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Showing 771 results for Type of Study: Research

A.r Yazdanbakhsh, A Sheikh Mohammadi, M Sardar, H Mohammadi, M Zarabi,
Volume 2, Issue 4 (3-2010)
Abstract

Backgrounds and Objectives: A great part of organic compounds cause more pollution in natural  waters meet, are chemical dye material. Azo dyes have more usage in different industries. Azo dyes not only give undesirable dye to the water but also have mutation potential and carcinogenesis effects in human and cause the production of toxic substances in water environments.The purpose of this study is investigation of iron powder, hydrogen peroxide and iron powder-hydrogen peroxide processes in removal of acid yellow 36 dye from aqueous solutions.
Materials and Methods: This study was conducted in laboratory scale. At this experiment synthetic solution was made from acid yellow 36 dye, and the removal of acid yellow 36 dye was studied by iron powder, hydrogen peroxide and iron powder- hydrogen peroxide processes .Also effect of dye concentration, pH solution, hydrogen peroxide concentration, iron powder concentration and the time of contact on decolorization, were evaluated.
Results: The results showed that iron powder - hydrogen peroxide process, compared to two other  process has high decolorization power. Removal efficacy of iron powder-hydrogen peroxide process with H2O2 =23.33 ml / L, pH =3, iron powder 2000 mg/L and 60 minute ,was about 97.9%
Conclusion:In general this investigation showed that , this method (Iron powder-hydrogen peroxide process) has high efficiency for removal of Azo dyes. But application this method in the industry, should be economically evaluated.


M Eshraghi, B Ayati, H Ganjidoust,
Volume 2, Issue 4 (3-2010)
Abstract

Backgrounds and Objectives : Nitrogen compounds in wastewater are mainly in four types of organic, am- monia, nitrite and nitrate. Total nitrogen concentration in municipal wastewater is usually within 25 to 45 mg/L as nitrogen. The most important problem with nitrogen is its oxygen demand and human health effect.
Materials and Methods: Anaerobic Baffled Reactor (ABR) is a system in which baffles are used to direct  wastewater flow. During 9 months study, a 15 liter modified ABR (104*30*15 cm) with eight baffled com- partments was used for nitrification-denitrification processes. In the seventh compartment, the wastewater was aerated to oxidize ammonia to nitrite and nitrate.
Results : Denitrification was done in the first four compartments with removal efficiency from 60 to 84 per- cent for nitrite and nitrate, respectively. During the shock loading study (4 times of the last influent), a sharp decrease in nitrogen removal rate was observed which was then returned to the previous efficiency after 11 days. Artificial neural network was used to evaluate and process the data in which the observed error in 10 patterns was less than 15 percent.
Conclusion : Anaerobic baffled reactor with an influent of up to 200 mg/L has capability to remove total  nitrogen concentration to less than the standard level of Iranian Department of Environment of 50 mg/L as nitrate and 10 mg/L as nitrogen.


M Panahandeh, M Arastou, A Ghavidel, F Ghanbari,
Volume 2, Issue 4 (3-2010)
Abstract

Backgrounds and Objectives: Landfill site selection is an important action in integrated solid waste management process. Difference criteria should be paid attention in site selection, so using of special methods are necessary to assimilate the criteria. In this research, GIS software and Analytical Hierarchy Process were used.
Materials and Methods: First of all, maps were built in considering to economical, social and environmental factors, in next step, each layer, was graded. Low grade showed non coordination or less coordination and high grade showed more coordination.
Results: Assimilate of graded map in AHP process, separates area into unsuitable, suitable and very
suitable parts.
Conclusion: Very suitable parts can have high priority in decision making and also suitable parts can have high priority for development projects in future.


