bluuebunny/crossref_metadata_2025 huggingface dataset:
Key Portfolio Selection Criteria for Sustainable Construction
Authors: Anjamrooz Taha , El-Sayegh Sameh M. , Romdhane Lotfi
Published: June 2024

Selecting the best projects and programs is of paramount importance to the success of organizations in the construction industry for the employer, clients, and developers. The existing selection criteria in the literature are tailored toward traditional construction projects. However, with the current move toward sustainable construction, there is a need to incorporate sustainability-specific criteria in the process portfolio selection. This study aims to identify and evaluate the sustainability-specific project selection criteria for construction organizations from the client’s perspective; this research topic is significant because developers/clients do not always consider sustainability criteria when selecting their portfolio of projects. The research methodology of this study consists of a literature review, identifying the sustainability criteria into an integrated list, and a survey to weight and rank the criteria. Sixteen criteria were identified through an extensive review of the related literature. These criteria were categorized based on three sustainability pillars: environmental, social, and economic. The environmental pillar includes six selection criteria, which are energy use, material use, water use, land use, pollution, and waste management. The social pillar consists of five selection criteria, which include health and safety, employee training and education, improvement in infrastructure, relation with local communities, and alternative transportation. The economic pillar consists of five selection criteria, which include life cycle cost, contribution to GDP, employment creation, innovation and technology, and use of national suppliers. A survey was developed and circulated to specialists in the construction industry in the United Arab Emirates (UAE). The weights for the sustainability selection criteria were assessed by using the Analytic Hierarchy Process (AHP) method. The results show that the environmental group is the most important group among the pillars of sustainability, with a weight of 0.520, compared with the social and the economic pillars, which had weights of 0.214 and 0.266, respectively.
Effect of Bidirectional Hysteretic Dampers on the Seismic Performance of Skewed Multi-Span Highway Bridges
Authors: Aldea Sofía , Bazáez Ramiro , Heresi Pablo , Astroza Rodrigo
Published: June 2024

Bridges are one of the most critical and costly structures on road networks. Thus, their integrity and operation must be preserved to prevent safety concerns and connectivity losses after seismic events. Recent large-magnitude earthquakes have revealed a series of vulnerabilities in multi-span highway bridges. In particular, skewed bridges have been severely damaged due to their susceptibility to developing excessive in-plane deck rotations and span unseating. Although seismic design codes have been updated to prescribe larger seating lengths and have incorporated unseating prevention devices, such as shear keys and cable restrainers, research on the seismic performance of skewed bridges with passive energy-dissipation devices is still limited. Therefore, this study focuses on assessing the effectiveness of implementing hysteretic dampers on skewed bridges. With that aim, dampers with and without recentering capabilities are designed and incorporated in representative Chilean skewed bridges to assess their contribution to seismic performance. Three-dimensional nonlinear finite element models, multiple-stripe analysis, and fragility curves are utilized to achieve this objective. The results show that incorporating bidirectional dampers can effectively improve the seismic performance of skewed bridges at different hazard levels by limiting in-plane deck rotations independently of their skew angle. Additionally, the influence of external shear keys and damper hysteretic behavior is analyzed, showing that these parameters have a low influence on bridge performance when bidirectional dampers are incorporated.
An Improved Zonal Ventilation Control Method of Waiting Hall of High-Speed Railway Station Based on Real-Time Occupancy
Authors: Zhou Pei , Zhou Jintao , Tang Yu , Ma Zicheng , Yao Ming , Zhu Jian , Si Huanyu
Published: June 2024

The random movement of occupants in a high-speed railway station results in a more complex indoor environment. In this study, the indoor thermal environment and the thermal comfort in summer were investigated via field measurements and questionnaires in the waiting hall of a high-speed railway station. The results showed that there was an uneven horizontal temperature distribution in the area, and over 30% of the passengers were dissatisfied with the air conditioning system. In order to improve the control of the indoor temperature as well as reduce the energy consumption of the air conditioning system, an improved zonal control strategy and AMPC control optimization algorithm based on real-time people are proposed, and different control strategies are modeled and simulated using MATLAB/Simulink. It is concluded that the improved zonal control method proposed in this paper can save 28.04% of the fan energy consumption compared with the traditional control strategy.
Integrated ATAC-seq and RNA-seq Analysis of In Vitro Cultured Skeletal Muscle Satellite Cells to Understand Changes in Cell Proliferation
Authors: Ren Zeyu , Zhang Siyi , Shi Liangyu , Zhou Ao , Lin Xin , Zhang Jing , Zhu Xiusheng , Huang Lei , Li Kui
Published: June 2024

