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UV-Lamp Intensity Determination Without Use of Radiometer
Ar Mesdaghinia, F Vaezi, E Dehghanifard, Ah Mahvi, M Alimohammadi,
Volume 1, Issue 1 (10-2008)
Abstract

Background and Objectives: Measurement of light intensity is a recommended practice for insuring the delivery of required germicidal dose in disinfection operations by UV lamps. Use of sensitive to light chemicals which is the base of actionometeric methods could be considered as a suitable manner for estimating the intensity of UV lamp in circumstances that special radiometers are not available.
Materials and Methods: lodide-iodate mixture was used as an actinometer for this study. The light intensities of a UV lamp (LP 25W) were first determined by a special UVC ‌radiometer at certain distances from the lamp. Then the test of determining the suitable period of time for irradiation of actinometer was accomplished.  Finally، the color changes of iodide - iodate solutions at the predetermined distances were evaluated at the wavelength of 352 nm. The latter analysis can be done by a common (visible) spectrophotometer.
Results:‌ Results indicated that use of this actinometer is more suitable at the distances of 35 to 60 cm from the center of the lamp bulb، since iodode-iodate solution has a detectable color change at this range of distance in one minute irradiation which may be considered as a reasonable time for actionmeteric operations.
Conclusion:  Although all kinds of actinometers should not be regarded as precise as special radiometers and there would be need to use pure chemicals for actinometeric determination of light intensity، it can be claimed that the recommended procedure in this study which is the newest actinometeric method can be used in acceptable evaluation of UV intensity with least difficulty in providing necessary instruments.


Study of Natural Organic Matter Characteristics and Fractions in Surface Water Resources of Tehran
Ma Zazouli, S Nasseri, A Mesdaghinia,
Volume 1, Issue 1 (10-2008)
Abstract

Background and Objectives: Natural organic matters (NOMs) are abundant in natural water resources and in many ways may affect the unit processes in water treatment. Although NOMs are considered harmless but they have been recognized as disinfection by-products (DBPs) precursors during the chlorination process. Formation of DBPs highly depends on the composition and concentration of NOMs. The objective of this study was to determine natural organic matter and its fractions concentrations in the surface water sources of Tehran.Materials and Methods: Water sampling was conducted monthly between May to July in three rivers of Lar, Jajrood and Karaj, as the main drinking water supplying sources in Tehran. Quantitative parameters of pH, EC, UV254 and DOC were studied based on standard methods. The XAD-7 resin method was used for fractionation of NOMs.Results: Results showed that NOM concentrations in Lar, Jajrood and Karaj rivers were 8.53, 12.9 and 11.3 mg/L, respectively. The HPO (hydrophobic) fraction was predominant compared to the HPI (hydrophilic) fraction in water samples. The mean of total percent of HPO and HPI fractions were about 57% and 43%, respectively.Conclusion: Since the hydrophobic NOM fraction exhibits higher trihalomethane formation potential (THMFP) than hydrophilic part, Tehran water chlorination exhibits higher THMFP than haloacetic acid formation potential (HAAFP). The information obtained from this study may be further employed in the design of the control techniques and management strategies for the water treatment plant, especially for DBPs reduction.


Economic Comparison of Standard Method with E.Jurdo Simplified Method to Measure Linear Alkyl Benzenesulfonates in Municipal Wastewater
M Pirsaheb, A Almasi, A.a Zinatizade, R Khamutian, S Delangizan,
Volume 4, Issue 2 (9-2011)
Abstract

