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20 pages, 17549 KB  
Article
Divergent Compositions and Biogeochemical Pathways of Dissolved Organic Matter in a Monsoon-Affected Coastal Aquifer: Insights from Molecular Characterization
by Ashen Randika, Samadhi Athauda, Ruizhe Wang, Zhineng Hao, Yuansong Wei, Yawei Wang, Hui Zhong, Madhubhashini Makehelwala, Sujithra K. Weragoda and Rohan Weerasooriya
Hydrology 2026, 13(5), 120; https://doi.org/10.3390/hydrology13050120 - 28 Apr 2026
Viewed by 680
Abstract
Coastal groundwater in monsoon-dominated regions faces compounding threats from seasonal hydrological extremes and seawater intrusion (SWI), yet the molecular-scale response of dissolved organic matter (DOM) remains poorly understood. We conducted a two-season investigation in Mannar District, Sri Lanka, integrating hydrochemistry, fluorescence spectroscopy, and [...] Read more.
Coastal groundwater in monsoon-dominated regions faces compounding threats from seasonal hydrological extremes and seawater intrusion (SWI), yet the molecular-scale response of dissolved organic matter (DOM) remains poorly understood. We conducted a two-season investigation in Mannar District, Sri Lanka, integrating hydrochemistry, fluorescence spectroscopy, and Fourier-transform ion cyclotron resonance mass spectrometry to characterize DOM dynamics across shallow and deep groundwater. Dry-season chloride averaged 302 mg/L (shallow—5 to 12 m) and 505 mg/L (tube wells—20 to 30 m), then declined by 60–80% during monsoon recharge. Despite this freshening, DOM dynamics were decoupled from salinity: shallow wells showed dry-season DOC peaks (6.64 mg/L) driven by soil concentration, while tube wells exhibited wet-season enrichment (5.02 mg/L). Shallow aquifers maintained consistently high humification indices (around 0.70) and aromatic-rich DOM, indicating sustained buffering by soil-derived inputs. In contrast, wet-season recharge in tube wells appeared to stimulate microbial processing, as indicated by elevated protein-like fluorescence (C2: 26% to 36%) and a higher contribution of nitrogen-bearing formulas (CHONs: 31.4% to 37.1%). Tube wells also accumulated reduced, energy-rich DOM with correspondingly high molecular lability indices. Paradoxically, correlation networks suggested that these saturated aliphatic and halogenated structures persist due to kinetic protection under low oxygen, high-salinity conditions. These findings indicate that aquifer structure and redox conditions control DOM biogeochemistry in coastal groundwater systems. At the molecular level, DOM dynamics are influenced by aquifer depth and seasonal recharge, leading to a decoupling between salinity and organic matter transformation. Full article
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15 pages, 779 KB  
Article
The Prevalence of Environmental Claims and Recycling Information on Alcohol Products
by Laura Bathie, Asad Yusoff, Paula O’Brien, Samadhi Hemachandra, Bella Sträuli, Michelle I. Jongenelis, Jacquie Bowden and Simone Pettigrew
Sustainability 2026, 18(2), 800; https://doi.org/10.3390/su18020800 - 13 Jan 2026
Viewed by 1264
Abstract
Greenwashing by unvalidated environmental labelling is increasingly common and highly problematic due to the potential to mislead consumers. This is especially concerning for products that pose health risks, including alcohol. As environmental sustainability becomes more important to consumers, it is vital to assess [...] Read more.
