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journal of Magnesium and Alloys 2024年第1期12卷 394-404页

作者： Lokesh Choudhary Parama Chakraborty Banerjee R.K.Singh Raman Derrek E.Lobo Christopher D.Easton Mainak Majumder frank Witte jörg f.Löffler Department of Mechanical and Aerospace Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Department of Chemical and Biological Engineering Monash UniversityClayton CampusMelbourneVIC 3800Australia Nanoscale Science and Engineering Laboratory(NSEL) Bldg 37Monash UniversityClayton CampusMelbourneVIC 3800Australia CSIRO Materials Science and Engineering Bayview AvenueClaytonVIC 3168Australia julius Wolff Institute and Berlin Brandenburg Center for Regenerative Therapies Charité–Universitätsmedizin BerlinAugustenburger Platz 113353 BerlinGermany Laboratory of Metal Physics and Technology Department of MaterialsETH Zurich8093 ZurichSwitzerland

Biodegradable implants are critical for regenerative orthopaedic procedures,but they may suffer from too fast corrosion in human-body *** necessitates the synthesis of a suitable coating that may improve the corrosion resistance of these implants without compromising their mechanical *** this study,an AZ91 magnesium alloy,as a representative for a biodegradable Mg implant material,was modified with a thin reduced graphene oxide(RGO)-calcium carbonate(CaCO_(3))composite *** analytical and in-vitro electrochemical characterization reveals that this coating significantly improves the corrosion resistance and mechanical integrity,and thus has the potential to greatly extend the related application field.

关键词： Graphene coating Biodegradable implant Hydroxyapatite Corrosion Magnesium alloy

fjord-Type AIEgens Based on Inherent Through-Space Conjugation

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CCS Chemistry 2024年第7期6卷 1739-1747页

作者： ye-Qiang Han yuan Xie jianyu Zhang Shiyu tan Haoke Zhang Ben Zhong tang jonathan L.Sessler feihe Huang Stoddart Institute of Molecular Science Department of ChemistryZhejiang UniversityHangzhou 310058 Zhejiang-Israel joint Laboratory of Self-Assembling functional Materials ZJU-Hangzhou Global Scientific and Technological Innovation CenterZhejiang UniversityHangzhou 311215 MOE Key Laboratory of Macromolecular Synthesis and functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310058 Center for AIE Research College of Materials Science and EngineeringShenzhen UniversityShenzhen 518061 Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionThe Hong Kong University of Science and TechnologyKowloonHong Kong 999077 School of Science and Engineering Shenzhen Institute of Aggregate Science and TechnologyThe Chinese University of Hong KongShenzhen(CUHK-Shenzhen)Guangzhou 518172 Department of Chemistry The University of Texas at AustinAustinTexas 78712-1224 Green Catalysis Center and College of Chemistry Zhengzhou UniversityZhengzhou 450001

Through-space conjugation(TSC)is a noncovalently electronic interaction that is emerging as a potential complement to through-bond conjugation(TBC)-based strategies for constructing luminescent ***,the design of efficient luminogens based on TSC is currently challenging due to a lack of established structure-property *** is particularly true in the case of luminogens displaying aggregation-induced emission(AIE)*** this work,three terphenyl derivatives were prepared,and their photophysical properties were systemically *** was found that relative to the corresponding m-and p-linked analogues,the electronic interaction of TBC is weakened while the strength of TSC is commensurately enhanced in the constitutional isomer containing an o-linked fjordtype *** this set of luminogens,the presence of a fjord-type arrangement promotes a transformation from aggregation-caused quenching to *** investigations involving congeneric quaterphenyl and pentphenyl isomers support the universality of the fjord-type unit as a framework for synthesizing AIE-active luminogens(AIEgens)with inherent *** work not only provides a novel set of AIEgens but also establishes the utility of TSC in controlling the photophysical properties of nonconventional and twisted luminogens.

