124 research outputs found
Health Belief Model and Reasoned Action Theory in Predicting Water Saving Behaviors in Yazd, Iran
Background: People's behaviors and intentions about healthy behaviors depend on their beliefs, values, and knowledge about the issue. Various models of health education are used in deter-mining predictors of different healthy behaviors but their efficacy in cultural behaviors, such as water saving behaviors, are not studied. The study was conducted to explain water saving beha-viors in Yazd, Iran on the basis of Health Belief Model and Reasoned Action Theory. Methods: The cross-sectional study used random cluster sampling to recruit 200 heads of households to collect the data. The survey questionnaire was tested for its content validity and reliability. Analysis of data included descriptive statistics, simple correlation, hierarchical multiple regression. Results: Simple correlations between water saving behaviors and Reasoned Action Theory and Health Belief Model constructs were statistically significant. Health Belief Model and Reasoned Action Theory constructs explained 20.80% and 8.40% of the variances in water saving beha-viors, respectively. Perceived barriers were the strongest Predictor. Additionally, there was a sta-tistically positive correlation between water saving behaviors and intention. Conclusion: In designing interventions aimed at water waste prevention, barriers of water saving behaviors should be addressed first, followed by people's attitude towards water saving. Health Belief Model constructs, with the exception of perceived severity and benefits, is more powerful than is Reasoned Action Theory in predicting water saving behavior and may be used as a framework for educational interventions aimed at improving water saving behaviors
Applying job hazard analysis and William Fine methods on risks identification and assessment of jobs in hot rolling steel, Iran
Background and purpose: Comprehensive evaluation of jobs in industries is a practical and effective method that could identify the jobs and industries with negative effects on the environment. This study identified environmental hazards of hot rolling process and assessing their risks. Materials and methods: An observational study was carried out in which identification of human activity and job’s risks in production hall of Kavir Steel Complex was done according to ISO 14001 approaches (pollutant emissions to air, discharges to water, energy consumption, energy released as heat, wastes, side products, etc) by Job Hazard Analysis method (JHA). Then the risks identified were prioritized and assessed using William Fine method. Results: We identified 205 environmental hazards (in 9 groups) associated with production personnel (n= 81), mechanics and maintenance personnel (n= 44), bed personnel (n= 9), personnel of cleaning services (n= 33), and water plant personnel (n= 38). The highest and lowest rate of risks were due to creation and distribution of wastes (n= 73) and corrosion and depreciation of equipment, (n= 1), respectively. Conclusion: The production personnel were mainly responsible for environmental emissions. The leading causes were stress and anxiety about stoppage of production, payment reduction, and lack of awareness and workers and supervisors on environmental issues. © 2017, Mazandaran University of Medical Sciences. All rights reserved
Efficiency of the Combined Chemical Precipitation -Reduction Process to Remove Dye and Chromium from Industry Wastewater of Home Appliance
Background: Industrial wastewater is one the most important pollutants of environment. This study aimed to evaluate the efficiency of the combined chemical precipitation-reduction process for removal of dye and chromium from wastewater of home appliance factories.
Methods: This experimental study was performed in laboratory scale on wastewater from the dying unit of the home appliance factory. The process used was a combination of the chemical precipitation-reduction process. Combine sampling was done and 214 samples were analyzed. COD, dye, and chromium were measured in samples. MgCl2, Polyaluminium Chloride (PAC), and FeCl3, cationic polymer and bentonite were used for chemical precipitation; and sodium meta bi sulfite was used for chemical reduction. Data were analysed by ANOVA and Tukey tests and by SPSS 16 software.
Results: The results show that PAC had the highest color removal efficiency (90.92%). Also, the highest COD removal was related to the combination of magnesium chloride (1.4 mg/l), poly aluminum chloride (0.6 mg/l), and the coagulant aid cationic polymer (0.4 mg/l) with an efficiency of 89.11%. Moreover, total efficiency of the combined chemical precipitation and reduction process in chromium removal was 94%.
