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12 pages, 468 KiB  
Article
Discrimination of Phytosterol and Tocopherol Profiles in Soybean Cultivars Using Independent Component Analysis
by Olivio Fernandes Galãoa, Patrícia Valderrama, Luana Caroline de Figueiredo, Oscar Oliveira Santos Júnior, Alessandro Franscisco Martins, Rafael Block Samulewski, André Luiz Tessaro, Elton Guntendorfer Bonafé and Jesui Vergilio Visentainer
AppliedChem 2025, 5(3), 19; https://doi.org/10.3390/appliedchem5030019 - 7 Aug 2025
Abstract
Soybean (Glycine max (L.) Merrill) is a major oilseed crop rich in phytosterols and tocopherols, compounds associated with functional and nutritional properties of vegetable oils. This study aimed to apply, for the first time, Independent Component Analysis (ICA) to discriminate the composition [...] Read more.
Soybean (Glycine max (L.) Merrill) is a major oilseed crop rich in phytosterols and tocopherols, compounds associated with functional and nutritional properties of vegetable oils. This study aimed to apply, for the first time, Independent Component Analysis (ICA) to discriminate the composition of phytosterols (β-sitosterol, campesterol, stigmasterol) and tocopherols (α, β, γ, δ) in 20 soybean genotypes—14 non-transgenic and six transgenic—cultivated in two major producing regions of Paraná state, Brazil (Londrina and Ponta Grossa). Lipophilic compounds were extracted from soybean seeds, quantified via gas chromatography and HPLC, and statistically analyzed using ICA with the JADE algorithm. The extracted independent components successfully differentiated soybean varieties based on phytochemical profiles. Notably, transgenic cultivars from Ponta Grossa exhibited higher levels of total tocopherols, including α- and β-tocopherol, while conventional cultivars from both regions showed elevated phytosterol content, particularly campesterol and stigmasterol. ICA proved to be a powerful unsupervised method for visualizing patterns in complex compositional data. These findings highlight the significant influence of genotype and growing region on the nutraceutical potential of soybean, and support the use of multivariate analysis as a strategic tool for cultivar selection aimed at enhancing functional quality in food applications. Full article
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18 pages, 3069 KiB  
Article
Transcriptomic Profiling of Buds Unveils Insights into Floral Initiation in Tea-Oil Tree (Camellia oleifera ‘changlin53’)
by Hongyan Guo, Zongshun Zhou, Jian Zhou, Chao Yan, Wenbin Zhong, Chang Li, Ying Jiang, Yaqi Yuan, Linqing Cao, Wenting Pan, Jinfeng Wang, Jia Wang, Tieding He, Yikai Hua, Yisi Liu, Lixian Cao and Chuansong Chen
Plants 2025, 14(15), 2348; https://doi.org/10.3390/plants14152348 - 30 Jul 2025
Viewed by 318
Abstract
Flowering is a key agronomic trait that directly influences the yield of the tea-oil tree (Camellia oleifera). Floral initiation, which precedes flower bud differentiation, represents a critical developmental stage affecting the flowering outcomes. However, the molecular mechanisms underlying floral initiation in [...] Read more.
