Production and characterization of mixed matrix membranes based on metal-organic frameworks

Face à la demande mondiale de techniques de séparation des gaz efficaces ayant un impact minimal sur l'environnement, les technologies de séparation des gaz par membrane ont trouvé leur place sur le marché commercial de la séparation des gaz en tant qu'alternatives peu coûteuses et respectueuses de l'environnement. Le cœur d'une technologie de séparation des gaz par membrane est la membrane elle-même, et une sélection judicieuse de son matériau garantit la haute performance de la membrane pour l'application visée. L'un des matériaux les plus étudiés pour les membranes de séparation des gaz est le polymère. Cependant, comme les membranes polymères pures présentent un comportement compétitif entre perméabilité et sélectivité, les membranes à matrice mixte (MMM) sont apparues comme des candidats prometteurs. Les membranes à matrice mixte combinent une facilité de traitement supérieure, un faible coût et une perméabilité modérée des polymères avec une sélectivité élevée des charges. Le défi le plus important pour obtenir une MMM de haute performance est d'avoir une interface sans défaut entre le polymère et la charge pour éviter les perméabilités non sélectives. Cette thèse a étudié les membranes à matrice mixte de polyimide 6FDA-ODA basées sur différents réseaux organométalliques (MOF), comme un nouveau type de matériaux poreux avec de grandes surfaces spécifiques, des tailles de pores ajustables et des propriétés contrôlables pour des applications de séparation de gaz CO₂/CH₄ et CO₂/N₂. L'utilisation de différentes stratégies efficaces dans les techniques de fabrication des MMM et l'amélioration de la qualité de l'interface charge-polymère ont permis d'améliorer les propriétés des MMM et les performances de séparation des gaz, comme le montrent les mesures de perméation des gaz simples et mixtes, ainsi que les résultats des analyses chimiques, thermiques et mécaniques. Dans l'ensemble, les résultats obtenus ouvrent la voie à un développement plus poussé des membranes polymères pour la séparation des gaz.As the global demands for efficient gas separation techniques with minimum impact on the environment have been intensively raised, membrane gas separation technologies found their place in the commercial gas separation market as low-cost and environmentally friendly alternatives. The heart of a membrane gas separation technology is the membrane itself, and a wise selection of its material guarantees the membrane's high performance for the target application. One of the vastly studied materials for gas separation membranes is polymer. However, since neat polymeric membranes show a competitive behavior between permeability and selectivity, mixed matrix membranes (MMM) have emerged as promising candidates. Mixed matrix membranes combine superior processability, low cost and moderate permeability of the polymers with high selectivity of the fillers. The most significant challenge in obtaining a high-performance MMM is to have a defect-free interface between the polymer and the filler to avoid non-selective permeabilities. This thesis studied mixed matrix membranes of 6FDA-ODA polyimide based on various metal-organic frameworks (MOF), as a new type of porous materials with large specific surface areas, adjustable pore size, shape and dimensions, and controllable properties, for CO₂/CH₄ and CO₂/N₂ gas separation applications. Using different effective strategies in MMM fabrication techniques and improving the quality of the filler-polymer interface resulted in improved MMM properties and gas separation performance well supported by single and mixed gas permeation measurements, as well as chemical, thermal and mechanical analyses. Overall, the results obtained open the door for further development of polymer membranes for gas separation

Adsorption of copper, lead and cadmium from aqueous solutions by activated carbon prepared from saffron leaves

