خيارات البحث
النتائج 21 - 30 من 4,896
Performance Comparison of Predictive Controllers in Optimal and Stable Operation of Wastewater Treatment Plants
2019
Hasanlou, H. | Torabian, A. | Mehrdadi, N. | Kosari, A. R. | Aminzadeh, B.
Any proper operation could be translated as a constrained optimization problem inside a WWTP, whose nonlinear behavior renders its control problems quite attractive for performance of multivariable optimization–based control technique algorithms, such as NMPC. The main advantage of this control technique lies in its ability to handle model nonlinearity as well as various types of constraints on the actuators and state variables. The current study presents the process of BSM1 building, step by step, proposing appropriate numerical methods are creating the simulation model in MATLAB environment. It also makes a detailed comparison of the proposed NMPC with five recent predictive control schemes, namely LMPC, hierarchical MPC+ff, EMPC, and MPC+fuzzy, along with the default PI. The performance of predictive control schemes is much better than the default PI; however, something of highest importance is the ability to use the proposed control scheme in real systems, for a real application faces several limitations, especially in terms of the equipment. Finally, in order to compare predictive controllers, it is necessary to determine the same conditions so that results from more days can be used, and, if needed, more than 28 days have to be simulated. MOI index can help determine which of the proposed control scheme is really applicable.
اظهر المزيد [+] اقل [-]Residues and Dissipation Kinetics of Two Imidacloprid Nanoformulations on Bean (Phaseolus vulgaris L.) under Field Conditions
2019
Memarizadeh, N. | Ghadamyari, M. | Talebi, K. | Torabi, E. | Adeli, M. | Jalalipour, R.
The current study investigates the dissipation kinetics of two imidacloprid (IMI) nanoformulations (entitled: Nano-IMI and Nano-IMI/TiO2) on common bean (Phaseolus vulgaris) seeds under field conditions and compares them with 35% Suspension Concentrate (SC) commercial formulation. To do so, it sprays P. vulgaris plants at 30 and 60 g/ha within green bean stage, sampling them during the 14-day period after the treatment. Following extraction and quantification of IMI residues, dissipation data have been fitted to simple-first order kinetic model (SFOK) and to first-order double-exponential decay (FODED) models, with 50% and 90% dissipation times (DT50 and DT90, respectively) assessed along the pre-harvest interval (PHI). With the exception of Nano-IMI at 60 g/ha, other decline curves are best fitted to the FODED model. In general, dissipation is faster for Nano-IMI (at 30 g/ha: DT50 = 1.09 days, DT90 = 4.30 days, PHI = 1.23 days; at 60 g/ha: DT50 = 1.29 days, DT90 = 4.29 days, PHI = 2.95 days) and Nano-IMI/TiO2 (at 30 g/ha: DT50 = 1.15 days, DT90 = 4.40 days, PHI = 1.08 days; at 60 g/ha: DT50 = 0.86 days, DT90 = 4.92 days, PHI = 3.02 days), compared to 35% SC (at 30 g/ha: DT50 = 1.58, DT90 = 6.45, PHI = 1.93; at 60 g/ha: DT50 = 1.58 days, DT90 = 14.50 days, PHI = 5.37 days). These results suggest the suitability of Nano-IMI and Nano-IMI/TiO2 application at both rates in terms of their residues on P. vulgaris seeds.
اظهر المزيد [+] اقل [-]Evaluation of Catalytic Effects of Metal Oxide Nanoparticles on Pyrolysis of Used Lubricating Oil
2019
Alavi, S. E. | Abdoli, M. A. | Khorasheh, F. | Bayandori Moghaddam, A.
Pyrolysis is an applicable method that has been widely used to recover hydrocarbons from Used Lubricating Oil (ULO). However, large-scale application of this approach has been limited by its noticeably energy and time consuming nature. In the present research, it has been attempted to modify the energy and time requirements of ULO pyrolysis using the catalytic effects of metal oxide nanoparticles (NPs). The impacts of γ-Al2O3, γ-Fe2O3 and ZnO NPs on the kinetic features of ULO pyrolysis were studied using thermogravimetric analysis (TGA). The kinetic parameters of the pyrolysis process were calculated based on Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozava (FWO) models. The activation energy of virgin ULO pyrolysis had been calculated to be 161.505 and 162.087 kJ/mol using KAS and FWO models, respectively. However, in the present work, utilization of γ-Fe2O3 NPs significantly reduced the activation energy of ULO pyrolysis to 133.511 and 138.289 kJ/mol through KAS and FWO models, respectively. The catalytic effect of ZnO NPs was not as noticeable as that of γ-Fe2O3 NPs, resulting in activation energies of 155.568 and 158.501 kJ/mol using KAS and FWO models, respectively. Moreover, based on the results of this study, γ-Al2O3 NPs had no significant impact on the kinetics of ULO pyrolysis.
اظهر المزيد [+] اقل [-]Convenient and Efficient Elimination of Heavy Metals from Wastewater Using Smart Pouch with Biomaterial
2019
Malik, R. | Saini, N. | Ahlawat, S. | Singhal, S. | Lata, S.
