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An earthquake data acquisition system for mobile ob-servation
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作者 TENG Yun-tian 《Acta Seismologica Sinica(English Edition)》 CSCD 2001年第5期596-599,共4页
Besides the same performance as the earthquake observation system possess used on the fixed earthquake station, such as wide dynamic range, high resolution, following special features are necessary for the earthquake ... Besides the same performance as the earthquake observation system possess used on the fixed earthquake station, such as wide dynamic range, high resolution, following special features are necessary for the earthquake data acquisition system (EDAS) applied for mobile observing in order to suit for running in the field: a) Reliability. The EDAS must work stably long time without being cared. b) Adaptability to the field environments. Earthquake observing in the field often encounters awful environments, such as dampness, dust, and abnormal climate, so how to make the instrument run well in the field circumstance must be considered. c) Ability of anti-vibration. The instrument for outdoor application must keep free from being destroyed during being transported long distance to the destination. d) Storage capacity. Because seismological data is large, how to store and collect the large amount data conveniently from the field is always a difficult point in the mobile observing system design. e) Automation. Timing and positioning automatically is necessary in the field. f) Power consumption. To reduce the power con-sumption as low as possible is very important to the mobile instrument which are powered with battery. g) Ability of testing itself. Testing itself automatically make it convenient in the fieldwork. h) Portability. The instrument must be portable and simply operated. 展开更多
关键词 EARTHQUAKE MOBILE observation data acquisition hardware design software design CLC Number:P315.62 document Id:A Article Id:1000-9116(2001)05-0596-04 Besides the same performance AS the EARTHQUAKE observation system possess used on the fixed EARTHQUAKE station such AS wide dynamic range high resolution following special features are necessary for the EARTHQUAKE data acquisition system (EdAS) applied for MOBILE observing in order to suit for running in the field: a) Reliability. The EdAS MUST work stably long time without BEING cared. b) Adaptability to the FIELd environments. EARTHQUAKE observing in the FIELd often encounters awful environments such AS dampness dust and abnormal climate so how to make the instrument run well in the FIELd circumstance MUST be considered. c) Ability of anti-vibration. The instrument for outdoor application MUST keep free from BEING destroyed during BEING transported long distance to the destination. d) Storage capacity. Because seismological data is large how to store and collect the large amount data conveniently from the FIELd is always a difficult point in the MOBILE observing system design. e) Automation. Timing and positioning automatically is necessary in the field. f) Power consumption. To reduce the power con-sumption AS low AS possible is very important to the MOBILE instrument which are powered with battery. g) Ability of testing itself. Testing itself automatically make it convenient in the fieldwork. h) Portability. The instrument MUST be portable and simply operated.……
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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 ELECTRON POSITRON Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3d Model Schrödinger Equation RMS Klein GORdON Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field density Phase Flow ATTRACTION REPULSION Shell Theorem Ehrenfest VIRIAL Normalization Harmonic Oscillator
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Three-dimensional(3D)parametric measurements of individual gravels in the Gobi region using point cloud technique
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作者 JING Xiangyu HUANG Weiyi KAN Jiangming 《Journal of Arid Land》 SCIE CSCD 2024年第4期500-517,共18页
Gobi spans a large area of China,surpassing the combined expanse of mobile dunes and semi-fixed dunes.Its presence significantly influences the movement of sand and dust.However,the complex origins and diverse materia... Gobi spans a large area of China,surpassing the combined expanse of mobile dunes and semi-fixed dunes.Its presence significantly influences the movement of sand and dust.However,the complex origins and diverse materials constituting the Gobi result in notable differences in saltation processes across various Gobi surfaces.It is challenging to describe these processes according to a uniform morphology.Therefore,it becomes imperative to articulate surface characteristics through parameters such as the three-dimensional(3D)size and shape of gravel.Collecting morphology information for Gobi gravels is essential for studying its genesis and sand saltation.To enhance the efficiency and information yield of gravel parameter measurements,this study conducted field experiments in the Gobi region across Dunhuang City,Guazhou County,and Yumen City(administrated by Jiuquan City),Gansu Province,China in March 2023.A research framework and methodology for measuring 3D parameters of gravel using point cloud were developed,alongside improved calculation formulas for 3D parameters including gravel grain size,volume,flatness,roundness,sphericity,and equivalent grain size.Leveraging multi-view geometry technology for 3D reconstruction allowed for establishing an optimal data acquisition scheme characterized by high point cloud reconstruction efficiency and clear quality.Additionally,the proposed methodology incorporated point cloud clustering,segmentation,and filtering techniques to isolate individual gravel point clouds.Advanced point cloud algorithms,including the Oriented Bounding Box(OBB),point cloud slicing method,and point cloud triangulation,were then deployed to calculate the 3D parameters of individual gravels.These systematic processes allow precise and detailed characterization of individual gravels.For gravel grain size and volume,the correlation coefficients between point cloud and manual measurements all exceeded 0.9000,confirming the feasibility of the proposed methodology for measuring 3D parameters of individual gravels.The proposed workflow yields accurate calculations of relevant parameters for Gobi gravels,providing essential data support for subsequent studies on Gobi environments. 展开更多