E Taheri, M Vahid Dastjerdi, M Hatamzadeh, A Hassanzadeh, F Ghafarian Nabari, M Nikaeen,
Volume 2, Issue 4 (3-2010)
Abstract

Backgrounds and Objectives: Drinking water quality after treatment and before reaching  the consumer could be affected by distribution pipes, service lines and Home devices. The structure of water coolers, a home device that are widely used in warm months of the year, could potentially affect the quality of drinking water. The aim of this study was to assess the microbial and chemical quality of water from conventional water coolers.
Materials and Methods : Water samples were collected from 29 water cooler systems at the Isfahan  university of medical sciences. 29 control samples also obtained from the nearest drinking water taps. All samples were examined for total heterotrophic bacteria and physicochemical parameters including temperature, ph, turbidity and heavy metals.
Results: All samples from the water cooler systems complied with the EPA guidelines for total heterotrophic bacteria count. There were no significant differences between the levels of heavy metals in water samples from the water cooler systems and taps. There was only a significant difference between the level of Cu in the water samples from cooler systems and taps
Conclusion: The overall results of this study indicated that the use of water cooler systems from hygienic point of view could not cause any problems for consumers


Z Farahmand Kia, M.r Mehrasbi, M.s Sekhawatju, A.sh Hasanalizadeh, Z Ramezanzadeh,
Volume 2, Issue 4 (3-2010)
Abstract

Backgrounds and Objectives : Heavy metals in dust can enter to the human body through ingestion andinhalation. They can pollute the water and soil resources via atmospheric precipitation and accumulate in the plants tissue and enter human body by water and food. The aim of this study was measurement of the heavy metals in wet and dry atmospheric precipitation and effects of pollution sources at the ground surface on the concentration of heavy metals in the atmospheric precipitations.
Materials and Methods: In this study the zanjan city was divided into 5 zones and wet and dry precipitations were collected in autumn, winter and spring (2008- 2009) from zones. The concentrations of Pb, Cd, Cr and Zn the collected precipitations were determined by Atomic Absorption spectroscopy method.
Results: The averages of concentrations of Pb, Cd, Cr and Zn were 0.082, 0.286, 0.018, and 0.009 (mg/m 2.d)respectively. The correlation coefficients between Pb-Zn was 0.8 (P<0.01) and for Cr-Cd, Cd-Pb, and Cr-Pb were 0.89, 0.58 and 0.61 respectively.
Conclusion: The results showed that the industrial sources of heavy metals play the main role in concentration of heavy metals in wet and dry atmospheric precipitation in Zanjan.The correlation coefficients showed that the lead and zinc result from a common source. This source can be the lead and zinc factories locating around the city. The measurement of heavy metals in atmospheric precipitation shows the effects of anthropogenic sources in air quality. The heavy metals concentration in atmospheric precipitation can be use as air pollution index.


M Khodadadi, M.t Samadi, A.r Rahmani, R Maleki, A Allahresani, R Shahidi,
Volume 2, Issue 4 (3-2010)
Abstract

Backgrounds and Objectives: Water contamination by pesticides is considered as an environmentalproblem today. In terms of agricultural development and diversity of plant pests, the use of pesticides has been increasing. Hamedan province has a suitable agricultural condition, it has enjoyed significant development in this respect. Among all the cities of Hamedan province, Hamedan city has the highest rank in tiller crops. Therefore, yearly use of pesticides is increasing in this area which could be a serious threat to water resources of the city. The aim of this survey was determinaton of Organophosphorous and Carbamat pesticides residue in drinking water resources of Hamadan in 2007.
Materials and Methods: In this survey, 126 water samples were collected from 7 drinking water resources of Hamedan during 12 consecutive months in 2007. for determination of these pesticides,two methods (solid- phase extraction and Liquid-Liquid extraction) were adopted .and samples were analyzed by means of HPLC and GC/MS applying standard methods.
Results: Final results showed that the most concentration of Chlorpyrifos and Carbaryl pesticides were found to be about 3.85 ppb (part per billion) and 1.8 ppb in spring and June respectively the maximum concentration of Diazinon was about 36.5ppb in October (autumn).The minimum concentration of the three pesticides was detected in winter. According to the statistical test Two - Way ANOWA there were significant differences among pesticides concentrations in the water samples in different seasons (p<0.05) . However, there wasn't a significant difference in pesticides concentrations in surface and ground water samples(p>0.05).
Conclusion: Different studies have shown that pesticides residue concentration in water samples have a relationship with the amount of pesticides used in an area, physical and chemical refractory properties of pesticides and environmental conditions. Thus, using resistant pollutants such as pesticides will be a serious threat to health of water consumers if they are not properly controlled.