A newly developed Smart Pouch with enclosed biomaterial (Aloe vera and coconut husk powder) has been experimented for elimination of heavy metals i.e. (Pb2+, Cu2+, Ni2+ and Zn2+) from wastewater. The effect of concentration, pH, temperature, contact duration etc. was investigated using batch experiments which resulted that the Pouch may be accepted for convenient, efficient and low-cost accumulation of several heavy metals simultaneously from waste water. The maximum Pb removal was 99.99%, 93.21% for Cu, and for Ni, it was 91.97% whereas for Zn, 86.41% was obtained and also, the uptake capacity of pouch was quite sensitive towards initial metal concentration in the studied range of 10-200mg/L present in wastewater. The findings were further interpreted by quantum chemical study as theoretical support, various adsorption isotherms, FTIR, SEM, XRD, and physiochemical properties of metal ions to justify the synergized performance of new Pouch. A good correlation was found between experimental methods and theoretical findings.
اظهر المزيد [+] اقل [-]Study of seasonal and spatial variability among Benzene, Toluene, and p-Xylene (BTp-X) in ambient air of Delhi, India
2019
Garg, A. | Gupta, N.C. | Tyagi, S.K.
This study was carried out to analyze the variations of Benzene, Toluene, and para- Xylene (BTp-X) present in the urban air of Delhi. These pollutants can enter into the human body through various pathways like inhalation, oral and dermal exposure posing adverse effects on human health. Keeping in view of the above facts, six different locations of Delhi were selected for the study during summer and winter seasons (2016-2017). The concentrations of BTp-X on online continuous monitoring system were analyzed by chromatographic separation in the gaseous phase followed by their detection using a Photo Ionization Detector (PID). The concentrations of BTp-X were found maximum at a high traffic intersection area as 68.35±48.26 µg/m3 and 86.84±32.55 µg/m3 in summer and winter seasons respectively and minimum at a residential area as 4.34±2.48 µg/m3 and 15.42±9.8 µg/m3 in summer and winter seasons respectively. The average BTp-X concentrations of summer and winter seasons were found as 9.88, 20.68, 28.52, 49.75, 64.04, and 77.59 µg/m3 at residential, institutional, commercial, low traffic intersection, moderate traffic intersection and high traffic intersection areas respectively. Clearly, it has been found that the concentrations of these compounds were more on the traffic areas indicating that the vehicles are the major emission source. Hence, it may be concluded that the number of vehicles along with the high traffic congestion on the city streets and roads results in more accumulation of aromatic compounds and deteriorate the urban air quality.
اظهر المزيد [+] اقل [-]Influence of Copper Oxide Nanoparticle on Hematology and Plasma Biochemistry of Caspian Trout (Salmo trutta caspius), Following Acute and Chronic Exposure
2019
Kaviani, E. F. | Naeemi, A. S. | Salehzadeh, A.
The Caspian trout is an endangered and quite vulnerable fish, considered for a natural protection program in the southern area of the Caspian Sea. Copper oxide nanoparticles (CuO-NPs) are toxic substances, which induce oxidative stress, not to mention other pathophysiological states. The toxicity of nanoparticles on fish needs more characterization for short- and long-term effects. Thus, the present paper examines the acute and chronic effects of CuO-NPs on hematology and plasma biochemistry of juvenile Caspian trout. After determining the lethal concentrations (LC50), juvenile Caspian trout is exposed to 0.1 LC5096 CuO-NPs for 28 days in three replicates. The blood samples are then collected from fish after 24, 48, 72, and 96 hours as well as 1, 2, 3, and 4 weeks of exposure to the CuO-NPsto deal with short- and long-term effects, respectively. Analysis of these samples shows that some hematological factors like hemoglobin (Hb), red blood cells (RBC), and hematocrit (Hct) are significantly increased after acute exposure, compared to the control group (p<0.05). The number of white blood cells (WBC), neutrophilis, and monocytes are also increased after acute and chronic exposure with significant differences (p< 0.05). Furthermore, the levels of lactate dehydrogenase after acute and alkaline phosphatase along with aspartate aminotransferase after acute and chronic exposure are significantly increased (p<0.05). Thus, results indicate that the presence of even a tiny amount of CuO-NPs can affect most haematological and metabolic enzymes of the Caspian trout in the short and long-term exposure. It is therefore essential to prevent these nanomaterials from entering the aquatic environment.
اظهر المزيد [+] اقل [-]Verification of IVE Model for SAIPA Co. Fleet Emission
2019
Alipourmohajer, Sh. | Rashidi, Y. | Atabi, F.
