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Shokri M, Gogliettino AR, Hottowy P, Sher A, Litke AM, Chichilnisky EJ, Pequito S, Muratore D. Spike sorting in the presence of stimulation artifacts: a dynamical control systems approach. J Neural Eng 2024; 21:016022. [PMID: 38271715 PMCID: PMC10853761 DOI: 10.1088/1741-2552/ad228f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 11/08/2023] [Accepted: 01/25/2024] [Indexed: 01/27/2024]
Abstract
Objective. Bi-directional electronic neural interfaces, capable of both electrical recording and stimulation, communicate with the nervous system to permit precise calibration of electrical inputs by capturing the evoked neural responses. However, one significant challenge is that stimulation artifacts often mask the actual neural signals. To address this issue, we introduce a novel approach that employs dynamical control systems to detect and decipher electrically evoked neural activity despite the presence of electrical artifacts.Approach. Our proposed method leverages the unique spatiotemporal patterns of neural activity and electrical artifacts to distinguish and identify individual neural spikes. We designed distinctive dynamical models for both the stimulation artifact and each neuron observed during spontaneous neural activity. We can estimate which neurons were active by analyzing the recorded voltage responses across multiple electrodes post-stimulation. This technique also allows us to exclude signals from electrodes heavily affected by stimulation artifacts, such as the stimulating electrode itself, yet still accurately differentiate between evoked spikes and electrical artifacts.Main results. We applied our method to high-density multi-electrode recordings from the primate retina in anex vivosetup, using a grid of 512 electrodes. Through repeated electrical stimulations at varying amplitudes, we were able to construct activation curves for each neuron. The curves obtained with our method closely resembled those derived from manual spike sorting. Additionally, the stimulation thresholds we estimated strongly agreed with those determined through manual analysis, demonstrating high reliability (R2=0.951for human 1 andR2=0.944for human 2).Significance. Our method can effectively separate evoked neural spikes from stimulation artifacts by exploiting the distinct spatiotemporal propagation patterns captured by a dense, large-scale multi-electrode array. This technique holds promise for future applications in real-time closed-loop stimulation systems and for managing multi-channel stimulation strategies.
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Affiliation(s)
- Mohammad Shokri
- Delft Center for Systems and Control, Delft University of Technology, Delft 2628 CN, The Netherlands
| | - Alex R Gogliettino
- Neurosciences PhD Program, Stanford University, Stanford, CA 94305, United States of America
- Hansen Experimental Physics Laboratory, Stanford University, Stanford, CA 94305, United States of America
| | - Paweł Hottowy
- Faculty of Physics and Applied Computer Science, AGH University of Krakow, Krakow, Poland
| | - Alexander Sher
- Santa Cruz Institute for Particle Physics, University of California, Santa Cruz, CA, United States of America
| | - Alan M Litke
- Santa Cruz Institute for Particle Physics, University of California, Santa Cruz, CA, United States of America
| | - E J Chichilnisky
- Departments of Neurosurgery and Ophthalmology, Stanford University, Stanford, CA 94305, United States of America
| | - Sérgio Pequito
- Division of Systems and Control, Department of Information Technology, Uppsala University, 751 05 Uppsala, Sweden
| | - Dante Muratore
- Microelectronics Department, Delft University of Technology, Delft 2628 CN, The Netherlands
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Shokri M, Kibler KM, Hagglund C, Corrado A, Wang D, Beazley M, Wanielista M. Hydraulic and nutrient removal performance of vegetated filter strips with engineered infiltration media for treatment of roadway runoff. J Environ Manage 2021; 300:113747. [PMID: 34649328 DOI: 10.1016/j.jenvman.2021.113747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 09/10/2021] [Accepted: 09/11/2021] [Indexed: 06/13/2023]
Abstract
As a new strategy for treating excess nutrients in roadway runoff, a self-filtering roadway could be accomplished by including engineered infiltration media within a vegetated filter strip (VFS) located in the roadway shoulder. However, nutrient removal performance will depend on the design to effectively infiltrate roadway runoff and the capacity of subsurface media to sequester or remove nutrients from infiltrated runoff. The objective of this study is to test hydraulic and nutrient removal performance of a roadside VFS over varied rainfall-runoff event sizes and filter widths. Two identical 1:1 scale physical models of roadway shoulders and embankments, one containing engineered media (Treatment model) and the other without (Control model), were tested with simulated rainfall and runoff from 1- and 2-lane roadways. Overall, 32 paired hydraulic experiments and 28 paired nutrient removal experiments were completed to assess performance across frequent and extreme rainfall-runoff events. The results indicate that scalability of performance with filter width varied by parameter. Runoff generation scaled predictably with filter width, as runoff generated close to the pavement and total infiltration increased with filter length. A 6 m-wide VFS containing the engineered media infiltrated all rainfall-runoff except during the most extreme storm events (1-h storms of 76.2 mm and 50.8 mm), where respectively 35% and 22% of rainfall-runoff did not infiltrate and left the system as surface runoff. A majority of phosphorus was retained within a 1.5 m filter while nitrate removal was not observed until 6 m. The Treatment model strongly outperformed the Control model with respect to nitrate (arithmetic mean ± standard deviation of 94 ± 6% reduction vs. 23 ± 64% increase, p < .001) and total nitrogen removal (80 ± 5% vs. 38 ± 23% reduction, p < .001) due to higher rates of microbially-mediated denitrification in the Treatment model. The two models performed comparably with regard to phosphorus reduction (84 ± 9% vs. 82 ± 12% reduction). A minimum 6 m filter width is recommended to ensure sufficient infiltration of runoff and nitrogen removal. Results of this study address uncertainty regarding nutrient removal performance of VFS in urban runoff applications and highlight a potential strategy for standardizing VFS performance across varied soil properties by including engineered media within the filter.
