| 1. |
- León, Felipe
(författare)
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Yishi zhexue he shenjingkexue
- 2024
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Ingår i: Philosophical Analysis. ; 15:4, s. 186-195 + 199
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Tidskriftsartikel (refereegranskat)abstract
- 摘 要:从哲学角度对当前的意识研究工作进行概述，可以证明哲学的做法 在意识研究中仍然具有持续的影响作用。在对有关意识和物质之间关系的一些主 要哲学立场进行讨论后，可以发现许多学者关注的意识问题——“身—心”问题或“心—脑”问题——只是意识研究中的几个问题之一。讨论“意识”“自我意识”和 “自我”之间的关系，能够阐明对意识难题的困惑超越了它与物质的关系这一层面，进而指出哲学和神经科学可以相互学习的途径。
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| 2. |
- Shi, Fangzhong, et al.
(författare)
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Seasonal compensation implied no weakening of the land carbon sink in the Northern Hemisphere under the 2015/2016 El Niño
- 2024
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Ingår i: Science China Earth Sciences. - 1674-7313 .- 1869-1897. ; 67:1, s. 294-308
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Tidskriftsartikel (refereegranskat)abstract
- The recurrent extreme El Niño events are commonly linked to reduced vegetation growth and the land carbon sink over many but discrete regions of the Northern Hemisphere (NH). However, we reported here a pervasive and continuous vegetation greening and no weakened land carbon sink in the maturation phase of the 2015/2016 El Niño event over the NH (mainly in the extra-tropics), based on multiple evidences from remote sensing observations, global ecosystem model simulations and atmospheric CO2 inversions. We discovered a significant compensation effect of the enhanced vegetation growth in spring on subsequent summer/autumn vegetation growth that sustained vegetation greening and led to a slight increase in the land carbon sink over the spring and summer of 2015 (average increases of 23.34% and 0.63% in net ecosystem exchange from two independent datasets relative to a 5-years average before the El Niño event, respectively) and spring of 2016 (6.82%), especially in the extra-tropics of the NH, where the water supply during the pre-growing-season (November of the previous year to March of the current year) had a positive anomaly. This seasonal compensation effect was much stronger than that in 1997 and 1998 and significantly alleviated the adverse impacts of the 2015/2016 El Niño event on vegetation growth during its maturation phase. The legacy effect of water supply during the pre-growing-season on subsequent vegetation growth lasted up to approximately six months. Our findings highlight the role of seasonal compensation effects on mediating the land carbon sink in response to episodic extreme El Niño events.
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| 3. |
- Wan, Cheng-Liang, et al.
(författare)
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基于玻璃毛细管的大气环境MeV质子微束的产生与测量 : [Production and measurement of MeV proton microbeams in atmospheric environment based on glass capillary]
- 2024
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Ingår i: Wuli xuebao. - 1000-3290. ; 73:10
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Tidskriftsartikel (refereegranskat)abstract
- 本文采用玻璃毛细管产生了大气环境中工作的2.5 MeV质子外束微束, 并对束斑直径及能量分布随玻璃毛细管与束流方向之间角度(倾角)变化进行测量. 测量结果表明, 在玻璃毛细管轴向与束流方向一致时(倾角为0°), 产生的微束中存在保持初始入射能量的直接穿透部分以及散射部分, 其中直接穿透的质子占比最大, 束斑直径也最大. 随着玻璃毛细管倾角的增大, 当其大于几何张角时, 束斑直径变小, 产生的微束全部为能量减小的散射部分, 直接穿透质子消失. 我们对质子在玻璃毛细管内传输时的内壁散射过程进行了模拟计算及离子轨迹分析, 发现大角度的散射部分决定了形成的外束微束斑外围轮廓, 而束斑中心区域由不与毛细管内壁产生任何作用的直接穿透离子构成, 其大小由玻璃毛细管出口直径以及几何容许张角决定. 采用玻璃毛细管产生的外束微束具有产生简单廉价, 微束区域定位简单的特点, 有望在辐射生物学、医学、材料等领域得到广泛应用.
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| 4. |
- Wang, Yan, et al.
