مهندس علیرضا رحمتی

Climate change and the increase in the population of cities have caused many environmental problems. The decrease in the function of urban agriculture has also made the efficiency of green infrastructures and their ecosystem services naturally inefficient. The purpose of this research is to provide a model of sustainable cultivation of productive plants in cities to moderate the effects of climate change and land use in District 22 of Tehran Municipality. In this study, the land use map of 2000 and 2020 was made using Landsat satellite images. Then, the LCM model was used to predict land use changes in 2050. RCP scenarios were simulated to investigate climate change. 4 criteria and 21 sub-criteria and the best-worst method (BWM) and the cumulative ratio evaluation method (ARAS) were used to obtain the weight of the selection criteria of fruitful plants. Based on the obtained results, it was determined that green and agricultural areas will change by 12% and -4.5% from 2000 to 2050, respectively. The risk of climate change also predicted a warming of 1.32 to 2.27 degrees. Based on this, the suitability map of the region for urban agriculture and the area of suitability classes according to the criterion of compatibility with the environmental conditions of the region (with a weight of 0.472), ecological conditions (0.268), compatibility with the urban environment (with a weight of 0.179) and aesthetic-cognitive (with a weight of 0.081) was prepared. According to the opinion of experts, fruitful plant species such as Wild Pistachio, Christs thorn, Wild almond, Pistachio, Olive have found the highest priority for cultivation in large and medium urban scale. About 40% of the area has good and high suitability for planting these plants.

The present paper aims at studying bio-capacity and ecological footprint of five continents and position of Iran in this regard. We used ecological global footprint network in 2021. In terms of bio-capacity, Asia, Africa, Europe, Americas and Oceania have the highest to lowest bio-capacity respectively. Asia with 3,278,060,962 hectares has the top rank and Oceania enjoys the fifth rank. Ecological footprint indicates that Asia, Africa, Europe, Americas and Oceania have left the highest to lowest ecological footprint respectively. Asia with 10,565,813,892 hectares has the top rank and Oceania with 180,360,560 hectares enjoys the lowest rank. Americas leave ecological footprint 5.03 times more that the planetary bio-capacity followed by Oceania (4.45), Europe (2.97) and Asia (1.52) respectively. Africa just enjoys 0.77 of its bio-capacity. Carbon footprint has left the highest footprint in Americas, Oceania, Europe and Asia respectively. With 60,400,000 global hectares, Iran ranks 36th in terms of total bio-capacity among all countries worldwide while in terms of ecological footprint and with 262,000,000 global hectares, Iran ranks 16th. Iranian bio-capacity per person ranks 130th with 0.7 global hectares while its ecological footprint per person is 3.2 global hectares ranking it 78th among all countries. As such, Iran currently encounters 333% of bio deficit.

Nowadays, it is a common idea to use decorative concrete panels as an alternative to natural stone. Graphic concrete is one of the different types of decorative concrete using the exposed-aggregate method. Considering that there has been no research for graphic concrete production in Iran so far, the aim of this research is to localize and simplify the method for the first time. For this purpose, concrete samples with 435 kg/m3 and 500 kg /m3 Portland cement and water to cement ratio of 0.40 and 0.45 have been produced using natural sand as aggregate. Also, superplasticizer with dosage of 0.35 % and air-entraining admixture with dosage of 0.02% have been used. Concrete specimens were tested in terms of visual criteria, compressive strengths and water absorption in 28 days in accordance with the requirements of Iran National Standard 12038. The results showed that samples with the water to cement ratio of 0.40, which were produced without using of superplasticizer and air-entraining admixture, due to low workability of the mixture, are not in good condition in terms of compressibility. Also low workability, in addition to disrupting the designs printed on the membrane, causes many holes on the concrete surface after leaving the mold, which is visually rejected. Despite the positive effects of air entraining admixture on workability, plastic viscosity and visual criteria, this type of admixture reduces the compressive strength by 30 to 35% and increases water absorption, which is not recommended. Finally, mixture design with 500 kg/m3 of cement, water to cement ratio of 0.40 and 0.45, which were produced using superplasticizer with 28-day compressive strength of 54.6 and 52.5 MPa and Water absorption of 3.25% and 3.50% while meeting all requirements are suitable for production of graphic concrete decorative panels.