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Affiliation(s)
- Mohammad Shokri
- University of Central Florida, Civil, Environmental, And Construction Engineering Dept. 4000 Central Florida Blvd., Orlando, Fl, 32816, USA.
| | - Kelly M Kibler
- University of Central Florida, Civil, Environmental, And Construction Engineering Dept. and National Center for Integrated Coastal Research, 12800 Pegasus Drive, Orlando, Fl, 32816, USA.
| | - Christopher Hagglund
- University of Central Florida, Civil, Environmental, And Construction Engineering Dept. 4000 Central Florida Blvd., Orlando, Fl, 32816, USA.
| | - Andrew Corrado
- University of Central Florida, Civil, Environmental, And Construction Engineering Dept. 4000 Central Florida Blvd., Orlando, Fl, 32816, USA.
| | - Dingbao Wang
- University of Central Florida, Civil, Environmental, And Construction Engineering Dept. 4000 Central Florida Blvd., Orlando, Fl, 32816, USA.
| | - Melanie Beazley
- University of Central Florida, Department of Chemistry, Physical Sciences Building 205. 4111 Libra Drive, Orlando, Fl, 32816, USA.
| | - Martin Wanielista
- University of Central Florida, Civil, Environmental, And Construction Engineering Dept. 12800 Pegasus Drive, Orlando, Fl, 32816, USA.
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Javanian M, Bayani M, Shokri M, Sadeghi-Haddad-Zavareh M, Babazadeh A, Ghadimi R, Sepidarkish M, Bijani A, Yahyapour Y, Barary M, Hasanpour AH, Ebrahimpour S. Risk factors for mortality of 557 adult patients with COVID 19 in Babol, Northern Iran: a retrospective cohort study. BRATISL MED J 2021; 122:34-38. [PMID: 33393318 DOI: 10.4149/bll_2021_003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND This study was aimed to investigate the risk factors for mortality in patients with COVID-19. METHODS For this retrospective cohort study, we included 121 deceased and 436 discharged cases with COVID-19 in Babol, Northern Iran. The cases were between March 1 to April 1, 2020. RESULTS Multivariate Poisson regression analysis revealed that older age (aRR: 1.03, 95% CI: 1.01, 1.05, p < 0.001), hospital length of stay (aRR: 0.94, 95% CI: 0.90, 0.97, p = 0.003), ICU admission (aRR: 4.34, 95% CI: 2.95, 6.37, p < 0.001), cerebrovascular disease (aRR: 1.96, 95% CI: 1.20, 3.19, p = 0.007), ventilator-associated pneumonia (VAP) (aRR: 2.09, 95% CI: 1.22, 3.55, p = 0.006), septic shock (aRR: 2.98, 95% CI: 1.44, 6.19, p = 0.003), acute respiratory distress syndrome (ARDS) (aRR: 3.80, 95% CI: 2.28, 6.31, p < 0.001), acute kidney failure (AKF) (aRR: 1.45, 95% CI: 1.12, 3.76, p = 0.021), acute heart failure (AHF) (aRR: 1.63, 95% CI: 1.01, 2.62, p = 0.043) and lymphocyte count (aRR: 3.01, 95% CI: 1.99, 4.57, p < 0.001) were associated with mortality. CONCLUSION Findings showed that elderly with comorbidities such as cerebrovascular diseases had an increased risk of death. Some complications such as: pneumonia, septic shock, ARDS, AHF, and AKF played crucial roles as well death (Tab. 2, Ref. 25).
