Article
Engineering, Chemical
Yue Qiu, Suyang Zhou, Jinyi Chen, Zhi Wu, Qiteng Hong
Summary: This paper investigates the effects of intermittent and fluctuating green hydrogen produced by different types of renewable energy on the dynamic distribution of hydrogen concentration after blending into natural gas pipelines. Two convection-diffusion models for dynamic simulation of hydrogen injections are proposed. The simulation results indicate that all pipelines can work under safe conditions in the wind-power-dominated scenario.
Article
Thermodynamics
S. Molina, R. Novella, J. Gomez-Soriano, M. Olcina-Girona
Summary: Hydrogen substitution in compressed natural gas applications is a potential alternative for fossil fuels, contributing to the shift towards a hydrogen economy. This research focuses on examining the adoption of hydrogen as a fuel for light-duty transportation, evaluating its performance and emissions in a spark-ignition engine using natural gas-based fuel blend. Findings highlight the importance of adjusting the air dilution rate and engine operation parameters to optimize performance and control pollutant emissions as the percentage of hydrogen increases. Moreover, the study identifies the threshold for hydrogen substitution, beyond which the reduction of carbon dioxide emissions becomes significant compared to the reduction of carbon content in the fuel blend.
ENERGY CONVERSION AND MANAGEMENT
(2023)
Article
Thermodynamics
Rajesh Kumar Prasad, Avinash Kumar Agarwal
Summary: Experimental studies comparing HCNG and H-2 enriched CNG fuel in SI and LI modes showed that HCNG achieved a maximum thermal efficiency of 42.8% in LI mode. Additionally, BSHC emissions were consistently lower in LI mode compared to SI mode.
Article
Engineering, Chemical
Xinhui Song, Zhengwei Qu, Jianan Kou, Yunjing Wang, Popov Maxim Georgievitch
Summary: This paper presents a new model for incorporating hydrogen into natural gas pipelines to minimize the sum of wind curtailment cost, operation cost, and carbon emission cost. The results of the model show that considering HCNG can reduce the total cost of the environmental economic dispatch of the EGIES by about 34.1%.
Article
Green & Sustainable Science & Technology
Jianan Ye, Min Xie, Shiping Zhang, Ying Huang, Mingbo Liu, Qiong Wang
Summary: In this study, a novel HBGT model is developed to reflect the influence of hydrogen blending on the operation performance of HBGTs. The model can describe the carbon emission and co-combustion power generation properties of HBGTs, and can be applied to solve the carbon emission and renewable energy source consumption problems of electricity-HCNG UIESs. The simulation results demonstrate that the proposed HBGT modeling method has low-carbon economy and offers accurate operation performance. HBGT power generation can reduce the carbon emissions of an electricity-HCNG UIES by 22.62%, while improving the economy and wind power consumption.
Article
Chemistry, Physical
Davide Adinolfi, Michela Costa, Adolfo Palombo, Daniele Piazzullo
Summary: This paper presents a numerical study and optimization of a cogeneration plant installed in an industrial site, focusing on seasonal storage of hydrogen to meet energy needs and reduce environmental impact. Two alternatives are analyzed, and the dynamic response and economic analysis are conducted to evaluate their performance.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Energy & Fuels
Yue Qiu, Suyang Zhou, Wei Gu, Yuping Lu, Xiao-Ping Zhang, Gaoyan Han, Kang Zhang, Hongkun Lyu
Summary: This paper investigates the effects of hydrogen-enriched compressed natural gas (HCNG) on the dynamics of the gas network and proposes an improved model for the HCNG network. It also introduces an optimal dispatch model for the electricity-HCNG-integrated energy system (E-HCNG-IES) considering the HCNG supply chain. The proposed methodology is evaluated through numerical testbeds, demonstrating the economic and environmental benefits of increasing hydrogen volume fraction in the E-HCNG-IES.