Flowering is a key agronomic trait that directly influences the yield of the tea-oil tree (Camellia oleifera). Floral initiation, which precedes flower bud differentiation, represents a critical developmental stage affecting the flowering outcomes. However, the molecular mechanisms underlying floral initiation in C. oleifera remain poorly understood. In this study, buds from five key developmental stages of a 12-year-old C. oleifera cultivar ‘changlin53’ were collected as experimental samples. Scanning electron microscopy was employed to identify the stage of floral initiation. UPLC-MS/MS was used to analyze endogenous gibberellin (GA) concentrations, while transcriptomic analysis was performed to reveal the underlying transcriptional regulatory network. Six GA types were detected during floral initiation and petal development. GA4 was exclusively detected at the sprouting stage (BII), while GA3 was present in all samples but was significantly lower in BII and the flower bud primordium formation stage (BIII) than in the other samples. A total of 64 differentially expressed genes were concurrently enriched in flower development, reproductive shoot system development, and shoot system development. Weighted gene co-expression network analysis (WGCNA) identified eight specific modules significantly associated with different developmental stages. The magenta module, containing Unigene0084708 (CoFT) and Unigene0037067 (CoLEAFY), emerged as a key regulatory module driving floral initiation. Additionally, GA20OX1 and GA2OX8 were identified as candidate genes involved in GA-mediated regulation of floral initiation. Based on morphological and transcriptomic analyses, we conclude that floral initiation of C. oleifera is a continuous regulatory process governed by multiple genes, with the FT-LFY module playing a central role in the transition from apical meristem to floral meristem. Full article
(This article belongs to the Section Horticultural Science and Ornamental Plants)
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22 pages, 4619 KiB  
Article
Physiological and Transcriptomic Analyses Reveal Regulatory Mechanisms of Adventitious Root Formation in In Vitro Culture of Cinnamomum camphora
by Yuntong Zhang, Ting Zhang, Yongjie Zheng, Jun Wang, Chenglin Luo, Yuhua Li and Xinliang Liu
Int. J. Mol. Sci. 2025, 26(15), 7264; https://doi.org/10.3390/ijms26157264 - 27 Jul 2025
Viewed by 377
Abstract
Cinnamomum camphora is an ecologically and economically significant species, highly valued for its essential oil production and environmental benefits. Although a tissue culture system has been established for C. camphora, large-scale propagation remains limited due to the inconsistent formation of adventitious roots [...] Read more.
Cinnamomum camphora is an ecologically and economically significant species, highly valued for its essential oil production and environmental benefits. Although a tissue culture system has been established for C. camphora, large-scale propagation remains limited due to the inconsistent formation of adventitious roots (ARs). This study investigated AR formation from callus tissue, focusing on associated physiological changes and gene expression dynamics. During AR induction, contents of soluble sugars and proteins decreased, alongside reduced activities of antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD), and polyphenol oxidase (PPO). Levels of indole-3-acetic acid (IAA) and abscisic acid (ABA) decreased significantly throughout AR formation. Zeatin riboside (ZR) levels initially declined and then rose, whereas gibberellic acid (GA) levels displayed the opposite trend. Comparative transcriptomic and temporal expression analyses identified differentially expressed genes (DEGs), which were grouped into four distinct expression patterns. KEGG pathway enrichment indicated that 67 DEGs are involved in plant hormone signaling pathways and that 38 DEGs are involved in the starch and sucrose metabolism pathway. Additionally, protein–protein interaction network (PPI) analysis revealed ten key regulatory genes, which are mainly involved in auxin, cytokinin, GA, ABA, and ethylene signaling pathways. The reliability of the transcriptome data was further validated by quantitative real-time PCR. Overall, this study provides new insights into the physiological and molecular mechanisms underlying AR formation in C. camphora and offers valuable guidance for optimizing tissue culture systems. Full article
(This article belongs to the Special Issue Emerging Insights into Phytohormone Signaling in Plants)
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14 pages, 4097 KiB  
Article
Preparation and Performance Evaluation of Graphene Oxide-Based Self-Healing Gel for Lost Circulation Control
by Wenzhe Li, Pingya Luo and Xudong Wang
Polymers 2025, 17(15), 1999; https://doi.org/10.3390/polym17151999 - 22 Jul 2025
Viewed by 332
Abstract
Lost circulation is a major challenge in oil and gas drilling operations, severely restricting drilling efficiency and compromising operational safety. Conventional bridging and plugging materials rely on precise particle-to-fracture size matching, resulting in low success rates. Self-healing gels penetrate loss zones as discrete [...] Read more.
