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Analysis of CH_(4) and H_(2) Adsorption on Heterogeneous Shale Surfaces Using aMolecular Dynamics Approach

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Fluid Dynamics & Materials Processing 2024年第1期20卷 31-44页

作者： Surajudeen Sikiru Hassan Soleimani Amir Rostami Mohammed Falalu Hamza Lukmon owolabi Afolabi Centre of Subsurface Imaging(CSI) Universiti Teknologi PETRONASTronohPerakMalaysia Department of Geosciences Universiti Teknologi PETRONASBandar Seri IskandarTronohPerakMalaysia Department of Pure&Industrial Chemistry Faculty of Physical SciencesBayero University KanoKanoNigeria Department of Mechanical Engineering Engineering Institute of TechnologyMelbourne Campus VictoriaMelbourneAustralia

Determining the adsorption of shale gas on complex surfaces remains a challenge in molecular simulation *** essentially stem from the need to create a realistic shale structure model in terms of mineral heterogeneityand ***,precise characterization of the competitive adsorption of hydrogen andmethane in shale generally requires the experimental determination of the related adsorptive *** thisstudy,the adsorption of adsorbates,methane(CH_(4)),and hydrogen(H_(2))on heterogeneous shale surface modelsof Kaolinite,Orthoclase,Muscovite,Mica,C_(60),and Butane has been simulated in the frame of a moleculardynamic’s numerical *** results show that these behaviors are influenced by pressure and *** increasing the pressure from 500 to 2000 psi,the sorption effect for CH_(4)significantly increasesbut shows a decline at a certain stage(if compared to H_(2)).The research findings also indicate that raw shalehas a higher capacity to adsorb CH_(4)compared to ***,in shale,this difference is negligible.

关键词： Shale gas adsorption methane hydrogen molecular dynamic sorption

Unveiling Global Human Trafficking Trends: A Comprehensive Analysis

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Journal of Data Analysis and Information Processing 2024年第1期12卷 49-75页

作者： Somtobe Olisah Clement Odooh Oghenekome Efijemue Echezona Obunadike Jane Onwuchekwa Omoshola owolabi Saheed Akintayo Callistus Obunadike Department of Computer Science Austin Peay State University Clarkesville TN USA Department of Data Science Carolina University Winston-Salem NC USA

This paper presents a comprehensive analysis of global human trafficking trends over a twenty-year period, leveraging a robust dataset from the Counter Trafficking Data Collaborative (CTDC). The study unfolds in a systematic manner, beginning with a detailed data collection phase, where ethical and legal standards for data usage and privacy are strictly observed. Following collection, the data undergoes a rigorous preprocessing stage, involving cleaning, integration, transformation, and normalization to ensure accuracy and consistency for analysis. The analytical phase employs time-series analysis to delineate historical trends and utilizes predictive modeling to forecast future trajectories of human trafficking using the advanced analytical capabilities of Power BI. A comparative analysis across regions—Africa, the Americas, Asia, and Europe—is conducted to identify and visualize the distribution of human trafficking, dissecting the data by victim demographics, types of exploitation, and duration of victimization. The findings of this study not only offer a descriptive and predictive outlook on trafficking patterns but also provide insights into the regional nuances that influence these trends. The article underscores the prevalence and persistence of human trafficking, identifies factors contributing to its evolution, and discusses the implications for policy and law enforcement. By integrating a methodological approach with quantitative analysis, this research contributes to the strategic planning and resource allocation for combating human trafficking. It highlights the necessity for continued research and international cooperation to effectively address and mitigate this global issue. The implications of this research are significant, offering actionable insights for policymakers, law enforcement, and advocates in the ongoing battle against human trafficking.

