Heat-injection production is a common technique for gas-hydrate development, and the mechanism needs further in-depth study, particularly of the decomposition characteristics of natural-gas hydrate, which are important fundamental issues. The natural gas-hydrate-reservoir model is based on a mathematical description of reservoir properties that considers the effects of hydrate decomposition and reservoir stress conditions. The aim of our investigation was to analyze the production and decomposition characteristics of natural-gas hydrates based on the results of numerical simulations of heat-injection production. The effects of different heat-injection temperatures and heat-injection rates on production were compared, and the decomposition characteristics of hydrates were evaluated qualitatively and characterized quantitatively by temperature distribution, saturation distribution, and the decomposition front in the process of heat-injection production of natural-gas hydrate. The results... [more]

, popularly known as mistletoe, is a semi-parasitic plant that can grow on many host plants and is native to Southeast Asia, especially Malaysia. D. pentandra is regarded as an unfavourable plant for an economically significant horticultural plant; however, D. pentandra is also regarded as a medicinal plant and is used in traditional and alternative medicine to treat coughs, diabetes, hypertension, and cancer. Scientific research has also found that this plant has significant potential for medical properties such as antioxidant, antibacterial, anticancer, antiproliferative, antidiabetic and antihyperglycaemic, anti-inflammatory, cytotoxicity, hepatoprotective, immunomodulatory, and anti-aging properties. Numerous phytochemical compounds from D. pentandra extracts have been identified using extraction techniques such as maceration and reflux. Thus, this review aims to provide thorough information on phytomorphology, extraction techniques, phytochemicals, biological activities, and the f... [more]

Parallel flow double and triple-effect vapor absorption cooling systems (VACS) are trying to meet the challenges of vapor compression cooling systems due to their better performance. Therefore, the present study deals with the review, thermodynamic analysis, and optimization of operating parameters for both double and triple-effect VACS. Lithium bromide water was selected as the working fluid, while liquified petroleum gas (LPG) and compressed natural gas (CNG) were taken as the source of energy to drive both the VACS. Detailed First Law analysis, i.e., coefficient of performance (COP), was examined along with the optimization of operating parameters (such as salt concentration and operating generators temperature at different pressure levels) and the volume flow rate of the gases. Optimization was carried out for maximum COP of the VACS using an iterative technique. Our results show that the COP of the triple-effect system was approximately 32% higher than the double effect, while 15−... [more]

Due to variables like wellbore deviation variation and flow rate, the local flow velocity in the output wellbore of horizontal shale oil wells varied significantly at various points in the wellbore cross-section, making it challenging to calculate the total single-layer production with accuracy. The oil−water two-phase flow rate calculation techniques for horizontal wells developed based on particular flow patterns and array spinners had excellent applicability in their respective niches but suffered from poor generalizability and demanding experience levels for logging interpreters. In this study, we employed five spinners in a triangular walled array instrument to create the multi-decision tree after figuring out how many leaf nodes there were and examining the defining characteristics of the observed values gathered under various experimental setups. The construction of the entire oil−water two-phase flow prediction model was made possible when the random forest regression approach... [more]

Due to their high energy density, long calendar life, and environmental protection, lithium-ion batteries have found widespread use in a variety of areas of human life, including portable electronic devices, electric vehicles, and electric ships, among others. However, there are safety issues with lithium-ion batteries themselves that must be emphasized. The safety of lithium-ion batteries is receiving increasing amounts of attention as incidents such as fires and explosions caused by thermal runaway have caused significant property damage and fatalities. Thermal runaway can easily occur when lithium-ion batteries experience issues such as electrical abuse and thermal abuse. This study compares various monitoring, warning, and protection techniques, summarizes the current safety warning techniques for thermal runaway of lithium-ion batteries, and combines the knowledge related to thermal runaway. It also analyzes and forecasts the future trends of battery thermal runaway monitoring, wa... [more]

