Unconventional Sources Research Articles

Will we use Micro Black Holes to Power Spacetime Warping for Creating Micro Wormholes?

In the realm of theoretical physics, the concept of harnessing micro black holes for spacetime warping and the creation of micro wormholes presents a highly ambitious and intriguing idea. The proposition, originating from Zhan-Feng Mai and Run-Qiu Yang of Tianjin University in China, revolves around the utilization of ultra-dense primordial black holes as unconventional energy sources. These black holes, possibly as small as subatomic particles, could provide energy not from their intrinsic properties but through the gravitational forces at their event horizons.

Evaluation of coal mine drainage and associated precipitates for radium and rare earth element concentrations

Coal mine drainage (CMD) and associated metal-rich precipitates have recently been proposed as unconventional sources of rare earth elements (REEs). However, the potential occurrence of radium (Ra), a known carcinogen, with the REE-bearing phases has not been investigated. We hypothesized that Ra may occur in solids that are precipitated from CMD as a “radiobarite” solid solution ((Ba,Sr,Ra)SO4) and/or adsorbed with hydrous metal oxides. REEs have been documented to sorb or co-precipitate with iron (Fe), manganese (Mn), and aluminum (Al) oxyhydroxide in CMD solids. Likewise, Ra has been documented to sorb to hydrous Fe and Mn oxides especially where sulfate (SO4) and/or barium (Ba) concentrations are insufficient to precipitate radiobarite. Thus, we conducted the first-ever survey of Ra concentrations in corresponding CMD water and solid samples in the United States. Samples were analyzed from 4 untreated and 9 treated CMD sites in both the bituminous and anthracite coal regions of Pennsylvania across a range of pH and SO4 concentrations. The dissolved Ra in CMD was relatively low (<0.5 Bq/L), consistent with radiobarite solubility; however, CMD solids were largely composed of amorphous Fe, Al, and Mn oxyhydroxide and silicate minerals. Ra was associated with Mn-enriched CMD solids, upwards of 875 Bq/kg. Total REE + yttrium (Y) content in the CMD solids was enriched upwards of 3600 mg/kg and was significantly correlated with Al content. These preliminary results suggest that REE extraction may target Al-rich solids to avoid Ra in Mn-rich solids.

Comparative analysis of reverse osmosis and nanofiltration for the removal of dissolved contaminants in water reuse applications

The increasing demand for drinking water has led to the adoption of unconventional water sources, such as water reuse. Reverse osmosis (RO) and nanofiltration (NF) membranes are effective barriers against trace organic contaminants in potable water reuse applications. However, the use of RO is being challenged by NF, primarily due to NF's potential to achieve similar contaminant removal as RO but with higher productivity and lower energy requirements. This study compares NF and RO membranes in terms of contaminant removal and energy consumption for potable water reuse applications. RO (BW30XFR) and dense and loose NF (NF90 and NF270) membranes were tested in bench-scale systems, and RO (TW30) and NF (NF9) membrane elements were tested in an engineering scale system utilizing UF-filtered reclaimed wastewater. The highest solute passage was observed using NF270 membrane. There was no difference between NF90 and BW30XFR in terms of divalent ion passage, but NF90's total organic carbon and monovalent ion passages were higher. Both NF90 and BW30XFR highly rejected negatively charged trace organic contaminants (TOrCs), though rejections were lower for neutral and positively charged compounds. Furthermore, all compounds were highly rejected in the engineering-scale system by NF9 and TW30. These results highlight the potential of dense NF membranes as an energy-efficient barrier for contaminant removal.

Solar-Driven Drum-Type Atmospheric Water Harvester Based on Bio-Based Gels with Fast Adsorption/Desorption Kinetics.