Background: Industrial development has caused the release of various pollutants including heavy metals into the environment. These toxic compounds are extremely dangerous to living beings and the environment due to their non-biodegradability, severe toxicity, carcinogenicity, the ability to be accumulated in nature and the ability to contaminate groundwater and surface water. The aim of the present research was to provide an appropriate and cost-effective adsorbent to remove heavy metals from aqueous solutions. Methods: The activated carbon was produced from the dried. Batch experiments were performed on real and synthetic samples at room temperature. The effect of pH, adsorbent dose, initial concentration, and contact time were studied, and the adsorption isotherms of heavy metals were determined. The removal efficiency was evaluated on real wastewater. Results: The maximum removal efficiency of heavy metals (copper, cadmium and lead) by activated carbon adsorbent prepared from saffron leaves was obtained in pH 7. The optimum amount of adsorbent was 0.6 g, and the optimum contact times were 45 min for copper and cadmium ions and 90 min for lead ion, respectively. In these optimum conditions the removal efficiencies were 76.36%, 91.25% and 97.5%, respectively. The removal efficiencies of heavy metals from actual samples (copper industry and the battery industry) in the optimum conditions were 82.25%, 69.95% and 91.23%, respectively. The results obtained showed the highest correlation with Langmuir isotherm model. Conclusion: Based on the results obtained, the activated carbon produced from saffron leaves has a good capability in removal of the metal ions from the aqueous solutions. Considering the availability of saffron leaves in Khorasan, its cost-effectiveness, and high uptake capacity, it can be applied as a proper absorbent to remove the heavy metals from industrial wastewater. Keywords: Adsorption, Heavy metal, Activated carbon, Saffron leaves Citation: Dowlatshahi S, Haratinezhad Torbati AR, Loloei M. Adsorption of copper, lead and cadmium from aqueous solutions by activated carbon prepared from saffron leaves. Environmental Health Engineering and Management Journal 2014; 1(1): 37–44

Cost analysis of the education of students in School of Public Health, Kerman University of Medical Sciences, Iran, using activity-based costing model

Background & Objective: Quantifying real costs in total and per student is one of the key objectives of budgeting in long-term plans for higher education sector; without any doubt, this will improve the performance of universities. However, the evidences and experiences in this regard are very limited within Iran. The purpose of this study was to estimate and analyze all costs of a school (as a model) compatible with activity-based costing in the logics of operating budgeting. Methods: Having reviewed all available relevant documents of School of Public Health, Kerman University of Medical Sciences in one academic year (2010-11), real costs were extracted and categorized. In the same time, all available facilities (classes, laboratories, library, computer rooms, and common rooms), human resources, students, and infrastructures of the school were surveyed. The cost data were grouped into five sections: training costs, research costs, administrative costs, current supportive costs, and maintenance/development costs. Results: The total cost of School of Public Health was 24, 726 million Iranian Rial (IRR) consisted of 18,850 IRR for teaching costs, 1,894 IRR for research costs, 2,519 IRR for administrative costs and 1,463 IRR for maintenance and current costs. The total per student cost was 31.11 IRR. The total per postgraduate student cost was 2.5 times more than of undergraduate students. Conclusion: A main part of the costs, particularly salaries, is out of hand of direct managers of the school. These costs are usually hidden, and are not presented in costs at the school level. It seems that fixed salary of academic staff inflated human costs, while it is suggested that with a better educational management, the system could increase their responsibilities, and improve their productivities. Our computation, as a model, may help medical universities around the country to create a clear picture of their costs in line with the rules of operating budgeting. Keywords Cost per student educational costs operating budget economics of education educational plannin

Study of the coagulation process in wastewater treatment of dairy industries

Aims: In this study, the effect of the coagulation process on treatment of simulated dairy wastewater (SDW) was investigated using the mineral and organic coagulants. Materials and Methods: Different types of coagulants such as inorganic (Alum and ferrous sulphate) and polymeric coagulants (polyacrylamide [PAA] and polyferric sulphate [PFS]) were investigated. Inorganic coagulants dosages were varied from 100 to 1000 mg/L and the polymers dosage was 20 mg/L. Turbidity, chemical oxygen demand (COD), electrical conductivity (EC) and chloride of samples were investigated in optimum pH. Results: Both two coagulants had an optimum dose and pH of 1000 mg/L and 5 respectively. According to the findings, Alum with 95% turbidity removal and 68% COD removal had more high efficiency than ferrous sulphate (95% and 62% efficiency for turbidity and COD removal respectively). When Alum via PFS and PAA as a coagulants aid were used, 82% decrease in COD was obtained using low dose of Alum (100 mg/L). Conclusion: In studied dairy wastewater, Alum was more effective than ferrous sulphate. Addition of 20 mg/L of both two coagulants aid (PFS and PAA) effectively reduced the use of Alum and it was effective in COD removal

Investigation of Fe3O4 Nano‌particles Modified with Orange Peel Efficiency in Removal of Lead and Copper ions from Aqueous Environments

