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Enhancing the rate performance of lithium-ion batteries (LIBs) is crucial to developing electronic devices. In light of the growing demand for consumer electronics, researchers have developed two-dimensional (2D) materials to achieve elevated performance levels. In this study, we applied the density functional theory (DFT) approach to assess the suitability of the novel 2D triphosphide AsP3 as a potential anode candidate for LIBs. The AsP3 monolayer exhibits high cohesive energy, outstanding structural stability, and impressive electronic properties. Our finding demonstrates that the valley site As2 is the optimal adsorption site for the Li atom on the AsP3 monolayer, with a high negative adsorption energy of -2.42 eV and considerable charge transfer. Moreover, the transition in behavior from semiconductor to metallic after the adsorption of Li on the substrate makes the AsP3 appropriate as an anode material of LIBs. Meanwhile, the AsP3 monolayer features a high theoretical storage capacity of around 638.71 mAhg− 1, exceeding that of commercial graphite and numerous other 2D materials. The diffusion barrier energy of the Li atom on the AsP3 monolayer is 0.29 eV, which is quite lower than that of many other 2D materials. This indicates rapid charge and discharge processes and underscores the high performance of the AsP3 monolayer. All these results demonstrate that the AsP3 monolayer could be a promising candidate for anode material in LIBs, paving the way for feature experimental studies in the development of battery technology. [ABSTRACT FROM AUTHOR]

This study illustrates the comprehensive investigation to assess the sedimentation, deposition pattern, and futuristic active capacity of the reservoir in a minimal period. A multi-collaborative methodology was developed using Geographic information system (GIS) & Artificial Neural Networks (ANN). The sedimentation analysis was carried out on a GIS environment using satellite rasters. The satellite data captures the live water region with a combination of visible and Near-Infrared (NIR) bands. The ANN model was developed using feed-forward backpropagation algorithm to forecast the revised water spread. A Multi-Layer Perceptron [2-1(10)-1(1)-1] ANN structure best captures the trend of water-spread reduction with the coefficient of determination (R2)1,1,1 & 0.977 for training, testing, validation, and overall performance respectively. The designed approach provides a performance comparison of GIS and ANN methods for the prediction of reservoir capacity. Also, the observations of sedimentation analysis were superimposed on the Borland & Miller graph to portray the pattern of deposition. The research framework was applied to the Kerwan reservoir located in the capital of central India. This analysis reveals that the useful capacity of the reservoir had reduced from 22.67 to 15.13 Mm3 in 46 years (1976–2022) and the depositing pattern was shifting towards Type-II (Flood Plain-Foot Hill) which was designed as Type-III like Hilly reservoir. From the Neural Network fittings, it was concluded that Kerwan would be suppressed to 59.95% in 2030 and reduced up to 49.49% & 40.84% for 2050 & 2070 respectively, if siltation carried on. [ABSTRACT FROM AUTHOR]

Conserving rainwater at the household level is generally overlooked in many developing countries. Therefore, rooftop rainwater potential for kitchen gardening or aquifer recharge was explored using 30 years of weather data in the Rawal watershed, which is facing water table decline (> 1 m/year) due to urbanization and climate change. The results revealed that harvesting rainwater from rooftops of available household sizes (single to five-room) in the Rawal watershed area is capable of growing vegetables (onion, tomato, cucumber, and garlic) on 25 (1 Marla) to 1339 m2 (53 Marla) using storage tanks of suitable capacity (10 to 59 m3). Furthermore, by recharging the groundwater through the available rainwater of around 1.2 m per year can stop or reduce the current water table decline in the study area. Rainwater storage during the monsoon can increase productivity by reusing in dry periods while recharging aquifers can sustain flow from springs, dug wells, and tube wells in rural and urban areas. The new information and knowledge can be helpful for decision support in designing site-specific rooftop rainwater harvesting systems for kitchen gardening, which can be instrumental in improving food security and raising groundwater levels in both urban and rural areas. [ABSTRACT FROM AUTHOR]

Herein, the electronic and magnetic properties of 2D M3C2S2 (M = Cr, Zr) monolayers and their potential as lithium-ion battery electrodes are systematically studied by density functional theory (DFT). The geometric structures of the M3C2S2 monolayers are both thermally and dynamically stable. The Cr3C2S2 monolayer acts as a magnetic metal, while the Zr3C2S2 monolayer shows a nonmagnetic metallicity nature. The diffusion energy barriers are only 0.23 eV (Cr3C2S2) and 0.26 eV (Zr3C2S2), and lithium storage capacities are 439.35 mA h g−1 for the Cr3C2S2 monolayer and 296.41 mA h g−1 for the Zr3C2S2 monolayer, respectively. Compared with the pristine M3C2 monolayers, although the diffusion energy barriers are slightly increased after the S group modification, the lithium storage capacity of Cr3C2S2 and Zr3C2S2 monolayers both have obvious improvement. Our work indicates that the S-functionalized M3C2S2 hold promise for future use as electrode materials for Li-ion batteries. [ABSTRACT FROM AUTHOR]

As concerns about environmental pollution grow, hydrogen is gaining attention as a promising solution for sustainable energy. Researchers are exploring hydrogen's potential across various fields including production, transportation, and storage, all thanks to its clean and eco-friendly characteristics, emitting only water during use. One standout option for hydrogen storage is through gas hydrates, unique structures mainly composed of water molecules. These hydrates have attracted interest as a green method for storing hydrogen. A noteworthy advantage is that they release only water vapor when used, aligning with environmental goals. However, ongoing research is essential to improve how efficiently these hydrates form under different conditions. This review paper offers a comprehensive overview of research into using gas hydrates for hydrogen storage. While early efforts focused on storing pure hydrogen, current studies delve into modifying the conditions and speeds of the formation using various promoters that impact the thermodynamics and kinetics involved. Some researchers suggest new strategies that enable trapping multiple hydrogen molecules within a single hydrate cage, potentially enhancing hydrogen storage capacity. Moreover, the use of materials such as porous substances, surfactants, and amino acids has been extensively investigated to enhance interactions between water and gas, resulting in accelerated formation rates. By advancing these strategies, gas hydrates could become a more practical material for hydrogen storage. Given the urgency of reducing carbon emissions and curbing environmental harm, gas hydrates stand out as a promising option for sustainable energy advancement. [ABSTRACT FROM AUTHOR]