Arak is one of the eight most polluted cities in Iran, whose pollution is mainly due to the activities of various industries located in the city or its suburbs. Using air pollution modeling it would be possible to estimate the effect of emissions of suspended particles and gases from the activities of various industries on the local environment. This study is an attempt to investigate the impact of existing and under construction industries in Arak on the air quality of the city using the ADMS model as a widely used and trusted model of the Department of Environment (DoE).

Because the main sources of air pollution in Arak are of focal type, in modeling air pollution, 17 large industries (including 98 chimneys) located in the city were considered as pollution points. In addition to the emission data, the geometrical data of the chimneys including the height and diameter of their opening and the temperature of the exhaust air were also included in the model. To validate the model outputs, the measurement values of the environmental stations were compared with the values estimated by the modeling using Pearson linear correlation coefficient.

The results showed that the concentration of CO, SO2, and NO2 in all stations was within the permissible level announced by the DoE. The dispersion of suspended particles (contour lines) in the city was to the west and southwest and up to a radius of 3 km in the prevailing and semi-prevailing wind direction. This for Shazand was to the west up to a radius of 1 km in the prevailing wind direction and to the southwest up to 5 km in the direction of semi- prevailing wind until reaching the background concentration of 19.1 μg. Accumulation of SO2 contour lines in Shazand pollution center was observed up to a radius of 7 km in the west direction and up to a radius of 10 km in the southwest direction. The accumulation of NO2 contour lines was the same as NO2. The radius of impact of CO gas was extended from Arak to Shazand. Accumulation of CO contour lines in Arak was up to a radius of 5 km in the direction of west and southwest. The accumulation of H2S contour lines in Shazand was up to a radius of 5 km towards the directions of west, southeast, and southwest. In general, the difference between the sampling and modeling results indicated the pollution sources that were not observed in the model and were beyond those emitted from the factories. In most stations, the modeled and directly monitored SO2 concentrations were not much different and the correlation coefficient of the data was high, indicating the accuracy of the calculations and the prominent role of industries in the emission of this gaseous pollutant. Also, in most stations, the results of environmental measurement of NO2 were less than the modeled values, revealing that the industries had a greater share in the emission of this gas. The overestimate of this emission may probably be due to the inclusion of the under construction industries in the model. The environmental concentration of CO in all stations was higher than the modeled values. Industries have a small share in the pollution load of this pollutant while in urban areas, the concentration of CO depends on the mobile sources and traffic load.

In general, the pollution levels of the city showed that the center of pollution was in the southeast of Arak and in the complex of the refinery, petrochemical company, and thermal power plant. According to the overlaid contours of emissions, a number of points (14 points) that were closest to the pollution centers were proposed as critical stations, two points as control stations, and 4 points as the stations exposed to pollution in each period.

In any type of geographic data analysis defining the primary unit has direct effect on the results. The key point in spatial studies is the exact definition of areal units. The necessity of defining the basic unit of study is that for instance if once we examine the relationship between income and crime rate in the neighborhood unit and again in the level of urban area, different results will be obtained. This problem originates from the fact that raw data (e.g. census) are shown in the census block format. So we have to aggregate this data into neighborhood units and urban areas or any other basic unit for our study. Since the choice of these basic units does not have any rule and is arbitrary, different results will be obtained. In fact results of statistical analysis are not independent of the scale at which analysis has been done. This problem was first identified by Gehlke and Biehlin as modifiable areal unit problem (MAUP). The purpose of this study is to identify the basic areal units which make the least bias in raw data after data aggregation in the unit. We have applied a comparative research method and layers of census blocks are utilized for statistical analysis. In this article, we have selected three basic units based on urban network, urban locality and fishnet as well as using twenty demographic indicators and measures of central dispersion and correlation to examine the effect of MAUP. The results indicate that rectangular base unit is less affected by the MAUP.

