Article
Engineering, Environmental
Changkai Zhou, Ke Zhou, Huan Li, Xiang Xu, Baogen Liu, Hailong Li, Zheng Zeng, Weiwu Ma, Liqing Li
Summary: The study explores the application of pressure swing adsorption (PSA) for removing and recycling VOCs, with a focus on nonequilibrium time, effective length, and enrichment ratio. Various experiments were conducted to investigate the mechanism and industrial parameters of PSA, revealing that factors such as kinetic diameter, polarity, pore size, and boiling point influence the efficiency of VOCs removal. Methanol and acetone showed shorter effective lengths for complete removal compared to toluene, and the desorption performance was found to be related to desorption activation energy and the boiling point of the adsorbate. Ultimately, the study found that acetone had the highest recovery ratio among the three VOCs studied, presenting new opportunities for VOCs removal and recovery.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Energy & Fuels
Xinxin Liu, Qingzhao Li, Guiyun Zhang, Xu Ma, Pengfei Zhu, Xiaowen Li
Summary: By comparing coal samples with different degrees of metamorphism, it was found that the oxygen binding ability of coal molecules is highest at 200℃ under dry-air conditions. The dry-air oxidized precursors activated by KOH exhibit excellent adsorption properties.
Article
Thermodynamics
Sai Yagnamurthy, Dibakar Rakshit, Sanjeev Jain, Bidyut Baran Saha
Summary: This study evaluates the cooling potential of novel activated carbon-based pairs with R32 refrigerant for adsorption cooling systems. The composition with the highest volumetric cooling energy and thermal conductivity is considered for performance evaluation. Numerical analysis of two finned tube heat exchanger design configurations shows that the longitudinal fin configuration has a higher coefficient of performance with minimal decrement in cooling power. The results indicate the significance of heat exchanger optimization and offer better cooling capacities and compact designs compared to other HFC-based studies.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2023)
Article
Chemistry, Multidisciplinary
Zekai Miao, Guofeng Qiu, Xu Zhao, Fanhui Guo, Yixin Zhang, Jianjun Wu
Summary: This study explored the use of coal gasification fine slag-based activated carbons for CO2 capture, demonstrating that pre-oxidation treatment with various agents can enhance the CO2 adsorption capacity by improving the pore structure. The results highlighted the importance of oxygen-containing groups in determining the surface area of activated carbons, with O-C = O groups playing a key role and C = O groups potentially impeding pore development.
JOURNAL OF CO2 UTILIZATION
(2021)
Article
Engineering, Chemical
Kaiqiang Zhang, Zhijun Jin, Gensheng Li, Quanyou Liu, Leng Tian
Summary: Understanding gas adsorptions in porous media is crucial for academic research and industrial applications. This study specifically investigates the adsorption of methane and carbon dioxide on different minerals and evaluates their effects on reservoir productions and carbon storage processes.
SEPARATION AND PURIFICATION TECHNOLOGY
(2023)
Article
Chemistry, Applied
Ismahene Ben Khemis, Fatma Aouaini, Lamies Bukhari, Samia Nasr, Abdelmottaleb Ben Lamine
Summary: An advanced monolayer adsorption model was used to study the adsorption of four vanilla odorants on a mouse eugenol olfactory receptor. The results showed that the odorants were adsorbed in a non-parallel orientation and the adsorption process was multimolecular. The adsorption energy values suggested that the odorants were physisorbed and the adsorption mechanism was exothermic. The estimated parameters can be used to quantify the interactions between the odorants and the olfactory receptor.
Article
Green & Sustainable Science & Technology
M. Vorokhta, J. Novakova, M. Dopita, I. Khalakhan, V. Kopecky, M. Svabova
Summary: This study demonstrates that the microporosity of three-dimensionally ordered micromesoporous carbon (3DOmm) can be increased by physical activation, leading to improved CO2 capture performance. The activated 3DOmm carbon exhibits a highly porous amorphous structure with increased micropore and mesopore volumes and a higher specific surface area. Furthermore, the activated 3DOmm carbon shows excellent CO2 adsorption performance over a wide pressure range, with fast kinetics and high selectivity for CO2 over N2.