(författare)
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Disaster effects of climate change and the associated scientific challenges
- 2024
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Ingår i: Chinese Science Bulletin. - 1001-6538. ; 69:2, s. 286-300
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Forskningsöversikt (refereegranskat)abstract
- Climate change can be observed in various spheres of the Earth's system, including atmosphere, lithosphere, hydrosphere, biosphere and cryosphere. The interactions among these spheres collectively impact the changes of the climate system. Natural disasters represent the most intense manifestation of the interactions among the Earth's spheres, and they have profound impacts on human society. In this study, we discuss the impact of climate change on natural disasters by examining the characteristics of climate change-induced hazards and the activity patterns of natural disasters. Furthermore, the response mechanisms of natural disasters to climate change are elaborated by exploring the formation and evolution of different types of natural disasters. Additionally, the future trends of disaster-pregnant environment under climate change are estimated, and the future trends of disaster risk are revealed by jointly considering the exposure and vulnerability. The main driving forces and formation conditions of natural disasters vary greatly among different geomorphic units, but they can generally be classified into three categories: Thermally driven disasters, gravitationally driven disasters, and hydrologically driven disasters. For example, heatwaves, tropical cyclones, tornadoes, and wildfires are common examples of thermally driven disasters which are forced by high temperatures or great thermal gradients. In addition, gravitationally driven disasters mainly occur in mountainous areas with significant differences in elevation, such as landslides, snow-ice avalanches and debris flows. The tsunamis caused by seabed movement are also gravity disasters. Furthermore, the disasters such as droughts, regional floods and sea-level rise are primarily driven by the changes in hydraulic conditions, and thus are classified as hydrologically driven disasters. In the context of enhanced climate change, the interactions among multiple spheres of the Earth's system are strengthened, causing the disaster-pregnant environment to evolve towards a more vulnerable state. Thus, the natural disasters present some new characteristics and trends, and the disaster risk shows a sharp increase. The interactions among different types of natural disasters have also become stronger, resulting in a significant rise in the risk of compound and cascading disaster. The differences in driving forces lead to significant variations in the disaster feedback to climate change among the varied geomorphic units. For example, the strengthened interaction between ocean and atmosphere leads to enhanced compound risk and destructive power of marine disasters. Besides, the intensification of water cycle contributes to increased spatial heterogeneity in drought and flood disasters, whose durations, intensities, and magnitudes show significant increasing trends. In addition, the high mountainous areas with altitude-dependent warming and the urban areas with significant heat island effects have obvious amplification effects in the responses to climate warming. This study advocates the goal of improving the accuracy and effectiveness of natural disaster prediction and early warning, and reducing the risk of climate change-related disasters. Five major scientific challenges of climate change-related disaster risk are proposed: (1) The mechanisms of climate change-driven interactions among Earth's spheres and the coupling of internal and external forces; (2) the spatio-temporal patterns of disaster development across different scales; (3) the perception of extreme event information and the data-driven risk identification; (4) the dynamics of disasters and the evolution of risk; (5) the disaster risk management and the resilient social development. By addressing the key issues in these five challenges through comprehensive and diversified approaches, we can deepen our scientific understanding on the Earth's system, adapt to global changes, and reduce disaster risks.
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| 5. |
- Zhang, Di, et al.
(författare)
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Modeling of ship navigation risk field for the icebreaker escort operations based on an artificial potential field
- 2024
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Ingår i: Harbin Gongcheng Daxue Xuebao/Journal of Harbin Engineering University. - 1006-7043. ; 45:1, s. 119-128
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Tidskriftsartikel (refereegranskat)abstract
- To assess the risk of a ship colliding and getting stuck in ice accidents, this study aims to analyze and quantify the ship navigation risk for icebreaker escort operations concerning the mutual relationship between the icebreaker and the assisted ship following the icebreaker and that between the assisted ship and sea ice. We propose a concept and model of a ship navigation risk field under an icebreaker escort operation based on an artificial potential field, including the icebreaker and sea ice risk fields. The icebreaker risk field quantifies the collision risk level between the icebreaker and the assisted ship, while the sea ice risk field quantifies the level of collision risk between the assisted ship and sea ice. The model can calculate the safe following distance between the icebreaker and the assisted ship. Finally, based on the marshaling navigation data of the TianYou ship in the Arctic, 2018, a ship navigation risk field model for an icebreaker escort operation is constructed for simulation verification. Results show that the proposed model is feasible and practical, which can theoretically support safety research following the distance between the icebreaker and the assisted ship under the icebreaker escort operation.
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| 9. |
- Li, Kai, et al.
(författare)
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Metal thermopile infrared detector with vertical graphene
- 2023
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Ingår i: Wuli Xuebao/Acta Physica Sinica. - : Acta Physica Sinica, Chinese Physical Society and Institute of Physics, Chinese Academy of Sciences. - 1000-3290. ; 72:3
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Tidskriftsartikel (refereegranskat)abstract
- Thermopile infrared detector is a kind of detector device mainly composed of thermocouple as the basic unit. Because of its simple principle, no need of cooling equipment, and other advantages, it has been widely used in various fields of production and life. However, the absorption rates of the materials in conventional thermopile devices are poor, and the majority of them are incompatible with microfabrication methods. In this work, a metal thermopile infrared detector with vertical graphene (VG) is designed and fabricated. The VG is grown via plasma enhanced chemical vapor deposition, and retained at the device’s thermal ends to provide the thermopile IR detector’s wideband and high response characteristics. The detector achieves a room temperature responsivity reaching a value as high as 1.53 V/W at 792 nm, which can increase the response results about 28 times and reduce the response time to 0.8 ms compared with the thermopile detector without VG. After systematically measuring the response results, it is finally found that there are three main mechanisms responsible for the response on the composite device. The first one is the response generated by the metal thermopile itself alone. The second one is the response increased eventually by the contribution of VG covered at the metal thermal junction that expands the temperature difference. The last one is the response generated by the temperature gradient existing inside the VG on the surface of the device after the absorption of heat. The portion of each partial response mechanism in the total response is also analyzed, providing a new reference direction for analyzing the response generation mechanism of thermopile detectors with other absorbing materials. The process is compatible with the microfabrication, while the device performance is enhanced and suitable for mass production. Furthermore, by utilizing the surface plasmon resonance to combine VG with metal nanoparticles, the material’ s light absorption is found to be enhanced significantly under the same conditions, and the resulting thermal voltage can be increased to 6 times. The results indicate that VG promises to possess practical applications, in many fields such as photoelectric sensing and power production devices. This technology provides a new method to manufacture high-performance thermopile infrared detectors and other sensor devices.
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