Browse
Record Types
Records with Type: Published Article
Showing records 1344 to 1368 of 43292. [First] Page: 1 51 52 53 54 55 56 57 58 59 Last
A Multimodal Fusion System for Object Identification in Point Clouds with Density and Coverage Differences
Daniel Fernando Quintero Bernal, John Kern, Claudio Urrea
June 7, 2024 (v1)
Keywords: density differences, LiDAR, multimodal fusion, object identification, point clouds, point coverage
Data fusion, which involves integrating information from multiple sources to achieve a specific objective, is an essential area of contemporary scientific research. This article presents a multimodal fusion system for object identification in point clouds in a controlled environment. Several stages were implemented, including downsampling and denoising techniques, to prepare the data before fusion. Two denoising approaches were tested and compared: one based on neighborhood technique and the other using a median filter for each “x”, “y”, and “z” coordinate of each point. The downsampling techniques included Random, Grid Average, and Nonuniform Grid Sample. To achieve precise alignment of sensor data in a common coordinate system, registration techniques such as Iterative Closest Point (ICP), Coherent Point Drift (CPD), and Normal Distribution Transform (NDT) were employed. Despite facing limitations, variations in density, and differences in coverage among the point clouds generated by... [more]
Parameter Calibration for Discrete Element Simulation of the Interaction between Loose Soil and Thrown Components after Ginseng Land Tillage
Ke Du, Jingli Wang, Min Liu, Pengyu Wang, Daping Fu, Weizhi Feng, Lidong Chu, Yichao Ning, Yang Wang, Yingjie Guo
June 7, 2024 (v1)
Keywords: contact model, DEM, discrete element method, ginseng soil, parameter selection
Given the lack of accurate and reliable discrete element simulation parameters to study the interactions between soft soil and soil casting components after ginseng land cultivation in Northeast China and the design of ginseng land-specific borders, this paper calibrates the relevant model parameters of ginseng soil using the Hertz−Mindlin with JKR contact model in EDEM to standardize the contact parameters between soil particles and between soil and Q235 steel in soft soil after cultivation in ginseng land. Taking the soil particle accumulation angle as the response value, a Box−Behnken design (BBD) was introduced to establish a regression model for the soil accumulation angle; the surface energy, static friction coefficient, rolling friction coefficient, and coefficient of restoration parameters were obtained, respectively, through the optimization of the model, at which time, the simulated value of the soil accumulation angle was 37°, which is a 4% relative error to the actual measu... [more]
The Influence of the Application Layer of Pouring Semi-Flexible Pavement Material on Low-Temperature Stress
Guoxun Li, Deyong Wang, Huaizhi Zhang, Biao Xu, Fan Yang, Zhen Zhang
June 7, 2024 (v1)
Subject: Materials
Keywords: application layer, low-temperature stress, pouring semi-flexible pavement material
Pouring semi-flexible pavement material (PSFM) is widely used as a wearing layer material or below pavement due to its excellent resistance to deformation at high temperatures and under heavy loads. However, in cold regions, the material exhibits severe cracking issues. The primary objective of this study is to enhance the resistance of pouring semi-flexible pavements (SFPs) to low-temperature cracking in cold regions by strategically designing pavement structures that incorporate PSFM. To achieve this goal, we conducted indoor tests to determine the relaxation modulus and temperature shrinkage coefficient of PSFM and simulated a pavement structure using COMSOL finite element simulation. The impacts of different application layers and layer thicknesses on low-temperature stresses were investigated based on these findings. The research findings indicate that when PSFM is used as the wearing layer material, the low-temperature stress is 4.7% lower than that of typical materials used in t... [more]
Rapid and Non-Destructive Determination of Fatty Acid Profile and Oil Content in Diverse Brassica carinata Germplasm Using Fourier-Transform Near-Infrared Spectroscopy
Misteru Tesfaye, Tileye Feyissa, Teklehaimanot Hailesilassie, Eu Sheng Wang, Selvaraju Kanagarajan, Li-Hua Zhu
June 7, 2024 (v1)
Subject: Materials
Keywords: B. carinata, fatty acid profile, FT-NIR spectroscopy, germplasm screening, oil content
is one of the oilseeds in the Brassicaceae family, possessing seed quality traits such as oil with various fatty acid profiles suitable for many industrial applications. Determination of such quality traits using conventional methods is often expensive, time-consuming, and destructive. In contrast, the Near-Infrared Spectroscopic (NIRS) technique has been proven fast, cost-effective, and non-destructive for the determination of seed compositions. This study aimed to demonstrate that NIRS is a rapid and non-destructive method for determining the fatty acid profile and oil content in diverse germplasms of B. carinata. A total of 96 genetically diverse B. carinata germplasms that include accessions, advanced breeding lines, and varieties were used in this study. Reference data sets were generated using gas chromatography and the Soxhlet oil extraction method for fatty acid profile and oil content, respectively. Spectra data were taken from the wavenumber range of 11,500 to 4000 cm−1 using... [more]
Environmental Protection through Aerobic Granular Sludge Process
Yong-Qiang Liu
June 7, 2024 (v1)
Subject: Environment
Aerobic granular sludge (AGS) represents a significant advancement in wastewater treatment technology [...]
