Iranian Journal of

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Backgrounds and Objectives : Vegetables are one of the most important components of daily food. Contamination of vegetables with heavy metals might ends to accumulate in the body, there for in this study the level of lead, chromium, cadmium, arsenic and zinc in cultural vegetables of shahroud suburb were measured in 1387.
Materials and Methods : In this cross-sectional descriptive study, 150 vegetable samples through 3 months, 50 for each month, were randomly harvested. Atomic absorption instrument was used to determine the amount of mentioned heavy metals after sample preparation, SPSS whit 0.05 was used for statistically data analyzing.
Results : For vegetables the average value of Pb, Cr and Cd in different vegetables were different from each other and P value was less than<0.001. There are no significant amounts of Arsenic concentration. The value of these metals with 95% acceptable level was in the range of satisfaction. Arsenic didn&apost have that much of error of its contamination
Conclusion : Except Zn and As other metals like Cr, Cd and Pb were above the standard zone by FAO&WHO. The wastewaters of urban and industrial facilities are the main reason for this problem.The best suggestion is using pure water for this purpose.

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Background & Objectives: The aim of the study was to design and implement integrated solid wastes management pattern in Shahroud industrial area, to evaluate the results, and to determine possible performance problems. Materials & Methods: This cross - sectional study was carried out for 4 years in Shahroud industrial area and the implementation process included: 1. qualitative and quantitative analysis of all solid wastes generated in the area, 2. determining the current state of solid waste management in the area and identifying programs conducted, 3. designing and implementation of integrated management pattern including design and implementation of training programs, laws, penalties and incentives, and illustrating and implementing programs for all factories, and 4. monitoring the implementation process and determining the results. Results: Annually, 1,728 tons of solid waste is generated in the area including 1603 tons of industrial waste and 125 tons of municipal wastes. By implementing this pattern, two separated systems of collection and recycling of domestic and industrial waste were launched in this area. Moreover, consistent with the goals, the amount of solid waste generated and disposed in 2011 was 51.5 and 28.6 kg per 100 million Rials production respectively. In addition, 42 and 40% of the industrial waste and paper were recycled. Conclusion: Results showed that implementation of this pattern, i.e. running source separation, training programs, capacity building, providing technical services, completing chain of industries and strengthening the cooperation between industrial estate management and industrial units could greatly reduce the waste management problems.

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Background and Objectives: Phenol is a toxic and persistent substance in the environment. The aim of this study was to evaluate the performance of silica aerogel synthesized using sodium silicate in the adsorption of phenol from aqueous solutions.

Material and Method: Silica aerogel was prepared by Sol-Gel process. The influence of effective variables such contact time, initial pH of the solution, adsorbent dose, and initial phenol concentration on the adsorption efficiency was investigated. The characterization of prepared silica aerogel and confirmation of phenol adsorption was determined through SEM, XRD analysis and NMR, FTIR spectra respectively. The adsorption data was evaluated via Langmuir and Freundlich isotherms and pseudo-first and pseudo-second-order kinetics.

Results: This research found that the phenol adsorption efficiency increased by increasing pH from 3 to 11, so that after 60 min, the absorption efficiency at the 100 mg/L initial phenol concentration and 0.5 g adsorbent obtained 84 and 96.4 % at pH 3 and 11, respectively. The SEM image and XRD patternof synthesized silica aerogel confirmed the creation of porous and amorphous structure. After the phenol absorption, the NMR and FTIR spectra of silica aerogel, confirmed the creation of new bands because of phenol molecule at the adsorbent structure. The absorption of phenol was compatible with Freundlich isotherm and pseudo-second-order kinetic. The maximum absorption capacity (q_m) obtained was 47.39 mg/g.

Conclusion: Silica aerogel as an adsorbent, due to special characteristics in the structure and usage, can be a promising treatment process for adsorption of toxic and persistent substances.