Storage Capacity Research Articles

Exploring hydrogen adsorption and release in 2D M2C-MXenes: structural and functional insights.

Two-dimensional M2C-MXenes, characterized by their lightweight nature, tunable surface structures, and strong affinity for hydrogen, hold significant promise for addressing various challenges in hydrogen energy utilization. This study focuses on investigating the hydrogen adsorption and desorption properties, as well as the stability of hydrogenated compounds in 19 pure M2C-MXenes nanosheets. The results indicate that hydrogen adsorption on M2C primarily occurs through weak physisorption, with Mn2C and Fe2C from the fourth period, and Ag2C and Cd2C from the fifth period exhibiting the lowest adsorption energies. In contrast, hydrogen atoms are adsorbed on M2C primarily through chemisorption, leading to the potential dissociation of H2molecules into two hydrogen atoms. Among the M2C-MXenes, Ti2C, and Zr2C in thed4andd5, respectively, demonstrate the most stable hydrogen atom binding. Hydrogen evolution is most facile on Cu2C and Ag2C surfaces. Two types of stacking configurations, face-centered cubic and hexagonal close-packed, are observed for hydrogenated M2C surfaces (e.g. Co2C and Zr2C), showing excellent thermodynamic stability. This work elucidates the hydrogen utilization performance of pure M2C-MXenes nanosheets and guides future research aimed at achieving high hydrogen storage capacities through the functional tuning of MXenes.

Impact of boundary layer stability on urban park cooling effect intensity

Abstract. The added heat in cities amplifies the health risks of heat waves. At night under calm winds and cloud-free skies, the air in the urban canopy layer can be several degrees warmer than in rural areas. This lower nocturnal cooling in the built-up settings poses severe health risks to the urban inhabitants, as indoor spaces cannot be ventilated effectively. With heat waves becoming more frequent and more intense in future climates, many cities are expanding their green spaces with the aim to introduce cooling through shading, evaporation and lower heat storage capacities. In this study, we assessed how the evening and nighttime cooling effect of urban parks (relative to nearby built-up settings) varies with the park size and the mesoscale atmospheric conditions during warm summer periods. Using a combination of meteorological surface station data and compact radiosondes, the cooling effect is quantified for several urban parks (about 15 ha) and urban woods (about 900 ha). A profiling Doppler wind lidar deployed in the city centre is used to measure turbulent vertical mixing conditions in the urban boundary layer. We find that the maximum nocturnal cooling effects in urban parks range around 1–5 °C during a 1-week heat wave event in mid-July 2022 but also in general during summer 2022 (June–August). Three atmospheric stability and mixing regimes are identified that explain the night-to-night variability in the park cooling effect. We find that very low turbulent vertical mixing in the urban boundary layer (<0.05 m2 s−2) results in the strongest evening cooling in both rural settings and urban parks and the weakest cooling in the built-up environment. This regime specifically occurs during heat waves in connection with large-scale advection of hot air over the region and corresponding subsidence. When nocturnal turbulent vertical mixing above the city is stronger, the evening cooling in urban green spaces is less efficient, so the atmospheric stratification above both urban parks and woods is less stable, and temperature contrasts compared to the built-up environment are less pronounced. These results highlight the fact that urban green spaces have a significant cooling potential during heat waves, with maximum effects at night as advection and mixing transport processes are minimal. This suggests adapting the opening hours of public parks to enable residents to benefit from these cooling islands.

