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Petroleum Science 2024年第4期21卷 2383-2392页

作者： li-Ming Zhao Cai-ping Lu Yang liu Chao-Chao li School of Mines China University of Mining and Technology Henan Institute of Geophysical Space Information

The similarities and differences in inherent mechanism and characteristic frequency between the onedimensional(1D) poroelastic model and the layered White model were investigated. This investigation was conducted under the assumption that the rock was homogenous and isotropic at the mesoscopic scale. For the inherent mechanism, both models resulted from quasi-static flow in a slow P-wave diffusion mode, and the differences between them originated from saturated fluids and boundary conditions. On the other hand, for the characteristic frequencies of the models, the characteristic frequency of the 1D poroelastic model was first modified because the elastic constant and formula for calculating it were misused and then compared to that of the layered White model. Both of them moved towards higher frequencies with increasing permeability and decreasing viscosity and diffusion length. The differences between them were due to the diffusion length. The diffusion length for the 1D poroelastic model was determined by the sample length, whereas that for the layered White model was determined by the length of the representative elementary volume(REV). Subsequently, a numerical example was presented to demonstrate the similarities and differences between the models. Finally, published experimental data were interpreted using the 1D poroelastic model combined with the Cole-Cole *** prediction of the combined model was in good agreement with the experimental data, thereby validating the effectiveness of the 1D poroelastic model. Furthermore, the modified characteristic frequency in our study was much closer to the experimental data than the previous prediction, validating the effectiveness of our modification of the characteristic frequency of the 1D poroelastic model. The investigation provided insight into the internal relationship between wave-induced fluid flow(WIFF)models at macroscopic and mesoscopic scales and can aid in a better understanding of the elastic modulus d

关键词： 1D poroelastic model Layered White model Quasi-static flow Slow P-wave diffusion Characteristic frequency Diffusion length

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Dynamic simulation analysis of molten salt reactor-coupled air-steam combined cycle power generation system

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Nuclear Science and Techniques 2024年第2期35卷 222-233页

作者： Jing-Lei Huang Guo-Bin Jia li-Feng han Wen-Qian liu li Huang Zheng-han Yang Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

A nonlinear dynamic simulation model based on coordinated control of speed and flow rate for the molten salt reactor and combined cycle systems is proposed here to ensure the coordination and stability between the molten salt reactor and power *** model considers the impact of thermal properties of fluid variation on accuracy and has been validated with *** study reveals the capability of the control system to compensate for anomalous situations and maintain shaft stability in the event of perturbations occurring in high-temperature molten salt tank outlet ***,the control system’s impact on the system’s dynamic characteristics under molten salt disturbance is also *** results reveal that after the disturbance occurs,the controlled system benefits from the action of the control,and the overshoot and disturbance amplitude are positively correlated,while the system power and frequency eventually return to the initial *** simulation model provides a basis for utilizing molten salt reactors for power generation and maintaining grid stability.

关键词： Molten salt reactor Combined cycle Dynamic characteristic Control

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Slip distribution inversion of seismic sub-fault dip iteration using gradient based optimizer algorithm

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Geodesy and Geodynamics 2024年第2期15卷 114-121页

作者： Leyang Wang han li Ming Pang Key Laboratory of Mine Environmental Monitoring and Improving Around Poyang Lake of Ministry of Natural Resources East China University of TechnologyNanchang 330013China School of Surveying and Geoinformation Engineering East China University of TechnologyNanchang 330013China College of Resources and Environment Shandong Agricultural UniversityTaian 271018China

This paper considers setting different dips for different sub-faults to fit the actual rupture situation based on the fault rupture of the 2013 Lushan M_(S)7.0 ***,combined with the coseismic GNSS data of the Lushan earthquake,the source parameters and sliding distribution of the Lushan earthquake fault are ***,we use the gradient based optimizer(GBO)in nonlinear inversion to obtain the source parameters of this seismic *** inversion results indicate that the strike of the fault is 206.52°,the dip is 44.10°,the length is 21.92 km,and the depth is 12.79 *** refine the sliding distribution of the seismic fault,the seismic fault is divided into 3×3 ***,we fix the central sub-fault dip of 44.10°;the dip of other sub-faults is obtained by *** that,the model is further divided into a fault layer model composed of 23×19 sub fault slices,and using the Matlab fitting function is used to fit the dip of the 23×19 sub ***,the Lushan seismic fault plane is established as a shovel structure with steep upper and gentle lower,steep south and gentle *** slip distribution inversion results indicate that the depth of the slip peak is 13 km,the corresponding maximum slip momentum is 0.67 m,the seismic moment is 1.10×10^(19)N·m and the corresponding moment magnitude is *** results above are consistent with the research results of seismology.