Anti-Glioblastoma Potential and Phenolic Profile of Berry Juices
Mirela Kopjar, Drazen Raucher, Mary Ann Lila, Josip Šimunović
June 7, 2024 (v1)
Subject: Biosystems
Keywords: anthocyanins, antiproliferative potential, dwarf elderberry juice, raspberry juice, wild blackberry juice
Glioblastoma is one of the most aggressive and lethal brain tumors. Due to the failure of conventional chemotherapies and targeted drugs pursuit of natural, less toxic agents is on the rise as well as their utilization in glioblastoma treatment. Consequently, this study explores the antiproliferative potential of selected berry juices (wild blackberry (Rubus discolor), dwarf elderberry (Sambucus ebulus), and raspberry (Rubus idaeus)) on glioblastoma cells (U87-MG and GBM43) in comparison to temozolomide. The juices were assessed for total phenolic content, proanthocyanins, polyphenol profiles, and antioxidant activity. Wild blackberry and dwarf elderberry juices exhibited higher total polyphenols, proanthocyanins, and monomeric anthocyanins compared to raspberry juice. HPLC analysis revealed distinctive anthocyanins, flavonoids, and phenolic acids in each juice. With the DPPH assay, the highest antioxidant potential had wild blackberry juice, while with other assays dwarf elderberry ju... [more]
Preparation of High Specific Surface Area Activated Carbon from Petroleum Coke by KOH Activation in a Rotary Kiln
Kechao Wang, Shaoping Xu
June 7, 2024 (v1)
Subject: Materials
Keywords: activated carbon, activation, high specific surface area, KOH, Petroleum Coke, rotary kiln
In the preparation of high specific surface area activated carbon (AC) by KOH activation, the swelling of the reactant mixture and the particles’ agglomeration deteriorates the process and the property of product. In this study, a novel method using a rotary kiln loaded with steel balls has been developed for the preparation of AC from petroleum coke (PC) by KOH activation. It has been found that the molten KOH caused the swelling of the reaction mixture at a lower activation temperature, while the molten K2O led to the particles’ agglomeration at a higher temperature. The steel balls could relieve the swelling and agglomeration and enhance the pore structure development of the AC by boosting the heat and mass transfer in the reactor. At an activation temperature of 800 °C and a KOH/PC mass ratio of 3:1, the specific surface area of the AC obtained without the addition of steel balls in the kiln is 1492 m2/g, while that with the steel balls is 1996 m2/g. The introduction of CO2 during... [more]
Progress and Perspectives in the Development of Inorganic-Carbonate Dual-Phase Membrane for CO2 Separation
Liyin Fu, Xiaojie Shi, Huiling Wu, Yabin Ma, Xuechao Hu, Tianjia Chen
June 7, 2024 (v1)
Subject: Materials
Keywords: CO2 separation, high-temperature separation, inorganic membrane, membrane reactor
The inorganic-carbonate dual-phase membrane represents a class of dense membranes that are fabricated using diverse support materials, ranging from metals to ceramics. This dual-phase membrane consists of a porous metal or ceramic support with an introduced carbonate phase within the support pores. Compared with polymer and zeolite membranes, inorganic-carbonate dual-phase membranes exhibit exceptional CO2 selectivity at elevated temperatures (>500 °C), making them an ideal choice for high-temperature CO2 separation in power plant systems. The present paper provides a comprehensive overview of the separation principle, significant models, and preparation techniques employed in carbonate dual-phase membranes for CO2 separation. The present study aims to discuss key factors that limit the CO2 permeation performance and stability of membranes, while also exploring the potential applications of dual-phase membranes in various fields. The identification of key challenges in the future devel... [more]
Diagnostics of Secondary Fracture Properties Using Pressure Decline Data during the Post-Fracturing Soaking Process for Shale Gas Wells
