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Your search keyword '"Hong, Zekai"' showing total 93 results
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93 results on '"Hong, Zekai"'

1. Islands on codim-2 branes in Gauss-Bonnet Gravity

Author

Li, Zhengjiang and Hong, Zekai

Subjects
High Energy Physics - Theory
Abstract

We study the black hole information problem on codim-2 branes in Gauss-Bonnet gravity. Thanks to the island surface ending on the brane, the Page curve of eternal black holes can be recovered for all of the GB couplings within the causal constraints. Our results strongly support the universality of the island mechanism. Similar to Einstein's gravity, the HM surface can exist only in a finite time in GB gravity. Remarkably, for various parameters, the maximum times of HM surface are always larger than the Page times. As a result, the strange behavior of HM surfaces does not affect the Page curves for general GB gravity. Finally, we establish the correlation between the Page time, GB couplings, and brane tension, revealing that the Page time increases with these factors., Comment: 19 pages,6 figures

Published
2023

8. A Review of Hydrogen Leak Detection Regulations and Technologies.

Author

Qanbar, Mohammed W. and Hong, Zekai

Subjects
*HYDROGEN detectors, *LEAK detection, *LEAK detectors, *CLEAN energy, *VALUE chains
Abstract

Hydrogen (H2) is positioned as a key solution to the decarbonization challenge in both the energy and transportation sectors. While hydrogen is a clean and versatile energy carrier, it poses significant safety risks due to its wide flammability range and high detonation potential. Hydrogen leaks can occur throughout the hydrogen value chain, including production, storage, transportation, and utilization. Thus, effective leak detection systems are essential for the safe handling, storage, and transportation of hydrogen. This review aims to survey relevant codes and standards governing hydrogen-leak detection and evaluate various sensing technologies based on their working principles and effectiveness. Our analysis highlights the strengths and limitations of the current detection technologies, emphasizing the challenges in achieving sensitive and specific hydrogen detection. The results of this review provide critical insights into the existing technologies and regulatory frameworks, informing future advancements in hydrogen safety protocols. [ABSTRACT FROM AUTHOR]

Published
2024
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21. Optimization of Micro Gas Turbine Based Hybrid Systems for Remote Off-grid Communities.

Author

Basmadjian, Nareg, Yun, Sean, and Hong, Zekai

Subjects
ELECTRIC power consumption, GAS turbines, COMMUNITIES, HYBRID systems, ENERGY consumption, HYBRID power systems, HYBRID zones, ECOLOGICAL impact
Abstract

Inherent fuel flexibility of micro gas turbine (MGT) makes the engine a promising energy solution to remote Canadian communities that are not connected to the North American electricity grid, where bio-oils derived from locally available bio-mass may be utilized to meet local power and heat demands to reduce fossil fuel consumption. The switch to bio-oils enabled by MGTs reduces not only carbon footprints but also operating expenses due to high transportation costs of fossil fuels. However, MGT efficiencies are greatly reduced at partial loads. This work investigates the feasibility of addressing MGT efficiency drops at partial loads by incorporating MGT with a Battery Energy Storage System (BESS) to form a hybrid system so that the MGT can be operated at near full power at all times for better efficiencies. In this study, a daily power demand profile of a typical Canadian household is adopted for optimizing battery size and MGT operating strategies. By optimizing MGT daily start time and the engine's threshold partial load factor, the specific fuel consumption and battery size can be minimized for a specific number of households on a micro-grid supported by the MGT-based hybrid power system. [ABSTRACT FROM AUTHOR]

Published
2023
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33. Resolving Discrepancies between State-of-the-Art Theory and Experiment for HO2+ HO2via Multiscale Informatics

Author

LaGrotta, Carly E., Meng, Qinghui, Lei, Lei, Barbet, Mark C., Hong, Zekai, and Burke, Michael P.

Abstract

Recent high-level theoretical calculations predict a mild temperature dependence for HO2+ HO2inconsistent with state-of-the-art experimental determinations that upheld the stronger temperature dependence observed in early experiments. Via MultiScale Informatics analysis of the theoretical and experimental data, we identified an alternative interpretation of the raw experimental data that uses HO2+ HO2rate constants nearly identical to theoretical predictions─implying that the theoretical and experimental data are actually consistent, at least when considering the raw data from experimental studies. Similar analyses of typical signals from low-temperature experiments indicate that an HOOOOH intermediate─identified by recent theory but absent from earlier interpretations─yields modest effects that are smaller than, but may have contributed to, the scatter in data among different experiments. More generally, the findings demonstrate that modern chemical theories and experiments have progressed to a point where meaningful comparison requires joint consideration of their data simultaneously.

Published
2023
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