R Nabizadeh, Sh Salehi, M Younesian, K Naddafi,
Volume 2, Issue 4 (3-2010)
Abstract

Backgrounds and Objectives:Skin cancer is the most frequent malignancy in Iran. Exposure to the excessive ultraviolet radiation is an important factor in creating skin tumors. The purpose of this study is to determine how the ultraviolet index has been distributed in all townships throughout the country, to determine different kinds of skin cancer and to evaluate a geographical distribution of skin cancers with regard to the UV geographical distribution.
Materials and Methods: This study is ecologic, descriptive and analytical in nature. A total number of 6921 skin cancer cases registered at the Center for Disease Control of Iran in 2004 were thoroughly analyzed and UV data were collected from the world wide web. With the help of ArcGIS software and SPSS, the statistical analysis was done.
Results:The incidence rates were 10.13 for the total skin cancer, 7.53 for basal cell carcinoma, 1.79 for squamous cell carcinoma and 0.39 for malignant melanoma per 100000 population of Iran. The mean ultraviolet index differed from 9 in July to 3 in January. The correlation between the skin cancer incidence at the level of districts and ultraviolet index was not significantly observed.
Conclusion:Skin cancer is a public health problem in Iran. Further research in this regard would lead to skin cancer registration improvement and more understanding of different climatic, cultural and behavioral factors in developing skin tumors. With this knowledge the possibility of more effective prevention of the most prevalent cancer in Iran can be created.


N Jaafarzadeh Haghighi Fard, A.r Talaiekhozani, M.r Talaiekhozani, S Jorfi,
Volume 2, Issue 4 (3-2010)
Abstract

Backgrounds and Objectives:Propylene glycol is applied in many industries as raw material and can be released to the environment through wastewater of such industries. The biological treatment of solutions containing high concentration of propylene glycol is difficult and some problems can be observed during this process. The main objective of this study was the investigation of electrochemical degradation of propylene glycol and the parameters influencing on improving removal efficiency.
Materials and Methods: In this study the degradation of propylene glycol was made by passing an electrical current though the synthetic wastewater containing propylene glycol. In order to investigate this process several types of electrode with applied voltage ranging between 5 to 50 V was used. Due to the effect of NaCl concentration on removal efficiency which was mentioned in the literature, the experiment was performed for different NaCl concentrations.
Results: In optimum condition, the maximum removal efficiency of propylene glycol (based onCOD) was obtained equal to 90%. The results showed that rising applied voltage, NaCl concentrationand retention time increase the removal efficiency. The optimum retention time was obtained equalto 50 min. The maximum removal was obtained when aluminum electrode was used. It can beattributed to the production of coagulant material such as Al+3 during this process.
Conclusion: The results revealed that this process can be useful for treating the industrial wastewatercontaining propylene glycol.


A. Almasi, A.h Hashemian, E. Amirpour, A. Dargahi, M. Mahmoudi,
Volume 3, Issue 1 (4-2010)
Abstract

Backgound and Objectives: The aim of this study is to investigate water consumption, domestic wastewater generation and organic matter concentration, based on both, economical income and meteorological temperature.
Materials and Methods: The method of this study is descriptive and analytical. A checklist was used to collect data on economical income. Water consumption was obtained based on water bills. Wastewater generation and organic matter such as biochemical oxygen demand (BOD) per capita/ day were measured every four hours, during a day in three regions of Kermanshah city: Kasra, Ellaheiah and Taavon.
Results: Comparing water consumption in winter and summer showed significant difference in three regions, mentioned above. The water consumption was (398 ± 75, 291 ± 48 and 188 ± 50) for warm climate and (200 ± 25, 188 ± 35 and 140 ± 41) for three regions respectively in cold weather. In spite of an apparent difference in BOD in three regions, it was not significant statistically. Water consumption has strongly considerable relationship with economical income (r =0.988, P_value <0.001), while the generated wastewater in these regions were not different, statistically for warmclimate (220 ± 60, 204 ± 15 and 170 ±34), and in cold weather (170 ± 21, 158 ± 31 and 112 ±29), also the generated wastewater did not have considerable difference in cold climate. This study confirms that, the effects of these two parameters, i.e.monthly economical income and environmental temperature on water consumption, generated wastewater and biodegradable organic loading per capita/day is considerable. It was concluded that water consumption and wastewater generations were much more in warm climate than in cold weather.
Conclusion: Finally through this study the estimation of water consumption, wastewater generation and BOD concentration becomes possible, which is beneficial for establishment of water consumption.


