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| 1 | Temperature field model in surface grinding: a comparative assessment显示文摘Grinding is a crucial process in machining workpieces because it plays a vital role in achieving the desired precision and surface quality.However,a significant technical challenge in grinding is the potential increase in temperature due to high specific energy,which can lead to surface thermal damage.Therefore,ensuring control over the surface integrity of workpieces during grinding becomes a critical concern.This necessitates the development of temperature field models that consider various parameters,such as workpiece materials,grinding wheels,grinding parameters,cooling methods,and media,to guide industrial production.This study thoroughly analyzes and summarizes grinding temperature field models.First,the theory of the grinding temperature field is investigated,classifying it into traditional models based on a continuous belt heat source and those based on a discrete heat source,depending on whether the heat source is uniform and continuous.Through this examination,a more accurate grinding temperature model that closely aligns with practical grinding conditions is derived.Subsequently,various grinding thermal models are summarized,including models for the heat source distribution,energy distribution proportional coefficient,and convective heat transfer coefficient.Through comprehensive research,the most widely recognized,utilized,and accurate model for each category is identified.The application of these grinding thermal models is reviewed,shedding light on the governing laws that dictate the influence of the heat source distribution,heat distribution,and convective heat transfer in the grinding arc zone on the grinding temperature field.Finally,considering the current issues in the field of grinding temperature,potential future research directions are proposed.The aim of this study is to provide theoretical guidance and technical support for predicting workpiece temperature and improving surface integrity. | Min Yang Ming Kong Changhe Li Yunze Long Yanbin Zhang Shubham Sharma Runze Li Teng Gao Mingzheng Liu Xin Cui Xiaoming Wang Xiao Ma Yuying Yang | 2023 | International Journal of Extreme Manufacturing2023，5，4： | 1 |
| 2 | Homotypic clustering of L1 and B1/Alu repeats compartmentalizes the 3D genome显示文摘Organization of the genome into euchromatin and heterochromatin appears to be evolutionarily conserved and relatively stable during lineage differentiation.In an effort to unravel the basic principle underlying genome folding,here we focus on the genome itself and report a fundamental role for L1(LINE1 or LINE-1)and B1/Alu retrotransposons,the most abundant subclasses of repetitive sequences,in chromatin compartmentalization.We find that homotypic clustering of L1 and B1/Alu demarcates the genome into grossly exclusive domains,and characterizes and predicts Hi-C compartments.Spatial segregation of L1-rich sequences in the nuclear and nucleolar peripheries and B1/Alu-rich sequences in the nuclear interior is conserved in mouse and human cells and occurs dynamically during the cell cycle.In addition,de novo establishment of L1 and B1 nuclear segregation is coincident with the formation of higher-order chromatin structures during early embryogenesis and appears to be critically regulated by L1 and B1 transcripts.Importantly,depletion of L1 transcripts in embryonic stem cells drastically weakens homotypic repeat contacts and compartmental strength,and disrupts the nuclear segregation of L1-or B1-rich chromosomal sequences at genome-wide and individual sites.Mechanistically,nuclear co-localization and liquid droplet formation of L1 repeat DNA and RNA with heterochromatin protein HP1αsuggest a phase-separation mechanism by which L1 promotes heterochromatin compartmentalization.Taken together,we propose a genetically encoded model in which L1 and B1/Alu repeats blueprint chromatin macrostructure.Our model explains the robustness of genome folding into a common conserved core,on which dynamic gene regulation is overlaid across cells. | J.Yuyang Lu Lei Chang Tong Li Ting Wang Yafei Yin Ge Zhan Xue Han Ke Zhang Yibing Tao Michelle Percharde Liang Wang Qi Peng Pixi Yan Hui Zhang Xianju Bi Wen Shao Yantao Hong Zhongyang Wu Runze Ma Peizhe Wang Wenzhi Li Jing Zhang Zai Chang Yingping Hou Bing Zhu Miguel Ramalho-Santos Pilong Li Wei Xie Jie Na Yujie Sun Xiaohua Shen | 2021 | Cell Research2021，31，6： | 1 |
