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Two-dimensional interface superstructures assembled by well-ordered solute atoms

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Journal of Materials Science & Technology 2023年第11期142卷 253-259页

作者： peijun yang Shanshan Li Hongbo Xie Jianfeng Jin Chuangwei Liu Hucheng Pan Yuping Ren Weitao Jia Yaping Zong Gaowu Qin Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China School of Mechanical and Power Engineering Shenyang University of Chemical TechnologyShenyang 110142China College of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China

Segregation of solutes/impurities in the interfaces plays a decisive role in material performances.However,the segregation of solutes/impurities remains elusive due to the diversity of interfacial structures.Here,in a Mg-Nd-Mn ternary model system,two ordered novel two-dimensional(2D)interfacial superstructures formed by periodic segregation of solute atoms in special symmetric and asymmetric tilt grain boundaries(GBs)have been systematically investigated.Z-Contrast high-angle annular dark-field scanning transmission electron microscopy(HAADF-STEM)observations provided the atomic-level details on how solute atoms were arranged on these special partially coherent tilt GBs.The strained conditions of each atomic site at the tilt GBs were accurately reproduced by molecular dynamics(MD)simulations plus Voronoi analysis,and the rationality of solute segregation in each atomic-site was evaluated carefully based on the first-principles calculations.These findings expand our knowledge of solute/impurity segregation behaviors in the interfaces,especially the co-segregation behaviors in multi-component materials.

关键词： Magnesium alloy Interfacial segregation Molecular dynamics First-principles HAADF-STEM

Simple Colorless Long-Reach WDM-PON with Rayleigh Backscattering Noise Mitigation Employing Remodulated Orthogonal Coding

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China Communications 2017年第4期14卷 120-126页

作者： Zhisheng Li Qiang Dou Lei Wang peijun yang Chaobing Zhou School of Computer Science National University of Defense Technology

We propose and experimentally demonstrate a novel colorless full-duplex passive optical network architecture with Rayleigh backscattering optical beat interference(OBI) noise mitigation by using orthogonal codes. A pair of orthogonal codes are generated and transmitted from optical line terminal(OLT) to optical network unit(ONU) with the same wavelength, in which, one for downstream signal coding, and the other for the upstream seeding signal. In ONU, the upstream signal is remodulated without erasing the downstream signal. Extra centralized CW light sources and gain-saturation RSOAs are not needed. By using orthogonal codes, the spectral overlap between upstream and downstream signal is reduced, which can mitigate OBI noise significantly. The performance of transmission and power margin are investigated through experiments at different data rates, transmission distances compared with normal on-off keying(OOK) signals. The remodulated upstream signals are correlatively received at OLT with coding gain which is useful in long-reach transmissions. Due to coding gain and OBI noise mitigation, total 4～9d B power margin is achieved for 5Gb/s downstream and 1.25Gb/s upstream with 20 km to 70 km transmission distances.

关键词： colorless full-duplex passive optical obi orthogonal codes spectral overlap

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智能调节炉顶上密封阀夹紧力系统设计

冶金动力 2024年第1期 61-64页

作者：吴志勇杨培俊马鞍山钢铁股份有限公司安徽马鞍山243000

介绍了一种无料钟炉顶上密封阀夹紧力智能控制系统。通过在炉顶称量罐上安装压力变送器,在均压过程中实时检测均压气体压力,计算均压气体对上密封阀板的盲板力,并在液压系统中设置比例减压阀,建立均压气体压力与液压系统压力之间的比例... 详细信息

介绍了一种无料钟炉顶上密封阀夹紧力智能控制系统。通过在炉顶称量罐上安装压力变送器,在均压过程中实时检测均压气体压力,计算均压气体对上密封阀板的盲板力,并在液压系统中设置比例减压阀,建立均压气体压力与液压系统压力之间的比例平衡关系,通过计算机系统智能动态调节上密封阀液压系统的压力,降低并均衡上密封阀板与阀座之间的夹紧力,延长上密封阀板、阀座及上密封阀夹紧机构的使用寿命,降低无料钟炉顶上密封阀的故障率,从而保障了高炉炉顶设备运行的高效性。

关键词：无料钟炉顶上密封阀比例减压阀高炉

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乙烯聚合催化剂发展综述报告

广东化工 2024年第9期51卷 76-79+118页

作者：朱建华史青林傅蒙朱贤东杨培俊公园管道(安徽)有限公司安徽工程大学安徽师范大学

聚乙烯具有质轻、无味、无毒、优异的耐湿性和耐热性等性能，广泛应用于注塑、管材、板材、薄膜类等制品。聚乙烯材料高性能新产品的开发高度依赖于乙烯聚合新型催化剂的研发，故乙烯聚合催化剂的设计一直是国内外研究的热点。本文综述... 详细信息