H. Asilian, G.r Moussavi, M. Mahmoudi,
Volume 3, Issue 1 (4-2010)
Abstract

Backgrounds and Objectives:Much attention has been recently paid on using waste materials as adsorbents for removal of contaminants from water and wastewater. A new low cost waste was examined for its capacity to adsorb RR198, an azo reactive model dye, from an aqueous solution.
Materials andMethods: The waste was dried, powdered and characterized before being used as an adsorbent. The effects of pH (3-10), adsorbent dose (0.2-3 g), dye concentration and contact time on the adsorption efficiency were investigated. Equilibrium study data were modeled using Langmuir and Freundlich models.
Results: The characterization analysis indicated that itwas composedmainly of ferric hydroxide. The powder had a BET and average pore size of 107 m2/g and 4.5 nm, respectively. The results showed that dye removal was highest at a solution pH of 7 to 8 and a powder dose of 2 g/L. The RR198 removal percentage decreased from 100& to 43& at 140 min contact time when the concentration of dye was increased from 25 mg/L to 100 mg/L, at optimum pH and dosage. The Langmuir equation provided the best fit for the experimental data. The maximum adsorption capacity was calculated to be 34.4 mg/g.
Conclusion: According to the obtained results, the water coagulation waste sludge appears to be a suitable low cost and effcient adsorbent for removing reactive azo dyes from waste streams.


A Ghanavati Hormozi, K. Naddafi, R. Nabizadeh Nodehi, N. Jaafarzadeh,
Volume 3, Issue 1 (4-2010)
Abstract

Background and Objectives:Fanavaran petrochemical company is located on the shore of Persian Gulf on west south of Iran, Imam Khomeini Bandar, petrochemical special economic zone with of 25 hectares area. Two units of this company, methanol unit with production capacity 1000000 tons/years and monoxide carbon unit with 140000 tons/years were studied for determination and emission factories of SO2, CO2, CO, NO, NO2, NOx Gases.
Materials and methods: With attention to project goals, for implementation of this project 14 months took into from April 2008 till June2009.For goals provide of mentioned research on this basis,case sampling were done from 3 emission sources by using of direct reading device of gas concentration according to standard methods of United State Environmental Protection Agency.
Results: Results of the study indicate that concentration of issued pollutant gases from these units is in the level lower than Iran department of environment standard level. The total amount of emission Factory of SO2, CO2, CO, NO, NO2, NOx gases diffused from these units are11.7×10-6 , 81/8×10-6, 0.14×10-6, 431.5×10-6, 19.2×10-6 , 681.2×10-6kg /tons million production in a year respectively.
Conclusion:Parameters which optimization is performed in accordance with them, include of additional air percentage, exit air temperature from pre heater, and fuel type, in fact with regarding these 3 factors. effects, the work is done in a manner that the amount of pollutants diffusion is near to minimum and the selected best fuel.


M.t Samadi, M. H Saghi, M. Shirzad, J. Hasanvand, S. Rahimi,
Volume 3, Issue 1 (4-2010)
Abstract

Backgrounds and Objectives:In Iran , indicated that the municipal landfill leachate has been one of the major problem for environment. In the operations, leachate treatment is a very difficult and expensive process. Although, young leachate can be treated easily by biological treatment, COD removal efficiency are usually low due to high ammonium ion content and the presence of toxic compounds such as metal ions. Treatment of leachate is necessary.The aim of this study is reduction of Chemical Oxygen Demond (COD) and Total Suspended Solids (TSS) from hamedan city sanitary landfill leachate by three coagulants: alum, PAC and ferrous sulfate.
Materials and Methods: This experimental study was conducted to investigate the effect of treatment of landfill leachate by a coagulation-flocculation process. The effects of different amounts of coagulant and different pH values on the coagulation processes were compared.
Results:Result shown the high efficiency for reduction of CODby PAC in pH=12 and concentration of 2500(mg/l (62.66%), and by alum in pH=12 and concentration of 1000 (mg/l) (60%) , by ferrous sulfate in pH=2 and concentration of 1000 (mg/l) (70.62%). Also result shown the high efficiency for TSS removal by PAC in pH=12 and 2500(mg/l) concentration of PAC was 58.37%, with alum in pH=2 and 1500 (mg/l) concentration of alum was39.14% , by ferrous sulfate in pH=7 and 2500(mg/l) concentration of ferrous sulfate was 35.58%.
Conclusion:The best coagulant for COD removal is ferrous sulfate.The physico-chemical process may be used as a useful pretreatment step, especially for fresh leachates, prior to post-treatment (polishing) step for partially stabilized leachates.


