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MODIFICATION OF sURFACE MECHANICAL PROPERTIEs OF POLYCARBONATE BY B^+ AND O^+ IONs IMPLANTATION

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Acta Metallurgica sinica(English Letters) 2002年第1期15卷 33-38页

作者： s.D. Yao C. sun s.q. zhou C.C. sun Y.H. Lu L. Huang A. Vantomme q. Zhao G. Langouche sch. of Phys. Peking Univ. Beijing 100871 China

By implanting B+ and O+ ions respectively into polycarbonate (PC) plates, the surface mechanical properties of PC have been improved. Measurement by Nano Indenter II showed that the hardness of samples increased 7-25 times than that before implantation; and the modulus of elasticity raised 2-5 times. The wear-resistance was tested by ball crusher; the width and depth of the wear-streak decreased by 1/3-1/2 or even more. The structure, deformation and appearance were analyzed by using Micro-FTIR spectra, EsCA method and the steps instrument. These analyses showed that the structure of PC had been modified: a series of new cross-linking yielded, it depends on the Linear Energy Transition (LET) of implanted ions in the high polymer compounds.

关键词： polycarbonate ion implantation surface modification

First-principles Investigation of Bi segregation at the solder Interface of Cu/Cu_3sn(010)

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Journal of Materials science & Technology 2010年第12期26卷 1057-1062页

作者： X.Y. Pang Z.q. Liu s.q. Wang J.K. shang shenyang National Laboratory for Materials science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Department of Materials science and Engineering University of Illinois at Urbana-Champaign IL 61801 USA

Density functional theory was employed to investigate the bismuth segregation at Cu/Cu3sn（010） interface. Five initial constructions were introduced by adopting the adhesion energy criterion. Among them, the so-called ＂between-Cu＂ construction in which the interface Cu atoms of Cu slab locate along Cu-Cu bond direction in Cu3sn slab was found to be the most energy-favored at an adhesion energy of 1.96 J/m^2. Based on this construction, five possible segregation sites were examined, and the most likely segregation site was determined with adhesion energy as low as 1.06 J/m^2, which was almost half of the initial one. Comparing with other sitest adhesion energies, it was concluded that size effect took a large part in embrittlement. The analyses of atomic structure and electronic density revealed that the slabs shifted away from interfaces due to bismuth segregation, and the atoms around Bi atom were Dressed away. This calculated work agreed aualitativelv with reported experimental results.

关键词： First-principles calculation segregation Bismuth Interface snBi solder

Engineering complex systems applied to risk management in the mining industry

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International Journal of Mining science and Technology 2017年第4期27卷 611-616页

作者： Domingues Maria s.q. Baptista Adelina L.F. Diogo Miguel Tato CERENA - Centre for Natural Resources and the Environment Faculty of Engineering University of Porto Porto 4200-465 Portugal CLEGI-Centre Lusiada of Research and Development in Engineering and Industrial Management University Lusiada-North Vila Nova de Famalicao 4760-108 Portugal

Related to complexity, there is a wide diversity of concepts, ranging from ‘‘systemic" to ‘‘complex", implying a need for a unified terminology. Per different authors, the main drivers of complexity can be found in human behaviour and uncertainty. This complexity, structural or dynamic can be organizational, technological, or nested in their relationship. IsO international standard 31000:2009 definition of risk management ‘‘coordinated activities to direct and control an organization with regard to risk", when applied to economic sectors, industry, services, project, or activity, it requires the use of models or theories as guidelines. Therefore, as its basic elements comprehend human behaviour and/or uncertainty, risk management to be effective and adapted as much as possible to reality, must be operational within complex systems, as already demonstrated in different R&D environments. Risk management faces demanding challenges when approaching specific and endogenous needs, such as the mining sector. This paper presents a multivariable function analysis methodology approach based on complex system modelling and through real data corresponding to a risk management tool in the mining sector.