关键词 Gobi gravels three-dimensional(3d)parameters point cloud 3d reconstruction Random Sample Consensus(RANSAC)algorithm density-Based Spatial Clustering of Applications with Noise(dBSCAN)
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Databases of 2D material-substrate interfaces and 2D charged building blocks
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作者 邓俊 潘金波 杜世萱 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期34-38,共5页
Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new mater... Discovery of materials using“bottom-up”or“top-down”approach is of great interest in materials science.Layered materials consisting of two-dimensional(2D)building blocks provide a good platform to explore new materials in this respect.In van der Waals(vdW)layered materials,these building blocks are charge neutral and can be isolated from their bulk phase(top-down),but usually grow on substrate.In ionic layered materials,they are charged and usually cannot exist independently but can serve as motifs to construct new materials(bottom-up).In this paper,we introduce our recently constructed databases for 2D material-substrate interface(2DMSI),and 2D charged building blocks.For 2DMSI database,we systematically build a workflow to predict appropriate substrates and their geometries at substrates,and construct the 2DMSI database.For the 2D charged building block database,1208 entries from bulk material database are identified.Information of crystal structure,valence state,source,dimension and so on is provided for each entry with a json format.We also show its application in designing and searching for new functional layered materials.The 2DMSI database,building block database,and designed layered materials are available in Science Data Bank at https://doi.org/10.57760/sciencedb.j00113.00188. 展开更多
关键词 2d material-substrate interfaces charged building block database functional-oriented materials design layered materials density functional theory
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Deep-large faults controlling on the distribution of the venting gas hydrate system in the middle of the Qiongdongnan Basin, South China Sea
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作者 Jin-feng Ren Hai-jun Qiu +6 位作者 Zeng-gui Kuang Ting-wei Li Yu-lin He Meng-jie Xu Xiao-xue Wang Hong-fei Lai Jin Liang 《China Geology》 CAS CSCD 2024年第1期36-50,共15页
Many locations with concentrated hydrates at vents have confirmed the presence of abundant thermogenic gas in the middle of the Qiongdongnan Basin(QDNB).However,the impact of deep structures on gasbearing fluids migra... Many locations with concentrated hydrates at vents have confirmed the presence of abundant thermogenic gas in the middle of the Qiongdongnan Basin(QDNB).However,the impact of deep structures on gasbearing fluids migration and gas hydrates distribution in tectonically inactive regions is still unclear.In this study,the authors apply high-resolution 3D seismic and logging while drilling(LWD)data from the middle of the QDNB to investigate the influence of deep-large faults on gas chimneys and preferred gasescape pipes.The findings reveal the following:(1)Two significant deep-large faults,F1 and F2,developed on the edge of the Songnan Low Uplift,control the dominant migration of thermogenic hydrocarbons and determine the initial locations of gas chimneys.(2)The formation of gas chimneys is likely related to fault activation and reactivation.Gas chimney 1 is primarily arises from convergent fluid migration resulting from the intersection of the two faults,while the gas chimney 2 benefits from a steeper fault plane and shorter migration distance of fault F2.(3)Most gas-escape pipes are situated near the apex of the two faults.Their reactivations facilitate free gas flow into the GHSZ and contribute to the formation of fracture‐filling hydrates. 展开更多
关键词 Venting gas hydrates deep-large faults Gas chimney Gas-escape pipes High-resolution 3d seismic Logging while drilling Qiongdongnan Basin South China Sea
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Metabolic disorders in prediabetes:From mechanisms to therapeutic management
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作者 Wen-Xin Ping Shan Hu +1 位作者 Jing-Qian Su Song-Ying Ouyang 《World Journal of Diabetes》 SCIE 2024年第3期361-377,共17页
Diabetes,one of the world's top ten diseases,is known for its high mortality and complication rates and low cure rate.Prediabetes precedes the onset of diabetes,during which effective treatment can reduce diabetes... Diabetes,one of the world's top ten diseases,is known for its high mortality and complication rates and low cure rate.Prediabetes precedes the onset of diabetes,during which effective treatment can reduce diabetes risk.Prediabetes risk factors include high-calorie and high-fat diets,sedentary lifestyles,and stress.Consequences may include considerable damage to vital organs,including the retina,liver,and kidneys.Interventions for treating prediabetes include a healthy lifestyle diet and pharmacological treatments.However,while these options are effective in the short term,they may fail due to the difficulty of long-term implementation.Medications may also be used to treat prediabetes.This review examines prediabetic treatments,particularly metformin,glucagon-like peptide-1 receptor agonists,sodium glucose cotransporter 2 inhibitors,vitamin D,and herbal medicines.Given the remarkable impact of prediabetes on the progression of diabetes mellitus,it is crucial to intervene promptly and effectively to regulate prediabetes.However,the current body of research on prediabetes is limited,and there is considerable confusion surrounding clinically relevant medications.This paper aims to provide a comprehensive summary of the pathogenesis of prediabetes mellitus and its associated therapeutic drugs.The ultimate goal is to facilitate the clinical utilization of medications and achieve efficient and timely control of diabetes mellitus. 展开更多