Jianfa Wu, Liming Ren, Cheng Chang, Shuyao Sheng, Jian Zhu, Sha Liu, Weiyang Xie, Fei Wang
June 7, 2024 (v1)
Keywords: fracture diagnostics, secondary fracture, shale gas, soaking
In addition to main fractures, a large number of secondary fractures are formed after the volumetric fracturing of shale gas wells. The secondary fracture properties are so complex, that it is difficult to identify and diagnose by direct monitoring methods. In this study, a new approach to model and diagnose secondary fracture properties is presented. First, a new pressure decline model, which is composed of four interconnected domains, i.e., wellbore, main fractures, secondary fractures, and reservoir matrix pores, is built. Then, the fracturing fluid pumping and post-fracturing soaking processes are simulated. The simulated pressure derivatives reflect five fracture-dominated flow regimes, which correspond to multiple alternating positive and negative slopes of the pressure decline derivative. The results of sensitivity simulation show that the density, permeability, and width of secondary fractures are the main controlling factors affecting the size ratio. Finally, based on the simu... [more]
Correction: Radaš et al. A Method for Estimating the State of Charge and Identifying the Type of a Lithium-Ion Cell Based on the Transfer Function of the Cell. Processes 2024, 12, 404
Ivan Radaš, Luka Matić, Viktor Šunde, Željko Ban
June 7, 2024 (v1)
In Section 4 of the original publication [...]
Solid-State Fermentation of Hyperactive Pectinase by the Novel Strain Aspergillus sp. CM96
Huiling Chen, Meimei Wan, Yang Liu, Guanghua Yang, Zhiqiang Cai
June 7, 2024 (v1)
Keywords: Aspergillus sp., enzyme cocktail, hyperactive pectinase, nutrient digestibility, solid-state fermentation
Pectinase, a kind of hydrolase, mainly contains polygalacturonase, pectinase, and pectin lyase, which can hydrolyze pectin to generate galacturonide and is widely used in industry. At present, pectinase’s activity is still relatively low. Hyperactive pectinase was produced with solid-phase fermentation and a tray bioreactor using the novel strain Aspergillus sp. CM96 in this study. This pectinase’s activity can reach 17,000 U·g−1 after fermentation with a tray bioreactor, an increase of 86% compared to that obtained using flask liquid fermentation. The pectinase was purified and its characteristics were explored. Additionally, during pectinase fermentation, the activities of protease, glucanase, and cellulase were also determined to reach 7000, 8000, and 3000 U·g−1. The enzyme mixture was used to improve substrate digestion efficiency in 144 Soviet white pigs after adding a 0.05% cocktail enzyme for 38 days. The results showed that the average daily gain (ADG) increased by 139.41 ± 1.0... [more]
Study of Mid-Pressure Ar Radiofrequency Plasma Used in Plasma-Enhanced Atomic Layer Deposition of α-Al2O3
Carl-Thomas Piller, Jüri Raud, Lauri Aarik, Indrek Jõgi, Rasmus Talviste, Jaan Aarik
June 7, 2024 (v1)
Subject: Materials
Keywords: argon plasma, capacitively coupled plasma, optical emission spectroscopy, plasma-enhanced atomic layer deposition
This study investigated the characteristics of radiofrequency, middle-pressure argon plasma used in the atomic layer deposition (ALD) of Al2O3 films. Based on the electrical characteristics—the current, voltage, and phase shift between them—and the stability of the plasma plume, the optimum plasma power, allowing reliable switching on of the plasma for any step of an ALD cycle, was determined. Spectral measurements were performed to determine the gas temperature and reactive species that could be important in the ALD process. The density of metastable argon atoms was estimated using tunable laser absorption spectroscopy. It was concluded that plasma heating of substrates did not affect film growth. The crystallization-enhancing effect of plasma observed in these experiments was due to the action of OH radicals produced in the plasma.
