Article
Mathematics
Dossan Baigereyev, Dinara Omariyeva, Nurlan Temirbekov, Yerlan Yergaliyev, Kulzhamila Boranbek
Summary: This paper proposes an efficient numerical method for solving a coupled system of equations consisting of a nonlinear parabolic partial integro-differential equation and an elliptic equation with a nonlinear term, which has important applied significance in petroleum engineering and modeling two-phase nonequilibrium fluid flows in a porous medium. The numerical method is constructed based on employing the finite element method in the spatial direction and the finite difference approximation to the time derivative, using Newton's method and second-order approximation formula for treating nonlinear terms.
Article
Automation & Control Systems
Zhaolin Yuan, Xiaorui Li, Di Wu, Xiaojuan Ban, Nai-Qi Wu, Hong-Ning Dai, Hao Wang
Summary: This study proposes an integrated deep-learning continuous-time network structure to predict outputs of thickening systems, addressing the challenges posed by their unique properties. Through a case study, the proposed model achieves better prediction performance compared to existing models and reduces negative effects from long time delays.
IEEE-CAA JOURNAL OF AUTOMATICA SINICA
(2022)
Article
Mathematics, Applied
Vijay Kumar Patel, Somveer Singh, Vineet Kumar Singh
Summary: This article discusses a new wavelets approximation scheme based on operational matrices for solving initial value complex partial differential equations arising from continuous wavelet transform. The algorithm developed converts CPDE into a system of PDEs, which is further converted into couple PDEs in terms of real and imaginary component. After implementation of wavelets scheme, the system of PIDEs is reduced into a system of algebraic equations.
NUMERICAL METHODS FOR PARTIAL DIFFERENTIAL EQUATIONS
(2021)
Article
Computer Science, Theory & Methods
Xiao-Ming Liu, Jun Jiang, Ling Hong
Summary: This article presents a numerical method for solving fuzzy differential equations using differential inclusions, with theoretically proven equivalence to the fuzzy master equation. The method is validated through comparison between numerical and analytical solutions in two examples, providing efficient and low-memory computational capabilities.
FUZZY SETS AND SYSTEMS
(2021)
Article
Engineering, Chemical
Raimund Burger, Julio Careaga, Stefan Diehl, Romel Pineda
Summary: A model of reactive settling is developed for the activated sludge process in wastewater treatment, which accounts for the spatial variability of reaction rates caused by biomass concentration variation. The model includes nonlinear partial differential equations and a numerical scheme for simulating hindered settling, compression, particle dispersion, and fluid dispersion. Experimental data from a pilot plant are used to fit the model, resulting in good predictability of the reactive sedimentation process.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Mathematics, Applied
Boonrod Yuttanan, Mohsen Razzaghi, Thieu N. Vo
Summary: This paper presents a numerical method for solving distributed-order fractional partial differential equations by introducing fractional-order generalized Taylor wavelets and studying the estimation of the approximation error. A formula for determining the Riemann-Liouville fractional integral operator for the wavelets is provided using the regularized beta function, and combined with Gauss-Legendre quadrature to obtain the numerical method. Several illustrative examples are given to demonstrate the applicability and accuracy of the proposed method.
APPLIED NUMERICAL MATHEMATICS
(2021)
Article
Mathematics, Applied
Nadiyah Hussain Alharthi, Abdon Atangana, Badr S. Alkahtani
Summary: In this study, a general partial differential equation with the fractal-fractional derivative, the power law kernel and the generalized Mittag-Leffler function was investigated. Due to limited research in this field, there is a lack of numerical schemes for solving partial differential equations with fractal-fractional derivatives. Therefore, this study attempts to provide a numerical method for solving these equations in various circumstances. The heat equation was used as an example to demonstrate the applicability of the proposed method.
Article
Mathematics, Interdisciplinary Applications
Adel Rashad Hadhoud, Faisal Ezz-Eldeen Abd Alaal, Taha Radwan
Summary: This paper presents an approach to approximate the solution of a nonlinear conformable space-time fractional partial differential equation using Cubic B-spline polynomials and the Galerkin method. Two test problems demonstrate the accuracy and efficiency of the proposed approach. The Von Neumann approach is applied to establish the stability conditions.