关键词 PREdIABETES Glucagon-like peptide agonists Sodium–glucose cotransporter 2 inhibitors Vitamin d Chinese herbal medicines
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Detection of Burned Areas through Spectral Indices Analysis of Sentinel-2A Satellite Images in the Abokouamékro Wildlife Reserve (Central, Côte D’Ivoire)
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作者 Bob Kouakou Kouadio Sié Ouattara +3 位作者 Alain Clément Jean-Marc Gala Bi Zaouri Jean-Luc Kouadio Kouassi Jean-Luc Edouard Kouakou N’guessan 《Open Journal of Applied Sciences》 2024年第1期205-222,共18页
In Côte d’Ivoire, the recurring and unregulated use of bushfires, which cause ecological damage, presents a pressing concern for the custodians of protected areas. This study aims to enhance our comprehension of... In Côte d’Ivoire, the recurring and unregulated use of bushfires, which cause ecological damage, presents a pressing concern for the custodians of protected areas. This study aims to enhance our comprehension of the dynamics of burnt areas within the Abokouamékro Wildlife Reserve (AWR) by employing the analysis of spectral indices derived from satellite imagery. The research methodology began with the calculation of mean indices and their corresponding spectral sub-indices, including NDVI, SAVI, NDWI, NDMI, BAI, NBR, TCW, TCG, and TCB, utilizing data from the Sentinel-2A satellite image dated January 17, 2022. Subsequently, a fuzzy classification model was applied to these various indices and sub-indices, guided by the degree of membership α, with the goal of effectively distinguishing between burned and unburned areas. Following the classification, the accuracies of the classified indices and sub-indices were validated using the coordinates of 100 data points collected within the AWR through GPS technology. The results revealed that the overall accuracy of all indices and sub-indices declines as the degree of membership α decreases from 1 to 0. Among the mean spectral indices, NDVI-mean, SAVI-mean, NDMI-mean exhibited the highest overall accuracies, achieving 97%, 95%, and 90%, respectively. These results closely mirrored those obtained by sub-indices using band 8 (NDVI-B8, SAVI-B8, and NDMI-B8), which yield respective overall accuracies of 93%, 92%, and 89%. At a degree of membership α = 1, the estimated burned areas for the most effective indices encompassed 2144.38 hectares for NDVI-mean, 1932.14 hectares for mean SAVI-mean, and 4947.13 hectares for mean NDMI-mean. A prospective approach involving the amalgamation of these three indices could have the potential to yield improved outcomes. This study could be a substantial contribution to the discrimination of bushfires in Côte d’Ivoire. 展开更多
关键词 Spectral Indices WILdFIRE Burned Areas Abokouamékro Wildlife Reserve Côte d’Ivoire
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3D genome organization and its study in livestock breeding
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作者 Jie Cheng Xiukai Cao +7 位作者 Shengxuan Wang Jiaqiang Zhang Binglin Yue Xiaoyan Zhang Yongzhen Huang Xianyong Lan Gang Ren Hong Chen 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期39-58,共20页
Eukaryotic genomes are hierarchically packaged into cell nucleus,affecting gene regulation.The genome is organized into multiscale structural units,including chromosome territories,compartments,topologically associati... Eukaryotic genomes are hierarchically packaged into cell nucleus,affecting gene regulation.The genome is organized into multiscale structural units,including chromosome territories,compartments,topologically associating domains(TADs),and DNA loops.The identification of these hierarchical structures has benefited from the development of experimental approaches,such as 3C-based methods(Hi-C,ChIA-PET,etc.),imaging tools(2D-FISH,3D-FISH,Cryo-FISH,etc.)and ligation-free methods(GAM,SPRITE,etc.).In recent two decades,numerous studies have shown that the 3D organization of genome plays essential roles in multiple cellular processes via various mechanisms,such as regulating enhancer activity and promoter-enhancer interactions.However,there are relatively few studies about the 3D genome in livestock species.Therefore,studies for exploring the function of 3D genomes in livestock are urgently needed to provide a more comprehensive understanding of potential relationships between the genome and production traits.In this review,we summarize the recent advances of 3D genomics and its biological functions in human and mouse studies,drawing inspiration to explore the 3D genomics of livestock species.We then mainly focus on the biological functions of 3D genome organization in muscle development and its implications in animal breeding. 展开更多
关键词 3d genome organization 3d genomic methodology regulatory mechanisms muscle development livestock breeding
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Automatic modulation recognition of radio fuzes using a DR2D-based adaptive denoising method and textural feature extraction
