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Effects of Cerium-Rich Rare Earth and Al-Ti-B Composite Addition on Microstructure and Mechanical Properties of AlMg-Si Alloys

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稀有金属材料与工程 2025年第1期54卷 50-61页

作者： Chong Yufan Du Zhaoxin gong Tianhao Sun Baoan Pan Zheru Qi Lele Xie chengcheng cheng Jun School of Materials Science and Engineering Inner Mongolia University of TechnologyHohhot 010051China Institute of Physics Chinese Academy of SciencesBeijing 100190China Northwest Institute for Nonferrous Metal Research Xi'an 710016China

Modification of 6061 aluminum alloy was conducted through composite addition of cerium-rich rare earths and *** show that the composite addition of Al-Ti-B and Ce/La element at a specific ratio notably promotes the refinement of the alloy's *** and La elements are combined with Si and other elements to form rare earth phases,improving the morphology and distribution of precipitates and mitigating the adverse effects ofβ-Fe phases on the microstructure and mechanical properties of ***,excessive rare earth content poses challenges;it not only leads to a decrease in Mg-Si strengthening phase by binding with Si but also promotes the formation of larger or numerous rare earth phases that may act as initiation points for cracks,thereby impeding the improvement of the structure and performance of *** composite addition of cerium-rich rare earths and Al-Ti-B not only preserves the strength of the alloy but also significantly enhances the plasticity of the 6061 as-cast *** a composite addition ratio of Al-Ti-B:RE=2:1,the newly developed 6061-RE aluminum alloy exhibits increased average elongation by 50%and 45%in its as-cast and homogenized states,respectively,compared to the baseline 6061 alloy,facilitating subsequent deformation *** solution treatment at 540℃for 1 h and aging at 180℃for 5 h,the average ultimate tensile strength and yield strength of 6061-RE alloys reach 313.2 and 283.1 MPa,increased by 12.3%and 14.5%compared with those of the original alloy,respectively,and the average elongation is improved by 41%.

关键词： rare earth alloy Al-Mg-Si alloy cerium-rich rare earth mechanical property microstructure

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当前高校实验室安全教育软件现状分析及思考

电脑知识与技术（过刊） 2015年第11X期21卷 97-98页

作者：宋玉丹李庭古龚成龙淮海工学院设备与实验室管理处江苏连云港222000

实验室是高校培养人才和科学研究的必备场所,实验室安全关乎学生老师的生命及学校的财产,安全教育必不可少。该文对目前市场上几款主流实验室安全教育软件进行了调研对比,分析评价了各产品的优缺点,并提出了一些见解及建议。

关键词：实验室安全教育考试系统软件分析

Spatiotemporal Variations in Climatic Factors,Catchment Characteristic Induced Runoff Changes with Multi-Time Scales across the Contiguous United States

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Journal of Earth Science 2025年第1期36卷 146-160页

作者： Xinglong gong Shuping Du Fengyu Li Yibo Ding School of Water Conservancy & Civil Engineering Northeast Agricultural University Yellow River Engineering Consulting Co. Ltd.

Previous works were mainly concentrated on long-term average runoff alterations, and extreme temperatures and watershed conditions are little analyzed. In this study, we collected gauged river flow and meteorological data time series from 1916 to 2015 and 1941 to 2015 across the contiguous United States(CONUS) for 188 catchments to investigate the temporal trends and spatial features of runoff changes at multi-time scales. We also analyzed the relationships between runoff changes and climatic factors. Median descriptive statistics and Budyko coupled climate elasticity methods were used to calculate runoff elasticity in each time scale. The original Mann-Kendall trend test was used to test their trend significance in four time-scale(11, 20, 40, and 60 a), respectively. The results show that the trend of runoff changes is more significant in high time scales; total changes are heterogeneous over CONUS. After the 1970s, increases of up to 27% decade-1 were mainly concentrated in the mid-northern regions. Maximum temperature and catchment characteristics are vital factors for runoff alteration; runoff changes are independent of rainfall, and wet regions tend to have lower changes. These findings could help develop better regional water resource planning and management.

关键词： catchment characteristics climate change slipping window runoff changes trend analysis runoff elasticity

Bacterial indole-3-propionic acid inhibits macrophage IL-1β production through targeting methionine metabolism

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Science China Life Sciences 2025年

作者： Ziyi Han Jian Fu Aiyan gong Wenkai Ren State Key Laboratory of Livestock and Poultry Breeding College of Animal Science South China Agricultural University Animal Disease-resistant Nutrition Key Laboratory of Sichuan Province Sichuan Agricultural University China Institute of Veterinary Drug Control

The gut microbiota plays key roles in host health by shaping the host immune responses through their metabolites, like indole derivatives from tryptophan. However, the direct role of these indole derivatives in macrophage fate decision and the underlying mechanism remains unknown. Here, we found that bacterial indole-3-propionic acid(IPA) downregulates interleukin-1beta(IL-1β) production in M1 macrophages through inhibition of nuclear factor-kappa B(NF-κB) signaling. Mechanistically, IPA binds specifically with methionine adenosyltransferase 2A(MAT2A) to promote S-adenosylmethionine(SAM) synthesis, which facilitates the DNA methylation of ubiquitin-specific peptidase 16(USP16, a deubiquitinase), and in turn promotes Toll-like receptor 4(TLR4) ubiquitination and NF-κB inhibition. Furthermore,IPA administration attenuates sepsis in mouse models induced by lipopolysaccharides(LPS), showcasing its potential as a microbial-derived adjunct in alleviating inflammation. Collectively, our findings reveal a newly found microbial metabolite-immune system regulatory pathway mediated by IPA.

