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Resolution Enhancement of SOHO/MDI Magnetograms

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Research in Astronomy and Astrophysics 2024年第6期24卷 358-367页

作者： Ying Qin Kai-Fan Ji hui Liu xiao-guang Yu Yunnan Observatories Chinese Academy of SciencesKunming 650011China University of Chinese Academy of Sciences Beijing 100049China Yunnan Key Laboratory of Solar Physics and Space Science Kunming 650216China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China

Research on the solar magnetic field and its effects on solar dynamo mechanisms and space weather events has benefited from the continual improvements in instrument resolution and measurement *** augmentation and assimilation of historical observational data timelines also play a significant role in understanding the patterns of solar magnetic field *** the realm of astronomical data processing,super-resolution(SR)reconstruction refers to the process of using a substantial corpus of training data to learn the nonlinear mapping between low-resolution(LR)and high-resolution(HR)images,thereby achieving higherresolution astronomical *** paper is an application study in high-dimensional nonlinear *** learning models were employed to perform SR modeling on SOHO/MDI magnetograms and SDO/HMI magnetograms,thus reliably achieving resolution enhancement of full-disk SOHO/MDI magnetograms and enhancing the image resolution to obtain more detailed *** this study,a data set comprising 9717pairs of data from 2010 April to 2011 February was used as the training set,1332 pairs from 2011 March were used as the validation set and 1034 pairs from 2011 April were used as the test *** data preprocessing,we randomly cropped 128×128 sub-images as the LR cases from the full-disk MDI magnetograms,and the corresponding 512×512 sub-images as HR ones from the HMI full-disk magnetograms for model *** tests conducted have shown that the study successfully produced reliable 4×SR reconstruction of full-disk MDI *** MESR model's results(0.911)were highly correlated with the target HMI magnetographs as indicated by the correlation coefficient ***,the method achieved the best PSNR,SSIM,MAE and RMSE values,indicating that the MESR model can effectively reconstruct magnetograms.

关键词： magnetic fields techniques:image processing virtual observatory tools Sun:magnetic fields

Effect of Mn addition on microstructure and mechanical properties of GX40CrNiSi25-12 austenitic heat resistant steel

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China Foundry 2024年第3期21卷 205-212页

作者： Guan-yu Jiang Meng-wu Wu xiao-guang Yang hui Wang Yu-yuan Zhu Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 441000HubeiChina Wescast Industries(China)Co. Ltd.Wuhan 430100China

Three types of steels were designed on the basis of GX40CrNiSi25-12 austenitic heat resistant steel by adding different Mn contents(2wt.%,6wt.%,and 12wt.%).Thermodynamic calculation,microstructure characterization and mechanical property tests were conducted to investigate the effect of Mn addition on the microstructure and mechanical properties of the austenitic heat resistant *** show that the matrix structure in all the three types of steels at room temperature is completely *** NbC and M_(23)C_(6)precipitate at grain boundaries of austenite *** the increase of Mn content,the number of carbides increases and their distribution becomes more *** the Mn content increases from 1.99%to 12.06%,the ultimate tensile strength,yield strength and elongation increase by 14.6%,8.0%and 46.3%,*** improvement of the mechanical properties of austenitic steels can be explained by utilizing classic theories of alloy strengthening,including solid solution strengthening,precipitation strengthening,and grain *** increase in alloy strength can be attributed to solid solution strengthening and precipitation strengthening caused by the addition of *** improvement of the plasticity of austenitic steels can be explained from two aspects:grain refinement and homogenization of precipitated phases.

关键词： austenitic heat resistant steel manganese microstructure mechanical properties

Ethical concerns in aging research:perspectives of global frontline researchers

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Science China(Life Sciences) 2024年第10期67卷 2149-2156页

作者： Yaojin Peng Lulu Ding Zhenyu xiao Moshi Song Jianwei Lv guang-hui Liu Key Laboratory of Organ Regeneration and Reconstruction State Key Laboratory of Stem Cell and Reproductive BiologyInstitute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China Aging Biomarker Consortium(ABC) Beijing 100101China School of Life Science Beijing Institute of TechnologyBeijing 100081China School of Life Sciences Xiamen UniversityXiamen 361102China Advanced Innovation Center for Human Brain Protection and National Clinical Research Center for Geriatric Disorders Xuanwu HospitalCapital Medical UniversityBeijing 100053China Aging Translational Medicine Center International Center for Aging and CancerBeijing Municipal Geriatric Medical Research CenterXuanwu HospitalCapital Medical UniversityBeijing 100053China

This study investigated the ethical landscape of aging research amid the increasing global focus on extending the human lifespan and health *** global survey of 180 researchers across 38 jurisdictions revealed divergent perceptions of aging,a consensus regarding the feasibility of delaying aging,and multiple perspectives regarding lifespan *** present findings underscore a paradigm shift toward inclusive and ethically sound research,emphasizing the need for an approach that strikes a balance between basic and clinical *** addition,this study highlighted key ethical concerns in aging research,including the effects of misleading advertising,potential inequality in access to aging interventions,and risks pertaining to the extrapolation of research findings from lower-model organisms to *** insights presented in this paper call for an integrated approach for overcoming the complex ethical and societal challenges in aging research to ensure responsible and equitable advancements in this burgeoning field.