The objective of this paper is to produce Rice husk ash based Geopolymer concrete brick without Portland cement. Pollution of the cement industry produces 8% of the world's greenhouse gases and pollutants. Today, the replacement of aluminosilicate pozzolans, known as supplementary cementitious materials (SCMs), play a significant role in reducing the production and use of Portland cement. In this research, samples of geopolymer concrete with 350 kg/m3 and 400 kg/m3 of rice husk ash, Alkali activator solution consisting of 10 and 16 M sodium hydroxide in combination with sodium silicate solution, fine aggregates and additives were produced and cured at 60 and 90°C. In all 8 mixing designs, water to RHA ratio is 0,42 and alkaline solution to RHA ratio is 0,45. Finally, the specimens were tested for compressive strength according to the Iranian national standard 1608-3 at the ages of 3, 7 and 28 days and according to the Iranian national standard 14733 in 28 days for water absorption. The results showed that with increasing the amount of RHA and molarity of Alkali activator solution, the workability of concrete decreases and the adhesion and viscosity of concrete increases. The highest Compressive Strength of 100mm Cube after 28 days was 29.2 MPa and it is related to the specimens with 400 kg/m3 of RHA and 16 M Alkali solution, which was Heat cured at 90°C. By reducing the amount of RHA to 350 kg/m3 and preserving other components, the compressive strength decreased by 42% to 16.8 MPa, which indicates the significant effect of these parameters on the mechanical properties of the produced concrete. The lowest percentage of water absorption was 3,46 % and related to the specimens with 400 kg/m3 of RHA and 16 M alkaline solution. By reducing the RHA content to 350 kg/m3 and preserving other components, the percentage of water absorption increased to 5,23 %.

Air pollution is one of the most important environmental problems that have become a serious threat to human health in recent years with the development of societies and industrialization. Ammonia is one of the most important pollutants. The spray tower is a wet scrubber used for ammonia purification, so the present study was conducted to investigate the change of physical parameters using a 2500µm nozzle and acidic water solution on ammonia removal in a spray tower under standard conditions.

In the present study, the amount of ammonia gas removal was investigated by changing parameters such as air pressure, pollutant density and number of nozzles, using a washing tower at two inlet and outlet locations and a total of 162 test times with three replicates. Data were analyzed by One-Way ANOVA in SPSS-21 software.

The results showed that increasing the number of nozzles and the spray pressure of the spray tower significantly increased (p<0.05) and increasing the inlet load significantly decreased the efficiency (p<0.05) of ammonia gas removal efficiency.

By increasing the number of nozzles, the pressure of the dilute sulfuric acid solution and reducing the density of the pollutant gas, good efficiency can be achieved in removing ammonia gas from the air stream using spray tower.

The increase in the metropolitan population and, consequently, the increase in traffic, the urgent need to reduce pollution and traffic, and so on, have led to the expansion of the metro lines. In this regard, it is important to survey the physical and mental health of workers in these fields, because of its impact on their behavior, performance and productivity.

The present study was a cross-sectional descriptive-analytical study with the 176 shift workers in a tunneling workshop with a mean age of 28.7±4.8. A general health questionnaire (GHQ-28) was used to assess the general health status of these workers and demographic and occupational information were added to collect the required data. The total cut-off point was 22 and a score of 6 was considered for each scale. As a result, score above 6 on each scale and a total score above 22 on all four scales indicate the presence of disease symptoms in individuals. The results were tested by three statistical tests of independent t-test, one-way ANOVA and correlation test, using SPSS-21 software.

The results showed that according to the cut-off point, the prevalence of physical symptoms was 37%, anxiety and insomnia 24%, social dysfunction 57% and severe depression 11% and in total, 51% of workers had mental disorders. The factors of marriage/Single (p<0.03), Native/non-native (p<0.02), distance to home (p<0.001), level of education (p<0.03), work experience (p<0.05), Job scheduling (p<0.001), and job satisfaction (p<0.001), all had a significant effect on general health.

The results of this study showed that improving the working conditions of workers in tunnel construction operations such as providing job security, improving job satisfaction, modifying the work schedule especially eliminating permanent overnight work, continuing education and marriage is necessary.

Today SEA is one of the most important tools on which environmental considerations can be institutionalized in the planning system. In this regard, it is important to select the effect of scale jumps on the process of SEA. Therefore, in this study, with using the favor of spatial scale 1:250000 and satellite imagery ASTER and SRTM in the first order Persian Gulf and Omman sea watershed an attempt has been made to test whether SEA outputs are aligned with macro policies and to increase the scale in the spatial dimension. In this regard, first by inputting raw data of digital elevation model in Arc SWAT extension in Arc map software and processing their related calculations HRUs and then, introduce the 11 year climatic data to the SWAT model and implement (RUN) SWAT model at different spatial scales. The results showed that re-sizing the digital elevation model had a significant effect in the first order Persian Gulf and Omman sea watershed.