Greenwashing by unvalidated environmental labelling is increasingly common and highly problematic due to the potential to mislead consumers. This is especially concerning for products that pose health risks, including alcohol. As environmental sustainability becomes more important to consumers, it is vital to assess changes in the use of potentially misleading claims over time. Among the first studies of its kind globally, this study aimed to (i) develop a typology of environmental claims displayed on alcohol products in Australia, (ii) examine the prevalence of these claims to establish baseline data for ongoing tracking, and (iii) assess the provision of recycling information. Four claim categories were identified: sustainability, planet friendly, bio-related and carbon-related. Claims featured on 8% of the 5982 sampled products, with considerable variation between alcohol categories. Sustainability claims were the most prevalent (5%). Recycling information appeared on 72% of products. The results suggest ambiguous environmental claims are present although not yet widespread. In contrast, recycling information is much more common although not universal. These findings highlight the need to consider restrictions on unsubstantiated environmental claims on alcohol products that can mislead consumers. Further, a nationally standardised mandatory recycling label should be introduced to assist consumers in reducing their environmental impacts. Full article
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17 pages, 1577 KB  
Article
Methanolic Extract of Moringa oleifera Seed Synergizes the Bactericidal Effect of Ampicillin, Cephalexin, and Amoxicillin/Clavulanic Acid Against Multidrug-Resistant Escherichia coli Isolated from Street-Vended Food
by Daniela Mora-Coto, Pedro R. Moreno-Vélez, José Luna-Muñoz, José Jaime Jarero-Basulto, Anahi Pérez-Galicia, Samadhi Moreno-Campuzano and Miguel Angel Ontiveros-Torres
Microbiol. Res. 2025, 16(11), 238; https://doi.org/10.3390/microbiolres16110238 - 12 Nov 2025
Viewed by 1292
Abstract
Background: Antibiotic drug resistance is a serious global health problem that threatens therapeutics against infectious diseases. As antibiotics become less effective every year, our objective was to evaluate the adjuvant activity of methanolic extracts of Moringa oleifera seed combined with antibiotics of clinical [...] Read more.
Background: Antibiotic drug resistance is a serious global health problem that threatens therapeutics against infectious diseases. As antibiotics become less effective every year, our objective was to evaluate the adjuvant activity of methanolic extracts of Moringa oleifera seed combined with antibiotics of clinical use against multidrug-resistant Escherichia coli isolated from street food samples searching for a new alternative to treat infectious diseases commonly treated with antibiotics. Methods: Secondary metabolites of M. oleifera seeds were obtained through maceration (methanol 80%) and detected following qualitative phytochemical assays. MIC, MBC and tolerance level were determined using microdilution tests. Antimicrobial activity was tested by sensitivity analysis, and the adjuvant activity was explored in combination with twelve antibiotics against the E. coli samples. Results: Alkaloids, phenolic compounds, flavonoids, and polyphenols were detected. MIC and MBC values ranged from 31.3 to 62 mg/mL and 62–125 mg/mL, respectively. The extract showed low antimicrobial activity against the multidrug-resistant E. coli, but the inhibitory capacity of ampicillin, cephalexin, and amoxicillin/clavulanic acid was significantly increased when combined with the plant extract. In contrast, the activity of ciprofloxacin, levofloxacin, tetracycline, polymyxin, and nalidixic acid decreased with the extract. Conclusion: Methanolic extracts of M. oleifera seeds represent a potential adjuvant for beta-lactams in the face of the growing problem of global antimicrobial resistance. This study represents the first steps in exploring the adjuvant capacity of plants against resistant environmental pathogens in Mexico. Full article
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12 pages, 446 KB  
Article
Sustainability Implications of Changes in Types and Variability of Yoghurt Packaging Solutions over a Decade
by Samadhi Hemachandra and Simone Pettigrew
Sustainability 2025, 17(18), 8273; https://doi.org/10.3390/su17188273 - 15 Sep 2025
Viewed by 1595
Abstract
Packaging configurations have variable environmental impacts, making it essential to assess changes over time, particularly for high-impact food categories such as dairy. This study examined yoghurt packaging in Australia between 2013 and 2023, focusing on sustainability implications. Analyses of products from major retailers [...] Read more.