Study on Micro-Pressure Drive in the KKM Low-Permeability Reservoir
Heng Zhang, Mibang Wang, Wenqi Ke, Xiaolong Li, Shengjun Yang, Weihua Zhu
June 7, 2024 (v1)
Keywords: Artificial Intelligence, artificial lift, low-permeability reservoir, micro-pressure drive development technology
Kazakhstan has abundant resources of low-permeability oil reservoirs, among which the KKM low-permeability oil reservoir has geological reserves of 3844 × 104 t and a determined recoverable reserve of 1670 × 104 t. However, the water flooding efficiency is only 68%, and the recovery efficiency is as low as 32%. The development of the reservoir faces challenges such as water injection difficulties and low oil production from wells. In order to further improve the oil recovery rate of this reservoir, our team developed micro-pressure-driven development technology based on pressure-driven techniques by integrating theories of fluid mechanics and artificial intelligence. We also combined this with subsequent artificial lift schemes, resulting in a complete set of micro-pressure-driven process technology. The predicted results indicate that after implementing micro-pressure-driven techniques, a single well group in the KKM oilfield can achieve a daily oil production increase of 32.08 t, dem... [more]
A Molecularly Imprinted Fluorescence Sensor Based on Upconversion-Nanoparticle-Grafted Covalent Organic Frameworks for Specific Detection of Methimazole
Yan Liu, Tian Zhao, Shuzhen Li, Yichuan Cao, Guozhen Fang
June 7, 2024 (v1)
Subject: Materials
Keywords: covalent organic frameworks, methimazole, molecularly imprinted polymers, upconversion nanoparticles
Rapid detection and sensitive analysis of MMZ is of great importance for food safety. Herein, a fluorescent molecularly imprinted sensor based on upconversion nanoparticles (UCNPs) grafted onto covalent organic frameworks (COFs) was designed for the detection of MMZ. COFs with a high specific surface area and excellent affinity serve as substrates for grafting of UCNPs, which can inhibit the aggregation burst of UCNPs and improve the mass transfer rate of the sensor. Through a series of characterizations, it was found that the proposed UCNP-grafted COFs@MIP-based sensor had good optical stability, high adsorption efficiency, strong anti-interference ability, and high sensitivity owing to the integration of the advantages of UCNPs, COFs and MIPs. Under the optimal conditions, a good linear relationship was presented between the fluorescence intensity of UCNP-grafted COFs@MIPs and the methimazole concentration in the range of 0.05−3 mg L−1, and the detection limit was 3 μg L−1. The as-pr... [more]
Fluid Dynamics Investigation in a Cold Flow Model of Internal Recycle Quadruple Fluidized Bed Coal Pyrolyzer
Xuepu Cao, Haoran Yu, Jianying Wang, Lilong Zhou, Yongqi Hu
June 7, 2024 (v1)
Keywords: Computational Fluid Dynamics, coupling of pyrolyzer and combustor, experimental model, hydrodynamic characteristics, IR-QFBP
Internal recycle quadruple fluidized bed pyrolyzer (IR-QFBP) consists of a dual fluidized bed pyrolyzer and a dual fluidized bed combustor and is proposed in this work. It is a new kind of efficient fluidized bed with high pyrolysis and energy efficiency. IR-QFBP may attract extensive attention because of its compact structure. Cold hydrodynamic characteristics of IR-QFBP are the bases of modeling and designing for the hot one. To fully understand the hydrodynamic characteristics of IR-QFBP, a cold flow model on a laboratory scale was designed and set up; furthermore, the two-fluid model (TFM) based simulation was also carried out. The pressure profiles, fluidization states, velocity profiles, and circulation rates of a solid powder at different operation conditions in IR-QFBP were investigated. The results showed that the stable internal circulation of solid powder can be achieved in IR-QFBP. And different circulation characteristics can be obtained by adjusting the operating conditio... [more]
Enhancing Alkaline Protease Stability through Enzyme-Catalyzed Crosslinking and Its Application in Detergents
Haichuan Yang, Xiankun Ren, Yating Zhao, Tengjiao Xu, Jing Xiao, Hao Chen
June 7, 2024 (v1)
Subject: Biosystems
Keywords: alkaline protease, laundry detergent, stability, TG enzyme