The Mishrif sequence in the West Qurna oilfield is a long-term, second-order shallowing-upward cycle with a regional unconformity at the top. Due to changes in rock textures and pore types, permeability in the Mishrif is highly variable (ranging from < 0.01 to > 1000 mD) and does not generally correlate well to porosity. Nevertheless, there is generally a good correspondence between depositional texture and their respective sequence-stratigraphic position and reservoir quality. In this study, Reservoir Rock Typing (RRT) was modified according to core data, depositional model, and diagenesis controls that were recorded recently to characterize permeability variations, linking it to the geological processes controlling the initial depositional fabric and the subsequent diagenetic overprint then the storage capacity was re-estimated according to these changes. The results show that the sequence stratigraphic model for the Mishrif Formation in the West Qurna/1 oilfield reflects six Reservoir Rock type groups. Grainstone and rudstone are the most abundant in the Highstand to late Highstand of the Upper Mishrif (mA) and the Middle Mishrif (mB). High flow zones in the upper unit of the Middle Mishrif (mB1) are confined to channels and spillover lobes. Microporous RRT 1 and RRT 2 are most abundant in the transgressive phases of the Lower Mishrif (mC) and the bottom of the Middle Mishrif (mB2L). In RRT 0, it is also the toes of the clinoforms exist to represent the vertical baffles of flow. RRT 00, the “cap rock intervals,” are generally developed below third-order sequence boundaries, forming widespread vertical barriers to flow. The results indicate clearly that the Grainstones and Microporous layers have about 70% of the total reserves in this Formation. Due to the complexity of the Mishrif Reservoir and limited test data, many uncertainties remain, such as mA geologic understanding, mB1 tidal channels, mB2L complexities and uncertainties, property degradation from top to bottom and from northeast to southwest, and depositional environment of clinoforms. [ABSTRACT FROM AUTHOR]

In the realm of modern cryptography and anti-counterfeiting, innovative approaches are crucial to encode sensitive information securely. Tailored responsive structural colors have garnered significant interest due to their feature-rich spectra and high sensitivity to external stimuli. However, high costs and complex processing involved in integrating the various delicate microstructures have impeded their widespread development. In this study, we present a straightforward multilevel chromatic encryption scheme utilizing direct-writing gradient-crosslinked microdomes. The solvent-responsive structural color of each microdome, arising from the synergistic effect of total internal reflections and interference, is adjusted independently across the entire visible region. Each microdome functions as a signal recording unit, enabling multilevel color variations through a solvent-dependent development step. This approach facilitates the encoding of enhanced information into a single pixel. To demonstrate the efficacy of our method for advanced applications, we have prepared a collection of solvent-dependent multilevel codes for algorithm cryptography, showcasing its potential for high-level anti-counterfeiting and high-density optical data storage. [ABSTRACT FROM AUTHOR]

Reduction in greenhouse gas emissions into the environment is a key pre-requisite for ensuring a healthy and sustainable planet that we all yearn for. The most prominent of all technologies devised by experts worldwide to tackle this menace and bring great cuts is the Carbon Capture and Sequestration (CCS) technology. Unfortunately, in the present Africa, this novel technology is not being utilized maximally. Carbon dioxide storage capacity estimation in the past has also been restricted solely to petrophysical and lithological information and not performance-based numerical simulation to assess or quantify the storage efficiency. Thus, the use of advanced geomodeling technique has been employed in this research to investigate the injectivity and simulation capacities for effective carbon dioxide sequestration in the 'X-Field', Central Swamp II depobelt of the Niger Delta. The ECLIPSE compositional reservoir simulator (E300) software was used for this research using a 50 year simulation period for the target reservoir (Reservoir J). The cumulative storage capacity for Reservoir J yielded an estimate of 7.01 Bsm3 at a bottom hole pressure (BHP) of 1455 psi using the existing wells as injection wells. The results of relative permeability correlation show that there is no significantly large difference between the behavior of the drainage curves. At high water saturation end, the relative permeability of gas becomes high in the reservoir under high capillary pressure at the start of gas invasion. The curves in drainage tend to show capillary end effect at the lower water saturation end. Generally, the reservoir shows higher relative permeability of gas than water at higher capillary pressure although the relative permeabilities of both phase show similar behavior under the same capillary pressure, which suggests that the reservoir rocks tend to more gas wet than water wet under higher capillary pressure, making it suitable for geological storage of CO2. However, beyond the target BHP, it is possible that the reservoir could approach fracture pressure if injection continues. Also, at relaxation time, the pressure is predicted to remain constant resulting in a slight decrease in the motion of the CO2 fluid. Besides providing a better understanding of reservoir behavior in the Niger Delta during CCS, this research demonstrates that for an effective CCS project in the Niger Delta region to take place, a performance-based storage capacity estimation and an efficient injection strategy with a well-planned well placement is paramount. [ABSTRACT FROM AUTHOR]

In this work, we have investigated the electrochemical characteristics of armchair silicon carbide nanoribbon (ASiCNR) for its potential deployment as 2D lithium-ion battery anode material. Density functional theory approach is used to calculate the adsorption energy, storage capacity, and open circuit voltage of ASiCNR for LIB. Adsorption of Li atoms introduces the new energy bands which cross the Fermi level; this results in semiconductor to metallic transition of ASiCNR. It indicates the strong interaction of Li atoms towards the ASiCNR. When adsorption of Li atoms increases one by one, the adsorption energy (E ads ) per Li atoms increases gradually. When all favourable sites are adsorbed by Li atoms E ads reached its maximum value and it results in maximum storage capacity of 818 mAhg - 1 and open circuit voltage of 1.15 V. Diffusion barrier of Li atoms for the substrate is 0.42 eV. Our computational results suggest that ASiCNR can be used as an anode material for Li-ion batteries, and it provides the theoretical background for the future study on ASiCNR and other Li storage structures. [ABSTRACT FROM AUTHOR]