关键词： Human Trafficking Global Trends Data Analysis Victim Demographics Policy Implications Technological Advancements Socioeconomic Factors Forecasting Regional Disparities Transnational Crime

A Cross-Sectional Study on the Impact of Operation Triple Zero (OTZ) Program on Viral Load Suppression amongst Members of the Adolescent Club in 68 Nigerian Army Reference Hospital Yaba Lagos, Nigeria

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World Journal of AIDS 2024年第2期14卷 35-44页

作者： Nkechinyere Harrison Ismail Lawal Yakubu Adamu Kehinde Aribisala Adegbenga Olarinoye Uzoamaka Agbaim Funmilayo owolabi Dooshima Okonkwo Laura Chittenden Nathan Okeji Centre for Infectious Disease Clinic 68 Nigerian Army Reference Hospital Lagos Nigeria United States Army Medical Research Directorate-Africa Abuja Nigeria Henry Jackson Foundation Medical Research International LTD/GTE Abuja Nigeria Nigerian Ministry of Defence Health Implementation Program Abuja Nigeria

Background: In Nigeria, adolescents and young people (AYP) aged 10 - 24, comprise 22.3% of the population and with HIV prevalence of 3.5%. The AYP living with HIV enrolled at the 68 NARHY, Lagos reflects the national challenges with poor viral suppression. The OTZ program aligns with the UNAIDS 95-95-95 goals. It seeks to empower AYPLHIV to be in charge of their treatment and commit to triple zero outcomeszero missed appointments, zero missed drugs, and zero viral loads. The purpose of the study was to assess the impact of the OTZ program on viral load suppression among members of the adolescent club in 68 NARHY, Lagos. Method: A cross-sectional retrospective study to evaluate the impact of the OTZ program on the viral load of 53 AYP enrolled in the OTZ program between March 2019 to December 2019 was analyzed. The Percentage of viral load suppression before enrollment compared with 6 and 12 months after enrollment into the OTZ program. The AYP is grouped into 10 - 14, 15 - 19, and 20 - 24 years. Activities conducted were peer driven monthly meetings with the AYP during which the adolescents interacted on issues relating to improving their treatment outcomes, healthcare workers reviewed their clinical status, viral load result, provider peer counseling, and caregivers engagement to support adherence to medication and ARV refills. Results: Before OTZ, 81% aged 10 - 14 years, 75% aged 15 - 19 years, and 25% aged 20 - 24 years were virally suppressed (VL less than 1000 copies/ml). Six months after enrollment, 94% were virally suppressed95% aged 10 - 14 years, 96% aged 15 - 19 years, and 66% aged 20-24 years. Twelve months after enrollment, 96% of AYP were virally suppressed100% aged 10-14 years, 93% aged 15 - 19 years, and 100% aged 20 - 24 years. Males viral load (VL) suppression improved from 79% to 96% and 92%, while females VL suppression improved from 69% to 93% and 100% at 6 and 12 months respectively. Conclusion: The OTZ activities contributed to improved viral l

关键词： Impact Operation Triple Zero Adolescent Viral Load Nigeria

First-Principles Investigation of Charge Transfer Mechanism of B-Doped 3C-SiC Semiconductor Material

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World Journal of Condensed Matter Physics 2024年第2期14卷 35-44页

作者： Abdullahi Alkali Dauda Muhammad Yusuf Onimisi Adeyemi Joshua owolabi Hameed Adeneyi Lawal Hassan Muhammad Gambo Bashir Mohammed Aliyu Surajo Bala Muhammad Lamido Madugu Muhammad Abdurrahman Nainna Johnson Akinade Bamikole Physics Department Faculty of Science Air Force Institute of Technology Kaduna Nigeria Physics Department Faculty of Science Nigeria Defence Academy Kaduna Nigeria Physics Department Umaru Musa Yar&#8217adua University Batagarawa Nigeria Physics Department Faculty of Science Gombe State University Gombe Nigeria Physics Department Federal University of Lafia Lafia Nigeria

This study delves into the charge transfer mechanism of boron (B)-doped 3C-SiC through first-principles investigations. We explore the effects of B doping on the electronic properties of 3C-SiC, focusing on a 12.5% impurity concentration. Our comprehensive analysis encompasses structural properties, electronic band structures, and charge density distributions. The optimized lattice constant and band gap energy of 3C-SiC were found to be 4.373 Å and 1.36 eV respectively, which is in agreement with previous research (Bui, 2012;Muchiri et al., 2018). Our results show that B doping narrows the band gap, enhances electrical conductivity, and influences charge transfer interactions. The charge density analysis reveals substantial interactions between B dopants and surrounding carbon atoms. This work not only enhances our understanding of the material’s electronic properties, but also highlights the importance of charge density analysis for characterizing charge transfer mechanisms and their implications in the 3C-SiC semiconductors.