Enzymatic additives, particularly alkaline proteases, play a crucial role in enhancing detergent effectiveness against protein-based stains. Despite advancements in enzyme stabilization techniques, there is a need for innovative strategies to further improve protease stability in laundry detergents. However, research exploring the utilization of substrate imprinting technology to achieve this objective remains limited. Therefore, this study aims to enhance the stability of alkaline proteases in laundry detergents by employing casein as an imprinting substrate and utilizing transglutaminase-mediated (TGase) crosslinking to modify proteases 102 and 306. The optimal temperature, pH, and thermal stability of the modified alkaline proteases 102 and 306 showed no significant changes. However, these two modified alkaline proteases exhibited varying degrees of improvement in stability among the 14 detergent additives tested. Under 40 °C incubation for 24 h, the relative enzyme activity of modi... [more]
Characteristics of Soil Heavy Metal Pollution and Health Risks in Chenzhou City
Yingfeng Kuang, Xiaolong Chen, Chun Zhu
June 7, 2024 (v1)
Subject: Environment
Keywords: Chenzhou, health risks, heavy metals, potential ecological risks, soil
The objective of this inquiry is to illuminate the attributes of heavy metal contamination and evaluate the potential ecological hazards inherent in the surface soil of Chenzhou City. A comprehensive analysis was conducted on 600 systematically collected soil samples within the study area, utilizing enrichment factors, geo-accumulation indices, comprehensive pollution indices, potential ecological hazard indices, and health risk assessment models to evaluate the degree of heavy metal contamination in the soil, potential ecological risks, and associated health hazards. The findings reveal that the average enrichment factor (EF) for each heavy metal is below 2, with the hierarchy from highest to lowest being Hg > Cd > Cu > Pb > Ni > Zn > Cr > As. Approximately 78.67% of soil samples exhibit no pollution to weak pollution levels based on heavy metal enrichment factors. Moreover, the comprehensive pollution index (IPIN) indicates that 95.17% of soil samples are within safe and pollution-fr... [more]
Exploring Vortex−Flame Interactions and Combustion Dynamics in Bluff Body-Stabilized Diffusion Flames: Effects of Incoming Flow Velocity and Oxygen Content
Mingmin Chen, Minwei Zhao, Zhihao Wang, Xinbo Huang, Hongtao Zheng, Fuquan Deng
June 7, 2024 (v1)
Keywords: Computational Fluid Dynamics, diffusion combustion, dynamic combustion characteristic, oxygen content, vortex shedding
An afterburner encounters two primary features: high incoming flow velocity and low oxygen concentration in the incoming airflow, which pose substantial challenges and contribute significantly to the deterioration of combustion performance. In order to research the influence of oxygen content on the dynamic combustion characteristics of the afterburner under various inlet velocities, the effect of oxygen content (14−23%) on the field structure of reacting bluff body flow, flame morphology, temperature pulsation, and pressure pulsation of the afterburner at different incoming flow velocities (0.1−0.2 Ma) was investigated in this study by using a large eddy simulation method. The results show that two different instability features, BVK instability and KH instability, are observed in the separated shear layer and wake, and are influenced by changes in the O2 mass fraction and Mach number. The oxygen content and velocity affected the oscillation amplitude of the downstream flow. As the O2... [more]
Efficiency of Hydrogen Peroxide and Fenton Reagent for Polycyclic Aromatic Hydrocarbon Degradation in Contaminated Soil: Insights from Experimental and Predictive Modeling
Mahdia Smara, Razika Khalladi, Nadji Moulai-Mostefa, Kamilia Madi, Dorsaf Mansour, Sabrina Lekmine, Ouided Benslama, Hichem Tahraoui, Jie Zhang, Abdeltif Amrane
June 7, 2024 (v1)
Keywords: chemical oxidation, Gaussian process regression, hydrogen peroxide, Improved Grey Wolf Optimizer, polycyclic aromatic hydrocarbons, soil pollution, the Fenton reagent