Sorption-based atmospheric water harvesting is an attractive technology for exploiting unconventional water sources. A critical challenge is how to facilitate fast and continuous collection of potable water from air. Here, a bio-based gel (cellulose/alginate/lignin gel, CAL gel), resulting from the integration of a whole biomass-derived polymer network with lithium chloride is reported. A fast adsorption/desorption kinetics, with a water capture rate of 1.74kg kg-1 h-1 at 30% relative humidity and a desorption rate of 1.98kg kg-1 h-1, is simultaneously realized in one piece of CAL gel, because of its strong hygroscopicity, hydrophilic network, abundant water transport channels, photothermal conversion ability, and ≈200-µm-thick self-supporting bulky structure caused by multicomponent synergy. A solar-driven, drum-type, tunable, and portable harvester is designed that can harvest atmospheric water within a brief time. Under outdoor conditions, the harvester with CAL gels operates 36 switches (180°) per day realizes a water yield of 8.96kg kggel -1 (18.87g kgdevice -1). This portable harvester highlights the potential for fast and scalable atmospheric water harvesting in extreme environments.

Determine Oil and Water Saturations in Preserved Source Rocks From 2D T1-T2 NMR

Two-dimensional (2D) T1-T2 NMR has been widely proposed as a method to determine the fluids present in unconventional source rocks. However, the assignment of the components in the 2D T1- T2 NMR spectra has so far been based on conceptual consideration and lacks rigorous experimental verification. Many assignment variations appeared in the literature and can be misleading. For example, large T1/T2 peaks in the 2D T1-T2 NMR were suggested to be fluid in small pores coupled with kerogen solid through dipolar relaxation. Our recent 500-MHz NMR relaxation experiments found that the dipolar relaxation between nanoconfined fluids and solid matrix is not big enough to support that large T1/T2 interpretation. The objective of this paper is to determine what quantitative data can be obtained using 2D T1-T2 NMR from source rocks with high confidence. We found the oil and water saturation can be accurately measured in preserved source rock plugs. Two-dimensional T1-T2 NMR data were collected on preserved core plugs from five wells of a source rock reservoir using an inversion-recovery Carr-Purcell-Meiboom-Gill (CMPG) pulse sequence on a 12-MHz NMR instrument. The acquired 2D data were inverted using an optimized inversion software, MUPen2D. We then obtain oil and water content in the plug from the 2D T1-T2 NMR using an in-house-developed NMR MATLAB app. The porosity of all the plugs was measured using a combined NMR and gas porosimetry (CNG) method. Oil and water saturation were also obtained using an industry-standard method developed by the Gas Research Institute (GRI) on the rock material close to where the plug was drilled. The oil and water saturations measured on the preserved plugs using 2D T1-T2 NMR and CNG are consistent with those from the GRI method using crushed rocks and an invasive cleaning procedure. The results show that oil and water saturations were accurately determined from 2D T1-T2 NMR on preserved source rock samples with high confidence. The NMR method is nondestructive and noninvasive and takes less than 4 hours on a preserved source rock plug, while GRI is destructive and invasive and can take several weeks for an accurate measurement on one sample. The measured results can be further used to determine the production potential of a source rock well in combination with log data.

Screening the optimal Cox/CeO2(110) (x = 1–6) catalyst for methane activation in coalbed gas

The challenges posed by energy and environmental issues have forced mankind to explore and utilize unconventional energy sources. It is imperative to convert the abundant coalbed gas (CBG) into high value-added products, i.e., selective and efficient conversion of methane from CBG. Methane activation, known as the “holy grail”, poses a challenge to the design and development of catalysts. The structural complexity of the active metal on the carrier is of particular concern. In this work, we have studied the nucleation growth of small Co clusters (up to Co6) on the surface of CeO2(110) using density functional theory, from which a stable loaded Co/CeO2(110) structure was selected to investigate the methane activation mechanism. Despite the relatively small size of the selected Co clusters, the obtained Cox/CeO2(110) exhibits interesting properties. The optimized Co5/CeO2(110) structure was selected as the optimal structure to study the activation mechanism of methane due to its competitive electronic structure, adsorption energy and binding energy. The energy barriers for the stepwise dissociation of methane to form CH3*, CH2*, CH*, and C* radical fragments are 0.44, 0.55, 0.31, and 1.20 eV, respectively, indicating that CH* dissociative dehydrogenation is the rate-determining step for the system under investigation here. This fundamental study of metal-support interactions based on Co growth on the CeO2(110) surface contributes to the understanding of the essence of Co/CeO2 catalysts with promising catalytic behavior. It provides theoretical guidance for better designing the optimal Co/CeO2 catalyst for tailored catalytic reactions.