Skeletal muscle satellite cells, the resident stem cells in pig skeletal muscle, undergo proliferation and differentiation to enable muscle tissue repair. The proliferative and differentiative abilities of these cells gradually decrease during in vitro cultivation as the cell passage number increases. Despite extensive research, the precise molecular mechanisms that regulate this process are not fully understood. To bridge this knowledge gap, we conducted transcriptomic analysis of skeletal muscle satellite cells during in vitro cultivation to quantify passage number-dependent changes in the expression of genes associated with proliferation. Additionally, we explored the relationships between gene transcriptional activity and chromatin accessibility using transposase-accessible chromatin sequencing. This revealed the closure of numerous open chromatin regions, which were primarily located in intergenic regions, as the cell passage number increased. Integrated analysis of the transcriptomic and epigenomic data demonstrated a weak correlation between gene transcriptional activity and chromatin openness in expressed genic regions; although some genes (e.g., GNB4 and FGD5) showed consistent relationships between gene expression and chromatin openness, a substantial number of differentially expressed genes had no clear association with chromatin openness in expressed genic regions. The p53-p21-RB signaling pathway may play a critical regulatory role in cell proliferation processes. The combined transcriptomic and epigenomic approach taken here provided key insights into changes in gene expression and chromatin openness during in vitro cultivation of skeletal muscle satellite cells. These findings enhance our understanding of the intricate mechanisms underlying the decline in cellular proliferation capacity in cultured cells.
A Combination of Amide Proton Transfer, Tumor Blood Flow, and Apparent Diffusion Coefficient Histogram Analysis Is Useful for Differentiating Malignant from Benign Intracranial Tumors in Young Patients: A Preliminary Study
Authors: Tanaka Fumine , Maeda Masayuki , Nakayama Ryohei , Inoue Katsuhiro , Kishi Seiya , Kogue Ryota , Umino Maki , Kitano Yotaro , Obara Makoto , Sakuma Hajime
Published: June 2024

Purpose: To evaluate the amide proton transfer (APT), tumor blood flow (TBF), and apparent diffusion coefficient (ADC) combined diagnostic value for differentiating intracranial malignant tumors (MTs) from benign tumors (BTs) in young patients, as defined by the 2021 World Health Organization classification of central nervous system tumors. Methods: Fifteen patients with intracranial MTs and 10 patients with BTs aged 0–30 years underwent MRI with APT, pseudocontinuous arterial spin labeling (pCASL), and diffusion-weighted imaging. All tumors were evaluated through the use of histogram analysis and the Mann–Whitney U test to compare 10 parameters for each sequence between the groups. The diagnostic performance was evaluated using receiver operating characteristic (ROC) curve analysis. Results: The APT maximum, mean, 10th, 25th, 50th, 75th, and 90th percentiles were significantly higher in MTs than in BTs; the TBF minimum (min) was significantly lower in MTs than in BTs; TBF kurtosis was significantly higher in MTs than in BTs; the ADC min, 10th, and 25th percentiles were significantly lower in MTs than in BTs (all p < 0.05). The APT 50th percentile (0.900), TBF min (0.813), and ADC min (0.900) had the highest area under the curve (AUC) values of the parameters in each sequence. The AUC for the combination of these three parameters was 0.933. Conclusions: The combination of APT, TBF, and ADC evaluated through histogram analysis may be useful for differentiating intracranial MTs from BTs in young patients.
The Stress Index as a Predictor of Mortality in Patients with Isolated Moderate to Severe Traumatic Brain Injury
Authors: Huang Ching-Ya , Rau Cheng-Shyuan , Huang Chun-Ying , Su Wei-Ti , Hsu Shiun-Yuan , Hsieh Ching-Hua
Published: June 2024

Background: The Stress Index (SI), calculated as the ratio of blood glucose to serum potassium levels, is a promising prognostic marker in various acute care settings. This study aimed to evaluate the utility of the SI for predicting mortality in patients with isolated moderate-to-severe traumatic brain injury (TBI). Methods: This retrospective cohort study included adult trauma patients (aged ≥ 20 years) with isolated moderate to severe TBI (Abbreviated Injury Scale ≥ 3 for only head region) treated from 2009–2022. The SI was computed from the initial glucose and potassium levels upon arrival at the emergency department. Logistic regression models were used to assess the association between the SI and mortality after adjusting for relevant covariates. The most effective threshold value of the SI for predicting mortality was identified using receiver operating characteristic (ROC) analysis. Results: Among the 4357 patients with isolated moderate and severe TBI, 463 (10.6%) died. Deceased patients had a significantly higher SI (61.7 vs. 44.1, p < 0.001). In multivariate analysis, higher SI independently predicted greater mortality risk (odds ratio (OR) 6.70, 95% confidence interval (CI) 1.66–26.99, p = 0.007). The optimal SI cutoff for predicting mortality was 48.50 (sensitivity 62.0%, specificity 71.4%, area under the curve 0.724). Patients with SI ≥ 48.5 had nearly two-fold higher adjusted mortality odds compared to those below the threshold (adjusted OR 1.94, 95% CI 1.51–2.50, p < 0.001). Conclusions: SI is a useful predictor of mortality in patients with isolated moderate-to-severe TBI. Incorporating SI with standard clinical assessments could enhance risk stratification and management approaches for this patient population.
Immunohistochemical Analysis of Dentigerous Cysts and Odontogenic Keratocysts Associated with Impacted Third Molars—A Systematic Review
Authors: Almeida Luis , Lloyd David , Boettcher Daniel , Kraft Olivia , Zammuto Samuel
Published: June 2024