关键词： Gradient basedoptimizer(GBO) Lushan earthquake Non-planefault model Slid distribution

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Effects of nitrogen deposition on the carbon budget and water stress in Central Asia under climate change

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Journal of Arid Land 2024年第8期16卷 1118-1129页

作者： han Qifei XU Wei li Chaofan School of Geographical Sciences Nanjing University of Information Science&TechnologyNanjing 210044China

Atmospheric deposition of nitrogen(N)plays a significant role in shaping the structure and functioning of various terrestrial ecosystems ***,the magnitude of N deposition on grassland ecosystems in Central Asia still remains highly *** this study,a multi-data approach was adopted to analyze the distribution and amplitude of N deposition effects in Central Asia from 1979 to 2014 using a process-based denitrification decomposition(DNDC)*** showed that total vegetation carbon(C)in Central Asia was 0.35(±0.09)Pg C/a and the averaged water stress index(WSI)was 0.20(±0.02)for the whole *** N deposition led to an increase in the vegetation C of 65.56(±83.03)Tg C and slightly decreased water stress in Central *** of this study will expand both our understanding and predictive capacity of C characteristics under future increases in N deposition,and also serve as a valuable reference for decision-making regarding water resources management and climate change mitigation in arid and semi-arid areas globally.

关键词： carbon dynamics climate change grassland ecosystems nitrogen deposition water stress index

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Rapid prediction of damaged ship roll motion responses in beam waves based on stacking algorithm

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Journal of Hydrodynamics 2024年第2期36卷 394-405页

作者： Xin-ran liu Ting-qiu li Zi-ping Wang School of Naval Architecture Ocean and Energy Power EngineeringWuhan University of TechnologyWuhan430063China

Accurate modeling for highly non-linear coupling of a damaged ship with liquid sloshing in waves is still of considerable interest within the computational fluid dynamics(CFD)and AI *** paper describes a data-driven Stacking algorithm for fast prediction of roll motion response amplitudes in beam waves by constructing a hydrodynamics model of a damaged ship based on the dynamic overlapping grid CFD *** general idea is to optimize various parameters varying with four types of classical base models like multi-layer perception,support vector regression,random forest,and hist gradient boosting *** offers several attractive properties in terms of accuracy and efficiency by choosing the standard DTMB 5415 model with double damaged compartments for *** is clearly demonstrated that the predicted response amplitude operator(RAO)in the regular beam waves agrees well with the experimental data available,which verifies the accuracy of the established damaged ship hydrodynamics *** high-quality CFD samples,therefore,implementation of the designed Stacking algorithm with its optimal combination can predict the damaged ship roll motion amplitudes effectively and accurately(e.g.,the coefficient of determination 0.9926,the average absolute error 0.0955 and CPU 3s),by comparison of four types of typical base models and their various ***,the established Stacking algorithm provides one potential that can break through problems involving the time-consuming and low efficiency for large-scale lengthy CFD simulations.

关键词： Ship motion damaged ship computational fluid dynamics(CFD) machine learning stacking algorithm

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Analyzing the spatiotemporal evolution and driving forces of gross ecosystem product in the upper reaches of the Chaobai River Basin

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Frontiers of Environmental Science & Engineering 2024年第8期18卷 117-132页

作者： Jiacheng li Qi han liqiu Zhang li Feng Guihuan liu Beijing Key Laboratory for Source Control Technology of Water Pollution College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China Engineering Research Center for Water Pollution Source Control&Eco-remediation College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China Center of Eco-compensation Chinese Academy of Environmental PlanningMinistry of Ecology of EnvironmentBeijing 100041China