Lost circulation is a major challenge in oil and gas drilling operations, severely restricting drilling efficiency and compromising operational safety. Conventional bridging and plugging materials rely on precise particle-to-fracture size matching, resulting in low success rates. Self-healing gels penetrate loss zones as discrete particles that progressively swell, accumulate, and self-repair in integrated gel masses to effectively seal fracture networks. Self-healing gels effectively overcome the shortcomings of traditional bridging agents including poor adaptability to fractures, uncontrollable gel formation of conventional downhole crosslinking gels, and the low strength of conventional pre-crosslinked gels. This work employs stearyl methacrylate (SMA) as a hydrophobic monomer, acrylamide (AM) and acrylic acid (AA) as hydrophilic monomers, and graphene oxide (GO) as an inorganic dopant to develop a GO-based self-healing organic–inorganic hybrid plugging material (SG gel). The results demonstrate that the incorporation of GO significantly enhances the material’s mechanical and rheological properties, with the SG-1.5 gel exhibiting a rheological strength of 3750 Pa and a tensile fracture stress of 27.1 kPa. GO enhances the crosslinking density of the gel network through physical crosslinking interactions, thereby improving thermal stability and reducing the swelling ratio of the gel. Under conditions of 120 °C and 6 MPa, SG-1.5 gel demonstrated a fluid loss volume of only 34.6 mL in 60–80-mesh sand bed tests. This gel achieves self-healing within fractures through dynamic hydrophobic associations and GO-enabled physical crosslinking interactions, forming a compact plugging layer. It provides an efficient solution for lost circulation control in drilling fluids. Full article
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16 pages, 944 KiB  
Article
Artificial Intelligence in the Oil and Gas Industry: Applications, Challenges, and Future Directions
by Marcelo dos Santos Póvoas, Jéssica Freire Moreira, Severino Virgínio Martins Neto, Carlos Antonio da Silva Carvalho, Bruno Santos Cezario, André Luís Azevedo Guedes and Gilson Brito Alves Lima
Appl. Sci. 2025, 15(14), 7918; https://doi.org/10.3390/app15147918 - 16 Jul 2025
Viewed by 1200
Abstract
This study aims to provide a comprehensive overview of the application of artificial intelligence (AI) methods to solve real-world problems in the oil and gas sector. The methodology involved a two-step process for analyzing AI applications. In the first step, an initial exploration [...] Read more.
This study aims to provide a comprehensive overview of the application of artificial intelligence (AI) methods to solve real-world problems in the oil and gas sector. The methodology involved a two-step process for analyzing AI applications. In the first step, an initial exploration of scientific articles in the Scopus database was conducted using keywords related to AI and computational intelligence, resulting in a total of 11,296 articles. The bibliometric analysis conducted using VOS Viewer version 1.6.15 software revealed an average annual growth of approximately 15% in the number of publications related to AI in the sector between 2015 and 2024, indicating the growing importance of this technology. In the second step, the research focused on the OnePetro database, widely used by the oil industry, selecting articles with terms associated with production and drilling, such as “production system”, “hydrate formation”, “machine learning”, “real-time”, and “neural network”. The results highlight the transformative impact of AI on production operations, with key applications including optimizing operations through real-time data analysis, predictive maintenance to anticipate failures, advanced reservoir management through improved modeling, image and video analysis for continuous equipment monitoring, and enhanced safety through immediate risk detection. The bibliometric analysis identified a significant concentration of publications at Society of Petroleum Engineers (SPE) events, which accounted for approximately 40% of the selected articles. Overall, the integration of AI into production operations has driven significant improvements in efficiency and safety, and its continued evolution is expected to advance industry practices further and address emerging challenges. Full article
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16 pages, 3833 KiB  
Article
Seven Thousand Felt Earthquakes in Oklahoma and Kansas Can Be Confidently Traced Back to Oil and Gas Activities
by Iason Grigoratos, Alexandros Savvaidis and Stefan Wiemer
GeoHazards 2025, 6(3), 36; https://doi.org/10.3390/geohazards6030036 - 15 Jul 2025
Viewed by 273
Abstract
The seismicity levels in Oklahoma and southern Kansas have increased dramatically over the last 15 years. Past studies have identified the massive disposal of wastewater co-produced during oil and gas extraction as the driving force behind some earthquake clusters, with a small number [...] Read more.