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作者 Yangtian Liu Xiaopeng Yan +2 位作者 Qiang Liu Tai An Jian Dai 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第4期328-338,共11页
The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference systems.However,the electromagnetic environment of modern battlefields is complex,and the signal-to-n... The identification of intercepted radio fuze modulation types is a prerequisite for decision-making in interference systems.However,the electromagnetic environment of modern battlefields is complex,and the signal-to-noise ratio(SNR)of such environments is usually low,which makes it difficult to implement accurate recognition of radio fuzes.To solve the above problem,a radio fuze automatic modulation recognition(AMR)method for low-SNR environments is proposed.First,an adaptive denoising algorithm based on data rearrangement and the two-dimensional(2D)fast Fourier transform(FFT)(DR2D)is used to reduce the noise of the intercepted radio fuze intermediate frequency(IF)signal.Then,the textural features of the denoised IF signal rearranged data matrix are extracted from the statistical indicator vectors of gray-level cooccurrence matrices(GLCMs),and support vector machines(SVMs)are used for classification.The DR2D-based adaptive denoising algorithm achieves an average correlation coefficient of more than 0.76 for ten fuze types under SNRs of-10 d B and above,which is higher than that of other typical algorithms.The trained SVM classification model achieves an average recognition accuracy of more than 96%on seven modulation types and recognition accuracies of more than 94%on each modulation type under SNRs of-12 d B and above,which represents a good AMR performance of radio fuzes under low SNRs. 展开更多
关键词 Automatic modulation recognition Adaptive denoising data rearrangement and the 2d FFT(dR2d) Radio fuze
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3D‑Printed Carbon‑Based Conformal Electromagnetic Interference Shielding Module for Integrated Electronics
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作者 Shaohong Shi Yuheng Jiang +5 位作者 Hao Ren Siwen Deng Jianping Sun Fangchao Cheng Jingjing Jing Yinghong Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期87-101,共15页
Electromagnetic interference shielding(EMI SE)modules are the core com-ponent of modern electronics.However,the tra-ditional metal-based SE modules always take up indispensable three-dimensional space inside electroni... Electromagnetic interference shielding(EMI SE)modules are the core com-ponent of modern electronics.However,the tra-ditional metal-based SE modules always take up indispensable three-dimensional space inside electronics,posing a major obstacle to the integra-tion of electronics.The innovation of integrating 3D-printed conformal shielding(c-SE)modules with packaging materials onto core electronics offers infinite possibilities to satisfy ideal SE func-tion without occupying additional space.Herein,the 3D printable carbon-based inks with various proportions of graphene and carbon nanotube nanoparticles are well-formulated by manipulating their rheological peculiarity.Accordingly,the free-constructed architectures with arbitrarily-customized structure and multifunctionality are created via 3D printing.In particular,the SE performance of 3D-printed frame is up to 61.4 dB,simultaneously accompanied with an ultralight architecture of 0.076 g cm^(-3) and a superhigh specific shielding of 802.4 dB cm3 g^(-1).Moreover,as a proof-of-concept,the 3D-printed c-SE module is in situ integrated into core electronics,successfully replacing the traditional metal-based module to afford multiple functions for electromagnetic compatibility and thermal dissipa-tion.Thus,this scientific innovation completely makes up the blank for assembling carbon-based c-SE modules and sheds a brilliant light on developing the next generation of high-performance shielding materials with arbitrarily-customized structure for integrated electronics. 展开更多
关键词 3d printing Carbon-based nanoparticles Conformal electromagnetic interference shielding Integrated electronics
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3D bioprinting of in vitro porous hepatoma models:establishment,evaluation,and anticancer drug testing
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作者 Xiaoyuan Wang Zixian Liu +7 位作者 Qianqian Duan Boye Zhang Yanyan Cao Zhizhong Shen Meng Li Yanfeng Xi Jianming Wang Shengbo Sang 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第2期137-152,共16页
Traditional tumor models do not tend to accurately simulate tumor growth in vitro or enable personalized treatment and are particularly unable to discover more beneficial targeted drugs.To address this,this study desc... Traditional tumor models do not tend to accurately simulate tumor growth in vitro or enable personalized treatment and are particularly unable to discover more beneficial targeted drugs.To address this,this study describes the use of threedimensional(3D)bioprinting technology to construct a 3D model with human hepatocarcinoma SMMC-7721 cells(3DP-7721)by combining gelatin methacrylate(GelMA)and poly(ethylene oxide)(PEO)as two immiscible aqueous phases to form a bioink and innovatively applying fluorescent carbon quantum dots for long-term tracking of cells.The GelMA(10%,mass fraction)and PEO(1.6%,mass fraction)hydrogel with 3:1 volume ratio offered distinct pore-forming characteristics,satisfactorymechanical properties,and biocompatibility for the creation of the 3DP-7721 model.Immunofluorescence analysis and quantitative real-time fluorescence polymerase chain reaction(PCR)were used to evaluate the biological properties of the model.Compared with the two-dimensional culture cell model(2D-7721)and the 3D mixed culture cell model(3DM-7721),3DP-7721 significantly improved the proliferation