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Shokri M, Taghinavaz F. Conformal Bjorken flow in the general frame and its attractor: Similarities and discrepancies with the Müller-Israel-Stewart formalism. Int J Clin Exp Med 2020. [DOI: 10.1103/physrevd.102.036022] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Wen D, Valencia A, Lustosa E, Ordonez D, Shokri M, Gao Y, Rice N, Kibler K, Chang NB, Wanielista MP. Evaluation of green sorption media blanket filters for nitrogen removal in a stormwater retention basin at varying groundwater conditions in a karst environment. Sci Total Environ 2020; 719:134826. [PMID: 31879034 DOI: 10.1016/j.scitotenv.2019.134826] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 10/01/2019] [Accepted: 10/03/2019] [Indexed: 06/10/2023]
Abstract
Removing excess nutrient from stormwater runoffs is necessary to protect the water quality of receiving water bodies such as rivers, lakes, springs, and groundwater aquifers. Silver Springs Springshed, located in the vicinity of Ocala, Florida, has received widespread attention from the local government and residents due to its long-term nutrient impact, which has resulted in eutrophication. Blanket filters containing Bio-sorption Activated Media (BAM) were implemented with different depths of the vadose zone in a stormwater retention basin. The design combined the interaction with groundwater as an innovative Best Management Practice can potentially boost the performance of nutrient removal. Selected storm runoffs were collected at multiple points that cover the runoff timeframe to determine the pollutant load. Infiltrating water samples were collected at various depths within BAM using lysimeters to validate the treatment effectiveness. Significant pollutant load reduction of nutrients was confirmed with highest 99% and 91% removal of nitrate and nitrite (NOx) and total nitrogen (TN) at the deep blanket filter (with more groundwater intrusion impacts) due to more effective denitrification and longer contact time. Yet the highest pollutant load reduction of 93% and 84% removal of NOx and TN was also observed at the shallow blanket filter (with less groundwater intrusion impacts). On the other hand, better pollutant load reduction of ammonia in the BAM layer was found at the shallow blanket filter presumably due to more available oxygen for nitrification.
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Affiliation(s)
- Dan Wen
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL 32816, USA
| | - Andrea Valencia
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL 32816, USA
| | - Eranildo Lustosa
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL 32816, USA
| | - Diana Ordonez
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL 32816, USA
| | - Mohammad Shokri
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL 32816, USA
| | - Yuan Gao
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL 32816, USA
| | - Nyle Rice
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL 32816, USA
| | - Kelly Kibler
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL 32816, USA
| | - Ni-Bin Chang
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL 32816, USA.
| | - Martin P Wanielista
- Department of Civil, Environmental, and Construction Engineering, University of Central Florida, Orlando, FL 32816, USA
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Borjian Boroujeni Z, Hashemi SJ, Daie Ghazvini R, Khodavaisy S, Zareei M, Hosseinpour L, Ardi P, Shokri M. Recurrent eumycetoma caused by novel species Madurella pseudomycetomatis: A case report. Med Mycol Case Rep 2019; 26:13-15. [PMID: 31667052 PMCID: PMC6812017 DOI: 10.1016/j.mmcr.2019.09.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 09/20/2019] [Accepted: 09/20/2019] [Indexed: 11/29/2022] Open
Abstract
Mycetoma is a chronic-granulomatous disease characterized by the inflammation, swollen organ, draining sinuses containing blood, pus, and grains. We present a case of madura foot with novel etiologic agent Madurella pseudomycetomatis. Diagnosis was based on morphologic, physiologic, histipathologic and molecular methods. In vitro antifungal susceptibility tests revealed that MIC values for itraconazole, amphotericin B, and posaconazole were 0.0313 μg/ml, 0.0313 μg/ml, and 0.004 μg/ml, respectively. The patient was treated and recovered by itraconazole(400 mg/day) after prolonged course.