Sediment deposition in water reservoirs has major implications for storage capacity, reservoir lifetime, and water quality. Changes in rainfall patterns and land use will consequently alter the rate of erosion and therefore have a direct effect on sedimentation rates. This literature review employed a systematic mapping approach to collate and describe evidence of contemporary sedimentation trends for impounded reservoirs and natural lakes with emphasis on studies which analysed impacts on water storage capacity. Fourteen studies determined an overall increase in sedimentation rate, 13 identified a recent decline and another 5 reported mixed results. Interestingly, 83.3% of the articles that studied natural lakes found an increase in recent contemporary sedimentation, while 54.5% of the articles on impounded reservoirs indicated recent declines in sediment deposition. Land use change was the main causative factor responsible for sedimentation rate increase followed by the combined effects of land activities and climate change. Soil and sediment management strategies, implemented in and upstream of some impounded reservoirs, have proved to be effective in mitigating and remediating reservoir sedimentation. From the 147 papers preselected, only 33 contain sufficient sedimentation data to infer recent rate trends with only about 45% of these articles reporting quantities of storage capacity loss caused by sedimentation. Across these 33 studies, assessments of sedimentation and associated storage capacity loss are compromised by the limited spatiotemporal resolution of current measurement methods, reinforcing the requirement to develop new, more robust techniques to monitor sedimentation and storage capacity changes. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) storage capacity is the main criterion for assessing CO2 geological storage. Based on actual data from the Shiqianfeng formation in the Ordos Basin, three-dimensional (3D) models were built using the TOUGHVISUAL visualization software and simulated using the TOUGH2 integral finite difference modeling code with the ECO2N fluid property module to explore the impact of formation attributes (formation slope) and controllable factors (injection temperature) on CO2 storage capacity. A total of 16 schemes were designed, with four injection temperatures (24 ℃, 31 ℃, 38 ℃, and 45 ℃) and four formation slopes (0°, 5°, 10°, and 15°). Simulation results showed that the injection temperature and formation slope both had a significant influence on CO2 storage capacity. The impact of injection temperature on the total storage amount was more obvious than that of the impact of formation slope. A higher injection temperature resulted in a greater total storage amount. Increasing the formation slope and injection temperature increased the gas-phase, dissolved-phase, and total CO2 storage amounts in the upper left section of the injection well, but decreased them in the lower right part of the injection well. The impact of formation slope on the conversion rate from gas-phase CO2 to dissolved-phase CO2 was more obvious than the impact of injection temperature. A steeper formation slope resulted in a higher conversion rate. A smaller formation slope and a higher injection temperature should be selected to store CO2. [ABSTRACT FROM AUTHOR]

Background and aims: According to the carbon (C) saturation concept, the capacity of soils to accumulate stabilized organic C is limited by the number of binding sites on mineral surfaces. The concept and its application are highly debated. Therefore, we aimed at testing this theory using field experimental data.Soils were sampled from four long-term field experiments with different amounts of organic fertilisation going up to extreme high C inputs (20 Mg C ha−1 yr−1) five times higher than in common agricultural practice. Soils were fractionated by particle size to obtain sand-sized, coarse silt and fine silt plus clay fractions.We found a linear relation between C input and soil organic carbon stocks (SOC) even with vast amounts of organic C inputs to the soil at three experimental sites. Across all experiments, C stocks in the sand-sized fraction increased on average by 146%, whereas C stocks in the fine silt plus clay fraction (< 20 µm) increased by just 17% without distinct saturation behaviour. The C sequestration efficiency (amount of C retained as SOC per amount of C input) tended to increase with initial SOC content which is not in line with the saturation theory.The experiments were subject to C inputs via organic fertilisation that would and should rarely be reached in agricultural practice due to negative side effects. Even under these artificial conditions experiments did not show a distinct saturation behaviour.Initial SOC stocks or SOC in the mineral-associated fraction did not appear to limit the potential of soils to sequester additional SOC. It can be concluded that C sequestration is mainly limited by the availability of C inputs from biomass.Methods: According to the carbon (C) saturation concept, the capacity of soils to accumulate stabilized organic C is limited by the number of binding sites on mineral surfaces. The concept and its application are highly debated. Therefore, we aimed at testing this theory using field experimental data.Soils were sampled from four long-term field experiments with different amounts of organic fertilisation going up to extreme high C inputs (20 Mg C ha−1 yr−1) five times higher than in common agricultural practice. Soils were fractionated by particle size to obtain sand-sized, coarse silt and fine silt plus clay fractions.We found a linear relation between C input and soil organic carbon stocks (SOC) even with vast amounts of organic C inputs to the soil at three experimental sites. Across all experiments, C stocks in the sand-sized fraction increased on average by 146%, whereas C stocks in the fine silt plus clay fraction (< 20 µm) increased by just 17% without distinct saturation behaviour. The C sequestration efficiency (amount of C retained as SOC per amount of C input) tended to increase with initial SOC content which is not in line with the saturation theory.The experiments were subject to C inputs via organic fertilisation that would and should rarely be reached in agricultural practice due to negative side effects. Even under these artificial conditions experiments did not show a distinct saturation behaviour.Initial SOC stocks or SOC in the mineral-associated fraction did not appear to limit the potential of soils to sequester additional SOC. It can be concluded that C sequestration is mainly limited by the availability of C inputs from biomass.Results: According to the carbon (C) saturation concept, the capacity of soils to accumulate stabilized organic C is limited by the number of binding sites on mineral surfaces. The concept and its application are highly debated. Therefore, we aimed at testing this theory using field experimental data.Soils were sampled from four long-term field experiments with different amounts of organic fertilisation going up to extreme high C inputs (20 Mg C ha−1 yr−1) five times higher than in common agricultural practice. Soils were fractionated by particle size to obtain sand-sized, coarse silt and fine silt plus clay fractions.We found a linear relation between C input and soil organic carbon stocks (SOC) even with vast amounts of organic C inputs to the soil at three experimental sites. Across all experiments, C stocks in the sand-sized fraction increased on average by 146%, whereas C stocks in the fine silt plus clay fraction (< 20 µm) increased by just 17% without distinct saturation behaviour. The C sequestration efficiency (amount of C retained as SOC per amount of C input) tended to increase with initial SOC content which is not in line with the saturation theory.The experiments were subject to C inputs via organic fertilisation that would and should rarely be reached in agricultural practice due to negative side effects. Even under these artificial conditions experiments did not show a distinct saturation behaviour.Initial SOC stocks or SOC in the mineral-associated fraction did not appear to limit the potential of soils to sequester additional SOC. It can be concluded that C sequestration is mainly limited by the availability of C inputs from biomass.Conclusion: According to the carbon (C) saturation concept, the capacity of soils to accumulate stabilized organic C is limited by the number of binding sites on mineral surfaces. The concept and its application are highly debated. Therefore, we aimed at testing this theory using field experimental data.Soils were sampled from four long-term field experiments with different amounts of organic fertilisation going up to extreme high C inputs (20 Mg C ha−1 yr−1) five times higher than in common agricultural practice. Soils were fractionated by particle size to obtain sand-sized, coarse silt and fine silt plus clay fractions.We found a linear relation between C input and soil organic carbon stocks (SOC) even with vast amounts of organic C inputs to the soil at three experimental sites. Across all experiments, C stocks in the sand-sized fraction increased on average by 146%, whereas C stocks in the fine silt plus clay fraction (< 20 µm) increased by just 17% without distinct saturation behaviour. The C sequestration efficiency (amount of C retained as SOC per amount of C input) tended to increase with initial SOC content which is not in line with the saturation theory.The experiments were subject to C inputs via organic fertilisation that would and should rarely be reached in agricultural practice due to negative side effects. Even under these artificial conditions experiments did not show a distinct saturation behaviour.Initial SOC stocks or SOC in the mineral-associated fraction did not appear to limit the potential of soils to sequester additional SOC. It can be concluded that C sequestration is mainly limited by the availability of C inputs from biomass. [ABSTRACT FROM AUTHOR]

