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This review paper examines the prior studies on critical factors of e-learning adoption in Pakistan. The search terms identified 40 papers reporting 25 conceptual and qualitative and 15 quantitative evidence about the e-learning adoption and critical factors that may influence the adoption of e-learning in Pakistan. The findings revealed that modern paradigm shift requires the in-depth analysis of government policies, institutional and management role, students and faculty attitude, social norms, cultural values as well as technological advancement. These factors may directly or indirectly affect the intention of students towards e-learning adoption. The lack of quantitative evidences illustrate that policy makers, practitioners and researchers need to pay attention for further research of identifying and analyzing the critical factors which enhances the e-learning adoption in Pakistan.

Abstract As the number of passengers at border entry points such as airports and rail stations increases, so does the demand for seamless, secure, and fast biometric technologies for verification purposes. Although fingerprints are currently useful biometric technologies, they are intrusive and slow down the end-to-end verification process, increasing the chances of tampering. Emerging as an alternative technology, soft biometrics have proven successful for non-intrusive and rapid verification. Soft biometrics consists of a large set of features from three different modalities of the human body, including the face, body, and essential & auxiliary attachments. This paper proposes a multi-channel soft biometrics framework that leverages soft biometrics technology over traditional biometrics. The framework encapsulates four distinct components: ApparelNet, which verifies essential and auxiliary attachments; A-Net, which measures anthropometric soft biometrics; OneDetect, which predicts global soft biometrics; and RSFS, which develops a set of highly relevant and supportive soft biometrics for verification. The proposed framework addresses several critical limitations of existing biometrics technologies during the verification process at border entry points, such as intrusive behavior, response time, biometric tampering, and privacy issues. The proposed multi-channel soft biometrics framework has been evaluated using several benchmark datasets in the field, such as Front-view Gait (FVG), Pedestrian Attribute Recognition At Far Distance (PETA), and Multimedia and Vision (MMV) Pedestrian. Using heterogeneous datasets enables the testing of each framework component or channel against numerous constrained and unconstrained scenarios. The outcome of the envisioned multi-channel soft biometrics framework is presented based on distinct outcomes from each channel, but it remains focused on determining a single cumulative verification score for verification at border control. In addition, this multi-channel soft biometrics framework has extended applications in several fields, including crowd surveillance, the fashion industry, and e-learning.

Microalgae cultivation has received much interest in foods and biofuel production and provides a significant potential option for cleaning the soil, water, and environment from several contaminants. Accordingly, microalgae harvesting becomes essential to separate the solid–liquid microalgae suspension for other green technologies and sustainable processes. Although several physical, chemical, and physiochemical methods have been widely used for microalgae harvesting, their cost, non-environmental residues, and harvesting efficiencies are still questionable. This review summarized and evaluated the performance of different natural coagulants used for harvesting cultivated microalgae. The operational factors and their effect on harvesting efficiency were discussed. Moreover, the current challenges in utilizing several natural coagulants in microalgae harvesting were considered. HIGHLIGHTS Microalgae harvesting is a major key to microalgae-based biofuel production.; Microalgae can be used to separate solid-liquid microalgae suspensrion.; The optimal removal for microalgae can be obtained at pH ranging between 5 and 9.;

The long-term sustainability of the global water supply, with a paramount emphasis on cleanliness and safety, stands as a formidable challenge in our modern era. In response to this pressing issue, adsorption techniques have emerged as pivotal and widely recognized solutions for the removal of hazardous pollutants, with a particular emphasis on lead adsorption from wastewater. This comprehensive review explores the relentless advancements made in the adsorption domain, highlighting innovations using separation and purification techniques that surpass traditional metal oxide-based adsorbents. Of particular note is the growing exploration of alternative materials, such as starch, chitosan, nanoscale structures like zeolites and metal-organic frameworks, magnetic materials, and carbon-based substances for the development of inorganic adsorbents. These materials, with their remarkable capacity for nanoscale structural adjustment, possess extraordinary capabilities for effective contaminant removal, facilitating swift water purification. The literature survey for this review was conducted using the Google Scholar engine, with “adsorbents for lead remediation” as the starting keywords, resulting in approximately 6000 papers. The search was refined to focus on the last three years and specifically targeted review papers which are most relevant to lead remediation. More than 100 papers were analysed to investigate various techniques, surface modifications, and adsorbent materials for managing inorganic pollutants in water. This review also illuminates research limitations, with a specific focus on starch-based adsorbents in lead remediation. As we progress towards practical commercial applications, this review identifies challenges associated with the development of inorganic adsorbents and provides invaluable insights into future prospects. Surface modification emerges as a promising path, with the potential to substantially enhance adsorption capacity, potentially doubling or even quadrupling it. Moreover, the adsorbents demonstrate impressive regenerative capabilities, maintaining up to 90% regeneration efficiency after multiple cycles. In conclusion, starch-based adsorbents show considerable potential as effective agents for lead purification from aquatic environments. Nevertheless, the need for further research persists, emphasizing the optimization of the adsorption process and exploring the long-term stability of starch-based adsorbents in real-world scenarios.