Packaging configurations have variable environmental impacts, making it essential to assess changes over time, particularly for high-impact food categories such as dairy. This study examined yoghurt packaging in Australia between 2013 and 2023, focusing on sustainability implications. Analyses of products from major retailers (n = 315 in 2013; n = 454 in 2023) assessed (i) the number and type of packaging configurations, (ii) prevalence of serving and pack sizes, and (iii) packaging features affecting food waste. Packaging types were classified by container and film composition. The number of configuration categories increased from 16 to 19, reflecting greater diversity in packaging solutions. Nearly half of single-serve products in both years featured resealable packaging, despite being intended for one-time consumption, suggesting potential over-packaging. The rise in pouch packaging raises concerns about reduced emptiability, which may contribute to increased food waste. These findings demonstrate how packaging changes over the decade have introduced sustainability trade-offs. Monitoring such changes can inform strategies to reduce waste and improve the environmental performance of packaging solutions for environmentally intensive products, such as yoghurts. Full article
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12 pages, 637 KB  
Proceeding Paper
Enhancing Cognitive and Metacognitive Domains of Autistic Children Using Machine Learning
by Dilmi Tharaki, Yashika Rupasinghe, Piyathma Ruhunage, Ama Pehesarani and Samadhi Chathuranga Rathnayake
Eng. Proc. 2025, 107(1), 9; https://doi.org/10.3390/engproc2025107009 - 21 Aug 2025
Viewed by 2590
Abstract
ASD poses special difficulty in both cognitive and metacognitive development, necessitating specialized educational strategies. This research proposes LearnMate, a web-based application powered by machine learning techniques that aims to improve the abilities of children with autism. Utilizing classification models learned from medical data, [...] Read more.
ASD poses special difficulty in both cognitive and metacognitive development, necessitating specialized educational strategies. This research proposes LearnMate, a web-based application powered by machine learning techniques that aims to improve the abilities of children with autism. Utilizing classification models learned from medical data, LearnMate forecasts skill acquisition and suggests personalized learning activities according to the strengths and developmental requirements of the child. The system permits instructors to monitor progress through real-time feedback, enabling adaptive learning approaches. Pilot application to more than 100 children showed significant gains in their skills. The results demonstrate the immense potential for change through machine learning in special education to facilitate data-driven, personalized learning opportunities that enhance the capabilities of both autistic students and teachers. Full article
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18 pages, 3595 KB  
Article
Intestinal and Extraintestinal Pathotypes of Escherichia coli Are Prevalent in Food Prepared and Marketed on the Streets from the Central Zone of Mexico and Exhibit a Differential Phenotype of Resistance Against Antibiotics
by Daniela Mora-Coto, Pedro Moreno-Vélez, José Luna-Muñoz, Samadhi Moreno-Campuzano and Miguel Angel Ontiveros-Torres
Antibiotics 2025, 14(4), 406; https://doi.org/10.3390/antibiotics14040406 - 16 Apr 2025
Cited by 3 | Viewed by 3459
Abstract
Background/Objectives: Antibiotic resistance is a serious public health problem threatening the treatment of infectious diseases caused by Escherichia coli, the main source of food contamination and responsible for many infectious diseases with high indices of AR profiles. Our objective was to study [...] Read more.
Background/Objectives: Antibiotic resistance is a serious public health problem threatening the treatment of infectious diseases caused by Escherichia coli, the main source of food contamination and responsible for many infectious diseases with high indices of AR profiles. Our objective was to study the presence of Escherichia coli in foods that are distributed and prepared on the street, characterizing its sensitivity profile and resistance to antibiotic drugs commonly prescribed in this geographical area. Methods: Standard procedures were performed to identify and isolate E. coli colonies from food samples collected during a three-year study. Susceptibility assays were conducted to determine the antibiotic resistance profile, and Colony PCR assays were performed to determine the pathogenic and antibiotic resistance genes. Results: A total of 189 food samples were collected, and 100% of the samples were positive for E. coli, with higher percentages of contamination for vegetables and fruits. ETEC (lt) and UPEC (vat, cnf1, hylA) genes were identified in 100% of the samples and DAEC (afa) in 27%. E. coli exhibited high percentages of resistance against ampicillin and amoxicillin/clavulanic acid (100%) and cephalexin (45%). The most effective antibiotics were tetracycline, TMP-SMX, polymyxin, and quinolones. The AR genes tetA, sul1, catA1, strA, qnrS, and floR were identified among the samples. Conclusions: Food prepared and marketed on the streets seriously threatens human health. Ampicillin and amoxicillin/clavulanic acid should not be used to treat infections caused by the multidrug-resistant ETEC and UPEC identified in this area. To our knowledge, this is the first study that explores the status of AR in this geographical area. Full article
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17 pages, 383 KB  
Article
’Srī Gurugītā: A Sanskrit Devotional Text and Musical Yogic Practice
by Brita Renée Heimarck
Religions 2024, 15(8), 894; https://doi.org/10.3390/rel15080894 - 25 Jul 2024
Cited by 1 | Viewed by 2776
Abstract
This article investigates the Sanskrit hymn, ´Srī Gurugītā, from a scholarly, scriptural, historical, and ethnographic standpoint. Mystical yogic concepts such as chaitanya-shabda (Consciousness–sound) and shravana samadhi (absorption through reading or listening to holy texts) are introduced in the context of Gurugītā recitation. [...] Read more.