A nonwoven supported mixed matrix membrane for CH4/N2 separation

Efficiently enriching low-concentration CH4 is pivotal for enhancing the utilization of unconventional energy sources and mitigating greenhouse gas emissions. This study focuses on modifying the overall performance of CH4/N2 separation membranes. A novel mixed matrix membrane (MMM) with a reinforced substrate structure was developed through a straightforward dip-coating technique. This MMM incorporates a polytetrafluoroethylene (PTFE) porous membrane as the supporting framework, while a composite of block polymer (styrene-butadiene-styrene) and metal–organic framework (Ni-MOF-74) forms the selective separation layer. Comprehensive characterization of Ni-MOF-74 and the fabricated membranes was conducted using X-rays diffraction, scanning electron microscope, Brunauer–Emmett–Teller analysis, and gas permeance tests. The findings indicate a robust integration of the PTFE porous support with the membrane layer, enhancing the mechanical stability of the MMM. Under optimal conditions, the mechanical strength of the PM20 membrane (containing 20% Ni-MOF-74) was observed to be 37.7 MPa, representing remarkable increase compared to the non-reinforced MMM. Additionally, the PM20 membrane exhibited an impressive CH4 permeation rate of 92 Barrer (1 Barrer = 3.35×10–16 mol·m·m–2·s–1·Pa–1) alongside a CH4/N2 selectivity of 4.18. These results underscore the MMM's substantial performance and its promising potential in methane enrichment applications.

‘One System, Two Shadows’: A local public finance perspective on China's shadow banking system

Why does shadow banking persist in China despite repeated policy efforts to contain it? While studies of informal finance have traditionally emphasized the credit needs of private businesses as a demand-side explanation, this study contends that China's local public finance also constitutes an important driver for shadow banking. Based on document research and administrative data, we find that China's shadow banking system has bifurcated into two segments since the Global Financial Crisis (GFC). One is the ‘entrepreneurial shadow’ that has long provided informal credit to the private sector, especially small- and medium-sized enterprises. The other is a ‘fiscal shadow’, which serves property developers and local government financing vehicles (LGFVs), the two pillars of China's land-based local public finance regime. Property developers are major contributors to local fiscal revenues through the land economy, while LGFVs function as off-balance sheet backdoor financing intermediaries for local governments.Although localities have borrowed from unconventional sources throughout the reform era, the central government's GFC stimulus plan marked a turning point by fueling a debt-financed real estate and infrastructure construction boom. Property developers and LGFVs were launched onto a highly leveraged model of feverish expansion for over a decade. When the central government abruptly reversed its course by restricting the availability of formal credit, they became further entangled into the fiscal shadow for refinancing. Local public finance has thus become reliant on shadow banking, despite subsequent policy efforts to curb such activity. Our findings suggest the need for a more integrated analytic and regulatory framework that recognizes the mutual dependence between shadow banking and local debt – two major sources of systemic financial risks in China.