Objective: This systematic review investigates the diagnostic, prognostic, and therapeutic implications of immunohistochemical markers in dentigerous cysts (DCs) and odontogenic keratocysts (OKCs) associated with impacted third molars. Materials and Methods: A comprehensive search strategy was employed across major databases including MEDLINE/PubMed, EMBASE, and Web of Science, from the inception of the databases to March 2024. Keywords and Medical Subject Heading (MeSH) terms such as “dentigerous cysts”, “odontogenic keratocysts”, “immunohistochemistry”, “Ki-67”, and “p53” were used. The PRISMA 2020 guidelines were followed to ensure methodological rigor. Inclusion criteria encompassed studies on humans and animals providing definitive diagnoses or specific signs and symptoms related to DCs and OKCs, with results on protein expression derived from immunohistochemistry, immune antibody, proteomics, or protein expression methods. Results: Of the 159 studies initially identified, 138 met the inclusion criteria. Our analysis highlighted significantly higher expressions of Ki-67 (22.1% ± 4.7 vs. 10.5% ± 3.2, p < 0.001), p53 (15.3% ± 3.6 vs. 5.2% ± 1.9, p < 0.001), and Bcl-2 (18.4% ± 3.2 vs. 8.7% ± 2.4, p < 0.001) in OKCs compared to DCs, indicating a higher proliferative index, increased cellular stress, and enhanced anti-apoptotic mechanisms in OKCs. Additionally, PCNA levels were higher in OKCs (25.6% ± 4.5 vs. 12.3% ± 3.1, p < 0.001). Genetic mutations, particularly in the PTCH1 gene, were frequently observed in OKCs, underscoring their aggressive behavior and potential malignancy. Conclusions: The findings emphasize the significant role of immunohistochemical markers in distinguishing between DCs and OKCs, with elevated levels of Ki-67, p53, Bcl-2, and PCNA in OKCs suggesting a higher potential for growth and recurrence. Genetic insights, including PTCH1 mutations, further support the need for personalized treatment approaches. These markers enhance diagnostic accuracy and inform targeted therapeutic strategies, potentially transforming patient management in oral and maxillofacial surgery.
Exergoeconomic Analysis and Optimization of a Biomass Integrated Gasification Combined Cycle Based on Externally Fired Gas Turbine, Steam Rankine Cycle, Organic Rankine Cycle, and Absorption Refrigeration Cycle
Authors: Ren Jie , Xu Chen , Qian Zuoqin , Huang Weilong , Wang Baolin
Published: June 2024

Adopting biomass energy as an alternative to fossil fuels for electricity production presents a viable strategy to address the prevailing energy deficits and environmental concerns, although it faces challenges related to suboptimal energy efficiency levels. This study introduces a novel combined cooling and power (CCP) system, incorporating an externally fired gas turbine (EFGT), steam Rankine cycle (SRC), absorption refrigeration cycle (ARC), and organic Rankine cycle (ORC), aimed at boosting the efficiency of biomass integrated gasification combined cycle systems. Through the development of mathematical models, this research evaluates the system’s performance from both thermodynamic and exergoeconomic perspectives. Results show that the system could achieve the thermal efficiency, exergy efficiency, and levelized cost of exergy (LCOE) of 70.67%, 39.13%, and 11.67 USD/GJ, respectively. The analysis identifies the combustion chamber of the EFGT as the component with the highest rate of exergy destruction. Further analysis on parameters indicates that improvements in thermodynamic performance are achievable with increased air compressor pressure ratio and gas turbine inlet temperature, or reduced pinch point temperature difference, while the LCOE can be minimized through adjustments in these parameters. Optimized operation conditions demonstrate a potential 5.7% reduction in LCOE at the expense of a 2.5% decrease in exergy efficiency when compared to the baseline scenario.
Thermoacoustic Modeling of Cryogenic Hydrogen
Authors: Matveev Konstantin I. , Leachman Jacob W.
Published: June 2024

Future thermoacoustic cryocoolers employing hydrogen as a working fluid can reduce reliance on helium and improve hydrogen liquefaction processes. Traditional thermoacoustic modeling methods often assume ideal-gas thermophysical properties and neglect finite-amplitude effects. However, these assumptions are no longer valid for hydrogen near saturated states. In this study, a comparison between the results of computational fluid dynamics simulations using actual hydrogen properties and a low-amplitude, ideal-gas thermoacoustic theory was carried out in a canonical plate-based stack configuration at a mean pressure of 5 bar. It was found that the simplified analytical theory significantly underpredicts the cooling power of hydrogen-filled thermoacoustic setups, especially at lower temperatures in high-amplitude, traveling-wave arrangements. In addition, a thermoacoustic prime mover was modeled at higher temperatures, demonstrating very close agreement with the ideal-gas-based theory. The CFD approach is recommended for the design of future hydrogen-based cryocoolers at temperatures below 80 K.
New Insights into Gas-in-Oil-Based Fault Diagnosis of Power Transformers
Authors: Laburú Felipe M. , Cabral Thales W. , Gomes Felippe V. , de Lima Eduardo R. , Filho José C. S. S. , Meloni Luís G. P.
Published: June 2024

The dissolved gas analysis of insulating oil in power transformers can provide valuable information about fault diagnosis. Power transformer datasets are often imbalanced, worsening the performance of machine learning-based fault classifiers. A critical step is choosing the proper evaluation metric to select features, models, and oversampling techniques. However, no clear-cut, thorough guidance on that choice is available to date. In this work, we shed light on this subject by introducing new tailored evaluation metrics. Our results and discussions bring fresh insights into which learning setups are more effective for imbalanced datasets.
Correction: Lipowska et al. Switching Behavior in the Polish Energy Market—The Importance of Resistance to Change. Energies 2024, 17, 306
Authors: Lipowska Ilona , Lipowski Marcin , Dudek Dariusz , Mącik Radosław
Published: June 2024