The Chaobai River Basin,which is a crucial ecological barrier and primary water source area within the Beijing-Tianjin-Hebei region,possesses substantial ecological *** gross ecosystem product(GEP)in the Chaobai River Basin is a reflection of ecosystem conditions and quantifies nature’s contributions to humanity,which provides a basis for basin ecosystem service management and *** study investigated the spatiotemporal evolution of GEP in the upper Chaobai River Basin and explored the driving factors influencing GEP spatial *** patterns from 2005 to 2020 were analyzed,and GEP was calculated for 2005,2010,2015,and *** driving factors influencing GEP spatial differentiation were identified using the optimal parameter-based geographical detector(OPGD)*** key findings are as follows:(1)From 2005 to 2020,the main ecosystem types were forest,grassland,and *** areas experienced significant changes,and conversions mainly occurred among urban,water,grassland and agricultural ecosystems.(2)Temporally,the GEP in the basin increased from 2005 to 2020,with regulation services *** the county(district)scale,GEP exhibited a north-west-high and south-east-low pattern,showing spatial differences between per-unit-area GEP and county(district)GEP,while the spatial variations in per capita GEP and county(district)GEP were similar.(3)Differences in the spatial distribution of GEP were influenced by regional natural geographical and socioeconomic *** these factors,gross domestic product,population density,and land-use degree density contributed *** among different driving forces noticeably impacted GEP spatial *** findings underscore the necessity of incorporating factors such as population density and the intensity of land-use development into ecosystem management decision-making processes in the upper reaches of the Chaobai River *** policies

关键词： Ecosystem pattern Gross ecosystem product(GEP) Spatiotemporal evolution Optimal parameter-based geographical detector(OPGD) Chaobai River Basin

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Built-in electric field induced S-scheme g-C_(3)N_(4)homojunction for efficient photocatalytic hydrogen evolution:Interfacial engineering and morphology control

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Nano Research 2024年第6期17卷 4961-4970页

作者： Yongpan Gu Yike li Haoqiang Feng Yanan han Zhongjun li College of Chemistry Zhengzhou UniversityZhengzhou 450001China

S-scheme possesses superior redox capabilities compared with the II-scheme,providing an effective method to solve the innate defects of g-C_(3)N_(4)(CN).In this study,S-doped g-C_(3)N_(4)/g-C_(3)N_(4)(SCN-tm/CN)S-scheme homojunction was constructed by rationally integrating morphology control with interfacial engineering to enhance the photocatalytic hydrogen evolution ***-situ Kelvin probe force microscopy(KPFM)confirms the transport of photo-generated electrons from CN to *** functional theory(DFT)calculations reveal that the generation of a built-in electric field between SCN and CN enables the carrier separation to be more efficient and *** transient absorption spectrum(fs-TAS)indicates prolonged lifetimes of SCN-tm/CN_(3)(τ1:9.7,τ2:110,andτ3:1343.5 ps)in comparison to those of CN(τ1:4.86,τ2:55.2,andτ3:927 ps),signifying that the construction of homojunction promotes the separation and transport of electron hole pairs,thus favoring the photocatalytic *** visible light irradiation,the optimized SCN-tm/CN_(3)exhibits excellent photocatalytic activity with the hydrogen evolution rate of 5407.3μmol·g^(−1)·h^(−1),which is 20.4 times higher than that of CN(265.7μmol·g^(−1)·h^(−1)).Moreover,the homojunction also displays an apparent quantum efficiency of 26.8%at 435 nm as well as ultra-long and ultra-stable cycle *** work offers a new strategy to construct highly efficient photocatalysts based on the metal-free conjugated polymeric CN for realizing solar energy conversion.

关键词： homojunction built-in electric field morphology control interfacial engineering carrier separation

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Sulfate-assisted Ni/Fe-based electrodes for anion exchange membrane saline splitting

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Nano Research 2024年第7期17卷 5985-5995页

作者： Yujun han li Shao Yuhang liu Guodong li Tongzhou Wang Xuerong Zheng Jihong li Xiaopeng han Wenbin Hu Yida Deng School of Materials Science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin UniversityTianjin 300072China State Key Laboratory of Marine Resource Utilization in South China Sea School of Materials Science and EngineeringHainan UniversityHaikou 570228China State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China