Introduction: Heavy metals with their entry into the food chain and water resources are considered as a serious threat to human health. This study aimed to survey Fe3O4 nano‌particles modified with orange peel efficiency in removal of lead and copper ions from aqueous environments. Methods: This experimental research was implemented during the year 2012 and Fe3O4 nano‌particles were used as adsorbent which were modified with orange peel. Experiments were implemented under batch process by adsorbent (300 mg/L) with changing effective factors such as contact time (20, 40, 60, 80, 100, 150, 200, 250 minutes), pH (3-12), temperature (20, 30, 40, 50 ° C) and concentration of lead and copper ions (10, 20 mg/L). Kinetic adsorption and thermodynamic parameters were investigated according to the conditions of the theory. Results: The maximum adsorption capacity of lead and copper ions on the adsorbent under optimum condition (contact time = 40 min, pH = 6 and temperature = 50 ° C) was obtained which turned out to be 70.06 and 71.21 mg/g respectively. Adsorption of lead and copper ions was according to pseudo-second-order kinetics and with relation to coefficients equal to 0.91 and 0.99 respectively and being fit with Langmuir adsorption model. Positive values of enthalpy (∆Ho) indicated the endothermic nature of the process and negative values of free energy (∆Go) thus indicating the spontaneity of the process. Conclusion: Adsorption of lead and copper ions on the adsorbent under optimum condition turned out to be 98%. The results showed that Fe3O4 nano‌particles modified with orange peel can be an effective adsorbent for the removal of lead and copper ions from contaminated water resources. Keywords: Copper, Lead, Fe3O4 Nano‌particles, Orange Peel, Adsorptio

Farmers’ Pesticide Using Behaviors: A Case Study on Pistachio Farms in Kerman, Iran

Background: Improper use of pesticides has become a serious in regard to human health in recent years. Overlooking safety regulations, using pesticides creates many problems and health hazards for people. Objectives: This paper aimed to investigate the use of pesticides by pistachio farmers in Kerman, Iran. Materials and Methods: This study was conducted in Chatroud County, Kerman Province, Iran. A total of 278 respondents were enrolled in this cross-sectional study to investigate pattern of pesticide use among pistachio farmers. An ANOVA test and Pearson coefficient correlation were used to compare the score of function in applying pesticide and the correlation between quantitative variables. Results: Most of the farmers were illiterate or low-literate (completed primary school) (82%). About 58%of the interviewees had used at least one item of safety equipment during their work with pesticides. The mean score of practice showed a reverse correlation with working years. (r = 0.37, P < 0.001). There was a significant correlation between poisoning and the role of children in spraying (r = 0.31, P < 0.001). Conclusions: The low level of farmers’ education resulted in the improper use of pesticides. It is necessary to introduce appropriate methods for using pesticides to this group and to train them accordingly

The Role of National Sectors in Food and Nutrition Security: The Experience of the Islamic Republic of Iran

Background: Solving the problem of food and nutrition security requires the integration of various sectors of the society. Determining the role of each sector in promoting people&rsquo;s health has presented intersectoral collaboration and transformed the theory of social health determinant approach into action. In this study, with a new approach, and in regards, the national organizations responsible for food and nutrition security have been classified and the role of each has been identified as functions and responsibilities. Methods: This qualitative study was conducted by studying the documents and programs related to food and nutrition security, as well as semi-structured interviews and focused group discussion with two groups, including experts and executives. To determine the role of organizations, the food supply chain was used. Results: According to the food chain, organizations responsible for food and nutrition security in Iran can be divided into three categories: 1. Responsible governance in the economic, political, social, technological, international, and environmental changes affecting food and nutrition security, 2. Responsible governance in the main process of food and nutrition security 3. Supportive sectors and systems for food and nutrition security. Generally speaking, it appears that the government responsible for the main process of food and nutrition security are made up of institutions responsible for providing adequate food, responsible governance for food safety, and responsible governance in the field of nutrition and body consumption. Conclusion: The findings of this study aimed to explain the expectations and responsibilities of ministries and organizations responsible for food and nutrition security

Accuracy of rapid urease test in diagnosing <i>Helicobacter pylori</i> infection in patients using NSAIDs