In the previously published article [...]
An Enhanced Ageing Model for Solid-State Batteries
Authors: Scaltrito Paolo , Lanjan Amirmasoud , Srinivasan Seshasai
Published: June 2024

The emphasis in the automotive industry towards sustainable mobility has led to a significant interest in hybrid-electric drive-trains with high energy density batteries. Addressing the needs of this strategy, the battery market is exploring new technologies to improve the safety and lifespan of electric vehicles. To this end, there is a focus on the all-solid-state battery (ASSB) technology for its cycle capabilities. Filling the current void in the literature pertaining to accurate ageing models for ASSBs, in the present work, we propose an enhanced version of the numerical ageing model, originally developed for liquid electrolyte based batteries, to forecast the development of the solid electrolyte interface layer that is the major cause of battery capacity fading. The model has been tested on prototype batteries and reveals an accuracy of 99%. The capacity fade in ASSBs has been investigated under different conditions and the enhanced ageing model has been validated using experimental data from these batteries. The findings suggest that there is potential for solid-state batteries to be commercialized, although significant work is needed to match the manufacturing level of lithium-ion batteries embedded with liquid electrolytes.
Experimental Study of Clamping Pressure during Step Loading of Power Transformer with and without Prior Energisation
Authors: Madshaven Inge , Enoksen Henrik , Lundgaard Lars E. , Jaufer Stefan , Krause Christoph , Prašnikar Borut , Mjelve Asgeir
Published: June 2024

The electrification of society, increasing renewable energy sources and mobility charging lead to new loading patterns for power transformers. Dynamic load conditions induce enhanced mechanical stress on the transformers’ windings, potentially causing degradation of the solid insulation over time and compromising the transformer’s short-circuit withstand capability. Thermal expansion of the windings, caused by losses in the copper conductors, occurring as the transformer is loaded, increases the stress. Conversely, magnetic losses in the core and tie plate expansion contribute to a reduction in stress. This paper presents the effect of step changes in core losses and copper losses by on-line measurements of the clamping pressure, to better understand the mechanical stresses acting upon the solid insulation cellulose materials. Energisation is found to decrease the clamping pressure following warming up of the transformer, and loading the transformer increased the pressure as the windings increased in temperature. The converse effect was found when unloading and de-energising. The on-line monitoring system provides a new and important step towards ensuring the short-circuit performance of power transformers.
A Review of Modern Electric Vehicle Innovations for Energy Transition
Authors: Jiang Bi-Hai , Hsu Chao-Chung , Su Nai-Wei , Lin Chun-Cheng
Published: June 2024

As climate change worsens and the importance of energy security grows, numerous countries have adopted energy transition as a key policy objective. Electric vehicles (EVs) play a pivotal role in this transition by diminishing reliance on fossil fuels and reducing emissions of carbon dioxide and other harmful gases. While EVs are poised to be a crucial technology for achieving energy transition, substantial advancements in technology, infrastructure development, and policy support are essential for their full potential to be realized. This review examines the latest advancements in EV technology and market trends, and also addresses the challenges facing EVs and the potential opportunities for future development.
Intraday Electricity Price Forecasting via LSTM and Trading Strategy for the Power Market: A Case Study of the West Denmark DK1 Grid Region
Authors: Kılıç Deniz Kenan , Nielsen Peter , Thibbotuwawa Amila
Published: June 2024

For several stakeholders, including market players, customers, grid operators, policy-makers, investors, and energy efficiency initiatives, having a precise estimate of power pricing is crucial. It is easier for traders to plan, purchase, and sell power transactions with access to accurate electricity price forecasting (EPF). Although energy production and consumption topics are widely discussed in the literature, EPF and renewable energy trading studies receive less attention, especially for intraday market modeling and forecasting. Considering the rapid development of renewable energy sources, the article highlights the significance of integrating the deep learning model, long short-term memory (LSTM), with the proper trading strategy for short-term hourly renewable energy trading by utilizing two different spot markets. Day-ahead and intraday markets are taken into account for the West Denmark grid region (DK1). The time series analysis indicates that LSTM yields superior results compared to other benchmark machine learning algorithms. Using the predictions obtained by LSTM and the recommended trading strategy, promising profit values are achieved for the DK1 wind and solar energy use case, which ensures future motivation to develop a general and flexible model for global data.
The Feasibility of Heat Extraction Using CO2 in the Carbonate Reservoir in Shandong Province, China
Authors: Liu Xiao , Zhang Feng , Song Shuailiang , Tan Xianfeng , Feng Guanhong
Published: June 2024