关键词： First-Principles Calculations DFT Boron (B)-Doped 3C-SiC Charge Transfer

Analysis of Mathematics and Numerical Pattern Formation in Superdiffusive Fractional Multicomponent System

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Advances in Applied Mathematics and Mechanics 2017年第6期9卷 1438-1460页

作者： kolade M.owolabi Abdon Atangana Institute for Groundwater Studies Faculty of Natural and Agricultural SciencesUniversity of the Free StateBloemfontein 9300South Africa

In this work,we examine the mathematical analysis and numerical simulation of pattern formation in a subdiffusive multicomponents fractional-reactiondiffusion system that models the spatial interrelationship between two preys and predator *** major result is centered on the analysis of the system for linear *** of the main model reflects that the dynamical system is locally and globally asymptotically *** propose some useful theorems based on the existence and permanence of the species to validate our theoretical *** and efficient methods in space and time are formulated to handle any space fractional reaction-diffusion *** numerically present the complexity of the dynamics that are theoretically *** simulation results in one,two and three dimensions show some amazing scenarios.

关键词： Asymptotically stable coexistence Fourier spectral method numerical simulations predator-prey fractional multi-species system

Modeling and Simulation of Microstructurally Small Crack Formation and Growth in Notched Nickel-base Superalloy Component

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Journal of Materials Science & Technology 2014年第3期30卷 203-212页

作者： G.M.owolabi H.A.Whitworth Department of Mechanical Engineering Howard University

Studies on microstructurally small fatigue cracks have illustrated that heterogeneous microstructural features such as inclusions, pores, grain size distribution as well as precipitate size distribution and volume fraction create stochasticity in their behavior under cyclic loads. Therefore, to enhance safe-life and damage-tolerance approaches, accurate modeling of the influence of these heterogeneous microstructural features on microstructurally small crack formation and growth from stress raisers is necessary. In this work, computational micromechanics was used to predict the high cycle fatigue of microstructurally small crack formation and growth in notched polycrystalline nickel-base superalloys and to quantify the variability in the driving force for formation and growth of microstructurally small crack from notch root in the matrix with non-metallic inclusions. The framework involves computational modeling to obtain three-dimensional perspectives of microstructural features influencing fatigue crack growth in notched nickel-base superalloys, which accounts for the effects of nonlocal notch root plasticity, loading, microstructural variability, and extrinsic defects on local cyclic plasticity at the microstructure-scale level. This approach can be used to explore sensitivity of minimum fatigue lifetime to microstructures. The simulation results obtained from this framework were calibrated to existing experimental results for polycrystalline nickel-base superalloys.

关键词： Microstructuraliy small crack Crystal plasticity Nickel-base superalloy Fatigue life

Pavement sustainability index for highway infrastructures： A case study of Maryland

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Frontiers of Structural and Civil Engineering 2018年第2期12卷 192-200页

作者： Stella O. OBAZEE-IGBINEDION Oludare owolabi Montgomery County Department of Transportation 100 Edison Park Drive Gaithersburg MD 20878 USA Department of Civil Engineering Morgan State University 1700 East Cold Spring Lane Baltimore MD 21251 USA

Pavement deterioration creates conditions that undermine their performances, which gives rise to the need for maintenance and rehabilitation. This paper develops a mathematical multi-linear regression analysis （MLRA） model to determine a pavement sustainability index （PSTI） as dependent variable for flexible pavements in Maryland. Four categories of pavement performance evaluation indicators are subdivided into seven pavement condition indices and analyzed as independent variables for each section of pavement. Data are collected from five different roadways using field evaluations and existing database. Results indicate that coefficient of determination （R^2） is correlated and significant, R^2 = 0.959. Of the seven independent variables, present serviceability index （PSI） is the most significant with a coefficient value of 0.032, present serviceability rating （PSR） coefficient value=0.028, and international roughness index （IRI） coefficient value = -0.001. Increasing each unit value of coefficients for PSI and PSR would increase the value of PSTI; thereby providing a more sustainable pavement infrastructure; which explains the significance of the model and why IR/ will most likely impact environmental, economic and social values.