MATERIALS TODAY SUSTAINABILITY
(2023)
Article
Thermodynamics
Sai Yagnamurthy, Dibakar Rakshit, Sanjeev Jain, Kaiser Ahmed Rocky, Md. Amirul Islam, Bidyut Baran Saha
Summary: This study investigates the cooling performance of Maxsorb-III activated carbon composites synthesized with the additives of H25 Graphene nanoplatelets, 1-Hexyl-3-methylimidazolium bis(trifluormethylsulfonyl)imide ionic liquid with polyvinyl alcohol for R32 refrigerant-based adsorption cooling applications. The kinetic characteristics and heat of adsorption assessments are evaluated, and a holistic comparison of the cooling performances of the composites is proposed.
APPLIED THERMAL ENGINEERING
(2022)
Article
Chemistry, Multidisciplinary
Yongxiang Niu, Chao Zheng, Yucong Xie, Kai Kang, Hua Song, Shupei Bai, Hao Han, Shunyi Li
Summary: Given the characteristics and risks of ammonia, the removal of ammonia is crucial for industrial production and environmental safety. This study modified viscose-based activated carbon fiber (ACF) with nitric acid impregnation to enhance its adsorption capacity for ammonia. The results showed that ACF-N-6 significantly increased the surface functional group content without destroying the physical structure of the activated carbon fibers. The highest adsorption capacity of ammonia by ACFs was 14.08 mmol/L at 293 K, which was a 165% increase compared to ACF-raw. The adsorption performance was strongly correlated with the carboxyl group content and relative humidity of the inlet gas. This research contributes to the development of efficient ammonia adsorption systems for industrial production and environmental safety.
Review
Green & Sustainable Science & Technology
Al Ibtida Sultana, Nepu Saha, M. Toufiq Reza
Summary: Hydrogen (H-2) is considered a potential cost-efficient clean fuel due to its high energy content and sustainability. However, transportation and storage of H-2 remain major challenges for a sustainable H-2 economy. Developing biomass-based activated carbons as effective H-2 storage materials has been emphasized as a way to address these challenges.
Article
Materials Science, Multidisciplinary
Wei Zhu, Weijin Qian, Ruizi Liu, Weijun Huang, Haijun Luo, Changkun Dong
Summary: Investigated the FEED properties of MWNT emitter in hydrogen and nitrogen environments. Found that gas adsorption can reduce the work function and shift the FEED peaks. The amount of spectrum displacements increased with higher gas partial pressures. The double peak spectra imply emission electrons from different carbon structures. Meanwhile, high carbon content was detected in the vacuum.
Article
Engineering, Environmental
Catarina Helena Pimentel, Lidia Diaz-Fernandez, Diego Gomez-Diaz, Maria Sonia Freire, Julia Gonzalez-Alvares
Summary: Reducing the harmful impacts of CO2 emissions and greenhouse effect on climatic conditions is necessary. In this study, biochar and activated carbons were produced and characterized. The activated carbon activated at 600 degrees C with KOH at a ratio of 1:4 w/w showed the highest CO2 adsorption capacity and selectivity.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2023)
Article
Chemistry, Physical
Drew M. Glenna, Asmita Jana, Qiang Xu, Yixiao Wang, Yuqing Meng, Yingchao Yang, Manish Neupane, Lucun Wang, Haiyan Zhao, Jin Qian, Seth W. Snyder
Summary: This article introduces an AC-based material and proposes a hierarchical guideline for evaluating the feasibility of such materials in carbon capture. The most critical performance indicator is the CO2 adsorption energy, with considerations for thermal stability and defect sensitivity, as well as selectivity and capacity.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Engineering, Multidisciplinary
Hanaa Mohamed Said, Annunziata D'Orazio, S. Mohammad Sajadi, Mustafa Inc
Summary: Industrial wastewater treatment is a concern for governments and environmental experts. The pollution mainly comes from organic pollutants like dyes, halogenated hydrocarbons, and phenolic compounds. Phenol is widely used in various industries. In this study, Molecular Dynamics simulation was used to investigate the adsorption of phenol molecules by carbon nanostructures and nitrogen and bromine modified carbon nanostructures. BCN-graphene was found to be the most effective nanostructure for removing phenol molecules from the water, having the highest adsorption energy and greater stability. This research opens up possibilities for using bromine nitride structures in petroleum wastewater treatment.