The Aznalcóllar tailings pond failure (1998) is regarded as one of the severe ecological mine disasters ever reported. The spill of the mine tailings affected more than 60 km of the Agrio and Guadiamar rivers and caused major environmental damage. Despite the event being well-documented with more than 400 scientific publications, including two special issues and two reviews, several hydraulic uncertainties and inconsistencies remain. This paper conducts a state-of-the-art review of the most relevant hydraulic aspects of the mine disaster. It addresses the pond and fluid characteristics, the break type, the breaking time, the flow propagation, the volume potentially stored and subsequently spilled, area dimensions affected by the spill, and the morphological changes generated in the river and riverbanks caused by the spill, and later on by the restoration activities. Several discrepancies and plenty of controversial data have been unearthed that may affect general understanding of the event. In addition, new data is introduced and analysed applying photointerpretation and digital terrain analysis techniques, aiming to derive in essential hydraulic parameters. The most important findings are that the spill could have had a volume about 11.5 hm3, affecting about 86.7 km of river length, twice the most referenced values in the literature, and that applied restoration activities have substantially modified the hydro-sedimentary processes of the affected system. Additionally, a first video observation-based classification reveals that the fluid behaved more like a highly concentrated sediment-laden flow than like a mud flow. [ABSTRACT FROM AUTHOR]

The aim of the study is to investigate the influence of geometry on the thermal capacity and stratifications of a water pit heat storage for solar district heating. A TRNSYS component model for a truncated cone water pit was developed based on the coordinate transformation method and validated by experimental results from the water pit heat storage in Huangdicheng in 2018. The thermal performance of 26 water pits with different heights and side wall slopes was calculated for 10 consecutive years. It takes four to six years for the water pit to reach steady-state operation. The operation data from the tenth year was selected to evaluate the thermal performance of each configuration. The results show that because of the thermal insulation on top of the water pit, the height to diameter ratio of a water pit with minimum annual heat loss was always smaller than 1.0. The annual storage efficiency of a water pit increases with side wall slope due to the reduced side wall area. There is an almost linear increase in the thermal stratification number of a water pit with height. With an increase in the height, thermal stratification in water pits with a steeper slope increased more gradually than water pits with a lower slope. The findings in this paper are relevant for the design optimization of water pits as seasonal thermal energy storages. [ABSTRACT FROM AUTHOR]

Periodical monitoring is needed for reservoirs to ensure proper management against sedimentation. The amount of sediment retained by the reservoir or the amount of volume lost is the major factor to be assessed during monitoring. This study assesses the reservoir sedimentation of the Wellington Reservoir using Satellite Remote Sensing. The analysis was carried out using eight sentinel 2 images for the hydrologic years 2016–2017. The water spread area was acquired from satellite data based on supervised classification. The water level was found to be in fluctuation between 1.94 and 4.94 m in the period of data. Polynomial regression equations were used in finding the relation between the depths: water spread area and volume of reservoir. From the study, it was found that due to sedimentation, the gross storage capacity of the Wellington Reservoir has reduced from 73.05 to 52.56 Mm3 and the loss due to sedimentation is 28.04% in 92 years. [ABSTRACT FROM AUTHOR]

When originally developed, the Koval theory was meant to interpret the core-scale production of oil by a miscible displacement by solvent injection. An essential parameter in the theory is the Koval factor, KV, which combines both the viscosity contrast effect (E) and the heterogeneity effect (HK) as KV = E HK. The Koval method has done an excellent job of interpreting oil recovery; however, the physical origin of this simple model is not clear. To address the physical significance of these factors, this paper explains a novel approach to derive the Koval factor using petrophysical data and vertical equilibrium theory. The study examines core data from 112 vertical production wells from fields located in the United States and Algeria. The heterogeneity factor is estimated from the flow- and storage-capacity relations, according to the Koval theory. Then, using fractional flow theory and assuming vertical equilibrium, we derive a mathematical expression that conveys the physical interpretation of the Koval factor. The results indicate that the physical explanation of the Koval factor is that of a product of the mobility ratio and the heterogeneity of the reservoir. The Koval factor simplifies computations of oil recovery by transforming the original reservoir to one with uniform layers, in vertical equilibrium, and piston-like displacement within each using only the flow and storage capacities. The physical interpretation of the Koval factor could offer new insights to examine previous results obtained from the theory itself. [ABSTRACT FROM AUTHOR]