关键词： fjord-type through-space conjugation through-bond conjugation aggregation-induced emission luminescence twisted conformation

The effects of local variations in conditions on carbon storage and release in the continental mantle

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National Science Review 2024年第6期11卷 22-36页

作者： Stephen f.foley Chunfei Chen Dorrit E.jacob School of Natural Sciences Macquarie University Research School of Earth Sciences Australian National University State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences

Recent advances indicate that the amount of carbon released by gradual degassing from the mantle needs to be revised upwards, whereas the carbon supplied by plumes may have been overestimated in the *** in rock types and oxidation state may be very local and exert strong influences on carbon storage and release mechanisms. Deep subduction may be prevented by diapirism in thick sedimentary packages,whereas carbonates in thinner sequences may be subducted. Carbonates stored in the mantle transition zone will melt when they heat up, recognized by coupled stable isotope systems(e.g. Mg, Zn, Ca). There is no single ‘mantle oxygen fugacity’, particularly in the thermal boundary layer(TBL) and lowermost lithosphere, where very local mixtures of rock types coexist. Carbonate-rich melts from either subduction or melting of the uppermost asthenosphere trap carbon by redox freezing or as carbonate-rich dykes in this zone. Deeply derived, reduced melts may.f.rm further diamond reservoirs, recognized as polycrystalline diamonds associated with websteritic silicate minerals. Carbon is released by either edge-driven convection,which tears sections of the TBL and lower lithosphere down so that they melt by a mixture of heating and oxidation, or by lateral advection of solids beneath rifts. Both mechanisms operate at steps in lithosphere thickness and result in carbonate-rich melts, explaining the spatial association of craton edges and carbonate-rich magmatism. High-pressure experiments on individual rock types, and increasingly on reactions between rocks and melts, are fine-tuning our understanding of processes and turning up unexpected results that are not seen in studies of single rocks. future research should concentrate on elucidating local variations and integrating these with the interpretation of geophysical signals. Global concepts such as average sediment compositions and a uniform mantle oxidation state are not appropriate for small-scale processes; an increa

关键词： lithospheric mantle carbonate melts deep carbon cycle craton destruction continental rifts

Buechel Pappas Resurfacing Shoulder Replacement: Evolution and over 40 years of Clinical Experience

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Open journal of Orthopedics 2024年第5期14卷 218-228页

作者： frederick f. Buechel Michael j. Pappas Rutgers Nj Medical School Newark NJ USA South Mountain Orthopaedic Associates South Orange NJ USA New jersey Institute of Technology Newark NJ USA

Background: Early exploration of the semi constrained “floating-Socket” total shoulder replacement (TSR) in 1974 led to a proliferation of various unconstrained designs that allowed resection or retention of the humeral head, depending upon the pathological process involved. Degenerative glenohumeral arthritis with mild to moderate involvement of subchondral bone allowed for a resurfacing option, while severe humeral head involvement required a partial or full humeral head replacement attached to an intramedullary stem for fixation. All components evolved from cemented to cementless application by 1982. The purpose of this paper is to describe the progression of Buechel-Pappas (B-P) shoulder replacement development from the early 1970’s in both cemented and cement less applications. Methods: Clinical evaluations of “floating-Socket” TSR, followed by B-P stem-type, resurfacing types, bipolar-type and revision components, all of which comprise the B-P Shoulder Replacement System, were performed over a 49-year period. Results: “floating-Socket” implants improved the results of simple, constrained ball-in-socket designs, but generally.f.iled by glenoid component loosening in both chimpanzee and human applications. Unconstrained resurfacing-type components, both anatomical humeral head and full proximal humeral components, were quite successful, with minimal failures observed in long-term studies. Bipolar salvage implants, used for severe proximal deficiencies, revisions and massive rotator cuff arthropathy, were also very successful;providing overhead range of motion in many patients. Conclusions: Resurfacing hemiarthroplasty, in patients with intact or repairable rotator cuff mechanisms, gave the most satisfactory results and were the least technically complicated to perform, requiring minimal instrumentation. Resurfacing of full proximal humeral deficiencies, using femoral resurfacing components, gave similar clinical results to more complex semi-constrained devices,