Conclusion: The chemical precipitation- reduction process as a pre-treatment method has high efficiency in removal of COD, dye and chrome from wastewater of home appliance factories
Application of novel Modified Biological Aerated Filter (MBAF) as a promising post-treatment for water reuse: Modification in configuration and backwashing process
Biological Aerated Filter (BAF) reactors due to their plentiful biomass, high shockability, high efficiency, good filtration, availability and lack of need for large land areas, are enjoying from great importance in advanced wastewater treatment. Therefore, in this study, Polystyrene Coated by Sand (PCS) was produced as a novel media and its application in a modified down-flow BAF structure for advanced wastewater treatment was assessed in two steps. In step one, the backwash effluent did not return to the system, while in step two backwash effluent returned to increase the water reuse efficiency. The backwash process was also studied through three methods of Top Backwashing (TB), Bottom Backwashing (BB), as well as Top and Bottom Backwashing Simultaneously (TBBS). The results showed that return of backwash effluent had no significant effect on the BAF effluent quality. In the second step similar to the first one with slight differences, the residual average concentrations of TSS, BOD5, and COD at the effluent were about 2.5, 8.2, and 25.5 mg/L, respectively. Additionally, in step two, the mean volume of disposal sludge/volume of treated water (v(ds)/v(tw)) decreased a large extent to about 0.088. In other words, the water reuse has increased to more than 99.91. The backwash time in methods of TB and BB were 65 and 35 min, respectively; however, it decreased in TBBS methods to 25 min. The concentrations of most effluent parameters in this system are in concordance with the 2012 EPA Agriculture Standards, even for irrigation of Non-processed agricultural crops and livestock water consumption. (C) 2017 Elsevier Ltd. All rights reserved
Removal Efficiency of Electrochemical Process by Iron Oxide Nanoparticles Impregnated on Rod Carbon for Arsenite Anions in a High Ionic Strength Solution
The entry of heavy metals (e.g., arsenite anions) into water sources due to industrial and mining activities is considered a serious problem for the environment. Therefore, arsenite removal from polluted water has attracted the attention of researchers due to its toxic effects on human health. In the present study, the efficiency of the electrochemical (EC) purification of arsenite anions in a high ionic strength solution was investigated using a carbon electrode impregnated with iron oxide nanoparticles (NPs). These NPs were synthesized by the co-precipitation method and immediately impregnated on the carbon rod. Experiments were performed by two electrodes (carbon and carbon impregnated with NP electrode) in a 50 mL EC reactor. The effect of different parameters such as electrical current (0.1, 0.3, 0.5, 0.7, & 0.9 A), EC time (2, 5, 10, 15, and 20 minutes), pH (3, 5, 7, 9, & 11), and the initial concentrations of arsenite anion (2, 5, 10, 15 and 20 mg/L) was investigated on the removal efficiency to achieve the highest removal of arsenite anions. Arsenite anions (10 mg/L) were completely removed from the aqueous solution with an ionic strength of 0.141 M at an electrical current of 0.7 A, a pH of 8, and an EC time of 20 minutes. In addition, pH was the most effective parameter in removing arsenite anions from aqueous solution in the EC method. According to the results, EC treatment using an electrode impregnated with iron oxide NPs is highly efficient in removing arsenite anions from the contaminated water
Optimization of photochemical decomposition acetamiprid pesticide from aqueous solutions and effluent toxicity assessment by Pseudomonas aeruginosa BCRC using response surface methodology
Contamination of water resources by acetamiprid pesticide is considered one of the main environmental problems. The aim of this study was the optimization of acetamiprid removal from aqueous solutions by TiO2/Fe3O4/SiO2 nanocomposite using the response surface methodology (RSM) with toxicity assessment by Pseudomonas aeruginosa BCRC. To obtain the optimum condition for acetamiprid degradation using RSM and central composite design (CCD). The magnetic TiO2/Fe3O4/SiO2 nanocomposite was synthesized using co-precipitation and sol�gel methods. The surface morphology of the nanocomposite and magnetic properties of the as-synthesized Fe3O4 nanoparticles were characterised by scanning electron microscope and vibrating sample magnetometer, respectively. In this study, toxicity assessment tests have been carried out by determining the activity of dehydrogenase enzyme reducing Resazurin (RR) and colony forming unit (CFU) methods. According to CCD, quadratic optimal model with R2 = 0.99 was used. By analysis of variance, the most effective values of each factor were determined in each experiment. According to the results, the most optimal conditions for removal efficiency of acetamiprid (pH = 7.5, contact time = 65 min, and dose of nanoparticle 550 mg/L) was obtained at 76.55. Effect concentration (EC50) for RR and CFU test were 1.950 and 2.050 mg/L, respectively. Based on the results obtained from the model, predicted response values showed high congruence with actual response values. And, the model was suitable for the experiment�s design conditions. © 2017, The Author(s)
