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Full-Text Articles in Physical Sciences and Mathematics

An Exploratory Analysis Of Automated Deception Detection For Mental Health Applications, Sayde Leya King Jun 2025

An Exploratory Analysis Of Automated Deception Detection For Mental Health Applications, Sayde Leya King

USF Tampa Graduate Theses and Dissertations

Deception in mental health settings can undermine therapeutic relationships, compromise treatment efficacy, and impact patient outcomes. Yet, research shows that mental health clinicians often perform no better than chance at detecting deceptive behavior in therapy. Automated deception detection, leveraging artificial intelligence (AI) and multimodal behavioral cues—such as eye gaze, body gestures, and facial expressions—offers a promising alternative. However, most existing research focuses on high-stakes legal contexts, limiting its applicability to mental health settings.

This dissertation addresses this gap by pursuing three key research objectives using a mixed-methods approach. First, we investigate mental health clinicians’ perspectives on AI-assisted deception detection through …


Efficient Methods And Algorithms For Analyzing Stochastic Systems, Mohammad Ahmadi Jun 2025

Efficient Methods And Algorithms For Analyzing Stochastic Systems, Mohammad Ahmadi

USF Tampa Graduate Theses and Dissertations

This dissertation addresses the challenges of stochastic analysis of safety-critical systems with biological components, where unexpected behavior can lead to catastrophic events. Two fundamental challenges hinder the analysis of such systems: their typically large or infinite state spaces, and the extreme rarity of error states of interest. While Monte Carlo simulation can analyze biochemical systems without storing the state space, accurately estimating rare event probabilities becomes computationally prohibitive. Conversely, probabilistic model checking excels at analyzing extremely low probability events but becomes impractical for systems with large or infinite state spaces due to memory constraints.This work proposes two main contributions to …


Bahadur Representations For Canonical Quantile Regression: A Correction And Extension, Stephen Portnoy Jun 2025

Bahadur Representations For Canonical Quantile Regression: A Correction And Extension, Stephen Portnoy

Mathematics and Statistics Faculty Publications and Presentations

Portnoy (2022) introduced a version of Canonical Correlation anal- ysis based on Regression Quantiles. The proof of the asymptotic convergence of the estimators contained some gaps. A new proof is developed using Bahadur representations to obtain asymptotic represen- tations for the Canonical Regression Quantile components with error uniformly Op (n-1/4 log n). These innovative representations justify approximations and automatically provide joint convergence in dis- tribution. This enables an inductive argument to obtain asymptotic results for all components. These novel Bahadur approximations may have more general application and interest.


Deliberately Queer Journal Editors' Note For Volume One, Sean Te Maulding, Mel Monier Jun 2025

Deliberately Queer Journal Editors' Note For Volume One, Sean Te Maulding, Mel Monier

Deliberately Queer Journal

No abstract provided.


Technology Manufacturing Organizations’ Strategies For Achieving Sustainability, Kate Cheney Jun 2025

Technology Manufacturing Organizations’ Strategies For Achieving Sustainability, Kate Cheney

Walden Dissertations and Doctoral Studies

Sustainability remains a challenge for technology manufacturers struggling to integrate environmental priorities into core operations. This issue is critical for technology manufacturing managers who must embed sustainability into organizational systems and decision-making processes to meet rising expectations from regulators, investors, and consumers. Grounded in transformational leadership theory, the purpose of this qualitative pragmatic inquiry study is to identify and explore effective strategies used by technology manufacturing managers in the western region of the United States. The data collected from seven semistructured interviews were analyzed using thematic analysis. The five themes that emerged were (a) leadership and company culture, (b) collaboration, …


Isotopic Fingerprints Of The Coastal Margins: Tracing Dissolved Iron Sources From Land To Sea, Hannah R. Hunt Jun 2025

Isotopic Fingerprints Of The Coastal Margins: Tracing Dissolved Iron Sources From Land To Sea, Hannah R. Hunt

USF Tampa Graduate Theses and Dissertations

Dissolved iron (dFe) is an essential micronutrient for sustaining life in the surface ocean. Nearly four decades of research dedicated to understanding sources, cycling and biogeochemical modifications of Fe sources in the global oceans has generated a significant body of research supporting the idea that the concentration of Fe in the surface ocean exerts significant controls on primary production and carbon uptake in the surface ocean. Creation of the GEOTRACES program greatly increased the spatial and temporal resolution of high-quality trace element and trace element isotope data revealing new insights into the global Fe cycle, especially through the use of …


Applications Of Contracting Self-Similar Groups To Cryptography And Scale Groups, Arsalan Akram Malik Jun 2025

Applications Of Contracting Self-Similar Groups To Cryptography And Scale Groups, Arsalan Akram Malik

USF Tampa Graduate Theses and Dissertations

Given their peculiar properties, self-similar groups are of great interest both from applications and theoretical standpoints. In this work we study the scope of their applications in post-quantum cryptography and in constructing scale groups via lifting maps.