This article investigates the Sanskrit hymn, ´Srī Gurugītā, from a scholarly, scriptural, historical, and ethnographic standpoint. Mystical yogic concepts such as chaitanya-shabda (Consciousness–sound) and shravana samadhi (absorption through reading or listening to holy texts) are introduced in the context of Gurugītā recitation. The history of diverse lineages that practice Gurugītā recitation and several historical dimensions of svadhyaya (long-text chanting) and namasankirtana (short chants) are briefly introduced, and the works of Jeremy Morse and Antonio Rigopoulos are closely considered. This article deals with the significant elements of yogic awakening referenced within the Gurugītā text and the goal of liberation cited therein. Many scholars have researched Hinduism, Tantra, Bhakti yoga, and devotion. This article investigates musical devotion in the context of yogic communities dedicated to Gurugītā recitation with the aim of experiencing the inner Self. The democratization and dissemination of this practice have global dimensions. Full article
(This article belongs to the Special Issue Musicology of Religion: Selected Papers on Religion and Music)
15 pages, 17599 KB  
Article
Geochemical Assessment of the Evolution of Groundwater under the Impact of Seawater Intrusion in the Mannar District of Sri Lanka
by Samadhi Athauda, Yunwen Wang, Zhineng Hao, Suresh Indika, Isuru Yapabandara, Sujithra K. Weragoda, Jingfu Liu and Yuansong Wei
Water 2024, 16(8), 1137; https://doi.org/10.3390/w16081137 - 17 Apr 2024
Cited by 9 | Viewed by 3310
Abstract
Groundwater is an important drinking water resource in the coastal regions of island countries and has suffered from heavy seawater intrusion. However, the areas specifically affected by seawater intrusion and their groundwater hydrogeochemical compositions and evolution processes remain unclear. This study analyzed the [...] Read more.
Groundwater is an important drinking water resource in the coastal regions of island countries and has suffered from heavy seawater intrusion. However, the areas specifically affected by seawater intrusion and their groundwater hydrogeochemical compositions and evolution processes remain unclear. This study analyzed the hydrogeochemical compositions, water quality, and evolution processes of groundwater in the Mannar district, Sri Lanka, during the dry season. A total of 56 samples were collected from shallow wells and tube wells across the region, and about 64.28% of groundwater samples had good quality (WQI < 100). Geochemical compositions and water quality parameters had a high level in the north and south mainland regions, where they severely suffered from seawater intrusion with a high content of Cl and Na+. The geochemical compositions of groundwater in the Mannar district were predominantly affected by rock weathering and/or evaporation processes. Cl-Na and HCO3-Ca facies were the main hydrochemical types, and the corresponding ions were mainly from silicate and halite dissolution. The reverse cation exchange process mainly occurred in seawater intrusion areas. The study highlights the impacts of seawater intrusion on the hydrogeochemical compositions and evolution processes in Mannar region groundwater, which will enhance the understanding of the local water quality and seawater intrusion situation and aid in protecting drinking water safety by routinely monitoring the groundwater quality and implementing targeted desalination techniques in the key areas. Full article
(This article belongs to the Section Oceans and Coastal Zones)
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47 pages, 6991 KB  
Systematic Review
Interrelations of the Factors Influencing the Whole-Life Cost Estimation of Buildings: A Systematic Literature Review
by Herath Mudiyanselage Samadhi Nayanathara Samarasekara, Mahesh Babu Purushothaman and Funmilayo Ebun Rotimi
Buildings 2024, 14(3), 740; https://doi.org/10.3390/buildings14030740 - 9 Mar 2024
Cited by 10 | Viewed by 6606
Abstract
The global GDP has witnessed a significant upswing, majorly due to the growth of the construction industry. Embracing the whole-life costing (WLC) approach, the construction sector strategically manages expenses across a construction project’s life cycle. However, despite its widespread adoption, accurate cost forecasting [...] Read more.