Optimal Harvest Maturity Changes Depending on the Season Throughout the Year in Papaya Grown in Mediterranean Climate-Improved Greenhouses

Papaya is a tropical fruit that is highly appreciated worldwide for its organoleptic properties and its nutritional and medicinal value. The optimal fruit quality for market requirements is determined by genotype, environmental conditions, and crop management, as well as fruit handling at harvest and adequate postharvest conservation. The aim of this work was to determine the optimal maturity stage, based on skin color, at which to harvest papayas grown in Mediterranean greenhouses with active climate control in south-east Spain, depending on the harvest season. We confirm that it is possible to produce high-quality papayas in our conditions, but the optimal harvest maturity stage in each season, along with the postharvest storage capacity, vary throughout the year, even with active climate control. Thus, 10% yellow skin color (S0) is the optimal for harvesting in autumn, mainly due to its better conservation capacity and firmness, having a high TSS content (>11 °Brix). In summer and spring, the lower TSS content discourages harvesting at S0, with S1 (30–40% yellow skin color) or S2 (50–60% yellow skin color) being the optimal stages for harvest to ensure the minimum TSS content required for papaya commercialization (10 °Brix). In any case, papayas produced under our conditions are generally well rated by consumers.

Minimization of Construction and Operation Costs of the Fuel Cell Bus Transportation System

This paper took the actual bus transportation system as the object, simulated the operating state of the system, replaced all the current diesel engine buses with fuel cell buses using electrolysis-produced hydrogen, and completed the existing timetable and routes. In the study, the numbers of hydrogen production stations and hydrogen storage stations, the maximum hydrogen storage capacity of the buses, the supplementary hydrogen capacity of the buses, and the hydrogen production capacity of the hydrogen storage stations were used as the optimal adjustment parameters for minimizing the ten-year construction and operating costs of the fuel cell bus transportation system by the artificial bee colony algorithm. Two hydrogen supply methods, decentralized and centralized hydrogen production, were analyzed. This paper used the actual bus timetable to simulate the operation of the buses, including 14 transfer stations and 112 routes. The results showed that the use of centralized hydrogen production and partitioned hydrogen production transfer stations could indeed reduce the construction and operating costs of the fuel cell bus transportation system. Compared with the decentralized hydrogen production case, the construction and operating costs could be reduced by 6.9%, 12.3%, and 14.5% with one, two, and three zones for centralized hydrogen production, respectively.

Green Hydrogen Blending into the Tunisian Natural Gas Distributing System

It is likely that blending hydrogen into natural gas grids could contribute to economy-wide decarbonization while retaining some of the benefits that natural gas networks offer energy systems. Hydrogen injection into existing natural gas infrastructure is recognised as a key solution for energy storage during periods of low electricity demand or high variable renewable energy penetration. In this scenario, natural gas networks provide an energy vector parallel to the electricity grid, offering additional energy transmission capacity and inherent storage capabilities. By incorporating green hydrogen into the NG network, it becomes feasible to (i) address the current energy crisis, (ii) reduce the carbon intensity of the gas grid, and (iii) promote sector coupling through the utilisation of various renewable energy sources. This study gives an overview of various interchangeability indicators and investigates the permissible ratios for hydrogen blending with two types of natural gas distributed in Tunisia (ANG and MNG). Additionally, it examines the impact of hydrogen injection on energy content variation and various combustion parameters. It is confirmed by the data that ANG and MNG can withstand a maximum hydrogen blend of up to 20%. The article’s conclusion emphasises the significance of evaluating infrastructure and safety standards related to Tunisia’s natural gas network and suggests more experimental testing of the findings. This research marks a critical step towards unlocking the potential of green hydrogen in Tunisia.

Numerical computations on thermal performance of large-scale Ti-Mn-based metal hydride storage reactor via open source CFD software

Certain metals and metal alloys can absorb hydrogen through an exothermic chemical reaction, resulting in the formation of metal hydrides. To maintain a rapid charging rate, the produced heat must be extracted as rapidly as it is generated. This study was attempted to evaluate the heat transfer enhancement in a cylindrical hydrogen storage reactor equipped with a central tube for large-scale applications using a 3D transient model. Finite-volume simulations are carried out using the open-source software package OpenFOAM to systematically investigate the impacts of material thermophysical properties, cooling media, and heat exchanger design on the heat transfer behaviors and hydrogen storage rate. The reactor’s performance was evaluated in terms of temperature and total hydrogen mass history profiles, in addition to pressure drop. The findings indicated that the charging time was improved by roughly 86%, compared to the case without thermal enhancement to attain 90% hydrogen storage capacity. A diminished pressure drop was observed between the water-based Al2O3 nanofluid with 5 vol% concentration and pure water at lowered coolant flow velocities, hence enhancing pumping power efficiency. Moreover, the results demonstrated that the storage rate is markedly improved by enhancing the effective thermal conductivity of the hydride bed, increasing the heat exchange area, accelerating the coolant flow rate, and lowering its temperature. The outcomes highlighted the possibility of advancing the current metal hydride reactor for practical application.