of cells and expression of tumor-related proteins and genes.Moreover,we evaluated the differences between the three culture models and the effectiveness of antitumor drugs in the three models and discovered that the efficacy of antitumor drugs varied because of significant differences in resistance proteins and genes between the three models.In addition,the comparison of tumor formation in the three models found that the cells cultured by the 3DP-7721 model had strong tumorigenicity in nude mice.Immunohistochemical evaluation of the levels of biochemical indicators related to the formation of solid tumors showed that the 3DP-7721 model group exhibited pathological characteristics of malignant tumors,the generated solid tumors were similar to actual tumors,and the deterioration was higher.This research therefore acts as a foundation for the application of 3DP-7721 models in drug development research. 展开更多
关键词 3d bioprinting Hepatoma tumor models drug screening Antitumor drug development
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Development of CONTHAC-3D and hydrogen distribution analysis of HPR1000
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作者 Hui Wang Jing-Jing Li +2 位作者 Yuan Chang Gong-Lin Li Ming Ding 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期210-221,共12页
An in-house code,CONTHAC-3D,was developed to calculate and analyze thermal-hydraulic phenomena in containments during severe accidents.CONTHAC-3D is a three-dimensional computational fluid dynamics code that can be ap... An in-house code,CONTHAC-3D,was developed to calculate and analyze thermal-hydraulic phenomena in containments during severe accidents.CONTHAC-3D is a three-dimensional computational fluid dynamics code that can be applied to predict gas flow,diffusion,and steam condensation in a containment during a severe hypothetical accident,as well as to obtain an estimate of the local hydrogen concentration in various zones of the containment.CONTHAC-3D was developed using multiple models to simulate the features of the proprietary systems and equipment of HPR1000 and ACP100,such as the passive cooling system,passive autocatalytic recombiners and the passive air cooling system.To validate CONTHAC-3D,a GX6 test was performed at the Battelle Model Containment facility.The hydrogen concentration and temperature monitored by the GX6 test are accurately predicted by CONTHAC-3D.Subsequently,the hydrogen distribution in the HPR1000 containment during a severe accident was studied.The results show that the hydrogen removal rates calculated using CONTHAC-3D for different types of PARs agree well with the theoretical values,with an error of less than 1%.As the accident progresses,the hydrogen concentration in the lower compartment becomes higher than that in the large space,which implies that the lower compartment has a higher hydrogen risk than the dome and large space at a later stage of the accident.The amount of hydrogen removed by the PARs placed on the floor of the compartment is small;therefore,raising the installation height of these recombiners appropriately is recommended.However,we do not recommend installing all autocatalytic recombiners at high positions.The study findings in regard to the hydrogen distribution in the HPR1000 containment indicate that CONTHAC-3D can be applied to the study of hydrogen risk containment. 展开更多
关键词 Hydrogen risk mitigation Pressurized water reactor HPR1000 Thermal hydraulic CONTHAC-3d
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Damage evolution of rock-encased-backfill structure under stepwise cyclic triaxial loading
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作者 Xin Yu Yuye Tan +4 位作者 Weidong Song John Kemeny Shengwen Qi Bowen Zheng Songfeng Guo 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第2期597-615,共19页
Rock-encased-backfill(RB)structures are common in underground mining,for example in the cut-andfill and stoping methods.To understand the effects of cyclic excavation and blasting activities on the damage of these RB ... Rock-encased-backfill(RB)structures are common in underground mining,for example in the cut-andfill and stoping methods.To understand the effects of cyclic excavation and blasting activities on the damage of these RB structures,a series of triaxial stepwise-increasing-amplitude cyclic loading experiments was conducted with cylindrical RB specimens(rock on outside,backfill on inside)with different volume fractions of rock(VF=0.48,0.61,0.73,and 0.84),confining pressures(0,6,9,and 12 MPa),and cyclic loading rates(200,300,400,and 500 N/s).The damage evolution and meso-crack formation during the cyclic tests were analyzed with results from stress-strain hysteresis loops,acoustic emission events,and post-failure X-ray 3D fracture morphology.The results showed significant differences between cyclic and monotonic loadings of RB specimens,particularly with regard to the generation of shear microcracks,the development of stress memory and strain hardening,and the contact forces and associated friction that develops along the rock-backfill interface.One important finding is that as a function of the number of cycles,the elastic strain increases linearly and the dissipated energy increases exponentially.Also,compared with monotonic loading,the cyclic strain hardening characteristics are more sensitive to rising confining pressures during the initial compaction stage.Another finding is that compared with monotonic loading,more shear microcracks are generated during every reloading stage,but these microcracks tend to be dispersed and lessen the likelihood of large shear fracture formation.The transition from elastic to plastic behavior varies depending on the parameters of each test(confinement,volume fraction,and cyclic rate),and an interesting finding was that the transformation to plastic behavior is significantly lower under the conditions of 0.73 rock volume fraction,400 N/s cyclic loading rate,and 9 MPa confinement.All the findings have important practical implications on the ability of backfill to support underground excavations. 展开更多