聚乙烯具有质轻、无味、无毒、优异的耐湿性和耐热性等性能，广泛应用于注塑、管材、板材、薄膜类等制品。聚乙烯材料高性能新产品的开发高度依赖于乙烯聚合新型催化剂的研发，故乙烯聚合催化剂的设计一直是国内外研究的热点。本文综述了不同时期聚乙烯催化剂的研究进展，主要从铬基、Ziegler-Natta、茂金属、非茂金属和复合金属催化剂五个方面展开论述。

关键词：聚乙烯催化剂高性能茂金属开发

Factors contributing to the oxygen concentration over the Qinghai-Tibetan Plateau and its contribution rate calculation

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Science China Earth Sciences 2024年第2期67卷 497-509页

作者： peijun SHI Ying ZHANG Yanqiang CHEN Wenquan ZHU Xiaokang HU Heyi yang Lu JIANG Yonggui MA Haiping TANG State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing100875China Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing100875China The Institute for Disaster Management and Reconstruction Sichuan UniversityChengdu610065China Academy of Plateau Science and Sustainability People’s Government of Qinghai Province&Beijing Normal UniversityXining810016China

A decline in atmospheric oxygen concentration is projected in the 21st century given the background of global warming.The Qinghai-Tibetan Plateau is located at a high altitude,and thus,it faces a hypoxia challenge;however,knowledge of the factors contributing to its atmospheric oxygen concentration is still lacking.Here,we conducted joint observations of ecosystem oxygen production and carbon sinks and near-surface atmospheric oxygen concentrations on the Qinghai-Tibetan Plateau and meteorological elements at Beijing Fangshan Station.Using seasonal differences and statistical methods,we calculated the relative contribution rates of vegetation to changes in atmospheric oxygen concentration.Our results indicate that solar radiation,atmospheric humidity,and ecosystem oxygen consumption and production have a significant impact on the atmospheric oxygen concentration,and the impact shows temporal and spatial differences.Vegetation significantly impacts the oxygen concentration,with a contribution rate of 16.7%–24.5%,which is underestimated in existing research.Our findings provide important insights into the factors that influence atmospheric oxygen concentration and highlight the contribution of vegetation.To better understand the oxygen dynamics of the Qinghai-Tibetan Plateau,we recommend further field observations of soil respiration and vegetation photosynthesis to clarify the contributions of carbon storage,carbon sinks and other factors to the near-surface atmospheric oxygen concentration.

关键词： Qinghai-Tibetan Plateau Oxygen concentration Relative contribution rate Air temperature Vegetation

直径≤2 cm单发肝癌接受肝切除术和射频消融术的预后比较

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中国医刊 2024年第5期59卷 529-533页

作者：谭海东刘立国韩东冬刘笑雷司爽周瑞泉杨世伟杨佩军刘天同中日友好医院肝胆胰外科二部(肝移植科) 北京100029

目的比较直径≤2 cm的单发肝癌患者接受肝切除术和射频消融术后的生存差异。方法回顾性分析2004—2015年美国SEER数据库中直径≤2 cm的单发肝癌病例,患者均接受了肝切除术或射频消融术治疗,通过倾向性评分匹配筛选病例,分析两组患者... 详细信息

目的比较直径≤2 cm的单发肝癌患者接受肝切除术和射频消融术后的生存差异。方法回顾性分析2004—2015年美国SEER数据库中直径≤2 cm的单发肝癌病例,患者均接受了肝切除术或射频消融术治疗,通过倾向性评分匹配筛选病例,分析两组患者的生存情况。结果经倾向性评分匹配,纳入射频消融组216例,肝切除术组216例,两组临床特征基本一致。生存分析显示射频消融组5年癌症相关生存率为57.2%,明显低于肝切除术组的72.8%,差异有统计学意义(χ~2=7.135,P=0.008);射频消融组5年总生存率为47.6%,明显低于肝切除术组的64.5%,差异有统计学意义(χ~2=8.822,P=0.003)。多因素分析结果显示,射频消融术、单身状态是影响单发肝癌患者相关生存率和总生存率的独立危险因素(P<0.05),年龄是影响总生存率的独立危险因素(P<0.05)。结论对于直径≤2 cm的单发肝癌患者,相较于射频消融术,肝切除术在癌症相关生存率和总生存率方面更具优势。

关键词：肝癌单发预后肝切除术射频消融术

Microbiota in colorectal cancer related to liver metastasis

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Chinese Journal of Cancer Research 2024年第1期36卷 17-24页