Over the past 2 years, a great progress in petroleum and gas exploration has been made in tight lacustrine carbonate rocks of E32 in the Yingxi area. Many high-yield commercial oil flow wells with more than 1000 tons of oil production per day have been found, but their reservoir space type and storage capacity are the key issues highly concerned and disputed by many explorationists. According to the study on systemic petrology and mineralogy, analysis of physical property, study on capillary pressure curve, analysis of ultra-micro crystal morphology, analysis of micro-area geochemical composition, and other comprehensive analysis, and pore types of the E32 reservoir are mainly intercrystalline pores of dolomite, and a small number of dissolution phenomena have been found. Therefore, large-scale oil and gas reservoirs can be formed. The analysis involves these key results and evidences: (1) under the microscope and scanning electron microscope, many intercrystalline pores are developed in dolomite rocks, presenting a "high-wide platform" phenomenon on the capillary pressure curves to imply "small bore—large quantity". (2) The electron probe shows that the molecular formula of dolomite is Ca(Mg0.96Fe0.04)(CO3)2. In the penecontemporaneous dolomitization process, intercrystalline pores come from volume shrinkage when Mg2+ ions replace Ca2+ ions, and a small number of Fe2+ ions are involved in this chemical reaction. The 13.36% plane porosity can be formed in ideal conditions. (3) According to the statistical data, intercrystalline pores are enlarged by organic acids in several samples, no evidence is available for leaching dissolution of atmospheric water because of exposure, and many types of feldspar do not dissolve. The reservoir rocks are formed due to a high deposition rate. (4) According to the measured pore sizes and the values based on the chemical theory, the pore size is in the range of 0.4–1.07 μm. These pores can store all oil, gas, and symbiosis substances, which can flow or migrate in the pores because of the pore sizes. The pictures of fluorescence thin sections and the backscattered electron images of SEM show that these micro-pores are full of hydrocarbons, creating the oil and gas accumulation pattern of "containing oil for the whole sag" and "producing oil for each well" in the Yingxi area. Based on the oil and gas accumulation model, the Yingxi area is an integrated oil and gas field with the most potential and industrial value in Qaidam Basin. The research results are crucial to the petroleum and gas exploration of carbonates in a saline lacustrine basin. [ABSTRACT FROM AUTHOR]

For the issue of beautification and capacity expansion of the Quick Response(QR) code, we proposed an algorithm based on sequential module modulation. First, the modules for the padding codewords are modulated by the module-based binarized background image. Then, to increase the storage capacity, low-pass textured patterns are designed for both the black modules and the white modules. The modules of the plain QR code are modulated by the second-level message. Finally, these modulated modules are further modulated by the L-channel of the background image in Lab color space. The module elimination parameter in the second modulation is optimized to maximize an objective function that accounts for both the visual quality and the decoding error. Experimental results demonstrate that, the proposed algorithm is superior to the reference method in terms of visual quality and capacity. [ABSTRACT FROM AUTHOR]

In this work, the effects of three ionic liquids (ILs), namely, 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium dicyanamide and tetraethyl-ammonium chloride, on methane hydrate formation and dissociation kinetic parameters were studied. The kinetic parameters including the initial rate of hydrate formation, hydrate stability at atmospheric pressure and hydrate storage capacity were evaluated. The experimental measurements were performed in an initial pressure range of 3.5–7.1 MPa. It was found that both of ILs with imidazolium-based cation increase the initial methane hydrate formation rate while the IL with ammonium-based cation leads to a decrease in the initial methane hydrate formation rate. It was also interpreted from the results that all of the three studied ILs decrease methane hydrate stability at atmospheric pressure and increase methane hydrate storage capacity. Finally, both of ILs with imidazolium-based cations were found to have higher impacts on decreasing hydrate stability at atmospheric pressure and increasing the methane hydrate storage capacity than the applied IL with ammonium-based cation. [ABSTRACT FROM AUTHOR]

The accumulation of electrolytic hydrogen synthesized in a 5 M KOH solution by double- and triple-walled carbon nanotubes (CNTs) deposited on a steel membrane and encapsulated by an electrolytic iron layer of the thickness of 10 nm was studied. CNTs were synthesized by catalytic pyrolysis of methane and are characterized by an inner diameter of 2-4 nm, a length of up to 10 μm and more, and a specific surface area of 600-800 m2 g-1. The studies were performed by electrochemical diffusion, cyclic voltamperometry, and electrochemical-impedance spectroscopy. It has been shown that the hydrogen-storage capacity in CNTs varies in the range of 4-25% depending on the content of nanotubes in the composite. [ABSTRACT FROM AUTHOR]

Deep saline aquifers widely distributed deep in the earth offer the greatest CO storage potential in all current geological CO storage approaches. The western region of the Saharan platform in Algeria includes several sedimentary basins characterized by a large production of dry gas with high CO rates sometimes exceeding 9 %. To reduce CO emissions, these basins were analyzed to identify those with the largest potential for the geological sequestration of CO (GSC). The evaluation methodology applied to determine the basin potential is based on qualitative geological and practical criteria to which we have assigned normalized numerical values. This evaluation method allows us to quantitatively compare and evaluate the basins in Algeria. Estimations of the CO storage capacities of several structures in the sedimentary Ahnet-Gourara Basin, which has the greatest potential for GSC, vary from 1 Gt to over 5 Gt. Based on cautious estimations, these geologic structures should be able to contain the entire volume of the CO emitted over the next three decades at least. [ABSTRACT FROM AUTHOR]

We study various models of associative memories with sparse information, i.e. a pattern to be stored is a random string of 0s and 1s with about $$\log N$$ 1s, only. We compare different synaptic weights, architectures and retrieval mechanisms to shed light on the influence of the various parameters on the storage capacity. [ABSTRACT FROM AUTHOR]

Large-scale CO injection problems have revived the interest in simple models, like percolation and vertically-averaged models, for simulating fluid flow in reservoirs and aquifers. A series of such models have been collected and implemented together with standard reservoir simulation capabilities in a high-level scripting language as part of the open-source MATLAB Reservoir Simulation Toolbox (MRST) to give a set of simulation methods of increasing computational complexity. Herein, we outline the methods and discuss how they can be combined to create a flexible tool-chain for investigating CO storage on a scale that would have significant impact on European CO emissions. In particular, we discuss geometrical methods for identifying structural traps, percolation-type methods for identifying potential spill paths, and vertical-equilibrium methods that can efficiently simulate structural, residual, and solubility trapping in a thousand-year perspective. The utility of the overall workflow is demonstrated using real-life depth and thickness maps of two geological formations from the recent CO Storage Atlas of the Norwegian North Sea. [ABSTRACT FROM AUTHOR]