FRACTALS-COMPLEX GEOMETRY PATTERNS AND SCALING IN NATURE AND SOCIETY
(2022)
Article
Engineering, Electrical & Electronic
Sandeep Malik, Mir Sajjad Hashemi, Sachin Kumar, Hadi Rezazadeh, W. Mahmoud, M. S. Osman
Summary: The purpose of this work is to find innovative exact solutions for nonlinear partial differential equations using the new Kudryashov approach. The technique provides novel exact solutions of soliton types. 3D and 2D plots of higher dimensional Klein-Gordon, Kadomtsev-Petviashvili, and Boussinesq equations are shown to better understand the nonlinear wave structures. The new Kudryashov technique is effective and simple, providing new generalized solitonic wave profiles that enhance the understanding of the development and dynamic nature of such models.
OPTICAL AND QUANTUM ELECTRONICS
(2023)
Article
Mathematics, Applied
Ghaleb Gumah
Summary: In this paper, a numerical method based on a reproducing kernel theory is proposed to solve fuzzy heat and fuzzy wave equations in a reproducing kernel Hilbert space. Approximate solutions are derived for the aforementioned equations due to the complexity of establishing exact solutions. Additionally, the convergence of the reproducing kernel Hilbert space method is discussed using the concept of reproducing kernel function and related theorems and lemmas. Two numerical examples are presented to demonstrate the accuracy and computational efficiency of the proposed method.
COMPUTATIONAL & APPLIED MATHEMATICS
(2022)
Article
Mathematics, Applied
P. A. Zegeling, M. W. F. van Spengler
Summary: We introduce a class of Boundary Value Methods (BVMs) that can be applied to semi-stable and unstable Partial Differential Equation (PDE) models. These methods overcome the limitations of step-by-step methods by providing numerical stability regions that intersect with significant parts of the complex plane. We demonstrate the usefulness of BVMs through numerical experiments on various PDE models.
JOURNAL OF COMPUTATIONAL AND APPLIED MATHEMATICS
(2023)
Article
Physics, Multidisciplinary
Sanaullah Mastoi, Abdul Hamid Ganie, Abdulkafi Mohammed Saeed, Umair Ali, Umair Ahmed Rajput, Wan Ainun Mior Othman
Summary: This research aims to establish a novel algorithm in the finite difference method (FDM) by proposing a new idea in the mesh generation process. The newly proposed method, employing randomly generated grids, is compared with the uniform grid method to validate its effectiveness in reducing computational time and error. The study demonstrates the potential of the proposed method in improving the accuracy and efficiency of solving partial differential equations.
Article
Mathematics, Applied
Yongtang Chen, Qi Wang
Summary: This paper deals with the convergence and stability of the spectral collocation method for a hyperbolic partial differential equation with piecewise continuous arguments. The convergence of continuous-time and discrete-time collocation methods is analyzed using equivalent schemes and L-2 norm. The stability of the two numerical schemes is analyzed using Fourier analysis. Numerical experiments are conducted to demonstrate the theoretical results.
COMPUTATIONAL & APPLIED MATHEMATICS
(2022)
Article
Mathematics, Applied
Marc Jornet
Summary: In this paper, the uncertainty propagation of Burgers' equation with random initial condition and viscosity is quantified using the differential transform method. Convergence of the inverse differential transform is shown to only be expected in a small neighborhood in space-time when the input random parameters have small dispersion. Rapid approximations of main statistics and density function can be determined at virtually no computational cost in the region of convergence.
NONLINEAR ANALYSIS-THEORY METHODS & APPLICATIONS
(2021)
Article
Mathematics
Xiaobin Sun, Longjie Xie, Yingchao Xie
Summary: This study demonstrates the averaging principle for slow-fast stochastic partial differential equations with bounded and Holder continuous drift coefficients using Zvonkin's transformation technique and classical Khasminskii's time discretization method. An example is also provided to illustrate the result.