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Affiliation(s)
- Zeinab Borjian Boroujeni
- Department of Medical Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR, Iran
| | - Seyed Jamal Hashemi
- Department of Medical Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR, Iran
| | - Roshank Daie Ghazvini
- Department of Medical Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR, Iran
| | - Sadegh Khodavaisy
- Department of Medical Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR, Iran
| | - Mahdi Zareei
- Department of Health, Rescue and Treatment of IR Iran Police Force, Tehran, Iran
| | - Leila Hosseinpour
- Department of Medical Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR, Iran
| | - Pegah Ardi
- Department of Medical Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, IR, Iran
| | - Mohammad Shokri
- Department of Health, Rescue and Treatment of IR Iran Police Force, Tehran, Iran
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Shokri M, Vesper DJ, Herman EK, Rajic L, Hetrick KL, Padilla IY, Alshawabkeh AN. BULK CHEMISTRY OF KARST SEDIMENT DEPOSITS. Sinkholes Eng Environ Impacts Karst 2018; 2018:115-120. [PMID: 31435622 DOI: 10.5038/9780991000982.1043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Sediments are ubiquitous in karst systems and play a critical role in the fate and transport of contaminants. Sorbed contaminants may be stored on immobile sediments or rapidly dispersed on mobile sediments. Sediments may also influence remediation by either enhancing or interfering with the process. To better understand the potential effects of sediments on remediation, we conducted physical and chemical characterizations of 11 sediment samples from 7 cave and spring deposits from karst regions of Tennessee, Virginia, and West Virginia. The samples were analyzed for particle-size distribution using sieves and laser diffraction particle analysis. The sediment size fraction <2 mm (sand, silt, and clay) was analyzed for slurry pH and specific conductivity (SC) using electrodes and for bulk total carbon, organic carbon, nitrogen and sulfur on an ElementarTM Vario MAX Cube CNS. The same <2 mm fraction was subjected to a pseudo-total extraction using aqua regia with subsequent solution analysis by inductively coupled plasma-optical emission spectrometry (ICP-OES). Most of the samples were dominated by the <2 mm size fraction. Their slurry pHs ranged from 6.8 to 8.4 and their SCs ranged from 45 to 206 μS/cm with the exception of two high SC samples (726 and 8500 μS/cm). The fraction of organic carbon (Foc) in the sediments ranged from <0.1 to 2%. The sample from a saltpeter cave historically used for gunpowder production contained the highest concentrations of N and S (~3 g/kg) but lower total C than some of the spring samples. The pseudo-total extractions were analyzed for Al, Ca, Fe, Mg, and Mn. Of those elements, Mg was the most consistent across the locations (2.0-6.1 g/kg), and Ca was the most variable (1.4-52 g/kg). Given the importance of particle size and elemental concentrations in chemical reactions and remediation, more data of this type are needed to predict contaminant fate and transport and to plan successful remediation projects.
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Affiliation(s)
- Mohammad Shokri
- West Virginia University, Dept. of Geology and Geography, 98 Beechurst Ave., Morgantown, WV 26506, USA,
| | - Dorothy J Vesper
- West Virginia University, Dept. of Geology and Geography, 98 Beechurst Ave., Morgantown, WV 26506, USA,
| | - Ellen K Herman
- Bucknell University, Dept. of Geology and Environmental Geosciences, 1 Dent Drive, Lewisburg, PA, 17837, USA,
| | - Ljiljana Rajic
- Northeastern University, Dept. of Civil and Environmental Engineering, 360 Huntington Ave., Boston, MA, 02115, USA,
| | - Kimberly L Hetrick
- Northeastern University, Dept. of Civil and Environmental Engineering, 360 Huntington Ave., Boston, MA, 02115, USA,
| | - Ingrid Y Padilla
- University of Puerto Rico, Mayagüez, Dept, of Civil Engineering and Surveying, Calle Yagrumo, Mayagüez, PR, 00681, USA,
| | - Akram N Alshawabkeh
- Northeastern University, Dept. of Civil and Environmental Engineering, 360 Huntington Ave., Boston, MA, 02115, USA,
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Hetrick KL, Rajic L, Alshawabkeh AN, Shokri M, Vesper DJ. LABORATORY TESTING OF THE POTENTIAL FOR THE INFLUENCE OF SUSPENDED SEDIMENTS ON THE ELECTROCHEMICAL REMEDIATION OF KARST GROUNDWATER. Sinkholes Eng Environ Impacts Karst 2018; 2018:147-152. [PMID: 31435623 PMCID: PMC6703559 DOI: 10.5038/9780991000982.1017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Due to the complicated nature of karst aquifers, many groundwater treatment technologies are difficult to implement successfully. A particular challenge arises because sediments are ubiquitous and mobile in karst systems and may either facilitate contaminant transport or act as long-term substrates for storage via sorption. However, electrochemical remediation is a promising technology to be optimized for karst aquifers due to easy manipulation and control of groundwater chemistry as well as low cost, ability for in situ application, and performance under alternative power sources. This study investigates the effects of suspended karst sediments on the electrochemical remediation of groundwater via electro-Fenton (EF) mechanism. The EF mechanism relies on direct electrolysis (i.e., water electrolysis and ferrous iron release) and indirect, electrochemically-induced processes (i.e., Pd catalyzed H2O2 production). These processes can be optimized for H2O2 generation and support of its activation to hydroxyl radicals - a powerful oxidant capable of degrading and transforming a wide range of contaminants (e.g., chlorinated solvents). In this study, we tested sediments varying in concentrations of Fe, Mn and buffering capacities. When the sediments were introduced into the EF experiments, there were adverse effects on the H2O2 content: at steady state (120 min), Pd catalyzed formation of H2O2 decreased by 60%, 57%, and 75% in the presence of suspended sediment collected from three separate karst locations. Presented results imply that sediments' presence influences EF mechanism in electrochemical systems, but given the flexibility of the technology, it can be optimized in terms of electrode materials, current intensities and current regimes to address these challenges.