ENGINEERING ANALYSIS WITH BOUNDARY ELEMENTS
(2023)
Article
Chemistry, Multidisciplinary
Sangwon Seo, Frantisek Miksik, Yuta Maeshiro, Kyaw Thu, Takahiko Miyazaki
Summary: This study evaluated the performance of low Global Warming Potential refrigerant R1234yf on activated carbon for adsorption heating applications. The adsorption isotherms were measured and compared with R134a, showing a 12% lower adsorption capacity. The coefficient of performance (COP) for the selected pair varied depending on the heat source temperature.
APPLIED SCIENCES-BASEL
(2021)
Article
Automation & Control Systems
Difan Tang, Lei Chen, Zhao Feng Tian, Eric Hu
Summary: This study proposes a modified value-function-approximation (MVFA) method for optimal control synthesis for continuous-time nonlinear systems, using neural networks for synchronous policy iteration. The approach employs gradient-descent tuning to adjust critic NN parameters, ensuring closed-loop system stability.
INTERNATIONAL JOURNAL OF CONTROL
(2021)
Article
Acoustics
Difan Tang, Lei Chen, Zhao F. Tian, Eric Hu
Summary: This study proposed a novel optimal neural-network control approach to improve airfoil active flutter suppression under control-input constraints by solving the Hamilton-Jacobi-Bellman equality online and integrating control-input constraints using a generalized nonquadratic cost function. The proposed method effectively improved airfoil active flutter suppression, as demonstrated theoretically and experimentally.
JOURNAL OF VIBRATION AND CONTROL
(2021)
Review
Materials Science, Multidisciplinary
Riaz Ahamed, Reza Ghomashchi, Zonghan Xie, Lei Chen
Summary: Ni-Mn-X Heusler alloys show multiferroic effects and have potential applications in actuation, magnetic refrigeration, and waste heat conversion. The magnetostructural coupling depends on alloy compositions and accurate characterization of crystal structures is crucial, with XRD, TEM, and DSC being important techniques for microstructural characterization.
CRITICAL REVIEWS IN SOLID STATE AND MATERIALS SCIENCES
(2021)
Article
Engineering, Civil
Xiao-xuan Du, Wei Zeng, Martin F. Lambert, Lei Chen, Eric Jing Hu
Summary: This paper presents an approach for pipe burst detection, localization, and cross-sectional area quantification based on changes in the discrete harmonic spectrogram and analysis of damping of fluid transients. The developed pressure signal processing algorithm allows for real-time data monitoring with lower data transmission and sampling rates compared to commonly used data acquisition systems. The algorithm has been verified both numerically and experimentally for its effectiveness in pipe burst detection.
JOURNAL OF WATER RESOURCES PLANNING AND MANAGEMENT
(2021)
Article
Energy & Fuels
Mingzhen Wang, Eric Hu, Lei Chen
Summary: This paper evaluates the energy-saving potential of applying a Thermal Diode Tank (TDT) in Refrigeration and Air-conditioning (RAC) systems. The study demonstrates that the COP of the TDT-assisted RAC system can be improved by 10~59% compared to the baseline system. Additionally, TDT-RAC systems with variable speed compressors can achieve greater energy savings than those with fixed speed compressors. Increasing the tank size can also enhance the energy-saving effect. A case study based on real weather data shows that TDT-RAC systems can save 9~40% energy on average every summer day.
Article
Thermodynamics
Samira Pourhedayat, Eric Hu, Lei Chen
Summary: Increasing compressor intake-air temperature adversely affects gas turbine performance and NOx emissions. Using absorption refrigeration and M-cycle technology as pre-coolers can efficiently lower the intake-air temperature, resulting in reduced energy consumption.
Article
Thermodynamics
Hamed Sadighi Dizaji, Eric Hu, Lei Chen, Samira Pourhedayat, Makatar Wae-hayee
Summary: This paper introduces the mini indirect evaporative cooler (MIEC) as a local cooling process for electronic units and investigates its cooling characteristics through experiments and theoretical studies. The results show that MIEC can effectively reduce the temperature of electronic units and improve efficiency under optimized conditions.