Oxidative Hydraulic Fracturing Fluid to Enhance Production from Source Rock Reservoirs

Summary The steep production declines generally observed after hydraulic fracturing in unconventional source rock reservoirs has been attributed to several potential causes. Recently, a new additive to the stimulation fluid system was proposed to extend economical longer-term production from these formations. Oxidizer-laden fracturing fluid systems are shown to create cracks and deep channels within the organic matter present in the source rock, such as kerogen, thereby increasing the source rock permeability and enhancing the hydraulic conductivity of the exposed fracture faces. To this end, the fluid design and recommendations for its application are illustrated herein. Oxidants composed of oxychlorine (ClOn−) and oxybromine (BrOn–) (where n = 0 to 4) are effective for kerogen depolymerization or degradation at depth. This study illustrates the beneficial effects of two specific oxidizers—sodium chlorite (NaClO2) and sodium bromate (NaBrO3)—on kerogen-rich source rock subjected to in-situ reservoir conditions. Source rock samples were cut and polished to test the oxidizer’s impact on the organic and inorganic regions. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) were performed on the rock surface to identify specific organic matter features. The samples were then chemically treated with varying conditions of NaClO2 or NaBrO3 (concentration range: 0.013–0.054 M; temperature: 150°C; and time: 3–24 hours). Samples were returned to the scanning electron microscope for post-treatment analysis. Furthermore, the oxidants were packaged within a slickwater hydraulic fracturing fluid system for field application, and their effects on viscosity and friction reduction were also studied. SEM images and EDS maps of kerogen-rich rock samples observed before and after treatment with oxidizing fluid showed a series of cracks formed throughout the organic matter domains, where increasing the concentration of oxidizer in the treatment fluid showed a clear increase in the prevalence of cracks throughout the surface. The effect of time was also observed, as short treatment times resulted in porosity/permeability creation in the kerogen, though longer treatment times were associated with more severe degradation. Optimal conditions for NaClO2 and NaBrO3 concentrations in the additive fluid systems were different and will be herein highlighted. Each oxidizer (10–20 pptg concentration) was added to slickwater with variable friction reducer concentration (1 gpt, 2 gpt, and 4 gpt), and shear sweeps performed at both 70°F and 180°F. A negligible difference is observed between the viscosities of the base fluid and the fluid with either oxidant at low friction reducer concentration. Meanwhile, flow loop tests demonstrated that the oxidizer did not affect the friction reducer except to slightly boost the performance due to the salt effect on the polymer. Two strong oxidants, available as commodity chemicals, are shown to be effective in cracking kerogen and any present organic matter, thus creating permeable channels and enhancing the overall permeability of the exposed source rock fracture faces. Meanwhile, the proposed fracturing fluid additives display good compatibility with other slickwater fluid components, demonstrating the potential for universal usage in unconventional stimulations. The recommendations for its application as a fluid additive in slickwater are herein illustrated.

Progressive substitution of fish oil with Schizochytrium-derived algal oil in the diet of Atlantic salmon (Salmo salar) parr subjected to winter signal period

The aim of this study was to investigate the impact of progressive replacement of fish oil with Schizochytrium-derived oil from Veramaris® (VMO) in the diets of Atlantic salmon, focusing on its effect during the pre-adaptation to smoltification phase of parr, with an emphasis on the winter signal period. Substitution of fish oil with VMO during this critical developmental phase of salmon (pre-adaptation to smoltification phase) can contribute to the goal of reducing dependence on wild fisheries as a primary source of essential fatty acids in aquafeeds. Three isoproteic, isolipidic and isoenergetic diets were formulated; a control diet containing 5% fish oil and 12% plant oil (0VMO) and two other diets, in which 50% and 100% of the EPA+DHA from fish oil were replaced with VMO, henceforth referred to as 50VMO and 100VMO, respectively. The fish were exposed to a 12 L:12D photoperiod over a 49-day window with samples collected at five time points, including a 48-h salt water challenge to evaluate the effects on common smoltification-related biomarkers including the expression of two genes coding for the two protein isoforms of the NKA alpha catalytic subunit (nkaa1a, nkaa1b), the gene coding for NA+/K+Cl⁻ co-transporter (nkcc1) in the gills as well as osmolality, Cl-, Mg2+, Ca2+, cortisol, growth hormone, and insulin-like growth factor-1 in plasma. The results showed non-significant differences in growth performance and only minor differences in smoltification-related parameters between the dietary treatment groups. Overall, the unconventional source of EPA+DHA was not detrimental to growth, hypoosmoregulatory ability or general welfare, suggesting that the progressive substitution of fish oil with Schizochytrium-derived oil in diets for Atlantic salmon parr is a viable option for adoption by the aquaculture industry.

