Advances in Space Research最新文献

{"title":"Economical extraction of platinum from main belt asteroids","authors":"Peter J. Schubert","doi":"10.1016/j.asr.2025.02.035","DOIUrl":"10.1016/j.asr.2025.02.035","url":null,"abstract":"<div><div>Metallic M−class asteroids may contain 20 to 100 parts per million (ppm) of platinum-group metals (PGM), dissolved within a nickel–iron matrix. Economic extraction of these resources has been elusive. This work introduces two new architectures to produce 43 metric tons (MT) of PGM from a Main Belt asteroid within a 12-month mission duration. A cornerstone of this capability is the transmutation of lunar thorium to the isotope uranium-233. Fission reactors loaded with lunar-sourced fuel pins are used for rapid transport as well as for electric power to refine the metals. A key safety bonus with fission fuel produced on the Moon is that no radioactive materials need to be launched through Earth’s atmosphere. Neutrons are required for transmuting thorium, so a non-radioactive compact accelerator neutron source (CANS) is designed for this purpose, as well as for heating and refining of the asteroidal ore. The concept of operations begins with a precursor mission of five-months duration to the lunar surface, followed by soft landing of an ascent rocket to loft the U-233 to Low Lunar Orbit (LLO). A rendezvous in LLO with Earth-launched hardware, including a (not yet radioactive) nuclear thermal rocket (NTR), is followed by a three-month transit to a 250 m diameter asteroid orbiting Sol at 2.5 to 3.5 AU. A unique feature of this class of architecture is a circumferential track around which a processing bogie orbits. Crucibles containing molten metal face inward, towards the asteroid. As the transition metals are boiled off at 1728 K, they impinge on the regolith surface. As a result, the asteroid becomes (partly) encased in a thick layer of steel. When evaporation is complete at this temperature, a nugget of PGM remains held within the crucible, ready for extraction. Techno-economic analysis shows that one of these architectures can achieve economic self-sufficiency upon completion of the first one-year mission. The other architecture requires two missions to reach cost breakeven, but is more easily re-used. Both approaches build an enduring lunar infrastructure that can support many such missions, plus a wide range of habitation needs and additional in situ resource utilization (ISRU) applications.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 8","pages":"Pages 6132-6139"},"PeriodicalIF":2.8,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143791817","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A deep learning-enhanced observation-domain multipath mitigation study of BDS-3","authors":"Chao Liu ,&nbsp;Runfa Tong ,&nbsp;Yuan Tao ,&nbsp;Jian Chen ,&nbsp;Jian Wang","doi":"10.1016/j.asr.2025.02.038","DOIUrl":"10.1016/j.asr.2025.02.038","url":null,"abstract":"<div><div>Multipath is the main error source limiting high-precision Global Navigation Satellite System (GNSS) positioning. Multipath repeat periods of the three kinds of orbital satellites are inconsistent based on the study of the BeiDou navigation satellite system orbital repeat period. The use of advanced sidereal filtering (ASF) requires accurate calculation of the repeat periods for each satellite, which increases the complexity of the ASF model and is insensitive to satellite orbital maneuvers. Therefore, we propose a deep learning-enhanced (DL) observation-domain multipath mitigation method, in which the single difference residuals are trained to obtain multipath models that tend to be optimal using a convolutional neural network and long short-term memory. We obtained the predicted multipath by inputting previous single difference residuals into the multipath model in the process of real-time multipath mitigation. Experiments show that the proposed method can extract multipath information for more range frequencies (0.006–0.040 Hz) than the ASF and multipath hemispherical map (MHM) methods, and avoids the process of calculating repeat periods. In the single difference residuals, the DL method improved by 8.11 % and 9.27 % over the ASF and MHM methods; in the coordinates, the accuracy improvement of the DL method increased by 8–12 % in the E, N, and U directions compared with the ASF and MHM methods. The positioning accuracy and robustness of the DL method were better than those of the ASF and MHM methods. The proposed method provides technological support for real-time, high-precision deformation monitoring and seismic research.