and epigenetic factors regulate these properties. In this study, we aim to evaluate the metabolic signature of pluripotency under 2i and R2i culture conditions versus serum condition. Materials and Methods In this experimental study, we investigated bioinformatics analysis of the shotgun proteomics data for cells grown under 2i, R2i, and serum culture conditions. The findings were validated by cell cycle analysis and gene expressions of the cells with flow cytometry and quantitative reverse transcription-polymerase chain reaction (qRT-PCR), respectively. Results Expressions of 163 proteins increased in 2i-grown cells and 181 proteins increased in R2i-grown cells versus serum, which were mostly involved in glycolysis signaling pathway, oxidation-reduction, metabolic processes, amino acid and lipid metabolism. Flow cytometry analysis showed significant accumulation of cells in S phase for 2i (70%) and R2i (61%) grown cells. Conclusion This study showed that under 2i and R2i conditions, glycolysis was highlighted for energy production and used to maintain high levels of glycolytic intermediates to support cell proliferation. Cells grown under 2i and R2i conditions showed rapid cell cycling in comparison with the cells grown under serum conditions

Biplot graph of mean of grain yield and the stability parameter of first principal component of the genotypes and environments.

(Square and oval shapes show grouping obtained from cluster analysis of genotypes and environments based on the first principal component, respectively. Horizontal and vertical lines pass from the mean yield and first principal component points equal to zero, respectively). e1: Kerman (normal) and fourth crop year, e2: Kerman (normal) and second crop year, e3: Kerman (normal) and third crop year, e4: Sirjan (normal) and fourth crop year, e5: Neyriz (normal) and first crop year, e6: Kerman (normal) and first crop year, and e7: Sirjan (salinity) and fourth crop year. (PDF)</p