Optimization of photochemical decomposition acetamiprid pesticide from aqueous solutions and effluent toxicity assessment by Pseudomonas aeruginosa BCRC using response surface methodology
Contamination of water resources by acetamiprid pesticide is considered one of the main environmental problems. The aim of this study was the optimization of acetamiprid removal from aqueous solutions by TiO2/Fe3O4/SiO2 nanocomposite using the response surface methodology (RSM) with toxicity assessment by Pseudomonas aeruginosa BCRC. To obtain the optimum condition for acetamiprid degradation using RSM and central composite design (CCD). The magnetic TiO2/Fe3O4/SiO2 nanocomposite was synthesized using co-precipitation and sol�gel methods. The surface morphology of the nanocomposite and magnetic properties of the as-synthesized Fe3O4 nanoparticles were characterised by scanning electron microscope and vibrating sample magnetometer, respectively. In this study, toxicity assessment tests have been carried out by determining the activity of dehydrogenase enzyme reducing Resazurin (RR) and colony forming unit (CFU) methods. According to CCD, quadratic optimal model with R2 = 0.99 was used. By analysis of variance, the most effective values of each factor were determined in each experiment. According to the results, the most optimal conditions for removal efficiency of acetamiprid (pH = 7.5, contact time = 65 min, and dose of nanoparticle 550 mg/L) was obtained at 76.55. Effect concentration (EC50) for RR and CFU test were 1.950 and 2.050 mg/L, respectively. Based on the results obtained from the model, predicted response values showed high congruence with actual response values. And, the model was suitable for the experiment�s design conditions. © 2017, The Author(s)
Prevalence of Sleep Disturbance and Neuropsychological Learning Disabilities in Preschool Children in Isfahan City
Introduction: The prevalence of sleep disorders is different in international studies. Sleep disorders with the increasing prevalence among children is common. Cognitive problems are the most serious complication of sleep disorders in children. The present study, the prevalence of sleep problems and neuropsychological learning disabilities were evaluated on pre-school children (4-6 years old) in Isfahan in the year of (1393-1394).
Methods: This descriptive study was conducted on 350 pre-school children in 1393-1394. They have been selected for cluster sampling method. The sleep disturbances scale questionnaire for children (SDSC) and Conners neuropsychological questionnaire were given to the mothers of pre-school children.
Results: The results showed 144 (41.14%) pre-school children were prone to sleep disturbances, out of 280 pre-school children, 92 people (32.85%) had neuropsychological learning disabilities, 31 children, disorders of initiating and maintaining sleep (8.85%), 15 children, sleep disordered breathing (4.28%), 53 children, excessive sleepiness disorder (15.14%), 74 children, sleep wake disorders (21.14%), 32 children, 32 children, arousal disorder (9.14%), 43 children, sleep hyperhidrosis (12.28%), 62 children, attention problems (22.14%), 1 children, impaired sensory function (0.7%), 4 children, language dysfunction (1.42%), 7 children, general learning and memory impairment (2.5%), 14 children, executive dysfunction (6.42%).
Conclusion: The prevalence of sleep and attention problems could indicate the importance of sleep and attention problems, furthermore, it could be awareness as regards patterns of the healthy sleep and neuropsychological learning disabilities in order to enhance the awareness of parents and health care providers
Equilibrium And Kinetics Study Of Reactive Red 123 Dye Removal From Aqueous Solution By Adsorption On Eggshell
The aim of this study was to determine the equilibrium and kinetics
adsorption of reactive red 123 dye (RR 123) from aqueous solution with
chicken’s eggshell as an adsorbent. The initial concentrations of
reactive red 123 dye were selected in the range of 25 and 50 mg/L. The
target adsorbent was prepared in laboratory conditions and pulverized
by ASTM standard sieves. Measurement of the adsorbent surface area was
carried out via Brunauer-Emmett-Teller isotherm. The experimental data
were analyzed with Langmuir, Freundlich and Temkin isotherm models. The
results showed that the calcium components were the main constituents
of eggshell (around 95% Ca). The experimental adsorption isotherm was
in good concordance with Langmuir and Freundlich models (R2>0.90)
and based on the Langmuir isotherm the maximum amount of adsorption
(qmax) was 1.26 mg/g. Increase of the eggshell dose and the solution
temperature beyond 45ºC led to decrease of the adsorbed dye per
mass unit of the adsorbent, but increase of the solution pH up to 9 led
to the improvement of dye adsorption. The kinetic studies revealed that
the adsorption of reactive red 123 was rapid and complied with
pseudo-second order kinetic (R2= 0.99), with the kinetic constant of
0.02 g/mg.min
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