The seismicity levels in Oklahoma and southern Kansas have increased dramatically over the last 15 years. Past studies have identified the massive disposal of wastewater co-produced during oil and gas extraction as the driving force behind some earthquake clusters, with a small number of events directly linked to hydraulic fracturing (HF) stimulations. The present investigation is the first one to examine the role both of these activities played throughout the two states, under the same framework. Our findings confirm that wastewater disposal is the main causal factor, while also identifying several previously undocumented clusters of seismicity that were triggered by HF. We were able to identify areas where both causal factors spatially coincide, even though they act at distinct depth intervals. Overall, oil and gas operations are probabilistically linked at high confidence levels with more than 7000 felt earthquakes (M ≥ 2.5), including 46 events with M ≥ 4.0 and 4 events with M ≥ 5. Our analysis utilized newly compiled regional earthquake catalogs and established physics-based principles. It first hindcasts the seismicity rates after 2012 on a spatial grid using either real or randomized HF and wastewater data as the input, and then compares them against the null hypothesis of purely tectonic loading. In the end, each block is assigned a p-value, reflecting the statistical confidence in its causal association with either HF stimulations or wastewater disposal. Full article
(This article belongs to the Special Issue Seismological Research and Seismic Hazard & Risk Assessments)
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21 pages, 6897 KiB  
Article
Performance Analysis of HVDC Operational Control Strategies for Supplying Offshore Oil Platforms
by Alex Reis, José Carlos Oliveira, Carlos Alberto Villegas Guerrero, Johnny Orozco Nivelo, Lúcio José da Motta, Marcos Rogério de Paula Júnior, José Maria de Carvalho Filho, Vinicius Zimmermann Silva, Carlos Andre Carreiro Cavaliere and José Mauro Teixeira Marinho
Energies 2025, 18(14), 3733; https://doi.org/10.3390/en18143733 - 15 Jul 2025
Viewed by 220
Abstract
Driven by the environmental benefits associated with reduced greenhouse gas emissions, oil companies have intensified research efforts into reassessing the strategies used to meet the electrical demands of offshore production platforms. Among the various alternatives available, the deployment of onshore–offshore interconnections via High-Voltage [...] Read more.
Driven by the environmental benefits associated with reduced greenhouse gas emissions, oil companies have intensified research efforts into reassessing the strategies used to meet the electrical demands of offshore production platforms. Among the various alternatives available, the deployment of onshore–offshore interconnections via High-Voltage Direct Current (HVDC) transmission systems has emerged as a promising solution, offering both economic and operational advantages. In addition to reliably meeting the electrical demand of offshore facilities, this approach enables enhanced operational flexibility due to the advanced control and regulation capabilities inherent to HVDC converter stations. Based on the use of interconnection through an HVDC link, aiming to evaluate the operation of the electrical system as a whole, this study focuses on evaluating dynamic events using the PSCAD software version 5.0.2 to analyze the direct online starting of a large induction motor and the sudden loss of a local synchronous generating unit. The simulation results are then analyzed to assess the effectiveness of both Grid-Following (GFL) and Grid-Forming (GFM) control strategies for the converters, while the synchronous generators are evaluated under both voltage regulation and constant power factor control operation, with a particular focus on system stability and restoration of normal operating conditions in the sequence of events. Full article
(This article belongs to the Special Issue Advanced Electric Power Systems, 2nd Edition)
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27 pages, 53601 KiB  
Article
Depositional Evolution and Controlling Factors of the Lower–Middle Jurassic in the Kuqa Depression, Tarim Basin, Northwest China
by Ming Ma, Changsong Lin, Yongfu Liu, Hao Li, Wenfang Yuan, Jingyan Liu, Chaoqun Shi, Manli Zhang and Fan Xu
Appl. Sci. 2025, 15(14), 7783; https://doi.org/10.3390/app15147783 - 11 Jul 2025
Viewed by 279
Abstract
The Lower–Middle Jurassic of the Kuqa Depression consists of terrestrial clastic deposits containing coal seams and thick lacustrine mudstones, and is of great significance for oil and gas exploration. Based on the comprehensive analysis of core, well-logging, outcrop, and seismic data, the sequence [...] Read more.