We propose self-similar contracting groups as a platform for cryptographic schemes based on simultaneous conjugacy search problem (SCSP). This class of groups admits fast polynomial-time algorithms for the word problem and element multiplication that can be used for effective encryption and decryption of messages. It contains extraordinary examples like the Grigorchuk group, which is known to be non-linear, thus making some of existing …


Enhancement Of Phenolic, Flavonoid, And Biological Activi-Ties In Fermented Pea (Pisum Sativum) Extracts Via Frac-Tionation, Anastasia Fitria Devi, Euis Filailla, Setyani Budiari, Hani Mulyani, Nina Artanti Jun 2025

Enhancement Of Phenolic, Flavonoid, And Biological Activi-Ties In Fermented Pea (Pisum Sativum) Extracts Via Frac-Tionation, Anastasia Fitria Devi, Euis Filailla, Setyani Budiari, Hani Mulyani, Nina Artanti

Karbala International Journal of Modern Science

In this study, peas were fermented for 24 h using either Rhizopus oligosporus or Aspergillus oryzae. The resulting fermented peas, along with unfermented peas, were extracted using either methanol or water. The methanol extracts showed greater improvements following fermentation compared to the water extracts, as shown by the IC50 values, which progressed from >500 to ≤200 µg/mL, as determined via the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) method. Consequently, further fractionations focused on the methanol extracts of the fermented peas. Six bands were resolved on thin-layer chromatography plates for each extract. Their positions demonstrated significant effects (p < 0.05) on bioactivity. The bottom band (i.e., Band 1) exhibited approximately 70% inhibition, as determined via the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and 35% inhibition according to the ABTS method, while the other bands displayed lower to negligible inhibition. Band 5 displayed 85–97% cytotoxicity, while Band 1 did not show any cytotoxicity. The total phenolic content (TPC) of Band 1 and the total flavonoid content (TFC) of Band 6 increased 4.4- and 8.9-fold, respectively, compared to those of the unfractionated extracts. Furthermore, a correlation analysis revealed a strong correlation between TFC and the three observed bioactivities. The different cultures significantly (p < 0.05) affected the antioxidant activity of either the fermented pea extracts or the resulting bands, as determined via the DPPH method. These results indicated that fermentation enhanced the antioxidant activity of peas. Subsequent fractionations separated and concentrated compounds from the fermented peas, improving the bioactivities, TPC, and TFC of the resulting fractions.


Synthesis Of Gold Nanoparticles Using Hordeum Vulgare Leaf Extract And Their Antibacterial Activity, Mohamed M. Sehree, Shakir Ghazi Gergees, Pakhshan A. Hassan Jun 2025

Synthesis Of Gold Nanoparticles Using Hordeum Vulgare Leaf Extract And Their Antibacterial Activity, Mohamed M. Sehree, Shakir Ghazi Gergees, Pakhshan A. Hassan

Karbala International Journal of Modern Science

Plant extracts and gold nanoparticles are promising alternatives for combating antibiotic resistance in light of the increasing bacterial resistance. Leaf extract of barley was used to synthesize gold nanoparticles (AuNPs). Barley gold nanoparticles (BL-AuNPs) were produced by adjusting some reaction parameters. These BL-AuNPs were characterized through employing the UV-visible spectroscopy technique, the scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), and energy dispersive X-ray spectroscopy (EDX). BL-AuNPs were tested for antibacterial efficacy against two strains of Gram-negative bacteria, clinically isolated and considered as multidrug-resistant pathogens, Acinetobacter baumannii and Salmonella typhi. The antimicrobial efficiency of the compounds was evaluated …


The Impact Of Microplastics On Water Quality, Heavy Metals, And Health Risks In Bioflocbased Tilapia Farming Systems, Dian Rizky Afriani, Deswati Deswati, Rahmiana Zein, Putri Ramadhani Jun 2025