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Enhanced oil recovery through carbon dioxide injection (CO-EOR) data has made it possible to estimate the CO geological storage in the oilfields of the Songliao Basin, northeastern China. The storage capacity of CO in oilfields was determined and the results show that the theoretical storage capacity of CO in the oilfields of the Songliao Basin is 2.36 × 10 t, and the effective storage capacity is 0.59 × 10 t with an effective coefficient of 0.25. Among the tectonic units, the central downwarp has the highest storage capacity of 2.17 × 10 t, which accounts for 91.8% of the total storage capacity. On the other hand, the western slope area has a storage capacity of 0.13 × 10 t, which accounts for only 5.6% of the total storage capacity. Thus, the central downwarp and western slope together comprise about 97.4% of the total storage capacity, and these areas could be selected as potential areas for CO geological storage in the oilfields of the Songliao Basin. Furthermore, the oilfields can be used as target formations to store CO for about 10 years as per the estimated effective storage capacity, and 40 years according to the theoretical storage capacity. Although, the uncertainty analysis of the parameters yielded the cursory estimated results of the CO storage capacity, the prospect selection for the CO sequestration in the oilfields of the Songliao Basin is feasible based on the assessment scale. [ABSTRACT FROM AUTHOR]

CO2 sequestration in deep saline aquifers has proven to be one of the most promising options to reduce anthropogenic CO2 emissions. Sedimentary basins are chosen as targets of CO2 sequestration due to the existence of deep saline aquifers. This paper presents the first systematic investigation on the occurrence and characteristics of potential reservoirs for CO2 sequestration in deep saline aquifers in the Bohai Bay Basin (BBB) and offers detailed estimates on the storage capacity within the depth range from 800 to 3500 m. A preliminary suitability assessment for preferential sites is also presented. Geological analyses show that deep saline aquifers in Guantao formation (Ng) of Neogene, Dongying (Ed) and Shahejie formations (Es1, Es2, Es3, Es4) of Paleogene are potential reservoirs. Deep saline aquifers in the BBB may accommodate about 3922 Mt CO2 with 50 % confidence level, according to a modified CSLF (Carbon Sequestration Leadership Forum) method. The CO2 storage capacity of individual depression varies from 65 Mt (Liaohe depression) to 934 Mt (Liaodongwan-Bozhong depression). The Guantao formation (Ng) of Neogene is a regionally distributed reservoir with low TDS (Total Dissolved Solids) and favorable depth and thickness, the capacity of which accounts for 84 % of the total and is therefore considered as the most promising reservoir. Preliminary suitability assessment is carried out in terms of sedimentology, tectonic stability, geothermal conditions, saline water characteristics, potentially conflicting resources development as well as CO2 emission sources. The Liaodongwan & Bozhong, Jiyang & Changwei and Huanghua depressions are chosen as the most suitable sites for CO2 storage. Jizhong and Liaohe depressions are less suitable while Linqing depression is not suitable due to its lower tectonic stability, geological information and CO2 emission sources. Although uncertainties exist, the estimate in this study is significant for future study and implementation of CO2 sequestration in the basin. [ABSTRACT FROM AUTHOR]

Recreational boating is an important economic activity that can also represent a powerful source of interference for biological communities. The monitoring of the recreational boating in all Marine Protected Areas (MPAs) within the Liguria region was conducted in the 2010 summer season and it allowed to obtain information not provided by any official institution. The collaboration of geographically different MPAs in Liguria has led to the implementation of a monitoring framework of recreational boating, and this has made it possible to develop uniform management strategies for all the Ligurian marine parks. This study identifies the optimal number of boats for each MPAs, the number of boats that can anchor in the various parks without creating any impact on the biocenosis of merit, providing a first characterization of recreational boating in Liguria during the high touristic season and providing management recommendation to each MPAs. Generally, the Ligurian MPAs do not present critical situations, the number of boats in each MPA being below the optimal number, with the exception of Portofino MPA, where in the 12.5 % of monitored days more than 220 boats were counted and the mean density for weekend is 1.19 no boats/ha (4 times higher than weekday). The results confirm the dependence of the boats peaking from the holidays and the months of the summer, but also it highlights other factors that can contribute in the choice of the boaters. [ABSTRACT FROM AUTHOR]

In this paper, the storage capacity of communication among cores and processors is taken into account and a maximum D-value-first algorithm is proposed. By improving the hardware parallelism in the task execution process, the maximum storage requirements for communication are minimized. Experimental results with various directed acyclic graph models showed that compared with the earliest-task-first algorithm, the storage requirements for communication were reduced by 22.46%, on average, while the average of makespan only increased by 0.82%. [ABSTRACT FROM AUTHOR]

Storage capacity is a key aspect when validating potential CO sequestration sites. Most CO storage projects, for obvious reasons, target conventional aquifers (e.g., saline aquifers, depleted hydrocarbon fields) with good reservoir properties and ample subsurface data. However, non-geological factors, such as proximity to the CO source, may require storing CO in geologically 'less-than-ideal' sites. We here present a first-order CO storage resource estimate of such an unconventional storage unit, a naturally fractured, compartmentalized and underpressured siliciclastic aquifer located at 670-1,000 m below Longyearbyen, Arctic Norway. Water injection tests confirm the injectivity of the reservoir. Capacity calculations, based on the US DOE guidelines for CO storage resource estimation, were implemented in a stochastic volumetric workflow. All available data were used to specify input parameters and their probability distributions. The areal extent of the compartmentalized reservoir is poorly constrained, encouraging a scenario-based approach. Other high-impact parameters influencing storage resource estimates include CO saturation, CO density and the storage efficiency factor. The hydrodynamic effects of storing CO in a compartmentalized aquifer are accounted for by calculating probable storage efficiency factors (0.04-0.79 %) in a fully closed system. The results are ultimately linked to the chosen scenario, with two orders of magnitude difference between scenarios. The fracture network contributes with up to 2 % to the final volumes. The derived workflow validates CO storage sites based on initial feasibility assessments, and may be applied to aid decision making at other unconventional CO storage sites with significant data uncertainty. [ABSTRACT FROM AUTHOR]