α−Mangostin, which is a natural xanthone compound, inhibits the metastasis and survival of various cancer cell types. However, its therapeutic effectiveness is limited by low water solubility and very poor absorption. There are several studies that developed the drug delivery system for α−mangostin, but they are still a remaining challenge. Drug delivery techniques are severely hampered by the breakdown of nanoparticles inside endosomes. The abrasive chemical environment in these compartments causes both the nanoparticles and the encapsulated α−mangostin to degrade throughout the course of the voyage. Intracellular defenses against external materials refer to this collective mechanism. A pH-responsive liposome named PAsp(DET-Cit)−Toc, made of lipids and a charge-conversion polymer (CCP), has been created for the targeted transport of α−mangostin in order to avoid this deteriorative outcome. The average hydrodynamic size of CCP−liposome particles is 98.59 ± 5.1 nm with a PDI of 0.098 ±... [more]

Continuous dissolution of spent fuel is indeed one of the key technologies that can significantly improve the efficiency and stability of spent fuel reprocessing. The China Institute of Atomic Energy designed a prototype rotary drum dissolver, and the dissolution behavior of UO2 pellets in the dissolver was calculated using the Discrete Element Method. A kinetic equation was established to model the dissolution behavior, considering variables such as temperature, nitric acid concentration, and stirring intensity. The calculations showed that complete pellet dissolution took about 10 h in the continuous reaction, compared to 6 h in the batch dissolution experiment due to the gradual decrease in nitric acid concentration. A 16 h continuous dissolution experiment confirmed the calculated results, with a deviation of 10.8% between the simulation and experiment in terms of the mass of dissolved pellets. It was also found that it takes approximately 30 h to reach equilibrium in the continuou... [more]

(1) Background: The discharged temperature of steel slag is up to 1450 °C, representing heat having a high calorific value. (2) Motivation: A novel technology, integrating bio-oil steam reforming with waste heat recovery from steel slag for hydrogen production, is proposed, and it is demonstrated to be an outstanding method via thermodynamic calculation. (3) Methods: The equilibrium productions of bio-oil steam reforming in steel slag under different temperatures and S/C ratios (the mole ratio of steam to carbon) are obtained by the method of minimizing the Gibbs free energy using HSC 6.0. (4) Conclusions: The hydrogen yield increases first and then decreases with the increasing temperature, but it increases with the increasing S/C. Considering equilibrium calculation and actual application, the optimal temperature and S/C are 706 °C and 6, respectively. The hydrogen yield and hydrogen component are 109.13 mol/kg and 70.21%, respectively, and the carbon yield is only 0.08 mol/kg under... [more]

To promote the efficiency of waste heat recovery from granulated blast furnace (BF) slag, a novel method of catalyst-enhanced steam reforming of bio-oil to recover heat from slag is proposed. CaO is utilized as a superior catalyst for the process of catalyst-enhanced steam reforming. The thermodynamic production of the catalyst-enhanced steam reforming of bio-oil in granulated BF slag is obtained using HSC 6.0 software. The optimal conditions are mainly assessed according to the hydrogen yield, hydrogen concentration and carbon production. Through the thermodynamic production and industrial application, the temperature of 608 °C, S/C of eight and pressure of 1 bar are found as the optimal conditions. At the optimal conditions, the hydrogen yield, hydrogen concentration and carbon production are 95.25%, 76.89% and 0.28 mol/kg, respectively. Taking the temperature of 625 °C, S/C of eight and pressure of 1 bar as an example, the catalyst could improve the hydrogen yield and hydrogen conce... [more]

A breakthrough has been made in the recent exploration of the deep oil and gas bearing system in the eastern belt around the Penyijingxi sag of the Junggar Basin. These reservoirs are characterized by mixed sources and multi-stage accumulation. However, this process has not been thoroughly investigated, limiting our understanding of the fundamental rules of hydrocarbon migration and accumulation and making it difficult to determine exploration plans. This study mainly reconstructs this process using biomarkers, carbon isotopes, light hydrocarbons, and fluid inclusions. According to the biomarkers and carbon isotopes for oil-source correlation, Permian crude oil is a mixed-source oil from the Fengcheng Formation (P1f) and the Xiawuerhe Formation (P2w) source rocks, while Jurassic crude oil originates from the P2w source rock. The carbon isotope and light hydrocarbon data demonstrate that Jurassic natural gas has a mixed-gas characteristic with a preponderance of coal-type gas, in contra... [more]

