57 research outputs found

    Preparation and characterization of TiO2incorporated 13X molecular sieves forphotocatalytic removal of acetaminophen fromaqueous solutions

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    Although stabilizing of nano-particles on porous media is a suitable methods in harness-ing the agglomeration and inactivation of nano-particles, but still release of particles to theenvironment remains the most serious challenges facing toward photocatalysis process.Attachment of nanoparticles through ion exchange may be a promising method to solvingthese defects. In this study TiO2was incorporated into the 13X molecular sieves by addi-tion of the titanyl ion through an ion-exchange of ammonium-titanyl-oxalate as well as thedecomposition of titanyl oxalate salt, which remained on the zeolite through the impreg-nation and calcination process. A part of TiO2on the zeolite was also bound through aTi O Si bond. The investigation of TiO2-HX catalytic potential showed that neutral pH and500 mg/L catalyst were the optimal conditions for acetaminophen removal (1 mg/L) in theUV/TiO2-HX process. The maximum removal efficiency of 95.45% ± 0.8 was attained after75 min contact time. The acetaminophen degradation during the UV/TiO2-HX process wasfollowed a pseudo first order kinetic model with rate constants (Kapp) of 0.8676 h−1. Under theoptimum conditions, maximum synergistic efficiency of 60.07% was acquired. The exper-imental data showed that the UV/TiO2-HX process is effective in acetaminophen removalfrom aqueous solutions

    Protective strategies among patients with cardiovascular diseases against dust phenomenon exposure in Ahvaz city based on the protection motivation theory

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    Background: Dust particles are one of the most important environmental problems that are threatening many countries, and patients with cardiovascular diseases (CVDs) are a vulnerable group in this respect. The present study was conducted to examine the protective strategies among patients with CVDs against exposure to dust phenomenon based on the protection motivation theory (PMT). Methods: This cross-sectional study was performed on 183 patients with CVDs who referred to health care centers in Ahvaz city, Khuzestan province, southwest of Iran. Participants were selected from patients with CVDs recruited for routine national Package of Essential Non-communicable Disease (IRA-PEN) through random cluster sampling. Data were collected using a researcher-made questionnaire based on the PMT. Data were analyzed using descriptive and analytical tests such as Pearson correlation coefficient and multiple linear regressions by SPSS version 22. Results: The mean scores of the constructs of perceived response efficacy (4.06 ± 20.06) and sensitivity (19.89 ± 4.30) were higher than those of other constructs. Correlation coefficient test showed a significant positive correlation between risk behaviors of exposure to dust phenomenon and self-efficacy, response efficacy and protection motivation, but negatively correlated with cost response. Also, self-efficacy variable, type of health insurance, and protection motivation were the predictive indicators of behavior. Conclusion: The constructs of the PMT explained the risk reduction behaviors of exposure to dust phenomenon in patients with CVDs. Therefore, this theory can be used as a framework for designing educational programs to increase the motivation of patients with CVDs to adopt risk reduction behaviors for exposure to dust. Keywords: Dust, Risk reduction behavior, Motivation, Self-efficacy, Ira

    Efficiency of Constructed Wetland Vegetated with Cyperus alternifolius

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    The treatment of municipal wastewater from Yazd city (center of Iran) by constructed wetland vegetated with Cyperus alternifolius was assessed. Two identical wetlands with a total working volume of 60 L and 10 cm sandy layer at the bottom were used. First wetland (W1) was control and had no Cyperus alternifolius plant. Second wetland (W2) had 100 Cyperus alternifolius shrubs with 40 cm height. Influent wastewater was provided from Yazd's septic tanks effluents and after a 4-day retention time in wetlands, reactors effluent was sampled for parameters analysis. Results show that chemical oxygen demand (COD), –N, –N, and –P in W1 were reduced to 72%, 88%, 32%, and 0.8%, and in W2, these parameters were removed in values of 83%, 81%, 47%, and 10%, respectively. In both wetlands, the highest and lowest removal efficiencies were related to COD and phosphorus, respectively. Also, the removed phosphorus can be released to stream when the soil saturated or influent phosphorus decreased and when the plant died. After a 4-day-retention time, the W2 wetland showed a statistically significantly lower COD and –N in comparison with W2 wetland

    Human, Environment and Sustainable Development

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    Quantitative and qualitative analysis of construction and demolition waste in Yazd city, Iran

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    Construction and demolition waste is the major category of municipal solid waste that is important due to high volume and mass produced. Therefore, this study aims to analyze the quantitative and qualitative of construction and demolition waste in Yazd. This descriptive cross-sectional study was conducted on a waste disposal site in Yazd in 2017–2018. sampling of the construction and demolition waste disposal site was performed for 12 months (Jul 2017 to Jul 2018). According to a researcher-made checklist, data on the weight, the density and volume of these wastes were collected. The descriptive statistics tests of data were processed in Excel software. 53,445 t of waste are annually generated in Yazd that the amount of cement and concrete, bricks, tile and ceramic (TC), ferrous metals, non-ferrous metals, glass, plastic, wood, and are approximately 38%, 20%, 14%, 11%, 6%, 5%, 3%, and 3%, respectively. With regards to the high volume of waste generated and a remarkable part of the recyclable waste, urban planners should pay attention to the implementation of waste reduction and recycling programs. Keywords: Construction waste, Demolition waste, Waste compositio

