Review Paper
Nikta Shahcheraghi; Sahand Shafeei; Zahra Mostafaei; Soroush Namjoufar
Abstract
Providing safe and clean water for a rapidly growing population is a critical global challenge. Nanotechnology-based membranes, or nanomembranes, represent a promising pathway toward sustainable wastewater treatment. Their ultra-thin, highporosity structure can offer superior contaminant removal, enhanced ...
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Providing safe and clean water for a rapidly growing population is a critical global challenge. Nanotechnology-based membranes, or nanomembranes, represent a promising pathway toward sustainable wastewater treatment. Their ultra-thin, highporosity structure can offer superior contaminant removal, enhanced flux, and lower energy consumption compared to conventional membranes. This review addresses both the fundamental principles and the latest advancements of nanomembranes, with an emphasis on the practical hurdles that currently impede widespread industrial adoption. Issues such as fouling, short operational lifespans, and cost barriers are discussed. In addition, the text highlights emerging materials and fabrication strategies, including two-dimensional (2D) nanosheets such asgraphene oxide and MXenes, as well as composite membranes integrated with metal-organic frameworks or covalent organic frameworks. Real-world applications are summarized, along with a discussion of how specialized membrane designs can reduce fouling in large-scale treatment plants. The review concludes by proposing future research directions that could make nanomembrane technologies both economically viable and environmentally safe, and by illustrating how these novel systems can be scaled up to help achieve global clean-water sustainability goals.
Research Paper
Hedieh Ahmadpari; Vitaly Khaustov; Ata Amini
Abstract
This study explores agricultural drought variability by applying both classical and rank-based statistical methods within two distinct probabilistic frameworks, aiming to assess how distribution choice affects the interpretation of drought patterns. Monthly meteorological data from 1998 to 2022 were ...
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This study explores agricultural drought variability by applying both classical and rank-based statistical methods within two distinct probabilistic frameworks, aiming to assess how distribution choice affects the interpretation of drought patterns. Monthly meteorological data from 1998 to 2022 were processed into four drought indices: SPI, aSPI, RDI, and eRDI. Effective precipitation was calculated using the USDA method and CROPWAT, and potential evapotranspiration (ET0) was determined with the FAO Penman-Monteith approach. Each index was standardized with both gamma and log-normal distributions in DrinC to evaluate the influence of distribution choice on trend detection. Trend analysis was conducted using linear regression with Pearson correlation for parametric tests and the Mann–Kendall test with Sen’s slope for non-parametric tests. Results from both methods and distributions were consistent: median Sen slopes were within ±0.03 index units per year, and Mann–Kendall Z scores ranged from −0.82 to 0.63, indicating no significant monotonic change. Regression slopes supported this, remaining below 0.03 with p-values above 0.25. The close agreement between parametric and non-parametric results, and between gamma and log-normal distributions, shows that model selection does not bias drought trend analysis. This multi-index, dual-distribution framework provides a robust and transferable methodology for drought monitoring, particularly in data-scarce and semi-arid regions worldwide.
Research Paper
Neha Kulshreshtha; Vishal Kumar Sandhwar; Alok Tiwari; Shivendu Saxena; Ashish Mishra
Abstract
Ciprofloxacin (CIP), as a commonly used fluoroquinolone antibiotic, is frequently detected in pharmaceutical effluents and aquatic environments and poses significant microbiological hazards due to low biodegradability and high stability. In this study, heterogeneous catalytic oxidation of ciprofloxacin ...