Shale gas is mostly produced using horizontal wells, since shale gas reservoirs have low porosity and permeability. It is challenging to predict a horizontal well’s critical liquid-carrying gas flow rate because horizontal wells have more complicated well structures and gas−liquid two-phase pipe flows than vertical wells. In addition, there are significant differences between shale gas reservoirs and conventional natural gas reservoirs as well as dynamic changes in the liquid production rate. The majority of critical liquid-carrying models currently in use in engineering are based on the force analysis of droplets in the gas stream or liquid film on the pipe wall in annular-mist flow in the vertical wellbore. However, they do not take into account the impact of changes to the entire wellbore structure and dynamic changes in the liquid production rate on gas−liquid two-phase flow patterns and liquid carrying in the wellbore. In order to perform the critical gas velocity test for liquid... [more]

In order to ascertain the spatial and temporal changes in the air quality in Temuco City, Chile, we created and installed a network of inexpensive sensors to detect PM2.5 particulate matter. The 21 measurement points deployed were based on a low-cost Sensiron SPS30 sensor, complemented with temperature and humidity sensors, an Esp32 microcontroller card with LoRa and WiFi wireless communication interface, and a solar charging unit. The units were calibrated using an airtight combustion chamber with a Grimm 11-E as a reference unit. The calibration procedure fits the parameters of a calibration model to map the raw low-cost particle-material measurements into reliable calibrated values. The measurements showed that the concentrations of fine particulate material recorded in Temuco present a high temporal and spatial variability. In critical contamination episodes, pollution reaches values as high as 354 µg/m3, and at the same time, it reaches 50 µg/m3 in other parts of the city. The con... [more]

The use of dietary supplements (DSs) has dramatically increased in recent decades. However, around 20% of these products are reported to contain pharmacologically active undeclared compounds, most of which could expose consumers to serious side effects. According to recent data, some of the most commonly detected undeclared compounds are also considered doping and are prohibited by the World Anti-Doping Agency (WADA). One of the most frequently detected undeclared substances in DSs used for promoting weight loss is sibutramine. In 2011, all medicines containing sibutramine were urgently withdrawn from Europe and US markets because of serious side effects. In the present study, in order to detect and quantify sibutramine in DSs, a rapid, sensitive, and reliable gas chromatography with mass spectrometry (GC-MS) method was developed. The method was validated according to the ICH guidelines and demonstrated good linearity, accuracy, precision, and robustness. The limits of detection and qu... [more]

Understanding the importance of extraction optimization processes of bioactive molecules in the food industry is fundamental in the choice of innovative extraction processes involving sustainable procedures and is essential in process design for the isolation of antioxidants, thus preserving their chemical integrity and biological properties [...]

Global warming has had a profound impact on human life, with animal husbandry being a significant contributor to greenhouse gas emissions and playing a crucial role in the global greenhouse gas budget. Inner Mongolia is a major contributor to these emissions, making it vital to study the link between greenhouse gas emissions and animal husbandry in this region for the purpose of reducing emissions. In this study, the emissions of greenhouse gases (CH4, N2O, and CO2) from livestock and poultry breeding from 2010 to 2020 and the emissions of each city from 2020 were estimated, the emissions characteristics were analysed, and the low carbon emissions reduction technical measures were proposed. The results show that (1) the overall greenhouse gas emissions from 2010 to 2020 in Inner Mongolia showed a fluctuating trend; the main emissions sources were gastrointestinal fermentation and faecal management. The annual average CH4 emissions were 994,400 ta−1, and the annual average N2O emissions... [more]