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Affiliation(s)
- Kimberly L Hetrick
- Northeastern University, Dept. of Civil and Environmental Engineering, 360 Huntington Ave., Boston, MA, 02115, USA,
| | - Ljiljana Rajic
- Northeastern University, Dept. of Civil and Environmental Engineering, 360 Huntington Ave., Boston, MA, 02115, USA,
| | - Akram N Alshawabkeh
- Northeastern University, Dept. of Civil and Environmental Engineering, 360 Huntington Ave., Boston, M.A, 02115, USA,
| | - Mohammad Shokri
- University of Central Florida, Civil, Environmental, and Construction Engineering Dept., 12800 Pegasus Drive, Orlando, FL, 32816, USA,
| | - Dorothy J Vesper
- West Virginia University, Dept. of Geology and Geography, 98 Beechurst Ave., Morgantown, WV 26506, USA,
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Naderi M, Hoseinabadi M, Najafi M, Motahari S, Shokri M. Investigation of the mechanical, thermal, and anticorrosion properties of epoxy nanocomposite coatings: Effect of synthetic hardener and nanoporous graphene. J Appl Polym Sci 2018. [DOI: 10.1002/app.46201] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- Mehdi Naderi
- Department of Polymer Engineering, School of Chemical Engineering, College of Engineering; University of Tehran, P.O. Box 11155-4563; Tehran Iran
| | - Morteza Hoseinabadi
- Department of Polymer Engineering, School of Chemical Engineering, College of Engineering; University of Tehran, P.O. Box 11155-4563; Tehran Iran
| | - Mohammad Najafi
- Department of Polymer Engineering, School of Chemical Engineering, College of Engineering; University of Tehran, P.O. Box 11155-4563; Tehran Iran
| | - Siamak Motahari
- Department of Polymer Engineering, School of Chemical Engineering, College of Engineering; University of Tehran, P.O. Box 11155-4563; Tehran Iran
| | - Mohammad Shokri
- Research and Development Center, Fanavaran Resin Chimie Parseh Co. (PUTECH Industrial Group), P.O. Box 14579-14511; Tehran Iran
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Akbari Shorgoli A, Shokri M. Photocatalytic degradation of imidacloprid pesticide in aqueous solution by TiO2nanoparticles immobilized on the glass plate. CHEM ENG COMMUN 2017. [DOI: 10.1080/00986445.2017.1337005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Affiliation(s)
| | - Mohammad Shokri
- Department of Chemistry, Tabriz Branch, Islamic Azad University, Tabriz, Iran
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Hoseinabadi M, Naderi M, Najafi M, Motahari S, Shokri M. A study of rigid polyurethane foams: The effect of synthesized polyols and nanoporous graphene. J Appl Polym Sci 2017. [DOI: 10.1002/app.45001] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Morteza Hoseinabadi
- Department of Polymer Engineering; School of Chemical Engineering, College of Engineering, University of Tehran; P.O. Box 11155-4563 Tehran Iran
| | - Mehdi Naderi
- Department of Polymer Engineering; School of Chemical Engineering, College of Engineering, University of Tehran; P.O. Box 11155-4563 Tehran Iran
| | - Mohammad Najafi
- Department of Polymer Engineering; School of Chemical Engineering, College of Engineering, University of Tehran; P.O. Box 11155-4563 Tehran Iran
| | - Siamak Motahari
- Department of Polymer Engineering; School of Chemical Engineering, College of Engineering, University of Tehran; P.O. Box 11155-4563 Tehran Iran
| | - Mohammad Shokri
- Fanavaran Resin Chimie Parseh Co. (PUTECH Industrial Group); Research & Development Center; P.O. Box 14579-14511 Tehran Iran
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Shokri M, Isapour G, Hosseini MG, Zarbpoor Q. Enhanced Photocatalytic Activity of Ag Doped ZnO Nanorods for Degradation of an Azo Dye. Water Environ Res 2016; 88:2001-2007. [PMID: 28661319 DOI: 10.2175/106143016x14733681695168] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In this study, Ag-ZnO nanophotocatalyst has been synthesized through microemulsion technique and the effect of silver modification on ZnO nanorods has been evaluated. The photocatalytic activity of nanocatalyst was examined by degradation of Acid Yellow 23 (AY23) as a model of mono azo dye under UV illumination. Ag-ZnO catalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDXS) and diffuse reflectance spectroscopy (DRS) analysis. The degradation of AY23 was studied under different operational parameters. Results show that the photocatalytic reaction followed the pseudo-first-order kinetic. The highest photocatalytic degradation of 20 mg/L AY23 dye solution under UV irradiation (light intensity = 50 W/m2 , [Ag-ZnO]0 = 400 mg/L with 2 wt% Ag doped ZnO, calcined at 450 °C) was about 93.3% during 30 minutes of reaction that shows an enhancement in comparison to pure ZnO which was 65.48%.