关键词 Rock and backfill Triaxial cyclic loading Volume fraction damage evolution 3d visualization
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Highly Efficient Aligned Ion‑Conducting Network and Interface Chemistries for Depolarized All‑Solid‑State Lithium Metal Batteries
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作者 Yongbiao Mu Shixiang Yu +12 位作者 Yuzhu Chen Youqi Chu Buke Wu Qing Zhang Binbin Guo Lingfeng Zou Ruijie Zhang Fenghua Yu Meisheng Han Meng Lin Jinglei Yang Jiaming Bai Lin Zeng 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期102-119,共18页
Improving the long-term cycling stability and energy density of all-solid-state lithium(Li)-metal batteries(ASSLMBs)at room temperature is a severe challenge because of the notorious solid–solid interfacial contact l... Improving the long-term cycling stability and energy density of all-solid-state lithium(Li)-metal batteries(ASSLMBs)at room temperature is a severe challenge because of the notorious solid–solid interfacial contact loss and sluggish ion transport.Solid electrolytes are generally studied as two-dimensional(2D)structures with planar interfaces,showing limited interfacial contact and further resulting in unstable Li/electrolyte and cathode/electrolyte interfaces.Herein,three-dimensional(3D)architecturally designed composite solid electrolytes are developed with independently controlled structural factors using 3D printing processing and post-curing treatment.Multiple-type electrolyte films with vertical-aligned micro-pillar(p-3DSE)and spiral(s-3DSE)structures are rationally designed and developed,which can be employed for both Li metal anode and cathode in terms of accelerating the Li+transport within electrodes and reinforcing the interfacial adhesion.The printed p-3DSE delivers robust long-term cycle life of up to 2600 cycles and a high critical current density of 1.92 mA cm^(−2).The optimized electrolyte structure could lead to ASSLMBs with a superior full-cell areal capacity of 2.75 mAh cm^(−2)(LFP)and 3.92 mAh cm^(−2)(NCM811).This unique design provides enhancements for both anode and cathode electrodes,thereby alleviating interfacial degradation induced by dendrite growth and contact loss.The approach in this study opens a new design strategy for advanced composite solid polymer electrolytes in ASSLMBs operating under high rates/capacities and room temperature. 展开更多
关键词 All-solid-state lithium metal batteries Composite solid electrolyte 3d printing Areal capacity Interfacial degradation
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An integrated spatial planning of the mountainous landscapes for ski sports in a case area at the eastern Türkiye
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作者 SATIR Onur TOSUN Busra +2 位作者 COSKUN OZYOL Funda OZDEMIR Omer Faruk BERBEROGLU Suha 《Journal of Mountain Science》 SCIE CSCD 2024年第3期754-767,共14页
Mountainous regions have disadvantages in economic development because of harsh physical and climatic conditions.However,winter tourism activities are one of the key components for supporting economic development in t... Mountainous regions have disadvantages in economic development because of harsh physical and climatic conditions.However,winter tourism activities are one of the key components for supporting economic development in the highlands.Establishing a ski resort area supports direct and indirect employment in a region,and it stops immigration from mountainous regions to other places.This research aimed to assess the potential ski areas using a multi criteria evaluation technique in the Van region which is located in the eastern part of Türkiye.In this context,snow cover duration,sun effect,slope,slope length,elevation,population density,distance from main roads and lake visibility were used as input factors in the decision making process.Each factor was standardized using a fuzzy technique based on existing well-known ski centers in Türkiye.The weight of inputs was defined by applying a survey to the professional skiers.The most important factors were detected as transportation opportunities and snow covers whereas,the least important factors were elevation and population density.Additionally,lake visibility was very important to make a difference from other existing facilities in the region.Therefore,it was included as constraints and lake visible areas were extracted at the final stage of the research.Potential ski areas were mapped in three levels as professional,intermediate and beginner skiers.One of the suitable areas was selected as a sample projection and for the 3D simulation of the ski investment area.Potential costs and benefits were discussed.It was found that a ski tourism area investment can be amortized in 3 years in the region. 展开更多
关键词 Winter sports and tourism decision making 3d simulation and modelling Landscape planning GIS
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Vitamin D,selenium,and antidiabetic drugs in the treatment of type 2 diabetes mellitus with Hashimoto's thyroiditis
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作者 Fen Feng Bin Zhou +3 位作者 Ci-La Zhou Ping Huang Gang Wang Kuang Yao 《World Journal of Diabetes》 SCIE 2024年第2期209-219,共11页
