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Wear Evaluation on Ni_3Al/MnS Composite Related to Metallurgical Processes

Journal of Iron and Steel Research International 2012年第7期19卷 46-54页

作者： karin gong LUO He-li ZHOU Zhi-feng TIAN Zhi-ling Lars Nyborg LI Chang-hai Department of Materials and Manufacturing Technology Chalmers University of Technology Gothenburg Se-412 96 Sweden China Iron and Steel Research Institute Group Beijing 100081 China Department of Manufacturing Engineering and Engineering Management City University of Hong Kong Hong Kong China

Iron alloyed Ni3Al with composition of Ni-18. 8Ab10. 7Fe-0. 5Mn-0. 5Ti-0. 2B in atom percent （NAC alloy） showed attractive tribological properties under unlubrication condition at room temperature. The alloy was prepared by hot isostatic pressing （HIP） process. The wear properties were associated with its intrinsic deformation mechanism. Unfortunately, the single phase NAC-alloy worked inadequately with its counterpart disk, and also showed a poor machinability. In the present work, NAC-alloy matrix composite with 6 % （volume percent） MnS particle addi- tion was studied to improve its wear behaviors and performance on machining. Two metallurgical processes of HIP and vacuum casting were applied to produce the testing materials. Pin-on-disk （POD） measurements were carried out at room temperature. A commercial vermicular graphite cast iron was selected as a reference material. The counter- part disk was made of a grey cast iron as liner material in ship engines. The contact pressures of 2.83 MPa and 5.66 MPa were normally applied in the tests. The investigation indicated that MnS particle addition in the NAC-alloy composites functions as an effective solid lubricant, and improved wear properties and machinability of the materials. Obvi- ously, as-cast NAC-alloy with in-situ formed MnS-phase was working more effectively with the counterpart, compa- ring to the HIPed NAC-alloy composite with MnS particles. At the high contact pressure of 5.66 MPa, the specific wear rate of the as-cast NAC-alloy composite was high. The phenomenon of the negative effect is mostly due to the brittle second NiAl phase as evidenced in the microstructure analysis.

关键词： HIP processing friction coefficient specific wear rate intermetallics sliding wear casting machinability

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碳化铬/Ni_3Al复合堆焊层组织及摩擦磨损分析

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焊接学报 2012年第2期33卷 101-104,118页

作者：安同邦 gong karin 骆合力彭云朱晓云田志凌钢铁研究总院北京100081 Chalmers University of Technology Se-412 96 Gothenburg Sweden 昆明理工大学材料科学与工程学院昆明650093

采用光学显微镜、扫描电镜、电子探针及X射线衍射分析钨极氩弧堆焊碳化铬增强Ni3Al基复合堆焊层的组织结构,并采用销盘式干摩擦磨损试验机对堆焊层与活塞环用蠕墨铸铁材料的干摩擦磨损性能进行试验比较.结果表明,复合堆焊层内形成Ni3Al... 详细信息

采用光学显微镜、扫描电镜、电子探针及X射线衍射分析钨极氩弧堆焊碳化铬增强Ni3Al基复合堆焊层的组织结构,并采用销盘式干摩擦磨损试验机对堆焊层与活塞环用蠕墨铸铁材料的干摩擦磨损性能进行试验比较.结果表明,复合堆焊层内形成Ni3Al金属间化合物基体,其中弥散分布有大量细小的块状和条状碳化物硬质相Cr3C2和Cr7C3;焊接时焊丝中Cr3C2颗粒溶解析出,重新析出的碳化铬颗粒中包含Fe和Ni元素,碳化铬颗粒与Ni3Al基体形成良好的冶金结合;弥散分布的碳化铬颗粒和Ni3Al基体固溶强化的Cr元素决定了堆焊层具有较高的硬度.室温条件下,复合堆焊层具有优异的耐干摩擦磨损性能,其摩擦系数为0.23,远低于活塞环蠕墨铸铁的0.39;磨损率仅为蠕墨铸铁材料的43%.