Background and Objectives: Linear alkyl benzene sulfonates are widely used as surfactants in formulated detergent products. Because of their use in household and industrial detergents, LAS is discharged into wastewater collection systems and subsequently entered to wastewater treatment plants. Therefore, it is important to determine the concentration of LAS with accuracy. They are usually determined by standard method which is time-consuming,tedious and requires great quantities of chloroform. IN 2006 E.Jurado et al proposed a simplified method for measurement of LAS. In the present work the standard method and E.Jurado simplified method was compared economically.
Material and Methods: In this work NPV method was used for accounting the cost of initial investment, consumable material, non-consumable equipment and annual cost of staff and finally Net Present Value was calculated for them separately. The rate of interest was considered 15%.
Results: calculation showed initial investment, annual cost of staff and materials for standard method 13351981, 499968 and 1710981 RLS, respectively. And these costs for simplified method were 12048202, 83328 and 58202 RLS, respectively. Finally NPV for standard method and simplified method were equal to 30360709 and 14681848 RLS.
Conclusion: The method proposed by E.Jurdo et al is simple, time consuming and more economical than standard method .This technique can be suggested applying to the routine measurement of LAS in wastewater treatment plants.


Effect of Persian Gulf Saline Water on Quality of Asaluyeh Plain Groundwater and Determine the Origin of Nacl Anomaly
Zahra Sajadi Mian Ab, Nasrollah Kalantari, Jaber Mozafarizadeh,
Volume 5, Issue 1 (4-2012)
Abstract

Background and Objectives: Due to population intensity and industrial activities, quality of groundwater is important in Bushehr province and in particularly in coastal areas. The salinity of groundwater in Asaluyeh plain is increasing from the heights towards the Persian gulf and in some places are not even applicable for irrigation.
Materials and Methods: In order to explore the source of the chloride anomaly, groundwater samples were analyzed and compared with the Persian Gulf samples. Also Water Samples Different diagrams were determined and the reasons of water salinity of Asaluyeh Plain were investigated.
Results: The results of chemical analyses showed the groundwater excessive salinity, especially near the sea. Based on correlation matrix, the highest correlation between the sodium and chlorine ions was observed.
Conclusion: The factors influencing on groundwater salinity in the plain varies and arising from solution of halite and gypsum from surrounding formations, suddenly increas sodium chloride in some parts of plain and forming Cl-Na water type. The results indicated that the Groundwater Type of Asaluyeh is Cl-Na and therefore it is classified as non-potable water.


Investigation of Nano Particles Efficiency  Prepared from Cedar Fly Ash (Zizyphus Spinachristi) for  Lead (Pb+2) Removal from Aqueous Solution
Laleh Divband, Majid Behzad, Saeed Boroomand Nasab, Sara Divband,
Volume 5, Issue 1 (4-2012)
Abstract
MicrosoftInternetExplorer4 Background and Objectives: Existence of Heavy metals in water resources is one of the most important environmental problems in many countries. These metals have dangerous effects on human health. The purpose of this study is  to investigate and compare lead removal by nanometer and millimeter absorbents of Zizyphus Spinachristi fly ash.
Materials and Methods: This study was non-continuous experiment which was implemented under laboratory conditions with and by changing effective factors such as pH (3, 4, 5, 6, 7, 8), contact time (5, 10, 15, 30, 45, 60, 90, 120 minutes) and adsorbent concentration (1, 2, 5, 10, 20 and 50 mg/ L). The data was fitted based on four models including Ho et al, Lagergern, Lungmuir and Freundlich which the first two models used for absorption kinetic and the latter two considered as absorption isotherm.
Results: The Result of this study showed that as the pH increases from 3 to 5 adsorption efficiency increased as well. Furthermore, when pH was over 5, the metal ions settled down. With increasing contact time, adsorption efficiency increased as well. With increasing the amount of nanometer as an adsorbent, removal efficiency increased and then decreased. Also the adsorption process followed precisely Ho et al kinetic and Langmuir isotherm, for both absorbents.
Conclusion: Based on the obtained results, specific area of the nano particles was more than millimeter particles (29.56 m2/g & 17.80 m2/g), therefore adsorption capacity of nano absorbent was four times more than adsorption capacity of millimeter (19.93 mg/g & 17.80 mgr/g). Furthermore, the findings concluded high capability of nano particles towards Sorption of lead ions (Pb) from aqueous solutions.