Decreased Adipose Lipid Turnover Associates With Cardiometabolic Risk and the Metabolic Syndrome.

Disturbed white adipose tissue function is important for cardiometabolic risk and metabolic syndrome (MetS). Whether this involves adipose lipid turnover (lipolysis and synthesis of triglycerides) is unknown and was presently investigated in subcutaneous adipose tissue, the body's largest fat depot. In cross-sectional studies in 78 subjects, adipose lipid age, representing overall lipid turnover (mobilization and storage), and lipid storage capacity were assessed by the incorporation of atmospheric 14C into adipose lipids. Adipose lipid age from an algorithm of adipocyte lipolysis and clinical parameters was also determined in 185 subjects. Adult Treatment Panel III (ATPIII) scoring defined MetS (scores 3-5) or healthy (score 0). ANOVA or ANCOVA and t test were used for statistical comparison. Because there was no method interaction to determine lipid age, the 2 groups were combined. Lipid age increased by incremental ATPIII score (F=42; P<0.0001) and was 2-fold advanced in MetS (t=11.3; P<0.0001). The correlation with lipid age was independent of age, sex, body mass index, waist-to-hip ratio, sedentary lifestyle, absence of obesity, and adipose insulin resistance (F=10.7; P<0.0001). Lipid storage capacity was not related to the ATPIII score (F=1.0; P=0.44) or MetS (t=-0.9; P=0.35). Adipocyte lipolysis activation was decreased in MetS and inversely related to incremental ATPIII score, suggesting that decreased lipid mobilization is the major factor behind high lipid age in these conditions. Despite normal lipid assimilation capacity, abdominal subcutaneous adipose lipid turnover is decreased in MetS and high ATPIII score because of impaired ability to mobilize lipids involving low adipocyte lipolysis activation.

A COMPARATIVE STUDY OF QUADRUPOLE RAIL LAUNCHER AND TWO-WING ARMATURE ELECTROMAGNETIC LAUNCHER: MAGNETIC AND PERFORMANCE METRICS

This study presents a novel two-wing armature electromagnetic launcher design that aims to overcome the limitations of conventional quadrupole railguns. The proposed TWAEL system exhibits significantly enhanced magnetic field properties, achieving a 23-fold increase in magnetic flux density, an increase in magnetic field intensity, and a 1.6-fold increase in current density compared to the QRL under identical input conditions. Consequently, the TWAEL demonstrates a 6.7-fold greater electromagnetic co-energy storage capacity per unit volume, translating to substantially higher accelerative forces, reaching up to 18,045 N. Simulations validate the TWAEL's superior performance in terms of magnetic field characteristics and energy conversion efficiency, highlighting its potential as an advanced, high-performance electromagnetic propulsion system for various applications.

Latent Thermal Energy Storage for Cooling Demands in Battery Electric Vehicles: Development of a Dimensionless Model for the Identification of Effective Heat-Transferring Structures