PUMPKIN AND PASTEL WINE, A FRUIT AND A LEGUME OF THE CUCURBITACEES FAMILY IN GREEN CIRCULAR ECONOMY WITH ZERO WASTE

This study explores the viability of watermelon (Citrullus lanatus) and pumpkin (Cucurbita pepo subsp. Pepo) as unconventional sources for sustainable winemaking, contributing to a zero-waste circular economy in viticulture. The research employs a multidimensional methodology encompassing chemical analyses, sensory evaluations, and environmental impact assessments to scrutinize the entire lifecycle of wine production. The findings reveal watermelon wine's superiority, boasting a 14° alcohol content, while pumpkin wine ranges at 11°. Both wines maintain physico-chemical and organoleptic attributes, with minimal alterations in micronutrient content. The compost generated from processing waste contains essential nutrients for plant growth. Comparative analysis underscores the advantageous nature of this compost, laying the foundation for sustainable winemaking practices in Madagascar and illuminating the untapped potential of tropical fruits in the global viticultural landscape. This study, pioneering the valorization of unconventional fruit and vegetable in Madagascar, strives to contribute to the discourse on environmentally conscious winemaking, fostering a paradigm shift toward ecologically harmonious practices in the agro-industrial sector.

Innovative integrated workflow for data-driven production forecasting and well completion optimization: A Montney Formation case study

With the use of advanced data analytics and machine learning (ML) techniques, the oil and gas industry has transformed significantly in recent years. These innovations have opened new opportunities in reservoir engineering, allowing engineers to leverage data for better decision-making and well completion optimization. A key challenge in hydrocarbon exploration and production is forecasting gas production rates from unconventional sources. This is a crucial factor that affects how resources are allocated and decisions are made, requiring the application of novel techniques to enhance hydrocarbon production. Here, a novel and comprehensive automated workflow is introduced covering data collection, data preparation, feature selection, ML model development, and operational parameter optimization. The workflow uses various ML and optimization methods, including a modified Differential Evolution (MDE) algorithm, to improve gas production forecasting and optimize well completion parameters. We applied the proposed workflow to 3144 horizontal gas wells in the Montney Formation, British Columbia (BC), Canada, to assess its performance. The results showed the advantages of incorporating the initial 24 months of cumulative gas production data alongside well and completion data. Also, following the fine-tuning of hyperparameters for the ML algorithms, we identified the most effective model for forecasting cumulative gas production within the Montney Formation as a two-layer Artificial Neural Network (ANN) model. Moreover, using the MDE algorithm, the optimization results revealed the possibility of increasing gas production by more than 10% for about 47% of the wells. This research makes a significant contribution to the field of unconventional gas exploration by introducing an automated workflow that simplifies data processing, model development, and decision-making processes. It also offers valuable insights for optimizing unconventional gas production in the Montney Formation and similar reservoirs, as the energy industry moves towards more sustainable and efficient practices.

Navigating the water–energy nexus amidst the Lebanese economic crisis

ABSTRACT Lebanon's economic crisis has disrupted the country's energy and water sectors, highlighting their interdependence. The methodology involves surveying 150 municipalities across all Lebanese governorates, ensuring a comprehensive coverage of public and private water resources. Data on water and energy were collected before and during the crisis to explore this nexus during periods of economic turmoil. The findings reveal a decline in water provision during the crisis, with the average weekly water supply plummeting from 49 h in 2019 to 22 h in 2023. Concurrently, the use of water tankers has surged from 26 to 44%, indicating a concerning shift in water acquisition methods. Despite the crisis, conventional water sources remain predominant, while unconventional sources account for less than 1% of the total supply. In response to the energy shortage, renewable energy sources have gained traction in residential, commercial, and industrial sectors. The scarcity and rising cost of electricity have driven the adoption of solar photovoltaics in the water sector, reaching 4.8% for extraction from underground reservoirs and 2.8% for distribution. Similarly, the use of solar water heaters has increased from 7.9 to 15.4% in 2023. These findings underscore the interplay between energy and water security during periods of economic instability.