| 3 | Design,Fabrication and Assembly of the Solar Upper Transition Region Imager(SUTRI)显示文摘The Solar Upper Transition Region Imager(SUTRI)focuses on the solar transition region to achieve dynamic imaging observation of the upper transition region.In this paper,we report the optical system design,mechanical design,ultrasmooth mirror manufacture and measurement,EUV multilayer film coating,prelaunch installation and calibration for the SUTRI payload at IPOE,Tongji University.Finally,the SUTRI carried by the SATech-01 satellite was successfully set to launch.All functions of this telescope were normal,and the observation results obtained in orbit were consistent with the design. | Zhanshan Wang Jun Yu Runze Qi Chunling He Zhengxiang Shen Li Jiang Weichen Gu Jiali Wu Zhe Zhang Pengfeng Sheng Yifan Wang Yue Yu Zeyi Ye JingJing Xia Yujie Xing Hongfei Jiao Bin Ma Qiushi Huang Zhong Zhang Xianyong Bai Yuanyong Deng Hui Tian Nange Wang Lun Shen Song Guo Lei Jing Xiaobo Chen Yang Gao Xiaocheng Zhu Xiaofeng Zhang Junwang He Qi Shi Shuo Liu Xingzi Bi | 2023 | Research in Astronomy and Astrophysics2023，23，9： | 0 |
| 4 | Petroleum geology and sub-source hydrocarbon accumulation of Permian reservoirs in Jinan Sag,eastern Junggar Basin,NW China显示文摘According to the latest drilling and the analysis of the burial history,source rock evolution history and hydrocarbon accumulation history,the sub-source hydrocarbon accumulation characteristics of the Permian reservoirs in the Jinan Sag,eastern Junggar Basin,are clarified,and the hydrocarbon accumulation model of these reservoirs is established.The results are obtained in four aspects.First,the main body of the thick salified lake basin source rocks in the Lucaogou Formation has reached the mature stage with abundant resource base.Large-scale reservoirs are developed in the Jingjingzigou,Wutonggou and Lucaogou formations.Vertically,there are multiple sets of good regional seals,the source-reservoir-caprock assemblage is good,and there are three reservoir-forming assemblages:sub-source,intra-source and above-source.Second,dissolution,hydrocarbon charging and pore-preserving effect,and presence of chlorite film effectively increase the sub-source pore space.Oil charging is earlier than the time when the reservoir becomes densified,which improves the efficiency of hydrocarbon accumulation.Third,buoyancy and source-reservoir pressure difference together constitute the driving force of oil charging,and the micro-faults within the formation give the advantage of'source-reservoir lateral docking'under the source rock.Microfractures can be critical channels for efficient seepage and continuous charging of oil in different periods.Fourth,the Jingjingzigou Formation experienced three periods of oil accumulation in the Middle-Late Permian,Middle-Late Jurassic and Late Neogene,with the characteristics of long-distance migration and accumulation in early stage,mixed charging and accumulation in middle stage and short-distance migration and high-position accumulation in late stage.The discovery and theoretical understanding of the Permian reservoirs in the Jinan Sag reveal that the thrust belt has good conditions for forming large reservoirs,and it is promising for exploration.The study results are of guidance and reference significance for oil and gas exploration in the Jinan Sag and other geologically similar areas. | LI Jianzhong CHEN Xuan YANG Runze LIN Tong YANG Fan MA Qiang GOU Hongguang WEI Yanzhao LIN Lin | 2023 | Petroleum Exploration and Development2023，50，3： | 0 |
| 5 | Thermodynamically controllable synthesis of ZIF-8 exposing different facets and their applications in single atom catalytic oxygen reduction reactions显示文摘The development of thermodynamically controllable synthetic strategy to manipulate the morphology of ZIF-8 without capping agent is essential to help understanding their facet effect and the structure-activity relationship of single atom catalysts derived from ZIF-8.Here,we prepared ZIF-8 with different morphologies(cube,truncated rhombododecahedral and rhombododecahedral)and thus area ratio of exposed{100},{110}facets by a thermodynamically controllable synthetic strategy.When the reaction proceeds under room temperature(30℃),the assembling of ZIF-8 followed an area-reducing layered growth mode,while switched to an integral layered growth mode at lower temperature-40℃.Moreover,this strategy also works to obtain ZIF-8 encapsulated with metal precursors(Fe(acac)_(3),Cu(acac)_(2)and Co(acac)_(2)).Single Fe atom anchored on nitrogen doped carbon catalysts(SA-Fe/CN)derived from Fe-ZIF-8 retain their original morphologies and the unsaturated surface-active sites on{100}facet,which further displays different catalytic performance towards oxygen reduction reaction(ORR).This work not only reveals the different growth pattern of ZIF-8,but also points out a new direction for designing and synthesizing MOFs with different morphology rationally. | Runze Ma Qiheng Li Jun Yan Yu Tao Shouyao Hu Donghao Liu Jiaxin Gong Yu Xiong | 2023 | Nano Research2023，16，7： | 0 |
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