    Determination of Arsenic in Dust fall in the Air of Yazd Zahra Soltanianzadeh, Mohammad Hossein Salmani, Mohammad Hassan Ehrampoush

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    Human can live without food and water for many days but they can not live without breathing Air more than a few minutes. Then, Air Pollution is a Problem that additional must attended. Many countries have developed search work and Programs to Control air pollution. There are a lot of industrial activities that lead to the trace element and particles in the air in Yazd city. This study was descriptive and Cross- Sectional. The amount of dust fall in the Air of Yazd was determined and also the amount of arsenic in dust fall was determined. In this study, The Sampling was done from 30 August 2009 to 10 March 2010 at four 1 month's Periods in Jomhuri bulvard, Homafar Square , Shahid Behesti Square , Seyd GoleSorkh Ave , and Aiatollah kashani Street by Jar method. The amount of Arsenic was determined by graphite furnace atomic absorption. The Maximum mean of Arsenic in dust fall was in the second Period equal to 10.677±3.133 μg/kg and the minimum mean of Arsenic was in the Fourth Period equal to 3.066 ±1.205 μg/kg. The maximum value was related to Jumhori Eslamic Bolvard equal to 15 .086 μg/kg and the minimum value was related to shahid Beheshti square equal to 1.134μg/kg. Discussion: Comparison of means the P-value=.062 for different periods and the P-value=.389 for different station was obtained .These was shown that there is no meaningful difference between the Arsenic value in different periods and station. The maximum value of arsenic was observed in the second period of sampling, which is related to enhancement of traffic in city and decrease of air humidity. In addition, the maximum value was in Jumhori Eslamic Bolvard station that is due to existence of industrial factories of in these areas

    Formulation optimization of functional wheat bread with low glycemic index from technological and nutritional perspective

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    Inclusion of prebiotic compounds as indigestible dietary fiber in wheat bread has grown rapidly considering the increased public awareness about their impact on health. However, through their incorporation, the technological characteristics may adversely be influenced by gluten dilution impacts. This study was done to evaluate the impacts of long chain, native and short chain inulin (L-, N-, and S-type inulin, respectively) at 8%, 10%, 12%, 14%, and 16% w/w as Inulin Reconstituted Wheat Flour (IRWF) with similar gluten: carbohydrate ratio of wheat flour (at 10%, 12.5%, 15%, 17.5%, 20% w/w) on technological and nutritional value of wheat bread. Results indicated that despite no gluten dilution induced by IRWF supplementation, technological characteristics were adversely influenced especially at higher substitution level of L-type-containing formulations which is attributed to their higher water absorption index (WAI). Reversely, the nutritional value was positively influenced in which the lowest hydrolysis index (26.64%); predicted Glycemic Index (51.93%) and fructan loss content (25.42%) were found at L-type inulin-containing IRWF at the highest substitution level (20% w/w). As the nutritional value of wheat bread as staple foodstuff is important, optimizing the bread-making process to decrease all reverse impacts induced by L-inulin-type inclusion seems to be required

    Modeling and Performance of Waste Tires as Media in Fixed Bed Sequence Batch Reactor

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    Introduction: The modeling aims to simulate or optimize a process in physical, chemical or biological environments and the derived model will provide a considerable assistance to generate data and predict unknown condition, in case of sufficient suitability. Unsuitable disposal and elimination of waste tires have polluted the environment and human life areas, it also have caused removal of a huge amount of recyclable materials and energy. Besides, attached growth biological processes of wastewater treatment are faced with very high costs of the beds used in such methods. Thus, this study targeted at the following topics: reuse of waste tires, reduction of the costs associated with preparation of biological wastewater treatment system beds, and increased productivity of refineries.  Materials and Methods: The current experimental study was conducted in pilot scale, in which ability of Fixed Bed Sequence Batch Reactor (FBSBR) and Sequencing Batch Reactor (SBR) was evaluated by synthetic wastewater in diverse loadings. Ultimately, the derived data were analyzed using the statistical software packages SPSS and MS Excel. Results: The maximum removal efficiencies of dissolved chemical oxygen demand for FBSBR and SBR reactors were 98.3 % and 97.9 %, respectively. In addition, Stover-Kincannon model provided a very suitable fitness (R2   > 0.99) for loading the bioreactor FBSBR. Conclusion: According to the results, not only waste tires can be reused, but also these wastes can be employed as a proper biological bed in wastewater refineries to improve their efficiency
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