Publications by authors named "Dehong Xia"

Recently, hydrothermal coliquefaction of biomass and plastic waste has attracted considerable research interest. However, there is a notable gap in understanding the fundamental reaction mechanisms between biomass and plastics during coliquefaction. This study focused on the coliquefaction of biomass model compounds and plastic polymers using ReaxFF molecular dynamics simulations under both subcritical and supercritical water conditions.

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Massive emission of CO as a potential driver of climate change has become a global issue presented in front of the whole human beings. Motivated by the CO cut-down requirement, China has aggressively undertaken restrictions aiming for peaking the carbon dioxide by 2030 and achieving carbon neutrality by 2060. However, due to the complex structures of industry and fossil fuel consumption in China, specific carbon neutrality route and the CO reduction potential are still open questions.

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Coliquefying synthetic aliphatic and aromatic polymer wastes using supercritical water has drawn considerable research attention. However, the mechanisms of chemical reactions between different types of polymers are ambiguous. Herein, depolymerization mechanisms for individual polymers and reaction mechanisms for binary polymer mixtures were investigated using molecular dynamics and density functional theory (DFT).

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For a country like China with unbalanced development pattern among provinces, domestic circulation (i.e., cross-province trade) is important for the long-term stability and prosperous development of economic market.

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Energy-related carbon emissions take a large proportion in China, and the interregional trade caused by provincial disparities has led to significant differences in carbon footprint (CF) and embodied carbon flows among provinces that make great bottlenecks for the balance of economic development and carbon mitigation. In this study, we developed an embodied carbon flow-based ecological network (ECFEN) model with economic trade and emission data through combining the multi-regional input-output model and ecological network analysis approach. The developed ECFEN model was applied to 30 provinces in China to quantify the interprovincial flow of carbon embodied in final goods and services and identify the ecological utility (competitive, exploitative, and exploited) and control/dependence relationships between different regions.

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The formation of a "critical nucleus" prior to phase change is a crucial step for new particle formation (NPF) in the atmosphere. However, the nucleation occurring below ∼1 nm is hard to observe directly. As an effective alternative, theoretical nucleation models have been widely studied.

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Quantifying the decoupling states of carbon emissions from a multi-sectoral and dual-perspective can guide more detailed emission reduction strategies. Based on the single-regional input-output (SRIO), Tapio decoupling analysis (TDA), and structural decomposition analysis (SDA), this study investigated the dynamic variation feature and decoupling state of multi-sectoral carbon emissions, and revealed their driving factors of consumption-based emissions in Guangdong province from 2002 to 2017. The main discovery can be summarized as follows from results analysis.

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Complete depolymerization of scrap tires (ST) to valuable oil products and fuel gas could be achieved by supercritical water (SCW) technology. For implementing this promising technology, migration mechanism of sulfur element during the entire ST-SCW depolymerization process was identified to reduce the sulfur pollutions. In the depolymerization process of ST, OH radicals released from SCW molecules could enhance cleavage of CS bonds, resulting sulfur-containing intermediates.

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In conventional lime calcination processes, because of fuel combustion in the kiln, the carbon dioxide (CO) from limestone decomposition is mixed with the flue gas, which results in energy requirement for gas separation in the carbon capture process. Here, a novel lime calcination system with carrier gas (CO) heating and air cooling is proposed to avoid the mixing problem of the CO and the flue gas. This system consists of a new shaft kiln with four processing zones and a furnace system, where fuel combustion, limestone reaction, and lime cooling are carried out separately.

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The growth of scrap tire (ST) has become an urgent environmental problem. In this work, the depolymerization process of ST in supercritical water (SCW) was studied with the ReaxFF molecular dynamic simulation. The depolymerization process and reaction pathway of ST in SCW were revealed.

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Aerosol particulate matter with dynamic diameter smaller than 2.5 μm (PM) is the main cause for haze pollution in China. As a dominant precursor of PM, SO emitted from industrial process is now strictly controlled by using limestone/gypsum Wet Flue Gas Desulfurization (WFGD) system in China.

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The purpose of this study is to provide scientific guidance for the morphological control of nanoparticle synthesis using the gas phase method. A universal thermodynamics model is developed to predict the morphology of nanoparticles fabricated using the inert gas condensation method. By using this model, the morphologies of aluminum nanocrystals are predicted under various preparation conditions.

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Secondary new particle formation (NPF) plays a significant role in atmospheric particulate matters (e.g., PM2.

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The aim of this article was to investigate the effect of ambroxol on radiation lung injury and the expression of transforming growth factor beta(1) (TGF-beta(1)), as well as tumor necrosis factor alpha (TNF-alpha) in plasma. Totally, 120 patients with locally advanced lung cancer in radiotherapy were randomized into treatment and control groups. Patients in the treatment group took ambroxol orally at a dosage of 90 mg, three times per day for 3 months from the beginning of radiotherapy.

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