关键词： Risk Risk management Complex systems Mining Decision making

IMPROVEMENT OF CARBIDE MORPHOLOGY ANDMECHANICAL PROPERTIEs OF Cr12MoV sTEELs

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Acta Metallurgica sinica(English Letters) 2000年第5期13卷 1053-1058页

作者： Cui, X.H. Jiang, q.C. Wang, s.q. He, Z.M. sch. of Mat. sci. and Eng. Jilin Univ. of Technol. Changchun 130025 China

Compared with conventional cast Cr12MoV steel and forged Cr12MoV steels, carbide morphology and properties of modified cast Cr12MoV steels were investigated by performing hardness test, impact test, fracture toughness test, fatigue crack propagation test, metallographic examination and quantitatively metallographic analysis. The results indicate that the carbide morphology in modified cast steel is characterized by uniformly-distributed granular carbide, which is different from that of conventional cast steel, but similar to that of forged steel. the impact toughness of modified cast steel is distinctly increased to 12.75 J/cm2 from 6.8 J/cm2 in the conventional cast steel with networked carbide, because of carbide granulation. Furthermore, The fracture toughness and fatigue-crack-propagation threshold of modified cast steel are not only higher than that of the conventional cast steel, but also higher than that of the forged steels.

关键词： Alloys Carbides Mechanical properties Morphology

EFFECT OF MODIFICATION ON CARBIDE GRANULATION AND ITs MECHANIsM

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Acta Metallurgica sinica(English Letters) 1999年第2期12卷 167-172页

作者： Wang, s.q. Jiang, q.C. Cui, X.H. He, Z.M. Jilin Univ of Technology Changchun China

By the modification, network carbide is disconnected at 1100 degree C through uneven dissolution at higher energy places in carbide, where there is twin or lattice distortion, and is granulated at 1130 degree C through element diffusion. The stability of M//7C//3 carbide is decreased because of the modification reducing the segregation of Cr and Mo, thus the temperature, at which uneven dissolution of carbide commenced, is decreased. Also lattice distortion or defect such as twin in carbide is increased by the modification, which prompts widespread disconnections in carbide. In addition, the modification prompts element diffusion to accelerate the kinetics process of carbide granulation. (Edited author abstract) 6 Refs.

关键词： Carbides Chromium alloys Granulation Modification Morphology

Template-free Fabrication and Luminescent Characterization of Highly Uniform and Monodisperse Y_2O_2s:sm^(3+) Hollow submicrospheres

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Journal of Materials science & Technology 2012年第7期28卷 666-672页

作者： s.q. Deng Z.P. Xue Y.H. Yang q. Yang Y.L. Liu Department of Chemistry Jinan University Guangzhou 510632 China

Well dispersed and homogeneous Y2O2s：sm3＋ hollow submicrospheres were successfully achieved by a template- free solvothermal method combining with a postcalcining process. The crystalstructure and particle morphology were investigated by the X-ray diffraction （XRD）, Fourier transform infrared （FT-IR） spectra, scanning and transmission electron microscopy （sEM and TEM）, respectively. A possible growth mechanism was proposed to reveal the formation process. Luminescence properties of the Y202s：sm3＋ long-lasting phosphor were an- alyzed by measuring the excitation spectra, emission spectra, afterglow decay curve and thermoluminescence curve. The excitation spectra indicated that the phosphor could be excited effectively by the ultraviolet-light emitting diode （UV-LED） or blue LED, and the emission spectra showed that the phosphor could emit red light from 600 to 650 nm.

关键词： Yttrium oxysulfide Hollow submicrosphere Luminescence Long-lasting phosphor

Interannual variability of boreal summer intraseasonal oscillation over the northwestern Pacific influenced by the Pacific Meridional Mode

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Atmospheric and Oceanic science Letters 2025年第1期18卷 6-11页

作者： Haoyu zhou Pang-Chi Hsu Lin Chen Yitian qian Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environmental Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjingChina

During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°s-5°N,150°E-150°W)and the subtropical Northwestern Pacific(10°-20°N,130°E-175°W).The former is well-documented and considered to be influenced by the ENsO,while the latter has received comparatively less attention and is likely influenced by the Pacific Meridional Mode(PMM),as suggested by partial correlation analysis *** elucidate the physical processes responsible for the enhanced(weakened)intraseasonal convection over the subtropical northwestern Pacific during warm(cold)PMM years,the authors employed a moisture budget *** findings reveal that during warm PMM years,there is an increase in summer-mean moisture over the subtropical northwestern *** increase interacts with intensified vertical motion perturbations in the region,leading to greater vertical moisture advection in the lower troposphere and cons.q.ently resulting in convective *** a process is pivotal in amplifying intraseasonal convection *** observational findings were further verified by model experiments forced by PMM-like sea surface temperature patterns.

