The impact of municipal waste disposal of heavy metals on environmental pollution: A case study for Tonekabon, Iran

Azizpour, Aziz,Azarafza, Mohammad,Akgun, Haluk Techno-Press 2020 Advances in environmental research Vol.9 No.3

Municipal solid waste disposal is considered as one of the most important risks for environmental contamination which necessitates the development of strategies to reduce destructive consequences on the ecosystem as related especially to heavy metal accumulation. This study investigates heavy metal (i.e., As, Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn) accumulation in the Tonekabon region, NW of Iran that is related to city waste disposal and evaluates the environmental impact in the Caspian Sea coastal region. For this purpose, after performing field studies and collecting 50 soil specimens from 5 sites of the study area, geochemical tests (i.e., inductively coupled plasma mass spectrometry, atomic absorption spectroscopy and x-ray fluorescence) were conducted on the soil specimens collected from the 5 sites (named as Sites A1, A2, A3, A4 and A5) and the results were used to estimate the pollution indices (i.e., geo-accumulation index, normalized enrichment factor, contamination factor, and pollution load index). The obtained indices were utilized to assess the eco-toxicological risk level in the landfill site which indicated that the city has been severely contaminated by Cu, Mn, Ni, Pb and Zn. These levels have been developed along the stream towards the nearshore areas indicating uptake of soil degradation. The heavy metal contamination was classified to range from unpolluted to highly polluted, which indicated serious heavy metal pollution in the study area as related to municipal solid waste disposal in Tonekabon.

Evaluation of surface residual stresses in HVOF sprayed WC-12Co coatings by XRD and ED-hole drilling

M. Jalali Azizpour,S. Nourouzi 대한기계학회 2013 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.27 No.9

Thermally sprayed coatings are inherently associated with residual stresses in the coatings. These stresses have a noticeable effect on the physical and mechanical properties of coatings. The high speed hole drilling method is widely used to measure the residual stress. Due to the nature of the thermally sprayed coatings, the application of this method for WC/Co coatings has some limitations. In the current study, WC-12Co coatings were deposited using HVOF thermal spraying. The electro discharge hole drilling method was developed to measure the through thickness residual stress in WC-Co thermally sprayed coatings. Morphological studies were conducted using optical microscopy and scanning electron microscopy (SEM) to evaluate the powder and coating characteristics. The sin2ψ method was used to evaluate the surface residual stress by means of XRD. The residual stress at the surface using EDM and XRD was approximately -32.54 MPa and -40.6 MPa respectively. The experimental results reveal that the stress curves are not uniform through the coating thickness. It has been found that the mean residual stress is of approximately -126 MPa. Obtained results are in good agreement with the reported values from literatures. The developed method confirms the feasibility of residual stresses measurement for HVOF thermally sprayed WC-Co coatings.

Education based on the health belief model to improve the level of physical activity

( Masoud Khodaveisi ),( Bahman Azizpour ),( Ali Jadidi ),( Younes Mohammadi ) 한국운동영양학회 2021 Physical Activity and Nutrition (Phys Act Nutr) Vol.25 No.4

[Purpose] This study aimed to investigate the effect of education based on the health belief model on the physical activity of the staff of the University of Medical Sciences. [Methods] This semi-experimental study was conducted on 130 university staff aged 25-50 years from the Hamadan University of Medical Sciences. Inclusion criteria were having at least 1 year of work experience, lack of acute and chronic physical and mental illnesses, and not using drugs that affect physical activity. The samples were randomly divided into two groups. The experimental group received three training sessions based on the health belief model. Before and 2 months after training, the control and experimental groups were evaluated via the following questionnaires: (1) demographic information questionnaire, (2) Health Belief Model Questionnaire, and (3) International Physical Activity Questionnaire. Finally, data were analyzed statistically. [Results] The training process resulted in a significant increase in the mean scores of the health belief model constructs in the experimental group, but changes in the control group were not significant. Self-efficacy was the strongest predictor of physical activity. [Conclusion] The health belief model is a useful model for improving individuals' understanding of the benefits of physical activity.