Municipal solid waste management (SWM) is one of the most useful applications of renewable energy, supporting the market for renewable energy and assisting in environmental protection by reducing emissions. Sustainability is one of the key issues with solid waste management systems in developing countries, including Palestine. Waste-to-energy (WTE) technology is one of the greatest strategies for effectively managing solid waste. This study focuses mostly on waste management in Palestine’s Tulkarm area. We conducted an evaluation of the potential of energy recovery from municipal solid waste through a number of approaches, such as incineration, gasification, anaerobic digestion, and landfilling. Additionally, the implications on the environment, human health, and economics were investigated. The results showed that anaerobic digestion recovered around 5156.15 kWh per day; whereas, incineration and gasification recovered about 40,986.60 and 14,663.88 kWh per day, respectively. The least recovered energy amount was roughly 3563.87 kWh per day, which was generated by landfilling technology. Additionally, the environmental analysis showed that anaerobic digestion could save around 48,362 tons of CO2 annually; meanwhile, incineration and gasification could save about 384,424 and 137,538 tons of CO2, respectively. The lowest quantity of emissions could be saved by landfilling, with about 33,427 tons saved yearly. The energy cost savings associated with each technology were also estimated. The results of the energy savings estimation showed that incineration had the highest saving of USD 4918.12; gasification and anaerobic digestion saved USD 1759.67 and USD 618.74, respectively. Whereas, landfilling had the lowest saving of about USD 427.66. A careful analysis of all aspects related to each technology, in comparison to the available waste treatment techniques, was carried out to propose a solution to cover the energy deficit in Tulkarm as a primary goal. Anaerobic digestion was found to be more environmentally advantageous and economically feasible and thus can be recommended to decision-makers and investors.

Recovery of wastewater is essential for better management of water resources and can aid in reducing regional or seasonal water shortages. When algae were used to clean wastewater, amazing benefits were guaranteed, such as a decrease in the formation of dangerous solid sludge and the creation of valuable algal biomass through recycling of the nutrients in the wastewater. The trace elements nitrogen, phosphorus, and others that microalgae need for cell development are frequently present in contaminated wastewater. Hence, microalgal bioremediation is used in this study as an effective technique for the simultaneous treatment of COD, NH3-N, and orthophosphate from domestic wastewater and biomass production. Different concentrations of wastewaters were used. The maximum removals attained were: 84% of COD on the fifth day using the lowest mixing ratio of 50%, 95% of ammoniacal nitrogen, and 97% of phosphorus. The highest biomass production was achieved at day 12, except for the mixing ratio of 80% where the growth rate increased until day 14 at 400 mg/L.

Emerging contaminants (ECs) usually refer to pesticides, polycyclic aromatic hydrocarbons (PAHs), dioxins, personal care products, cosmetics, and medications. Due to the strong demand and quick growth of these businesses, the ECs have continuously been found in alarming amounts in groundwater, surface water, and wastewater. These ECs provide a significant non-esthetic threat to the ecosystem as a whole and can cause significant non-esthetic contamination when released into the aquatic environment. The conventional wastewater treatment techniques such as activated sludge, membrane filtration, coagulation, adsorption, and ozonation showed ECs removal performance to a certain extent. In turn, numerous emerging advanced oxidation processes (AOPs), especially activated persulfate oxidation, have garnered a huge amount attention due to their outstanding performance in the remediation of ECs. This article presents a systematic and critical review of electro, sono and thermal activation of persulfate for the treatment of ECs. The effect of key parameters such as electrode materials, solution pH, persulfate concentration, current density, and temperature on electro, sono- and thermal-activated degradation of ECs was discussed. The possible reaction mechanism of ECs degradation was also elucidated in detail. It was closed with a note on the situation now and the future course of electro, sono and thermal activation in ECs degradation applications. Experiments performed in recent studies show that with the aid of persulfate in electro activation, the removal efficiency of chemical oxygen demand can be achieved up to 72.8%. Persulfate activated by sono shows 100% removal efficiency of 1,1,1-trichloroethane and sulfamethoxazole. While for thermal activation of persulfate, 100% removal efficiency of carbamazepine, atrazine and sulfamethazine was achieved. All these vital shreds of evidence are substantial enough to picture the negative impact of ECs on the environment.