Thermal energy storage (TES) systems open up alternative paths for air conditioning to increase the range of battery electric vehicles (BEVs) by reducing power consumption. The central prerequisites for this purpose are high storage densities: high-temperature TES systems are being focused on for heat demands, while effective solutions for cooling are missing. Due to their lower temperature potentials, concepts with high storage capacities and heat transports between the storage and cold transferring medium are needed. Latent TES systems based on water enable these capacities but require adequate internal structures for effective heat transfer. Due to the large number of geometric options, high simulation efforts must be conducted to identify favored structures, or the possible design space must be limited for investigations. For this purpose and for the first time, an alternative way is presented using newly developed dimensionless models in a top-down methodology for time-efficient design studies and evaluations. These models were successfully validated and used as a design tool to identify effective structures in latent TES systems for cooling demands in BEVs. A wide array of variation studies on tube, finned plate and novel Triply Periodic Minimal Surface (TPMS) structures were performed and uniformly evaluated with regard to storage densities, cooling efficiencies and geometry. The results show high storage densities for novel TPMS structures, including the enclosure of 100 Wh/kg or 102.2 kWh/m3 with average cooling capacities of 1 kW over 30 min, confirming the usability of latent TES systems in terms of compactness and efficiency for cooling demands in BEVs.

Effects of Peatland Fires on Above-ground Carbon Stocks in Kepulauan Meranti Regency, Riau Province

Peat fires substantially alter ecosystem dynamics and carbon storage, making it essential to understand how fire-related components affect post-fire carbon stocks. This study aims to estimate the above-ground carbon stock on burned peatlands in Kepulauan Meranti Regency, Riau Province, and examine how fire recurrence, last fire occurrence, and burn severity influence the carbon stock using a modified regression model and remote sensing data. The normalized burn ratio index difference between post- and pre-fire was used to calculate burn severity. The continuous predictor variable was transformed using a natural logarithm to generate the best-fit model. The 2014 burned peatland stored the highest carbon, whereas the 2020 burned peatland was the lowest. The 2020 fire period was the most severe compared to the 2014 and 2018–2019 fires, although it had a smaller burned area. This study highlights that fire-related components significantly affect post-fire peatland above-ground carbon stocks, particularly last fire occurrence and burn severity. Meanwhile, fire recurrence had the weakest impact and correlation with above-ground carbon stock compared to other predictors, likely due to the brief intervals between fire events in 2018 and 2019, which may have restricted ecosystem recovery and limited carbon storage capacity.

Design and Control of Radial Electromagnetic Bearing for Flywheel Battery

Abstract High rotational speed is the key to increasing energy storage capacity of flywheel battery. Non-contact bearing ensures reliable operation of high-speed flywheel battery. To design an electromagnetic bearing that meets the requirement of high-speed flywheel battery, firstly, a multi-parameters and multi-objectives optimization model for radial electromagnetic bearing is established. The optimization aims at the smallest spatial volume while ensuring electromagnetic force. A 16.58% reduction of the spatial volume is obtained. Furthermore, the influence of bias current and control current on the electromagnetic force and rotor displacement of radial magnetic bearing are analyzed. The bias current and control current that meet the requirements of current stiffness and displacement stiffness are determined. Based on this, a differential control model for radial magnetic bearing is constructed. Then, a controller based on adaptive discrete sliding mode control is designed. Finally, performance test and data analysis are completed. Results indicate that the designed radial electromagnetic bearing is able to achieve low response error, low system jitter and high robust under different test conditions. Compared with traditional sliding mode control method, under stochastic excitation, the maximum and average tracking errors of bearing displacement are reduced by 62.31% and 42.74%. The energy consumption is decreased by 49.32%.

Effects of Rock Water with Different Alkalinity and Pre-Oxidation on Re-Ignition Characteristics of Residual Coal

