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Corrosion protection of NiNb metallic glass coatings for 316SS by magnetron sputtering

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Journal of Materials Science & Technology 2021年第20期79卷 88-98页

作者： L.Jiang Z.Q.Chen H.b.lu H.b.Ke Y.Yuan Y.M.Dong X.K.Meng School of Chemistry and Life Sciences Suzhou University of Science and TechnologySuzhou 215009China Institute of Materials Engineering National Laboratory of Solid State MicrostructuresCollege of Engineering and Applied SciencesNanjing UniversityNanjing 210009China Songshan Lake Materials Laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China Institute of Materials Engineering Nanjing UniversityNantong 226019China College of Chemistry and Chemical Engineering Nantong UniversityNantong 226019China

Metallic glasses(MGs)appear as promising anti-corrosion coating materials due to their microstructural and physicochemical ***,we proposed magnetron sputtered NiNb thin film MG coatings(MGCs)with different structures and compositions for corrosion protection of 316 stainless steel in an aggressive saline *** properties of monolayered Ni_(50)Nb_(50) and Ni_(60)Nb_(40),as well as the multilayered Ni_(50)Nb_(50)/Ni_(60)Nb_(40)(at.%)MGCs,were characterized in terms of morphology and microstructural properties,as well as the anticorrosion *** the NiNb MGCs presented compact structure and the monolayered coatings exhibited preferable adhesion properties in comparison with the multilayered *** electrochemical tests and XPS results imply that the monolayered Ni_(50)Nb_(50) MGC with high Nb content resisted corrosion mainly due to the formation of stable passive film that contained abundant Nb_(2)O_(5) species,whereas the Ni_(60)Nb_(40) MGC with high Ni content showed week corrosion protection performance during long-term service due to the dissolution of Ni cations and the devastation of the coating *** with bit worse adhesion and more vulnerable Ni_(60)Nb_(40) layers,the multilayered Ni_(50)Nb_(50)/Ni_(60)Nb_(40) MGC possessed comparable corrosion resistance with the monolayered Ni_(50)Nb_(50) MG coating,which remained stable even after 32 days of *** performance should be ascribed to the combined eff;ect of the repassivation property for the sub-layers,the hindrance of propagation paths of micro-defects,and the obstruction of corrosive species by interfaces in the multilayered coating.

关键词： Magnetron sputtering NiNb Metallic glasses Multilayer Corrosion protection

Sensor-based physical activity, sedentary time, and reported cell phone screen time: A hierarchy of correlates in youth

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Journal of Sport and Health Science 2021年第1期10卷 55-64页

作者： Pedro b.Júdice João P.Magalhães Gil b.Rosa Duarte Henriques-Neto Megan Hetherington-Rauth luís b.Sardinha Exercise and Health Laboratory CIPERFaculty of Human KineticsUniversity of LisbonLisbon 1499-002Portugal Faculty of Physical Education and Sport Lusofona UniversityLisbon 1749-024Portugal

background:Evidence on correlates relies on subjective metrics and fails to include correlates across all levels of the ecologic *** determined which correlates best predict sensor-based physical activity(PA),sedentary time(ST),and self-reported cell phone screen time(CST)in a large sample of youth,while considering a multiplicity of ***:Using sensor-based accelerometry,we assessed the PA and ST of 2179 youths.A χ^2 automatic interaction detection algorithm was used to hierarchize the correlates associated with too much ST(>50th percentile),insufficient moderate-to-vigorous PA(MVPA)(being inactive consisted of being a girl,not having sport facilities in the neighborhood,and not perceiving the neighborhood as a safe place,whereas in the youth 15-18 years old,the correlate for being inactive was not performing sports(9.7%chance of being active).The correlates for predicting high ST in the younger group was not performing sports(55.8%chance for high ST),and in the older group,the correlates were not owning a pet,perceiving the neighborhood as safe,and having inactive parents(63.7%chance for high ST).In the younger group,the greatest chances of having high CST were among those who were in the last elementary school years,who were girls,and who did not have friends in the neighborhood(73.1%chance for high CST),whereas in the older group,the greatest chance for having high CST was among those who were girls and had a TV in the bedroom(74.3%chance for high CST).Conclusion:To counteract ST and boost MVPA among youths,a specific focus on girls,the promotion of sport participation and facilities,neighborhood safety,and involvement of family must be prioritized.