This study investigates the degradation kinetics of polycyclic aromatic hydrocarbons (PAHs) in contaminated soil using hydrogen peroxide (H2O2) and the Fenton process (H2O2/Fe2+). The effect of oxidant concentration and the Fenton molar ratio on PAH decomposition efficiency is examined. Results reveal that increasing H2O2 concentration above 25 mmol/samples leads to a slight increase in the rate constants for both first- and second-order reactions. The Fenton process demonstrates higher efficiency in PAH degradation compared to H2O2 alone, achieving decomposition yields ranging from 84.7% to 99.9%. pH evolution during the oxidation process influences PAH degradation, with alkaline conditions favoring lower elimination rates. Fourier-transform infrared (FTIR) spectroscopy analysis indicates significant elimination of PAHs after treatment, with both oxidants showing comparable efficacy in complete hydrocarbon degradation. The mechanisms of PAH degradation by H2O2 and the Fenton process i... [more]
Petri Net Model Predictive Control Method for Batch Chemical Systems
Zexuan Lin, Jiazhong Zhou, Shasha Sun, Jiliang Luo, Jiabing Zhang
June 7, 2024 (v1)
Keywords: batch chemical system, heuristic function, Model Predictive Control, real-time scheduling, timed Petri net
In order to address the problem of the real-time scheduling and control of batch chemical systems, this work proposes a model predictive control method based on Petri nets. First, a method is presented to construct a batch chemical system’s timed Petri net model. Second, a control structure is designed to augment the Petri net model to control the valves. This results in timed Petri nets that formally represent the process specifications of a batch chemical system. Third, a model predictive control method is developed to schedule and control timed Petri nets, where a proposed heuristic function is utilized to perform the optimization computation. The model parameters are dynamically adjusted using online data, and both scheduling and valve control instructions are calculated in real time. Finally, a series of experiments is carried out in a beer canning plant to verify the proposed method. According to the experimental results, the scheduling and control problem can be solved in real t... [more]
Northern Lights: Prospecting Efficiency in Europe’s Renewable Energy Sector
Yen-Hsing Hung, Fu-Chiang Yang
June 7, 2024 (v1)
Keywords: behavioral coefficient, Data Envelopment Analysis, Northern European, Renewable and Sustainable Energy
Northern European nations are at the forefront of renewable energy adoption but face challenges in optimizing energy conversion efficiency. There is a lack of detailed understanding of how behavioral factors affect the efficiency of renewable energy conversion in these countries. This study aims to evaluate and compare the renewable energy conversion efficiency of Northern European countries, intending to inform strategic policy making and identify best practices for technology deployment in the renewable energy sector. Employing a Data Envelopment Analysis (DEA) model, the study integrates behavioral economic parameters—specifically, the aversion loss and gain significance coefficients—to assess the efficiency of renewable energy conversion, accounting for psychological factors in decision making. A comprehensive sensitivity analysis was conducted, varying the gain significance coefficient while maintaining the aversion loss coefficient at constant levels. This experiment was designed... [more]
Performance of a Solar-Driven Photocatalytic Membrane Reactor for Municipal Wastewater Treatment
Mirela Alina Constantin, Lucian Alexandru Constantin, Ioana Alexandra Ionescu, Cristina Mihaela Nicolescu, Marius Bumbac, Olga Tiron
June 7, 2024 (v1)
Subject: Materials
Keywords: advanced treatment, membrane processes, photocatalysis, PMR, solar light, Wastewater
The increasing demand for efficient wastewater treatment technologies, driven by global population growth and industrialisation, highlights the necessity for advanced, reliable solutions. This study investigated the efficacy of a slurry photocatalytic membrane reactor (PMR) for the advanced removal of organic pollutants, quantified via chemical oxygen demand (COD), under natural and simulated solar light irradiation. Employing two variants of iron-doped titania as photocatalysts and a polysulfone-based polymeric membrane for the separation process, the investigation showcased COD removal efficiencies ranging from 66−85% under simulated solar light to 52−81% under natural sunlight over a 7 h irradiation period. The overall PMR system demonstrated COD removal efficiencies of 84−95%. The results confirmed the enhanced photocatalytic activity afforded by iron doping and establish solar-powered slurry PMRs as an effective, low-energy, and environmentally friendly alternative for the advance... [more]