CSEE JOURNAL OF POWER AND ENERGY SYSTEMS
(2023)
Article
Energy & Fuels
Anas Rao, Ziru Wu, Roopesh Kumar Mehra, Hao Duan, Fanhua Ma
Summary: The main pollution source of petrochemical products can be controlled by the implementation of hydrogen fuel in the transportation sector. Experiments on gas engines with different hydrogen percentages, EGR rates, and spark timings have been conducted to analyze the performance and emissions of compressed natural gas engines under various conditions. The analysis shows that optimal mixtures of hydrogen fractions and EGR ratios can be determined for different load conditions.
Article
Chemistry, Physical
Mhadi A. Ismael, A. Rashid A. Aziz, Salah E. Mohammed, A. Ezrann Z. Zainal, Masri B. Baharom, Ahmed T. Raheem, Wasiu B. Ayandotun, Farith Ikmal Harith, Intan Khazaimah
Summary: The addition of hydrogen into CNG improves the combustion stability and efficiency of the FPLG engine, reduces the impact of injection position, and increases power output.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2021)
Article
Chemistry, Physical
Abbas Zarenezhad Ashkezari
Summary: Increasing the compression ratio can reduce fuel consumption and improve performance. The optimal compression ratio is important in engine design, and the VCR strategy can optimize the performance and emissions of bi-fuel engines.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Energy & Fuels
Yimin Deng, Raf Dewil, Lise Appels, Flynn Van Tulden, Shuo Li, Miao Yang, Jan Baeyens
Summary: Natural gas, being a major fuel source, is being researched for its potential to be partially decarbonized through the production of hydrogen. The thermo-catalytic decomposition of CH4 into H-2 and C is gaining interest as a promising technology. Cheaper and more efficient catalysts are being investigated for this process.
Article
Energy & Fuels
Rajesh Kumar Prasad, Avinash Kumar Agarwal
Summary: The study converted a single-cylinder diesel engine into a supercharged spark ignition/laser ignition gaseous fuel engine, using different HCNG mixtures for experiments. It was found that at optimum boost, laser ignition mode increased engine torque, reduced maximum peak in-cylinder pressure, improved brake thermal efficiency, lowered fuel consumption, and decreased emissions.
Article
Chemistry, Physical
Wendi Zheng, Jihui Li, Kebo Lei, Zhenguo Shao, Jiurong Li, Zhihong Xu
Summary: This paper proposes an optimal dispatching method for hydrogen-rich compressed natural gas (HCNG) penetrated integrated energy system (HPIES) by comprehensively modeling the injection, transmission, and separation processes of HCNG. The method utilizes an HCNG mass flow rate model considering variable mixing ratio and unknown beginning flow direction, as well as a hydrogen separation model using a combined membrane and pressure swing adsorption separation process. The tightening McCormick algorithm is used to quickly solve the HPIES optimal dispatch problem with satisfactory feasibility check. Case studies validate the effectiveness of the algorithm and model, with an average error of 0.031% for the bilinear term constraint.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Energy & Fuels
Anas Rao, Hongyang Gao, Fanhua Ma
Summary: The study investigates the utilization of hydrogen fuel in internal combustion engines and proposes various laminar burning speed correlations for HCNG fuel mixtures. The effect of Exhaust Gas Recirculation (EGR) on the laminar burning speed is also explored, with a new correlation developed to improve the quasi-dimensional combustion model. The GRI Mech3.0 mechanism is employed for predicting laminar burning speeds under different operating conditions, showing promising results for HCNG fuel mixtures.
Article
Chemistry, Physical
Esenay Arslan, Nafiz Kahraman
Summary: Natural gas, an alternative fuel, has been widely used in transportation due to its economic and environmental advantages. While it is commonly used in spark ignition engines, its application in compression ignition engines has been limited due to combustion issues. However, the addition of hydrogen to natural gas can enhance its combustion properties in compression ignition engines.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Thermodynamics
Yanyu Qiao, Zhichao Chen, Zheng Yu, Guan Shuo, Jiawei Li, Zhenhua Yuan, Lingyan Zeng, Zhengqi Li
Summary: The combustion characteristics of pyrolytic semi-coke (SC) were studied by analyzing its physical and chemical properties. It was found that SC has a larger specific surface area, pore volume, and fractal dimension compared to anthracite. The main combustion stage of SC consists of fixed carbon combustion and CaCO3 decomposition, and it has a lower ignition temperature than anthracite.