Saline water electrolysis is an appealing strategy for hydrogen production,attracting more attention in recent ***-based electrodes exhibit promise as catalysts for saline water ***,they suffer from the inferior service life of the oxygen evolution reaction(OER).Herein,we report an oxygen-evolution electrode consisting of a sulfate-modulated nickel-iron hydroxide(NiFeOOH)affording as the catalytic active layer and Fe-Ni_(3)S_(2) as the corrosion-proof *** developed electrode only requires overpotentials of 220 and 292 mV to deliver the current density of 10 and 500 mA·cm^(−2),*** importantly,it presents long-term stability exceeding 140 and 100 h in 1 M KOH at high current densities of 500 and 1000 mA·cm^(−2),respectively,as well as 120 h for saline water electrolysis at 100 mA·cm^(−2).Experimental results reveal that the generated sulfate plays an indispensable role in improving stability and corrosion *** assembled and tested an anion exchange membrane electrolyzer with Pt/C and NiFeS/NIF as the cathode and anode,respectively,under industrial *** overall water-splitting electrolyzer achieves an impressive energy conversion efficiency of 75%±0.5%.This report offers fresh insights into the design of stable NiFe-based electrodes,which may further promote its practical applications for saline water electrolysis.

关键词： saline water electrolysis oxygen evolution reaction anode material water splitting

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Gasless endoscopic surgery through the upper chest in treatment of thyroid tumor

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Chinese Medical Journal 2011年第10期124卷 1449-1452页

作者： FANG Ju-gao FENG ling YU Zhen-kun li ping-dong han De-min Department of Otolaryngology-Head & Neck Surgery Affiliated Beijing Tongren Hospital Capital Medical University Beijing 100730 China

Background Recently, there has been a surge of interest in minimally invasive techniques with endoscope in thyroid surgery. The aim of this study was to investigate the possibility of a scarless neck surgery under endoscopy for the treatment of thyroid tumor and to observe the results of this *** A total of 68 patients （64 women and 4 men） underwent the surgery. Their ages ranged from 18 to 65 years,with a mean age of （34±3） years. There were 64 cases of thyroid adenoma, and 4 cases of nodular goiter. An incision was made on the surface of the chest bone. The operation cavity was made by dragging the skin. Sixty-four patients underwent partial thyroid lobectomy, four patients underwent thyroid *** All 68 cases showed healing in one stage. None of the cases showed paralysis of the recurrent laryngeal nerve or tumor recurrence within the next 2 to 60 months of follow-up. The patients experienced slight pain after the *** patients were satisfied with the cosmetic results of the *** The gasless endoscopic surgery through the upper chest, which was performed to treat thyroid tumor, did not leave any scar, and was easy to handle, and gave good cosmetic results.

关键词： thyroid neoplasm gasless endoscopic surgery

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A semantic segmentation-based underwater acoustic image transmission framework for cooperative SLAM

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Defence Technology（防务技术） 2024年第3期33卷 339-351页

作者： Jiaxu li Guangyao han Shuai Chang Xiaomei Fu School of Marine Science and Technology Tianjin UniversityTianjin 300072China

With the development of underwater sonar detection technology,simultaneous localization and mapping(SLAM)approach has attracted much attention in underwater navigation field in recent *** the weak detection ability of a single vehicle limits the SLAM performance in wide ***,cooperative SLAM using multiple vehicles has become an important research *** key factor of cooperative SLAM is timely and efficient sonar image transmission among underwater ***,the limited bandwidth of underwater acoustic channels contradicts a large amount of sonar image *** is essential to compress the images before ***,deep neural networks have great value in image compression by virtue of the powerful learning ability of neural networks,but the existing sonar image compression methods based on neural network usually focus on the pixel-level information without the semantic-level *** this paper,we propose a novel underwater acoustic transmission scheme called UAT-SSIC that includes semantic segmentation-based sonar image compression(SSIC)framework and the joint source-channel codec,to improve the accuracy of the semantic information of the reconstructed sonar image at the *** SSIC framework consists of Auto-Encoder structure-based sonar image compression network,which is measured by a semantic segmentation network's *** that sonar images have the characteristics of blurred target edges,the semantic segmentation network used a special dilated convolution neural network(DiCNN)to enhance segmentation accuracy by expanding the range of receptive *** joint source-channel codec with unequal error protection is proposed that adjusts the power level of the transmitted data,which deal with sonar image transmission error caused by the serious underwater acoustic *** results demonstrate that our method preserves more semantic information,with advantages over existing methods at the sa

关键词： Semantic segmentation Sonar image transmission Learning-based compression

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