Temporal and Spatial Distribution of Invasive Ctenophore Mnemiopsis leidyi in the Southern Part of the Caspian Sea from 2019 to 2020

Rahnama Haratbarr Reza,Azizpour Jafar,Manbohi Ahmad,Darvish Bastami Kazem,Hamzehpour Ali,Mehdinia Ali,Taheri Mehrshad 한국해양과학기술원 2024 Ocean science journal Vol.59 No.2

We investigated the abundance and distribution of the invasive ctenophore, Mnemiopsis leidyi, at fi ve transects in the southern part of the Caspian Sea for four seasons from December 2019 to August 2020. M. leidyi was found in all transects and seasons. The maximum temperature was around 27.5 °C in summer. The highest abundance and biomass of M. leidyi were found in the T 5 S 1 (Larim transect) and T 2 S 1 (Kiashahr transect) stations in summer (120 ± 22 ind m −3 and 279 ± 46 mg m −3 ) and the lowest in T 1 S 3 and T 1 S 2 stations (Lisar transect) in winter (3 ± 1 ind m −3 and 0.04 ± 0.01 mg m −3 ), respectively. Furthermore, the maximum average of abundance and biomass of M. leidyi were observed in Larim and Kiashahr transects (106 ± 15 ind m −3 and 242 ± 33 mg m −3 ) and the minimum in Lisar transect (4 ± 0.6 ind m −3 and 0.05 ± 0.01 mg m −3 ) respectively. Also, the body lengths that ranged between 0 and 5 mm were the most frequently observed. The highest total abundance and biomass of the M. leidyi were observed in summer (1033 ind m −3 and 2923 mg m −3 ) and the lowest in winter (122 ind m −3 and 22.09 mg m −3 ), respectively. The results of the DistLM showed that the distribution and abundance of M. leidyi in the south of the Caspian Sea are highly related to NO 3− and PO 4 3− and to a lesser extent to temperature and Sio 2 .

Enhancement of supercritical carbon dioxide solubility models using molecular simulation data

Hojatollah Moradi,Nariman Rezamandi,Hedayat Azizpour,Hossein Bahmanyar,Kamran Keynejad,Zahra Nasrollahi 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.3

Supercritical carbon dioxide (SC-CO2) has been used in a broad range of industrial applications due to its unique properties, which underlines the importance of understanding its exact behavior under different operating conditions. In this study, the solubility parameter (SP) of SC-CO2 was calculated using molecular dynamics simulation at varying temperature and pressure and different concentrations of methanol as a co-solvent. The obtained simulation results were used to create a model for solubility parameter using response surface methodology (RSM). These data were then used to improve three available empirical correlations of SC-CO2’s solubility parameter. The resulting equations were vastly superior in predicting the solubility parameter with an average coefficient of determination of 96.33%.

Progressive Collapse Resistance of Bolted Extended End-Plate Moment Connections

Samad Barmaki,Mohammad R. Sheidaii,Omid Azizpour 한국강구조학회 2020 International Journal of Steel Structures Vol.20 No.4

When a progressive collapse occurs due to sudden column removal, the moment connections must have adequate strength and be able to bridge over the damaged element. The present study comprehensively investigates the behavior of eight diff erent types of extended end-plate beam-to-column connections against progressive collapse. The proper fi nite element models have been extended to assess the behavior of these bolted connections under a sudden column removal scenario. Specimens were checked by nonlinear analysis method. The fracture modes, Von-Mises stresses, vertical load–displacement and load factor–displacement curves, load transferal mechanisms, and other analytical results comparative were reported in detail and discussed for various investigated beam-to-column connections. The analysis results revealed that the overall failure of the samples occurred in the connection region under the catenary action mode at large displacements. Also, the results were verifi ed with available experimental data. Among all investigated connections, the highest stresses could be applied to the sixteen-bolt stiff ened connection, and this sample had the most excellent behavior. In the design of buildings exposed to unusual loads due to progressive collapse, the signifi cant axial force created in the connections should be considered in the design stages of these elements. Also, it is recommended that at least three rows of bolts are embedded in the bottom area of end-plate connections when the structure is at the risk of progressive collapse.