CO2 is being considered as an effective alternative working fluid for geothermal applications due to its superior fluid dynamics and heat transfer properties compared to water. Utilizing sedimentary rocks for geothermal energy recovery through a CO2-plume geothermal system, especially in carbonate reservoirs, has been shown to be a practical approach that eliminates the need for hydraulic fracturing. However, uncertainties remain regarding the thermal and hydraulic behavior, particularly the chemical interactions between CO2 and carbonate rocks. This study develops a comprehensive wellbore–reservoir coupling reactive transport model based on specific information obtained from the Ordovician limestone geothermal reservoir in Shandong, China. The model aims to assess the feasibility of heat extraction in carbonate reservoirs by evaluating the heat extraction performance and fluid–rock interaction. The results indicate a rapid temperature drop after CO2 breakthrough due to the Joule–Thomson effect. Simultaneously, the fluid transitions into and maintains a two-phase state throughout the operation. Chemical reactions within the reservoir are not aggressive since complete mixing between unsaturated water and CO2 only occurs in the vicinity of the production well, highlighting the potential of utilizing carbonate reservoirs for efficient heat extraction in geothermal systems. Further research is needed to optimize the performance of CO2-based geothermal systems in carbonate reservoirs.
Pipeline Infrastructure for CO2 Transport: Cost Analysis and Design Optimization
Authors: Solomon Mithran Daniel , Scheffler Marcel , Heineken Wolfram , Ashkavand Mostafa , Birth-Reichert Torsten
Published: June 2024

Meeting Germany’s climate targets urgently demands substantial investment in renewable energies such as hydrogen, as well as tackling industrial CO2 emissions with a strong CO2 transport infrastructure. This is particularly crucial for CO2-heavy industries such as steel, cement, lime production, power plants, and chemical plants, given Germany’s ban on onshore storage. The CO2 transport network is essential for maintaining a circular economy by capturing, transporting, and either storing or utilizing CO2. This study fills gaps in CO2 pipeline transport research, examining pipeline diameters, costs, and pressure drop, and providing sensitivity analysis. Key findings show that the levelized cost of CO2 transport (LCO2T) ranges from 0.25 €/t to 55.82 €/t based on varying transport masses (1000 t/day to 25,000 t/day) and distances (25 km to 500 km), with compression costs pushing LCO2T to 33.21 €/t to 92.82 €/t. Analyzing eight pipeline diameters (150 mm to 500 mm) and the impact of CO2 flow temperature on pressure loss highlights the importance of selecting optimal pipeline sizes. Precise booster station placement is also crucial, as it significantly affects the total LCO2T. Exploring these areas can offer a more thorough understanding of the best strategies for developing cost-effective, efficient, and sustainable transport infrastructure.
Study on Conventional Island Retrofit Strategies for Converting Coal-Fired Power Plants to Nuclear Power Stations in China
Authors: Luo Bixiong , Zhang Li , Li Wei , Zhu Xinwei , Ye Yongjian , Su Yanlin
Published: June 2024

The conversion of coal-fired power plants to nuclear power stations is a potential method for decarbonizing coal power and offers a pathway for low-carbon development in China’s power industry. This paper focuses on retrofitting China’s coastal coal-fired power stations and compares the potential nuclear reactor technologies for the retrofit: China’s mainstream pressurized water reactor and the commercially operated fourth-generation high-temperature gas-cooled reactor (HTGR). The analysis compares the degree of matching between the two technologies and coal-fired power stations in terms of unit capacity, thermal system parameters, unit speed, structural dimensions, and weight, which significantly impact the retrofit scheme. The results indicate that HTGR is more compatible with coal-fired power plants and is recommended as the type of nuclear reactor technology to be retrofitted. The study selected the 210 MWe High-Temperature Gas-Cooled Reactor Pebble-Bed Module (HTR-PM) as the reactor technology for retrofitting a typical 300 MW class subcritical coal-fired unit. Based on the concept of subcritical parameters upgrading, the potential analysis and strategy study of retrofit is carried out in terms of the turbine, the main heat exchange equipment, the main pumps, and the main thermal system pipelines in the conventional island. The results indicate that the conventional island of the HTR-PM nuclear power plant has significant potential for retrofitting, which can be a crucial research direction for nuclear retrofitting of coal-fired power plants.
Fast Pyrolysis of Municipal Green Waste in an Auger Reactor: Effects of Residence Time and Particle Size on the Yield and Characteristics of Produced Oil
Authors: Hasan M. M. , Rasul M. G. , Jahirul M. I. , Khan M. M. K.
Published: June 2024

The development of renewable sources for energy production has assumed a vital role in recent years, particularly with regard to the preservation of energy supplies and the environment. In this regard, municipal green waste (MGW) can be a potential renewable energy source if it is integrated with emerging technology, like pyrolysis. Therefore, this study aimed at investigating the effect of residence time and particle size on the yield and composition of oil derived from MGW using fast pyrolysis in an auger reactor. The residence time and particle size were varied from 1 min to 4 min and 1 mm to 10 mm, respectively, while keeping the temperature constant at 500 °C. At a residence time of 3 min, a 2 mm particle size provided the highest bio-oil yield (39.86%). At this experimental setting, biochar yield of 27.16% and syngas yield of 32.98% were obtained. The characterization of produced bio-oil revealed that a total of nine functional groups were present in the bio-oil. The phenols were highest in amount, followed by aromatics and ketones. The increase in residence time decreased the amount of acidic compounds present in the bio-oil. The water content was decreased by ~11% and the calorific value was increased by ~6% with the increase in particle size from 1 mm to 10 mm. Other properties, such as viscosity, density, cetane number, and flash point, did not change significantly with the change in experimental conditions. With a calorific value of 25+ MJ/kg, although the bio-oil produced from MGW can be used for heating (such as in boilers and furnaces), the use of MGW bio-oil in engines requires appropriate upgrading through procedures like hydrodeoxygenation, catalytic cracking, esterification, etc.
Thermal Evaluation of the Initial Concept 3.X Vehicle at Mach 7
Authors: Dhanagopal Abinayaa , Strasser Nathan S. , Andrade Angelina , Posladek Kevin R. , Hoffman Eugene N. A. , Combs Christopher S.
Published: June 2024