ABSTRACT To investigate the impact of alkaline rock water (pH = 8, 9) combined with pre-oxidation on changes in pore structure and functional groups of residual coal in goaf, and consequently, on the secondary oxidation and spontaneous combustion characteristics of coal samples, an analysis was conducted. This analysis focused on examining changes in pore morphology and functional group content of pre-oxidized coal (OI0) and water-immersed oxidized coal (OI) through experiments utilizing low-temperature nitrogen adsorption and in-situ diffuse reflectance infrared spectroscopy. Secondary oxidation and spontaneous combustion characteristics of coal samples were analyzed using thermogravimetric differential thermal analysis incorporating oxidation kinetic theory. The findings indicated that after the combined effect of pre-oxidation and alkali leaching, the mesopore volume of the coal decreased, pore complexity increased, oxygen storage capacity was enhanced, and the apparent activation energy of the coal samples was significantly reduced. This reduction in activation energy was pronounced at lower temperatures but less so at higher temperatures. Specifically, the methyl and methylene contents of OI9 were significantly higher than those of other coal samples within the temperature range of 80–160°C. Meanwhile, the heat release of the low-temperature oxidation stages of OI0, OI8, and OI9 increased by 70.82%, 190.25%, and 75.05%, respectively, compared with RC. The study indicates an elevated risk of spontaneous coal combustion following the combined treatment of alkaline leaching and pre-oxidation. This research elucidates the mechanism of spontaneous combustion of water-immersed coal by alkaline rock water and pre-oxidation, providing valuable insights for the control of coal fires in alkaline mine-water environments.

Coastal carbon storage in degraded, natural, and restored mangrove ecosystems of Guyana

Mangroves are among the most carbon-rich forests in the tropics due to their capacity to sequester and store carbon within their ecosystems. However, the combination of natural and human-induced phenomena causes changes in these ecosystems which can affect the flow of carbon within them. In the wet and dry seasons, we examined and compared the carbon content stored in aboveground biomass, standing litter, and soil in natural, degraded, and restored mangrove ecosystems located along the Guyana coastline. During a one-year period, a point-centred quartered method was used for tree sampling, while a randomised block design was used for standing litter and soil sampling. Our study revealed that the natural ecosystems exhibited higher carbon pool levels (29.58–35.14 Mg ha−1), followed by the degraded ecosystems (30.49–32.27 Mg ha−1), and then the restored ecosystems (22.81–27.63 Mg ha−1). Significant differences were documented only in carbon found in aboveground biomass between ecosystem states, particularly within the natural ecosystems, due to the presence of mature trees with larger diameters at breast height. While seasonal fluctuations exist between the various carbon pools, particularly within the degraded ecosystems, our findings yielded insignificant differences between seasonality for all three carbon pools. However, linear mixed-effect models revealed that seasonality may influence the soil and standing litter carbon concentrations to an extent. Positive correlations in the restored ecosystems suggest that the larger carbon stocks in aboveground biomass may be associated with carbon stocks in soil and standing litter, unlike the negative correlations seen in the natural and degraded ecosystems. Our study provides some evidence that the overall carbon storage capacity of mangroves is influenced by the current state of their ecosystem, that is, ecosystems characterised by minimum disturbances may possess a greater capacity for carbon storage in comparison to ecosystems that are currently experiencing or have recovered from disturbances.

Multiscale Qualitative–Quantitative Characterization of the Pore Structure in Coal-Bearing Reservoirs of the Yan’an Formation in the Longdong Area, Ordos Basin

Accurate characterization of coal reservoir micro- and nanopores is crucial in evaluating coalbed methane storage and gas production capacity. In this work, 12 coal-bearing rock samples from the Jurassic Yan’an Formation, Longdong area, Ordos Basin were taken as research objects, and micro- and nanopore structures were characterized via scanning electron microscopy, high-pressure mercury pressure, low-temperature N2 adsorption and low-pressure CO2 adsorption experiments. The main factors controlling coal pore structure development and the influence of pore development on the gas content were studied by combining the reflectivity of specular samples from the research area, the pore microscopic composition and the pore gas content determined through industrial analyses and isothermal absorption experiments. The results show that the coal strata of the Yan’an coal mine are a very important gas source, and that the coal strata of the Yan’an Formation in the study area exhibit remarkable organic and clay mineral pore development accompanied by clear microfractures and clay mineral interlayer joints, which together optimize the coal gas storage conditions and form efficient microseepage pathways for gas. Coalstone, carbonaceous mudstone and mudstone show differential distributions in pore volume and specific surface area. The general trend is that coal rock is the best, carbonaceous mudstone is the second best, and mudstone is the weakest. The coal samples’ microporous properties are positively correlated with the coal sample composition for the specular group, whereas there is no clear correlation for the inert group. An increase in the moisture content of the air-dried matrix promotes adsorption pore development, leading to increases in the microporous volume and specific surface area. CH4 adsorption in coal rock increases with increasing pressure, and the average maximum adsorption is approximately 8.13 m3/t. The limit of the amount of methane adsorbed by the coal samples, VL, is positively correlated with the pore volume and specific surface area, indicating that the larger the pore volume is, the greater the amount of gas that can be adsorbed by the coal samples, and the larger the specific surface area is, the greater the amount of methane that can be adsorbed by the coal samples. The PL value, pore volume and specific surface area are not correlated, indicating that there is no direct mathematical relationship between them.