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 10","pages":"Pages 7049-7064"},"PeriodicalIF":2.8,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143907534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"GNSS-IR water level monitoring for complex environments: Application to Kalabeily Reservoir in Xinjiang, China","authors":"Peiyuan Wang ,&nbsp;Rui Tu ,&nbsp;Xiaolei Wang ,&nbsp;Junqiang Han ,&nbsp;Junjian Zhang ,&nbsp;Fang Cheng ,&nbsp;Xiaochun Lu","doi":"10.1016/j.asr.2025.02.036","DOIUrl":"10.1016/j.asr.2025.02.036","url":null,"abstract":"<div><div>Water level monitoring plays a crucial role in managing water resources, flood prevention, and disaster mitigation in reservoirs. The technology of Global Navigation Satellite System-Interferometric Reflectometry (GNSS-IR) has been extensively utilized for water level monitoring in various types of water bodies. However, owing to significant annual water level fluctuations and narrow reflection zones in some reservoirs, this poses a major challenge for the usage of GNSS-IR in reservoir monitoring. To address these challenges, this study proposes a method for dynamically selecting the elevation angle range (DSEAR). In this study, observation data from a GNSS monitoring network established around the Kalabeily Reservoir, comprising one reference station and five monitoring stations, is utilized for water level retrieval. It has been demonstrated that this method effectively expands the usable elevation angle range and increases the reflection zones, thereby improving the success rate and reliability of the retrieval results. This method also lays the foundation for real-time monitoring of reservoir water levels. To additionally, improve the retrieval accuracy, an algorithm for water level retrieval combining multi-station multi-signal data is proposed, based on a robust estimation strategy. The results indicate that the multi-station multi-signal combination retrieval method can achieve a maximum accuracy improvement of 44.70% compared to the single-station multi-signal retrieval method. The water level retrieval sequences from 2023 also exhibit consistency with the reservoir operation mode. This confirms the significant potential of GNSS-IR technology in complex environments.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 10","pages":"Pages 7035-7048"},"PeriodicalIF":2.8,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143906050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An HF channel parameter estimation method based on HR-IPFrFT","authors":"Qiang Guo ,&nbsp;Bo Na ,&nbsp;Stepan Douplii","doi":"10.1016/j.asr.2025.02.037","DOIUrl":"10.1016/j.asr.2025.02.037","url":null,"abstract":"<div><div>The long-distance high-frequency (HF) ionospheric channel is characterized by high noise levels and severe signal fading, which seriously affects signal capture and channel parameter extraction. Chirp continuous wave is often applied as a transmitted waveform due to its anti-noise and anti-Doppler advantages. The periodic fractional Fourier transform (PFrFT) algorithm possesses the optimal detection capability for chirp continuous waves. It can achieve periodic energy accumulation at the specific order. This paper proposes a new HF channel parameter estimation method combining their advantages. Firstly, an high-resolution improved periodic fractional Fourier transform (HR-IPFrFT) algorithm is introduced. This algorithm adapts the kernel function to fit the periodic chirp signal and then gives the periodic non-coherent accumulation expression for the discrete HR-IPFrFT. In this expression, two adjustable factors introduced can flexibly adjust the fractional domain range. Further, it is demonstrated that the HR-IPFrFT shows time-shifted and frequency-shifted properties. The parameter estimation method uses a dual-chirp continuous wave as the transmitted signal. By analyzing the variation of the peak position of the received signal in the HR-IPFrFT domain, the channel parameters are accurately extracted. Simulation and experiments show that this method exhibits superior parameter identification and estimation accuracy under low signal-to-noise ratio and severe fading conditions</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 10","pages":"Pages 7624-7644"},"PeriodicalIF":2.8,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143906862","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flow modelling of a rocket nozzle using hydrogen and methane propellants","authors":"Naveen Kumar,&nbsp;Sudheer