Review
Construction & Building Technology
Katerina Ioannidou, Christophe Labbez, Enrico Masoero
Summary: This manuscript reviews the current state of the art in coarse-grained and mesoscale simulations of C-S-H, and highlights opportunities for future research.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Emma. H. H. Wolpert, Kim. E. E. Jelfs
Summary: The packing behavior of molecules has significant implications for their applications as functional molecular materials. However, predicting the crystal structure of organic molecules is a challenging problem in crystal engineering. This study focuses on the packing behavior of porous organic cages (POCs) and proposes a novel method to predict their solid-state phase behavior using a simplified model. The results demonstrate the influence of chemical functionality on the solid-state phase formation of POCs and pave the way for the development of design rules.
Article
Quantum Science & Technology
Karen Hovhannisyan, Mathias R. Jorgensen, Gabriel T. Landi, Alvaro M. Alhambra, Jonatan B. Brask, Marti Perarnau-Llobet
Summary: Accurate thermometry for quantum systems is crucial for technological advancement, but practical implementations often involve coarse-grained measurements. By utilizing tools from signal processing, we can achieve good temperature estimates even with a small number of outcomes. Our findings have implications for many-body systems and nonequilibrium thermometry, providing insights into optimal coarse-grained measurements and strategies for probe-based thermometry.
Article
Polymer Science
Max Meirow, Erik Luijten
Summary: The control of product distribution in the catalytic cleavage of plastic waste through tuning the pore diameter has been demonstrated. This knowledge is crucial for future synthetic improvements.
Article
Engineering, Environmental
Chengxiang Li, Ji Xu, Tianhao Qiu, Zikang Sun, Haolei Zhang, Wei Ge
Summary: Multi-scale porous structures in catalyst pellets or particles have a significant influence on the performance of chemical processes, but traditional continuum-based models do not accurately describe these structures. A trans-level multi-scale discrete computational framework is proposed to address this complexity and is demonstrated to be necessary and effective for bridging the intrinsic reaction kinetics with the performance of porous catalytic reactors. The method combines hard-sphere pseudo-particle modeling at the representative elementary volume (REV) scale with computational fluid dynamics/discrete element method (CFD-DEM) for reactor-level hydrodynamics. Experimental results show good agreement with the method's predictions, while a continuum approach may give significantly different and unreasonable results.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Polymer Science
Dirk Grommes, Martin R. Schenk, Olaf Bruch, Dirk Reith
Summary: In this study, the thermo-mechanical relaxation and crystallization behavior of polyethylene were investigated using mesoscale molecular dynamics simulations. The results show how chain length, temperature, local entanglements, and orientation of chain segments influence crystallization and relaxation behavior. The temperature dependent crystallization rate of polyethylene, including crystallization onset temperature, was determined from the models.
Article
Physics, Multidisciplinary
Irenee Frerot, Antonio Acin
Summary: This work demonstrates the application of self-testing in many-body systems and proves that membership in a set of (entangled) quantum states can be determined based on self-testing in the Bell scenario.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Physical
Xinqiang Ding, Bin Zhang
Summary: Coarse-grained models are useful for simulating complex systems and providing molecular insights. This study introduces a new method, potential contrasting, for efficiently learning force fields that accurately reproduce the conformational distribution produced by all-atom simulations. The technique has been applied to the Trp-cage protein and shows promise in capturing the thermodynamics of the folding process and improving force field transferability.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Chemistry, Multidisciplinary
Gustavo Giordani, Domenico Scaramozzino, Ignacio Iturrioz, Giuseppe Lacidogna, Alberto Carpinteri
Summary: Proteins play a crucial role in biological functions, with low-frequency modes and modal analysis being key in understanding their structural processes. Biochemical researchers use dynamic simulation techniques, while new proposals of simplified elastic models offer alternative approaches. Comparing experimental data with numerical solutions allows for the assessment of protein flexibility.