The Lower–Middle Jurassic of the Kuqa Depression consists of terrestrial clastic deposits containing coal seams and thick lacustrine mudstones, and is of great significance for oil and gas exploration. Based on the comprehensive analysis of core, well-logging, outcrop, and seismic data, the sequence stratigraphy, depositional systems, and the controlling factors of the basin filling in the depression are systematically documented. Four primary depositional systems, including braided river delta, meandering river delta, lacustrine, and swamp deposits, are identified within the Ahe, Yangxia, and Kezilenuer Formations of the Lower–Middle Jurassic. The basin fills can be classified into two second-order and nine third-order sequences (SQ1–SQ9) confined by regional or local unconformities and their correlative conformities. This study shows that the sedimentary evolution has undergone the following three stages: Stage I (SQ1–SQ2) primarily developed braided river, braided river delta, and shallow lacustrine deposits; Stage II (SQ3–SQ5) primarily developed meandering river, meandering river delta, and extensive deep and semi-deep lacustrine deposits; Stage III (SQ6–SQ9) primarily developed swamp (SQ6–SQ7), meandering river delta, and shore–shallow lacustrine deposits (SQ8–SQ9). The uplift of the Tianshan Orogenic Belt in the Early Jurassic (Stage I) may have facilitated the development of braided fluvial–deltaic deposits. The subsequential expansion of the sedimentary area and the weakened sediment supply can be attributed to the planation of the source area and widespread basin subsidence, with the transition of the depositional environments from braided river delta deposits to meandering river delta and swamp deposits. The regional expansion or rise of the lake during Stage II was likely triggered by the hot and humid climate conditions, possibly associated with the Early Jurassic Toarcian Oceanic Anoxic Event. The thick swamp deposits formed during Stage III may be controlled by the interplay of rational accommodation, warm and humid climatic conditions, and limited sediment supply. Milankovitch cycles identified in Stage III further reveal that coal accumulation was primarily modulated by long-period eccentricity forcing. Full article
(This article belongs to the Section Earth Sciences)
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32 pages, 2059 KiB  
Review
A State-of-the-Art Review on the Potential of Waste Cooking Oil as a Sustainable Insulating Liquid for Green Transformers
by Samson Okikiola Oparanti, Esther Ogwa Obebe, Issouf Fofana and Reza Jafari
Appl. Sci. 2025, 15(14), 7631; https://doi.org/10.3390/app15147631 - 8 Jul 2025
Viewed by 496
Abstract
Petroleum-based insulating liquids have traditionally been used in the electrical industry for cooling and insulation. However, their environmental drawbacks, such as non-biodegradability and ecological risks, have led to increasing regulatory restrictions. As a sustainable alternative, vegetable-based insulating liquids have gained attention due to [...] Read more.
Petroleum-based insulating liquids have traditionally been used in the electrical industry for cooling and insulation. However, their environmental drawbacks, such as non-biodegradability and ecological risks, have led to increasing regulatory restrictions. As a sustainable alternative, vegetable-based insulating liquids have gained attention due to their biodegradability, non-toxicity to aquatic and terrestrial ecosystems, and lower carbon emissions. Adopting vegetable-based insulating liquids also aligns with United Nations Sustainable Development Goals (SDGs) 7 and 13, which focus on cleaner energy sources and reducing carbon emissions. Despite these benefits, most commercially available vegetable-based insulating liquids are derived from edible seed oils, raising concerns about food security and the environmental footprint of large-scale agricultural production, which contributes to greenhouse gas emissions. In recent years, waste cooking oils (WCOs) have emerged as a promising resource for industrial applications through waste-to-value conversion processes. However, their potential as transformer insulating liquids remains largely unexplored due to limited research and available data. This review explores the feasibility of utilizing waste cooking oils as green transformer insulating liquids. It examines the conversion and purification processes required to enhance their suitability for insulation applications, evaluates their dielectric and thermal performance, and assesses their potential implementation in transformers based on existing literature. The objective is to provide a comprehensive assessment of waste cooking oil as an alternative insulating liquid, highlight key challenges associated with its adoption, and outline future research directions to optimize its properties for high-voltage transformer applications. Full article
(This article belongs to the Special Issue Novel Advances in High Voltage Insulation)
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7 pages, 1300 KiB  
Data Descriptor
Global Database for Naturally Occurring Radionuclides Associated with Offshore Oil and Gas Production
by Ziran Wei, Songjie He, Stephanie Sharuga and Kanchan Maiti
Data 2025, 10(7), 107; https://doi.org/10.3390/data10070107 - 1 Jul 2025
Viewed by 396
Abstract
This study compiles a comprehensive dataset on the occurrence, distribution, and potential impacts of Naturally Occurring Radionuclides (NORMs) near offshore oil and gas platforms. It encompasses data, including activities (Bq/l) and exposure levels (Msv), derived from various environmental matrices. A particular emphasis is [...] Read more.