Investigation of synthesized silica coating Fe3O4 nanoparticles efficiency in removal of NOM from water
E. Karimi Pasandideh, R. Rezaei Kalantary, S. Nasseri, A. H. Mahvi, R. Nabizadeh, A. Esrafili,
Volume 7, Issue 3 (5-2014)
Abstract

Background and Objective: The presence of natural organic materials (NOM) in water resources affects its quality (i.e. color, odor, and taste). In addition, it leads to the fouling of filters and membranes and reduces water treatment efficiency during flocculation/ coagulation. Moreover, NOM reacts with disinfectants and produces byproducts (DBPs), which are harmful to human health. Magnetic nanoparticles have been reported as effective adsorbents for the removal of pollutants from the aqueous media. In this study, we applied SiO2coating on these nanoparticles in order to enhance their stability and dispersion in aqueous media and investigated their capability in NOM adsorption from water. Materials and Methods: Iron oxide magnetic nanoparticles were prepared by co-precipitation. Then, we added Tetraethoxysilane (TEOS) to the solution in order to coat it with SiO2 . The adsorbent characteristics were determined by SEM and XRD. Then, we carried out the adsorption experiments under different pH(3-12) and contact time (5-240 min)performance conditions. The adsorption kinetic was determined with respect to different Humic acid adsorption times. Later, we determined the effect of different concentrations of adsorbent on different concentrations of Humic acid, and Langmuir and Freundlich coefficients based on the optimum conditions. Results: The morphology investigation of adsorbent showed the average size of Fe3O4/SiO2nanoparticles was 30-130 nm. The pH value of 10.5 and the contact time of 90 min at room temperature were determined as optimum conditions for removal of humic acid using Fe3O4/SiO2 nanoparticles. The maximum adsorption capacity of Fe3O4/SiO2 was192.30. The adsorption isotherm was fitted well by Langmuir model (R2>0.90) and the pseudo-second order model (R2>0.98) could better explain humic acid adsorption. Conclusion: Having high number of active surface sites, magnetic properties, easily separation using magnetic field, and its cost-effectiveness, the Fe3O4/SiO2 nanoparticles could be used as an efficient adsorbent in removal of humic acid from water.


The frequency and type of events of Chaharmahal Bakhtyari nomads in the first half of 2014
A Shahbazi, M Falakzadeh, F Shahin, S.h Frahzad Boroujeni, E Mehrabi,
Volume 8, Issue 2 (8-2015)
Abstract

Background and Objectives: Events are the second leading cause of disability and one of the problems that can cause physical and psychological disorders, and in more severe cases lead to death. Therefore, at the first, the risks must be identified, so that one can offer how to confront and eliminate risk. Thus, this study aimed to determine the frequency and type of events among nomads. Materials and Methods: This cross-sectional study was performed on 534 nomad in Chaharmahal- Bakhtiari Province during first half of 2014. The data collection was through interviews based on a predetermined checklist and finally the data gathered were analyzed using SPSS (Ver.19) software and descriptive statistics. Results: It was found that out of 534 nomads, 144 were female (26.97%) and 390 male (73.03%) and age average of them was 26.32±24.12. These people are often faced with 18 types of events in their location or during their shifting the most frequent one is caused by sinking of thorns and sharp rock aggregates in their organs during labor activities (62.46%) and the least frequent one was hurt caused by lightning (0.19%) and electric shock by electrical tower (0.19%). The results showed that there was a significant relationship between sex, season of the year, the summer location, and accident rate (P ≤0.002) but there was no significant relationship between the nomads and clans of the study and event rate. Conclusion: Like many diseases, events are preventable, and this requires the development of knowledge about the principles of safety during migration and housing. Therefore, it seems that for the preserving nomadic population and reducing lost caused by these events, the national event management centers and emergency medical centers should have better planning in this field.