关键词： pavement indices sustainability pavement performance flexible pavements

Shear Band Formation in AISI 4340 Steel Under Dynamic Impact Loads:Modeling and Experiment

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Acta Metallurgica Sinica(English Letters) 2013年第4期26卷 378-384页

作者： Daniel Odoh Gbadebo owolabi Akindele Odeshi Horace Whitworth Department of Mechanical Engineering Howard University Department of Mechanical Engineering University of Saskatchewan57 Campus DriveSaskatoonSKS7N 5A9Canada

In this study, the occurrence of the adiabatic shear bands in AISI 4340 steel under high velocity impact loading was investigated using finite element analysis and experimental tests. The cylindrical specimen subjected to the impact load was divided into different regions separated by nodes using finite element method in ABAQUS environment with boundary conditions specified. The material properties were assumed to be lower in the region where the probability of strain localization is high based on prior experimental results in order to initialize the formation of the adiabatic shear bands. The finite element model was used to determine the maximum flow stress, the strain hardening, the thermal softening, and the time to reach the critical strain for the formation of adiabatic shear bands. Experimental results show that deformed bands were formed at low strain rates and there was a minimum strain rate required for the formation of the transformed band in the alloy and the cracks were initiated and propagated along the transformed bands leading to fragmentation under the impact loading. The susceptibility of the adiabatic shear bands to cracking was markedly influenced by the strain-rates and the initial material microstructure. The simulation results obtained were compared with the experimental results obtained from the AISI 4340 steel under high strain-rate loading in compression using split impact Hopkinson bars. A good agreement between the experimental and simulation results was obtained.

关键词： Adiabatic shear bands Finite element model Strain hardening Thermal softening Johnson-Cook model AISI 4340 steel

Knowledge, Attitudes and Practices of Antibiotic Use and Antimicrobial Resistance among Medical Students in a Private University in Dominica, West Indies

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Advances in Microbiology 2022年第9期12卷 511-524页

作者： Simeon K. Olatunde Joshua B. owolabi Department of Molecular and Cellular Sciences All Saints University School of Medicine Roseau Dominica

Antibiotics are indispensable to maintaining human health, however, their overuse has resulted in resistant organisms which present a significantly higher burden to the low to middle income countries, due to the high incidence of communicable diseases. Insufficient antimicrobial-related training for physicians during their undergraduate education could have a negative impact on their prescribing. This study assessed the knowledge, attitudes and practices of antibiotic use and antimicrobial resistance among medical students in a private university in Dominica, a resource-limited country, in order to facilitate more effective education of these future prescribers. A cross-sectional study was undertaken with the medical students from February 2021 to April 2021 using a 36-item questionnaire. Data analysis was achieved using descriptive statistics. A total of 85 students participated in the study, majority (70%) were female, African, aged 23.8 ± 4.6 years and single. Between 64 and 99% of the respondents reported no risk factors for communicable diseases and demonstrated a low to moderate (10% - 40%) negative response to knowledge-related questions. The majority (70%) of the respondents who had used antibiotics in the past 12 months reported efficacy and limited side-effects, but confirmed lack of knowledge about the classes of antibiotics prescribed to them. Almost half of the medical students (48%) reported having abused antibiotics, while about a third (35%) of the respondents reported sharing antibiotics with friends or loved ones in the past. There was no significant association between age, gender, and the medical students’ knowledge of antibiotic resistance (p > 0.05). However, they reported that they would like more education on antimicrobial use and resistance. The medical students in this study showed knowledge of antimicrobial resistance, but lacked comprehension of components of antimicrobial stewardship, including prevention of inappropriate use and classes

关键词： Dominica African Medical Students Antibiotics Use Antimicrobial Resistance