关键词：碳化铬 Ni3Al基体堆焊摩擦系数耐磨性

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送粉速率对Ni_(3)Al基合金激光熔覆组织与耐磨性能的影响

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粉末冶金工业 2023年第2期33卷 33-37页

作者：邢德远韩伟 karin gong 李长海赵琳田志凌钢铁研究总院有限公司北京100081 查尔姆斯理工大学哥德堡SE-41296

采用激光熔覆在45钢表面制备Ni_(3)Al基合金熔覆层,利用扫描电镜、X射线衍射仪和摩擦磨损试验机,研究了送粉速率对Ni_(3)Al基合金激光熔覆层组织特征与耐磨性能的影响。结果表明,Ni_(3)Al基合金熔覆层组织主要为Ni_(3)Al和细小弥散分布... 详细信息

采用激光熔覆在45钢表面制备Ni_(3)Al基合金熔覆层,利用扫描电镜、X射线衍射仪和摩擦磨损试验机,研究了送粉速率对Ni_(3)Al基合金激光熔覆层组织特征与耐磨性能的影响。结果表明,Ni_(3)Al基合金熔覆层组织主要为Ni_(3)Al和细小弥散分布的原位自生M_(7)C_(3);送粉速率增至1.45 kg/h时,熔覆层出现粗大的Cr_(3)C_(2)。随着送粉速率增加,Ni_(3)Al基合金熔覆层耐磨性能显著提高,远优于蠕墨铸铁耐磨性能。其中,送粉速率为1.16 kg/h时,Ni_(3)Al基合金熔覆层磨损率为0.74×10^(-5)mm^(3)/(N·m),而且其对磨材料磨损较小,分别为蠕墨铸铁及其对磨材料磨损率的19.6%和67.7%。

关键词： Ni_(3)Al基合金激光熔覆送粉速率显微组织磨损性能

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Cr_(3)C_(2)含量对Ni_(3)Al基合金激光熔覆层组织与性能的影响

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稀有金属材料与工程 2024年第10期53卷 2852-2859页

作者：阚成玲彭云龚侠李长海赵琳田志凌钢铁研究总院有限公司焊接研究所北京100081 查尔姆斯理工大学瑞典哥德堡SE-41296

本工作借助激光熔覆技术,在45钢上开展不同Cr_(3)C_(2)添加量的Ni_(3)Al+Cr_(3)C_(2)混合粉末制备Ni_(3)Al基合金激光熔覆层试验研究,利用扫描电镜、X射线衍射仪、透射电镜及摩擦磨损试验机等设备,统计不同Cr_(3)C_(2)添加量下原位自生... 详细信息

本工作借助激光熔覆技术,在45钢上开展不同Cr_(3)C_(2)添加量的Ni_(3)Al+Cr_(3)C_(2)混合粉末制备Ni_(3)Al基合金激光熔覆层试验研究,利用扫描电镜、X射线衍射仪、透射电镜及摩擦磨损试验机等设备,统计不同Cr_(3)C_(2)添加量下原位自生碳化物的含量及尺寸,分析碳化物对Ni_(3)Al基合金熔覆层显微组织、显微硬度及摩擦磨损性能的影响。结果表明:Ni_(3)Al基合金激光熔覆层组织主要为Ni_(3)Al基相和原位自生的Cr_(7)C_(3)碳化物。随着Cr_(3)C_(2)含量的增加,熔覆层原位自生碳化物含量由6.8%增加至32.3%,平均尺寸由0.10μm增长至0.78μm,熔覆层显微硬度(HV)由4615.8 MPa提高至5968.2 MPa。当Cr_(3)C_(2)含量为35%时,碳化物呈小颗粒弥散分布,摩擦磨损过程中产生均匀磨损,使熔覆层磨损量低至0.19 mg,此时对磨盘的磨损量相对最低,约为1.23 mg;而当Cr_(3)C_(2)含量为45%时,碳化物含量虽然达到32.3%,但多以大尺寸颗粒为主,在摩擦磨损过程中大颗粒碳化物发生断裂剥落,加速了对磨盘的磨损。

关键词： Ni_(3)Al基合金激光熔覆原位自生碳化物显微组织耐磨性能

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Potassium and calcium channels in different nerve cells act as therapeutic targets in neurological disorders