关键词： Adolescents Environment Objective Sedentary behavior Socioecologic model

Mechanical properties of gas hydrate-bearing sediments during hydrate dissociation

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Acta Mechanica Sinica 2018年第2期34卷 266-274页

作者： X.H.Zhang D.S.luo X.b.lu L.L.Liu C.L.Liu Institute of Mechanics Chinese Academy of SciencesBeijing 100190China College of Engineering University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Gas Hydrate Ministry of Land and ResourcesQingdao 266071China Qingdao Institute of Marine Geology Qingdao 266071China

The changes in the mechanical properties of gas hydrate-bearing sediments(GHbS) induced by gas hydrate(GH) dissociation are essential to the evaluation of GH exploration and stratum instabilities. Previous studies present substantial mechanical data and constitutive models for GHbS at a given GH saturation under the non-dissociated condition. In this paper, GHbS was formed by the gas saturated method, GH was dissociated by depressurization until the GH saturation reached different dissociation degrees. The stress–strain curves were measured using triaxial tests at a same pore gas pressure and different confining pressures. The results show that the shear strength decreases progressively by 30%–90% of the initial value with GH dissociation, and the modulus decreases by 50% –75%. Simplified relationships for the modulus, cohesion, and internal friction angle with GH dissociated saturation were presented.

关键词： Gas hydrate-bearing sediments Dissociation Mechanical properties Shear strength Triaxial test

Effect of n-butanol Extract from Potentilla anserina on Hypoxia-induced Calcium Overload and SERCA2 Expression of Rat Cardiomyocytes

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Chinese Herbal Medicines 2012年第2期4卷 142-149页

作者： Ling-zhi LI[a][b] lu-jun WANG[b] Yue WANG[a][b] Ying CUI[a][b] Jian-yu LI[b] Li ZHANG[b] Yong-liang ZHANG[a][b] Tianjin Key Laboratory for b iomarkers of Occupational and Environmental Hazards Tianjin 300162 China Logistics University of Chinese People's Armed Police Forces Tianjin 300162 China Tianjin Key Laboratory for B iomarkers of Occupational and Environmental Hazards Tianjin 300162 China Logistics University of Chinese People's Armed Police Forces Tianjin 300162 China

Objective To investigate the effect of n-butanol extract from Potentilla anserina(NP)intervention on hypoxia-induced Ca 2+ overload and SERCA2 expression of rat *** Primary cultured myocardial cell from SD neonatal rat(1-3 d)was used in the establishment of hypoxia *** hypoxia for 3 h,the Ca 2+ concentration of myocardial cells was measured with fura-2/AM fluorescent probe,and the biochemical indicator intracellular Ca 2+ -ATPase was examined and the mRNA and its protective protein levels of the sarcoplasmic reticulum(SR)Ca 2+ -ATPases(SERCA2)were assayed with RT-PCR,Western-blotting,and immune-cytochemical staining in each *** The results showed that NP decreased Ca 2+ concentration, increased the activity of Ca 2+ -ATPase,and improved the mRNA and protein expression of SERCA2 in hypoxia-injured myocardial cells as compared with the model *** These results indicate that NP could attenuate the Ca 2+ *** mechanism might be explained as that NP could elevate the SERCA2 level, increase the activity of myocardium in rats,and further enhance the capacity of SR Ca 2+ re-uptake.

关键词： cardiomyocyte hypoxia intracellular Ca 2+ Potentilla anserina sarcoplasmic reticulum

Large eddies induced by local impulse at wall of boundary layer with pressure gradients

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Progress in Natural Science:Materials International 2008年第7期18卷 873-878页

作者： Changgen lu a,b,*, Weidong Caob, Yanmei Zhang b, Jintao Pengb a College of Atmospheric Science, Nanjing University of Information Science & Technology, Nanjing 210044, China b College of Environmental Science and Engineering, Hohai University, Nanjing 210098, China College of Atmospheric Science Nanjing University of Information Science & Technology Nanjing 210044 China College of Environmental Science and Engineering Hohai University Nanjing 210098 China

Large eddies induced by local impulse at the wall with pressure gradients in the boundary layer was studied by direct numerical sim- ulations. The results show that the amplitude evolution, the high and low speed stripes, the formation of streamwise vortices, the ejection and sweeping, inflexions and distortion at the mean velocity profiles, as well as other characteristics, are consistent with the experimental and other numerical results. It is also found that large eddies are easy to be excited with adverse pressure gradient in the boundary layer, and the growth of amplitudes, formation of streamwise vortices and the influencing area etc., are much larger than those with favorable pressure gradient in the boundary layer. In contrast, large eddies are hardly to be induced through local impulse disturbance at the wall with favorable pressure gradients in the boundary layer.