In order to reduce the production cost of the methane carbon dioxide reforming reaction, and improve its actual production efficiency, in this paper, the optimal working parameters of the methane carbon dioxide reforming reaction are studied. The influence of different factors on methane conversion is studied via a single-factor numerical simulation analysis and the response surface methodology. Firstly, a numerical model of the methane carbon dioxide reforming reaction is established using Ansys Chemkin Pro software to analyze the influence of single factors (reactor temperature, reaction pressure, gas velocity) on methane conversion rate; secondly, the response surface model with the methane conversion rate as the response value is established using the BBD (Box−Behnken design) method; and finally, the order of influence of each variable on methane conversion and the optimal reaction conditions are determined using the response surface method. The factors are listed in order of their... [more]

As oil spills cause harm to the survival and environment of the ocean, the objective of the present paper is to study the oil migration range using the key indicator kv, which is defined as the ratio of oil spill speed to ocean current speed. The correctness of diffusion models created and estimated for subsea oil spills can be verified by experiments. We also considered the effect of key indicators on the horizontal and vertical dispersion ranges of oil spills. The study’s findings show that, under various kv settings, the horizontal and vertical spreading heights of oil spills both increase as kv rises. When kv is equal, the leakage velocity and water flow velocity increase synchronously, and over time, the horizontal distance and vertical diffusion height of the oil spill gradually increase. In the early stages of an oil spill, when kv = 50, 100, or 150, the vertical spreading velocity will rapidly decrease. The vertical spreading speed of spilled oil increases as kv rises when the... [more]

Lithium-ion batteries are widely utilized in various fields, including aerospace, new energy vehicles, energy storage systems, medical equipment, and security equipment, due to their high energy density, extended lifespan, and lightweight design. Precisely predicting the remaining useful life (RUL) of lithium batteries is crucial for ensuring the safe use of a device. In order to solve the problems of unstable prediction accuracy and difficultly modeling lithium-ion battery RUL with previous methods, this paper combines a channel attention (CA) mechanism and long short-term memory networks (LSTM) to propose a new hybrid CA-LSTM lithium-ion battery RUL prediction model. By incorporating a CA mechanism, the utilization of local features in situations where data are limited can be improved. Additionally, the CA mechanism can effectively mitigate the impact of battery capacity rebound on the model during lithium-ion battery charging and discharging cycles. In order to ensure the full valid... [more]

In response to the large-scale instability failure problem of designing coal pillars and support systems for gob-side entry driving (GSED) in high-stress soft coal seams in deep mines, the main difficulties in the surrounding rock control of GSED were analyzed. The relationship between the position of the main roof breaking line, together with the width of the limit equilibrium zone and a reasonable size for the coal pillar, were quantified through theoretical calculations. The theoretical calculations showed that the maximum and minimum widths of the coal pillar are 8.40 m and 5.47 m, respectively. A numerical simulation was used to study the distribution characteristics and evolution laws of deviatoric stress and plastic failure fields in the GSED surrounding rock under different coal pillar sizes. Theoretical analysis, numerical simulation, and engineering practice were comprehensively applied to determine a reasonable size for narrow coal pillars for GSED in deep soft coal seams, w... [more]

To date, biochar bacteriostatic material has attracted much attention from researchers. The compact porous structure of fish-scale biochar provides good application prospects. In this study, silver-carrying biochar−polyvinyl alcohol−alginate gel beads (C/PVA/SA) were designed for suppressing bacteria. The biochar was loaded with nano silver particles as the filler, alginate as the substrate, and polyvinyl alcohol (PVA) as the additive to enhance the mechanical properties. The composite gel beads were characterized using Fourier-transform infrared spectrometry (FT-IR). The results indicated that adjusting the PVA concentration could retain the bacteriostatic performance of the gel beads in different pH value solutions. It was found that C/PVA/SA gel beads had a strong inhibitory effect on Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. After ten consecutive antibacterial tests, the antibacterial rate remained high (above 99%) for 15 days. The adhesive effect of SA a... [more]