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Ciprofloxacin (CIP), as a commonly used fluoroquinolone antibiotic, is frequently detected in pharmaceutical effluents and aquatic environments and poses significant microbiological hazards due to low biodegradability and high stability. In this study, heterogeneous catalytic oxidation of ciprofloxacin was explored using a bimetallic CuFe/Al₂O₃ catalyst synthesized by wet impregnation method. FTIR, XRD, SEM, and BET analyses characterized the catalyst, showing Cu and Fe oxides uniformly distributed on the Al₂O₃ support and a mesoporous structure with a specific surface area of 91.9 m² g⁻¹. Subsequently, batch oxidization experiments determined the influence of operating parameters (catalyst dosage, initial pH and reaction time) on ciprofloxacin removal efficiency. Box–Behnken Design (BBD)of Response Surface Methodology (RSM) verified process optimum and variable interaction analysis. Maximum CIP degradation of 80.66 % was observed in aqueous solution at optimal operating conditions. Kinetic studies showed pseudo-first-order kinetics (k = 0.0191 min⁻¹ (R² = 0.9911); t₁/₂ = 36.3 min) confirmed rapid oxidation. CuFe/Al₂O₃ showed superior performance due to the redox cycle of Cu²⁺/Cu⁺ and Fe³⁺/Fe²⁺ species, advantageous generation of hydroxyl radicals from heterogeneous Fenton-like reactions. Therefore, the results support that CuFe/Al₂O₃ catalyst is a worthwhile and stable catalyst for antibiotic breakdown via advanced oxidation for sustainable pharmaceutical wastewater treatment.
Research Paper
Sara Heshmatian; Hooman Bakhshi; Shohreh Azizi; Itani Given Madiba
Abstract
This study presents a sustainable approach for converting waste sheep wool into high-performance activated carbon for Cr(VI) removal from aqueous solutions. Chemical (NaOH) and steam activation routes were evaluated, and steam activation at 900 °C for 3 h in a rotary furnace produced the optimal ...
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This study presents a sustainable approach for converting waste sheep wool into high-performance activated carbon for Cr(VI) removal from aqueous solutions. Chemical (NaOH) and steam activation routes were evaluated, and steam activation at 900 °C for 3 h in a rotary furnace produced the optimal material. The resulting carbon exhibited a high specific surface area (1807 m²/g), a pore volume of 1.002 cm³/g, and a well-developed micro-mesoporous structure. The optimized adsorbent achieved 99% removal of Cr(VI) from a 400 mg/L solution within 45 min. Physicochemical characterization (BET, SEM, XRD, Raman) and adsorption analysis (ICP-OES) confirmed the material’s suitability for adsorption processes. Equilibrium behavior was best described by the Freundlich isotherm (R² = 0.976), while the Langmuir model yielded a monolayer capacity of 147 mg/g. Kinetic data closely followed the pseudo-second-order model (R² = 0.999), suggesting adsorption dominated by electrostatic interactions and surface complexation under acidic conditions. These findings demonstrate that wool waste can be effectively valorized as a low-cost, scalable, and efficient adsorbent for Cr(VI) remediation.
Research Paper
Moein Tosan; Afshin Shayeghi; Javad Teymouri; Aydin Bakhtar
Abstract
Reliable multi-step-ahead forecasting of reference evapotranspiration (ETo) is critical for proactive water resource management, yet understanding the temporal memory of hydrological systems remains a challenge for black-box deep learning models. This study presents a novel, interpretable forecasting ...
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Reliable multi-step-ahead forecasting of reference evapotranspiration (ETo) is critical for proactive water resource management, yet understanding the temporal memory of hydrological systems remains a challenge for black-box deep learning models. This study presents a novel, interpretable forecasting framework integrating temporal SHapley additive explanations (SHAP) with advanced recurrent neural networks to predict daily ETo up to 7 days in advance across three contrasting climatic zones in Iran; Birjand (arid), Mashhad (semi-arid), and Gorgan (humid). By benchmarking long short-term memory (LSTM), bidirectional LSTM (BiLSTM), and CNN-LSTM architectures, it is demonstrated that model complexity does not always guarantee superiority; the standard LSTM proved remarkably robust, achieving high short-term accuracy (R² > 0.93 for 1-day forecast) in arid regions. However, a distinct humid-climate penalty was observed, with forecast accuracy degrading more rapidly in Gorgan due to stochastic cloud dynamics. The application of temporal SHAP revealed climate-specific memory effects: in arid zones, wind speed exhibited a persistent influence extending back 5 days, acting as a long-term driver of evaporative demand, whereas humid regions were governed by short-term radiative pulses. Furthermore, analysis of extreme events and drought propagation showed that while the model successfully captures heatwave-driven peaks, its reliability decreases under severe evaporative stress (standardized ETo anomaly > 2). Cross-spatial generalization tests confirmed that models trained on arid data transfer effectively to humid regions (R² = 0.95), but the reverse transfer fails to capture extreme advective forcing. This study provides a transferable, physically interpretable blueprint for developing early warning systems in data-scarce regions.
