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Chinese Journal of Mechanical Engineering 2024年第1期37卷 40-61页

作者： Yunfan Yang Feifan Chai Pengfei Liu liang ling Kaiyun Wang Wanming Zhai State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 610031China

Wheel polygonal wear can immensely worsen wheel/rail interactions and vibration performances of the train and track,and ultimately,lead to the shortening of service life of railway *** present,wheel/rail medium-or high-frequency frictional interactions are perceived as an essential reason of the high-order polygonal wear of railway wheels,which are potentially resulted by the flexible deformations of the train/track system or other external *** this work,the effect of wheel/rail flexibility on polygonal wear evolution of heavy-haul locomotive wheels is explored with aid of the long-term wheel polygonal wear evolution simulations,in which different flexible modeling of the heavy-haul wheel/rail coupled system is ***,the mitigation measures for the polygonal wear of heavy-haul locomotive wheels are *** results point out that the evolution of polygonal wear of heavy-haul locomotive wheels can be veritably simulated with consideration of the flexible effect of both wheelset and *** of mixed-line operation of heavy-haul trains and application of multicut wheel re-profiling can effectively reduce the development of wheel polygonal *** research can provide a deep-going understanding of polygonal wear evolution mechanism of heavy-haul locomotive wheels and its mitigation measures.

关键词： Heavy-haul locomotive Wheel polygonal wear Wheel/rail flexibility Long-term polygonal wear evolution Mitigation measures

High Temperature Iron Ethylene Polymerization Catalysts Bearing N,N,N'-2-(1-(2,4-Dibenzhydryl-6-fluorophenylimino)ethyl)-6-(1-(arylphenylimino)ethyl)pyridines

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Chinese Journal of Polymer Science 2024年第2期42卷 188-201,I0007页

作者： Chantsalnyam Bariashir Qiu-Yue Zhang Bayasgalan Ulambayar Gregory A.Solan Tong-ling liang Wen-Hua Sun Institute of Chemistry and Chemical Technology Mongolian Academy of SciencesUlaanbaatar13330Mongolia Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China Department of Chemistry University of LeicesterUniversity RoadLeicesterLE17RHUK State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China

The N,N,N'-ferrous chloride complexes,[2-{CMeN(2,4-(CHPh)_(2)-6-FC_(6)H_(2))}-6-(CMeNAr)C_(5)H_(3)N]FeCl_(2)(Ar=2,6-Me_(2)C_(6)H_(3) Fe1,2,6-Et_(2)C_(6)H_(3)Fe2,2,6-^(i)Pr_(2)C_(6)H_(3) Fe3,2,4,6-Me_(3)C_(6)H_(2) Fe4 and 2,6-Et_(2)-4-MeC_(6)H_(2) Fe5),each possessing one N-2,4-dibenzhydryl-6-fluorophenyl group,were readily synthesized from their respective unsymmetrical bis(imino)pyridines,*** identification of Fe2 highlighted the variation in the steric properties provided by the dissimilar N-aryl *** pre-treatment with either MAO or MMAO,complexes Fe1-Fe5 all displayed,at an operating temperature of 80℃,high activities for ethylene polymerization with levels falling in the order:Fe4> Fe1> Fe5> Fe2> ***,Fe4/MAO displayed the highest activity of 1.94×10^(7) g_(PE)·mol_(Fe)^(-1)·h^(-1) of the study with only a modest loss in performance at 90℃.Generally,the resulting polyethylenes were highly linear(T_(m) range:122-132℃),narrowly disperse and of low molecular weight(M_(w) range:6.73-46.04kg·mol^(-1)),with the most sterically hindered Fe3 forming the highest molecular weight polymer of the ***-group analysis by ^(1)H-and ^(13)CNMR spectroscopy revealed saturated alkyl(n-propyl and i-propyl) and unsaturated vinyl chain ends indicative of the role of both β-H elimination and chain transfer to aluminum as termination *** comparison with previou sly reported iron precatalysts with similar tridentate ligand skeletons,it is evident that the introduction of a large benzhydryl group in combination with a fluorine as the ortho-substituents of one N-aryl group has the effect of enhancing thermal stability of the iron polymerization catalyst whilst maintaining appreciable polymer molecular weight.