关键词： Total Shoulder Replacement Resurfacing Shoulder Replacement

Dual effect of Cu on the Al3Sc nanoprecipitate coarsening

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journal of Materials Science & Technology 2020年第2期37卷 38-45页

作者： y.H.gao L.f.Cao j.Kuang j.y.Zhang G.Liu j.Sun State Key Laboratory.f.r Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an710049China International joint Laboratory.f.r Light Alloys(Ministry of Education) Chongqing UniversityChongqing 400044China

It is generally considered that the Al3Sc nanoprecipitates are highly thermal stable,mainly due to quite slow Sc diffusion in theα-Al *** this paper,we demonstrate in an Al-Cu-Sc alloy that the Cu atoms have dual effect on the coarsening of Al3Sc *** the one hand,the Cu atoms with high diffusivity tend to accelerate the Al3Sc coarsening,which results from the Cu-promoted Sc *** the other hand,some Cu atoms will segregate at the Al3Sc/matrix interface,which further stabilizes the Al3Sc nanoprecipitates by reducing the interfacial *** between these two effects is tailored by temperature,which rationalizes the experimental findings that the coarsening kinetics of Al3Sc nanoprecipitate is greatly boosted at 300℃-overaging while significantly suppressed at 400℃-overaging.

关键词： Al alloys Precipitate coarsening Interfacial segregation Microstructural evolution

Synchronized off-harmonic probe laser with highly variable pulse duration for laser-plasma interaction experiments

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High Power Laser Science and Engineering 2024年第1期12卷 99-107页

作者： j.Hornung y.Zobus H.Lorenté C.Brabetz B.Zielbauer V.Bagnoud GSI Helmholtzzentrum für Schwerionenforschung GmbH DarmstadtGermany Institut d’Optique UniversitéParis-SaclayPalaiseauFrance Institut für Angewandte Physik Technische Universität DarmstadtDarmstadtGermany

This paper presents the development and experimental utilization of a synchronized off-harmonic laser system designed as a probe for ultra-intense laser±plasma interaction experiments. The system exhibits a novel seed-generation design,allowing for a variable pulse duration spanning over more than three orders of magnitude, from 3.45 picoseconds to 10 nanoseconds. This makes it suitable for various plasma diagnostics and visualization techniques. In a side-view configuration, the laser was employed for interferometry and streaked shadowgraphy of a laser-induced plasma while successfully suppressing the self-emission background of the laser±plasma interaction, resulting in a signal-to-self-emission ratio of 110 for this setup. These properties enable the probe to yield valuable insights into the plasma dynamics and interactions at the PHELIX facility and to be deployed at various laser facilities due to its easy-to-implement design.

关键词： interferometry laser-plasma interaction off-harmonic probe laser streaked shadowgraphy

Semicrystalline Unfused Polymer Donors with Backbone Halogenation toward Cost-Effective Organic Solar Cells

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Chinese journal of Chemistry 2024年第7期42卷 752-759页

作者： yuxin Kong Shijie ju Hongmei Qin Min Hun jee Simeng Xia jiaqi Ren Chao gao jianyu yuan Wenyan Su Han young Woo yuxiang Li School of Materials Science and Engineering Xi'an University of Science and TechnologyXianShaanxi 710054China Department of Chemistry Korea UniversitySeoul 02841Republic of Korea Xi'an Key Laboratory of Liquid Crystal and Organic Photovoltaic Materials State Key Laboratory of Fluorine&Nitrogen ChemicalsXi'an Modern Chemistry Research InstituteXi'anShaanxi 710065China jiangsu Key Laboratory.f.r Carbon-Based functional Materials&Devices Institute of Functional Nano&Soft Materials(FUNSOM)Soochow University199 Ren'ai RoadSuzhouJiangsu 215123China

