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Research 2024年第1期2023卷 403-416页

作者： Yushan Geng Wenyuan Chen Hui Tan Jun Cheng shengyu zhu Jun Yang Weimin Liu State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000PR China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049PR China Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing Yantai 264000PR China

Sustained wear damages on the sliding surfaces of alloys are generally the culprit responsible for the failure of various mechanical systems.Inspired by high-entropy effects,here we deliberately deploy nanohierarchical architecture with composition undulation in a Ni50(AlNbTiV)_(50) complex concentrated alloy,which yields ultralow wear rate within the order of 10^(−7) to 10^(−6) mm^(3)/Nm between room temperature and 800℃.Such remarkable wear resistance heretofore represents one of the highest wear resistance reported for the bulk alloys or composites,and originates from the multi-type adaptive friction interface protection governed by intrinsically nano-coupled grains and nanoprecipitates.This cooperative heterostructure releases gradient frictional stress in stages upon wear at room temperature through the coexistence of multiple deformation pathways while activating a dense nanocrystalline glaze layer upon wear at 800℃ to minimize adhesive and oxidative wear.Our work uncovers a practical avenue for tailoring wear properties with multicomponent heterostructures over a wide temperature range.

关键词： wear alloys friction

A(CrFeNi)_(83)(AlTi)_(17) high-entropy alloy matrix solid-lubricating composite with exceptional tribological properties over a wide temperature range

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Journal of Materials Science & Technology 2023年第22期153卷 75-91页

作者： Yushan Geng Jun Cheng Hui Tan Qichun Sun Juanjuan Chen shengyu zhu Anh Kiet Tieu Jun Yang Weimin Liu State Key Laboratory of Solid Lubrication Chinese Academy of SciencesLanzhou Institute of Chemical PhysicsLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Shandong Laboratory of Yantai Advanced Materials and Green Manufacturing Yantai 264000China School of Mechanical MaterialsMechatronic and Biomedical EngineeringUniversity of WollongongWollongongNSW 2500Australia

High-entropy alloy matrix solid-lubricating composites(HSLCs)are promising anti-wear and friction-reduced materials to meet the demands of complicated engineering applications.Here we present a strat-egy to develop HSLCs by using the coupled high-entropy phases of(BCC+FCC+L2_(1))with near-equal volume fraction as the matrix material,instead of using the usual single phase-dominated high-entropy phases,which can preserve the intrinsic strength and deformability of the matrix while activating adap-tive wear protection during sliding.This enables a low coefficient of frictions of 0.23-0.31 and wear rates within the order of 10^(-6)-10^(-5) mm^(3) N m^(-1) for the(CrFeNi)_(83)(AlTi)_(17)-Ag-BaF_(2)/CaF_(2) HSLC between room-temperature and 800℃,considerably outperforming the reported HSLCs and conventional alloy matrix solid-lubricating composites.At low and moderate temperatures,the synergistic Ag-BaF_(2)/CaF_(2) lubricat-ing films eliminate the surface stress concentration upon wear,thus suppressing three-body abrasion and surface roughening during the groove multiplication process.At elevated temperatures,the high-entropy composite tribo-layers provide the friction interface with strong and deformable stress shielding,which avoids the oxidative and adhesive wear triggered by the delamination of the tribo-layer.Developing sim-ilar coupled high-entropy matrix phases may open an avenue for further optimization of the tribological properties of the HSLCs.

关键词： Solid-lubricating composites High-entropy alloys Wear mechanism High temperature Tribochemical reaction

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甲骨文所见医疾资料研究综论

医学与哲学 2024年第3期45卷 70-73页

作者：朱生玉高飞天津大学语言科学研究中心天津300350 北京中医药大学国学院北京102488

甲骨文中保存了目前所见最早的医疾资料,引起了古文字学家、历史学家、中医学者的共同关注,产生了非常丰富的研究成果。目前,关于甲骨文医疾资料的研究,主要集中在甲骨文医疾资料数量、病症名称、致病原因、诊疗方法等几个方面;以往研... 详细信息

甲骨文中保存了目前所见最早的医疾资料,引起了古文字学家、历史学家、中医学者的共同关注,产生了非常丰富的研究成果。目前,关于甲骨文医疾资料的研究,主要集中在甲骨文医疾资料数量、病症名称、致病原因、诊疗方法等几个方面;以往研究中存在释字不确、观点更新滞后、对卜辞语句理解欠准确、过度解读等问题,应引起学界的重视。甲骨文医疾资料的研究当以准确识文断字为前提,其研究具有跨学科性,古文字学、中医学等相关学科的交叉合作有助于推进甲骨文医疾资料的纵深研究。