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Affiliation(s)
- Mohammad Shokri
- Department of Chemistry, Tabriz Branch, Islamic Azad University, Tabriz, Iran
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Rahimi P, Solati R, Shokri M, Vahabpour R, Mahmoudizad F, Aghasadeghi MR, Motevalli F, Yazdani S, Shayestehpour M, Amiran MR. Evaluation of full length E1 and E2 glycoproteins of HCV expressed in P. pastoris as a protein-based vaccine candidate. vacres 2015. [DOI: 10.18869/acadpub.vacres.2.4.74] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Shokri M, Jodat A, Modirshahla N, Behnajady MA. Photocatalytic degradation of chloramphenicol in an aqueous suspension of silver-doped TiO2 nanoparticles. Environ Technol 2013; 34:1161-1166. [PMID: 24191448 DOI: 10.1080/09593330.2012.743589] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
In this work, silver-doped TiO2 (Ag/TiO2) nanoparticles were synthesized using a photodeposition technique. The prepared Ag/TiO2 nanoparticles were characterized using TEM, SEM, XRD, and EDX techniques. The characterization of Ag/TiO2 nanoparticles using SEM and EDX techniques revealed the dispersion of Ag metal on the surface of TiO2. The photocatalytic activity of Ag/TiO2 and bare TiO2 in the presence of ultraviolet irradiation was investigated in the removal of chloramphenicol (CAP) as an antibiotic. CAP is a broad-spectrum antibiotic exhibiting activity against both Gram-positive and Gram-negative bacteria, as well as other groups of microorganisms. However, it is, in certain susceptible individuals, associated with serious toxic effects in humans including bone marrow depression, particularly severe in the form of fatal aplastic anaemia. The effects of the operational factors, such as doping content of Ag, photocatalyst dosage and calcination temperature were evaluated in the catalytic activity of Ag/TiO2. The results showed that the photocatalytic efficiency of TiO2 nanoparticles for the degradation of CAP, can be significantly improved by deposition an optimum amount of Ag nanoparticles (0.96 wt%) in the calcination temperature 300 degrees C. It was found that 900 mg/L of Ag/TiO2 is the optimum dosage in the removal of CAP with 20 mg/L initial concentration. The highest removal efficiency of CAP (-100%) at the optimum conditions was observed in 20 min. A mineralization study under optimum conditions showed about 88% reduction in total organic carbon after 120 min of irradiation time.
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Affiliation(s)
- Mohammad Shokri
- Department of Applied Chemistry, Faculty of Science, Tabriz Branch, Islamic Azad University, Tabriz, Iran.
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Behnajady MA, Mansoriieh N, Modirshahla N, Shokri M. Influence of operational parameters and kinetics analysis on the photocatalytic reduction of Cr(VI) by immobilized ZnO. Environ Technol 2012; 33:265-271. [PMID: 22519111 DOI: 10.1080/09593330.2011.569957] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In the present work the performance of immobilized ZnO on a glass plate with the heat attachment method has been described for photoreduction of Cr(VI) to the less harmful Cr(III) at different operational parameters. The photoreduction of Cr(VI) on the surface of the immobilized ZnO catalyst was studied as a function of the pH of solution, initial Cr(VI) concentration and ultraviolet (UV) light intensity. Results indicated that the reduction rate decreases with increasing initial concentration of Cr(VI) and initial pH of solution, whereas it increases with increasing UV light intensity. The photoreduction rate of Cr(VI) on the surface of the immobilized ZnO in the presence of O2 as mobile gas is more than Ar and N2. The reduction process of Cr(VI) by immobilized ZnO also could be done under visible light irradiation. Pseudo first-order kinetics were observed for the photoreduction of Cr(VI) at different operational conditions. With non-linear regression analysis a mathematical kinetics model was developed for the pseudo first-order constant (k(ap)) as a function of operational parameters.
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Affiliation(s)
- Mohammad A Behnajady
- Department of Chemistry, Faculty of Science, Tabriz Branch, Islamic Azad University, Tabriz, I. R. Iran.