Research Paper
Maryam Hafezparast Mavaddat; Rasool Ghobadian; Sadaf Gord
Abstract
Floods rank among the most destructive natural disasters worldwide, with their frequency and intensity amplified by climate change. This study presents an integrated approach combining hydraulic modeling and multi-sensor satellite data to improve floodplain mapping accuracy during the April 3, 2019 flood ...
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Floods rank among the most destructive natural disasters worldwide, with their frequency and intensity amplified by climate change. This study presents an integrated approach combining hydraulic modeling and multi-sensor satellite data to improve floodplain mapping accuracy during the April 3, 2019 flood event in Kermanshah, western Iran. The research focuses on the confluence of the Gharasoo, Merek, and Razavar rivers, where combined flows created significant flood risks for Kermanshah city. The study makes several important methodological contributions to flood modeling. First, it demonstrates the value of simultaneous analysis of both steady and unsteady state conditions, providing a more comprehensive understanding of flood dynamics compared to conventional single-state approaches. Second, the integration of optical (Sentinel-2, Landsat) and radar (Sentinel-1) remote sensing data effectively overcomes the limitations of individual sensors, particularly in addressing cloud cover issues. Third, the implementation of Google Earth Engine enables near-real-time flood monitoring capabilities, significantly enhancing operational response potential. Finally, the development of robust validation metrics specifically adapted for flood model assessment represents an important step forward in model verification methodologies. HEC-Geo RAS simulations predicted extreme conditions with water levels rising up to 6 meters and flow velocities reaching 3m/s. Validation results showed strong agreement between unsteady state modeling and satellite observations (F1=0.73, F2=0.72), while steady-state conditions exhibited lower correlation (F1=0.41, F2=0.28). The model effectively tracked flood progression from inception to peak, while satellite imagery provided rapid regional coverage despite occasional cloud obstructions.
Research Paper
Neda Jafari; Yagob Dinpashoh; Ahmad Fakheri-Fard
Abstract
Water quality in rivers is a critical concern in hydrology. This study examines the Gadar-Chai River, situated within Iran's Urmia Lake basin, utilizing data from four selected hydrometric stations: Oshnavieh, Polebahramlu, Bighaleh, and Naghadeh. An improved Water Quality Index (ImpWQI) was calculated ...
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Water quality in rivers is a critical concern in hydrology. This study examines the Gadar-Chai River, situated within Iran's Urmia Lake basin, utilizing data from four selected hydrometric stations: Oshnavieh, Polebahramlu, Bighaleh, and Naghadeh. An improved Water Quality Index (ImpWQI) was calculated for each station using data from 2003 to 2021. Trends in ImpWQI values and the used water quality parameters, including the annual time series of TDS, EC, pH, HCO₃⁻, Cl⁻, SO₄²⁻, Ca²⁺, Mg²⁺, Na⁺, K⁺, and TH, were analyzed in the period 2003–2021. Three significance levels, at 1%, 5%, and 10%, were used. The Mann-Kendall (MK), Mod-ified Mann-Kendall (MMK), and innovative trend analysis (ITA) methods, as well as Sen's slope estimator, were used for trend detection and calculating the slope of trend lines. The results showed both upward and downward trends in the time se-ries. MK, MMK, and ITA showed similar results in detecting the trend direction, but differed in estimating trend magnitude. MMK tended to show stronger trends than MK .However, unlike the MK and MMK methods, which only identify monotonic trends, the ITA method is capable of detecting sub-trends. Among all the water quality variables of the Gadar-Chai Basin, the pH parameter had the highest num-ber of positive trends. Trends in the Cl- parameter were negative in almost all the stations. Trends in the ImpWQI index were negative in the three stations, namely Oshnavieh, Polebahramlu, and Naghadeh; however, station Bighale witnessed an upward trend in ImpWQI. A negative trend line slope was observed for the EC pa-rameter in the station Polebahramlou, whereas a positive slope was obtained for the same parameter in the station Bighaleh.