The process of looking for alternative energy sources is driven by the increasing demand for energy and environmental contamination caused by using fossil fuels. Recent investigations reported the efficiency of microalgae for biofuel production due to its low cost of production, high speed of growth, and ability to grow in harsh environments. In addition, many microalgae are photosynthetic, consuming CO2 and solar light to grow in biomass and providing a promising bioenergy source. This review presents the recent advances in the application of microalgae for biofuel production. In addition, cultivation and harvesting systems and environmental factors that affect microalgae cultivation for biofuel production have also been discussed. Moreover, lipid extraction and conversion technologies to biofuel are presented. The mixotrophic cultivation strategy is promising as it combines the advantages of heterotrophy and autotrophy. Green harvesting methods such as using bio-coagulants and flocculants are promising technologies to reduce the cost of microalgal biomass production. In the future, more investigations into co-cultivation systems, new green harvesting methods, high lipids extraction methods, and the optimization of lipid extraction and converting processes should be implemented to increase the sustainability of microalgae application for biofuel production.

Restaurant wastewater contains a high concentration of O&G, up to 3434 mg/L. This study aims to (a) assess the efficiency of EC combined with US methods for O&G removal in restaurant wastewater, (b) identify the optimum condition for COD degradation using EC treatment via response surface methodology (RSM), and (c) determine the morphological surface of the aluminium (Al) electrode before and after EC treatment. The wastewater samples were collected from the Lembaran cafeteria at the Universiti Sains Malaysia (USM). The efficiency of EC, US, and US-EC, combined methods for O&G removal, was investigated using a batch reactor (pH 7). The interelectrode distance (ID, 2–6 cm), electrolysis time (T, 15–35 min), and current density (CD, 40–80 A/m2) were analysed, followed by RSM. The response variables were O&G (1000 mg/L) and chemical oxygen demand (COD low range, 1000 mg/L). The central composite design (CCD) with a quadratic model was used to appraise the effects and interactions of these parameters. The morphological surface of the electrode used was observed via scanning electron microscopy (SEM). The optimum removal efficiencies obtained were 95.4% (O&G) and 75.9% (COD) (ID: 2.4 cm, T: 30.5 min, and CD: 53.2 A/m2). The regression line fitted the data (R2 O&G: 0.9838, and R2 COD: 0.9558). The SEM images revealed that the use of US was useful in minimising cavitation on the electrode surface, which could lower the EC treatment efficacy. The US-EC combined technique is highly recommended for O&G removal from the food industry’s wastewater.

Algae have the potential to be used as a feedstock for the synthesis of valuable compounds and biofuels. In addition, algal waste can be further transformed into biofuel, biogas, and biochar using different thermochemical processes such as microwave pyrolysis, pyrolysis, torrefaction, and hydrothermal conversion. Due to its high specific surface area, rapid electron transport, and graphitic carbon structure, algal biochar carbonized at high temperatures has shown outstanding performance for applications as CO2 adsorbents, supercapacitors, and persulfate activation. Due to the combination of various functional groups and porous structures, the algae biomass pyrolysis at a moderate temperature produced high-quality biochar that shows high performance in terms of pollutant removal, while low-temperature pyrolysis produces coal fuel from algae via torrefaction. Over time, there have been exponentially more petroleum-based polymers created that have harmful impacts on both humans and the environment. As a result, researchers are becoming more interested in algae-based biopolymers as a potential alternative strategy for establishing a sustainable circular economy globally. The advantages of microalgal biopolymer over other feedstocks are its capacity to compost, which provides greenhouse gas credits, its quick growth ability with flexibility in a variety of settings, and its ability to minimize greenhouse gas emissions.

The most fundamental need, which all people must have to maintain their life, is access to clean water [...]

Advanced treatment of biologically processed palm oil mill effluent (BIOTPOME), which possesses a potential danger to the water sources is required to meet the Malaysian discharge standard, as BIOTPOME contains high level of chemical oxygen demand (COD), suspended solids and oil and grease even after going through conventional treatment process. The significant but insufficient treatment efficiency of ponding system in Malaysia urged an alternative method to treat the recalcitrant organic compounds. Thus, post-treatment of BIOTPOME using oxidation by thermally activated persulfate process was proposed to solve this issue. In order to maximize the removal of COD and color, the central composite design (CCD) module of the response surface approach was used to optimize the interactions of the process variables temperature, S2O82−/COD ratio, and reaction time. In order to identify the significant terms of interacting process factors, CCD performed a batch study from which statistical models of responses were created. All models were confirmed by analysis of variance (ANOVA) showing significances with Prob > F less than 0.1. The optimal performance was obtained at the temperature of 67.4 °C, S2O82−/COD ratio of 9.8 and reaction time of 120 min, rendering COD removal of 85.65% and color removal of 85.74%. The total cost for the treatment process was RM0.94 per liter.