A. Alizadehdakhel, A. Ghavidel, M. Panahandeh,
Volume 3, Issue 1 (4-2010)
Abstract

Backgrounds and Objectives: The dispersion of particulate matter has been known as the most serious environmental pollution of cement plants. In the present work, dispersion of the particulate matter from stack of Kerman Cement Plant was investigated using Computational Fluid Dynamics (CFD) modeling.
Materials and Methods: In order to study the dispersion of particulate matter from the stack, a calculation domain with dimensions of 8000m × 800m × 400m was considered. The domain was divided to 936781 tetrahedral control volumes. The mixture two-phase model was employed to model the interaction of the particulate matter (dispersed phase) and air (continuous phase). The Large Eddy Simulation (LES) method was used for turbulence modeling.
Results: The concentration of particulate matter in the whole calculation domain was computed. The predicted concentrations were compared to the measured values from the literature and a good agreement was observed. The predicted concentration profiles at different cross sections were analyzed.
Conclusion:The results of the present work showed that CFD is a useful tool for understanding the dispersion of particulate matter in air. Although the obtained results were promising, more investigations on the properties of the dispersed phase, turbulent parameters and the boundary layer effect is needed to obtain more accurate results.


M.a Zazouli, E. Ghahramani, M. Ghorbanian Alahabad, A. Nikouie, M. Hashemi,
Volume 3, Issue 1 (4-2010)
Abstract

Backgrounds and Objectives: One of environmental outcomes in industrial towns is developing environmental pollution such as production of industrial wastewaters. These industrial wastewaters should be appropriately treated before entering to receiving waters. However we can't solve environmental anxieties by establishing of wastewater treatment plants alone but permanent and regular assessment of these treatment plants performance is necessary for achieving environmental standards. Thus, this research has been done in order to investigation of activated sludge performance in wastewater treatment of Agghala industrial town in Golestan province.
Materials and Methods: This cross-sectional study implemented in sewage treatment plant laboratory of Agghala industrial town in Golestan within 12 months at 2007. Chemical Oxygen Demand (COD) parameter determined twice in week, But Biochemical Oxygen Demand (BOD) test accomplished weekly. pH measured by pH meter daily. Experiment of total suspended solids (TSS) and total dissolved solids (TDS) carried out every 10 days. All tests accomplished according to standard method for water and wastewater examination (2005). Then data analyzed using excel 2007.
Results: The average of BOD, COD and TSS in influent was 11196.17, 1854.58, 1232.25 mg/L respectively.Maximum influent organic loading rate was related to Shahrivar andMehr months. The total average of removal efficiency for BOD, COD and TSS was calculated 99.66, 98.2, and 97.6% respectively.
Conclusion:Quality of this treatment plant effluent was according to effluent disposal standards all over year. In sum, efficiency of this treatment plant (activated sludge system) was very good ininfluent pollutant removing. However occasionally effluent was not adapted with environmental standards but these deficiencies is solvable by accurate management and supervision on flow rate and influent organic loading rate easily.


H. Hashemi, M.m. Amin, B. Bina, H. Movahedian Attar, H. Farrokhzadeh,
Volume 3, Issue 1 (4-2010)
Abstract

Backgrounds and Objectives:Today, due to health, environmental and economical problems, of chlorine application, UV radiation is better option than chlorine for disinfection of effluent. The aim of this study was disinfection of secondary effluent with UV radiation.
Materials and Methods: Two types of UV disinfection system including low pressure (LP) and medium pressure (MP) was used to disinfection of Isfahan North Wastewater Treatment Plant (INWWTP) effluent without pretreatment. Single and combined lamps were operated to evaluate the removal of total and fecal coliforms (TC and FC), and fecal streptococcus (FS). TSS, iron, hardness, UV absorption and transmittance were analyzed in order to observe the fouling of the quartz sleeves.
Results: After using LP lamp with dose of 161 mws/cm2, TC and FC content was declined to standard level (1000 TC, and 400 FC/100ml). In addition, disinfection with MP lamp was led to FS content of 400 MPN/100 mL. Combination of LP and MP, with dose of 460 mws/cm2 could be met the environmental requirements of TC & FC, and the FS count was reached to 400 MPN/100 mL with dose of 237 mws/cm2. Maximum photo-reactivation percentage of coliforms after LP and MP lamps were appeared 15 and 3 percent respectively, while it was not observed for FS.
Conclusion: High fluctuation in secondary effluent quality of INWWTP mainly TSS concentration was caused to decline of the UVT value. Therefore, disinfection of effluent by LP, MP and even combined both systems are not applicable in conventional UV dose. Hence, using advanced process unit before UV disinfection system is necessary for removal of TSS.