Workplace air quality is a very important factor in community health and is measured by measuring and evaluating airborne contaminants. One of these airborne pollutants is ammonia gas. Spray towers are important components of air pollution control. The aim of this study was to investigate the effects of using diluted sulfuric acid solution on the efficiency of ammonia removal in a spray tower.

In this study, the rate of ammonia removal from the air stream was measured using a spray tower in the laboratory, by changing the liquid pressure and nozzles and the inlet density. The volume of air flow used was 3737.82 l/min and the nozzle used was 20 microns in diameter, one, two and three, with dilute sulfuric acid solution. Data were analyzed by One-Way ANOVA and SPSS.21 software.

Increasing the number of nozzles and the spray pressure of the spray tower increased the spray removal efficiency and increasing the input load to the system reduces the elimination efficiency (P<0.05).

By increasing the number of nozzles and diluting the dilute sulfuric acid solution, it is possible to achieve proper performance in spray tower removal of ammonia gas.

Improving the quality and status of country’s environment through targeted research management is one of the most important goals of the research centers in this field. In this regard, administration and prioritizing the environmental research can play a significant role in achieving this goal. This paper uses the collected data from a research project called "Needs Assessment and Prioritization of the Research Institute of Environment and Sustainable Development", a systematic approach to identifying the research priorities. This process is based on five principles. These principles include beneficiaries participation, status analysis and needs assessment, identification of research bases, scoring the research bases, based on feasibility and attractiveness criterions and prioritization based on the highest agreement rates at the research institute (the Institute of Environment and Sustainable Development). The experts participating in this project were, 16.66% from Environmental Research Institute, 15.15% from department of Water and Soil, 13.63% from county departments, 9.09% from department of Marine Ecosystems, 54.4% from faculty members of universities and the rest of them, from the Environmental Protection Agency. In total, there are 346 research bases, 28 titles in ecology; 5 titles in science; 41 titles in environmental engineering and technology; 44 titles in environmental economics; 31 titles in environmental law; 108 titles in environmental management; 26 titles in natural science; 22 titles in social systems; 27 titles in Biological Safety and 14 titles in Environmental Technology. These research bases were analyzed by the experts and the most important research priorities were identified.

Polymer modified concrete (PMC) have been called by various names, such as latex modified concrete (LMC). LMC is defined as hydraulic cement combined at the time of mixing with organic polymers that are dispersed in water with aggregates. The improvements from adding polymer modifiers to concrete include increased bond strength, freezing-and-thawing resistance, abrasion resistance, flexural and tensile strengths, and reduced permeability and elastic modulus. A reduced elastic modulus might be useful considering the application of LMC as a bridge-deck overlay or repair surface. Concrete overlays have higher durability and life time compare to asphalt overlays. In this article the applications of concrete pavements and LMC overlays are discussed. Due to the fact that LMC overlays have not been used in any road construction projects in Iran, research needed to be done in order to produce the styrene butadiene latex used in LMC. The research and development group at Chimisazeh Armani successfully produced the SBR latex and placed a sample in Tehran-North High way project by following the guidelines given by ACI and FHWA. The result proved that LMC is a great choice as an bridge deck overlay.

One of the major factors that affect the employees' health and productivity in industries is the air quality of work environments. One of these pollutants is ammonia gas, which is very important from an economic and environmental points of view. Therefore, this study aimed to investigate the effect of using acidic water compound on the removal efficiency of air ammonia in a spray tower.

In this study, airflow was provided by variable ventilation and water pressure through a class electropump. The rate of ammonia removal from the air stream was investigated by a spray tower with changes in water pressure, inlet gas density, and number of nozzles. For this purpose, at different inlet densities, different liquid pressures and different nozzles with water washing liquid with 0.01 mM sulfuric acid were used as the washing liquid.

Increased number of nozzles from one to three had a significant effect on ammonia removal (P-Value = 0.021). Increase of the inlet ammonia gas density from 24.1 to 68 parts per million significantly reduced the efficiency (P-Value = 0.058). Increase of the spray pressure from 9 bar to 12 bar also significantly increased the removal of ammonia gas from the spray tower outlet (P-Value = 0.052).

Increased number of nozzles, increased spray pressure, and decreased density of the ammonia gas inlet gas will increase removal efficiency.