Improving the in-situ upgrading of extra heavy oil using metal-based oil-soluble catalysts through oxidation process for enhanced oil recovery

The demand for fuel from unconventional sources is increasing all over the world, however, there are still special and strict regulations regarding the methods of enhanced oil recovery as well as the content of the oil produced, including the amount of sulfur. In-situ combustion (ISC) is an attractive thermal method to enhance oil recovery and in-situ upgrading process. In this work, copper (II) oleate and copper (II) stearate were used for the oxidation of extra heavy oil with high sulfur content in the ISC process using a self-designed porous medium thermo-effect cell (PMTEC) and visual combustion tube. Using PMTEC the catalytic performances of the synthesized oil-soluble copper (II) oleate and copper (II) stearate and kinetic parameters such as activation energy using Ozawa-Flynn-Wall method were studied. The X-ray diffraction (XRD) and high-resolution field emission scanning electron microscopy were used to examine the characteristics of in-situ synthesized CuO nanoparticles during oxidation. As shown, the presence of oil-soluble copper (II) stearate and copper (II) oleate reduced oil viscosity from 9964 to 8000 and 6090 mPa˙s, respectively. Following ISC process in porous media in the presence of copper (II) oleate, the high sulfur extra heavy oil upgraded, and its sulfur content decreased from 10.33 to 6.79%. Additionally, SARA analysis revealed that asphaltene and resin content decreased in the presence of oil-soluble catalysts. During the oxidation reaction, homogeneous catalyst decomposed into nanoparticles, and heterogeneous catalyst is distributed uniformly in porous media and played an active role in the catalytic process. It should be noticed that, these kind of oil-soluble catalysts can be novel and highly potential candidates for initiation and oxidation of extra heavy oil in order to decrease the viscosity, enhanced oil recovery and production of the upgraded oil.Graphical abstract

Design of a novel ECR ion trap facility for nuclear physics and fundamental plasma processes studies

An innovative ECR ion trap facility, called PANDORA (Plasma for Astrophysics, Nuclear Decay Observation and Radiation for Archaeometry), was designed for fundamental plasma processes and nuclear physics investigations. The overall structure consists of three subsystems: a) a large (70 cm in length, 28 cm in inner diameter) ECR plasma trap with a fully superconducting B-minimum magnetic system (Bmax = 3.0 T) and an innovative design to host detectors and diagnostic tools; b) an advanced non-invasive plasma multidiagnostics system to locally characterize the plasma thermodynamic properties; c) an array of 14 HPGe detectors. The PANDORA facility is conceived to measure, for the first time, in-plasma β-decaying isotope rates under stellar-like conditions. The experimental approach consists in a direct correlation of plasma parameters and nuclear activity by disentangling - by means of the multidiagnostic system that will work in synergy with the γ-ray array - the photons emitted by the plasma (from microwave to hard X-ray) and γ-rays emitted after the isotope β-decay. In addition to nuclear physics research, fundamental plasma physics studies can be conducted in this unconventional ion source equipped with tens of detection and diagnostic devices (RF polarimeter, optical emission spectroscopy (OES), X-ray imaging, space and time-resolved spectroscopy, RF probes, scope), with relevant implications for R&D of ion sources for accelerator physics and technology. Several studies have already been performed in downsized nowadays operating ECRIS. Stable and turbulent plasma regimes have been described quantitatively, studying the change of plasma morphology, confinement, and dynamics of losses using space resolved X-ray spectroscopy.