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Neural Regeneration Research 2025年第5期20卷 1258-1276页

作者： Qing Qiu Mengting Yang Danfeng gong Haiying Liang Tingting Chen Department of Pharmacology School of PharmacyNantong UniversityNantongJiangsu ProvinceChina Jiangsu Province Key Laboratory of Inflammation and Molecular Drug Target NantongJiangsu ProvinceChina Department of Pharmacy Longyan First Affiliated Hospital of Fujian Medical UniversityLongyanFujian ProvinceChina

The central nervous system, information integration center of the body, is mainly composed of neurons and glial cells. The neuron is one of the most basic and important structural and functional units of the central nervous system, with sensory stimulation and excitation conduction functions. Astrocytes and microglia belong to the glial cell family, which is the main source of cytokines and represents the main defense system of the central nervous system. Nerve cells undergo neurotransmission or gliotransmission, which regulates neuronal activity via the ion channels, receptors, or transporters expressed on nerve cell membranes. Ion channels, composed of large transmembrane proteins, play crucial roles in maintaining nerve cell homeostasis. These channels are also important for control of the membrane potential and in the secretion of neurotransmitters. A variety of cellular functions and life activities, including functional regulation of the central nervous system, the generation and conduction of nerve excitation, the occurrence of receptor potential, heart pulsation, smooth muscle peristalsis, skeletal muscle contraction, and hormone secretion, are closely related to ion channels associated with passive transmembrane transport. Two types of ion channels in the central nervous system, potassium channels and calcium channels, are closely related to various neurological disorders, including Alzheimer's disease, Parkinson's disease, and epilepsy. Accordingly, various drugs that can affect these ion channels have been explored deeply to provide new directions for the treatment of these neurological disorders. In this review, we focus on the functions of potassium and calcium ion channels in different nerve cells and their involvement in neurological disorders such as Parkinson's disease, Alzheimer's disease, depression, epilepsy, autism, and rare disorders. We also describe several clinical drugs that target potassium or calcium channels in nerve cells and could be u

关键词： astrocytes calcium channels central nervous system extracellular ion concentration microglia neurological disorders neurons potassium channels

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The Mechanism of Heating Rate on the Secondary Recrystallization Evolution in Grain Oriented Silicon Steel

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 275-282页

作者： GAO Qian LI Jun WANG Xianhui CAO Laifu gong Jian LI Bo Central Iron and Steel Research Institute Group Beijing 100081China Shougang Zhixin Electromagnetic Material R&D(Beijing)Co. Ltd.Beijing 101300China Beijing Shougang Co. Ltd.Qian’an 064404China

Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing,in which the evolution of magnetic properties,grain orientations and precipitates were *** illustrate the Zener factor,the diameter and number density of precipitates of interrupted testing samples were statistically *** effect of precipitate ripening on the Goss texture and magnetic property was *** indicated that the trend of Zener factor was similar under different heating rates,first increasing and then decreasing,and that the precipitate maturing was greatly inhibited as the heating rate *** recrystallization was developed at the temperature of 1010℃when a heating rate of 5℃/h was used,resulting in Goss,Brass and{110}oriented grains growing abnormally and a magnetic induction intensity of ***,increasing the heating rate to 20℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss ***,when the heating rate was extremely fast,such as 40℃/h,poor secondary recrystallization was developed with many island grains,corresponding to a decrease in magnetic induction intensity to 1.87 *** a suitable heating rate of 20℃/h,the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1020℃were found among the experimental variables in this *** heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates,leading to the deviation and dispersion of Goss texture,thereby reducing the magnetic properties.

