| 1. |
- Huang, Jianqing, et al.
(författare)
-
A detailed study on the micro-explosion of burning iron particles in hot oxidizing environments
- 2022
-
Ingår i: Combustion and Flame. - : Elsevier BV. - 0010-2180. ; 238
-
Tidskriftsartikel (refereegranskat)abstract
- As a promising carbon-free fuel, iron powder can directly combust with air and has great potential to provide clean and high-grad heat for various applications. The combustion characteristics of iron particles are of great significance for developing iron combustion model, designing efficient combustor, and optimizing combustion technologies. In this work, the micro-explosion behavior of burning iron particles was experimentally investigated based on optical diagnostics. With two high-speed cameras operating at 10,000 frames per second, the three-dimensional (3D) motion and mean surface temperature of burning iron particles during the micro-explosion process were measured using the stereo imaging technique and two-color pyrometry, respectively. The probability of micro-explosions in different oxidizing environments were statistically studied. Three distinct micro-explosion modes have been observed. The results showed that the micro-explosion of burning iron particles heavily depended on oxygen concentration. The micro-explosion would slightly reduce the particle surface temperature by 30–70 K within 0.5 ms, since a lot of smaller fragments were produced. In addition, the 3D velocity of most fragments would sharply increase to 2–6 times within 0.2 ms after the micro-explosion occurred. Regarding the mechanism of the micro-explosion, three types of potential gas sources inside the particle were discussed. The sharp gradients of gas temperature and oxygen concentration may facilitate the rapid increase of the internal pressure in the particle, which eventually causes the micro-explosion.
|
|
| 2. |
- Xu, Shijie, et al.
(författare)
-
Phase change and combustion of iron particles in premixed CH4/O2/N2 flames
- 2024
-
Ingår i: Combustion and Flame. - 0010-2180. ; 259
-
Tidskriftsartikel (refereegranskat)abstract
- Metal powder is a promising carbon-free and recyclable energy carrier. Direct combustion of the micron-sized iron particles involves complex physical and chemical processes, such as heat transfer, surface reaction, and phase change. In this work, computational modelling of these processes is investigated and validated against experiments. A single iron particle combustion and phase change model is proposed in an Eulerian–Lagrangian framework. The new phenomenological model considers five stages, i.e., solid phase oxidation, melting of iron oxides and raw iron, liquid phase oxidation, cooling of liquid iron oxides, and solidification of super-cooled liquid iron oxides. The proposed model is first validated and then adopted in simulations of micron-sized iron particle combustion in premixed CH4/O2/N2 flames to study the effects of ambient temperature and oxygen concentration on single iron combustion. Results show that the new model is capable of replicating the melting, heterogeneous surface reaction, cooling, and solidification processes. Two-stage solidification is observed in experiments and modelled in simulations. This two-stage solidification includes a fast solidification with a significant temperature rise (∼150–200 K) and a thermal equilibrium solidification featuring a constant temperature and a slight particle radiant intensity decrease. In addition, a diffusion-controlled mechanism is identified during the melting process, in which the oxygen concentration dominates the melting time and the subsequent burning time. Furthermore, it is found that the reaction between iron and CH4/O2/N2 flame products, such as CO2 and H2O, plays a non-negligible role in the iron combustion process.
|
|
| 3. |
- Chen, Jian, et al.