关键词： Iron catalyst Ethylene polymerization Linear polyethylene Fluoride effect Thermal stability

Rhegmatogenous retinal detachment in highly myopic eyes with implantable collamer lens

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 392-396页

作者： Jun Li Chong-Lin Chen Jia-Qing Li Xiao-ling liang Chun Zhang State Key Laboratory of Ophthalmology Zhongshan Ophthalmic CenterSun Yat-sen UniversityGuangdong Provincial Key Laboratory of Ophthalmology and Visual ScienceGuangzhou 510060Guangdong ProvinceChina

AIM:To investigate the clinical characteristics,treatment methods and outcomes of rhegmatogenous retinal detachment(RRD)in highly myopic eyes with implantable collamer lens(ICL).METHODS:High myopia patients who received treatment for nontraumatic RRD after ICL implantation surgery at the Retinal Department of Zhongshan Ophthalmic Center from Jan 2018 to Dec 2022 were *** ophthalmologic examinations including visual acuity measurement and digital fundus photography were performed in each ***:A total of nine RRD eyes from nine patients who received V4c-ICL implantation were *** mean time from ICL implantation surgery to the diagnosis of RRD was 32.44±22.56mo(range,1-60mo).At the initial visit for RRD,giant retinal tear(GRT),horseshoe tear,simple round hole,and horseshoe tear combined with round hole were detected in 3,3,2,and 1 eye(s),respectively,with maculaoff in *** patients received surgical treatment,and one patient was treated by retinal laser photocoagulation *** ICL was preserved in 7 *** the last followup,the mean best corrected visual acuity(BCVA)improved significantly from 1.76±1.06 logMAR at presentation to 0.81±1.01 logMAR(P=0.035),and no case of recurrent retinal detachment was ***:The morphological presentation of retinal breaks is diverse in this *** ICL can be preserved in most cases during the course of retinal detachment repair surgery in our data,companied with acceptable visual and anatomical outcomes.

关键词： high myopia implantable collamer lens rhegmatogenous retinal detachment

Metabolic disorders and hepatitis: Insights from a Mendelian randomization study

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1775-1790页

作者： ling-Bo liang Xiang-Ping Liu Ting-Rui Mao Qiao-Li Su General Practice Ward General Practice Medical CenterWest China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Primary Health Care The Fourth People’s Hospital of Dazhu CountyDazhou 635100Sichuan ProvinceChina

BACKGROUND Hepatitis is a systemic disease that often results in various ***-bolic disorders,the most common comorbidities in clinical practice,were selected for this *** To investigate the causal relationship between comorbidities and hepatitis trea-tment *** A total of 23583378 single nucleotide polymorphisms from 1248743 cases and related summaries of genome-wide association studies were obtained from online public databases.A two-sample Mendelian randomization(MR)was performed to investigate causality between exposure[type 2 diabetes mellitus(T2D),hyperlipidemia,and hypertension]and outcome(chronic hepatitis B or C in-fections).RESULTS The data supported the causal relationship between comorbidities and hepatitis infections,which will affect the severity of hepatitis progression and will also provide a reference for clinical *** three exposures showed a link with progression of both hepatitis B(T2D,P=0.851;hyperlipidemia,P=0.596;and hypertension,P=0.346)and hepatitis C(T2D,P=0.298;hyperlipidemia,P=0.141;and hypertension,P=0.035).CONCLUSION The results of MR support a possible causal relationship between different ex-posures(T2D,hyperlipidemia,and hypertension)and chronic hepatitis progression;however,the potential mechanisms still need to be elucidated.

关键词： Hepatitis Comorbidity Type 2 diabetes mellitus Hyperlipidemia Hypertension

Train post‑derailment behaviours and containment methods:a review

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Railway Engineering Science 2024年第1期32卷 59-80页

作者： Zhao Tang Yuwei Hu Shuangbu Wang liang ling Jianjun Zhang Kaiyun Wang State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu 610031China Institute of Smart City and Intelligent Transportation Southwest Jiaotong UniversityChengdu 610031China National Centre for Computer Animation Bournemouth UniversityDorsetUK

Railway accidents,particularly serious derailments,can lead to catastrophic ***,it is essential to prevent derailment escalation to reduce the likelihood of severe *** post-derailment behaviours and containment methods play a critical role in preventing derailment escalation and providing passive safety protection and accident prevention in the event of a ***,despite the increasing attention on this field from academia and industry in recent years,there is a lack of systematic exploration and summarization of emerging applications and containment methods in train post-derailment *** this reason,this paper presents a comprehensive review of existing studies on train post-derailment behaviours,encompassing various topics such as post-derailment contact-impact models,dynamic modelling and simulation techniques,and the primary factors influencing post-derailment ***,this review introduces and elucidates substitute guidance mechanisms(SGMs),which serve as railway-specific passive safety protection and accident prevention *** various types of SGMs are depicted,and their ongoing developments and applications are explored in *** review additionally points out several unresolved challenges including the adverse effects of SGMs,and proposes future research directions to advance the theoretical understanding and practical application of train post-derailment behaviours and containment *** review seeks to be a valuable reference for railway industry professionals in preventing catastrophic derailment consequences through post-derailment containment methods.