Developing novel unfused building blocks with simple synthesis and low cost is essential to advance and enrich cost-effective poly-mer donors;however,it remains a challenge due to the lack of efficient molecular ***,a class of low-cost and fully unfused polymer donors with precisely regulated backbone planarity via halogenation was designed and synthesized,namely PDTBTBz-2H,PDTBTBz-2f,and *** polymer donors possess a four-step synthesis route with over 80%yield from cheap raw chemicals comparable to existing low-cost polymer donors,such as *** from the planar backbone via in-corporating the f…S non-covalent interactions,PDTBTBz-2f exhibits more robust j-type aggregation in solution and a long-ranged molecular stacking in film relative to PDTBTBz-2H and ***,the systematical study of PDTBTBz-based organic so-lar cells(OSCs)reveals the close relationship between optimized molecular self-assembly and charge separation/transport regarding backbone halogenation when paired with the non-fullerene acceptor(y6-BO-4f).As a result,the photovoltaic devices based on semicrystalline PDTBTBz-2f achieved a promising power conversion efficiency(PCE)of 12.37%.Our work highlighted the influence of backbone halogenation on the molecular self-assembly properties and a potential unfused backbone motif for further developing cost-effective OSCs.

关键词： Low-cost Polymer donors Backbone halogenation Molecular self-assembly Organic solar cells

地球演化历史中氧逸度变化对壳幔循环启动、风化和超大陆循环的指示

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Science Bulletin 2024年第1期69卷 97-102页

作者：王瑞邬绍宸 Roberto f.Weinberg William j.Collins Peter A.Cawood State Key Laboratory of Geological Processes and Mineral Resources Institute of Earth SciencesChina University of GeosciencesBeijing 100083China frontiers Science Center for Deep-time Digital Earth China University of Geosciences(Beijing)Beijing 100083China School of Earth Atmosphere and EnvironmentMonash UniversityClayton VIC 3800Australia The Institute for Geoscience Research Curtin UniversityPerth WA 6102Australia

We apply a zircon redox index to a global compilation of detrital zircons to track the variation of oxidation state,expressed asΔfMQ,through Earth's *** from I-type rocks,which comprise mantle and crustal igneous protoliths,including tonalite–trondhjemite–granodiorites(TTGs),generally have a high oxidation state(ΔfMQ>0).In contrast,zircons from igneous rocks derived from supracrustal source rocks(S-type)are commonly reduced(ΔfMQy density.f.nction derived from the Gaussian-Kernel-Density-Estimation,we use the maximum likelihood estimation(MLE)to distinguish Stype from I-type zircons through Earth's history using zircon *** S-type magma production shows a ca.600 Ma cyclicity that is closely related to the supercontinent *** link a cyclic drop in redox values after 2.6 Ga to periodic S-type magma generation associated with burial and melting of metasedimentary rocks during supercontinent assembly and ***ΔfMQ of the detrital zircons rise at~3.5 Ga followed by a consistent averageΔfMQ>0 over the last 3 *** that the redox state of magmas is independent of crustal thickness and silica variation,and elevated values are likely more closely related to tectonic setting,we suggest that the consistent averageΔfMQ>0 from ca.3.5 Ga onwards relates to recycling of oceanic lithosphere back into the mantle in what eventually became established as subduction *** more reduced magmas associated with sedimentary sources,became established at 2.6 Ga,presumably in response to continental rocks rising above sealevel,and follow peaks of productivity associated with the supercontinent cycle.