High-speed global surface temperature distributions and heat flux measurements on the Initial Concept 3.X vehicle (IC3X) model were investigated at the UTSA Mach 7 wind tunnel, examining angles of attack of 0° and 5° at a freestream unit Reynolds number (Re) ~7 × 106 m−1. A ruthenium-based, fast-responding, temperature-sensitive paint (fast-TSP) prepared in-house was applied to a 7.1% scale model of the vehicle. Static calibration was performed to convert the intensity measurements into surface temperature values. The surface temperatures and derived heat flux fields conformed to the predicted trends, which was corroborated by Schlieren flow visualization. Notably, the average surface temperature variation was identified to range from 6 to 34 K at a 0° angle of attack and from 11 to 44 K at a 5° angle of attack, with the most pronounced gradient detected at the stagnation point. Additional measurements provided a detailed thermal assessment of the model, including estimations of the stagnation point heat flux, the convective heat transfer coefficient, and the modified Stanton number. Statistical and time series analyses of the data collected revealed the absence of prevailing unsteady phenomena, suggesting that the tested design geometry is well suited for hypersonic flight applications. These experimental outcomes not only shed light on the aerothermodynamics experienced during high-speed flight but also underscore the effectiveness of fast-TSP in capturing both quantitative and qualitative thermal data.
Methods of Rut Depth Measurements on Forwarder Trails in Lowland Forest
Authors: Lovrinčević Mihael , Papa Ivica , Popović Maja , Janeš David , Poršinsky Tomislav , Pentek Tibor , Đuka Andreja
Published: June 2024

Rutting measurements are a significant part of scientific research on the impact of forest vehicles on the forest soils and damage to the forest transport infrastructure. Although photogrammetric methods of measurement or measurements based on LiDAR (light detection and ranging) data are increasingly being used for rutting measurements, the previous research conducted using these methods indicated the challenge of recording water-filled ruts. For this reason, it is necessary to define a reliable method of rutting field measurement in lowland forest stands characterized by a high level of groundwater that fills the ruts shortly after the passage of forest vehicles. This research analyzed the measurement accuracy using a total station and a GNSS RTK device with a CROPOS correction base in relation to the measuring rod that represented the reference method. Based on recorded and processed data, ruts are displayed in two ways: as net and as gross value of rut depth. The analysis of net rutting revealed a statistically significant difference between the calculated rut depths based on measurements with a GNSS RTK device and other methods. On average, the net rutting measured by the GNSS RTK device was 2.86 cm smaller than that of the reference method. When calculating the gross rutting, which consisted of the net rut depth and the bulge height, no statistically significant difference was found between the measurement methods used. Based on this result, the bulge height was also analyzed, and showed a statistically significant difference between the data recorded by the GNSS RTK device and other methods. It can be concluded that measuring the depth of ruts with a total station gives accurate data and represents the optimal modern field measurement method for the same or similar terrain conditions. In contrast, the GNSS RTK device, which constantly gives higher elevation points, can be used to measure gross rutting.
Optimizing Hardwood Lignin Precipitation from Kraft Black Liquor: A Study of Temperature and pH Effects
Authors: Nadányi Richard , Zinovyev Grigory , Majerčiak Matúš , Štosel Martin , Jablonský Michal , Ház Aleš
Published: June 2024

Lignin, a complex and heterogeneous biopolymer derived from wood, holds immense potential as a sustainable feedstock for various industrial applications. Kraft pulping, a widely employed process in the paper industry, generates black liquor containing lignin along with other organic and inorganic compounds. The precipitation of lignin from black liquor offers an opportunity for valorization, contributing to the circular economy and reducing the environmental impact. Although the precipitation process of softwood lignin is extensively documented and outlined in the existing literature, the identical process originating from hardwood-derived black liquor poses challenges attributed to the distinct composition of hardwood. This study systematically investigates the individual and combined influences of temperature and pH on the precipitation of hardwood lignin from kraft black liquor, utilizing a factorial design to evaluate lignin functional characteristics. The characterization of the precipitated lignin was performed using various analytical techniques, mainly NIR, elemental composition, UV-VIS, and calorimetry. The results reveal remarkable interactions between temperature and pH, indicating their synergistic effects on lignin precipitation. The optimal conditions for hardwood lignin precipitation were identified and successfully upscaled during piloting experiments conducted under industrial conditions. This research provides valuable insights into the fundamental factors governing hardwood lignin precipitation from kraft black liquor and offers a basis for the development of efficient and sustainable lignin recovery processes in the pulp and paper industry.
A Novel Finite Element-Based Method for Predicting the Permeability of Heterogeneous and Anisotropic Porous Microstructures
Authors: Mulye Paris , Syerko Elena , Binetruy Christophe , Leygue Adrien
Published: June 2024