APPLIED SCIENCES-BASEL
(2021)
Article
Chemistry, Physical
Yangyang Zhang, Donghui Liu, Yiyang Zhang, Yachong Guo, Wenfei Li, Fabrice Thalmann
Summary: This article describes a coarse-grained model of POPC and DOPC lipid peroxides and discusses their predicted structure and the influence of hydration. In addition, electron and neutron scattering length density profiles of the simulated bilayers are provided.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Engineering, Chemical
Yong Zhang, Ji Xu, Qi Chang, Wei Ge
Summary: In this study, an improved coarse-grained discrete particle model was proposed to accurately simulate the hydrodynamics of gas-solid systems. By coupling coarse-grained particles with fine-scale gas flow through weight function, the model successfully captured the mesoscale heterogeneity in fluid velocity, solid concentration and interphase forces. A faster bi-layer model was also introduced to reduce computational cost while maintaining comparable accuracy.
CHEMICAL ENGINEERING SCIENCE
(2022)
Article
Polymer Science
Dirk Grommes, Martin R. Schenk, Olaf Bruch, Dirk Reith
Summary: This study investigates the initial stage of thermo-mechanical crystallization behavior for uni- and biaxially stretched polyethylene using a mesoscale molecular dynamics approach. The effects of stretching procedures on the micro-mechanical state of the systems are discussed, with a focus on entanglement behavior and nematic ordering of chain segments. The study reveals that the main stretching direction dominates the microscopic states of the different systems and that crystallization mainly depends on the (dis-)entanglement behavior, with nematic ordering playing a secondary role.
Article
Chemistry, Physical
Fabian Grunewald, Mats H. Punt, Elizabeth E. Jefferys, Petteri A. Vainikka, Melanie Koenig, Valtteri Virtanen, Travis A. Meyer, Weria Pezeshkian, Adam J. Gormley, Maarit Karonen, Mark S. P. Sansom, Paulo C. T. Souza, Siewert J. Marrink
Summary: The study develops a consistent strategy to accurately parametrize carbohydrate molecules within the framework of Martini 3 model and demonstrates the validity and transferability of this approach through various test cases.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Polymer Science
Manuel Quesada-Perez, Jose-Alberto Maroto-Centeno, Maria del Mar Ramos-Tejada, Alberto Martin-Molina
Summary: This work computes the longtime diffusion of a solute in a chemically crosslinked and flexible hydrogel using a coarse-grained model of a polymeric network. The relevance of chain flexibility becomes important when the polymer volume fraction and the solute size increase. The results show that solute particles can moderately diffuse in flexible hydrogels even when their diameter is comparable to the mesh size. The diffusion coefficients obtained here are in good agreement with previously reported experimental data, without the need for any adjustable parameter.
Article
Materials Science, Multidisciplinary
Shan-Zhen Li, Liang Tang, Shuang Tian, Xian-Zhang Ling, Yang-Sheng Ye, De-Gou Cai
Summary: This study investigated the effects of confining pressure and frozen temperature on coarse-grained materials using triaxial compression tests. A modified model considering microstructures of the material was proposed and validated through experimental results. The findings provide a useful reference for the analysis of frozen coarse-grained materials in geotechnical engineering.
ADVANCES IN MATERIALS SCIENCE AND ENGINEERING
(2021)
Article
Engineering, Environmental
Bhaskar Sarkar, Ram R. Ratnakar, Vemuri Balakotaiah
Summary: The study develops reduced order models for monolith reactors with catalytic reactions and homogeneous reactions using the Lyapunov-Schmidt (L-S) reduction technique, converting detailed models into multi-mode models. Various transfer coefficients and local transfer coefficient matrices are explored, highlighting the application of the reduced order models in different scenarios.
CHEMICAL ENGINEERING JOURNAL
(2021)
Review
Engineering, Chemical
Vemuri Balakotaiah, Zhe Sun, Ram Ratnakar
Summary: The article provides a detailed analysis of the ignition-extinction and hysteresis behavior in two widely used catalytic reactor models for a single exothermic reaction. Various practical estimation methods and scaling relations are provided to predict ignition/extinction loci.