The global GDP has witnessed a significant upswing, majorly due to the growth of the construction industry. Embracing the whole-life costing (WLC) approach, the construction sector strategically manages expenses across a construction project’s life cycle. However, despite its widespread adoption, accurate cost forecasting remains a major challenge. The intricate interplay of various influencing factors has not been fully explored, leading to inaccurate cost estimations. A comprehensive understanding of specific factors and their interrelationships is crucial to address this issue. Therefore, it is imperative to conduct further research to identify and explore the subtle nuances of these factors that impact whole-life cost estimation. Our study fills this gap, analysing 51 factors from 84 papers across prominent repositories. We assess interrelationships using a systematic literature review and pairwise comparison as in the analytical hierarchy process. The International Construction Measurement Standards (ICMS) framework structures these relationships and is represented in the causal loop diagrams (CLDs). The pioneering CLDs are a notable contribution, illustrating interrelationships and polarities among the 51 WLC factors. Six reinforcing loops and one balancing loop provide valuable insights into their dynamic nature. Importantly, lower-level factors do not always directly connect with upper-level factors. Instead, they interact within the same level before linking to top-level factors. These findings are significant for professionals, such as cost estimators, quantity surveyors and scholars, offering a comprehensive understanding of the WLC system. Full article
(This article belongs to the Section Architectural Design, Urban Science, and Real Estate)
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15 pages, 2463 KB  
Review
Recent Progress on Catalytic of Rosin Esterification Using Different Agents of Reactant
by Mardiah Mardiah, Tjokorde Walmiki Samadhi, Winny Wulandari, Aqsha Aqsha, Yohanes Andre Situmorang and Antonius Indarto
AgriEngineering 2023, 5(4), 2155-2169; https://doi.org/10.3390/agriengineering5040132 - 9 Nov 2023
Cited by 12 | Viewed by 8761
Abstract
Gum rosin is an important agricultural commodity which is widely used as a raw material for various industries. However, gum rosin has low stability, crystallizes easily, and tends to oxidize. This is due to carboxyl groups and conjugated double bonds in gum rosin’s [...] Read more.
Gum rosin is an important agricultural commodity which is widely used as a raw material for various industries. However, gum rosin has low stability, crystallizes easily, and tends to oxidize. This is due to carboxyl groups and conjugated double bonds in gum rosin’s structure. Therefore, to reduce these weaknesses, it is necessary to modify the rosin compound to achieve better stability via the esterification process. This paper surveys esterification agents such as glycerol, pentaerythritol, methanol, ethylene glycol, polyethylene glycol (PEG), allyl group, and starch Rosin ester. The product is used in the manufacture of pressure-sensitive adhesives, drug delivery, solder flux for electronic devices, as a plasticizer, and as a coating agent in fertilizers. In general, the esterification reaction between alcohols and carboxylic acids is very slow without a catalyst. Heterogeneous catalysts have the advantage of controlling size, structure, spatial distribution, surface composition, thermal-chemical stability, and selectivity. Among the catalysts for gum rosin esterification are ZSM-5, Fe3O4, ZnO, Calcium, TiO2, Kaolin, and Al2O3, among others. Different catalysts and esterification agents can produce various physical and chemical properties of rosin ester and will result in specific rosin ester products, such as glycerol ester, pentaerythritol ester, methyl ester, glycol ester, allyl ester, and acid starch-based rosin. Full article
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15 pages, 570 KB  
Article
Going beyond Mindfulness: How Concentration and Tranquility Commonly Co-Arising with Mindfulness Account for Mental Health
by Ryan M. K. Chan, Winnie W. S. Mak and Ben C. L. Yu
Int. J. Environ. Res. Public Health 2023, 20(8), 5470; https://doi.org/10.3390/ijerph20085470 - 11 Apr 2023
Cited by 7 | Viewed by 7992
Abstract
Concentration and tranquility usually co-arise with mindfulness during mindfulness practice and in daily life and may potentially contribute to mental health; however, they have rarely been studied in empirical research. The present study aimed to examine the relationship of concentration and tranquility with [...] Read more.