Thin-Film Composite Membrane Compaction: Exploring the Interplay among Support Compressive Modulus, Structural Characteristics, and Overall Transport Efficiency.

Water scarcity has driven the demand for water production from unconventional sources and the reuse of industrial wastewater. Pressure-driven membranes, notably thin-film composite (TFC) membranes, stand as energy-efficient alternatives to the water scarcity challenge and various wastewater treatments. While pressure drives solvent movement, it concurrently triggers membrane compaction and flux deterioration. This necessitates a profound comprehension of the intricate interplay among compressive modulus, structural properties, and transport efficacy amid the compaction process. In this study, we present an all-encompassing compaction model for TFC membranes, applying authentic structural and mechanical variables, achieved by coupling viscoelasticity with Monte Carlo flux calculations based on the resistance-in-series model. Through validation against experimental data for multiple commercial membranes, we evaluated the influence of diverse physical parameters. We find that support polymers with a higher compressive modulus (lower compliance), supports with higher densities of "finger-like" pores, and "sponge-like" pores with optimum void fractions will be preferred to mitigate compaction. More importantly, we uncover a trade-off correlation between steady-state permeability and the modulus for identical support polymers displaying varying porosities. This model holds the potential as a valuable guide in shaping the design and optimization for further TFC applications and extending its utility to biological scaffolds and hydrogels with thin-film coatings in tissue engineering.

Nutrient Digestibility of Non-conventional Protein Sources Blend in African Catfish, Clarias gariepinus (Burchell, 1822) Post Juveniles Using Novel Aquafeed Formulation Software

In this study, the growth performance, carcass composition, and apparent digestibility coefficient of African catfish, Clarias gariepinus, were evaluated in relation to different non-conventional protein sources blends diets that were formulated using a novel feed formulation software (FUTA AQUAFEED). Diet 1 served as the control diet, and the other four experimental diets (Diets 2 through 5) included non-conventional protein sources such blood meal, water hyacinth, palm kernel cake, palm beetle meal, blackfly meal, water fern, and Moringa. The gross composition of the experimental feeds exhibited notable variations in nutrient content. The crude protein content in the diets were iso-nitrogenous. Analysis of the composition of the carcass showed that diets varied significantly. Diet 5 had the highest fat content (10.66%), while Diet 3 had the highest crude protein amount (61.57%). Growth performance parameters such as initial and final weights, weight increase, feed conversion ratio (FCR), specific growth rate (SGR), and protein efficiency ratio (PER) exhibited diverse patterns. Diet 5 produced the greatest final weight (324.00 ± 122.94 g) and weight gain (173.32 ± 96.06 g), suggesting that the varied protein blend may have advantages. Dietary differences were seen in the apparent digestibility coefficients of crude protein and lipids. The crude protein digestibility coefficient (90.68%) was best in Diet 3, while the crude lipid digestibility coefficient (92.00%) was highest in Diet 1. In conclusion, the inclusion of unconventional protein sources in the diets of C. gariepinus affects both their growth performance and nutritional makeup. Through the incorporation of alternate protein sources into fish diets, the findings offer insights for improving aquaculture techniques and advancing sustainability.

Geothermal resource potentials estimation from the interpretation of aeromagnetic data over parts of Southwestern Nigeria