The Impact Of Microplastics On Water Quality, Heavy Metals, And Health Risks In Bioflocbased Tilapia Farming Systems, Dian Rizky Afriani, Deswati Deswati, Rahmiana Zein, Putri Ramadhani

Karbala International Journal of Modern Science

Along with microplastics, pollution of heavy metals, including iron (Fe), zinc (Zn), and copper (Cu), in freshwater ecosystems poses a serious environmental threat that can adversely affect human health. This study investigates the use of biofloc technology to reduce microplastic and heavy metal contamination while improving water quality. By utilizing microbial aggregates that capture microplastic and heavy metal particles through flocculation and biosorption processes, four experimental treatments were applied, i.e.: A (without biofloc and microplastics); B (with biofloc, without microplastics); C (with biofloc and low-density polyethylene microplastics); and D (with biofloc and high-density polyethylene microplastics). The results indicate that fish …


On Programmatic Aspects Of The Universality, Parameter, And Recursion Theorems Of Classical Computability, Vladimir A. Kulyukin Jun 2025

On Programmatic Aspects Of The Universality, Parameter, And Recursion Theorems Of Classical Computability, Vladimir A. Kulyukin

Computer Science Faculty and Staff Publications

The Universality, Parameter, and Recursion Theorems are three foundational results of classical computability theory. We show how these theorems can be programmatically illustrated and partially validated in Lisp. Our programs can be used as supplementary materials to texts on theoretical computer science, mathematical logic, or metamathematics.


Synthesis Of Carboxymethyl Cellulose From Nypa Fruticans For Coating Metformin On Zn-Based Metal-Organic Framework Nanohybrid As A Bionanocomposite Drug Delivery System, Delviani Delviani, Viola Giary Rizkillah Maharani, Putri Nur Shadrina, Tri Warni, Regina Wan Azizah, Indra Lasmana Tarigan, Madyawati Latief Jun 2025

Synthesis Of Carboxymethyl Cellulose From Nypa Fruticans For Coating Metformin On Zn-Based Metal-Organic Framework Nanohybrid As A Bionanocomposite Drug Delivery System, Delviani Delviani, Viola Giary Rizkillah Maharani, Putri Nur Shadrina, Tri Warni, Regina Wan Azizah, Indra Lasmana Tarigan, Madyawati Latief

Makara Journal of Science

Diabetes is a common and rapidly spreading disease that affects 6.6% of the world’s population. Metformin hydrochloride (HCl) is an effective oral pharmacological treatment for type 2 diabetes mellitus (T2DM) patients because of its capability to reduce glucose levels and the risk of hypoglycaemia. However, gastrointestinal sensitivities to this drug can cause diarrhoea, nausea, vomiting and stomach ache. An alternative is controlled release technology by coating metformin with carboxymethyl cellulose (CMC) and zinc-metal-organic framework (Zn-MOF) through the encapsulation method. Therefore, this study aimed to coat metformin formulations using CMC in a Zn-MOF to control release into the body and minimise …


Removal Of Heavy Metals From Motorcycle Washing Wastewater Using A Zeolite-Embedded Sheet, Noverita Dian Takarina, Hanies Ambarsari, Sekar Arum Pramudyawardhani, Maria Fatima Niken Kris Rahmawati, Erni Johan, Naoto Matsue, Mohammad Afdhal Adidharma Jun 2025

Removal Of Heavy Metals From Motorcycle Washing Wastewater Using A Zeolite-Embedded Sheet, Noverita Dian Takarina, Hanies Ambarsari, Sekar Arum Pramudyawardhani, Maria Fatima Niken Kris Rahmawati, Erni Johan, Naoto Matsue, Mohammad Afdhal Adidharma

Makara Journal of Science

The increased use of motorcycles for transportation has heightened environmental challenges related to their washing, particularly the discharge of untreated wastewater containing heavy metals, such as copper (Cu) and lead (Pb), into drainage systems. This study explored the effectiveness of zeolite-embedded sheets (ZESs) in the removal of these pollutants from motorcycle washing wastewater. ZESs were prepared through treatment of nonwoven sheets with Linder Type A (LTA Zeolite) powder and heat treatment, washing, and drying. Characterization was performed via scanning electron microscopy with energy-dispersive X-ray spectroscopy, and Fourier transform infrared spectroscopy. Over a 60 min adsorption period, the ZES achieved removal …