(författare)
-
AXL promotes Zika virus infection in astrocytes by antagonizing type I interferon signalling
- 2018
-
Ingår i: Nature Microbiology. - : NATURE PUBLISHING GROUP. - 2058-5276. ; 3:3, s. 302-309
-
Tidskriftsartikel (refereegranskat)abstract
- Zika virus (ZIKV) is associated with neonatal microcephaly and Guillain-Barre syndrome(1,2). While progress has been made in understanding the causal link between ZIKV infection and microcephaly(3-9), the life cycle and pathogenesis of ZIKV are less well understood. In particular, there are conflicting reports on the role of AXL, a TAM family kinase receptor that was initially described as the entry receptor for ZIKV(10-22). Here, we show that while genetic ablation of AXL protected primary human astrocytes and astrocytoma cell lines from ZIKV infection, AXL knockout did not block the entry of ZIKV. We found, instead, that the presence of AXL attenuated the ZIKV-induced activation of type I interferon (IFN) signalling genes, including several type I IFNs and IFN-stimulating genes. Knocking out type I IFN receptor alpha chain (IFNAR1) restored the vulnerability of AXL knockout astrocytes to ZIKV infection. Further experiments suggested that AXL regulates the expression of SOCS1, a known type I IFN signalling suppressor, in a STAT1/STAT2-dependent manner. Collectively, our results demonstrate that AXL is unlikely to function as an entry receptor for ZIKV and may instead promote ZIKV infection in human astrocytes by antagonizing type I IFN signalling.
|
|
| 4. |
- Chen, Jian, et al.
(författare)
-
Zika virus infects renal proximal tubular epithelial cells with prolonged persistency and cytopathic effects
- 2017
-
Ingår i: Emerging Microbes & Infections. - : NATURE PUBLISHING GROUP. - 2222-1751. ; 6
-
Tidskriftsartikel (refereegranskat)abstract
- Zika virus (ZIKV) infection can cause fetal developmental abnormalities and Guillain-Barre syndrome in adults. Although progress has been made in understanding the link between ZIKV infection and microcephaly, the pathology of ZIKV, particularly the viral reservoirs in human, remains poorly understood. Several studies have shown that compared to serum samples, patients' urine samples often have a longer duration of ZIKV persistency and higher viral load. This finding suggests that an independent viral reservoir may exist in the human urinary system. Despite the clinical observations, the host cells of ZIKV in the human urinary system are poorly characterized. In this study, we demonstrate that ZIKV can infect renal proximal tubular epithelial cells (RPTEpiCs) in immunodeficient mice in vivo and in both immortalized and primary human renal proximal tubular epithelial cells (hRPTEpiCs) in vitro. Importantly, ZIKV infection in mouse kidneys caused caspase-3-mediated apoptosis of renal cells. Similarly, in vitro infection of immortalized and primary hRPTEpiCs resulted in notable cytopathic effects. Consistent with the clinical observations, we found that ZIKV infection can persist with prolonged duration in hRPTEpiCs. RNA-Seq analyses of infected hRPTEpiCs revealed a large number of transcriptional changes in response to ZIKV infection, including type I interferon signaling genes and anti-viral response genes. Our results suggest that hRPTEpiCs are a potential reservoir of ZIKV in the human urinary system, providing a possible explanation for the prolonged persistency of ZIKV in patients' urine.
|
|
| 5. |
- Jiao, Xingxing, et al.
(författare)
-
Highly Energy-Dissipative, Fast Self-Healing Binder for Stable Si Anode in Lithium-Ion Batteries
- 2021
-
Ingår i: Advanced Functional Materials. - : Wiley. - 1616-3028 .- 1616-301X. ; 31:3
-
Tidskriftsartikel (refereegranskat)abstract
- A double-wrapped binder has been rationally designed with high Young's modulus polyacrylic acid (PAA) inside and low Young's modulus bifunctional polyurethane (BFPU) outside to address the large inner stress of silicon anode with drastic volume changes during cycling. Harnessing the "hard to soft" gradient distribution strategy, the rigid PAA acts as a protective layer to dissipate the inner stress first during lithiation, while the elastic binder BFPU serves as a buffer layer to disperse residual stress, and thus avoids structural damage of rigid PAA. Moreover, the introduction of BFPU with fast self-healing ability can dynamically recover the microcracks arising from large stress, further ensuring the integrity of silicon anode. This multifunctional binder with smart design of double-wrapped structure provides enlightenment on enlarging the cycling life of high-energy-density lithium-ion batteries that suffer enormous volume change during the cycling process.
|
|