A comparative study on the effect of health expenditure and air pollution on economic growth in developed and developed countries
N Shiralipour, Mr Mirzaee Nejad,
Volume 11, Issue 4 (3-2019)
Abstract
Background and Objective: Health expenditures and environmental pollution are indicators of development. Therefore, the aim of this study was to examine the effect of health per capita costs and the impact of carbon dioxide emissions (CO2) as an indicator of environmental pollution on the growth of selected developed and developing countries.
Materials and Methods: The effect of health expenditures and air pollution on economic growth was studied based on the data of two groups of developed and developing countries (2000-2015) and the use of econometric methods.
Results: The fitting of the equations confirmed the significant effect of the health expenditure per capita and CO2 emission on the economic growth of both groups of countries. One percent change in these expenditures resulted in 0.029 percent economic growth in the developed countries and 0.054 percent in the developing. Also, the effect of CO2 release on the economic growth was -0.011 and -0.073.
Conclusion: Health has a direct impact on economic growth. Health has a positive effect on the economic growth by reducing health costs (and spending these resources in other areas) and by increasing labor productivity through increasing life expectancy and useful work time. Also, increasing air pollution has a negative effect on the economic growth of these countries.
 

Needs assessment and prioritization of establishment of rural wastewater management facilities in order to supply a safe and alternative water source in the provinces of Iran with severe water stress
M Ansari, M Fahiminia, M Farzadkia,
Volume 11, Issue 4 (3-2019)
Abstract
Background and Objective: Rural wastewater management is recognized as one of the pillars of sustainable development. Therefore, the purpose of this study was to assess needs and prioritization of establishment of rural wastewater management facilities in order to supply a safe and alternative water source in the provinces of Iran experiencing severe water stress.
Materials and Methods: This is a cross-sectional descriptive study which was carried out in rural areas of the provinces with severe water stress (South Khorasan, Khorasan Razavi, Fars, Isfahan, Yazd, Semnan, Qom, Sistan and Baluchistan) in 2017-2018. In this study, the number of sample rural areas was calculated by Cochran method and the determination of the sample rural area was done by stratified sampling. The data related to the sample rural area was collected using a validated constructor questionnaire.
Results: The results of this study showed that the difference among all the studied provinces in terms of their priority in establishing rural waste water management facilities to provide a safe and alternative water source was very low. The provinces of Isfahan, Semnan and Fars were rated at 76 out of 100, while the provinces of South Khorasan and Sistan and Baluchestan scored 71 points.
Conclusion: With emphasis on comprehensive decision making criteria based on sustainable development, the results of this study showed that the provinces with severe water stress have a high priority regarding the establishment of rural sewage management projects in order to provide a safe and alternative water sources.
 

Removal of 2,4-dichlorophenoxyacetic acid and 4-chloro-2-methyl phenoxyacetic acid herbicides from aquatic environments by a novel polymer magnetic nanoparticles
Alireza Hajighasemkhan, Lobat Taghavi, Elham Moniri, Amir Hessam Hassani, Homayon Ahmad Panahi,
Volume 13, Issue 1 (4-2020)
Abstract
Background and Objective: Increased use of pesticides and chemical fertilizers in agriculture in order to increase the productivity of fertile lands has led to pollution of water resources with a variety of pollutants, including herbicides. In this study, a new polymer magnetic nanoadsorbent named PV/S-g-3D-GO/N was synthesized and used to remove 2,4-D and MCPA herbicides from aquatic environment.
Materials and Methods: To investigate the synthesized nanoadsorbent structure FTIR, FESEM, TEM, XRD, VSM and TGA techniques were used and the effect of parameters affecting the optimal removal of herbicides by the adsorbent, including pH, temperature, contact time, adsorption dose and initial herbicide concentration was investigated. The kinetic, isotherm and thermodynamic studies of adsorption were also investigated.
Results: The results showed that in the optimal adsorption conditions including pH 3 for both herbicides, contact time of 180 min for 2.4-D herbicide and 300 min for MCPA herbicide, absorption dose 5 g/L and temperature 50°C for both herbicides, the maximum absorption capacity (qmax) was 5.62 mg/g for 2.4-D and 4.94 mg/g for MCPA. The synthesized nanoparticles that were used to remove 2,4-D and MCPA herbicides from real samples were totally successful (100% removal efficiency). For both herbicides studied, the isothermal data followed the Longmuir model (2,4-D: R2 = 0.995; MCPA: R2 = 0.998), and the kinetics of the adsorption process was a pseudo-second-order model (2,4-D: R2 = 0.991; MCPA: R2 = 0.999).
Conclusion: The results of the present study indicate that the synthesized nano-adsorbent can be used to remove phenoxic herbicides from agricultural runoff as well as water sources contaminated with the studied herbicides.