关键词：甲骨文医疾资料疾病名称

Microstructure, mechanical and tribological properties of TiAl-based composites reinforced with high volume fraction of nearly network Ti_2AlC particulates

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Journal of Materials Science & Technology 2018年第4期34卷 670-678页

作者： Jun Cheng shengyu zhu Yuan Yu Jun Yang Weimin Liu State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of Sciencestanzhou 730000China

TiAl-based composites reinforced with different high volume fractions of nearly network TizAIC phase have been successfully prepared by mechanical alloying and hot-pressing method. Their microstructure. mechanical and tribological properties have been investigated. Ti2AIC network becomes continuous but the network wall grows thicker with increasing the Ti2AIC content. The continuity and wall size of the network Ti2AIC phase exert a significant influence on the mechanical properties. The bending strength of the composites first increases and then decreases with the Ti2A1C content. The compressive strength of the composite decreases slightly compared to the TiAI alloy, but the hardness is enhanced. Due to the high hardness and load-carrying capacity of the network structure, these composites have the better wear resistance. And this enhancement is more notable at low applied loads and high Ti2A1C content. The mechanisms simulating the role of network Ti2AIC phase on the wear behavior and the wear process of TiAl/Ti2AIC composites at different applied loads have been proposed.

关键词： TiAl/Ti2AIC composites Network structure Wear resistance

三苯胺功能化有序介孔聚合物作为无金属光催化剂用于二硫化物合成

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有机化学 2024年第2期44卷 605-612页

作者：刘继宇李圣玉陈款朱茵张元兰州大学化学化工学院功能有机分子化学国家重点实验室兰州730000

有机二硫化物广泛存在于活性天然产物及药物分子中,其在生物领域也有广泛的用途.可见光促进的两分子硫醇间的氧化偶联是制备对称二硫化物绿色、高效和原子经济的方法之一,但是此类反应所使用的光敏剂(金属配合物、有机小分子及无机半导... 详细信息

有机二硫化物广泛存在于活性天然产物及药物分子中,其在生物领域也有广泛的用途.可见光促进的两分子硫醇间的氧化偶联是制备对称二硫化物绿色、高效和原子经济的方法之一,但是此类反应所使用的光敏剂(金属配合物、有机小分子及无机半导体等)分别具有价格昂贵、光稳定性差、可见光吸收范围窄及易于被光腐蚀等问题.因此,开发价格便宜、稳定性好以及可回收的非金属光催化体系,降低大规模合成的成本依然是该领域亟需解决的问题.在此,报道了一种三苯胺功能化的有序介孔聚合物(TPA-MPs)作为非金属多相光催化剂催化的硫醇/硫酚需氧氧化偶联反应.该反应可在室温和空气氛围下高效合成多种二硫化物.TPA-MPs催化剂可重复使用6次以上而光催化活性无明显下降.开发的多相光催化体系具有操作简便、反应条件温和和绿色环保等优点,并且可以有效放大至克级规模,为有机二硫化物的合成提供了新颖高效的工具.

关键词：二硫化物光催化多相催化有序介孔聚合物

A novel Cu-doped high entropy alloy with excellent comprehensive performances for marine application

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Journal of Materials Science & Technology 2021年第10期69卷 48-59页

作者： Yuan Yu Nannan Xu shengyu zhu zhuhui Qjao Jianbin Zhang Jun Yang Weimin Liu State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Qingdao Center of Resource Chemistry and New Materials Qingdao 266000China School of Public Health Qingdao UniversityQingdao266000China

High entropy alloy(HEA)has attracted great interests as one of the promising multifunctional materials in marine applications.However,Cu as an effective biocide tends to form segregation in HEA,which could deteriorate corrosion and induce brittle fracture.Herein,we report a strategy to tailor the existing form of Cu in HEA from undesired large-scale segregation to uniform distribution with dispersed nanoscale precipitation,while retaining the unique structure characteristics of HEA.Eliminating Cu segregation improves toughness and avoids serious corrosion in the grain boundary.Uniform distribution with dispersed nanoscale precipitation of Cu further enhances the antifouling and lubricating abilities of Cu-doped HEA.Tailored AlCoCrFeNiCu_(0.5)HEA in this work has excellent comprehensive properties combining good mechanical properties,outstanding antifouling abilities,superior resistance to corrosion and wear.Furthermore,the corresponded mechanisms are discussed in terms of Cu-segregation-eliminated,nanoscale-Cu-precipitate-forming and comprehensive properties.