B. Mortazavi, L. Rasuli, H. Kazemian,
Volume 3, Issue 1 (4-2010)
Abstract

Backgrounds and Objectives: Hexavalent Chromium is an important contaminant in surface and ground waters and removal from contaminated water and waste water has received interest in recent years. Modified Zeolite with cationic surfactant can remove Cr(VI) from contaminant water. The aim of this research is investigation of Cr (VI) removal from aqueous solutions and its effective parameters by using Modified Zeolite with cationic surfactant.
Materials and Methods:In this research the efficiency Of Cr(VI) removal and impact of the important parameters including adsorbent dose, pH and contact time in the batch system was studied.
Results:The results of this research showed that SMZ can remove more than 90 & Cr(VI) in the concentration 0.1-1.25 mg/l with optimum dose 0.3 gr and pH=6 120 minute in contact time.
Conclusion: Modified natural zeolite have significant potential inCr(VI) removal fromcontaminated water.Maximumpercent removal ofCr(VI)was in the pH=6 and 120minute contact time.Adsorption data in the equilibrium was fitted with Langmuir isotherm. Separation factor was between 0 and 1 that indicates the favorable condition for Cr(VI) adsorption on the SMZ.


M.t Samadi, M.h Saghi, K. Ghadiri, M. Hadi, M. Beikmohammadi,
Volume 3, Issue 1 (4-2010)
Abstract

Backgrounds and Objectives:Phosphate discharges from domestic and industrial waste water to water bodies. High concentrations of phosphate in water stimulate the eutrophication phenomenon that causes taste and odor in water, losing dissolved oxygen and aquatic life in rivers or surface waters. Aim of this study is survey of phosphate adsorption on simple nano zeolite Y and nano zeolite Y that was modified with a cationic surfactant (HDTMA-Br).
Materials and Methods:In This study we used simple nano zeolite Y and nano zeolite Y in form of Surfactant Modified Zeolites (SMZs) using batch tests to adsorption of Phosphate fromAqueous Solutions. The adsorbants were contacted with different initial phosphor concentrations (5, 10 and 15 mg/l), pH (4, 7, 12), contact time (30, 60, 90, 120, 150 and 180 minutes) and weight of adsorbant (0.2, 0.4, 0.6, 0.8 and 1g). the extracted solution was determined for Phosphate concentration by the ammonium molybdate and tin chloride method with spectrophotometric detection at 680 nm. Results:Results of this study show that, with increase in contact time, decrease in pH, increase in zeolites concentration and decrease in initial phosphate concentration, the removal efficiency increased. And the Both isotherm of Langmuir and Freundlich models (r2 > 0.997 and r2 > 0.996 respectively) were agreement with adsorption equilibrium of phosphate. Reduced Chi-Sqr For Langmuir and Freundlich models were (0.00079) and (0.0011) respectively. Pseudo first-order kinetic models fits well with experimental data (r2>0.963).
Conclusion: From this survey, it is concluded that performance of modified nano zeolite Y for adsorption of phosphate in same conditions is better than non-modified zeolite Y. In general the modified nano zeolite Y presented a good profile for removal of phosphate. Therefore SMZs is a suitable candidate for removal of Phosphate molecules from contaminated solutions in contaminated waters.