COMBUSTION SCIENCE AND TECHNOLOGY
(2023)
Article
Thermodynamics
Jia Xing Liu, Hang Guo, Fang Ye, Chong Fang Ma
Summary: This paper investigates the electrical performance changes during continuous mode switching between fuel cell and electrolytic modes through experimental research. It is found that the voltage slightly decreases during mode switching, and the two-phase flow phenomenon is similar in different modes. Bubbles are generated and water is consumed in electrolytic mode, while liquid water gathers in the fuel cell mode. The cycle test results show that the voltage of both electrolytic cell and fuel cell decreases periodically, especially under high current density.
INTERNATIONAL JOURNAL OF GREEN ENERGY
(2023)
Article
Chemistry, Organic
Jia-Bao Liu, Sunny Kumar Sharma, Vijay Kumar Bhat, Hassan Raza
Summary: This paper investigates two chemical structures and computes their multiset dimension and mixed metric dimension. The mixed metric dimension refers to the cardinality of the minimum set of elements that can distinguish different elements in chemical structures through recognition.
POLYCYCLIC AROMATIC COMPOUNDS
(2023)
Article
Engineering, Electrical & Electronic
Lijuan Zhang, Jiajun Liu, Dongming Li, Jinyuan Liu, Xiangkun Liu
Summary: In this paper, a segmentation network called MSAA-Net, which combines multi-scale features and an improved attention-aware U-Net, is proposed. The architecture improves the performance of U-Net and reduces computational costs by extracting features of different scales on a single feature layer and performing attention perception in the channel dimension.
SIGNAL IMAGE AND VIDEO PROCESSING
(2023)
Review
Materials Science, Multidisciplinary
Jun-Jie Wu, Hanfei Gao, Xue-Dong Wang, Yuchen Wu, Lei Jiang, Liang-Sheng Liao
Summary: This article reviews the recent advances of near-infrared (NIR) organic micro/nanolasers on nondoped molecule aggregates, covering the aspects of gain materials, fabrication of self-assembled microcavities, NIR lasing actions, and applications. The article aims to offer valuable insights for further development of high-performance NIR organic micro/nanolasers.
ADVANCED OPTICAL MATERIALS
(2023)
Article
Chemistry, Physical
Zhe An, Jiayu Liu, Meng Cao, Jian Zhang, Yanru Zhu, Hongyan Song, Xu Xiang, Jing He
Summary: This study reports a highly efficient one-pot conversion method from ethanol to DEE, achieving high ethanol conversion and DEE selectivity using a Bi/BiCeOx bifunctional catalyst. Efficient catalysis is achieved on the interfacial Bi delta+-O-v-Ce-III sites through strong metal-support interaction.
Article
Chemistry, Physical
Tiankai Chen, Jiali Li, Pengfei Cai, Qiaofeng Yao, Zekun Ren, Yixin Zhu, Saif Khan, Jianping Xie, Xiaonan Wang
Summary: Rapid and accurate chemical composition identification is crucial in chemistry. Optical absorption spectrometry has limitations in identifying complex chemical compositions, especially in nano-scale research. In this study, a machine-learning-based method is developed to identify the compositions of metal nanoclusters (NCs) from featureless spectra. The method achieves good matches and low error values on optical absorption spectra that are difficult for humans to interpret. This work opens up possibilities for precise identification of nanomaterials based on their optical properties.