Geochemical Nature Of The Geothermal Water From Lanzhou Basin: Implications For The Genesis Of Shallow Helium-Bearing Fluids, Tang Jianzhou, Wang Shuangming, Zhang Zhicheng, Li Ke, Li Changpeng Jun 2025

Geochemical Nature Of The Geothermal Water From Lanzhou Basin: Implications For The Genesis Of Shallow Helium-Bearing Fluids, Tang Jianzhou, Wang Shuangming, Zhang Zhicheng, Li Ke, Li Changpeng

Coal Geology & Exploration

Objective and Methods Investigations on the geochemical nature of geothermal water are vital to the comprehension of the origin of helium-rich fluids in shallow basins. To address this issue, this paper reports the results of the chemical analysis, H-O isotopes and 14C ages from geothermal water and soluble gas components from the well BY-1 in Lanzhou Basin, northeastern margin of Qinghai Tibet Plateau. Chemical analysis of geothermal water samples reveals that the chemical type of geothermal water is NaCl. The show δD value of –78‰, high δ18O value (–8.7‰), low 3H value (<0.4TU), and old 14C …


Prediction Of Geological And Engineering Integrated Sweet Spots Of Deep Coalbed Methane, Chen Zhengrong, Liu Wei, Zhu Xueshen, Tian Yongjing, Xie Xin Jun 2025

Prediction Of Geological And Engineering Integrated Sweet Spots Of Deep Coalbed Methane, Chen Zhengrong, Liu Wei, Zhu Xueshen, Tian Yongjing, Xie Xin

Coal Geology & Exploration

Objective Deep coalbed methane (CBM) has emerged as a hot topic in CBM resource development. However, deep CBM has characteristics such as great burial depths, complex stress environments, and strong reservoir heterogeneity, which seriously restrict sweet spot prediction and accurate well location deployment in its large-scale exploitation. Methods This study investigated a deep CBM field along the eastern margin of the Ordos Basin. Using sonic, density, and caliper logging, this study developed a coal structure index model for deep coals. By introducing the coal structure index based on the coal structure differences in deep coal seams and combining factors including …


Impacts Of Metakaolin And Fly Ash On The Performance Of Cement-Based Grouting Materials In Anchoring Engineering, Cheng Zhiyuan, Yang Junpeng, Xue Wei, Wei Daidong, Wang Yimin Jun 2025

Impacts Of Metakaolin And Fly Ash On The Performance Of Cement-Based Grouting Materials In Anchoring Engineering, Cheng Zhiyuan, Yang Junpeng, Xue Wei, Wei Daidong, Wang Yimin

Coal Geology & Exploration

Objective The filling of grouting materials plays a significant role in ensuring the performance of anchoring structures. This study aims to further enhance the fluidity of grouting materials, reduce their dry shrinkage in the curing process, and ensure complete filling. This will help improve the bonding property between the anchoring body and the rock and soil mass to be reinforced. Methods Using cement as the primary material, as well as fly ash and metakaolin as admixtures, this study designed and prepared 20 groups of binary and ternary mixtures and one control group. Through tests of the fluidity, bleeding ratios, and …


Diffusion Mechanisms Of Coal-Measure Helium And Their Implications For Helium Accumulation: A Case Study Of The Taiyuan Formation, Northern Qinshui Basin, China, Ma Yong, Xin Zhiyuan, Chen Jianfa, Li Yuhong, Zhang Xiutao, Jiang Haojie, Chen Zeya Jun 2025

Diffusion Mechanisms Of Coal-Measure Helium And Their Implications For Helium Accumulation: A Case Study Of The Taiyuan Formation, Northern Qinshui Basin, China, Ma Yong, Xin Zhiyuan, Chen Jianfa, Li Yuhong, Zhang Xiutao, Jiang Haojie, Chen Zeya

Coal Geology & Exploration

Objective The global helium-rich gas reservoirs are dominated by conventional natural gas reservoirs. In recent years, helium-bearing natural gas has been discovered in the Carboniferous-Permian coal measures in the Ordos Basin and surrounding regions, revealing the resource potential of coal-measure helium. However, there is almost a total lack of studies on mechanisms underlying the diffusion and migration of coal-measure helium. This severely restricts further research on the accumulation patterns of coal-measure helium.Methods This study investigated a coal seam in the Taiyuan Formation in the northern Qinshui Basin and mudstones in the coal seam roof. Using physical diffusion experiments on …