M. Fahiminia, A. Paksa, A. Zarei, M. Shams, M. Fazlzadeh Davil, H. Bakhtiari, M. Norouzi,
Volume 3, Issue 1 (4-2010)
Abstract

Backgrounds and Objectives: Domestic sewers and wastewater treatment plants are suitable places for the growth of some types of Cockroaches. Annually the water and wastewater company of Qom city make considerable attempts to overwhelm the problem. The current study is aimed to determine types of Cockroaches and select the optimal methods for their control.
Materials andMethods: In this study, 120 manholes are selected in different locations of Qom city, the numbers of Cockroaches are counted and the Cockroaches are classified into different groups. Then, each group are faced to different insecticides Including Simperator, Diazinon , Dursban Ec, Faikam, Sipermetrin, Icon, Deltametrina and Sulfac. One group of manholes was considered as blank sample during one month. Counting and determination of Cockroaches in these manholes conducted before using insecticides and also five months after it.
Results: the study showed that all sewers were 100% polluted by Cockroaches. The number of Cockroaches in manholes range from minimum 4 to maximum 3600 in each manhole. The applied of insecticides including Dursban Ec, Simperator, Sulfac, Dursban, and Deltametrina are used 2 gr in 100 square meter of area of each sewer. The Cockroaches population reduced to approximately zero after application of these insecticides. Spraying sewers by Simperator controlled 100% of Cockroaches.
Conclusion: the most effective method for the control of Cockroaches was usage of 2 gr of Dursban (Ec) in squaremeter of area in the beginning of warmseason.If we use 1-1/5months interval between the time of spraying insecticide in selected wells, with using simperator and dursban (Ec) we can overwhelm Cockroaches using Simperator and Dursban Ec. The results of statistical analysis show that reduction of number of coackroaches in one month after using poison is significant (P-value< 0.05). But after 5months it lose meaningful in all of them.Also, reduction of number of coackroachesin blank manholes was not statistically significant.


B. Mortazavi, B. Ramavandi, G.r Mousavi,
Volume 3, Issue 1 (4-2010)
Abstract

Background and Objectives: Nowadays nitrate concentrations in surface water and especially in groundwater have increased in many locations in the world. Since nitrates cause many health and environmental concerns, increased nitrate concentrations in groundwater have led to rendered aquifers unusable as water sources. So, as the water demand is still increasing the throughout the world, decreasing the nitrate concentration in drinking water is imperative. Magnesium powder has been determined to be potentially useful for the removal of nitrate in the water environment. This research is aimed at subjecting the kinetics of nitrate chemical reduction by Mgo to an analysis of some factors affecting the chemical denitrification.
Materials and Methods: Nitrate concentrations determined in 220 nm using a spectrophotometer.To determine the performance of nitrate removal by Mg0 powder, double distilled water was used for preparation of reagents and simulation of contaminated water with nitrate.All experiments were triplicate and the averaged results were reported.
Results: Kinetics analysis from batch studies revealed that the denitrification reaction with Mgo powder appeared to be a first-order with respect to substrate and the observed reaction rate constant (kobs). The effects of mixing intensity on the denitrification rate suggest that the denitrification appears to be coupled with oxidative dissolution of magnesium through a largely mass transportlimited surface reaction. Also in the denitrification by Mgo determined that Mgo dose related with kobs ( R2>0/99 )S
Conclusion: In this research was determined that denitrification effectively by Mg0 powder can achieved in a wide range of concentrations under atmospheric conditions and without pH controlling within short reaction time. Denitrification rate was related to some parameters such as contact time, Mgo dosage, mixing rate and initial nitrate concentration.

 


M. Dahaghin, M. Shariat, M. Norrozi, M. Vigeh, F. Ramezanzadeh,
Volume 3, Issue 1 (4-2010)
Abstract

Backgrounds andObjectives:The objective of the present study was to evaluate the potential effect of environmental exposure to toxic metal (cadmium) on pregnancy outcome and fetal growth.
Materials and Methods: 330 normal pregnant women were randomly selected from vali-e-asr hospital, from July 2003 through Feb. 2005. Cadmium was measured in umbilical cord blood and mother whole blood of postpartum women without occupational exposure to metals in Tehran, Iran, using inductively coupled plasma mass spectrometry
Result: Whole blood cadmium and cord blood cadmium ranged from 0/00 to 6/30 &mug/L ,respectivly. in the group higher level of maternal blood cadmium (> 0.40 &mug/L) 1cm decrease was seen in neonatal birth height. (p = 0.007) There was a significant association between cadmium exposure and birth weight.Mann-whitney test showed that, maternal blood cadmium level, was significantly negatively associated with neonatal birth weight (z = -1.83, P < 0.06).
Conclusion: It was concluded that environmental exposure to cadmium significantly reduces neonatal birth height.



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