REVIEWS IN CHEMICAL ENGINEERING
(2022)
Review
Chemistry, Physical
Ram R. Ratnakar, Nikunj Gupta, Kun Zhang, Casimir van Doorne, James Fesmire, Birol Dindoruk, Vemuri Balakotaiah
Summary: Hydrogen is considered a future fuel with LH2 technology having great potential. Development of cost-effective and safe technologies for storage and transportation is crucial for commercial widespread use. Storage and delivery are key enablers for global hydrogen technology but face challenges due to extremely low temperature constraints.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Energy & Fuels
Ram R. Ratnakar, Birol Dindoruk
Summary: Viscosity is a crucial parameter in oil reservoir conditions, particularly in thermal EOR techniques, but measuring viscosity at high temperatures poses challenges. A new technique using a capillary device has been proposed to perform high-temperature viscosity measurements without the need for additional oil samples, saving time and costs.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2021)
Article
Engineering, Chemical
Vemuri Balakotaiah, Ram R. Ratnakar
Summary: This study introduces novel modular reactor configurations with electrical resistance heating for endothermic reactions such as cracking and steam reforming of hydrocarbons, demonstrating their feasibility through calculations. The basic unit of each module consists of wires, tubes, plates, monolith, or gauze/wire meshes arranged in parallel or series to satisfy current-voltage constraints, with smaller dimensions selected for nearly uniform heating temperature within the reaction zone.
Article
Engineering, Environmental
Bhaskar Sarkara, Ram R. Ratnakar, Vemuri Balakotaiah
Summary: The study used a phase-averaged multi-mode multi-scale model to examine the ignition and extinction behavior of catalytically assisted lean combustion of hydrogen in a monolith reactor. Bifurcation theory was employed to classify the different ignition and extinction behaviors occurring, along with investigating the impact of various design and operating variables on the ignition-extinction behavior.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Engineering, Environmental
Mingjie Tu, Ram Ratnakar, Vemuri Balakotaiah
Summary: The novel procedure addresses the diffusional effects in monolith reactors with detailed micro-kinetic models by increasing mesh points and utilizing a multi-mode reduced order model. The reduced order model accurately calculates solutions and speeds up computations significantly by eliminating degrees of freedom associated with species diffusion.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Energy & Fuels
Ram R. Ratnakar, Santhosh Shankar, Ravi Agrawal, Birol Dindoruk
Summary: This study presents the modeling and experimental research on carbon dioxide adsorption, where a reduced-order model is developed to describe the transport and adsorption characteristics in a reactor. By analyzing experimental data and solving inverse problems, the model accuracy is improved and can be utilized for real-time optimization and reactor design.
JOURNAL OF NATURAL GAS SCIENCE AND ENGINEERING
(2021)
Article
Thermodynamics
Ram Ratnakar, Somil S. Gupta, Georg Stockinger, Wouter Hamer, Birol Dindoruk
Summary: Thermodynamic models for ammonia-MEA-water mixtures are presented in this study, and the pH of aqueous streams for corrosion control in water-utility applications is evaluated. An equation of state (EOS) model using Peng-Robinson EOS with the asymmetric Huron-Vidal (HV) mixing rule is developed and calibrated against experimental data. A modeling workflow is developed to estimate the pH of aqueous streams based on temperature and composition. These studies are crucial for chemical and manufacturing industries, and the methodologies can be applied to a wider range of pressures and temperatures in water utilities, reactor plants, and refineries.
FLUID PHASE EQUILIBRIA
(2022)
Review
Engineering, Chemical
Ram R. Ratnakar, Birol Dindoruk
Summary: This article discusses the mixing processes in multiphase fluid systems. In such systems, fluid/component mixing is complex and influenced by factors such as pressure, temperature, and time. Understanding these processes is crucial for the development of technologies that utilize these concepts, such as enhanced oil recovery and gas injection.
Review
Chemistry, Physical
Ram R. Ratnakar, Zhe Sun, Vemuri Balakotaiah
Summary: This work provides an accurate estimation of the effective thermal conductivity of insulation materials, such as powders, foams, fibrous materials, and multilayer systems. Experimental data and correlations are reviewed, and a first principles-based correlation is proposed to estimate the dependence of effective conductivity on various factors. The proposed correlation is validated using available experimental data and further improvements and testing are discussed.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Energy & Fuels
Daulet Magzymov, Ram R. Ratnakar, Birol Dindoruk, Russell T. Johns
Summary: This research evaluates the application of machine learning in flow and transport in porous media, examining its reliability and applicability in predicting the physical behavior. The study shows that a physics-informed machine learning algorithm can capture the flow physics and its effects on key features, and can be utilized to solve inverse problems for parameter estimation.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2022)
Article
Engineering, Chemical
Ram R. Ratnakar, Mingjie Tu, Vemuri Balakotaiah
Summary: In this paper, a novel method based on the coupling of ROM and domain decomposition method for multi-component systems is proposed and validated. It simplifies the evaluation of transfer coefficients, makes them independent of other factors and reaction parameters, and significantly speeds up simulations. This approach is of great significance for real-time control of reactors.
