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2025
Heat transfer enhancement from tube bank in cross flow with air can be
achieved for energy saving by enhancing the flow turbulence nature. Adding
splitter plates (SPs) to the tubes? trailing edges, besides, increasing the
heat transfer surface?s roughness are proposed options to enhance the flow
turbulence. However, few literatures are available to discuss this,
moreover, almost all available Computational Fluid Dynamics (CFD) models
employ Reynolds-Averaged Navier-Stokes (RANS) turbulence models and away
from using Large Eddy Simulation (LES). Accordingly, this work was presented
to compare the employing of RANS and LES turbulence models for such problems
at low Reynolds numbers. Toward this objective, a complete 3D CFD model
consisting of seven rows of tubes in flow direction is developed without
using any symmetrical boundary conditions. The present study includes the
impact of the Remax range (500 to 4500), for three surface relative
roughnesses: ks/D of 0, 0.01, and 0.02. The local turbulence and heat
transfer characteristics are discussed. The findings confirmed that the two
proposed options for heat transfer enhancement succeeded in doubling it. LES
is superior to RANS models in resolving a wide spectrum scale of flow
eddies. The results are useful in designing more efficient heat exchangers,
especially at low Reynolds number.- Book : (00)
- Pub. Date : 2025
- Page : pp.26-26
- Keyword :
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2025
In this paper, the numerical and analytical treatment for the heat irreversibility of thermal radiation and Ohmic heating on Williamson fluid problem is investigated with various physical parameters and the new initial conditions which poses arbitrary constants. The governing equations are transformed into dimensionless formulas, the ordinary differential equations obtained are then solved using the BVP4c and the differential transform method (DTM) . The heat irreversibility analysis is achieved by substituting the obtained results into entropy generation and Bejan number expressions. The results of numerical and analytical solutions for various parameters are compared. Fluid motion is reduced by the increasing values of thermal radiation parameter, the magnetic parameter and Reynolds number. In addition, every flow parameter investigated increases fluid temperature exception thermal radiation parameter. Entropy generation is also improved at the upper wall of the channel.- Book : ()
- Pub. Date : 2025
- Page : pp.293-316
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2025
The second law of thermodynamics investigates the quality of energy, or in other words exergy, described as the maximum useful to the dead-state work. The objective of this paper is to investigate the energy and exergy flows in a crop plant system in order to identify the dominant flows and parameters (e.g., temperature) affecting crop plant development. The need for energy and exergy analyses arises from the hypothesis that crop stress can be detected via surface temperature measurements, as explained by the exergy destruction principle (EDP). Based on the proposed energy model, it is observed that radiation and transpiration terms govern all other terms. In addition, as a result of exergy analysis, it is observed that solar exergy governs all input and output terms. The results obtained from this study support the hypothesis that crop surface temperature can be utilized as an indicator to detect crop stress.- Book : 5(1)
- Pub. Date : 2025
- Page : pp.3-3
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2025
The domains of lightning electromagnetic pulse (LEMP) fields are classified as “near-field,” “intermediate-field,” and “far-field” based on qualitative descriptions. However, the systematic quantitative classification of LEMP fields is yet to be reported. This study characterized the wave impedance of lightning electromagnetic pulse (WILEMP) to solve this problem. The components and field domain distribution ranges of LEMP were analyzed by varying the WILEMP and the distance between the observation point and radiation source (r). The changes in the WILEMP with r under the influence of different factors were calculated using the finite-difference time-domain (FDTD) method. The results indicated that the LEMP field has high impedance. the WILEMP decreased rapidly with the increase in r when r ≤ 10 km, consistent with the characteristics of the electrostatic and induction fields (near field). The WILEMP gradually decreased and stabilized with the increase in r when r ≥ 20 km, and the value was roughly the same as the impedance of free space (377 Ω) when r = 100 km, consistent with the characteristics of radiation field (far field). The decay rate of the WILEMP was lower than that when r ≤ 10 km but higher than that when r ≥ 20 km. Finally, when 10 km < r < 20 km, the apparent transitivity was consistent with intermediate-field characteristics.- Book : 15(2)
- Pub. Date : 2025
- Page :
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2025
Coal resource extraction and utilization are essential for sustainable development and economic growth. This study integrates a pseudo-triaxial mechanical loading system with low-field nuclear magnetic resonance (NMR) to enable the preliminary visualization of coal’s pore-fracture structure (PFS) under mechanical stress. Pseudo-triaxial and cyclic loading–unloading tests were combined with real-time NMR monitoring to model porosity recovery, pore size evolution, and energy dissipation, while also calculating the fractal dimensions of pores in relation to stress. The results show that during the compaction phase, primary pores are compressed with limited recovery after unloading. In the elastic phase, both adsorption and seepage pores transform significantly, with most recovering post-unloading. After yield stress, new fractures and pores form, and unloading enhances fracture connectivity. Seepage pore porosity shows a negative exponential relationship with axial strain before yielding, and a logarithmic relationship afterward. The fractal dimension of adsorption pores decreases during compaction and increases afterward, while the fractal dimension of seepage pores decreases before yielding and increases post-yielding. These findings provide new insights into the flow patterns of methane in coal seams.- Book : 9(2)