BACKGROUND Diabetes and thyroiditis are closely related.They occur in combination and cause significant damage to the body.There is no clear treatment for type-2 diabetes mellitus(T2DM)with Hashimoto's thyroiditis... BACKGROUND Diabetes and thyroiditis are closely related.They occur in combination and cause significant damage to the body.There is no clear treatment for type-2 diabetes mellitus(T2DM)with Hashimoto's thyroiditis(HT).While single symptomatic drug treatment of the two diseases is less effective,combined drug treatment may improve efficacy.AIM To investigate the effect of a combination of vitamin D,selenium,and hypoglycemic agents in T2DM with HT.METHODS This retrospective study included 150 patients with T2DM and HT treated at The Central Hospital of Shaoyang from March 2020 to February 2023.Fifty patients were assigned to the control group,test group A,and test group B according to different treatment methods.The control group received low-iodine diet guidance and hypoglycemic drug treatment.Test group A received the control treatment plus vitamin D treatment.Test group B received the group A treatment plus selenium.Blood levels of markers of thyroid function[free T3(FT3),thyroid stimulating hormone(TSH),free T4(FT4)],autoantibodies[thyroid peroxidase antibody(TPOAB)and thyroid globulin antibody(TGAB)],blood lipid index[low-density lipoprotein cholesterol(LDL-C),total cholesterol(TC),triacylglycerol(TG)],blood glucose index[fasting blood glucose(FBG),and hemoglobin A1c(HbA1c)]were measured pre-treatment and 3 and 6 months after treatment.The relationships between serum 25-hydroxyvitamin D3[25(OH)D3]level and each of these indices were analyzed.RESULTS The levels of 25(OH)D3,FT3,FT4,and LDL-C increased in the order of the control group,test group A,and test group B(all P<0.05).The TPOAB,TGAB,TC,TG,FBG,HbA1c,and TSH levels increased in the order of test groups B,A,and the control group(all P<0.05).All the above indices were compared after 3 and 6 months of treatment.Pre-treatment,there was no divergence in serum 25(OH)D3 level,thyroid function-related indexes,autoantibodies level,blood glucose,and blood lipid index between the control group,test groups A and B(all P>0.05).The 25(OH)D3 levels in test groups A and B were negatively correlated with FT4 and TGAB(all P<0.05).CONCLUSION The combination drug treatment for T2DM with HT significantly improved thyroid function,autoantibody,and blood glucose and lipid levels. 展开更多
关键词 Type-2 diabetes mellitus Hashimoto's thyroiditis Vitamin d Selenium agent Hypoglycemic drugs Curative effect
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Identifying the enhancement mechanism of Al/MoO_(3) reactive multilayered films on the ignition ability of semiconductor bridge using a one-dimensional gas-solid two-phase flow model
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作者 Jianbing Xu Yuxuan Zhou +3 位作者 Yun Shen Yueting Wang Yinghua Ye Ruiqi Shen 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第3期168-179,共12页
Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics device.Understanding the ignition enhancement m... Energetic Semiconductor bridge(ESCB)based on reactive multilayered films(RMFs)has a promising application in the miniature and intelligence of initiator and pyrotechnics device.Understanding the ignition enhancement mechanism of RMFs on semiconductor bridge(SCB)during the ignition process is crucial for the engineering and practical application of advanced initiator and pyrotechnics devices.In this study,a one-dimensional(1D)gas-solid two-phase flow ignition model was established to study the ignition process of ESCB to charge particles based on the reactivity of Al/MoO_(3) RMFs.In order to fully consider the coupled exothermic between the RMFs and the SCB plasma during the ignition process,the heat release of chemical reaction in RMFs was used as an internal heat source in this model.It is found that the exothermal reaction in RMFs improved the ignition performance of SCB.In the process of plasma rapid condensation with heat release,the product of RMFs enhanced the heat transfer process between the gas phase and the solid charge particle,which accelerated the expansion of hot plasma,and heated the solid charge particle as well as gas phase region with low temperature.In addition,it made up for pressure loss in the gas phase.During the plasma dissipation process,the exothermal chemical reaction in RMFs acted as the main heating source to heat the charge particle,making the surface temperature of the charge particle,gas pressure,and gas temperature rise continuously.This result may yield significant advantages in providing a universal ignition model for miniaturized ignition devices. 展开更多
关键词 Ignition enhancement mechanism 1d gas-solid two-phase flow Al/MoO_(3)reactive multilayered films Semiconductor bridge Miniaturized ignition device
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Influence of Hemoglobin S Haplotypes on the Responses to Hydroxyurea Treatment in Children with Sickle Cell Disease in Abidjan, Côte d’Ivoire
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作者 Mireille Aye-Yayo Vincent Yapo +5 位作者 Boidy Kouakou Missa Louis Adjé Adia Eusèbe Adjambri Ebah Hermance Kassi Taïratou Kamagate Duni Sawadogo 《Open Journal of Genetics》 CAS 2024年第1期1-12,共12页
Background: In Côte d’Ivoire so far, the circulating haplotypes have been inferred on the phenotypic profiling of SCD patients. The impact of the circulating haplotypes on the use of Hydroxyurea has not been ass... Background: In Côte d’Ivoire so far, the circulating haplotypes have been inferred on the phenotypic profiling of SCD patients. The impact of the circulating haplotypes on the use of Hydroxyurea has not been assessed yet. Therefore the objective of this study is to identify in Abidjan the HbS haplotypes that modulate HU treatment responses. Methods: In a cross-sectional descriptive and analytical study, children aged 5 to 15 years with SCD, and carrying the hemoglobin phenotypes SSFA2 and SFA2, were recruited into a HU treatment cohort. Various parameters on the haplotypes and the outcomes of the treatment were analyzed. Results: Thirty nine children with SCD were included. The phenotypic profile of