CASE STUDIES IN THERMAL ENGINEERING
(2021)
Article
Thermodynamics
Mingzhen Wang, Eric Hu, Lei Chen
Summary: This paper presents the development and validation of simulation models for a Thermal Diode Tank (TDT) with a Radiation-enhanced Heat Pipe (RTDT). The results show that the RTDT can generate colder water and has double the heat transfer capacity compared to the Convection TDT (CTDT). Increasing the heat pipe condenser area significantly enhances the performance of the TDT, especially for the RTDT.
INTERNATIONAL JOURNAL OF REFRIGERATION
(2023)
Article
Engineering, Civil
Xiao-xuan Du, Martin F. Lambert, Lei Chen, Eric Jing Hu
Summary: The purpose of this study was to illustrate the relationship between methods that utilize the damping of fluid transients and approaches based on frequency response diagrams and to discuss their applications in both leak and burst detection. The mathematical relationship between the two methods was revealed and verified numerically and experimentally. Additionally, a comparison was made between the two methods in terms of input signal bandwidth, problem type, low sampling rate capability, robustness, and real-time data monitoring capability, discussing their applicability in these aspects.
JOURNAL OF HYDRAULIC ENGINEERING
(2023)
Article
Thermodynamics
Samira Pourhedayat, Eric Hu, Lei Chen
Summary: This paper presents an improved validated semi-analytical gas turbine (GT) model that can simulate GT performance under various intake air conditions. The improved model overcomes three limitations of previous models by not assuming constant volumetric flow rate of intake air, constant output temperature of the combustion chamber (CC), and by evaluating the performance of the GT power plant directly from compressor intake air conditions. Deviations between model results and experimental data are less than 3%. Additionally, sensitivity analysis of both ambient conditions and GT characteristics is conducted as a sample application of the new model.
Article
Engineering, Civil
Xiao-xuan Du, Martin F. Lambert, Lei Chen, Eric Hu
Summary: The paper presents an approach for real-time pipe burst detection and location estimation based on changes in harmonics and damping analysis. Previous methods could not utilize higher order harmonics due to an increasing number of possible burst location solutions. However, the proposed algorithm overcomes this limitation and excludes incorrect solutions by analyzing damping. Additionally, real-time data analysis is made possible by setting the window gap between data windows. The approach has been verified numerically and experimentally with acceptable accuracy.
JOURNAL OF WATER RESOURCES PLANNING AND MANAGEMENT
(2023)
Review
Thermodynamics
Samira Pourhedayat, Eric Hu, Lei Chen
Summary: This paper provides a comprehensive review of pre-cooling strategies for gas turbine power plants from different viewpoints. Various technologies such as absorption refrigeration, direct evaporative cooling, fogging system, indirect evaporative cooling, vapor compression refrigeration, air-earth heat exchanger, iced thermal energy storage, turbo-expander system, liquefied natural gas system, and hybrid systems are discussed, taking into account climate conditions, type of gas turbine, and other factors. The strengths and weaknesses of each technology are clarified, and suggestions for different applications are provided along with research gaps and future directions.
THERMAL SCIENCE AND ENGINEERING PROGRESS
(2023)
Article
Energy & Fuels
Mingzhen Wang, Eric Hu, Lei Chen
Summary: This paper presents a novel technology to improve the energy efficiency of refrigeration and air-conditioning systems by applying a condenser cooling approach. By integrating an innovative thermal diode tank with the system, it is possible to lower the water temperature below the ambient temperature. The study shows that larger day/night ambient temperature differences and higher TS/Qc values can enhance the system's performance and energy saving percentage.
Proceedings Paper
Automation & Control Systems
Ahmad Hajeer, Lei Chen, Eric Hu
2020 IEEE 16TH INTERNATIONAL CONFERENCE ON AUTOMATION SCIENCE AND ENGINEERING (CASE)
(2020)
Article
Engineering, Civil
Xiao-xuan Du, Martin F. Lambert, Lei Chen, Eric Jing Hu, Wang Xi
JOURNAL OF HYDRAULIC ENGINEERING
(2020)