<b>Background/Aim:</b> This study aimed to determine the effect of nonsteroidal anti-inflammatory drugs (NSAIDs) on the results of rapid urease test (RUT). <b> Patients and Methods:</b> The study evaluated 210 consecutive patients for the diagnosis of <i>Helicobacter pylori</i> (<i>H. pylori) </i>infection. They were divided into case and control groups based on history of NSAID use (n=70 each). Two biopsy specimens were collected from antrum and corpus of stomach during endoscopy and sent for rapid urease testing and histopathology. Sensitivity, specificity, and accuracy rate of RUT test were compared against histology. <b> Results:</b> The average age was 55.2&#177;12.9 and 43.3&#177;12.1 years in the case and control groups, respectively. Among NSAID users, RUT sensitivity, specificity and accuracy rate were all 100&#x0025;. The sensitivity, specificity and accuracy rate of RUT in patients without history of NSAID use were 97.37, 98.57 and 98.14&#x0025;, respectively. The overall sensitivity, specificity and accuracy rate of RUT were 98.57, 99.29, and 99.04&#x0025;, respectively. <b> Conclusion:</b> Our study shows that sensitivity, specificity and accuracy rate of RUT are not affected by NSAID use. Rapid urease test remains a reliable test for diagnosis of <i>H. pylori</i> in patients on NSAIDs

Adsorption of copper, lead and cadmium from aqueous solutions by activated carbon prepared from saffron leaves

Background: Industrial development has caused the release of various pollutants including heavy metals into the environment. These toxic compounds are extremely dangerous to living beings and the environment due to their non-biodegradability, severe toxicity, carcinogenicity, the ability to be accumulated in nature and the ability to contaminate groundwater and surface water. The aim of the present research was to provide an appropriate and cost-effective adsorbent to remove heavy metals from aqueous solutions. Methods: The activated carbon was produced from the dried. Batch experiments were performed on real and synthetic samples at room temperature. The effect of pH, adsorbent dose, initial concentration, and contact time were studied, and the adsorption isotherms of heavy metals were determined. The removal efficiency was evaluated on real wastewater. Results: The maximum removal efficiency of heavy metals (copper, cadmium and lead) by activated carbon adsorbent prepared from saffron leaves was obtained in pH 7. The optimum amount of adsorbent was 0.6 g, and the optimum contact times were 45 min for copper and cadmium ions and 90 min for lead ion, respectively. In these optimum conditions the removal efficiencies were 76.36%, 91.25% and 97.5%, respectively. The removal efficiencies of heavy metals from actual samples (copper industry and the battery industry) in the optimum conditions were 82.25%, 69.95% and 91.23%, respectively. The results obtained showed the highest correlation with Langmuir isotherm model. Conclusion: Based on the results obtained, the activated carbon produced from saffron leaves has a good capability in removal of the metal ions from the aqueous solutions. Considering the availability of saffron leaves in Khorasan, its cost-effectiveness, and high uptake capacity, it can be applied as a proper absorbent to remove the heavy metals from industrial wastewater

The effect of melatonin supplementation on lipid profile and anthropometric indices: A systematic review and meta-analysis of clinical trials

Background: Epidemiological evidence suggests that melatonin has some effects on the serum lipid. However, these results are controversial. The aim of this systematic review and meta-analysis is to examine the effect of melatonin supplement on dyslipidemia and anthropometric indices. Methods: We searched electronic databases including Medline, Embase, Scopus, Web of Science and Cochrane Library up to Des 2018 without any language restriction. To compare the effects of melatonin with placebo, differences in standardized means difference (SMD) with 95 confidence intervals (95 CI) were pooled using random effects model. Results: Twelve trials including 641 participants included in meta-analysis finally. The dose of melatonin was reported at 0.8�30 mg. Comparing with the control group, melatonin may improve low density lipoprotein cholesterol (LDL-C) (�0.31 mmol/L, 95 CI (�0.61, 0.01), P = 0.049, I2 = 42) and triglyceride (TG) level (SMD = �0.45 mmol/L; 95 CI, �0.77, �0.13, P = 0.006, I2 = 47). No significant effect of melatonin on high density lipoprotein cholesterol (HDL-C) and anthropometric indices was found. Conclusions: The results of our systematic review and Meta-analyzes showed that supplementation of melatonin could be effective in improving lipid parameters and should be considered in the prevention of cardiovascular disease, although the effect of this supplement on anthropometric indices needs further investigation. © 2019 Diabetes Indi