Article
Engineering, Environmental
Francielle C. F. Marcos, Raphael S. Alvim, Lili Lin, Luis E. Betancourt, Davi D. Petrolini, Sanjaya D. Senanayake, Rita M. B. Alves, Jose M. Assaf, Jose A. Rodriguez, Reinaldo Giudici, Elisabete M. Assaf
Summary: The role of copper crystallization in enhancing methanol production via CO2 hydrogenation over CuZrO2 catalysts was investigated using a combination of experimental and computational studies. It was found that the intermediate steps of the catalyzed reaction might depend on the incorporation of copper in the zirconia sample. Catalysts containing only amorphous interfacial sites showed higher activity in the CO2-to-methanol hydrogenation process compared to catalysts with high crystallinity of copper.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Environmental
Jun Yin, Jiali Li, Iftekhar A. Karimi, Xiaonan Wang
Summary: Modeling is crucial for reactor or process design, control, and optimization, but developing high-fidelity mechanistic models for complex reactor systems is time-consuming. Machine learning models using data-driven methods can fill the gap between complex systems and limited knowledge. This research presents a machine learning model architecture specifically for dynamic modeling of general flow reactors, achieving higher model accuracy, data efficiency, and model interpretability than commonly used models.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Junwei Zheng, Qian Ding, Aina He, Yaqiang Dong, Lei Xie, Xubin Li, Xincai Liu, Jiawei Li
Summary: Fe-Si-B-Cu-Nb nanocrystalline ribbons with increased annealing process window and insensitivity to impurities and surface-crystallized layer were successfully prepared using industrial raw materials.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Polymer Science
Jicheng Wang, Luotao Zhang, Haibin Hu, Jiawei Li, Dongming Qi
Summary: The morphology of nanofibrils in composite fibers can be manipulated by controlling the crosslinking network structure of the dispersed phase. The heterogeneity of the crosslinking network can lead to smaller diameter nanofibrils, resulting in increased tensile strength and toughness of the composite fibers.
JOURNAL OF APPLIED POLYMER SCIENCE
(2023)
Article
Environmental Sciences
Xiaoyang Yang, Dongsheng Ji, Jiawei Li, Jun He, Chongshui Gong, Xiaojuan Xu, Zhe Wang, Yu Liu, Fang Bi, Zhongzhi Zhang, Yunbo Chen
Summary: Limited by the scarcity of in situ vertical observation data, the influences of biomass burning in Southeast Asia on major atmospheric carbonaceous compositions in downwind regions have not been thoroughly studied. Aircraft observations were conducted to obtain vertical distributions of black carbon (BC), carbon monoxide (CO), and carbon dioxide (CO2). Four types of profiles were identified. Simulations showed that considering the vertical BC distribution is crucial in estimating the radiative forcing (RF) and heating rate (HR) caused by BC.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Fu Yanwen, Zhao Guojing, Dai Wenqian, Wang Yue, Li Jiawei, Tan Mengyu, Li Yan, Liu Haoran, Xie Bing, Jin Xiao, Fan Enyu, Zhao Lulu, Cao Jian, Yue Lei, Wu Chenghao, Chen Yongfeng, Chen Guoqiang, Zhang Yong, Luo Kezi, Yang Haitao, Han Xuemei, Ge Jianping, Zhu Jun, Feng Limin
Summary: The Chinese Loess Plateau has been severely impacted by anthropogenic activities, leading to minimal leopard sightings in recent decades. However, a recent discovery shows that the leopard population is recovering, offering hope for biodiversity conservation in human-dominated landscapes. By applying the concept of ecological networks, researchers identified key factors promoting leopard restoration and found that the connectivity of these networks positively influenced leopard survival. This study highlights the effectiveness of establishing ecologically connected habitats and the importance of using ecological networks for conservation planning in fragmented ecosystems.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Economics
Jiaming Liu, Chengzhang Li, Peng Ouyang, Jiajia Liu, Chong Wu
Summary: Financial distress prediction is crucial in the fintech field. This study utilizes tree-based gradient boosting models to predict financial distress for Chinese listed companies. The results show that these models have better predictive performance and provide insights on the significant relationships between financial indicators and financial distress.
JOURNAL OF FORECASTING
(2023)
Article
Computer Science, Artificial Intelligence
Xiang Shi, Yinpeng Liu, Jiawei Liu, Qikai Cheng, Wei Lu
Summary: Scientific papers are crucial for academic communication, but many of them lack in-depth research and present core content ambiguously, hindering the progression of science and technology. To address this challenge, the INTEGrity vERification (INTEGER) task is introduced to help researchers assess the integrity of their papers and verify the clarity of each knowledge unit. A multi-task learning model utilizing Tucker decomposition and span-level attention mechanism is proposed to accurately identify terms and their integrity. Experimental results show the effectiveness of the model.
EXPERT SYSTEMS WITH APPLICATIONS
(2024)