Permeability is a fundamental property of porous media. It quantifies the ease with which a fluid can flow under the effect of a pressure gradient in a network of connected pores. Porous materials can be natural, such as soil and rocks, or synthetic, such as a densified network of fibres or open-cell foams. The measurement of permeability is difficult and time-consuming in heterogeneous and anisotropic porous media; thus, a numerical approach based on the calculation of the tensor components on a 3D image of the material can be very advantageous. For this type of microstructure, it is important to perform calculations on large samples using boundary conditions that do not suppress the transverse flows that occur when flow is forced out of the principal directions. Since these are not necessarily known in complex media, the permeability determination method must not introduce bias by generating non-physical flows. A new finite element-based method proposed in this study allows us to solve very high-dimensional flow problems while limiting the biases associated with boundary conditions and the small size of the numerical samples addressed. This method includes a new boundary condition, full permeability tensor identification based on the multiscale homogenization approach, and an optimized solver to handle flow problems with a large number of degrees of freedom. The method is first validated against academic test cases and against the results of a recent permeability benchmark exercise. The results underline the suitability of the proposed approach for heterogeneous and anisotropic microstructures.
Numerical and Experimental Analysis of Buckling and Post-Buckling Behaviour of TWCFS Lipped Channel Section Members Subjected to Eccentric Compression
Authors: Jankowski Jacek , Kotełko Maria , Ungureanu Viorel
Published: June 2024

The paper presents a static analysis of the buckling and post-buckling state of thin-walled cold-formed steel (TWCFS) lipped channel section beam-columns subjected to eccentric compression. Eccentricity is taken into consideration relative to both major and minor principal axes. An analytical–numerical solution to the buckling and post-buckling problems is described. The solution is based on the theory of thin plates. Equations of equilibrium of section walls are derived from the principle of stationary energy. Then, to solve the problem, the finite difference (FDM) and Newton–Raphson methods are applied. Linear (buckling) and nonlinear (post-buckling) analyses are performed. As a result, pre- and post-buckling equilibrium paths are determined. Comparisons of the obtained numerical results, FE simulation results, and experimental test results are carried out and presented in comparative load-shortening diagrams. Additionally, a comparison of the buckling forces and buckling modes obtained from theoretical analysis and experiments is presented.
The Influence of Spray Cooling Parameters on Workpiece Residual Stress of Turning GH4169
Authors: Feng Xinmin , Liu Jinrong , Hu Jingshu , Liu Zhiwei
Published: June 2024

To effectively reduce residual stresses in GH4169 workpieces, thus enhancing fatigue strength and operational lifespan, this study investigates the influence of spray cooling parameters on surface residual stresses during GH4169 turning in spray cooling conditions, utilizing both simulation and experimental approaches. A simulation model of residual stresses was established using finite element analysis when GH4169 was cut in spray cooling. The effects of spray pressure and flow rate on residual tensile stresses were analyzed. The analysis reveals that with increasing spray pressure, residual tensile stresses show a decreasing trend, gradually stabilizing. Conversely, with an increasing spray flow rate, residual tensile stresses initially decrease and then increase. The turning experiments of GH4169 were conducted under different spray parameters. After the experiment, the workpiece was sectioned and analyzed for residual stresses using X-ray diffraction instrumentation. The value residual stress measured closely matched those of simulation, with a relative error within 6%, validating the accuracy of the simulation model and confirming the appropriateness of parameter settings. These results contribute to the further promotion of spray cooling technology and facilitate the rational selection of spray parameters.
Fabrication of Strontium Molybdate with Functionalized Carbon Nanotubes for Electrochemical Determination of Antipyretic Drug-Acetaminophen
Authors: Khandagale Dhanashri D. , Wang Sea-Fue
Published: June 2024

In recent years, there has been a significant interest in the advancement of electrochemical sensing platforms to detect antipyretic drugs with high sensitivity and selectivity. The electrochemical determination of acetaminophen (PCT) was studied with strontium molybdate with a functionalized carbon nanotube (SrMoO4@f-CNF) nanocomposite. The SrMoO4@f-CNF nanocomposite was produced by a facial hydrothermal followed by sonochemical treatment, resulting in a significant enhancement in the PCT determination. The sonochemical process was applied to incorporate SrMoO4 nanoparticles over f-CNF, enabling a network-like structure. Moreover, the produced SrMoO4@f-CNF composite structural, morphological, and spectroscopic properties were confirmed with XRD, TEM, and XPS characterizations. The synergistic effect between SrMoO4 and f-CNF contributes to the lowering of the charge transfer resistance (Rct=85 Ω·cm2), a redox potential of Epc=0.15 V and Epa=0.30 V (vs. Ag/AgCl), and a significant limit of detection (1.2 nM) with a wide response range of 0.01–28.48 µM towards the PCT determination. The proposed SrMoO4@f-CNF sensor was studied with differential pulse voltammetry (DPV) and cyclic voltammetry (CV) techniques and demonstrated remarkable electrochemical properties with a good recovery range in real-sample analysis.
Preparation and Modeling of Graphene Bubbles to Obtain Strain-Induced Pseudomagnetic Fields
Authors: Yu Chuanli , Cao Jiacong , Zhu Shuze , Dai Zhaohe
Published: June 2024