A Body-Temperature-Triggered In Situ Softening Peripheral Nerve Electrode for Chronic Robust Neuromodulation.

Implantable peripheral nerve electrodes are crucial for monitoring health and alleviating symptoms of chronic diseases. Advanced compliant electrodes have been developed because of their biomechanical compatibility. However, these mechanically tissue-like electrodes suffer from unmanageable operating forces, leading to high risks of nerve injury and fragile electrode-tissue interfaces. Here, a peripheral nerve electrode is developed that simultaneously fulfills the criteria of body temperature softening and tissue-like modulus (less than 0.8MPa at 37°C) after implantation. The central core is altered from the tri-arm crosslinker to the star-branched monomer to kill two birds (close the translation temperature to 37°C and decrease the modulus after implantation) with one stone. Furthermore, the decreased interfacial impedance (325.1±46.9Ω at 1kHz) and increased charge storage capacity (111.2±5.8mCcm-2) are achieved by an in situ electrografted conductive polymer on the strain-insensitive conductive network of Au nanotubes. The electrodes are readily wrapped around nerves and applied for long-term stimulation in vivo with minimal inflammation. Neuromodulation experiments demonstrate their potential clinical utility, including vagus nerve stimulation in rats to suppress seizures and alleviation of cardiac remodeling in a canine model of myocardial infarction.

Structural Analysis of Variants of the Ferritin Light Chain Protein and Its Relationship with Neuroferritinopathy.

Ferritin is a highly conserved spherical protein that stores iron and possesses triple and quadruple symmetry input ports. Additionally, it is composed of light chains that can be affected by post-translational mutations, reducing the iron storage capacity in the brain and leading to neuroferritinopathy, which is a rare disease with limited bioinformatics data. In this study, we analyzed the biochemical mechanism of different ferritin mutations reported in the literature, through the characterization and determination of the in silico structural model by searching databases, implementing bioinformatics programs such as Jalview, NetNGlyc 1.0, NetOGlyc 3.1, and three-dimensional structure predictors with machine learning such as Alphafold, demonstrating the generation of hairpin and steric hindrances that hinder the aggregation of subunits and changes in the size and arrangement of quadruple and triple entry holes of the A96T mutation compared to the wild-type protein, since in the quadruple entry hole, a decrease in area is observed compared to the wild-type protein and the triple entry hole has a decrease in distance measurements of 6.504 Å. This possibly affects the functionality of the protein, thus releasing high concentrations of iron in the brain and causing neurodegeneration.

Research on Distributed Secure Storage Framework of Industrial Internet of Things Data Based on Blockchain