Multi-terminal DC transmission (MTDC) systems have attracted much attention due to their significant advantages in long-distance and high-capacity transmission. To improve their reliability and operation performance, a distributed fixed-time secondary control of frequency restoration and active power sharing is proposed under event-triggered communication, which only depends on the states of each AC grid and its neighbors. By utilizing Lyapunov theory, we prove that the MTDC system with the fixed-time secondary control can be stable in a settling time, and the conditions of the settling time are established for fixed-time algorithms. In addition, we simulate a five-terminal MTDC system in Matlab/Simulink. Several cases of MTDC systems are exhibited to showcase how well the suggested controller works when dealing with load changes and attacks. The comparison of the number of event-triggered instants shows that the proposed control method can effectively reduce communication resources.

Due to their unusual textural properties and semblance, gel foods have been welcomed by consumers. In this study, we designed a novel gel food, that is, broth jellies that enclosed particular food dices (shrimp, chicken, and potatoes). Briefly, various ratios of gelling molecules (gelatin and κ-carrageenan) were added to chicken broth, the food dices were placed in the center of the gels, and their characteristics and stabilities were verified during cold storage (4 °C) for 14 days. As a result, the mix of κ-carrageenan and gelatin led to the formation of firm cross-junctions with an elevated hardness compared to gelatin singular gel. In contrast, the gelatin sole gel showed different sensory attributes, such as a high chewiness and meltiness. The thick gel barriers of the products fairly increased the stability of the inner food ingredients. By blocking the loss of moisture, the texture and sensory traits were well preserved; moreover, the gelling molecules greatly impeded microbial d... [more]

The refractive index is an important physical property that is used to estimate the structural characteristics, thermodynamic, and transport properties of petroleum fluids, and to determine the onset of asphaltene flocculation. Unfortunately, the refractive index of opaque petroleum fluids cannot be measured unless special experimental techniques or dilution is used. For that reason, empirical correlations, and metaheuristic models were developed to predict the refractive index of petroleum fluids based on density, boiling point, and SARA fraction composition. The capability of these methods to accurately predict refractive index is discussed in this research with the aim of contrasting the empirical correlations with the artificial neural network modelling approach. Three data sets consisting of specific gravity and boiling point of 254 petroleum fractions, individual hydrocarbons, and hetero-compounds (Set 1); specific gravity and molecular weight of 136 crude oils (Set 2); and speci... [more]

A modified thermal Bhatnagar−Gross−Krook Lattice Boltzmann (BGK-LB) model was developed to study the convection phenomenon of non-Newtonian fluids (NNFs). This model integrates the local shear rate into the equilibrium distribution function (EDF) of the flow field and keeps the relaxation time from varying with fluid viscosity by introducing an additional parameter. In addition, a modified temperature EDF was constructed for the evolution equation of the temperature field to ensure the precise recovery of the convection−diffusion equation. To validate the accuracy and effectiveness of the proposed model, numerical simulations of benchmark problems were performed. Subsequently, we investigated the natural convection of power−law (PL) fluids and examined the impact of the PL index (n = 0.7−1.3) and Rayleigh number (Ra = 103−5 × 105) on the flow and temperature fields while holding the Prandtl number (Pr = 7) constant. The obtained results indicate that, for a given value of n, the convec... [more]

In the flexible manufacturing system deadlock prevention domain, researchers’ almost final target is to seek the maximally permissive controllers for solving the deadlock problems of flexible manufacturing systems. However, it seems a challenging work. Whatever you adopt, what kinds of methods, policies, and strategies, it seems complicated to obtain optimal controllers for deadlock prevention even if they claim their algorithms are optimal until the deadlock recovery is developed. Therefore, many experts, including us, have decided to design all kinds of actual maximally permissive recovery policies based on control transitions. It is a pity that these policies usually solve some particular flexible manufacturing systems’ deadlock problems. The controllers failed to recover the deadlock situation of flexible manufacturing systems once the idle or resource places were changed. In other words, these policies could never know or identify the real number of maximally permissive controller... [more]