JOURNAL OF DIFFERENTIAL EQUATIONS
(2021)
Article
Chemistry, Physical
A. Y. Gebreyohannes, T. Geens, A. Kubarev, M. Roeffaers, W. Naessens, T. Swusten, T. Verbiest, I Nopens, Suzana P. Nunes, I. F. J. Vankelecom
Summary: The structures and distribution of enzymatically active magnetic-responsive dynamic layers in a crossflow superparamagnetic biocatalytic membrane reactor were investigated. The trade-off between mass transfer rate, fouling tendency, and dynamic layer stability depends on various forces acting on the Enz(SP). Real-time visual inspection of the biointerface was achieved through computational fluid dynamics-guided design of a crossflow system and fluorescence microscopy imaging.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2021)
Article
Pharmacology & Pharmacy
Ana Alejandra Barrera Jimenez, Daan Van Hauwermeiren, Michiel Peeters, Thomas De Beer, Ingmar Nopens
Summary: The pharmaceutical industry has shifted from traditional batch production to continuous manufacturing, utilizing continuous twin-screw wet granulation and advanced modeling tools. Improving understanding of the physical process within the granulator and enhancing current population balance models are essential for successful continuous production.
Article
Pharmacology & Pharmacy
Ashish Kumar, Stefan Radl, Krist Gernaey, Thomas De Beer, Ingmar Nopens
Summary: This study utilized discrete element method to experimentally characterize the solid-liquid mixing in a high shear wet granulation process in a twin-screw granulator, revealing the impact of particle flow and liquid distribution on the formation of agglomerates. The research demonstrated that agglomeration is a delayed process that occurs only when free liquid on particle surfaces is well distributed.
Article
Engineering, Multidisciplinary
Raimund Burger, Julio Careaga, Stefan Diehl, Romel Pineda
Summary: Reactive settling refers to the process of solid particles settling in a fluid while simultaneously undergoing reactions with the liquid phase. It plays a crucial role in sequencing batch reactors in wastewater treatment plants. A mathematical model is used to describe the operational cycles of the reactor and a finite difference scheme is employed to simulate the denitrification process.
APPLIED MATHEMATICAL MODELLING
(2022)
Article
Engineering, Chemical
Raimund Burger, Juan M. Menendez-Aguado, Marlon R. Fulla, Ismael E. Rivera
Summary: A population balance model is used to predict and analyze the wear and steel consumption of balls in a steel ball mill. The experimental data and theoretical predictions show excellent agreement, validating the accuracy of the model.
PARTICULATE SCIENCE AND TECHNOLOGY
(2022)
Article
Geochemistry & Geophysics
Zhuen Ruan, Aixiang Wu, Raimund Buerger, Fernando Betancourt, Rafael Ordonez, Jiandong Wang, Shaoyong Wang, Yong Wang
Summary: The shear-induced polymer-bridging flocculation is widely used in the solid-liquid separation process, and a flocculation kinetics model based on Population Balance Model (PBM) is proposed to model the process. The model includes an aggregation kernel and a breakage kernel, with six fitting parameters determined through global optimization. The proposed PBM effectively quantifies the dynamic evolution of floc size during flocculation.
Article
Infectious Diseases
Amna Tariq, Tsira Chakhaia, Sushma Dahal, Alexander Ewing, Xinyi Hua, Sylvia K. Ofori, Olaseni Prince, Argita D. Salindri, Ayotomiwa Ezekiel Adeniyi, Juan M. Banda, Pavel Skums, Ruiyan Luo, Leidy Y. Lara-Diaz, Raimund Burger, Isaac Chun-Hai Fung, Eunha Shim, Alexander Kirpich, Anuj Srivastava, Gerardo Chowell
Summary: This study utilizes mathematical models to investigate the transmission dynamics and short-term forecasting of the COVID-19 pandemic in Colombia. The findings show a decline in disease transmission at the national and regional level, but variations in incidence rate patterns across different departments. Additionally, the study examines the relationship between mobility and social media trends and the occurrence of case resurgences, along with the geographic heterogeneity of COVID-19 in Colombia.
PLOS NEGLECTED TROPICAL DISEASES
(2022)
Article
Geochemistry & Geophysics
Jiandong Wang, Aixiang Wu, Zhuen Ruan, Raimund Burger, Yiming Wang, Shaoyong Wang, Pingfa Zhang, Zhaoquan Gao
Summary: Cemented paste backfill (CPB) blended with coarse aggregates (CA-CPB) is a widely used technology for environmental protection and underground goaf treatment. This study investigates the influences of solid concentration, coarse aggregates dosage, and cement dosage on the rheological properties and compressive strength of CA-CPB through experimental methods. The results show that solid concentration and cement dosage have the most significant effects on the rheological properties and compressive strength, respectively. Multiple response optimization is performed using an overall desirability function approach to obtain the optimal parameters for high fluidity and strength, providing valuable information for the CA-CPB process in the Chifeng Baiyinnuoer Lead and Zinc Mine.