关键词： aging ethical landscape ethics surveys and questionnaires

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Metamorphic P-T conditions and ages of garnet-biotite schists in the Dahongshan Group from the southwestern Yangtze Block

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Acta Geochimica 2024年第4期43卷 707-718页

作者： Jun-xiao Ma guang-shu Yang Yong-feng Yan xiao-Fei Xu Yun-hua Ren hui Zhao xiao-jun Zheng Yuan Qin Faculty of Land Resources Engineering Kunming University of Science and TechnologyKunming 650093China Geological Team 306 of Yunnan Non-Ferrous Metals Geological Bureau Kunming 650217China Yunnan Provincial Bureau of Non-Ferrous Geology Kunming 650051China

The Dahongshan Group,situated at the southwestern margin of the Yangtze Block,represents a geological unit characterized by relatively high-grade metamorphism in the *** paper investigates the garnet-biotite schist from the Laochanghe Formation of the Dahongshan Group,employing an integrated approach that includes petrological analysis,phase equilibrium modeling,and zircon U-Pb *** schist is mainly composed of garnet,biotite,plagioclase,quartz,rutile,and *** equilibrium modeling revealed the peak metamorphic conditions of 8-9 kbar and 635-675°*** further integrating the prograde metamorphic profile of garnet and geothermobarometric results,a clockwise P-T metamorphic evolution path is constructed,which includes an increase in temperature and pressure during the prograde ***-ICP-MS zircon U-Pb dating and zircon Ti thermometry constrains the post-peak metamorphic age of 831.2±7.2 *** with previously reported results,it is revealed that the southwestern margin of the Yangtze Block experienced a large-scale regional metamorphism during the Neoproterozoic(890-750 Ma),which is related to the collisional orogenic *** may be associated with the late-stage assembly of the Rodinia supercontinent or with local compression and subduction processes during the breakup of the Rodinia supercontinent.

关键词： Southwestern Yangtze Block Dahongshan Group Phase equilibrium modeling Zircon U-Pb dating Neoproterozoic metamorphism

Acoustic characterization of hydrate formation and decomposition in clay-bearing sediments

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Petroleum Science 2024年第4期21卷 2830-2838页

作者： Yi-Jian Zhu xiao-Mei Yang Xing Huang Hao Li xiao-hui Wang Yi-Fei Sun Peng xiao Chang-Yu Sun guang-Jin Chen State Key Laboratory of Heavy Oil Processing College of Chemical Engineering and Environment China University of Petroleum

Understanding the acoustic characteristics of hydrates in various sediments is crucial for hydrate resource detection and safe and efficient exploitation, as hydrate occurrence patterns vary greatly in different sediments. In this work, sediments with different bentonite contents, water saturations, and types were prepared to investigate the characteristics of P-wave velocity(reflecting the magnitude of hydrate saturation in the sediment) and amplitude(reflecting the degree of hydrate-sediment cementation) during hydrate formation and depressurization. During hydrate formation, the P-wave velocity and amplitude have similar trends. As clay content increases, the P-wave velocity increase rates quickened. On the other hand, the increased rate of P-wave velocity slows down with the increase of water saturation in the clay-bearing sediments. Comparing various types of sediment shows that the water absorption and swelling of bentonite reduce the pore space, speeding up the cementation of the hydrate with the sediment and increasing P-wave velocity at a faster rate. Correspondence between P-wave velocity and hydrate saturation is strongly related to sediment type, clay content, and water *** rapidly decreasing amplitude in the early stage of hydrate depressurization indicates that hydrate in clay-bearing sediments is weakly cemented to the sediments, which is prone to stratigraphic *** findings of this study offer guidance for hydrate resource assessments in clay-bearing sediments as well as geologic risk estimations during hydrate mining.

关键词： Gas hydrate Bentonite Illite P-wave velocity Amplitude

Bioinspired design of integral molded Janus silk fibroin-MXene evaporator for efficient solar vapor generation

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Nano Research 2024年第4期17卷 2824-2835页

作者： Ling-Qing Kong Zhi-Cheng Zeng guang-Zong Min Zhao-hui Meng Guo-Qing Meng xiao-xiao Guo Nai-Bo Lin Xiang-Yang Liu The Higher Educational Key Laboratory for Biomedical Engineering of Fujian Province Research Center of Biomedical Engineering of XiamenDepartment of BiomaterialsCollege of MaterialsXiamen UniversityXiamen 361005China The State Key Laboratory of Marine Environmental Science(MEL) College of Ocean and Earth SciencesXiamen UniversityXiamen 361005China