CHEMICAL ENGINEERING SCIENCE
(2023)
Article
Energy & Fuels
Ram R. Ratnakar, Vivek Chaubey, Birol Dindoruk
Summary: In this study, a machine learning based workflow was developed to estimate the solubility of CO2 in brine under different salt mixtures, pressure, and temperatures. Extensive experimental observations were used to test the performance of predictive models and workflow, and key features of brine components with significant contributions were identified.
Article
Engineering, Petroleum
Birol Dindoruk, Ram R. Ratnakar, Sanyal Suchismita
Summary: This study focuses on thermodynamic modeling and pH measurements of acid-gases, water, and hydrocarbons in fluid systems replicating sour fields, to evaluate top-of-line corrosion and wellbore integrity. The results show that the wellbore can experience low pH levels, and the model developed can be extended to support various sour systems and facilities. Sensitivity analysis can also be performed to assess the impacts of different factors on pH prediction.
Article
Engineering, Chemical
Qing Han, Mengqing Shi, Linkai Han, Di Liu, Mingwei Tong, Yuxin Xie, Zhonghua Xiang
Summary: Developing highly efficient bifunctional oxygen electrocatalysts is crucial for zinc-air flow batteries. Metal-organic frameworks (MOFs) and covalent organic polymers (COPs) have emerged as promising alternatives due to their designable and controllable atomic-level structures. However, their catalytic performances are limited by conductivity and catalytic activity. In this study, nanosheet FeNi-MOF and iron phthalocyanine rich COP hybrid materials are assembled through the pi-pi stacking effect to create highly efficient bifunctional electrocatalysts. The resulting catalyst exhibits superior catalytic performance and stability, making it a promising candidate for zinc-air flow batteries.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Daria Grigorash, Dmytro Mihrin, Rene Wugt Larsen, Erling H. Stenby, Wei Yan
Summary: The article introduces a new approach to describe the cross-association between molecules, allowing for the simulation of weakly bound molecular complexes with different conformations in mixtures. By incorporating this approach into the equation of state, accurate predictions of vapor-liquid equilibrium and liquid-liquid equilibrium can be made. The new method is validated through experiments on alcohol and acid mixtures, with the results compared to experimental data, demonstrating its accuracy and reliability.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Mohammed Al-Sharabi, Daniel Markl, Vincenzino Vivacqua, Prince Bawuah, Natalie Maclean, Andrew P. E. York, Axel Zeitler
Summary: This study used terahertz pulsed imaging to investigate the transport process of different solvents into ceramic catalytic materials. The results showed that the heating rate of the samples influenced the water transport rate, while the viscosity of 1-octanol slowed down its transport.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Chukwunonso Anyaoku, Sati Bhattacharya, Rajarathinam Parthasarathy
Summary: This study aimed to enhance understanding of settling dynamics in viscoelastic fluids by developing a semi-empirical correlation and a dimensionless ratio, which accurately described the characteristics of settling suspensions.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Antti I. Koponen, Janika Viitala, Atsushi Tanaka, Baranivignesh Prakash, Olli-Ville Laukkanen, Ari Jasberg
Summary: This study focuses on the development of foam application chemicals for the paper and board industry. The research explores the rheology of the polyvinyl alcohol foam used in the process. Measurements were conducted to determine the foam viscosity and slip flow. The results suggest that slip flow contributes significantly to the total flow rate, and the obtained viscosity and slip models provide a solid foundation for industrial processes.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Dalei Sun, Jinghui Cai, Yating Yang, Zhiwu Liang
Summary: In this study, Fe-doped alpha-Bi2O3 catalysts with different Fe/Bi molar ratios were synthesized and utilized in the carbonylation of isobutyl amine with CO2. The results showed that Fe doping significantly enhanced the catalytic abilities of alpha-Bi2O3.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Yuan Tian, Xinxin Wang, Yanrong Liu, Wenping Hu
Summary: This paper predicts the solubility of nitrogen gas in ionic liquids (ILs) using two quantitative structure-property relationship (QSPR) models. By combining machine learning methods and ionic fragments contribution method, the accuracy and reliability of the prediction models are improved.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Liwang Wang, Wei Liu, Pan Yang, Yulong Chang, Xiaoxu Duan, Lingyu Xiao, Yaoming Hu, Jiwei Wu, Liang Ma, Hualin Wang
