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1.
Innovation (Camb) ; 5(5): 100663, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39071219

RESUMO

Research on returned samples can provide ground truth for the study of the geological evolution history of the Moon. However, previous missions all collected samples from the near side of the Moon, which is significantly different from the far side of the Moon in terms of the thickness of the lunar crust, magma activity, and composition. Therefore, the samples from the far side of the Moon are of great significance for a comprehensive understanding of the history of the Moon. China's Chang'e-6 (CE-6) probe has successfully landed on the lunar far side and will return samples in the coming days. With the precise location of the CE-6 landing site, a detailed analysis of the geological background is conducted in this research. The landing site of CE-6 is within the Apollo crater, which is inside the largest impact basin on the Moon, i.e., the South Pole-Aitken (SPA) basin. According to the numerical simulation of the formation process of the SPA basin, CE-6 landed at the edge of the SPA impact melting zone, which is presumably composed of impact melt of the lunar mantle. The Apollo crater subsequently excavated deep material again, which constitutes the basement of the CE-6 landing area. Later, erupted basalt covered these basement rocks, and they also constitute the main source of the CE-6 samples. Based on the dating method of crater size-frequency distribution, we find that the basalt is ∼2.50 Ga. The CE-6 samples also possibly contain basement rocks as excavated and ejected by craters, and they can provide crucial information for our understanding of lunar geological history along with the basalt samples.

2.
Sci Bull (Beijing) ; 69(13): 2136-2148, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38777682

RESUMO

Lunar exploration is deemed crucial for uncovering the origins of the Earth-Moon system and is the first step for advancing humanity's exploration of deep space. Over the past decade, the Chinese Lunar Exploration Program (CLEP), also known as the Chang'e (CE) Project, has achieved remarkable milestones. It has successfully developed and demonstrated the engineering capability required to reach and return from the lunar surface. Notably, the CE Project has made historic firsts with the landing and on-site exploration of the far side of the Moon, along with the collection of the youngest volcanic samples from the Procellarum KREEP Terrane. These achievements have significantly enhanced our understanding of lunar evolution. Building on this success, China has proposed an ambitious crewed lunar exploration strategy, aiming to return to the Moon for scientific exploration and utilization. This plan encompasses two primary phases: the first crewed lunar landing and exploration, followed by a thousand-kilometer scale scientific expedition to construct a geological cross-section across the lunar surface. Recognizing the limitations of current lunar exploration efforts and China's engineering and technical capabilities, this paper explores the benefits of crewed lunar exploration while leveraging synergies with robotic exploration. The study refines fundamental lunar scientific questions that could lead to significant breakthroughs, considering the respective engineering and technological requirements. This research lays a crucial foundation for defining the objectives of future lunar exploration, emphasizing the importance of crewed missions and offering insights into potential advancements in lunar science.

3.
Zhen Ci Yan Jiu ; 46(6): 474-9, 2021 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-34190450

RESUMO

In learning and evaluation of acupuncture manipulations, there are lack of quantitative physical parameters on exertion strength, duration and direction of acupuncture technique at present. Based on the tactile parameters collected during "twirling" and "lifting-thrusting" of needling, a kind of array polyvinylidene fluoride (PVDF) tactile sensor was designed. Followed by, a window segmentation method for tactile signal was proposed and the time domain features of the window were extracted. Finally, an identification method of acupuncture manipulation based on FCM (Fuzzy C-Means) was constructed. Through the experiment, it was proved that this sensor can effectively identify the four kinds of basic acupuncture manipulations, i.e. reinforcing by twirling and rotating, reducing by twirling and rotating, reinforcing by lifting and thrusting and reducing by lifting and thrusting and it was conductive to the quantification and dissemination of acupuncture manipulations.


Assuntos
Pontos de Acupuntura , Terapia por Acupuntura , Artérias , Aprendizado de Máquina , Polivinil
4.
Natl Sci Rev ; 7(5): 913-920, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-34692112

RESUMO

Chang'E-4 landed in the South Pole-Aitken (SPA) basin, providing a unique chance to probe the composition of the lunar interior. Its landing site is located on ejecta strips in Von Kármán crater that possibly originate from the neighboring Finsen crater. A surface rock and the lunar regolith at 10 sites along the rover Yutu-2 track were measured by the onboard Visible and Near-Infrared Imaging Spectrometer in the first three lunar days of mission operations. In situ spectra of the regolith have peak band positions at 1 and 2 µm, similar to the spectral data of Finsen ejecta from the Moon Mineralogy Mapper, which confirms that the regolith's composition of the landing area is mostly similar to that of Finsen ejecta. The rock spectrum shows similar band peak positions, but stronger absorptions, suggesting relatively fresh exposure. The rock may consist of 38.1 ± 5.4% low-Ca pyroxene, 13.9 ± 5.1% olivine and 48.0 ± 3.1% plagioclase, referred to as olivine-norite. The plagioclase-abundant and olivine-poor modal composition of the rock is inconsistent with the origin of the mantle, but representative of the lunar lower crust. Alternatively, the rock crystallized from the impact-derived melt pool formed by the SPA-impact event via mixing the lunar crust and mantle materials. This scenario is consistent with fast-cooling thermal conditions of a shallow melt pool, indicated by the fine to medium-sized texture (<3 mm) of the rock and the SPA-impact melting model [Icarus 2012; 220: 730-43].

5.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 1): o151, 2007 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-21200716

RESUMO

The title mol-ecule, C(13)H(11)NO, is almost flat, the angle between the pyrrole and the phenyl rings being 10.9 (1)°. The atoms of the central C(3)O unit are coplanar, with a mean deviation from the plane of 0.001 (1) Å. The angles between this plane and the pyrrole and phenyl rings are 3.3 (1) and 8.0 (1)°, respectively. The mol-ecules form centrosymmetric dimers through a pair of N-H⋯O hydrogen bonds with an R(2) (2)(10) motif.

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