In a bid to explore unconventional electricity generation sources and reduce effects of fossil fuels, this study evaluates geothermal resource potentials over parts of Southwestern Nigeria, precisely depth to the bottom of magnetic source (DBMS), heat flow, geothermal gradient and their relationships. Regional-residual anomaly separation was conducted, and spectral analysis was applied on the residual anomaly component of 14 aeromagnetic data sheets. Depth to the bottom of magnetic source varies between 1.87 and 6.26 km, with average value of 3.50 km, heat flow varies between 23.18 and 77.38 mWm−2, with average value of 43.79 mWm−2, while geothermal gradient varies between 9.27 and 30.95 oC/km with average value of 17.52 oC/km. Northcentral region has the highest heat flow (77.4 mWm−2), followed by Northeast (68.3 mWm−2), Southwest has the least (&lt; 40.0 mWm−2) while Southeast has values in between the extremes. A comparison between the average heat flow and that of ‘thermally stable’ continental regions of the world (60 or 65) mW/m2 gives 72.98 or 67.37% respectively. The estimated heat is probably from mantle plumes, radioactive sources or heat generated from pressures within basements that are overlaid by thick thermally insulated sediments, hence hot magmatic fluid flows into fractured basement and cause hydrothermal alterations of surrounding rocks. Since most geodynamic operations depends on thermal structure of the earth’s crust, the result of this study has undoubtedly contributed significantly to the body of existing thermal knowledge and closed the information gap regarding crustal temperature distribution at depth in Southwest part of Nigeria and Nigeria in general.

Anisotropic Bayesian linearized stochastic seismic inversion with multi-parameter decoupling

AbstractThe shale-oil reservoir emerges as a significant unconventional energy source, commonly predicted by anisotropic seismic inversion. Considering the intricate nature of shale-oil reservoirs, it becomes imperative to consider uncertainties during anisotropic inversion. An effective approach to address this involves stochastic inversion, specifically the anisotropic Bayesian linearized inversion (ABLI), which characterizes statistical and spatial correlations of subsurface parameters through a crucial multivariate correlation matrix constructed through geostatistics. However, an inevitable challenge in stochastic inversion arises from interference during the calibration of statistical and spatial correlations of subsurface parameters. This challenge becomes particularly pronounced in anisotropic inversion, heightened by the multitude of involved model parameters. Existing decorrelation approaches primarily address statistical correlation, neglecting the impact of spatial correlation. To tackle this issue, a novel multi-parameter decoupling strategy is proposed, formulating decoupling-ABLI (D-ABLI). D-ABLI introduces an advanced decorrelation approach, and uses principal component analysis (PCA) to simultaneously eliminate impact of statistical and spatial correlations on ABLI. The decoupling enhances the inversion accuracy of model parameters in ABLI, particularly for density and anisotropic parameters. The theoretical underpinnings of the decoupling strategy are demonstrated to be reasonable, and the effectiveness of D-ABLI is proved through a theoretical data test and a field data test regarding shale-oil reservoirs. The D-ABLI results offer the capability to estimate fracture density accurately and unveil the distribution of shale oil.

Valorisation of sulphide tailings: A novel dilute reagents-based Mn extraction process

The surging demand for manganese (Mn) and the concomitant scarcity of its primary resources have ignited interest in the extraction of this pivotal metal from unconventional sources, notably mining tailings. This study delves into the efficacy of dilute reagents as a judicious and discerning method for extracting Mn from sulphide tailings, concurrently offering environmental amelioration and substantial economic advantages. Specifically, the investigation concentrates on the adept and selective leaching of Mn from rhodochrosite (MnCO3) mineral under optimized conditions. Under the optimized conditions of 5 % HCl, a liquid-to-solid ratio of 5, a 90-minute leaching period, and a temperature at 50 °C, an exemplary 95 % leaching of MnCO3 was achieved while incurring a modest 12 % leaching of Fe, the principal impurity in the sample. Subsequent to the leaching process, MnO was efficiently extracted from the solution, exhibiting a purity surpassing 96 %, facilitated by the introduction of a diluted ammonium hydroxide solution (0.1 M NH4OH) at a solution pH of 9.8 and a temperature of 48 °C. The proposed methodology for reprocessing sulphide tailings offers numerous benefits, including cost-effective recovery and extraction, resulting from dilute reagents used and promoting a circular economy in mining. This research substantiates a significant stride towards the sustainable utilization of mining by-products, concurrently addressing both economic and environmental imperatives.