Article
Engineering, Multidisciplinary
Raimund Burger, Julio Careaga, Stefan Diehl, Romel Pineda
Summary: This article proposes a numerical scheme for simulating reactive settling in sequencing batch reactors (SBRs) in wastewater treatment plants. The scheme utilizes a complex mathematical model to accurately describe the reactive settling process and has been validated through simulations.
APPLIED MATHEMATICAL MODELLING
(2022)
Article
Engineering, Chemical
Raimund Burger, Julio Careaga, Stefan Diehl, Romel Pineda
Summary: A model of reactive settling is developed for the activated sludge process in wastewater treatment, which accounts for the spatial variability of reaction rates caused by biomass concentration variation. The model includes nonlinear partial differential equations and a numerical scheme for simulating hindered settling, compression, particle dispersion, and fluid dispersion. Experimental data from a pilot plant are used to fit the model, resulting in good predictability of the reactive sedimentation process.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Mathematics, Applied
Paulo Amorim, Raimund Burger, Rafael Ordonez, Luis Miguel Villada
Summary: This study investigates the spatio-temporal evolution of three biological species in a food chain model consisting of two competitive preys and one predator with intra-specific competition. The model considers the diffusion of the predator species towards higher concentrations of a chemical substance produced by the prey, as well as the movement of the prey away from high concentrations of a substance secreted by the predators. The study proves the local existence of nonnegative solutions and provides numerical simulations to discuss the system.
NONLINEAR ANALYSIS-REAL WORLD APPLICATIONS
(2023)
Article
Mathematics, Applied
Raimund Buerger, Sonia Valbuena, Carlos A. Vega
Summary: A reduced model of blood flow in arteries is proposed as a hyperbolic system of balance laws in one dimension with the unknowns as cross-sectional area and average flow velocity. An entropy stable finite difference scheme is constructed based on the entropy pair property, employing fourth-order entropy conservative flux and sign-preserving reconstruction, as well as a second-order strong stability preserving Runge-Kutta method. The scheme is computationally inexpensive, well-balanced, and numerically validated.
NUMERICAL METHODS FOR PARTIAL DIFFERENTIAL EQUATIONS
(2023)
Article
Geochemistry & Geophysics
Fernando Betancourt, Raimund Burger, Stefan Diehl, Leopoldo Gutierrez, M. Carmen Marti, Yolanda Vasquez
Summary: This article investigates the operation model of a froth flotation column. The model is described by a nonlinear convection-diffusion partial differential equation, incorporating solids-flux and drift-flux theories as well as a model of foam drainage. The model predicts the variations of bubble and (gangue) particle volume fractions with height and time. Through comparison with experimental results, operating charts for a modified version of the model are derived for steady-state operations with a stationary froth layer.
Article
Engineering, Chemical
Gezhong Chen, Cuiping Li, Zhuen Ruan, Raimund Burger, Yuan Gao, Hezi Hou
Summary: This study analyzed the bed drainage channel structure and the effect of coarse particles on the bed porosity and pore connectivity in cemented paste backfill technology. The results showed that the pressure and shear significantly influenced the spherical pore diameter, throat channel radius, and throat channel length. The volume and number of coarse particles had a negative impact on the bed porosity and pore connectivity. This research provides guidance for improving mining efficiency and reducing the number of tailings ponds.
MINERALS ENGINEERING
(2023)
Article
Mathematics, Interdisciplinary Applications
Raimund Burger, Stefan Diehl, M. Carmen Marti, Yolanda Vasquez
Summary: This article formulates a triangular system of conservation laws with discontinuous flux to model the one-dimensional flow of two disperse phases through a continuous one. The triangularity is due to the distinction between a primary and a secondary disperse phase, where the movement of the primary disperse phase is independent of the local volume fraction of the secondary phase. The article presents a monotone numerical scheme supported by theoretical arguments, and provides numerical examples and estimations of numerical error and convergence rates.