Siddapureddy","doi":"10.1016/j.asr.2025.02.039","DOIUrl":"10.1016/j.asr.2025.02.039","url":null,"abstract":"<div><div>This research is of paramount importance to space agencies due to its critical role in advancing efficient propulsion systems for rocket engines. Specifically, it focuses on the flow modeling of high-area ratio (HAR) rocket nozzles, which are essential for achieving high-speed propulsion. The study explores the complex interactions between turbulence and chemical reactions, with particular emphasis on the dominance of radiative heating in hypersonic flows. It numerically investigates the flow dynamics of rocket nozzles using hydrogen and methane as propellants, analyzing the effects of nozzle pressure ratio (NPR) and temperature to identify optimal operating conditions for maximum exit velocity. Simulations are performed with a modified hypersonic flow solver, employing the ROE scheme and a second-order Runge-Kutta method within the OpenFOAM framework. The turbulence-chemistry interactions (TCI) are captured using an eddy-dissipation concept (EDC), and full-spectrum <em>k</em>-distribution (FSK) correlations for CO₂ and H₂O are implemented to model non-gray radiative heat transfer accurately. Validation against experimental and numerical data confirms the accuracy of the results. The comparison at different NPRs and temperatures reveals that a nozzle with an NPR of 9261.74 and an inlet temperature of 3040.71 K provides the best performance. The study finds a significant increase in exit Mach number (37 %) and specific impulse (32.40 %) when using hydrogen as the propellant compared to methane. Additionally, the results show that TCI strongly influences flow fields, and radiative heat flux dominates convective flux in hypersonic rocket nozzle flows. Overall, this research provides valuable insights into the multi-physics phenomena governing rocket propulsion systems.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 10","pages":"Pages 7445-7465"},"PeriodicalIF":2.8,"publicationDate":"2025-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143906944","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"LK-UNet: Large Kernel convolution-driven U-shaped network for semantic segmentation of high-resolution Earth surface images","authors":"Bin Liu,&nbsp;Bing Li,&nbsp;Shuofeng Li","doi":"10.1016/j.asr.2025.02.033","DOIUrl":"10.1016/j.asr.2025.02.033","url":null,"abstract":"<div><div>Semantic segmentation of remote sensing (RS) images plays an important role in urban planning, environmental monitoring, and agriculture. However, the receptive field of traditional convolutional neural networks (CNNs) is limited, and the model cannot capture the wider context information in the image, resulting in poor segmentation results. Therefore, this paper re-examines the role of large convolution kernels and proposes a new network LK-UNet. First, a U-shaped network driven by a large convolution kernel as the encoder is proposed to increase the receptive field and greatly improve the network’s ability to extract global information. Secondly, the enhanced atrous spatial pyramid pooling (EASPP) module is introduced in the last two stages of the encoder module to aggregate broader contextual information. Finally, in the skip connection part, the feature enhancement module (FEM) is incorporated to augment the network’s ability to capture details and further improve the target segmentation performance. Ablation experiments were performed on the ISPRS Vaihingen to validate the efficacy of each module. At the same time, the proposed method has superior performance compared with the state-of-the-art methods.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 10","pages":"Pages 7020-7034"},"PeriodicalIF":2.8,"publicationDate":"2025-02-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143906048","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An experimental study of performance and thrust control characteristics of N2O-based rotating gliding arc thrusters","authors":"Jeongrak Lee ,&nbsp;Seonghyeon Kim ,&nbsp;Anna Lee ,&nbsp;Hongjae Kang","doi":"10.1016/j.asr.2025.02.032","DOIUrl":"10.1016/j.asr.2025.02.032","url":null,"abstract":"<div><div>The recent growth of the launch vehicle market has made orbit access more affordable and expanded the range of mission types and orbits, requiring customized propulsion systems with high flexibility. In this study, a novel electro-chemical thruster with an N₂O monopropellant and AC-powered rotating gliding arc (RGA) was proposed. Furthermore, the thruster propulsion performance and thrust