the cohort was 86.6% of SSFA2 and 15.4% of SFA2. Three haplotypes were found, the Benin haplotype, the Senegal haplotype, and an atypical one. The participants belonged to three genotypes, Benin/atypical (64.1%), Benin/Senegal (33.3%) and Senegal/Senegal (2.6%). Overall, HU treatment was successful in all haplotypes with 12 out of 39 patients failing treatment after 12 months in the Benin haplotype group. The association between HU treatment success and the Benin haplotype was found in terms of the decrease in the number of white blood cells and the students missing class. Conclusion: The study revealed that inferring haplotype based on the phenotypic profile could be inaccurate. The proportion of atypical haplotype that were not previously described in Côte d’Ivoire was high. All the haplotypes seemed to be associated with HU treatment success but some patients with Benin haplotype did not respond well. 展开更多
关键词 Sickle Cell disease CHILdREN HAPLOTYPE HYdROXYUREA Côte d’Ivoire
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A New Three-Dimensional(3D)Printing Prepress Algorithm for Simulation of Planned Surgery for Congenital Heart Disease
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作者 Vitaliy Suvorov Olga Loboda +1 位作者 Maria Balakina Igor Kulczycki 《Congenital Heart Disease》 SCIE 2023年第5期491-505,共15页
Background:Three-dimensional printing technology may become a key factor in transforming clinical practice and in significant improvement of treatment outcomes.The introduction of this technique into pediatric cardiac... Background:Three-dimensional printing technology may become a key factor in transforming clinical practice and in significant improvement of treatment outcomes.The introduction of this technique into pediatric cardiac surgery will allow us to study features of the anatomy and spatial relations of a defect and to simulate the optimal surgical repair on a printed model in every individual case.Methods:We performed the prospective cohort study which included 29 children with congenital heart defects.The hearts and the great vessels were modeled and printed out.Measurements of the same cardiac areas were taken in the same planes and points at multislice computed tomography images(group 1)and on printed 3D models of the hearts(group 2).Pre-printing treatment of the multislice computed tomography data and 3D model preparation were performed according to a newly developed algorithm.Results:The measurements taken on the 3D-printed cardiac models and the tomographic images did not differ significantly,which allowed us to conclude that the models were highly accurate and informative.The new algorithm greatly simplifies and speeds up the preparation of a 3D model for printing,while maintaining high accuracy and level of detail.Conclusions:The 3D-printed models provide an accurate preoperative assessment of the anatomy of a defect in each case.The new algorithm has several important advantages over other available programs.They enable the development of customized preliminary plans for surgical repair of each specific complex congenital heart disease,predict possible issues,determine the optimal surgical tactics,and significantly improve surgical outcomes. 展开更多
关键词 3d printing imaging in cardiac surgery congenital heart disease modelling in cardiac surgery pediatric cardiology algorithmic modelling of the heart medical imaging 3d modelling
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Evaluation of the Use of Long-Lasting Impregnated Mosquito Nets (LLINs) in the Health District of Dimbokro (Center of Côte d’Ivoire)
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作者 Ellélé Aimé Marius Yapi Tanoh Amany Serge Raymond N’krumah +4 位作者 Bi Yourou Guillaume Zamina Martial Bama Assikohon Pulchérie Gouzilé Amoin Nadège Abo Issaka Tiembre 《Journal of Biosciences and Medicines》 2024年第3期44-61,共18页
The Dimbokro health district has one of the highest incidences of malaria in Côte d’Ivoire, despite numerous campaigns to distribute Long-Acting Impregnated Mosquito Nets (LLINs). Given this observation, what ar... The Dimbokro health district has one of the highest incidences of malaria in Côte d’Ivoire, despite numerous campaigns to distribute Long-Acting Impregnated Mosquito Nets (LLINs). Given this observation, what are the population’s attitudes towards LLINs that could explain the high endemicity of malaria in Dimbokro? The aim of this study is to assess the knowledge, attitudes and practices of people in the health area of Nofou, one of the villages in the Dimbokro health district where malaria is most prevalent, with a view to strengthening malaria control strategies. A collection of historical health data (malaria cases and LLIN usage rates) and a cross-sectional questionnaire survey was carried out from July 20 to August 03, 2022 in 400 households selected by systematic random sampling. Data were entered using Epi Info 7 and multivariate statistical analyses were performed using IBM SPSS 22 software. In the Dimbokro health district, the rate of LLIN use was negatively correlated (r = -0.771) with malaria incidence over the six years of historical data collection. Households had an average of 53% good knowledge, 68.6% good practices and 28.4% good attitudes towards LLINs. The study also revealed that the main factors explaining LLIN use in the Nofou health area are mosquito bite (ORa = 5.29 (1.12 - 25.04)), age of household members (ORa = 1.07 (1.01 - 1.14)) and marital status (ORa = 8.45 (1.70 - 45.02)). Awareness-raising on the use of LLINs should be intensified in the Dimbokro health district. Other control strategies, such as vector control and environmental sanitation, should be considered to combat malaria. 展开更多
关键词 MALARIA LLINs Knowledge ATTITUdES PRACTICES dimbokro Côte d’Ivoire
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