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On-orbit attitude planning for Earth observation imaging with star-based geometric calibration

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Science China Technological Sciences 2025年第2期68卷 247-260页

作者： Di HUANG Zhifu WANG Jianya gong Haoran JI Institute of Aerospace Science and Technology School of Remote Sensing and Information Engineering Wuhan University State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing School of Remote Sensing and Information Engineering Wuhan University National Key Laboratory of Air-based Information Perception and Fusion Intelligent Game and Decision Laboratory

To improve the quality of remote sensing images, a novel on-orbit attitude planning method for Earth observation imaging with star-based geometric calibration is presented in this study. Unlike traditional imaging processes, the proposed method includes both pre-calibration and post-calibration stages to enhance the accuracy of satellite geometric positioning. A multiple-constraint attitude planning algorithm was developed to ensure star-based calibration, wherein the satellite camera and star sensors simultaneously capture the images of stars. This integration of cameras and multiple star sensors enables effective attitude determination. During the Earth imaging stage, a fast on-orbit attitude planning algorithm was developed to determine the satellite attitude and the optimal imaging times for ground targets. Compared with existing methods, the fast on-orbit attitude planning algorithm can significantly reduce computational time and resource consumption via initial value selection and *** demonstrate the effectiveness of the proposed attitude planning method, which was successfully applied to Wuhan 1 satellite.

关键词： attitude planning Earth observation imaging geometric calibration attitude constraints

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Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期7卷 152-160页

作者： Zhi-Jun Xie Jia-Lin Li Ling gong Xiang-Li Zhong Hong-Jia Song Jin-Bin Wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词： Arc ion plating Multilayer structure sp3 bond Ta-C coating Wear resistance

Modulated synthesis of stoichiometric and sub-stoichiometric two-dimensional covalent organic frameworks for enhanced ethylene purification

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Chinese Chemical Letters 2025年第1期36卷 272-276页

作者： Jiahao Li Guinan Chen Chunhong Chen Yuanyuan Lou Zhihao Xing Tao Zhang chengtao gong Yongwu Peng College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014China State Key Laboratory of Organic Electronics and Information Displays&Jiangsu Key Laboratory for Biosensors Institute of Advanced Materials(IAM)Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)Nanjing University of Posts and TelecommunicationsNanjing 210023China

Controlled synthesis of two-dimensional covalent organic frameworks(2D COFs),including stoichiometric and sub-stoichiometric variations,is a topic of growing interest due to its potential in gas separation *** this study,we successfully synthesized three distinct 2D COFs by carefully adjusting solvent compositions and monomer ratios during the synthesis of[4+4]type *** included a stoichiometric[4+4]type COF and two sub-stoichiometric[4+2]type COFs,featuring unreacted amino or formyl *** resulting COFs exhibit different gas adsorption and separation ***,sub-stoichiometric COF-DA with residual amino groups shows comparable adsorption capacity for C_(2)H_(2),C_(2)H_(4),and CO_(2)to stoichiometric *** contrast,sub-stoichiometric COF-Py with residual formyl groups displays enhanced adsorption selectivity for C_(2)H_(2)/C_(2)H_(4)and C_(2)H_(2)/CO_(2)separation,with the C_(2)H_(2)/C_(2)H_(4)selectivity being the highest among reported COFs,attributed to increased pore polarity resulting from the presence of formyl *** study not only offers an additional example of substoichiometric COF synthesis but also advocates for further exploration of sub-stoichiometric COF materials,particularly in the field of gas adsorption and separation.

关键词： Two-dimensional covalent organic frameworks Stoichiometric and sub-stoichiometric Residual functional groups Ethylene purification

The low-latitude sodium layer:comparative data from lidar observations at Hainan,China and São Paulo,Brazil

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Earth and Planetary Physics 2025年第1期9卷 39-53页

作者： Fang Wu Jing Jiao GuoTao Yang LiFang Du ZhengKuan Liu HaoRan Zheng JiXin Guo ShaoHua gong YaJun Zhu State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Hainan National Field Science Observation and Research Observatory for Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China China-Brazil Joint Laboratory for Space Weather NSSC/INPESão Josédos Campos 12227-010Brazil School of Physics and Electronics Engineering Hainan Normal UniversityHaikou 571158China

Physical and chemical processes observed in the mesosphere and thermosphere above the Earth’s low latitudes are complex and highly interrelated to activity in the low-latitude *** sodium detected by lidar can yield clues to dynamic and chemical processes in these spatial layers above the Earth’s *** paper is based on sodium layer data collected at two low-latitude stations,one in the northern hemisphere and one in the *** low-latitude sodium layer exhibits conspicuous seasonal variations in shape,density,and altitude;these variations are similar between Earth’s hemispheres:sodium layer density at both stations reaches its seasonal maximum in autumn and minimum in ***,maximal Na density over Brazil is greater than that over *** variations of Na density above the two low-latitude stations are also similar;at both,maxima are observed before *** variations of the Na layer over Brazil that differ from those observed in the northern hemisphere may be related to the South Atlantic Magnetic Anomaly(SAMA)or fountain *** suggest that low-latitude Na layer data may provide useful additional evidence that could significantly improve the low-latitude part of the WACCM-Na model.

关键词： metallic sodium layer seasonal variation nocturnal variation lidar

Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2

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Neural Regeneration Research 2025年第6期20卷 1801-1815页

作者： Qing He Zhen Wang Yuchen Wang Mengjie Zhu Zhile Liang Kanghong Zhang Yuge Xu gong Chen GHM Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina

Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain.

关键词： aquaporin-4 Ascl1 astrocyte cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 reprogramming