NETWORKS AND HETEROGENEOUS MEDIA
(2023)
Article
Engineering, Environmental
Rong-Gui Zhu, Chang-Gui Pan, Feng-Jiao Peng, Chao-Yang Zhou, Jun-Jie Hu, Kefu Yu
Summary: This comprehensive survey investigated the occurrence, bioaccumulation, and trophic magnification of parabens and their metabolite 4-HB in a marine food web. Results showed that parabens were the predominant pollutants in marine organisms, with significant bioaccumulation from sediments. The estimated trophic magnification factor indicated biomagnification for MeP and trophic dilution for 4-HB. Overall, the risks for humans consuming marine organisms were found to be low.
Article
Engineering, Environmental
Andres F. Torres-Franco, Deborah Leroy-Freitas, Cristina Martinez-Fraile, Elisa Rodriguez, Pedro A. Garcia-Encina, Raul Munoz
Summary: Anaerobic and microalgae-based technologies have emerged as sustainable alternatives for municipal wastewater treatment. However, the presence of viruses in the treated wastewater is a major concern for reuse applications. This study assessed the ability of these technologies to reduce viruses during secondary wastewater treatment. The results showed that all technologies were effective in reducing the concentration of viruses, with microalgae-based treatment exhibiting the highest potential for reducing the disinfection requirements of treated wastewater.
Article
Engineering, Environmental
Young Gwang Kim, Sae Yun Kwon, Spencer J. Washburn, Scott C. Brooks, Ji Won Yoon, Lucien Besnard
Summary: The study uses Hg isotope ratios to identify the sources and exposure pathways of mercury in bivalves, finding that dissolved Hg phases in the water column are the primary source and exposure pathway to bivalves. This provides new insights into using bivalves as bioindicators for sediment quality monitoring.
Article
Engineering, Environmental
Hui Geng, Ying Xu, Rui Liu, Dianhai Yang, Xiaohu Dai
Summary: This study investigates the effect of cation exchange resin (CER) on the sequential recovery of hydrogen and methane from anaerobic digestion (AD) and the corresponding mechanisms. The results show that CER can simultaneously enhance the production of hydrogen and methane by promoting the solubilisation, hydrolysis, and acidification of organic matter. Additionally, CER facilitates effective contact between bacteria and organic particulates and reduces the energy barrier for mass transfer during methane production. The study also reveals changes in the microbial community structure and metagenomics during the AD process.
Article
Engineering, Environmental
Xiaojing Lin, Zhan Jin, Shunfeng Jiang, Zhiquan Wang, Suqing Wu, Ke Bei, Min Zhao, Xiangyong Zheng
Summary: Dehumidification combined with addition of absorbent resin supplement (ARS) was used to achieve rapid evaporation of non-pretreated urine, resulting in high water evaporation efficiency and nutrient recovery.
Article
Engineering, Environmental
Yangli Che, Chaoran Lin, Shen Li, Jiao Liu, Longhai Zhu, Shilei Yu, Nan Wang, Haoshuai Li, Mutai Bao, Yang Zhou, Tonghao Si, Rui Bao
Summary: Hydrodynamic processes play a crucial role in the transmission of sediments, microbial assembly, and organic carbon redistribution in the ocean. Through experiments and analysis, we found that hydrodynamics shape the assembly of microbial communities and control the redistribution of different sourced organic carbon, thereby influencing microbial-mediated biogeochemical transformation.
Article
Engineering, Environmental
Chao Chen, Yu Yang, Nigel J. D. Graham, Zhenyu Li, Xingtao Yang, Zhining Wang, Nadia Farhat, Johannes S. Vrouwenvelder, Li -an Hou
Summary: The fouling of seawater reverse osmosis membranes is a persistent challenge in desalination. This study monitored the operational performance of a desalination plant for 7 years and the fouling development in different areas of membrane modules. The findings showed that operational performance declined over time and fouling mainly occurred at the feed side of the modules, with the highest microbial diversity. Keystone species like Chloroflexi and Planctomycetes played an important role in maintaining community structure and biofilm maturation. Polysaccharides, soluble microbial products, marine humic acid-like substances, and inorganic substances contributed to fouling. Overall, biofouling had a significant impact on membrane fouling after 7 years of operation.