The northern part of Cyprus is usually characterized by its small watersheds and the lack of ephemeral surface water resources. Therefore, all the water dependent activities depend on groundwater resources. Kyrenia Range subaquifers are the only natural domestic water supplying sources, fulfilling the required worldwide drinking water quality standards. In the present study, various hydrogeological factors that could influence the aquifer recharge and abstraction are used together with annual groundwater level changes, to estimate the capacity of each subaquifer distributed at the Kyrenia Range randomly. During the analyses, 11 subaquifers are worked out; and their spatial distribution, the depth, and the daily abstraction from the available wells are surveyed. The results show that annual groundwater recharge into the subaquifers is 1126 mm. It is also observed that the subaquifers recharging from the southern foothills are more vulnerable to climate effects than the ones at the northern foothills. The available water storage at the present situation, at each subaquifer, is calculated individually and finally the total storage capacity of Kyrenia Range subaquifers, is assessed as 214 million cubic meters (MCM); whereas the data analyses show that annual abstractions from the 11 subaquifers is 13.34 MCM, annually. [ABSTRACT FROM AUTHOR]

In this study, chemically and electrochemically derived graphenes (CG and EG) were synthesized to form manganese dioxide (α-MnO)/graphene nanocomposite cathode material for zinc primary cell. The discharge capacity of prepared nanocomposites was studied using Swagelok-type cell setup, where α-MnO/graphene was used as a cathode and zinc as an anode along with an electrolyte (ZnCl). Electrical conductivity and discharge behaviors of the CG and EG samples were studied in detail. The EG sample showed a high discharge capacity of 337 mAh g, whereas the CG sample showed a discharge capacity of 205 mAh g . More importantly, the discharge capacity of the EG sample-based cathode was 64 % higher than that of the CG sample-based cathode. The above observation suggests that EG sample serves as an effective cathode material for zinc-based primary battery applications. [ABSTRACT FROM AUTHOR]

Pressure buildup limits CO injectivity and storage capacity and pressure loss limits the brine production capacity and security, particularly for closed and semi-closed formations. In this study, we conduct a multiwell model to examine the potential advantages of combined exhaustive brine production and complete CO storage in deep saline formations in the Jiangling Depression, Jianghan Basin of China. Simulation results show that the simultaneous brine extraction and CO storage in saline formation not only effectively regulate near-wellbore and regional pressure of storage formation, but also can significantly enhance brine production capacity and CO injectivity as well as storage capacity, thereby achieving maximum utilization of underground space. In addition, the combination of brine production and CO injection can effectively mitigate the leakage risk between the geological units. With regard to the scheme of brine production and CO injection, constant pressure injection is much superior to constant rate injection thanks to the mutual enhancement effect. The simultaneous brine production of nine wells and CO injection of four wells under the constant pressure injection scheme act best in all respects of pressure regulation, brine production efficiency, CO injectivity and storage capacity as well as leakage risk mitigation. Several ways to further optimize the combined strategy are investigated and the results show that increasing the injection pressure and adopting fully penetrating production wells can further significantly enhance the combined efficiency; however, there is no obvious promoting effect by shortening the well spacing and changing the well placement. [ABSTRACT FROM AUTHOR]

In this paper, the impact of storage capacity usage and predictable contact schedule on dynamic routing is studied for the Opportunistic Deep Space Backbone Layer (OppDSBL) of the Deep Space Information Networks. The hypergraph model is firstly constructed to represent the OppDSBL for the sake of the improvement towards the network connectivity. Also, a polynomial time algorithm of dynamic routing in the OppDSBL is proposed, which realizes joint routing selection, storage capacity usage and predictable contact schedule simultaneously. The proposed algorithm depends on two novel models, i.e., the dynamic storage capacity usage model (DSCUM) and the predictable contact schedule model (PCSM). In the DSCUM, a general infinite-horizon differential game model for dynamic storage capacity usage of joint node is implemented based on two cost functions, which indicates the reduction as well as the consumption of storage capacity. Moreover, an optimization problem is further designed by taking into account the impact of selfish behavior on the dynamic storage capacity usage, and a set of optimal strategies to the noncooperative dynamic storage capacity usage is also obtained. In the PCSM, the predictable contact interruption probability is explicitly quantified to estimate the likelihood of link outage. In addition, the predictable contact schedule metric is further formulated to describe the contact relationship among different isolated islands in hypergraph model. Theoretical analysis and numerical results demonstrate the effectiveness and feasibility of the proposed dynamic routing algorithm. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology Journal is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Formulas are presented for determining corrections to the storage capacity of vertical steel cylindrical tanks, conditioned by change in the hydrostatic pressure of a column of fluid contained within the limits of each band of the reservoir. [ABSTRACT FROM AUTHOR]

In this study, CO storage capacity in unmineable coalbeds in China at depths of 1,000-2,000 m has been evaluated using the methodology recommended by CSLF. This evaluation is one part of the countrywide CO storage capacity evaluations in China, initiated by the Chinese Ministry of Land and Resources. This level of CO storage capacity evaluation gives a rough scale of assessment with the least site-specific detail. The results show that there is a storage capacity of 98.81 × 10 t CO in coalbed s buried at a depth range of 1,000-2,000 m and 4.26 × 10 m additional coalbed methane can be recovered by CO injection. These results appear to show great potential and an attractive economic perspective of CO storage in unmineable coalbeds in China. Another part of this study is to classify the potential coalbed basins based on CO storage capacity and storage capacity per unit area. The study results reveal the distribution of the most potential basins for large-scale CO storage and the best economic basins for early CO storage in the future. [ABSTRACT FROM AUTHOR]