关键词： Boreal summer intraseasonal oscillation Interannual variability Pacific Meridional Mode Moisture budget analysis

The emerging role of nitric oxide in the synaptic dysfunction of vascular dementia

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Neural Regeneration Research 2025年第2期20卷 402-415页

作者： Xiaorong Zhang Zhiying Chen Yinyi Xiong qin zhou Ling-qiang Zhu Dan Liu Department of Pathology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Jiujiang Clinical Precision Medicine Research Center JiujiangJiangxi ProvinceChina Center for Cognitive science and Transdisciplinary studies Jiujiang UniversityJiangxi ProvinceChina Department of Neurology Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Rehabilitation Affiliated Hospital of Jiujiang UniversityJiujiangJiangxi ProvinceChina Department of Pathophysiology School of Basic MedicineTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

With an increase in global aging,the number of people affected by cerebrovascular diseases is also increasing,and the incidence of vascular dementia-closely related to cerebrovascular risk-is increasing at an epidemic ***,few therapeutic options exist that can markedly improve the cognitive impairment and prognosis of vascular dementia *** in Alzheimer’s disease and other neurological disorders,synaptic dysfunction is recognized as the main reason for cognitive *** oxide is one of the ubiquitous gaseous cellular messengers involved in multiple physiological and pathological processes of the central nervous ***,nitric oxide has been implicated in regulating synaptic plasticity and plays an important role in the pathogenesis of vascular *** review introduces in detail the emerging role of nitric oxide in physiological and pathological states of vascular dementia and summarizes the diverse effects of nitric oxide on different aspects of synaptic dysfunction,neuroinflammation,oxidative stress,and blood-brain barrier dysfunction that underlie the progress of vascular ***,we propose that targeting the nitric oxide-sGC-cGMP pathway using certain specific approaches may provide a novel therapeutic strategy for vascular dementia.

关键词： endoplasmic reticulum stress endothelial nitric oxide synthase gene therapy nitric oxide NO-sGC-cGMP pathway synaptic dysfunction vascular dementia

Prussian Blue Analogue‑Templated Nanocomposites for Alkali‑Ion Batteries:Progress and Perspective

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Nano-Micro Letters 2025年第1期17卷 216-261页

作者： Jian‑En zhou Yilin Li Xiaoming Lin Jiaye Ye Key Laboratory of Theoretical Chemistry of Environment Ministry of EducationSchool of ChemistrySouth China Normal UniversityGuangzhou 510006People’s Republic of China school of Chemistry and Physics Faculty of ScienceQueensland University of Technology2 George StreetBrisbaneQLD 4000Australia Centre for Materials science Queensland University of Technology2 George StreetBrisbaneQLD 4000Australia

Lithium-ion batteries(LIBs)have dominated the portable electronic and electrochemical energy markets since their commercialisation,whose high cost and lithium scarcity have prompted the development of other alkali-ion batteries(AIBs)including sodium-ion batteries(sIBs)and potassium-ion batteries(PIBs).Owing to larger ion sizes of Na^(+)and K^(+)compared with Li^(+),nanocomposites with excellent crystallinity orientation and well-developed porosity show unprecedented potential for advanced lithium/sodium/potassium *** enticing open rigid framework structures,Prussian blue analogues(PBAs)remain promising self-sacrificial templates for the preparation of various nanocomposites,whose appeal originates from the well-retained porous structures and exceptional electrochemical activities after thermal *** review focuses on the recent progress of PBA-derived nanocomposites from their fabrication,lithium/sodium/potassium storage mechanism,and applications in AIBs(LIBs,sIBs,and PIBs).To distinguish various PBA derivatives,the working mechanism and applications of PBA-templated metal oxides,metal chalcogenides,metal phosphides,and other nanocomposites are systematically evaluated,facilitating the establishment of a structure–activity correlation for these *** on the fruitful achievements of PBA-derived nanocomposites,perspectives for their future development are envisioned,aiming to narrow down the gap between laboratory study and industrial reality.

关键词： Prussian blue analogues self-sacrificial template Lithium-ion batteries sodium-ion batteries Potassium-ion batteries