关键词： Railway passive safety Railway accident prevention Post-derailment behaviours Substitute guidance mechanisms(SGMs) Contact-impact model

High-Performanceα-Diimine Nickel Complexes for Facile Access of PE Elastomers with Exceptional Material Properties

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Chinese Journal of Polymer Science 2024年第5期42卷 620-635,I0008页

作者： Li-Dong Qin Xin-Yu Wang Qaiser Mahmood Zhi-Xin Yu Yi-Zhou Wang Song Zou Tong-ling liang Wen-Hua Sun School of Pharmaceutical Sciences Changchun University of Chinese MedicineChangchun130117China Chemistry and Chemical Engineering Guangdong Laboratory Shantou515031China Key Laboratory of Engineering Plastics and Beijing National Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China

For practicable elastomeric polyethylene,achieving high catalyst thermal stability and activity,along with precise control of polymer properties such as branching density,molecular weights,and distribution,is crucial but *** this study,two sets of symmetricalα-diimine nickel complexes,each comprising four nickel bromide or chloride complexes,were synthesized and investigated their performance for ethylene polymerization under various reaction *** activation with either Et2AlCl or MMAO cocatalysts,these complexes displayed not only high activity but also generated high molecular weight polyethylenes with controlled polydispersity and a substantial number of *** catalyst with the least steric hindrance displayed the remarkable high activity(up to 1.2×10^(7) g·mol^(-1)·h^(-1)).Notably,nickel bromides demonstrated higher activity compared to their chloride *** investigation into the effect of reaction temperature on catalytic performance revealed that NiBrMe-MMAO system displayed high thermal stability(activity up to 2.51×10^(6) g·mol^(-1)·h^(-1) at 100℃)and consistently yielded high polymer molecular weights with narrow polydispersity over a broad temperature range of 30-100℃.Of significant note,mechanical analysis of the resulting polyethylene demonstrated excellent ultimate tensile strength and high strain at ***,the polyethylene sample prepared at 100℃exhibited ultimate tensile strength up to 10 MPa with 1863%maximum strain at break and a strain recovery of up to 54.9%after ten cycles at a fixed strain of 300%,indicating excellent material properties of prepared thermoplastic polyethylene elastomers(TPE).

关键词： Thermoplastic polyethylene elastomers α-Diimine nickel pre-catalysts Ethylene polymerization Mechanical properties Highly branched polyethylene

Dual-functional microneedle with programmatic regulation of macrophage for autoimmune psoriasis treatment

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Nano Research 2024年第8期17卷 7436-7448页

作者： Ze Qiang Zhao Bo Zhi Chen Jia Li Gan Yun Hao Feng ling liang lingyun Yu Zi Yi Wang Samin Abbaszadeh Mohammad-Ali Shahbazi Ruixing Yu Xin Dong Guo State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Beijing Laboratory of Biomedical Materials College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China China-Japan Friendship Hospital Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100029China Department of Dermatology China-Japan Friendship HospitalBeijing 100029China Department of Pharmaceutical Biomaterials School of PharmacyZanjan University of Medical SciencesZanjan 45139-56184Iran Department of Biomaterials and Biomedical Technology University Medical Center GroningenUniversity of GroningenAntonius Deusinglaan 19713 AV GroningenThe Netherlands W.J.Kolff Institute for Biomedical Engineering and Materials Science University of GroningenAntonius Deusinglaan 19713 AV GroningenThe Netherlands

Modulating the immune microenvironment to establish sustained positive feedback within immune pathways represents a promising avenue for the treatment of ***,the precise and efficient delivery of therapeutic systems to the subcutaneous basal layer to modulate immune disorders is a major challenge in the treatment of autoimmune *** this project,we introduce a dual-functional microneedle(DF-MN)designed to combine MNs with multiple release kinetics and immunotherapy,the programmed treatment is achieved through segmented design of the MN structure,realizing the unification of rapid and long-lasting treatment of autoimmune *** vivo imaging results showed that GelMA@M-CSF showed fluorescent signals after 5 days of delivery to subcutaneous tissues,whereas HA@IL-13 showed minimal fluorescent signals after 2 *** multistage release behavior of MNs and the diffusion mechanism of drugs were explained at the molecular level,in combination with coarse-grained molecular ***,DF-MN can successfully induce macrophage reprogramming in vitro and ameliorate overall symptoms in a psoriasis mice model,suggesting that it has the potential to be an effective strategy for the treatment of psoriasis and portends to be a transformative platform for the treatment of other autoimmune diseases.