Carbon sequestration in shallow aquifers can be facilitated by water withdrawal. The factors that optimize the injection/withdrawal balance to minimize potential environmental impacts have been studied, including reservoir size, well pattern, injection rate, reservoir heterogeneity, anisotropy ratio, and permeability sequence. The effects of these factors on CO storage capacity and efficiency were studied using a compositional simulator Computer Modeling Group-General Equation of State Model, which modeled features including residual gas trapping, CO solubility, and mineralization reactions. Two terms, storage efficiency and CO relative breakthrough time, were introduced to better describe the problem. The simulation results show that simultaneous water withdrawal during CO injection greatly improves CO storage capacity and efficiency. A certain degree of heterogeneity or anisotropy benefits CO storage. A high injection rate favors storage capacity, but reduces the storage efficiency and CO breakthrough time, which in turn limits the total amount of CO injected. [ABSTRACT FROM AUTHOR]

Synfire chains, sequences of pools linked by feedforward connections, support the propagation of precisely timed spike sequences, or synfire waves. An important question remains, how synfire chains can efficiently be embedded in cortical architecture. We present a model of synfire chain embedding in a cortical scale recurrent network using conductance-based synapses, balanced chains, and variable transmission delays. The network attains substantially higher embedding capacities than previous spiking neuron models and allows all its connections to be used for embedding. The number of waves in the model is regulated by recurrent background noise. We computationally explore the embedding capacity limit, and use a mean field analysis to describe the equilibrium state. Simulations confirm the mean field analysis over broad ranges of pool sizes and connectivity levels; the number of pools embedded in the system trades off against the firing rate and the number of waves. An optimal inhibition level balances the conflicting requirements of stable synfire propagation and limited response to background noise. A simplified analysis shows that the present conductance-based synapses achieve higher contrast between the responses to synfire input and background noise compared to current-based synapses, while regulation of wave numbers is traced to the use of variable transmission delays. [ABSTRACT FROM AUTHOR]

We study the collective dynamics of a Leaky Integrate and Fire network in which precise relative phase relationship of spikes among neurons are stored, as attractors of the dynamics, and selectively replayed at different time scales. Using an STDP-based learning process, we store in the connectivity several phase-coded spike patterns, and we find that, depending on the excitability of the network, different working regimes are possible, with transient or persistent replay activity induced by a brief signal. We introduce an order parameter to evaluate the similarity between stored and recalled phase-coded pattern, and measure the storage capacity. Modulation of spiking thresholds during replay changes the frequency of the collective oscillation or the number of spikes per cycle, keeping preserved the phases relationship. This allows a coding scheme in which phase, rate and frequency are dissociable. Robustness with respect to noise and heterogeneity of neurons parameters is studied, showing that, since dynamics is a retrieval process, neurons preserve stable precise phase relationship among units, keeping a unique frequency of oscillation, even in noisy conditions and with heterogeneity of internal parameters of the units. [ABSTRACT FROM AUTHOR]

A regional scale, showcase saline aquifer CO storage model from the North German Basin is presented, predicting the regional pressure impact of a small industrial scale CO storage operation on its surroundings. The intention of the model is to bridge the gap between generic and site-specific, studying the role of fluid flow boundary conditions and petrophysical parameters typically found in the North German Basin. The numerical simulation has been carried out using two different numerical simulators, whose results matched well. The most important system parameters proved to be the model's hydrological boundary conditions, rock compressibility, and permeability. In open boundary aquifers, injection-induced overpressures dissipate back to hydrostatic level within a few years. If a geological flow barrier is present on at least one side of the aquifer, pressure dissipation is seriously retarded. In fully closed compartments, overpressures can never fully dissipate, but equilibrate to a compartment-wide remnant overpressure. At greater distances to the injection well, maximum fluid pressures are in the range of a few bar only, and reached several years to decades after the end of the actual injection period. This is important in terms of long-term safety and monitoring considerations. Regional pressure increase impacts the storage capacities of neighbouring sites within hydraulically connected units. It can be concluded that storage capacities may be seriously over- or underestimated when the focus is on a single individual storage site. It is thus necessary to assess the joint storage capacities and pressure limitations of potential sites within the same hydraulic unit. [ABSTRACT FROM AUTHOR]

Sodium lauryl sulphate (SLS) was used as a surfactant, thymol blue as a photosensitizer and mannose as a reductant in a photogalvanic cell to improve the conversion efficiency and storage capacity of such cells to achieve commercial viability. The photopotential and photocurrent generated were 635.0 mV and 100.0 μA, respectively. The effect of various parameters including concentration of photosensitizer, reductant and surfactant, pH and diffusion length on the cell properties was observed. The observed conversion efficiency and the maximum power of the cell were 0.23% and 24.60 μW, respectively. The fill factor was 0.25 at the power point of the cell. The photogalvanic cell can be used for 37 minutes in the dark following illumination for 120 minutes. The current-voltage characteristics of the photogalvanic cell were studied experimentally. All of the results observed for the system were lower in absence of surfactant. The absorption spectra of the systems with and without surfactant were also studied. [ABSTRACT FROM AUTHOR]

Significant attention has been given to the improvement of environmental flows in recent years. An important factor to reduce the opportunity cost of flood creation needed for the environment is the access to storage capacity. Reallocating storage capacity from agriculture to environment, however, may have important impacts on irrigation water prices and the vitality of irrigation enterprises. In this paper, the long term impacts of storage capacity reallocation on the agricultural sector are analysed. It is shown that a reduction in storage capacity for irrigation water will reduce water prices for each level of dam content and shift the distribution of dam content to the left. As a result, the value of the irrigation sector is reduced. The impact on average water price is, however, indeterminate, implying that results from previous empirical studies may be valid only locally and that sensitivity analysis is important to show the robustness of empirical results. [ABSTRACT FROM AUTHOR]

This paper contains brief description of ensemble neuron networks and some results of storage capacity estimation. Storage capacity shows how many ensembles can be stored in the neuron network of given size (given number of neurons in the network). It is shown that the number of ensembles can be much larger than the number of neurons in the network. We propose to apply this ensemble neural network to the problem of selection of adequate maneuver for robot-manipulator. At the input of the ensemble neural network we have the image of situation presented by the web-camera, and the output of the network will present us appropriate maneuver. The ensemble neural network is a good formalism for different maneuver representations. We propose to use ensemble neuron networks for this purpose. [ABSTRACT FROM AUTHOR]