Physical Simulation Experiments On Competitive Dissolution Of Helium In Helium-Containing To Helium-Rich Gas Reservoirs, Zou Yi, Luo Qingyong, Chen Jianfa, Zou Huayao, Du Tao, Liu Xiaoqiang, Cai Xinyong, Yu Chengming, Fang Zilong Jun 2025

Physical Simulation Experiments On Competitive Dissolution Of Helium In Helium-Containing To Helium-Rich Gas Reservoirs, Zou Yi, Luo Qingyong, Chen Jianfa, Zou Huayao, Du Tao, Liu Xiaoqiang, Cai Xinyong, Yu Chengming, Fang Zilong

Coal Geology & Exploration

Background and Purpose Helium is widely applied in high-tech and scientific research fields due to its unique physicochemical properties. Formation water plays a key role in helium migration and enrichment. Typically, in the form of dissolved gas, helium is transported in pores or fractures by formation water. When helium-rich fluids migrate to shallow natural gas reservoirs, helium will experience dissolution and desorption exchange with other gases. This process is affected by formation temperature, pressure, and water salinity, as well as the competitive dissolution between helium and other gases. However, there is a lack of studies on the mechanisms underlying the …


Backfill-Strip Mining And Co2 Mineralization Sequestration In Coal Mine Goaves: A Synergetic Method And Its Key Technologies, Zhu Mengbo, Liu Lang, Wang Shuangming, Wei Baoning, Rong Ruoyu, Zhang Wenzhong, Zhuang Dengdeng, Jia Qifeng Jun 2025

Backfill-Strip Mining And Co2 Mineralization Sequestration In Coal Mine Goaves: A Synergetic Method And Its Key Technologies, Zhu Mengbo, Liu Lang, Wang Shuangming, Wei Baoning, Rong Ruoyu, Zhang Wenzhong, Zhuang Dengdeng, Jia Qifeng

Coal Geology & Exploration

Objective Coals serve as both the cornerstone of China’s energy security and important industrial raw materials. However, their mining and utilization tend to cause ecological and environmental problems such as CO2 emissions, the generation of solid wastes, and land subsidence. This necessitates reforming coal mining methods to promote the green, low-carbon, and sustainable development of China’s coal industry.Methods Through the comparative analysis of the conditions of CO2 sequestration in goaves corresponding to the caving, room-and-pillar (also known as knife-pillar), and backfill mining methods, this study developed a synergetic method for backfill-strip mining and CO2 mineralization sequestration …


A Visual Positioning Method For Tunnel Boring Machines In Underground Coal Mines Based On Anchor Net Features, Zhang Xuhui, Chi Yunkai, Du Yuyang, Jiang Junying, Yang Wenjuan, Zhao Youjun, Wan Jicheng, Wang Yanqun, Tian Chenhui Jun 2025

A Visual Positioning Method For Tunnel Boring Machines In Underground Coal Mines Based On Anchor Net Features, Zhang Xuhui, Chi Yunkai, Du Yuyang, Jiang Junying, Yang Wenjuan, Zhao Youjun, Wan Jicheng, Wang Yanqun, Tian Chenhui

Coal Geology & Exploration

Background Precise positioning of tunnel boring machines (TBMs) in underground coal mines plays a fundamental role in the automated and intelligent guidance and control of fully mechanized heading face. However, traditional visual positioning methods show limited application effects in underground roadways due to their narrow and enclosed spaces, insufficient illumination, and sparse textures. This study proposed a visual positioning method for TBMs in underground coal mines based on anchor net features.Methods A three-stream depthwise separable convolutional neural network (TSCR-NET) for image enhancement was employed to estimate the reflection, illumination, and noise in images individually. Through illumination adjustment while suppressing …


Colloidal Hot-Injection Synthesis Of Cubse2 Nanocrystals: Tetragonal Chalcogenide Templates For Superionic Lithiation Pathways, Yunhao Xu, Niket Powar, Kelly Zervos, Isabella Campbell, Simran Choudhary, Layan Al-Khaled, Progna Banerjee Jun 2025

Colloidal Hot-Injection Synthesis Of Cubse2 Nanocrystals: Tetragonal Chalcogenide Templates For Superionic Lithiation Pathways, Yunhao Xu, Niket Powar, Kelly Zervos, Isabella Campbell, Simran Choudhary, Layan Al-Khaled, Progna Banerjee