A New Method for Numerical Simulation of Coalbed Methane Pilot Horizontal Wells—Taking the Bowen Basin C Pilot Area in Australia as an Example
Xidong Wang, Lijiang Duan, Songhang Zhang, Shuheng Tang, Jianwei Lv, Xudong Li
June 7, 2024 (v1)
Keywords: CBM pilot well, history matching, sensitivity analysis, uncertainty analysis
Coalbed methane (CBM) pilot wells typically exhibit a short production period, necessitating evaluation of their estimated ultimate recovery (EUR) through numerical simulation. Utilizing limited geological data from the pilot areas to finish history matching and subsequent production forecasting presents substantial challenges. This paper introduces a comprehensive numerical simulation workflow for CBM pilot wells, encompassing the following steps. Initially, geological parameters are categorized into two groups based on their statistical distribution trends: trend parameters (i.e., gas content, permeability, Langmuir volume, and Langmuir pressure) and non-trend parameters (i.e., fracture porosity, gas−water relative permeability, and rock compressibility). The probability method is employed to ascertain the probable high and low limits for trend parameter distributions, while empirical or analogous methods are applied to define the boundaries for non-trend parameters. Subsequently, th... [more]
Analysis of Multi-Fracture Extension Pattern of Horizontal Wells in Shale Reservoirs under Natural Fracture Perturbation
Jianbo Wang, Huan Zhao, Huifang Liu, Wei Li, Junru Li, Pengfei Tang, Minghui Zhang, Yanling Liu, Siqi Wang, Xingsheng Xu, Tiansu He
June 7, 2024 (v1)
Keywords: fracture networks, horizontal well, multi-fractures, natural fracture, shale reservoirs
There are many natural fractures in shale reservoirs, changes in hydraulic fracture extension patterns. In the paper, a multi-fracture extension finite element model for horizontal wells in shale reservoirs under the disturbance of natural fractures is established by combining the actual geological parameters and construction parameters of a horizontal well multi-fracturing operation in X oilfield to analyze the effects of the difference in geostress, elastic modulus, angle of natural fractures, and the number of natural fracture groups on the hydraulic fracture extension. The results show that with the increase in ground stress difference and natural fracture angle, hydraulic fractures are more likely to penetrate the natural fractures; with the increase in elastic modulus, the fracture stress and tip stress increase, the volume of rupture unit, the fracture extension width and the pore pressure concentration area decrease, and it is easy to form a long and narrow fracture; with the i... [more]
Solar-Assisted Carbon Capture Process Integrated with a Natural Gas Combined Cycle (NGCC) Power Plant—A Simulation-Based Study
Yasser Abbas Hammady Al-Elanjawy, Mustafa Yilmaz
June 7, 2024 (v1)
Keywords: Carbon Capture, Carbon Dioxide, natural gas combustion cycle, SAM
In the realm of Natural Gas Combined Cycle (NGCC) power plants, it is crucial to prioritize the mitigation of CO2 emissions to ensure environmental sustainability. The integration of post-combustion carbon capture technologies plays a pivotal role in mitigating greenhouse gas emissions enhancing the NGCC’s environmental profile by minimizing its carbon footprint. This research paper presents a comprehensive investigation into the integration of solar thermal energy into the Besmaya Natural Gas Combined Cycle (NGCC) power plant, located in Baghdad, Iraq. Leveraging advanced process simulation and modeling techniques employing Aspen Plus software, the study aims to evaluate the performance and feasibility of augmenting the existing NGCC facility with solar assistance for post-carbon capture. The primary objective of this research is to conduct a thorough simulation of the Besmaya NGCC power plant under its current operational conditions, thereby establishing a baseline for subsequent ana... [more]
Showing records 1344 to 1368 of 43292. [First] Page: 1 51 52 53 54 55 56 57 58 59 Last
(0.13 seconds)
[Show List of Record Types]

[0.14 s]