control characteristics as a function of the N₂O flow rate and applied power were systematically analyzed. The RGA thruster rotated the arc by using the swirl flow and repeated AC arc discharge. The thruster can maintain a stable discharge at maximum chamber pressures of up to approximately seven times the atmospheric pressure. Additionally, the thruster could achieve instantaneous N₂O decomposition without the use of a catalyst, and the remaining electrical power after decomposition could be used to heat products, resulting in enhanced performance. Under all experimental conditions, the characteristic velocity efficiency exceeded 100 %, with a maximum efficiency of 136.5 %. Additionally, the concept of effective temperature was introduced to simplify performance predictions for the RGA thruster. The effective gas temperature under these conditions was estimated to be 3410 K, and the vacuum-specific impulse was calculated to be 278.9 s, which was higher than the specific impulse of 202.8 s for chemically decomposed N₂O. Thrust control experiments confirmed that the N₂O flow rate and applied power could be independently controlled, enabling precise target thrust generation. This result revealed that both continuous and discrete thrust control based on impulse bits are viable and satisfy the high maneuverability and flexibility demands of space missions.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 8","pages":"Pages 6118-6131"},"PeriodicalIF":2.8,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143791901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An efficient and global method for orbit uncertainty propagation near irregular-shaped asteroids","authors":"Xuefen Zhang,&nbsp;Haibin Shang,&nbsp;Jucheng Lu,&nbsp;Zichen Zhao","doi":"10.1016/j.asr.2025.02.031","DOIUrl":"10.1016/j.asr.2025.02.031","url":null,"abstract":"<div><div>Asteroid close-proximity missions, such as orbiting, hovering, and landing, face significant dynamical challenges owing to the irregular and highly perturbed gravitational field. Orbital uncertainty plays a key role in close-proximity operations around asteroids. This study seeks to develop an efficient and global approach for dealing with orbit uncertainty propagation in an asteroid dynamical environment. First, to achieve global applicability and enhance efficiency, the quadrature-based polyhedral model is employed to represent the gravity of the irregularly shaped asteroid. The solar radiation pressure and the Sun’s third-body gravity are considered to ensure the accuracy of the dynamic model. Second, the Analytic Continuation technique, originally developed for the perturbed two-body problem, is expanded to compute higher-order State Transition Tensors (STTs) of the high-fidelity dynamics. Recursive formulas for the time derivatives of STTs are obtained using the Leibniz product rule, enabling the STTs to be conveniently approximated through arbitrary-order Taylor series. Finally, by incorporating adaptive time steps and expansion order, an efficient algorithm for predicting the orbit state probability density function is developed. The orbit near the irregularly shaped, dog-bone-like asteroid 216 Kleopatra is used to demonstrate the effectiveness of the proposed method. Numerical simulations confirm the global applicability of the proposed method for uncertainty propagation, even for orbits involving multiple close flybys over the asteroid. Using only the fourth-order STT achieves results similar to full-scale Monte Carlo simulations with 50,000 samples but only needs 3% of the computational effort. These results strongly demonstrate that the proposed algorithm is a suitable tool for uncertainty propagation in asteroid exploration mission analysis.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 8","pages":"Pages 6406-6424"},"PeriodicalIF":2.8,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143791670","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geological environment carrying capacity assessment using remote sensing and integrated modeling: A case study of Yi’an district, Tongling, China","authors":"Dazhi Ni ,&nbsp;Chuangang Gong ,&nbsp;Dan Ding ,&nbsp;Yu Tian","doi":"10.1016/j.asr.2025.02.034","DOIUrl":"10.1016/j.asr.2025.02.034","url":null,"abstract":"<div><div>The central tenet of Regional Sustainable Development (RSD) is fundamentally reliant on the Geological Environment Carrying Capacity (GECC). An in-depth comprehension of a region’s current geological environmental status is crucial for formulating pragmatic and efficacious management