To determine the amount of air pollutants, produced by Iranian automakers, and compare it with old and retrofitted vehicles have become one of the important tools of urban management. The present research uses International Vehicle Emission (IVE) modeling software in order to verify SAIPA Co. fleet emissions, based on Euro 4 emission standard (SAIPA Co. recognized as a superior Iranian brand in vehicle industry). There has been attempts to determine pollutant emission from Saipa Co.-manufactured cars in the city of Tehran, in accordance with Tehran Driving Cycle along with modeling and lab results which have over 90% conformity with modeling and lab results of New European Driving Cycle. According to ISQI’s 100,000-km test results, the amount of CO2 emission modeling from X100 and Tiba2’s has been about 160 gr/km, which has been within the range, whereas the modeled CO2 emission rate has been 232 gr/km in TDC, i.e., 1.5 times more than laboratory test, due to different driving cycle usage. Significant differences between the values obtained in the emission lab and modeling at New European Driving Cycle, Tehran Driving Cycle, and Tehran Air Quality Control Company report, indicate that relying on hypothetical situation leads to inapplicable emissions value from light vehicles.
اظهر المزيد [+] اقل [-]Monitoring of SO2 column concentration over Iran using satellite-based observations during 2005-2016
2019
Salmabadi, H. | Saeedi, M.
For the first time, sulfur dioxide concentration was monitored between 2005 and 2016 over Iran which is among the countries with a high SO2 emission rate in the world. To that end, SO2 column concentration at Planetary Boundary Layer (PBL) from Ozone Monitoring Instrument (OMI) was analyzed. OMI is a sensor onboard the Aura satellite which can measure daily SO2 concentration on the global scale. From OMI maps, 19 notable SO2 hotspots were detected over Iran. The results indicate that the most elevated level of SO2 among these 19 hotspots belong to Khark Island and Asaluye in Bushehr province, southwest of Iran. Annual trend analysis shows that SO2 concentration has been slightly augmented during 2005-2016 over this country. Distribution analysis of SO2 concentration over Iran showed that the most polluted provinces are Bushehr, Khuzestan and Ilam lied in the southwest of Iran. On the contrary, the lowest level of SO2 has observed over northwest of Iran at West and East Azerbaijan and Ardabil provinces. The correlation coefficient between total energy production in Iran and SO2 concentration from 2005 to 2016 is as high as ~0.7. Hence, it can be derived that energy production, most notably production of crude oil, plays a pivotal role in SO2 concentration over Iran.
اظهر المزيد [+] اقل [-]Degradation of Hydrocarbons and Lignin-like compounds by Alcaligenes sp. strain 3k isolated from Ilorin
2019
Adetitun, D. O. | Fathepure, B. | Hugh, H. | Kolawole, O. M. | Olayemi, A. B.
The primary goal of this study was to isolate hydrocarbon-degrading organisms and assess their ability to bioremediate petroleum-contaminated soil and water. Nigeria is one of the major oil producing countries and petroleum contamination is widespread in agricultural soil. Alcaligenes sp. strain 3k was isolated from a kerosene-polluted soil in Ilorin, Nigeria. We also assessed its ability to degrade plant lignin, as lignin is a complex aromatic heteropolymer commonly found in soil and aquifer environment. Strain 3k was originally grown on mineral salts medium with kerosene as a sole energy and carbon source. The capacity of the isolate to degrade both aromatic, aliphatic hydrocarbons and lignin-like compounds was tested. Among the tested compounds, the organism utilized kerosene, hexadecane, cyclohexane, phenol and benzoate as the sole sources of carbon. In addition, strain 3k also degraded various lignocellulose compounds as the sole source of carbon. However, hexane, benzene, toluene, ethylbenzene and xylene were not metabolized. Our study demonstrates that soil organisms like Alcaligenes could play important role in the reclamation of petroleum-contaminated soil and water. Utilization capacity of lignin as the sole carbon source suggest that these organisms can survive on plant detritus and also have the ability to degrade hydrocarbons upon accidental or deliberate contamination of agricultural soil and water.
اظهر المزيد [+] اقل [-]The Evaluation of Tropospheric Ozone Formation in the Downwind of the South Pars Industrial Zone
2019
Moradzadeh, M. | Ashrafi, k. | Shafiepour-Motlagh, M.
Hydrocarbon Processing Industries (HPIs) emit large amounts of highly reactive hydrocarbons and Nitrogen Oxides to the atmosphere. Such simultaneous emissions of ozone precursors result in rapid and high yields ozone (O3) formation downwind. The climate of the Middle East has been shown to be favorable for O3 formation in summer. There are also vast activities in processing oil and gas in this region. This study aimed to investigate the influence of HPIs located in the Middle East on ozone formation. We chose the South Pars Zone (SPZ) located in the coastal area of the Persian Gulf with concentrated HPIs as a case study. To do this, after developing an emission inventory for O3 precursors, we used OZIPR, a Lagrangian photochemical model, coupled with SAPRC-07 chemical mechanism to describe the effects of HIPs on ozone formation in the SPZ and downwind area from June to August of (2017). Results indicate that the SPZ has a far-reaching and wide-ranging impact on O3 formation in downwind areas and an area at a distance of 300 km can be affected profoundly (Average 0.06 ppm and maximum increase 0.24 ppm). Given the large numbers of HPIs located in the Middle East, we predict that the transport of O3 and its precursors from this region play an important role in the ozone air pollution in a much wider area and the role of these industries should be taken into account for regional and interregional ozone concentration modeling.
اظهر المزيد [+] اقل [-]