关键词： microneedle psoriasis M2 macrophage immunoregulation

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技术和数据知识产品交易平台模式及实现路径

科学学研究 2024年第2期42卷 355-365页

作者：胡锴熊焰梁玲玲卓训方上海应用技术大学中欧知识产权学院上海200235 上海数据交易所有限公司上海201203

知识产品交易服务创新有助于加快培育统一的技术和数据市场。通过技术、数据交易企业服务和产品的嵌套式多案例研究,归纳了一种开放型白标服务平台下的知识产品交易模式,分析了该模式的内涵与服务架构,结合应用场景与具体行业说明了该... 详细信息

知识产品交易服务创新有助于加快培育统一的技术和数据市场。通过技术、数据交易企业服务和产品的嵌套式多案例研究,归纳了一种开放型白标服务平台下的知识产品交易模式,分析了该模式的内涵与服务架构,结合应用场景与具体行业说明了该模式的技术实现路径。研究有三点主要发现,一是开放型白标服务平台模式以知识资源持有企业为核心面向,重点强调服务定制化和生态开放性;二是该模式建立于知识产品交易所“后台—中台—前台”的统一服务架构之下,并根据知识产品生产流通、外部获取、共享应用等不同应用场景而具有差异化的服务特点,模式运行依赖于平台服务体系所拥有的生产加工、汇聚整合、共享连通、价值变现等综合能力;三是该模式对于交易产业链创新链具有牵引全链赋能和驱动双链融合的作用。研究结论对改变当前技术和数据交易平台困境、实现要素市场化配置的政策设计具有启示意义。

关键词：技术要素市场数据要素市场技术交易数据知识产权产业链创新链融合

水平MJS工法黏土地层成桩特性及渗透性分析

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铁道建筑技术 2024年第3期 35-39页

作者：梁凌中铁十六局集团北京轨道交通工程建设有限公司北京100018

为研究黏土地层中水平喷射注浆工法(Metro Jet System, MJS)的成桩性能和隔水能力,以苏州地铁临顿路站下穿工程为背景,在相似地层进行试桩试验,揭示水平MJS试桩成桩特性;同时,测试及对比室内水泥土与现场MJS水泥土的渗透系数,以评估其... 详细信息

为研究黏土地层中水平喷射注浆工法(Metro Jet System, MJS)的成桩性能和隔水能力,以苏州地铁临顿路站下穿工程为背景,在相似地层进行试桩试验,揭示水平MJS试桩成桩特性;同时,测试及对比室内水泥土与现场MJS水泥土的渗透系数,以评估其隔水性能。试验结果表明:当土层均匀时,加固体通常呈切割搅拌型,其形状受土层性质、施工参数和重力作用等影响,通常不是半圆形,其竖向“直径”常大于水平向“直径”;室内水泥土渗透系数和现场试桩芯样渗透系数接近,绝大部分样品渗透系数在2×10^(-8)~8×10^(-8) cm/s的范围内,展现出较好的隔水性能。

关键词：全方位高压喷射注浆盾构下穿水泥土成桩效果渗透系数

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白藜芦醇-盐酸巴马汀共晶水合物的制备、晶体结构及溶解性研究

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中草药 2024年第11期55卷 3659-3667页

作者：梁玲李延广郭全虎娄本勇闽江学院材料与化学工程学院福州市药物制剂与检测行业技术创新中心福建福州350108

目的开发新的共晶以提高白藜芦醇的溶解度,进而为改善白藜芦醇生物利用度提供参考。方法采用溶剂悬浮法制备了一种新的白藜芦醇-盐酸巴马汀共晶水合物(resveratrol-palmatine chloride cocrystal hydrate,RES-2PCl·H_(2)O),利用单晶X... 详细信息

目的开发新的共晶以提高白藜芦醇的溶解度,进而为改善白藜芦醇生物利用度提供参考。方法采用溶剂悬浮法制备了一种新的白藜芦醇-盐酸巴马汀共晶水合物(resveratrol-palmatine chloride cocrystal hydrate,RES-2PCl·H_(2)O),利用单晶X射线衍射、粉末X射线衍射和傅里叶变换红外光谱对其结构进行表征,并利用差示扫描量热、动态水蒸汽吸附、高效液相色谱分析等对共晶水合物的稳定性、溶解度及溶出速率等进行考察。结果所制备的RES-2PCl·H_(2)O具有较高的纯度和均匀性,分子间存在较强的氢键作用,白藜芦醇、盐酸巴马汀及水分子通过O-H…O与O-H…Cl^(−)的氢键作用形成一维链状结构,链与链间又通过C-H…O作用形成二维层状结构,层与层之间通过分子间弱作用力进而形成堆积结构。药物稳定性测试证实共晶水合物在高温、高湿或强光照射等长期储存条件下是物理稳定的。溶解性研究表明不溶性白藜芦醇与可溶性盐酸巴马汀共结晶影响了2种药物的溶解性能,且促进了白藜芦醇的释放同时延缓了盐酸巴马汀的释放。结论制备并系统表征了一种新的RES-PCl共晶水合物,为利用共结晶技术开发白藜芦醇药物-药物共晶提供借鉴。

关键词：药物共晶白藜芦醇盐酸巴马汀氯离子溶解度生物利用度溶剂悬浮法