关键词： high temperature annealing heating rate secondary recrystallization grain oriented silicon steel

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Engine Misfire Fault Detection Based on the Channel Attention Convolutional Model

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Computers, Materials & Continua 2025年第1期82卷 843-862页

作者： Feifei Yu Yongxian Huang Guoyan Chen Xiaoqing Yang Canyi Du Yongkang gong School of Mechatronic Engineering Guangdong Polytechnic Normal UniversityGuangzhou510665China School of Automotive and Transportation Engineering Guangdong Polytechnic Normal UniversityGuangzhou510665China

To accurately diagnosemisfire faults in automotive engines,we propose a Channel Attention Convolutional Model,specifically the Squeeze-and-Excitation Networks(SENET),for classifying engine vibration signals and precisely pinpointing misfire *** the experiment,we established a total of 11 distinct states,encompassing the engine’s normal state,single-cylinder misfire faults,and dual-cylinder misfire faults for different *** collection was facilitated by a highly sensitive acceleration signal collector with a high sampling rate of 20,*** collected data were methodically divided into training and testing sets based on different experimental groups to ensure generalization and prevent overlap between the two *** results revealed that,with a vibration acceleration sequence of 1000 time steps(approximately 50 ms)as input,the SENET model achieved a misfire fault detection accuracy of 99.8%.For comparison,we also trained and tested several commonly used models,including Long Short-Term Memory(LSTM),Transformer,and Multi-Scale Residual Networks(MSRESNET),yielding accuracy rates of 84%,79%,and 95%,*** underscores the superior accuracy of the SENET model in detecting engine misfire faults compared to other ***,the F1 scores for each type of recognition in the SENET model surpassed 0.98,outperforming the baseline *** analysis indicated that the misclassified samples in the LSTM and Transformer models’predictions were primarily due to intra-class misidentifications between single-cylinder and dual-cylinder misfire *** delve deeper,we conducted a visual analysis of the features extracted by the LSTM and SENET models using T-distributed Stochastic Neighbor Embedding(T-SNE)*** findings revealed that,in the LSTMmodel,data points of the same type tended to cluster together with significant ***,in the SENET model,data points of various types were more widely and evenly dispersed,demonstra

关键词： Channel attention SENET model engine misfire fault fault detection

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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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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

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Long-read sequencing reveals novel genetic polymorphisms in the major histocompatibility complex region and their impacts on the Han Chinese population

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Science China Life Sciences 2025年

作者： Cong Zhou Tingting gong Shuhang Li Li Jin Shaohua Fan State Key Laboratory of Genetic Engineering Lab for Evolutionary Synthesis School of Life Sciences Human Phenome Institute Fudan University Research Unit of Dissecting the Population Genetics and Developing New Technologies for Treatment and Prevention of Skin Phenotypes and Dermatological Diseases (2019RU058) Chinese Academy of Medical Sciences

Human leukocyte antigen(HLA) genes in the major histocompatibility complex(MHC) region are crucial for immunity and are associated with numerous diseases and phenotypes. The MHC region's complexity and high genetic diversity make it challenging to analyze using short-read sequencing(SRS) technology. We sequence the MHC region of 100 Han Chinese individuals using both long-read sequencing(LRS) and SRS platforms at approximately 30X coverage to study genetic alterations and their potential functional impacts. LRS provides significantly greater coverage of the MHC region and eight classical HLA genes, particularly at the HLA-DRB1 locus, compared with SRS. We detect 78,249 single nucleotide polymorphisms(SNPs) using LRS, with 26.0% undetectable by SRS. Based on SNP and inferred HLA allele types, we construct an LRS-based MHC reference panel for the Han Chinese, containing approximately 2.6 times more genetic variants than the SRS-based Han-MHC reference panel. A phenome-wide association study assessing 26,024 phenotypes across 15 categories identifies significant associations for 7,879 independent variants(including 809 LRS-specific SNPs) with 409 phenotypes in nine categories. This analysis reveals 24 unreported HLA allele associations in the bioelectric and cellular categories. The conditional analysis identifies 530independent signals across the 409 phenotypes, including 28 previously unreported signals of eight classical HLA genes associated with 33phenotypes. Of the top-associated SNPs, 191 are detected by LRS only. Fine-mapping identifies 126 independent candidate causal SNPs for three immune-related cellular phenotypes, with 17 detected exclusively by LRS. Our study reveals previously unreported variants and their functional impacts in the MHC region, enhancing our understanding of genetic diversity and its potential biological implications in the Han Chinese population.

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