Concentration and tranquility usually co-arise with mindfulness during mindfulness practice and in daily life and may potentially contribute to mental health; however, they have rarely been studied in empirical research. The present study aimed to examine the relationship of concentration and tranquility with mindfulness and indicators of mental health. With no existing self-report measure assessing concentration and tranquility, the Concentration Scale and Tranquility Scale were first developed and validated. Items were developed based on the extant literature, rated by a group of experts, and selected according to their ratings. Exploratory factor analyses (EFA; n = 384) and confirmatory factor analyses (CFA; n = 384) were employed in separate samples of university students and community adults to establish the factor structure of both scales. Their construct validity was established in another similar sample (n = 333) by examining their correlations with variables including (a) concentration-related concepts, (b) tranquility-related concepts, (c) mindfulness-related concepts, and (d) perceived stress and psychological distress. The relationships between concentration, tranquility, mindfulness, perceived stress and psychological distress were then examined by hierarchical multiple regressions, both cross-sectionally and longitudinally. A single-factor structure was found by the EFA and confirmed by the CFA for both scales. Concentration and tranquility were significantly and positively associated with (a) attentional control and (b) mindfulness and nonattachment; and negatively associated with (c) irritability and (d) perceived stress and psychological distress. Concentration and tranquility were found to have a significant incremental value over the effect of mindfulness on indicators of mental health. Concentration and tranquility can incrementally explain mental health above and beyond the effect of mindfulness. Full article
(This article belongs to the Section Mental Health)
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13 pages, 1821 KB  
Article
In Situ Synthesis of Zero-Valent Iron-Decorated Lignite Carbon for Aqueous Heavy Metal Remediation
by Hasara Samaraweera, Samadhi Nawalage, R. M. Oshani Nayanathara, Chathuri Peiris, Tharindu N. Karunaratne, Sameera R. Gunatilake, Rooban V. K. G. Thirumalai, Jilei Zhang, Xuefeng Zhang and Todd Mlsna
Processes 2022, 10(8), 1659; https://doi.org/10.3390/pr10081659 - 21 Aug 2022
Cited by 13 | Viewed by 4308
Abstract
Lignite’s large abundance, physicochemical properties and low cost are attractive for industrial wastewater remediation. However, directly applying lignite for wastewater treatment suffers low efficiency. Here, we synthesize highly efficient zero-valent iron (ZVI)-decorated lignite carbon through the in-situ carbonization of a lignite and FeCl [...] Read more.
Lignite’s large abundance, physicochemical properties and low cost are attractive for industrial wastewater remediation. However, directly applying lignite for wastewater treatment suffers low efficiency. Here, we synthesize highly efficient zero-valent iron (ZVI)-decorated lignite carbon through the in-situ carbonization of a lignite and FeCl2 mixture for heavy metal removal. The effect of carbonization temperature on the morphology, structure and crystallite phases of ZVI-decorated lignite carbons (ZVI-LXs) was investigated. At an optimized temperature (i.e., 1000 °C), ZVI particles were found evenly distributed on the lignite matrix with the particles between 20 to 190 nm. Moreover, ZVI particles were protected by a graphene shell that was formed in situ during the carbonization. The synthesized ZVI-L1000 exhibited higher Cu2+, Pb2+ and Cd2+ stripping capacities than pristine lignite in a wide pH range of 2.2–6.3 due to the surface-deposited ZVI particles. The maximum Langmuir adsorption capacities of ZVI-L1000 for Cd2+, Pb2+ and Cu2+ were 38.3, 55.2 and 42.5 mg/g at 25 °C, respectively, which were 7.8, 4.5 and 10.6 times greater than that of pristine lignite, respectively. ZVI-L1000 also exhibited a fast metal removal speed (~15 min), which is ideal for industrial wastewater treatment. The pseudo-second-order model fits well with all three adsorptions, indicating that chemical forces control their rate-limiting adsorption steps. The reduction mechanisms of ZVI-L1000 for heavy metals include reduction, precipitation and complexation. Full article
(This article belongs to the Section Environmental and Green Processes)
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12 pages, 5432 KB  
Article
The Effect of Alkali Roasting Pretreatment on Nickel Extraction from Limonite Ore by Using Dissolved SO2-Air
by Winny Wulandari, Meiyer Marthen Kinda, Rahmaditha Murida and Tjokorde Walmiki Samadhi
Minerals 2020, 10(8), 701; https://doi.org/10.3390/min10080701 - 7 Aug 2020
Cited by 5 | Viewed by 5467
Abstract
Extraction of limonite ore using dissolved SO2–air is an alternative hydrometallurgical method for nickel recovery. This process is carried out at atmospheric pressure and is shown to have good selectivity of nickel over iron, but with a low recovery yield. The [...] Read more.