Research Paper
Zahra Yaghoubzadeh; Hassan Nasrollahzadeh Saravi; Sharareh Firouzkandian
Abstract
The Khersan River, the largest tributary of the Karun River, is regulated by the Khersan-3 Dam, constructed for flood control, irrigation management, and hydropower generation. Despite its strategic importance, no comprehensive study has previously assessed microbial water quality in this reservoir, ...
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The Khersan River, the largest tributary of the Karun River, is regulated by the Khersan-3 Dam, constructed for flood control, irrigation management, and hydropower generation. Despite its strategic importance, no comprehensive study has previously assessed microbial water quality in this reservoir, particularly under the pressure of intensive agricultural activities in the watershed. This study investigated heterotrophic bacteria, total and fecal coliforms, and protozoan (Giardia and Cryptosporidium) contamination in the Khersan-3 sub-basin. Monthly sampling was carried out from November 2023 to October 2024 at five stations using sterile glass bottles (100 ml) from the surface layer (20 cm depth). For protozoan detection, 10 liter samples were collected at Station 5. Results showed seasonal and spatial variations in microbial indicators. The highest mean concentration of heterotrophic bacteria was observed in autumn 2023 (6.237 Log CFU/100 ml), while the lowest occurred in summer 2024 (4.507 Log CFU/100 ml) (p<0.05). Total coliforms reached their maximum in winter 2023 (3.822 Log CFU/100 ml) and decreased to a minimum of 2.509 Log CFU/100 ml in summer 2024 (p<0.05). However, seasonal variations in the mean density of fecal coliforms were not statistically significant (p>0.05). Across stations, the densities of heterotrophs, total coliforms, and fecal coliforms did not differ significantly (p>0.05). Cryptosporidium was undetected in all samples, whereas no significant difference was found in Giardia occurrence among seasons, despite detection in approximately 40% of spring samples (p>0.05). This study provides the first evidence of substantial temporal and spatial fluctuations in indicator bacteria across the Khersan-3 Dam watershed, highlighting the influence of hydrological and anthropogenic drivers. The findings emphasize the need for targeted management actions, including continuous microbial surveillance, stricter control of agricultural runoff, and improved water treatment practices to safeguard public health and aquaculture sustainability.
Research Paper
Ali Nasirian; Raziyeh Shamshirgaran; Moein Tosan
Abstract
Despite concerted efforts to stabilize groundwater levels in arid regions through engineering interventions, aquifer depletion remains a critical challenge, often exacerbated by a disconnect between rigid top-down policies and local socio-economic realities. This study presents a forensic hydro-institutional ...
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Despite concerted efforts to stabilize groundwater levels in arid regions through engineering interventions, aquifer depletion remains a critical challenge, often exacerbated by a disconnect between rigid top-down policies and local socio-economic realities. This study presents a forensic hydro-institutional analysis of the restoration and balancing plan in the hyper-arid Boshruyeh Plain, Iran, to evaluate the efficacy of technical controls versus economic instruments. By integrating a 27-year hydro-physical time series (1995–2023) with a tripartite stakeholder analysis (farmers, executive experts, and academic elites), the research reveals a complex paradox. Hydrological results indicate that while the implementation of smart metering post-2014 successfully induced a structural break in abstraction trends and enforced regulatory compliance, it failed to arrest the chronic annual deficit of ~62 MCM. Socio-institutional analysis exposes a significant perception gap; while academic elites emphasize participatory governance, executive experts identify technical and cultural barriers as primary causes of policy failure. However, a strategic consensus was found regarding the potential of water markets. Contrasting with common assumptions of resistance, 89% of farmers expressed willingness to participate in a regulated market, driven primarily by the need for operational flexibility and drought risk management rather than profit maximization. The study concludes that sustainable aquifer restoration requires a paradigm shift from a purely police-patrol model to a cap-and-trade system, utilizing existing metering infrastructure to facilitate inter-temporal water banking and cross-sectoral reallocation.
Research Paper
Morteza Shokri; Ali Gholami
Abstract
The discharge of sloped piano key weirs (PKWs) is proportionate to the upstream head, which allows for improving hydraulic performance under various conditions. This study experimentally investigates the discharge coefficient and hydraulic performance of sloped and non-sloped PKWs with rectangular and ...