This study compiles a comprehensive dataset on the occurrence, distribution, and potential impacts of Naturally Occurring Radionuclides (NORMs) near offshore oil and gas platforms. It encompasses data, including activities (Bq/l) and exposure levels (Msv), derived from various environmental matrices. A particular emphasis is placed on petroleum products and waste, such as produced water, scales, and sludges. The dataset contributes to a better understanding of the distribution of NORM wastes in marine environments, informs future radiological safety standards, contributes to the formulation of regulatory policies, and facilitates the design of mitigation strategies. The information—literature and data from five continents over the past 70 years—has been carefully compiled and organized to support intuitive analysis, making it a valuable tool for policymakers and researchers. Full article
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14 pages, 5669 KiB  
Article
Preventive Effects of Medium-Chain Fatty Acid Intake on Muscle Atrophy
by Madoka Sumi, Takuro Okamura, Tomoyuki Matsuyama, Tomoki Miyoshi, Hanako Nakajima, Naoko Nakanishi, Ryoichi Sasano, Masahide Hamaguchi and Michiaki Fukui
Nutrients 2025, 17(13), 2154; https://doi.org/10.3390/nu17132154 - 28 Jun 2025
Viewed by 907
Abstract
Background/Objectives: Medium-chain fatty acids (MCFAs), abundant in coconut oil, have attracted considerable attention in recent years owing to their potential impact on muscle atrophy. However, the mechanisms underlying their effects remain inadequately understood. This study aimed to examine the impact of coconut-oil-derived [...] Read more.
Background/Objectives: Medium-chain fatty acids (MCFAs), abundant in coconut oil, have attracted considerable attention in recent years owing to their potential impact on muscle atrophy. However, the mechanisms underlying their effects remain inadequately understood. This study aimed to examine the impact of coconut-oil-derived MCFAs on skeletal muscle in a mouse model administered a high-fat diet. Methods: C57BL/6J mice were assigned to a normal diet, lard diet, or coconut oil diet and maintained for a duration of 12 weeks. A glucose tolerance test was conducted, and biochemical parameters, muscle histological analysis, and gene expression in muscle tissue were assessed. MCFA concentrations in serum and muscle were quantified utilizing gas chromatography–mass spectrometry. An in vitro experiment was conducted by treating mouse C2C12 myotube cells with lauric acid and palmitic acid, followed by a gene expression evaluation. Results: Mice fed a coconut-oil-based diet exhibited reduced body weight gain and lower blood glucose and total cholesterol levels compared to those fed a lard-based diet. The coconut-oil-fed group showed increased concentrations of MCFAs in both serum and muscle tissue, along with an improvement in relative grip strength. The expression levels of proteins and genes associated with muscle atrophy were reduced in muscle tissue. These findings were corroborated in vitro using C2C12 myotube cells. Conclusions: Coconut oil may preserve muscle strength by increasing MCFA concentrations in serum and muscle tissue, while suppressing the expression of muscle-atrophy-related proteins and genes. These findings suggest that coconut oil may be beneficial in preventing muscle atrophy induced by long-chain fatty acids. Full article
(This article belongs to the Section Lipids)
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13 pages, 214 KiB  
Article
Energy Implications and Environmental Analysis of Oil Rigs Decommissioning Options Using LCA Methodology
by Barbara Marchetti, Francesco Corvaro and Marta Rossi
Energies 2025, 18(13), 3372; https://doi.org/10.3390/en18133372 - 26 Jun 2025
Viewed by 330
Abstract
The decommissioning of offshore oil rigs presents complex environmental challenges and opportunities, particularly in the context of energy transition goals and marine ecosystem protection. This study applies a Life Cycle Assessment (LCA) approach to evaluate the energy and environmental impacts associated with two [...] Read more.