strategies. This is essential for laying a robust groundwork for scientifically informed regional development planning. In this context, our research zeroes in on the Yi’an District of Tongling, utilizing a suite of nine evaluative metrics that span geological, ecological, and socio-economic dimensions. We adopt a methodological approach involving the Information Value (<em>I</em>), Random Forest (RF), and Extreme Gradient Boosting (XGBoost or XGB) algorithms to construct a comprehensive GECC assessment framework to improve the precision of GECC predictions. This framework is further augmented through the application of the Receiver Operating Characteristic (ROC) curve for nuanced model comparison and analytical purposes. Our findings indicate that factors such as slope, topographic relief, and the Normalized Difference Vegetation Index (NDVI) have a marked impact on GECC. The I-RF model demonstrates superior predictive precision over the I-XGB model, thus providing a more accurate evaluation of GECC. The overall GECC in the Yi’an District is assessed as favorable. However, areas with suboptimal GECC, predominantly located in the southern, southeastern, and western hilly terrains, are largely attributed to mining activities and urban developmental pressures. These insights are instrumental for local administrative bodies to enact proactive and efficacious mitigation strategies. This study significantly contributes to the scientific underpinning of geological environmental safety and bolsters the sustainable economic advancement of the region.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 8","pages":"Pages 6274-6286"},"PeriodicalIF":2.8,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143791736","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A comprehensive survey of the GEO-belt using simultaneous four-colour observations with STING","authors":"Robert J.S. Airey ,&nbsp;Paul Chote ,&nbsp;James A. Blake ,&nbsp;Benjamin F. Cooke ,&nbsp;James McCormac ,&nbsp;Phineas Allen ,&nbsp;Alex MacManus ,&nbsp;Don Pollacco ,&nbsp;Billy Shrive ,&nbsp;Richard West","doi":"10.1016/j.asr.2025.02.027","DOIUrl":"10.1016/j.asr.2025.02.027","url":null,"abstract":"<div><div>Colour light curves of resident space objects (RSOs) encapsulate distinctive features that can offer insights into an object’s structure and design, making them an invaluable tool for classification and characterisation. We present the results of the first large systematic colour survey of the GEO (Geostationary Earth Orbit) belt in which we obtain full-night multi-colour light curves for 112 active geostationary objects between April and May 2023. This survey was undertaken during the ‘glint’ season using the STING telescope located at the Roque de Los Muchachos observatory in the Canary Islands.</div><div>Colour light curve maps were created to compare and contrast the colours between different satellites and bus configurations. We find that satellites with BSS-702 and STAR-2 buses can be effectively distinguished from the colour measurements on these maps, but comparing the average colour of individual satellites within given solar equatorial phase angle ranges shows that it is difficult to distinguish between bus configurations based on colour alone. We also find tentative evidence to suggest that there is a relationship between colour and time spent on orbit for the Eurostar-3000 class satellites, which is unseen behaviour within other bus configuration classes. The satellites in our sample exhibit ‘redder’ colours than the Sun, which is in agreement with previous findings.</div><div>We found common light curve features such as symmetrical colour changes as well as unique regions of short timescale glinting which are ‘bluer’ than other regimes within the colour light curves. If these features are indeed seasonal, this would be a powerful characterisation tool. We are able to detect and resolve features in the light curve of the LDPE-3A satellite related to manoeuvres being performed.</div><div>Finally, we measured the solar panel offsets of 54 satellites in our sample and found variation in the type of colour response. The majority of which did not exhibit any colour change across the solar panel glints compared to them shifting towards ’redder’ or ’bluer’ colours.</div></div>","PeriodicalId":50850,"journal":{"name":"Advances in Space Research","volume":"75 7","pages":"Pages 5757-5780"},"PeriodicalIF":2.8,"publicationDate":"2025-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143683733","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}