Solar vapor generation is a promising sustainable technology that uses solar distillation to produce fresh water from seawater and wastewater,helping relieve global water resource ***,inspired by naturally grown integrally molded mulberry leaves with a Janus hydrophilic and hydrophobic structure,a novel,simple,and efficient integrated molding method is proposed to break through the limitations of the traditional split manufacturing strategy and realizes the integrated formation of Janus *** on the spontaneous sedimentation characteristics of MXene in silk fibroin solution and its regulation of mesoscopic structure and hydrophilicity of silk fibroin,layered structures with different compositions and hydrophilicities were obtained in one ***,ethanol and glutaraldehyde were added to construct a physical crystallization-chemical crosslinking dual stabilization structure in silk *** evaporator has the evaporation rate of 3.07 kg·m^(-2)·h^(-1) and the efficiency of 86.8%under 1 sun and maintains high evaporation performance under various extreme test conditions including vigorous washing,repeated compression,and high-intensity ultraviolet(UV)***,the evaporator performs well in practical application scenarios,its evaporation rate in the simulated Dead Sea seawater exceeds 2.13 kg·m^(-2)·h^(-1),and more than 99.9%of the salt,heavy metal ions,oil pollution,and dyes are purified.

关键词： silk fibroin MXene bioinspired integrated molding Janus structure solar vapor generation

Roles of Cu doping in YbZn_(2)Sb_(2) for thermoelectric performance enhancement

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Rare Metals 2024年第6期43卷 2869-2875页

作者： Xiong Zhang Hai-hui Li xiao-Liang Cao Bin Zhang Hong Wu Yu Zhang guang Han Guo-Yu Wang Hao-Shuang Gu xiao-Yuan Zhou College of Physics and Electronic Science Hubei Normal UniversityHuangshi 435002China Analytical and Testing Center Chongqing UniversityChongqing401331China School of Science Chongqing University of Posts and Telecommunications.Chongqing 400065 China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials-Hubei Key Laboratory of Ferro&Piezoelectric Materials and Devices Faculty of Physical and Electronic SciencesHubei UniversityWuhan 430062China College of Physics Chongqing UniversityChongqing 401331China

Recent research shows that increasing the carrier density after orbital alignment in AZn_(2)Sb_(2) (A=Ca,Yb,Eu,Sr,Mg)Zintl compounds yields remarkable results with regard to enhanced thermoelectric ***,research on carrier density increase via doping in these compounds is *** this study,we introduced Cu into the Zn sites in YbZn_(2)Sb_(2) and examined the thermoelectric properties.

关键词： properties doping performance

Rational design of robust and transparent superrepellent surfaces for long-term marine antifouling

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Science China(Technological Sciences) 2024年第7期67卷 2031-2039页

作者： CHEN hui WANG Zhi WANG DaHeng xiao Feng FU guang-En BU XueLing ZHAO Lei ZHANG Tao WU DaHeng PU JiBin The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science&TechnologyWuhan 430081China Key Laboratory of Advanced Marine Materials Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China

Superhydrophobic surfaces have demonstrated exceptional efficacy in combatting biofouling contaminations of optical devices and equipment in marine applications. However, the fabrication of highly transparent superhydrophobic materials remains a formidable challenge due to the inherent trade-off between surface roughness for superhydrophobicity and optical ***, we design a robust and transparent superhydrophobic coating(Si-POSS) embedded silica nanoparticles(200 nm) with fluorinated polyhedral oligomeric silsesquioxanes(F-POSS) and zinc pyrithione(ZPT). The Si-POSS coating exhibits excellent water repellence toward diverse liquids and optical transmittance exceeding 90% in the visible spectrum. Moreover, the Si-POSS coating sustains long-term anti-bacterial(> 99.11%) and anti-algal effects for over 30 days, accompanied by mechanical,chemical, and thermal stability. This research asserts that the Si-POSS coating with outstanding combined characteristics holds significant potential for marine applications, particularly in self-cleaning and antifouling endeavors.

关键词： superhydrophobic surface transparent marine antifouling nanoparticles

An Improved Fixed-point Algorithm for Independent Component Analysis of Functional MRI Data

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Chinese Journal of Biomedical Engineering(English Edition) 2009年第2期18卷 78-83页

作者： WENG xiao-guang WANG hui-nan QIAN Zhi-yu College of Automation Engineering Nanjing University of Aeronautics ＆ Astronautics Nanjing 210016 China

The fixed-point algorithm and infomax algorithm are two of the most popular algorithms in independent component analysis(ICA).However,it is hard to take both stability and speed into consideration in processing functional magnetic resonance imaging(fMRI)*** this paper,an optimization model for ICA is presented and an improved fixed-point algorithm based on the model is *** the new algorithms a small step size is added to increase the *** order to accelerate the convergence,an improvement on Newton method is made,which makes cubic convergence for the new *** the algorithm and two other algorithms to invivo fMRI data,the results show that the new algorithm separates independent components stably,which has faster convergence speed and less computation than the other two *** algorithm has obvious advantage in processing fMRI signal with huge data.

关键词： independent component analysis(ICA) functional magnetic reasonance imaging(fMRI) Newton iteration