In this work, SiO2 nanoparticles were prepared by the sol-gel method after sodium silicate was extracted from rice husk ash (RHA) under various experimental conditions such as types of acids, NaOH concentration, dissolved time, and temperature and used for removal of Fe2+ ions from aqueous solutions. The extracted SiO2 was morphologically and chemically characterized and showed a surface area of 78 m2/g and uniform pores of 2.71 nm, offering high adsorption capacity for Fe2+ ions. The influence of pH, contact time, and amount of adsorbent was studied in order to establish the best conditions for the Fe2+ adsorption and removal. Furthermore, the adsorption data were fitted with an exponential shape curve for all the three variable parameters that affect the adsorption process. The best results were obtained for pH 5, 20 min contact time, and 0.5 g adsorbent dose. The loading adsorption capacity was 9 mg of Fe2+ ions/g SiO2 in the concentration range 0.1–1.0 mgL−1. In addition, the synthesized SiO2 with the size of around 50 nm can be used for specific heavy metal removal and drug delivery, after modification of the SiO2 surface with various functional groups.

This review presents the extractions, characterisations, applications and economic analyses of natural coagulant in separating pollutants and microalgae from water medium, known as microalgae harvesting. The promising future of microalgae as a next-generation energy source is reviewed and the significant drawbacks of conventional microalgae harvesting using alum are evaluated. The performances of natural coagulant in microalgae harvesting are studied and proven to exceed the alum. In addition, the details of each processing stage in the extraction of natural coagulant (plant, microbial and animal) are comprehensively discussed with justifications. This information could contribute to future exploration of novel natural coagulants by providing description of optimised extraction steps for a number of natural coagulants. Besides, the characterisations of natural coagulants have garnered a great deal of attention, and the strategies to enhance the flocculating activity based on their characteristics are discussed. Several important characterisations have been tabulated in this review such as physical aspects, including surface morphology and surface charges; chemical aspects, including molecular weight, functional group and elemental properties; and thermal stability parameters including thermogravimetry analysis and differential scanning calorimetry. Furthermore, various applications of natural coagulant in the industries other than microalgae harvesting are revealed. The cost analysis of natural coagulant application in mass harvesting of microalgae is allowed to evaluate its feasibility towards commercialisation in the industrial. Last, the potentially new natural coagulants, which are yet to be exploited and applied, are listed as the additional information for future study.

This study examines the suitability of natural silica sand as a low-cost adsorbent for the removal of ammoniacal nitrogen and heavy metals, particularly iron and zinc, from semi-aerobic stabilized landfill leachate. Leachate samples were collected from the Pulau Burung landfill site (PBLS) in Penang, Malaysia. The above-mentioned contaminants are highlighted in this study because of their unsafe concentrations at PBLS. The effects of shaking time, settling time, and silica sand dosage on the study parameter removal efficiencies were investigated to predict the performance of the process. The adsorptions of ammoniacal nitrogen, iron, and zinc were judiciously described by Langmuir and Freundlich isotherm models. The optimum removal efficiencies of ammoniacal nitrogen, iron, and zinc obtained were 51%, 44.4%, and 39.2%, respectively, with a shaking time of 90 min, a settling time of 60 min, and with a dosage of 60 g (0.5 kg/L) of silica sand. Based on the coefficient of determination (R2) values obtained from Langmuir and Freundlich isotherm models, ammoniacal nitrogen, iron, and zinc adsorption were better fitted to the Freundlich model.

The data on 575 records of 270 Holstein Friesian and 818 records of 326 Jersey cows maintained in Punjab, Pakistan were analyzed. The cows were grouped into imported Holstein Friesian, imported Jersey, Farm born Holstein Friesian and farm born Jersey cows. Lactation milk yield of farm born Holstein Friesian and Jersey cows was significantly (P

The visible-light-driven photocatalytic degradation of Bisphenol A (BPA) was investigated using the binary composite of alkaline treated g-C3N4 (HT-g-C3N4) deposited over commercial TiO2 (Evonik Degussa GmbH, Essen, Germany). The existence and contribution of both TiO2 and g-C3N4/HT-g-C3N4 in the composite was confirmed through various analytical techniques including powder X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy (FESEM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible diffuse reflectance spectra (UV-vis-DRS), and photoluminescence (PL) analysis. The results showed that the titania in the binary composite exhibited both pure rutile and anatase phases. The morphological analysis indicated that the spongy “morel-like” structure of g-C3N4 turned to nanotube form after alkaline hydrothermal treatment and thereby decreased the specific surface area of HT-g-C3N4. The low surface area of HT-g-C3N4 dominates its promising optical property and effective charge transfer, resulting in a deprived degradation efficiency of BPA two times lower than pure g-C3N4. The binary composite of HT-g-C3N4/TiO2 exhibited excellent degradation efficiency of BPA with 2.16 times higher than the pure HT-g-C3N4. The enhanced photocatalytic activity was mainly due to the promising optical band gap structure with heterojunction interface, favorable specific surface area, and good charge separation.