关键词： Oxidation state Supercontinent Weathering Subduction Zircon Granite

Characterization of high-pressure die-cast hypereutectic Al-Si alloys based on microstructural distribution and fracture morphology

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journal of Materials Science & Technology 2019年第6期35卷 1099-1107页

作者： X.y. jiao j. Wang C.f. Liu Z.P. Guo G.D. Tong S.L. Ma y. Bi y.f. Zhang S.M. Xiong School of Materials Science and Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Automobile Safety and Energy Tsinghua University Beijing China China fAW foundry Co. Ltd. Changchun 130011. China

The fracture behavior of high-pressure die-cast hypereutectic(HPDC) Al-Si alloys was investigated using a high-resolution laboratory CT and synchrotron X-ray tomography with a particular focus on the influence of HPDC microstructure. Results showed that microstructure of the alloy was mainly comprised of primary silicon particles(PSPs), Al dendrites, Cu-rich phases and pores. Most of the coarse PSPs, Cu-rich phases and pores were located in the center of the specimen. The rapid solidification of HPDC led to a heterogeneous microstructural feature. Elemental Cu was enriched in the frontiers of solid-liquid interface, causing the formation of large size dendritic arms. The pores were formed in the interdendrites which endured high stress intensity under high applied stress. Microcracks were originated from pores and further connected Cu-rich phases causing intergranular fracture. PSPs worked as obstacles causing piling-up dislocations in the phase interface. In the regions where large size of PSPs enriched in, PSPs ruptured rather than debonded from matrix, indicating transgranular fractures of PSPs. Microcracks originated around pores and PSPs tended to converge on the main cracks to decrease the energy required for crack propagation.

关键词： Hypereutectic Al-Si alloy Primary silicon particles Porosity fracture morphology High pressure die casting

DDAH1 promotes neurogenesis and neural repair in cerebral ischemia

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2097-2118页

作者： Qiming gao Pinfei Ni yilin Wang Peiyun Huo Xiaojie Zhang Sihan Wang fuyao Xiao yixuan Li Wei feng juntao yuan Teng Zhang Qiang Li Boyu fan yuhao Kan Zhirui Li yimiao Qi junfei Xing Zhenghong yang Haixiao Cheng Xinran gao Xiaoyan feng Ming Xue yang Liu yumin Luo Zhongbing Lu yuming Zhao Department of Pharmacology School of Basic Medical SciencesCapital Medical UniversityBeijing 100069China Cerebrovascular Diseases Research Institute and Department of Neurology Xuanwu Hospital of Capital Medical UniversityBeijing 100053China State Key Laboratory.f.r Structural Chemistry of Unstable and Stable Species Institute of ChemistryChinese Academy of SciencesBeijing 100190China College of Life Science University of Chinese Academy of SciencesBeijing 100049China Department of Laboratory Animal School of Basic Medical SciencesCapital Medical UniversityBeijing 100069China Department of Physiology and Pathophysiology School of Basic Medical SciencesCapital Medical UniversityBeijing 100069China

Choline acetyltransferase(ChAT)-positive neurons in neural stem cell(NSC)niches can evoke adult neurogenesis(AN)and restore impaired brain function after injury,such as acute ischemic stroke(AIS).However,the relevant mechanism by which ChAT+neurons develop in NSC niches is poorly *** RNA-seq analysis revealed that dimethylarginine dimethylaminohydrolase 1(DDAH1),a hydrolase for asymmetric NG,NG-dimethylarginine(ADMA),regulated genes responsible for the synthesis and transportation of acetylcholine(ACh)(Chat,Slc5a7 and Slc18a3)after stroke *** dual-luciferase reporter assay.f.rther suggested that DDAH1 controlled the activity of ChAT,possibly through hypoxia-inducible factor 1α(HIf-1α).KC7f2,an inhibitor of HIf-1α,abolished DDAH1-induced ChAT expression and suppressed *** expected,DDAH1 was clinically elevated in the blood of AIS patients and was positively correlated with AIS *** comparing the results among Ddah1 general knockout(KO)mice,transgenic(TG)mice and wild-type(WT)mice,we discovered that DDAH1 upregulated the proliferation and neural differentiation of NSCs in the subgranular zone(SGZ)under ischemic *** a result,DDAH1 may promote cognitive and motor function recovery against stroke impairment,while these neuroprotective effects are dramatically suppressed by NSC conditional knockout of Ddah1 in mice.

关键词： DDAH1 Neurogenesis Neural repair ChAT HIf-1α ACh Stroke ADMA