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Ghoulipour V, Shokri M, Waqif-Husain S. Determination of ampicillin and amoxicillin by high-performance thin-layer chromatography. ACTA CHROMATOGR 2011. [DOI: 10.1556/achrom.23.2011.3.9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Behnajady MA, Eskandarloo H, Modirshahla N, Shokri M. Sol-Gel Low-temperature Synthesis of Stable Anatase-type TiO2 Nanoparticles Under Different Conditions and its Photocatalytic Activity. Photochem Photobiol 2011; 87:1002-8. [DOI: 10.1111/j.1751-1097.2011.00954.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Behnajady MA, Eskandarloo H, Modirshahla N, Shokri M. Sol-gel low-temperature synthesis of stable anatase-type TiO2 nanoparticles under different conditions and its photocatalytic activity. Photochem Photobiol 2011. [PMID: 21668867 DOI: 10.1111/j.1751‐1097.2011.00954.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this work, TiO(2) nanoparticles in anatase phase was prepared by sol-gel low temperature method from titanium tetra-isopropoxide (TTIP) as titanium precursor in the presence of acetic acid (AcOH). The effects of synthesis parameters such as AcOH and water ratios, sol formation time, synthesis and calcination temperature on the photocatalytic activity of TiO(2) nanoparticles were evaluated. The resulting nanoparticles were characterized by X-ray diffraction, UV-Vis reflectance spectroscopy, transmission electron microscopy and Brunauer-Emmett-Teller techniques. Photocatalytic activity of anatase TiO(2) nanoparticles determined in the removal of C. I. Acid Red 27 (AR27) under UV light irradiation. Results indicate that with increasing AcOH/TTIP molar ratio from 1 to 10, sol formation time from 1 to 3 h and synthesis temperature from 0 to 25°C, increases crystallite size of synthesized nanoparticles. It was found that optimal conditions for low temperature preparation of anatase-type TiO(2) nanoparticles with high photocatalytic activity were as follows: TTIP:AcOH:water molar ratio 1:1:200, sol formation time 1 h, synthesis temperature 0°C and calcination temperature 450°C.
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Affiliation(s)
- Mohammad A Behnajady
- Department of Chemistry, Faculty of Science, Tabriz Branch, Islamic Azad University, Tabriz, Iran.
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Behnajady MA, Amirmohammadi-Sorkhabi S, Modirshahla N, Shokri M. Investigation of the efficiency of a tubular continuous-flow photoreactor with supported titanium dioxide nanoparticles in the removal of 4-nitrophenol: operational parameters, kinetics analysis and mineralization studies. Water Sci Technol 2011; 64:56-62. [PMID: 22053458 DOI: 10.2166/wst.2011.666] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In this study, to investigate the application of heterogeneous photocatalysis in the removal of organic contaminants from aqueous media a novel tubular continuous-flow photoreactor with supported TiO2-P25 on glass plates was designed and constructed. The photoreactor comprises six quartz tubes and a UV lamp which was placed in the center of the quartz tubes. 4-nitrophenol (4-NP) as a most refractory pollutant was chosen as a probe pollutant to examine the photoreactor efficiency for environmental cleaning applications. Results of experiments show that the removal efficiency of 4-NP in this photoreactor is a function of photoreactor length, gas and liquid flow rates and 4-NP initial concentration. Kinetics analysis indicates that degradation of 4-NP in continuous-mode can be modeled with the Langmuir-Hinshelwood (L-H) model (k(L-H) = 1.5 mg L(-1) min(-1), K(ads) = 0.11 mg(-1) L). A design equation was obtained with a combination of L-H modified equation and tubular reactor design equation. This equation can be used for estimation of 4-NP concentration in different photoreactor lengths under various operational parameters. Mineralization study was followed through total organic carbon (TOC) analysis and measurement of nitrite and nitrate as final degradation products.
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Affiliation(s)
- Mohammad A Behnajady
- Department of Chemistry, Faculty of Science, Tabriz Branch, Islamic Azad University, Tabriz, Iran.
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Behnajady MA, Modirshahla N, Shokri M, Vahid B. Design equation with mathematical kinetic modeling for photooxidative degradation of C.I. Acid Orange 7 in an annular continuous-flow photoreactor. J Hazard Mater 2009; 165:168-173. [PMID: 18990487 DOI: 10.1016/j.jhazmat.2008.09.095] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2008] [Revised: 09/09/2008] [Accepted: 09/23/2008] [Indexed: 05/27/2023]
Abstract
The decolorization of C.I. Acid Orange 7 (AO7), an anionic monoazo dye of acid class was investigated using UV/H(2)O(2) process in an annular continuous-flow photoreactor (ACFP) as a function of oxidant, dye concentrations, reactor length and volumetric flow rate. The removal efficiency of AO7 was a function of operational parameters and increased with increasing initial concentration of H(2)O(2) but it was low at high flow rate and initial concentration of AO7. Results indicated that the decolorization rate was pseudo-first order kinetic with respect to the dye concentration. A rate equation for decolorization of AO7 was obtained by kinetic modeling. Design equation for ACFP reactor was obtained with combination of kinetic model and rearranged tubular reactor design equation. Design equation was used for predicting concentration of AO7 and also electrical energy per order (E(EO)) at different conditions. The calculated results obtained from design equation and kinetic model were in good agreement with experimental data.
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Affiliation(s)
- Mohammad A Behnajady
- Department of Applied Chemistry, Research Laboratory, Islamic Azad University, Tabriz Branch, Tabriz, Iran.