The impact of environmental pollutants emission (carbon dioxide) on life expectancy of men and women in Iran
Moslem Ansarinasab, Najmeh Bidmal,
Volume 14, Issue 4 (3-2022)
Abstract
Background and Objective: Among greenhouse gases, CO2 has a crucial role; thus, its impact on health indicators such as life expectancy is of great importance. Hence, one of the most important challenges in the health sector has been the impact of the environmental pollutants emission, namely CO2, on life expectancy of men and women.
Materials and Methods: This is a descriptive-analytical and applied design with the health economics approach. The present paper examined the impact of pollutant emissions, namely CO2, per capita income, death rate and birth rate, separately on Iranians’ life expectancy. This analysis was conducted using Quantile regression with EViews10 software during the period 1960 - 2019. In this study, first, the impact of pollutant emissions on life expectancy of all Iranians was calculated. Then, the impact of CO2 on life expectancy of Iranian men and women in different quantiles was estimated.
Results: The results confirm the impact of carbon dioxide emissions per capita on total life expectancy was -0.133 and the impact of this pollutant emission on life expectancy obtained -0.170 and -0.127 for men and women, respectively. Both effects were estimated as negative and significant. This effect on life expectancy of men was 0.43% higher than that of women. Furthermore, the impact of death on life expectancy was negative, while the effect of per capita income on life expectancy was positive. Also, birth rate had a positive impact on women's life expectancy, whereas, it showed a negative impact on men.
Conclusion: The study revealed that CO2 emissions had a negative impact on total life expectancy of both men and women. Thus, in order to increase life expectancy in Iran, pollutants emission, namely CO2, should be controlled. These results can be a good guide to decision makers and macro-policy makers in Iran to control environmental pollutants to increase life expectancy.
 

Comprehensive economic evaluation of municipal waste management and its sensitivity analysis: a case study in Karaj
Seyyed Shahram Naghibzadeh, Mazaher Moeinaddini, Mehdi Zafaranieh,
Volume 16, Issue 3 (12-2023)
Abstract
Background and Objective: The economic evaluation is a tool for decision-making based on data that helps to select and prioritize waste management components and their implementation based on economic criteria. The purpose of this study was a comprehensive economic evaluation of the waste management components by life cycle costing assessment (LCC) , Net Present Value index (NPV), and Internal Rate of Return (IRR).
Materials and Methods: The cost of each waste management component, was calculated by LCC for one tonne of waste in. The efficiency of each waste management component was obtained using the NPV and IRR indicators.
Results: The results showed that recycling with 260%, and then composting with 40%, have the highest economic returns and the ability to return capital. The sensitivity analysis showed the profitability of these two processes despite the changes of ±30% in the influential calculation parameters.
Conclusion: In this study, comprehensive economic evaluation showed that using LCC, NPV, and IRR with their sensitivity analysis, simultaneity can have an important role in waste management decision-making. 
 

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