作者： peijun Wei Weiming Han Zitong Zhang Xue Tian Chen yang Qiaoxuan Wang Weihao Xie Ying Liu Yuanhong Gao Hui Chang Department of Radiation Oncology State Key Laboratory of Oncology in South ChinaGuangzhou 510060China Guangdong Provincial Clinical Research Center for Cancer Guangzhou 510060China Sun Yat-sen University Cancer Center Guangzhou 510060China Department of Pediatric Oncology State Key Laboratory of Oncology in South ChinaGuangzhou 510060China

The prevalence of colorectal cancer(CRC) is increasing annually and metastasis is the principal cause of death in patients with CRC, with the liver being the most frequently affected site. Many studies have shown a strong interplay between the gut flora, particularly Fusobacterium nucleatum(F. nucleatum), Escherichia coli, and Bacteroides fragilis, and the development of gut tumors. Some strains can induce gut inflammation and produce toxins that directly harm gut epithelial cells, ultimately accelerating the onset and progression of CRC. However,little clinical evidence exists on the specific interplay between the gut microflora and colorectal cancer liver metastasis(CRLM). Some research showed the existence of viable F. nucleatum in distant metastasis of CRC.Subsequently, gut microbiota products, such as lipopolysaccharides, sodium butyrate, and protein cathepsin K, were also found to affect the development of CRC. This article summarizes the mechanism and research status of the interplay between gut microflora and CRLM, discusses the importance of gut microflora in the treatment of CRLM, and proposes a new approach to understanding the mechanism of CRLM and potential treatments for the microbiome. It is anticipated that the gut microbiota will be a formidable therapeutic and prophylactic tool for treating and preventing CRLM.

关键词： Gut microbiota liver metastasis colorectal cancer

基于卷积神经网络的钢轨螺孔裂纹识别算法研究

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铁道学报 2023年第4期45卷 111-116页

作者：杨崎李立波吴先梅杨培俊中国科学院声学研究所声场声信息国家重点实验室北京100190 中国科学院大学北京100049 中国铁路北京局集团有限公司北京100860 北京新科启源科技有限公司北京100176

钢轨由于长时间负载会出现各种伤损,对铁路运输安全造成威胁。螺孔裂纹是钢轨接头处的主要伤损,如果不及时发现很容易造成安全事故。已有钢轨伤损检测方法是使用超声波检测,人工回放检测数据进行伤损判别,该方法效率较低。基于机器学习... 详细信息

钢轨由于长时间负载会出现各种伤损,对铁路运输安全造成威胁。螺孔裂纹是钢轨接头处的主要伤损,如果不及时发现很容易造成安全事故。已有钢轨伤损检测方法是使用超声波检测,人工回放检测数据进行伤损判别,该方法效率较低。基于机器学习的伤损判别方法提高了钢轨伤损判别效率,但准确率不高。因此,针对该类钢轨伤损,利用卷积神经网络(CNN)与多层感知机(MLP)结合的模型,将螺孔超声波B扫图像作为识别对象,识别钢轨螺孔是否存在裂纹,提升螺孔裂纹的判别效率和准确率。经过数据集训练,在测试集上该模型的识别准确率达96.25%,在测试数据集以外的图像上进行应用,取得了很好的识别效果,证明该模型在钢轨螺孔裂纹识别问题上的可行性和模型的实用性。

关键词：螺孔螺孔裂纹 B扫图像卷积神经网络多层感知机

A case report of chylous ascites after cardiac surgery

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Emergency and Critical Care Medicine 2024年第1期4卷 42-45页

作者： Shuaishuai Yuan Pailing Xie Xiantao Liu peijun Li The University of Hong Kong-Shenzhen Hospital Cardiovascular Medicine Center Cardiac Intensive Care Unit ShenzhenGuangdongChina.

Background:Chylous ascites(CA),an emulsion rich in triglycerides,is a rare type of ascites,especially after cardiac surgery.Also,there are few reports of the occurrence of CA after mitral valve replacement,aortic valve replacement,tricuspid valvuloplasty,and coronary artery bypass grafting.Case presentation:We report the case of a 53-year-old man who underwent surgery for a diagnosis of mitral incompetence,aortic incompetence,tricuspid incompetence,and coronary atherosclerotic heart disease.Fifteen days after surgery,3000 mL of milky-yellow ascites appeared in the abdominal cavity,diagnosed as CA by laboratory examination.The ascites gradually disappeared after being drained,and the patients improved.The curative was objective,but the exact cause is not clear.Conclusion:Although CA is rare,it may occur during the surgical intervention in cardiac surgery.

关键词： Cardiac intensive care unit Cardiac valve replacement Case report Chylous ascites Coronary artery bypass graft Department of cardiac surgery