- Pub. Date : 2025
- Page : pp.93-93
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2025
- Book : ()
- Pub. Date : 2025
- Page :
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2025
Background: The prognostic impact of internal carotid artery (ICA) invasion in nasopharyngeal cancer (NPC) patients is not well established. Thus, we conducted a retrospective study to analyze the prognostic factors for ICA invasion by NPC. Methods: This retrospective study included consecutive biopsy-proven NPC patients who received CCRT from November 2015 to December 2022 at E-Da Hospital. Patients were then classified into two groups according to ICA invasion by tumor or not. Survival was estimated by the Kaplan–Meier method with a five-year overall survival (OS) rate and five-year disease specific survival (DSS) rate. Results: A total of 191 patients with pathologically confirmed NPC were included in this study, with 54 patients in the ICA invasion group and 137 patients in the no ICA invasion group. The ICA invasion group showed a worse prognosis compared to the no ICA invasion group (p < 0.001 in OS and DSS). Patients were stratified into a poor response group and good response group. OS and DSS in the poor response group had a significant difference compared to the good response group (both p < 0.001). In multivariate analysis, NLR was an independently prognostic factor for OS (HR 2.430, 95% CI 1.040–5.678, p = 0.040 and HR 0.412, 95% CI 0.176–0.962, p = 0.040, respectively) and for DSS (HR 2.430, 95% CI 1.040–5.678, p = 0.040 and HR 0.412, 95% CI 0.176–0.962, p = 0.040, respectively). Conclusions: Locally advanced NPC patients with ICA invasion have a miserable outcome and NLR represents a significant prognostic factor that impacts treatment decisions and survival.- Book : 17(3)
- Pub. Date : 2025
- Page : pp.488-488
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2025
Tetraploidy is a condition in which the entire set of chromosomes doubles, most often due to errors during cell division. Tetraploidy can lead to genomic instability and significant consequences, in particular metastasis and treatment failure in tumours, including radiotherapy. The development of new strategies to sensitise these cells to treatment is of great importance. In our study, we investigated the in vitro combination of chemical treatment with the kinase inhibitor SP600125 and irradiation on diploid versus metastatic tetraploid RKO colon cancer clones. We assessed mitochondrial transmembrane potential, cell cycle and subG1 population by flow cytometry and performed clonogenic assays to evaluate cell sensitivity. We found that the combination overcomes irradiation resistance in metastatic tetraploid clones. To identify the main pathway involved in cell sensitivity, we screened the Harvard Medical School KINOMEscan library and performed a gene ontology biological process analysis. We found that the major kinases inhibited by SP600125 were ANKK1, BIKE, IKKA, JNK1, MP2K3, MP2K4, MKNK2, MYLK, PLK4, RPS6KA4(Kin,Dom,1), MYLK4 and TTK, and the pathways involved in clone sensitivity were DNA damage repair, radiation resistance and apoptosis, through JNK pathway inhibition. Finally, our main finding was that combined treatment with SP600125 and radiotherapy reduced the resistance of metastatic tetraploid cells to treatment, essentially by inhibiting the JNK pathway. This result supports a promising anti-cancer strategy to overcome the resistance of tetraploid cancer cells to irradiation.- Book : 26(3)
- Pub. Date : 2025
- Page : pp.1209-1209
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2025
Abstract
The ctenophore Mnemiopsis leidyi is native to the Atlantic coasts of the Americas and is considered a threat to biodiversity and food webs in recipient ecosystems. Most of these invasive ctenophores perish during the cold winter in temperate northern European waters (North and Baltic Seas) but spread again every summer/autumn. We collected ctenophores from the southern North Sea, inner Danish waters, and western Baltic Sea in 2017 and 2018, and sequenced genomic DNA obtained from tissue samples. We obtained sequences of internal transcribed spacer (ITS) 1 and 2, and the intervening 5.8S fragment and partial fragments of the flanking 18S rRNA and 28S rRNA genes from nuclear DNA. Excluding the rRNA regions and focussing on only the two ITS sequences, we compared with ITS sequences archived in databases from specimens in its native (Northwest Atlantic) and other invaded habitats (Caspian Sea, Mediterranean Sea, central-western Atlantic Ocean). The comparison revealed no significant difference in genetic variation among temperate northern European sampling locations but showed variation when compared with native and other invaded habitats. No significant genetic difference was identified between specimens collected in the temperate northern European waters for two consecutive years. The very low interregional and interannual genetic variations in M. leidyi specimens in the Northeast Atlantic are consistent with the presence of one single panmictic population in northern European waters and with the hypothesis, also suggested in previous studies, that annual dispersal from the southeastern North Sea into the western Baltic Sea can be traced back to the same population, which most likely originates every spring from the Dutch Wadden Sea and the English Channel.- Book : 27(2)
- Pub. Date : 2025
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2025
Abstract
We discuss several properties of two families of finite-range interactions in infinite nuclear matter, aiming in particular to their isovector properties. We find that the recent parameterisations of both Gogny and Nakada provide a reasonable description of the properties of the infinite medium as well as an equation of state capable of sustaining a two solar mass neutron star. We also discuss the pairing properties in the spin-singlet channel for both families of interactions.- Book : 61(2)
- Pub. Date : 2025
- Page :
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