关键词： High entropy alloys Copper Nanoscale precipitate Comprehensive properties Ocean

Investigation of tribological characteristics of nickel alloybased solid-lubricating composites at elevated temperatures under vacuum

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Friction 2021年第5期9卷 990-1001页

作者： Jinming ZHEN Jun CHENG Hui TAN Qichun SUN shengyu zhu Jun YANG Weimin LIU College of Materials Science and Engineering Liaocheng UniversityLiaocheng 252059China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

The development of a high‐performance solid‐lubricating composite with excellent self‐lubricity over a broad temperature range in vacuum is significant to solve the frictional problems of spatial mechanisms.In this study,the vacuum tribological behaviors of nickel‐matrix/Ag/(Ca,Ba)F2/graphite(0–2 wt%)composites were studied from 25 to 800°C.The results show that the synergistic effects of solid lubricants can significantly improve the tribological properties of the composites in vacuum,with the graphite content contributing considerably.For 2 wt%graphite,a low friction coefficient(0.14–0.25)and the lowest wear rate((0.12–4.78)×10^(-5) mm^(3)∙N^(-1)∙m^(-1))were observed in vacuum over the entire testing temperature range.Moreover,the wear mechanisms were clarified via analysis of the chemical composition and morphologies of the sliding surfaces.

关键词： metal matrix composite graphite solid lubrication vacuum high temperature

单细胞RNA测序揭示维持性血液透析患者外周血免疫细胞的转录组特征

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肾脏病与透析肾移植杂志 2024年第2期33卷 127-135页

作者：董生玉朱杰夫师朗吴雄飞武汉大学人民医院肾内科武汉430060 武汉大学人民医院器官移植科武汉430060

目的:通过单细胞RNA测序(scRNA-seq)揭示维持性血液透析(MHD)患者的外周血单个核细胞(PBMC)的转录组特征及免疫状态。方法:使用scRNA-seq技术对MHD患者PBMC进行了研究,揭示其在相关疾病中的状态及分子特性的变化。采用无监督聚类和注释... 详细信息

目的:通过单细胞RNA测序(scRNA-seq)揭示维持性血液透析(MHD)患者的外周血单个核细胞(PBMC)的转录组特征及免疫状态。方法:使用scRNA-seq技术对MHD患者PBMC进行了研究,揭示其在相关疾病中的状态及分子特性的变化。采用无监督聚类和注释分析对PBMC进行了分类和鉴别,对主要细胞类型进行了差异基因富集和细胞间通讯分析。同时,通过分析代谢组学数据集和临床实验室指标进行进一步验证。结果:成功建立了MHD患者PBMC的转录组图谱,鉴定了8种主要细胞类型。通过与健康对照组进行差异基因功能富集分析,发现MHD患者的淋巴细胞和单核细胞炎症相关通路富集评分显著上升,B淋巴细胞的脂质代谢通路富集评分下降,而单核细胞的脂质通路富集评分则呈上升趋势。细胞通讯结果显示,T细胞和单核细胞在多种信号通路中扮演着发送者和接收者的角色。此外,代谢组学分析表明,患者外周血中脂质代谢产物增多。临床实验室结果进一步验证了患者存在较高的炎症和脂质水平。结论:scRNA-seq揭示MHD患者外周循环血液中长期伴有免疫失调、慢性炎症及脂质代谢的紊乱。

关键词：单细胞RNA测序维持性血液透析单个核细胞脂质代谢

利托那韦抗HTLV-1病毒侵染及抑制成人T细胞白血病细胞增殖机制研究

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中国药学杂志 2024年第8期59卷 676-686页

作者：任欣欣王莹朱圣宇张馨逸王旻然徐玲玲赵铁军浙江师范大学生命科学学院浙江金华321004 浙大城市学院医学院杭州310015

目的研究利托那韦(ritonavir)对人类T细胞白血病病毒1型(human T-cell leukemia virus type-1,HTLV-1)病毒侵染及成人T细胞白血病(adult T-cell leukemia,ATL)细胞恶性增殖抑制作用,并探讨其分子机制。方法采用CCK-8和克隆形成实验检测r... 详细信息