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Behnajady MA, Modirshahla N, Shokri M, Zeininezhad A, Zamani HA. Enhancement photocatalytic activity of ZnO nanoparticles by silver doping with optimization of photodeposition method parameters. J Environ Sci Health A Tox Hazard Subst Environ Eng 2009; 44:666-672. [PMID: 19412848 DOI: 10.1080/10934520902847752] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The photocatalytic activity of silver-doped ZnO was tested by photocatalytic degradation of C.I. Acid Red 88 (AR88) as a model contaminant from monoazo textile dyes. Silver-doped ZnO was prepared by photodeposition (PD) method. Results show that silver-doped ZnO is more efficient than undoped ZnO at photocatalytic degradation of AR88. The PD method parameters such as irradiation time, calcination temperature and silver content of doping were effective on the photoactivity of silver-doped ZnO. Silver content had an optimum value of 0.5% for achieving high photocatalytic activity. In the real wastewater from a textile-dyeing factory color removal with pure and silver-doped ZnO after 18 min of irradiation were 45 and 90%, respectively.
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Behnajady MA, Modirshahla N, Shokri M, Vahid B. Effect of operational parameters on degradation of Malachite Green by ultrasonic irradiation. Ultrason Sonochem 2008; 15:1009-14. [PMID: 18442946 DOI: 10.1016/j.ultsonch.2008.03.004] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2007] [Revised: 03/13/2008] [Accepted: 03/17/2008] [Indexed: 05/03/2023]
Abstract
The aim of the present study was to apply ultrasonic technique to remove Malachite Oxalate Green (MG) from aqueous solution. An ultrasonic bath with frequency of 35 kHz was used to investigate the effect of different operational parameters such as MG concentration, power density, temperature, mechanical agitation and addition of EtOH, 2-PrOH and iso-BuOH. Decolorization of MG follows a first order kinetics and hydroxyl radicals have an important role in degradation of MG. The apparent reaction rate constant (k(ap)) was influenced by variation of operational parameters. The activation energy was 30.95 kJ/mol in temperature range of 21-34 degrees C, suggesting a diffusion-controlled reaction. Alcohols act as hydroxyl radicals scavengers having undesirable contribution. UV-vis spectral change of MG showed hypsochromic shift occurred with increasing sonication time, proposing N-demethylation process of MG.
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Affiliation(s)
- Mohammad A Behnajady
- Department of Applied Chemistry, Islamic Azad University, Tabriz Branch, P.O. Box 1655, Tabriz, IR, Iran.
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Behnajady MA, Modirshahla N, Shokri M, Elham H, Zeininezhad A. The effect of particle size and crystal structure of titanium dioxide nanoparticles on the photocatalytic properties. J Environ Sci Health A Tox Hazard Subst Environ Eng 2008; 43:460-467. [PMID: 18324532 DOI: 10.1080/10934520701796267] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Titanium dioxide nanoparticles with different average diameter of particles (8, 18 and 27 nm) and different crystal structure (anatase and rutile) were used for degradation of C.I. Acid Red 88 (AR88) as a model compound. The degree of degradation of AR88 by TiO(2) nanoparticles under irradiation of UV-light (254nm) with TiO(2)-UV100 (8 nm diameter and 100% anatase) is lower than TiO(2)-Merck (27 nm diameter and 95% anatase). TiO(2)-P25 with structure of anatase and rutile (80:20) combination shows higher photoactivity than other samples such as TiO(2)-UV100 and TiO(2)-Merck. Kinetics of removal of AR88 with all of nanosized-TiO(2) particles is pseudo-first-order. The apparent reaction rate constant (k(ap)) for removal of AR88 in the presence of different nanosized-TiO2 particles decreases with increasing of AR88 initial concentration. For TiO(2)-P25 and TiO(2)-UV100 a linear relation and for TiO(2)-Merck a nonlinear relation between k(ap) and light intensity were obtained.
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Behnajady MA, Modirshahla N, Shokri M. Photodestruction of Acid Orange 7 (AO7) in aqueous solutions by UV/H2O2: influence of operational parameters. Chemosphere 2004; 55:129-134. [PMID: 14720555 DOI: 10.1016/j.chemosphere.2003.10.054] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The photodestruction of Acid Orange 7 (AO7), an anionic acidic dye, was studied in the UV/H2O2 process. H2O2 and UV light have a negligible effect when they were used on their own. Removal efficiency of AO7 was sensitive to the operational parameters such as initial H2O2 concentration, initial AO7 concentration, pH and different light sources. The photodestruction of AO7 was inhibited by addition of EtOH as an electron scavenger. The semi-logarithmic graphs of the concentration of AO7 versus time (t<30 min) were linear, suggesting pseudo-first order reactions (k(optimum)=0.105 min(-1)). A simple kinetic model is proposed which is in agreement with experimental results.
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Affiliation(s)
- M A Behnajady
- Department of Applied Chemistry, Islamic Azad University, Tabriz Branch, P.O. Box 1655, Tabriz, IR, Iran.
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Affiliation(s)
- A J Hickey
- Department of Pharmaceutics, College of Pharmacy, University of Illinois, Chicago 60680
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