It has been both theoretically predicted and experimentally demonstrated that strain can effectively modulate the electronic states of graphene sheets through the creation of a pseudomagnetic field (PMF). Pressurizing graphene sheets into bubble-like structures has been considered a viable approach for the strain engineering of PMFs. However, the bubbling technique currently faces limitations such as long manufacturing time, low durability, and challenges in precise control over the size and shape of the pressurized bubble. Here, we propose a rapid bubbling method based on an oxygen plasma chemical reaction to achieve rapid induction of out-of-plane deflections and in-plane strains in graphene sheets. We introduce a numerical scheme capable of accurately resolving the strain field and resulting PMFs within the pressurized graphene bubbles, even in cases where the bubble shape deviates from perfect spherical symmetry. The results provide not only insights into the strain engineering of PMFs in graphene but also a platform that may facilitate the exploration of the strain-mediated electronic behaviors of a variety of other 2D materials.
Structural Analysis and Adsorption Studies of (PbO, MgO) Metal Oxide Nanocomposites for Efficient Methylene Blue Dye Removal from Water
Authors: Helali Saloua , Rashad Mohamed , Ben Mabrouk Anouar , Alanazi Munirah A. A. , Mustafa Manahil S.
Published: June 2024

In the present work, magnesium oxide (MgO) and lead oxide (PbO) nanoparticles were prepared by the co-precipitation method. Their structural parameters and morphology were investigated using XRD, HRTEM, and FTIR. The formation of the phases was seen to have small average crystallite sizes and an orthorhombic crystal structure for both MgO and PbO nanoparticles. The results of HR-TEM showed irregularly shaped nanoparticles: quasi-spherical or rod-like shapes and spherical-like shapes for MgO and PbO nanoparticles, respectively. The produced nanoparticles’ size using X-ray diffraction analysis was found to be 17 nm and 41 nm for MgO and PbO nanoparticles, respectively. On the other hand, it was observed from the calculations that the optical band gap obeys an indirect allowed transition. The calculated values of the band gap were 4.52 and 4.28 eV for MgO and PbO NPs, respectively. The MB was extracted from the wastewater using the prepared composites via absorption. Using a variety of kinetic models, the adsorptions were examined. Out of all the particles, it was discovered that the composites were best. Furthermore, of the models currently under consideration, the pseudo-second-order model best fit the degradation mechanism. The resultant composites could be beneficial for degrading specific organic dyes for water purification, as well as applications needing a wider optical band gap.
Study on the Bending–Shear Properties of Concrete-Filled Circular Carbon Fibre Reinforced Plastic Steel Tubes
Authors: Wang Qingli , Qin Haiyu , Peng Kuan
Published: June 2024

In order to study the bending–shear performance of CFRP concrete-filled steel tubes, static tests were conducted on 15 circular concrete-filled CFRP steel tube bending–shear specimens. For all specimens, Ds was 120 mm, ts was 2 mm, and ml was 1. The shear displacement (V-Δ) curve of the specimen and the collaborative work between the steel tube and CFRP are discussed. ABAQUS was applied to simulate the V-Δ curve and failure mode of the specimen. We explored the effects of CFRP layers, material strength, the steel ratio, and the shear span ratio on the bending–shear performance of components. The experimental results show that a steel tube and CFRP can work together. As the shear span ratio increased, the bearing capacity and stiffness of the specimen decreased. An increase in the number of transverse CFRP layers could improve the bearing capacity of the specimen, but it had no significant effect on the stiffness. Calculating the elastic stage stiffness and bearing capacity of 15 short columns of test and FE curves revealed an average error of 6.71% and a mean square error of 0.83 for the elastic stage stiffness. The simulation results of the established finite element model are in good agreement with the experimental results. The average error of the bearing capacity was 3.88%, with a mean square error of 0.94. Based on experimental and finite element results, the moment shear correlation equation for concrete-filled CFRP steel tube bending–shear members is presented.
New-Generation Materials for Hydrogen Storage in Medium-Entropy Alloys
Authors: Varcholová Dagmara , Kušnírová Katarína , Oroszová Lenka , Möllmer Jens , Lange Marcus , Gáborová Katarína , Buľko Branislav , Demeter Peter , Saksl Karel
Published: June 2024

This study presents the design, preparation, and characterization of thirty new medium-entropy alloys (MEAs) in three systems: Al-Ti-Nb-Zr, Al-Ti-Nb-V, and Al-Ti-Nb-Hf. The hardness of the alloys ranged from 320 to 800 HV0.3. Among the alloys studied, Al15Ti40Nb30Zr15 exhibited the highest-reversible hydrogen storage capacity (1.03 wt.%), with an H/M value of 0.68, comparable to LaNi5, but with a reduced density (5.11 g·cm−3) and without rare earth elements. This study further reveals a strong correlation between hardness and hydrogen absorption/desorption; higher hardness is responsible for reduced hydrogen uptake. This finding highlights the interplay between a material’s properties and hydrogen storage behavior in MEAs, and has implications for the development of efficient hydrogen storage materials.