The conventional centralized Industrial Internet of Things (IIoT) framework is plagued by issues like subpar security performance and challenges related to storage expansion. This paper proposes a two-tier distributed secure storage framework based on blockchain for IIoT data. The authors first introduce the two-layer framework, which includes the edge network layer and the blockchain storage layer. The nodes in the edge network layer are classified into administrator nodes and ordinary nodes. It provides a lower latency network environment compared to cloud computing to preprocess raw industrial data. The blockchain storage layer provides storage space to keep data secure and traceable. Secondly, the authors propose a differentiated storage solution. Based on the timestamps of industrial data and the specific media access control (MAC) address, the Universally Unique Identifier (UUID) of the raw data is generated and uploaded to the blockchain for secure storage. Encrypt the corresponding raw data using the elliptic curve cryptography algorithm, and then upload it to InterPlanetary File System (IPFS) to expand the storage capacity of the blockchain. Deploy a smart contract on the blockchain to compare UUIDs for consistency in an automated, lightweight method to determine data integrity. Finally, we analyze the advantages brought by the integration of blockchain and IIoT. Additionally, the authors design comparative tests on different storage methods. The results prove that the security of this paper’s scheme is improved, and the storage performance is extended. Noteworthy enhancements include heightened throughput of data uploaded to the blockchain and minimized delay overhead.

Research on optimal scheduling of minor and moderate floods for cascade reservoirs in the lower reaches of the jinsha river considering power generation

The comprehensive cascade reservoir system is extensively used for flood control and power generation. Traditional reservoir scheduling often treats these tasks as competing objectives, prioritizing flood control during the flood season and neglecting power generation benefits. This approach, primarily applied to large floods, leads to hydraulic resource wastage and power generation loss during minor and moderate floods. The lower Jinsha River cascade reservoirs have significant flood control storage capacity, allowing part of the capacity to be used for maintaining higher water levels without compromising safety under minor and moderate floods within a 20-year return period. This paper proposes an optimal scheduling model that considers both flood control and power generation tasks for the lower Jinsha River cascade reservoirs. The Multi-objective Particle Swarm Optimization (MOPSO) algorithm was used to find non-inferior solution sets. An evaluation index system was developed to select optimal solutions under different flood frequencies, using the Minimum Discriminant Information Principle and VIKOR model. The results indicate that the optimal scheduling scheme under 20-year, 10-year, and 5-year return period floods can enhance power generation by 1.64, 1.71, and 1.35 billion kWh, respectively, compared to conventional scheduling. This approach supports coordinated flood control and power generation scheduling, contributing to the high-quality development of the Yangtze River Economic Belt.

Evaluation of reserves and injection-production capacity of underground gas storage under multi-cycle operation

In order to more accurately estimate the reserves of underground gas storage under the complex operation mode of multi-period strong injection and strong production, and design a reasonable allocation scheme of injection and production gas volume. In this paper, the material balance equation is improved according to the “hollow square” shape characteristics of apparent bottom hole flow pressure and cumulative production of multi-cycle injection-production wells in gas storage. Combined with the node analysis method, a new evaluation method of multi-period reserves and injection-production capacity of underground gas storage is established by using the vertical pipe flow equation, erosion flow equation, critical liquid carrying flow equation and critical sand flow equation to constrain the gas inflow and outflow equations respectively. Then, taking the gas storage as a case, the method is compared with the field data. The results show that this method avoids the inconsistency of the existing methods in solving the reserves of underground gas storage, and provides a more scientific and relatively reliable method for reserves and capacity prediction.

Fabrication and evaluation of Wrap Around Neural-Pass to record and stimulate neural activity in the cervical spinal cord

Abstract We have successfully fabricated a Wrap Around Recording Electrode to record neural activity in the Cervical Spinal Cord (CSC) and a Wrap Around Stimulating Electrode to stimulate the CSC. These are used in the Wrap Around Neural-Pass to improve the QOL of patients with CSC injury by restoring motor, sensory, upper limb, and lower limb nerves minimally invasively that invades only the CSC. The fabricated electrodes had sufficient wrapping ability to be wrapped around the CSC of rats and could record neural activity in the rat’s spinal cord. We also clarified the optimal polymerization conditions for PEDOT used as the stimulating electrode material for the Wrap Around Stimulating Electrode, and the electrodes had low impedance, high Cathodal Charge Storage Capacity (CSCC), and Charge Injection Capacity (CIC) suitable for stimulating the CSC nerves.