Summary: This study investigates the effective phase interfacial area (ae) of hydro-jet cyclones at different injection angles. The results show that a 45 degrees upward incidence angle yields the most favorable flow field characteristics for efficient mass transfer. The significant enhancement in ae of the hydro-jet cyclones offers the advantage of reducing equipment volume and cost savings.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Chuanjun Wu, Jiangzhi Chen, Jiyue Sun, I-Ming Chou, Shenghua Mei, Juezhi Lin, Lei Jiang
Summary: In this study, the solubility of H2S hydrate in water was measured using Raman spectroscopy. The results showed that the solubility increases with temperature under certain equilibrium conditions, and the solubility also depends on pressure and temperature under different equilibrium conditions. A thermodynamic model based on the van der Waals-Platteeuw theory was developed to predict the solubility, demonstrating its accuracy.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Lorenzo Brivio, Serena Meini, Mattia Sponchioni, Davide Moscatelli
Summary: This study investigates the influence of three main parameters and proposes a kinetic model to predict the optimal operating conditions for high yield of dimethyl terephthalate (DMT) in the chemical recycling process of polyethylene terephthalate (PET).
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Hongju Lin, Fanhui Liao, Yanchang Chu, Mingyu Xie, Lun Pan, Yuanyuan Wang, Lijian Leng, Donghai Xu, Le Yang, Gangfeng Ouyang
Summary: A honeycomb NiCo/C-Na catalyst with a micro-meso-macroporous structure has been fabricated and shown to have significantly higher catalytic activity for the decarboxylation of fatty acids. It also proves to be efficient in upgrading sludge HTL bio-crude, resulting in a biofuel with decreased viscosity and increased density.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Xiaoxian Li, Rui Li, Min Lin, Mingde Yang, Yulong Wu
Summary: A series of coated non-noble metal porous carbon catalysts were synthesized and applied to the aqueous-phase deoxygenation of algal bio-oil. One of the catalysts showed excellent deoxygenation selectivity and catalytic activity at 250 degrees C. The catalyst exhibited good hydrothermal stability and the reaction mechanism was proposed based on product analysis and active site analysis.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
M. V. Chudakova, M. V. Popov, P. A. Korovchenko, E. O. Pentsak, A. R. Latypova, P. B. Kurmashov, A. A. Pimenov, E. A. Tsilimbaeva, I. S. Levin, A. G. Bannov, A. V. Kleymenov
Summary: A series of catalysts with different potassium contents were prepared using solution combustion synthesis and characterized using various techniques. The results showed that the potassium content affected the phase composition and texture of the catalysts. The addition of a small amount of potassium resulted in a change in particle size distribution, leading to higher hydrogen yield. The Ni-1%K2O/Al2O3 catalyst exhibited the highest hydrogen yield at temperatures of 675 and 750 degrees Celsius.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Aliakbar Roosta, Nima Rezaei
Summary: In this study, we modified the electrolyte cubic plus association equation of state (e-CPA EoS) and integrated it with two electrical conductivity models to estimate the electrical conductivity of 11 monovalent electrolyte solutions in water. The modified e-CPA model demonstrated better performance and the hybridization with electrical conductivity models resulted in two predictive models for estimating the electrical conduction of dilute and concentrated electrolyte solutions. These predictive models showed relative average percentage deviations (AARD) of 11.15% and 13.87% over wide ranges of temperature and electrolyte concentration.
CHEMICAL ENGINEERING SCIENCE
(2024)
Article
Engineering, Chemical
Haoren Niu, Jianzheng Wang, Qingzhu Jia, Qiang Wang, Jin Zhao, Fangyou Yan
Summary: A study developed two quantitative structure-property relationship models for the complexation performance of alpha- and beta-cyclodextrins and validated their stability and predictive ability through internal and external validation. The models showed robustness and satisfactory performance, as demonstrated by the experimental results and model validations. These models can effectively predict the binding constants between cyclodextrins and various types of molecules, providing valuable tools for cyclodextrin design.
CHEMICAL ENGINEERING SCIENCE
(2024)