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The discharge of sloped piano key weirs (PKWs) is proportionate to the upstream head, which allows for improving hydraulic performance under various conditions. This study experimentally investigates the discharge coefficient and hydraulic performance of sloped and non-sloped PKWs with rectangular and trapezoidal sections. The goal was to evaluate the effects of the crest slope of sidewalls on the discharge coefficient and performance of a PKW. Tests were performed in an experimental flume with a length of 15 m and a height of 60 cm. Rectangular and trapezoidal type-A PKWs with 0° and 15° inclinations were studied. This study also incorporated the effect of the Weber number on the discharge coefficient of PKWs by evaluating hydraulic data. It was found that sloped rectangular and trapezoidal PKWs, where over 75% of the crest length contributed to the discharge, had larger discharge coefficients than their non-sloped counterparts. Moreover, in light of their larger effective length, sloped trapezoidal PKWs had a 13% greater discharge coefficient than sloped rectangular PKWs on average. This suggests that sloped PKWs could improve flood management and water storage efficiency.
Research Paper
Hassan Koohestani; Ali Balooch
Abstract
The present study outlines the production of AgNPs through a green synthesis method utilizing the water extract of Ferula assa-foetida leaves. In contrast to earlier studies that mainly focused on the plant's gum, this research used an ultrasonic-assisted extraction method for the leaf tissues. FTIR ...
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The present study outlines the production of AgNPs through a green synthesis method utilizing the water extract of Ferula assa-foetida leaves. In contrast to earlier studies that mainly focused on the plant's gum, this research used an ultrasonic-assisted extraction method for the leaf tissues. FTIR analysis validated the presence of different organic compounds, particularly phenolic groups, on the AgNPs surface, which is crucial for their stability and bioactivity. FE-SEM images displayed the nanoparticles' shapes, which were mainly spherical and cauliflower-like, with an average size of 86 nm. XRD analysis revealed that silver ions were reduced to create metallic nanoparticles in the following phase, as shown by distinctive peaks at 38.2°, 44.4°, and 64.51°. Synthesized nanoparticles were assessed for antibacterial properties against two bacterial models: Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative). A higher sensitivity was observed in Gram-positive bacteria. Therefore, AgNPs produced using Ferula leaf extract can be considered valuable alternatives for antibacterial and therapeutic purposes.
Research Paper
Azar Asadi; Soheila Hamidi; Samin Sedaghatfard; Hadi Naderi
Abstract
This study presents a direct comparative and synergistic investigation of polyvinylpyrrolidone (PVP) and trimesic Acid (TMA) as additives for polyethersulfone (PES) membranes. Scanning electron microscopy (SEM) analysis revealed that PVP primarily acts as a pore-forming agent, while TMA induces a finer, ...
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This study presents a direct comparative and synergistic investigation of polyvinylpyrrolidone (PVP) and trimesic Acid (TMA) as additives for polyethersulfone (PES) membranes. Scanning electron microscopy (SEM) analysis revealed that PVP primarily acts as a pore-forming agent, while TMA induces a finer, sponge-like morphology. Water contact angle (WCA) measurements confirmed that TMA imparts higher surface hydrophilicity (37.5°) compared to PVP, attributed to its lower aqueous solubility and greater retention of hydrophilic carboxylic acid groups within the polymer matrix. Pure water flux (PWF) data, monitored at 4 bar pressure, showed that membranes embedded with TMA as a single additive had lower flux than the bare membrane, due to their sponge-like pore structure. A powerful synergistic effect was discovered in dual-additive formulations. The optimal membrane (M7), containing 1 wt.% each of PVP and TMA, achieved an exceptional PWF of 103 kg/m²·h. This synergy is driven by accelerated co-leaching during phase inversion, which optimizes pore structure. From the antifouling test, single TMA-based membranes demonstrated the highest FRR values (approximate 100%). Meanwhile, the membranes containing both PVP and TMA showed compromised FRR. Nevertheless, M7 membrane maintained an acceptable FRR of 75%. The results indicate that combining PVP and TMA creates a synergistic effect, producing membranes with a superior balance of high permeability and antifouling resistance compared to those with a single additive.
