فهرست مطالب seyed mehdi ghasemi

Air pollution is one of the important issues in developing countries, due to increased population and industrialization. In this research, the spatial distribution of ambient air concentration such as CO, NO2, SO2, PM2.5, PM10, O3 and Air quality Index (AQI) in Tehran city in 2015 were evaluated using different deterministic ( inverse distance weighted, local polynomial, global polynomial, radial basis functions) and geostatistical (Kriging, Cokriging) methods. Root Mean Square Error (RMSE) and Mean Error (ME) using cross-evaluation methods were used to control the accuracy of the interpolation. To find the secondary variables in the cokriging method, the Pearson coefficient of each pollutant was calculated with another pollutant. The Kolmogorov-Smirnov test showed that all data followed normal distribution. Also the results indicated that in most cases, geostatistical methods were the best methods to estimate ambient air concentration. Finally, after selecting the best interpolation method, the zoning map of the pollutant was drawn with ArcGIS. The results of 71 methods showed that in most cases, the geostatistical method is better than the deterministic method

Smoking is the largest preventable cause of death in the world, killing nearly 6 million people annually. This article is an investigation of measures implemented laws in the Iran to study the proposed strategy of control and reduce tobacco use based on the monitor, protect, offer, warn, enforce and raise (MPOWER) policy.
All laws approved by the Parliament along with the instructions on tobacco control prepared by the Ministry of Health and Medical Education, Ministry of Industry, Mine and Trade were collected and studied. Moreover, practical steps of Ministry of Health and other organizations were examined in this regard.
Findings: Iranian Parliament after the adoption of the Framework Convention on Tobacco Control (FCTC) acts to create a comprehensive and systematic program for tobacco control legislation as a first step towards comprehensive national tobacco control and combat. In this law and its implementing guidelines and based on the strategy of MPOWER, specific implement is done to monitor tobacco use and prevention policies, protect people from tobacco smoke, offer help to quit tobacco use, warn about the dangers of tobacco, enforce bans on tobacco advertising, promotion and sponsorship and raise taxes on tobacco. However, the full objectives of the legislation have not achieved yet.
According to Iran’s membership in the FCTC and executive producer of tobacco control laws and regulations, necessary infrastructure is ready for a serious fight with tobacco use. In Iran, in comparison with developed countries, there is a huge gap between ratified laws and performing of laws.

Chromium occurs mainly in the oxidation states (III) and (VI), and finds in the wastewater industries such as electroplating, glass, ceramic, leather and tanning, tannery industries. Hexavalent Chromium (VI) is reported as confirmed carcinogen. The aim of this study was to evaluate removal efficiency of chromium (VI) by using Barberry stems powder from aqueous solutions.
This study was done in laboratory scale. The Barberry stems powder prepared in lab conditions and Pulverized using ASTM standard sieves (40-60 mesh). The effects of adsorbent dose (Barberry stems powder), initial concentration of hexavalent chromium, contact time and pH on the removal chromium were investigated. The concentration of chromium (VI) in all samples measured by spectrophotometer at 540 nm. For better understanding of the adsorption process, the experimental data were analyzed with Langmuir and Freundlich isotherm models and pseudo first order and pseudo second order kinetic studies. Finally, the data were analyzed by EXCEL.
The results showed that the removal efficiency of Cr was fixed and 100% in all amounts of adsorbent. By increasing of reaction time, the Cr removal rate increased and by increasing of Cr initial concentration and pH, the removal efficiency decreased. By increasing of pH from 2 to 9, the Cr removal efficiency with 2 mg/L chromium decreased from 100% to 16.4%. Furthermore, the data were well fitted with Langmuir isotherm and pseudo- second -order kinetic.
According to the results, Barberry stems powder is able to absorb the Cr (VI). Removal efficiency of Cr (VI) in pH=2 was at its optimum capacity. The results of this study demonstrated that the Barberry stems powder can be used as an effective and appropriate adsorbent.

Zinc is one of trace elements essential for human but too much zinc can cause eminent health problems especially in drinking water that must be removed. The purpose of this study was to determine the removal zinc from water by natural and modified maize hull.
Material and This stady was non-continuous experiment which was implemented in lab scale conditions by changing effective factors such as pH(2 to 7), contact time(5 to 180 minutes), adsorbent concentration(10 to 150 ppm) and adsorbent dosage(1 to 6 g/l) in 100 ml deionized water. The concentration of zinc was measured by atomic adsorbtion in accordance with standard method and removal percentage of zn deteminated.
Removal rate of zinc increased with increasing the contact time, dose of adsorbent, pH and decreasing by initial concentration of zinc. Efficiency of natural and modified maize hull in the optimum state was 91% and 98% respectively. The kinetic and isotherm was pseudo second order and Langmuir(II) respectively. ANOVA analysis showed that all of the variables in the process have been statistically significant effect (p Conclution: According to the results obtained maize hull appears to be suitable, low cost and efficient adsorbent for removing zn(II) from aqueous solutions.

Background and Up to now various methods has been considered for removing heavy metals such as pb from aqueous solution including using agricultural wastes as low cost adsorbent. The purpose of this study was efficiency evaluation of natural (crude) and citric acid modified rice straw for removal of pb from aqueous solutions. This study was performed at laboratory scale and batch system. We studied the influence of process variables such as pH, contact time, pb concentration and adsorbent dosage. Data from equilibrium study were modeled using isotherm and kinetic models. The concentration of pb was measured by atomic adsorption. Data was then analyzed using ANOVA test. Experimental results showed that the optimum pH and equilibrium time for pb by natural and modified rice straw was 6 and 120 minute, respectively. Removal of pb increased in both adsorbent dosages by increase in pb concentration up to 10 mg/l and increasing the dosage of adsorbents. Adsorption isotherm fitted Temkin model but adsorption kinetic followed pseudo second order. The efficiency of natural rice straw and modified rice straw in removal of pb was 85 and 99%, respectively. According to the results, rice straw especially the modified one could be used as a suitable, low cost and efficient adsorbent for removal of pb from aqueous solutions.

One of the most important sources of environmental pollution is dye from industrial wastewater which is harmful for human health and environment. Therefore, the aim of this study was to evaluate removal of Crystal violet (CV) dye from aqueous solutions by citric acid modified barley straw using response surface methodology.
This research was an experimental-laboratory study. The batch experiment was conducted to evaluate the effect of pH, dye concentration, adsorbent dosage, and contact time on dye removal from aqueous solution. Response surface methodology was applied to appraise the effect of these different variables. The dye concentration in the solutions was measured by spectrophotometer at the wavelength of 594 nm.
The result of this research showed that dye removal efficiency was increased by increasing of adsorbent dosage, pH, and contact time, whilst decreased by increasing of initial dye concentration. The Maximum and minimum dye removal were obtained 94 and 35 percent, respectively. Analysis of variances test showed that the linear model was the best model to explain the interaction of variables.
According to the obtained results, modified barley straw appears to be used as a suitable, low cost, and efficient adsorbent for removal crystal violet dye from aqueous solutions.