Article
Engineering, Environmental
Dan Li, Jieyi Sun, Yibo Fu, Wentao Hong, Heli Wang, Qian Yang, Junhong Wu, Sen Yang, Jianhui Xu, Yunfei Zhang, Yirong Deng, Yin Zhong, Ping'an Peng
Summary: Sulfidation-oxidation treatment of magnetite (Fe3O4) enhances the production of dark center dot OH, which can efficiently degrade dissolved organic matter (DOM) and accelerate carbon cycling.
Article
Engineering, Environmental
Cheng Yu, Kaijun Wang, Kaiyuan Zhang, Ruiyang Liu, Pingping Zheng
Summary: This study implemented a microaerobic-aerobic configuration in a full-scale municipal wastewater treatment facility and investigated the effects on sludge characteristics, pollutant removal, microbial community, and granulation mechanisms. The results showed successful transition from flocculent-activated sludge to well-defined AGS after two months of operation. The primary pathways for pollutant removal were simultaneous nitrification, denitrification, and phosphorus removal. Moreover, the incorporation of internal separators induced shifts in the flow pattern, which promoted granulation.
Article
Engineering, Environmental
Zhe Zhang, Shaoyang Hu, Guangrong Sun, Wei Wang
Summary: Halogenated aromatic disinfection byproducts (DBPs), such as halogenated phenols, have garnered widespread attention due to their high toxicity and prevalence. This study reports on the analysis, occurrence, and cytotoxicity of a group of emerging halogenated aromatic DBPs, known as halogenated polyhydroxyphenols (HPPs), in drinking water.
Article
Engineering, Environmental
Shengyue Chen, Jinliang Huang, Peng Wang, Xi Tang, Zhenyu Zhang
Summary: Accurate prediction of river water quality is crucial for sustainable water management. This study introduces wavelet analysis and transfer learning techniques to assist LSTM modeling, proposing a newly coupled modeling approach that improves short-term prediction of river water quality.
Article
Engineering, Environmental
Bang Du, Xinmin Zhan, Piet N. L. Lens, Yifeng Zhang, Guangxue Wu
Summary: Efficient anaerobic digestion relies on the cooperation of different microorganisms with different metabolic pathways. This study investigated the effects of different operational modes and the addition of powdered activated carbon (PAC) on ethanol metabolic pathways. The results showed that the SBR mode and the presence of CO2 facilitated ethanol metabolism towards propionate production, while the CFR mode with extended solids retention time enriched Geobacter. Adjusting operational modes and PAC addition can modulate anaerobic ethanol metabolism and enrich Geobacter.
Article
Engineering, Environmental
Wanfa Wang, Si-Liang Li, Jun Zhong, Yuanbi Yi, Fujun Yue, Zenglei Han, Qixin Wu, Ding He, Cong-Qiang Liu
Summary: This study compares the carbon biogeochemical processes in karst and non-karst regions within large thermal stratified river-reservoir systems. The results demonstrate that karst reservoirs have a reduced potential for carbon emissions and highlight the importance of considering geologic settings to improve accuracy in regional and global CO2 emission estimates.
Article
Engineering, Environmental
Chunxia Jiang, Zelong Zhao, Dong Zhu, Xiong Pan, Yuyi Yang
Summary: This study analyzed the occurrence and distribution of antibiotic resistance genes (ARGs) in different environmental media of the Yangtze River using metagenomics. Core resistome dominated by multidrug resistance genes was found in all samples, while rare resistome dominated by various resistance genes was more prevalent in plasmids. Specific bacteria were identified as hosts for both core and rare resistomes, with high clinical concern ARGs found in the rare resistome. Particle-associated environment provided the most ideal conditions for resistome hosts. This study provided insights into the genetic locations of ARGs and the community assembly mechanisms of ARG hosts in freshwater environments.
Article
Engineering, Environmental
Yu Zhang, Yongtao He, Linchun Jia, Lei Xu, Zheng Wang, Yueling He, Ling Xiong, Xumeng Lin, Hong Chen, Gang Xue
Summary: By synergizing organic carbon source, thiosulfate, and zero-valent iron, efficient mixotrophic denitrification of oligotrophic secondary effluent can be achieved. Thiosulfate plays a vital role in promoting TN removal efficiency, while corrosion of Fe0 releases OH- to neutralize H+ from thiosulfate-driven denitrification, creating a suitable environment for denitrification. The coordination of thiosulfate and Fe0 maintains the dominance of Thiobacillus for denitrification.