Chemistry: Faculty Publications and Other Works

Copper boron selenides represent a previously unexplored class of materials with tetragonal structural symmetries and bonding chemistries potentially relevant to lithium-ion conduction. In this work, the first colloidal synthesis of nanocrystalline copper boron selenides is reported, enabling access to nanocrystals with reaction times shown as the synthetic knob to control composition and morphology. Copper boron selenide nanocrystals are synthetically designed as precursors for lithiation reactions aimed at probing structural evolution and ionic mobility pathways toward superionic conductors applicable as solid electrolytes in lithium-ion batteries. Postsynthetic lithiation studies under ambient conditions reveal a series of phase transformations and morphological changes, which …


Homework, Households, And Hurdles: The Unexpected Drivers Of Student Graduation Perceptions, Daniel Alhassan, Zahra Fatah, Priscilla Mansah Codjoe, Caroline Bena Kuno, Dorcas Ofori-Boateng Jun 2025

Homework, Households, And Hurdles: The Unexpected Drivers Of Student Graduation Perceptions, Daniel Alhassan, Zahra Fatah, Priscilla Mansah Codjoe, Caroline Bena Kuno, Dorcas Ofori-Boateng

Mathematics and Statistics Faculty Publications and Presentations

Students’ perceptions of their likelihood to graduate are important determinants of their academic engagement, yet these perceptions remain understudied. This study, which is based on the 2021 Monitoring the Future survey of 8th- and 10th-grade students in the United States, uses machine learning algorithms to identify the most important factors that influence these perceptions. Among the tested models, random forest provided the best classification performance. Using permutation-based feature importance, we identified frequent participation in schoolwork, maternal education, paternal education, and homework completion as the most important predictors of students’ graduation perceptions. These results highlight the importance of targeted and well-coordinated …


Kolmogorov–Smirnov-Based Edge Centrality Measure For Metric Graphs, Christina Durón, H. Kravitz, Moysey Brio Jun 2025

Kolmogorov–Smirnov-Based Edge Centrality Measure For Metric Graphs, Christina Durón, H. Kravitz, Moysey Brio

Mathematics and Statistics Faculty Publications and Presentations

In this work, we introduce an edge centrality measure for the Helmholtz equation on metric graphs, a particular flow network, based on spectral edge energy density. This measure identifies influential edges whose removal significantly changes the energy flow on the network, as indicated by statistically significant p-values from the two-sample Kolmogorov–Smirnov test comparing edge energy densities in the original network to those with a single edge removed. We compare the proposed measure with eight vertex centrality measures applied to a line graph representation of each metric graph, as well as with two edge centrality measures applied directly to each …


Evolution Of Wormholes Under F(R, T) Theory, The Karmarkar Condition And The Casimir Energy, Murat Metehan Türkoğlu Jun 2025

Evolution Of Wormholes Under F(R, T) Theory, The Karmarkar Condition And The Casimir Energy, Murat Metehan Türkoğlu

Turkish Journal of Physics

In this study, both the evolution of wormholes (by examining both the energy conditions and using the TOV equations) and the effects of the Karmarkar condition on the solutions obtained under certain specific cases were examined in the light of the f(R, T) gravity theory, using two f(R, T) functions predicted to describe the accelerated expansion of the universe. In this context, for the first time in the literature, a generalized shape function was obtained using the Karmarkar condition. It was observed that solutions of the type R -a12/R+a2g(T) satisfy the energy conditions (with the dominant energy condition being partially …


Circular Motion And Thermodynamic Characteristics Of Particles Around A Quintessential Nonrotating Black Hole, Indrajit Halder, Kamal Lochan Mahanta, Rakesh Ranjan Sahoo Jun 2025

Circular Motion And Thermodynamic Characteristics Of Particles Around A Quintessential Nonrotating Black Hole, Indrajit Halder, Kamal Lochan Mahanta, Rakesh Ranjan Sahoo

Turkish Journal of Physics

This paper investigates the geodesics of the Schwarzschild black hole modified with the quintessence field and modeled as a barotropic fluid with a constant equation of state derived in Boyer Lindquist coordinates with natural units G = c = 1. Hamilton–Jacobi formalization is applied to investigate the geodesics in both static and nonstatic black hole spacetime. It specifically examines the formation of bound orbits of test particles around the black hole, highlighting that these orbits result from the interplay between the gravitational pull of the black hole and a repulsive force associated with quintessence. The thermodynamic properties of a black …