目的研究利托那韦(ritonavir)对人类T细胞白血病病毒1型(human T-cell leukemia virus type-1,HTLV-1)病毒侵染及成人T细胞白血病(adult T-cell leukemia,ATL)细胞恶性增殖抑制作用,并探讨其分子机制。方法采用CCK-8和克隆形成实验检测ritonavir对多种ATL细胞增殖的影响;流式细胞术、双荧光素酶报告基因技术、实时定量聚合酶链反应(qPCR)和Western blot检测ritonavir对HTLV-1病毒侵染的影响;流式细胞术检测ritonavir对ATL细胞周期和凋亡的影响。结果Ritonavir能够抑制4种ATL细胞株的增殖及HTLV-1阳性细胞株的克隆性增殖,前者具有明显的量效关系,且对HTLV-1阳性细胞株的抑制作用更明显(P<0.05)。阳性细胞株与JETWT35细胞共培养后立即加入ritonavir,药物可明显下调后者红色荧光蛋白的表达,抑制HTLV-1病毒侵染到受体细胞(P<0.01)。阳性细胞株和Jurkat细胞共培养体系中立即加入ritonavir后,受体细胞中HTLV-1相关病毒基因Tax等mRNA水平均有抑制作用(P<0.01),而12 h病毒侵染完成后再加入ritonavir,则无这些明显影响。Ritonavir剂量依赖性地抑制阳性细胞株ATL-T细胞表面HTLV-1包膜蛋白亚基gp46的表达,从而抑制HTLV-1病毒的产生和侵染(P<0.01)。Ritonavir将细胞阻滞于G1期,并促进细胞凋亡,且HTLV-1阳性细胞株的凋亡率显著高于阴性细胞株(P<0.05或P<0.01)。结论Ritonavir通过降低WT-Luc病毒启动子活力,下调HTLV-1相关病毒基因(Tax、HBZ、Gag、Pol和Env)表达,以及减少阳性细胞表面HTLV-1包膜蛋白亚基gp46表达从而抑制HTLV-1病毒的产生及侵染,并将细胞阻滞于G1期,诱导其凋亡,从多环节有效抑制ATL细胞增殖。

关键词：利托那韦人类T细胞白血病病毒1型病毒侵染增殖成人T细胞白血病

延长氨甲环酸使用时间有助于减少老年股骨转子间骨折围术期隐性失血

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中国组织工程研究 2024年第36期28卷 5858-5864页

作者：赵燕吴凡李红万盛钰何瑾朱宾仁江从兵四川省自贡市第四人民医院急诊科四川省自贡市643000 四川省自贡市第四人民医院骨一科四川省自贡市643000

背景:股骨转子间骨折好发于老年人,手术后会出现大量的隐性失血,减少隐性失血可以降低并发症和住院时间。目的:评估延长氨甲环酸的使用时间对股骨近端防旋髓内钉治疗转子间骨折围术期隐性失血的影响。方法:选择2022年1月至2023年5月自... 详细信息

背景:股骨转子间骨折好发于老年人,手术后会出现大量的隐性失血,减少隐性失血可以降低并发症和住院时间。目的:评估延长氨甲环酸的使用时间对股骨近端防旋髓内钉治疗转子间骨折围术期隐性失血的影响。方法:选择2022年1月至2023年5月自贡市第四人民医院经急诊收治入院的老年股骨转子间骨折患者共62例,均在牵引床上闭合牵引复位后置入股骨近端防旋髓内钉治疗。根据氨甲环酸的使用时间分为2组,对照组38例在切开皮肤前15-30 min给予氨甲环酸1 g静脉滴注,3 h后追加1 g;试验组24例在对照组的基础上,术后第1天再追加氨甲环酸1 g静脉滴注每12 h一次。术前、术后当天、术后第1,3,5天均复查血常规,统计血红蛋白量和红细胞压积,理论总失血量采用Gross方程计算,同时记录两组患者并发症发生情况。结果与结论:①通过统计学分析,两组患者术中显性出血量相差较小,差异无显著性意义(P>0.05);②试验组围术期血红蛋白下降量、总失血量、隐性失血量低于对照组,差异有显著性意义(P0.05);⑥结果表明,术后延迟氨甲环酸的使用时间,可能有助于减少股骨近端防旋髓内钉治疗股骨转子间骨折的隐性失血量,并不会增加并发症风险。

关键词：氨甲环酸股骨转子间骨折股骨近端防旋髓内钉隐性失血血红蛋白血小板计数