The decommissioning of offshore oil rigs presents complex environmental challenges and opportunities, particularly in the context of energy transition goals and marine ecosystem protection. This study applies a Life Cycle Assessment (LCA) approach to evaluate the energy and environmental impacts associated with two different decommissioning approaches: full removal and partial removal. The analysis considers greenhouse gas emissions, energy consumption, material recovery, and long-term waste management. The study demonstrates important energy savings through the recovery and recycling of steel, which offsets energy-intensive operations such as cutting and marine transport. In addition, the analysis underscores the potential of integrating decommissioned infrastructure into offshore renewable energy systems, highlighting synergies with circular economy principles and the decarbonization of offshore operations. The findings highlight the importance of site-specific assessments and integrated policy frameworks to guide environmentally sound decommissioning decisions in offshore energy infrastructure. The analysis shows that full removal results in 14,300 kg CO2 eq emissions during cutting and transport, compared to 3090 kg CO2 eq for partial removal. Meanwhile, steel recycling generates environmental benefits of −3.80 × 106 kg CO2 eq for full removal and −1.17 × 106 kg CO2 eq for partial removal. Full article
25 pages, 12391 KiB  
Article
Pore Pressure Prediction and Fluid Contact Determination: A Case Study of the Cretaceous Sediments in the Bredasdorp Basin, South Africa
by Phethile Promise Shabangu, Moses Magoba and Mimonitu Opuwari
Appl. Sci. 2025, 15(13), 7154; https://doi.org/10.3390/app15137154 - 25 Jun 2025
Viewed by 427
Abstract
Pore pressure prediction gives drillers an early warning of potential oil and gas kicks, enabling them to adjust mud weight pre-emptively. A kick causes a delay in drilling practices, blowouts, and jeopardization of the wells. Changes in pore pressure affect the type of [...] Read more.
Pore pressure prediction gives drillers an early warning of potential oil and gas kicks, enabling them to adjust mud weight pre-emptively. A kick causes a delay in drilling practices, blowouts, and jeopardization of the wells. Changes in pore pressure affect the type of fluid contact in the reservoir. This study predicted the pore pressure and determined fluid contacts within the Lower Cretaceous and early Upper Cretaceous (Barremian to early Cenomanian) sandstone reservoirs of the Bredasdorp Basin using well logs and repeat formation test (RFT) data from three wells: E-BK1, E-AJ1, and E-CB1. Eaton’s method of developing a depth-dependent Normal Compact Trend (NCT), using resistivity and sonic wireline logs, as well as other methods including the Mathews and Kelly, Baker and Wood, and Modified Eaton and Bowers methods, were employed for pore pressure prediction. Eaton’s method provided reliable pore pressure results in all the wells when compared to alternative methods in this study. Overburden gradient and predicted pore pressures ranged from 1.84 gm/cc to 2.07 gm/cc and from 3563.74 psi to 4310.06 psi, respectively. Eaton’s resistivity and density/neutron log method results indicated normal pressure in E-BK1 and E-AJ1, as well as overpressured zones in E-AJ1. However, in E-CB1, the results showed only overpressured zones. The E-AJ1 significant overpressures were from 2685 m to 2716 m and from 2716 m to 2735 m in the pores exceeding 7991.54 psi. Gas–water contact (GOC) was encountered at 2967.5 m in E-BK1, while oil–gas contact (OGC) was at 2523 m in E-CB1, and gas–oil and oil–water contacts (GOC and OWC) were at 2699 m and 2723 m, respectively, in E-AJ1. In E-CB1, oil–water contact (OWC) was at 2528.5 m. Fluid contacts observed from the well logs and RFT data were in close agreement in E-AJ1, whereas there was no agreement in E-CB1 because the well log observations showed a shallower depth compared to RFT data with a difference of 5.5 m. This study illustrated the significance of an integrated approach to predicting fluid contacts and pore pressure within the reservoirs by showing that fluid contacts associated with overpressures were gas–water and oil–water contacts. In contrast, gas–oil contact was associated with normal pressure and under pressure. Full article
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22 pages, 3588 KiB  
Article
Trace Metal and Metalloid Profiles in Hair Samples from Children in the Oil-Producing Region of Kazakhstan
by Gulnara Batyrova, Victoria Kononets, Gulmira Umarova, Gulaim Taskozhina, Yeskendir Umarov, Zhamilya Issanguzhina, Khatimya Kudabayeva and Rabbil Batyrov
Toxics 2025, 13(7), 522; https://doi.org/10.3390/toxics13070522 - 21 Jun 2025
Viewed by 502
Abstract
Toxic elements are considered a significant threat to public health in oil-producing countries. Western Kazakhstan is experiencing serious environmental problems due to the development of the oil and gas industry. This study aimed to assess the concentrations of toxic trace elements—aluminum (Al), arsenic [...] Read more.