Enhanced Crack Resistance Of Porous Anodic Aluminum Oxide Grown On A Tubular Substrate With The Additive Ethylene Glycol, Manogari Sianturi, Ariadne Laksmidevi Juwono, Anawati Anawati Jun 2025

Enhanced Crack Resistance Of Porous Anodic Aluminum Oxide Grown On A Tubular Substrate With The Additive Ethylene Glycol, Manogari Sianturi, Ariadne Laksmidevi Juwono, Anawati Anawati

Makara Journal of Science

The growth of a porous anodic aluminum oxide (PAAO) layer with fewer cracks on a tubular substrate is quite challenging. The PAAO layer on a curved surface grows slower than that on a flat surface and is susceptible to cracking. This study aims to improve the crack resistance of the PAAO layer grown on a tubular aluminum substrate by adding ethylene glycol (EG). Each bath contained additive concentrations of 0, 5, 10, and 15 vol% EG. Anodization proceeded for 4 h at a temperature of 10 ℃ using the potentiostatic mode at 25 V in a sulfuric acid bath and …


Table Of Contents, The Editors Jun 2025

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.


Construction And Application Of A Tcn-Lstm-Svm-Based Time Series Prediction Model For Water Inflow In Coal Seam Roofs, Liu Xuan, Ji Yadong, Zhu Kaipeng, Zhao Chunhu, Li Kai, Li Chaofeng, Yuan Chenhan, Li Panpan, Yan Pengzhen Jun 2025

Construction And Application Of A Tcn-Lstm-Svm-Based Time Series Prediction Model For Water Inflow In Coal Seam Roofs, Liu Xuan, Ji Yadong, Zhu Kaipeng, Zhao Chunhu, Li Kai, Li Chaofeng, Yuan Chenhan, Li Panpan, Yan Pengzhen

Coal Geology & Exploration

Background The accurate prediction of mine water inflow plays a significant role in the prevention and control of water hazards and the safe and efficient production in coal mines. Methods To construct a prediction model of water inflow in mines under threat of water hazards from extremely thick sandstones aquifer in West China, this study investigated a typical mine (also referred to as the studied mine) severely affected by such water hazards in the Binchang mining area of Shaanxi Province. The correlation between the mining footage and water inflow of the mining face was selected as the characteristic variable for …


Influencing Patterns Of Low-Temperature Nitrogen On The Pore Structure And Oxidation Characteristics Of Lignite, Xie Shuliang, Wang Gang, Qu Qingdong, Liu Hao, Sun Lulu Jun 2025

Influencing Patterns Of Low-Temperature Nitrogen On The Pore Structure And Oxidation Characteristics Of Lignite, Xie Shuliang, Wang Gang, Qu Qingdong, Liu Hao, Sun Lulu

Coal Geology & Exploration

Objective During fire prevention and extinguishment for mines, injecting normal-temperature nitrogen into goaves can only play an inerting role. Meanwhile, the preparation of liquid nitrogen is complicated and costly. Therefore, in the Wudong Coal Mine in Xinjiang, low-temperature gaseous nitrogen of –40 ℃ was prepared using nitrogen cooling devices and then injected into goaves to prevent the spontaneous combustion of residual coals. However, the influencing patterns of low-temperature nitrogen on the pore structures and oxidation characteristics of residual coals in goaves remain poorly understood. This tends to affect the prediction and forecast of the secondary oxidation of residual coals in …


Mechanisms Underlying Differential Helium Enrichment In Shale Gas Of Varying Structural Styles In The Southeastern Sichuan Basin, Xin Zhiyuan, Chen Jianfa, Wang Jie, Ma Yong Jun 2025

Mechanisms Underlying Differential Helium Enrichment In Shale Gas Of Varying Structural Styles In The Southeastern Sichuan Basin, Xin Zhiyuan, Chen Jianfa, Wang Jie, Ma Yong

Coal Geology & Exploration

Objective Shale gas reservoirs hold considerable helium reserves despite relatively low helium abundance, establishing them as a critical replacement for helium production growth. The southeastern Sichuan Basin exhibits diverse structural styles with varying preservation conditions, leading to an unclear understanding of the distribution characteristics and enrichment patterns of helium in shale gas. Determining the mechanisms behind the differential helium enrichment in shale gas is significant for the effective utilization of helium in shale gas.Methods Focusing on the typical shale gas reservoirs of different structural styles in the southeastern Sichuan Basin, this study explored the mechanisms underlying differential helium accumulation …