Extraction of limonite ore using dissolved SO2–air is an alternative hydrometallurgical method for nickel recovery. This process is carried out at atmospheric pressure and is shown to have good selectivity of nickel over iron, but with a low recovery yield. The literature refers to the application of alkali roasting as pretreatment in laterite ore leaching to increase nickel recovery. Thus, this study aims to apply the combination method of alkali roasting and leaching to extract nickel from limonite ore (1.33% Ni, 46.61% Fe) from the Southeast Sulawesi region. Three alkali compounds were included in the study (NaOH, Na2CO3 and Na2SO4). The batch-leaching process was carried out at pH 1 and 3 and temperatures of 55 and 80 °C for 180 min. The leach liquors were sampled at 15, 60, 90 and 120 min, and concentrations of the extracted metals were measured by Atomic Absorption Spectrometry (AAS). A mineralogy characterization of the raw ore and its residue after leaching was undertaken by using X-Ray Diffraction (XRD), while the thermal decomposition behavior of the ore was characterized by Thermogravimetry Analyzer (TGA)/Differential Scanning Calorimetry (DSC). The addition of Na2CO3, Na2SO4 and NaOH in the ore pretreatment increases nickel recovery from 14.80% without alkali roasting to 23.99%, 28.15% and 39.22%, respectively. The optimum extraction condition for nickel recovery is at pH 1 and a temperature of 80 °C. However, the highest Ni/Fe selectivity of 24,947 is obtained at pH 3 and a temperature of 80 °C, preceded by roasting in the absence of alkali. Compared to other hydrometallurgical processes, the process studied in this work exhibits lower recovery, but provides an alternative to extract nickel from low-grade limonite ore. Full article
(This article belongs to the Special Issue The Processing of Alternative and Urban Ores)
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11 pages, 41685 KB  
Article
Heading to Chaityabhoomi: Pilgrimages of Remembrance
by Anna Bochkovskaya
Religions 2018, 9(4), 111; https://doi.org/10.3390/rel9040111 - 4 Apr 2018
Viewed by 14227
Abstract
This article explores individual and collective pilgrimages to the Mumbai-based cremation ground (samādhi) of Bhimrao Ramji (Babasaheb) Ambedkar (1891–1956), a renowned economist and lawyer, academician and philosopher, political leader and social reformer who dedicated his life to the struggle for rights of [...] Read more.
This article explores individual and collective pilgrimages to the Mumbai-based cremation ground (samādhi) of Bhimrao Ramji (Babasaheb) Ambedkar (1891–1956), a renowned economist and lawyer, academician and philosopher, political leader and social reformer who dedicated his life to the struggle for rights of the untouchables (Dalits) in India. In October 1956, Dr. Ambedkar together with almost half a million of low-caste followers converted to Buddhism. After Babasaheb’s death on 6 December, 1956, his cremation ground became an object of worship for Buddhists and adherents of other religions. In December 1971, on the eve of the 15th year of his demise, the Chaityabhoomi memorial was inaugurated there. A dramatic increase in the number of pilgrims coming from all across India to Dr. Ambedkar’s samādhi as well as to other places associated with him has become instrumental in building up Dalits’ sites of memory/lieux de mémoire in contemporary India. The growing interest to Chaityabhoomi has also acquired a political dimension in contemporary India. Full article
(This article belongs to the Special Issue Sacred Journeys: Religious Tourism and Pilgrimage)
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