Toxic elements are considered a significant threat to public health in oil-producing countries. Western Kazakhstan is experiencing serious environmental problems due to the development of the oil and gas industry. This study aimed to assess the concentrations of toxic trace elements—aluminum (Al), arsenic (As), beryllium (Be), cadmium (Cd), mercury (Hg), and lead (Pb)—in the hair of children residing in Kazakhstan’s oil and gas-producing region, and to evaluate the relationship between the concentration of toxic elements and the remoteness of their residence from oil and gas fields. A cross-sectional analysis was conducted involving 1595 school-aged children. Element levels in hair samples were quantified using inductively coupled plasma mass spectrometry (ICP-MS). The association between trace element concentrations and residential distance from oil and gas fields was examined across three distance-based groups and further analyzed through multiple linear regression. The highest concentration of Al = 4.824 μg/g and Hg = 0.096 μg/g was found in the hair of children living close to oil and gas fields (0–16 km). A decrease in levels of Al (−0.072 (CI: −0.109; −0.036)) and Hg (−0.293 (CI: −0.343; −0.243)) is associated with increasing distance from oil and gas fields. As, Cd, and Pb had the lowest median concentrations in the hair of children living near oil and gas fields (0.030, 0.010, and 0.122 µg/g, respectively). There is a tendency for levels of As, Cd, and Pb to increase with distance from the fields (0.064 (CI: 0.039; 0.089), 0.093 (CI: 0.045; 0.141), and 0.244 (CI: 0.202; 0.287), respectively). Our findings indicate the need for biomonitoring of toxic elements to determine long-term temporal trends in the influence of toxic trace elements on the health of the child population of Western Kazakhstan. Full article
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16 pages, 756 KiB  
Article
New Insight into the Microstructure Changes and Molecular Mobility of Polyamides Exposed to H2S Scavengers
by Marina Perassoli de Lazari, Antonio Henrique Monteiro da Fonseca Thomé da Silva, Rodrigo Henrique dos Santos Garcia, Sylvia Correa dos Santos Teixeira, João Eduardo de Oliveira, Érica Gervasoni Chaves, Luiz Antônio de Oliveira Nunes, Hercílio de Angeli Honorato, Sonia Maria Cabral de Menezes, Aline Pinde Lima, Luiz Silvino Chinelatto Junior and Eduardo Ribeiro de Azevedo
Polymers 2025, 17(12), 1634; https://doi.org/10.3390/polym17121634 - 12 Jun 2025
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Abstract
Polyamides (PAs) are widely used as barrier materials in offshore oil and gas (O&G) equipment due to their mechanical strength and chemical resistance. However, long-term exposure to hydrogen sulfide scavengers (H2S-SCVs) may significantly affect their physicochemical properties. Previous studies using thermal [...] Read more.
Polyamides (PAs) are widely used as barrier materials in offshore oil and gas (O&G) equipment due to their mechanical strength and chemical resistance. However, long-term exposure to hydrogen sulfide scavengers (H2S-SCVs) may significantly affect their physicochemical properties. Previous studies using thermal analysis and 1H time-domain NMR (1H TD-NMR) suggest that ethoxylated H2S-SCVs impose molecular constraints, increasing the glass transition temperature (Tg) and reducing chain mobility above Tg. The present study builds upon these findings using a multi-technique analytical approach, including FTIR, Raman, 1H DQ-TD-NMR, and 13C solid-state NMR (ssNMR), to provide a more comprehensive understanding of the molecular alterations in PA materials. The results clearly demonstrate that H2S-SCV exposure leads to the progressive exudation of plasticizers from the PA matrix. This plasticizer loss is a key factor contributing to the observed shift in Tg and the reduction in molecular mobility. 1H DQ-TD-NMR data confirmed an increase in the density of dynamically constrained chains over time and allowed for the characterization of heterogeneity in these constraints throughout the PA matrix. Moreover, 13C ssNMR spectra revealed the presence of immobilized H2S-SCV chemical groups within the polymer matrix, strongly supporting the early statement that the mobility constraints observed in 1H DQ-TD-NMR are associated with the formation of crosslinks induced by the H2S-SCV: H2S-SCV acts as a crosslinking agent. Taken together, our findings indicate that both plasticizer loss and H2S-SCV-induced crosslinking contribute significantly to the microstructural evolution of PAs when exposed to ethoxylated H2S-SCVs, offering important insights into their degradation mechanisms and long-term behavior in aggressive operational environments. Full article
(This article belongs to the Special Issue Advanced Spectroscopy for Polymers: Design and Characterization)
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