关键词： boundary layer Pressure gradients Impulse Large eddies

Fast synthesis of monodisperse TiO_2 submicrospheres via a modified sol-gel approach

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Rare Metals 2008年第1期27卷 1-4页

作者： WANG Hong＇en LI bo YAN Zaoxuea lu Zhouguang CHENG Ruijing QIAN Donga College of Chemistry and Chemical Engineering Central South University Changsha 410083 China Sinopec Changling Catalyst Division Yueyang 414012 China State Key Laborotory of Powder Metallurgy Central South University Changsho 410083China

Monodisperse titania glycolate submicrospheres were synthesized by a modified sol-gel route, in which ultrasonic treatment was introduced to improve the reaction efficiency. The as-prepared products were characterized by means of Fourier transform infrared spectrum （FT-IR）, transmission electron microscopy （TEM）, powder X-ray diffraction （XRD）, and scanning electron microscopy （SEM）. The results indicate that the as-prepared products are titania glycolate submicrospheres with diameters of 230-330 nm. The average particle diameter is estimated to be about 280 nm. Ultrasonic treatment has an important influence on the morphology of the produced titania glycolates. After calcination at 450°C for 2 h, these titania glycolates were completely converted into anatase TiO2. The morphology of TiO2 particles was well reserved during the calcination process except for a reduction of 18% in the average particle size.

关键词： TiO2 submicrosphere sol-gel monodisperse ultrasonic treatment

bathynotus:A key trilobite taxon for global stratigraphic boundary correlation between Cambrian Series 2 and Cambrian Series 3

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Progress in Natural Science:Materials International 2009年第1期19卷 99-105页

作者： Jin Peng a,b,Yuanlong Zhao b,Jinliang Yuan c,lu Yao b,Hong Yang b a Department of Earth Sciences,Nanjing University,Nanjing 210093,China b College of Resource and Environmental Engineering,Guizhou University(Caijiaguan Campus),Guiyang 550003,China c Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences,Nanjing 210008,China Department of Earth Sciences Nanjing University Nanjing 210093 China College of Resource and Environmental Engineering Guizhou University (Caijiaguan Campus) Guiyang 550003 China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Cambrian trilobite bathynotus is a special morphology of Redlichiid,which is characterized by a wider thorax axis and an 11th macropleural segment bearing a long,backwardly directed ***,its 12th and 13th pleural segments are narrow and they terminate at a fulcrum where they fuse together and to the posterior edge of the long macropleural *** genus is widely distributed,occurring in North America,Siberia,the Altay-Sayan fold belt of Russia,South China,the Tarim basin of China,and *** occurs primarily in deposits of the upper part of the continental slope,at the transition between stable platform settings and subsiding margins of the late Early ***,we recognize three species of bathynotus from China,including *** which is widespread around the *** six species of bathynotus have been reported from Siberia and the Altay-Sayan fold belt area of Russia,data presented here suggest that only three of these species are *** exhibits a short geological range,with its first occurrence late in the unnamed Cambrian Series 2 and the last appearance datum of bathynotus at the boundary of Cambrian Series 2 and Cambrian Series *** late appearance datum(LAD) of bathynotus provides an important global stratigraphic marker of the boundary between Cambrian Series 2 and Cambrian Series 3.

关键词： bathynotus Age Cambrian Series 2 boundary Correlation

Analysis of a passive ankle exoskeleton for reduction of metabolic costs during walking

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Defence Technology（防务技术） 2024年第7期37卷 62-68页

作者： luís Quinto Pedro Pinheiro Sergio b.Goncalves Ivo Roupa Paula Simoes Miguel Tavares da Silva CINAMIL Academia MilitarInstituto Universitario MilitarLisbonPortugal IDMEC Instituto Superior TecnicoUniversidade de LisboaLisbonPortugal

Modern conflicts demand substantial physical and psychological exertion,often resulting in fatigue and diminished combat or operational *** exoskeletons have been developed recently to address these challenges,presenting various limitations that affect their operational or everyday *** article evaluates the performance of a dual-purpose passive ankle exoskeleton developed for the reduction of metabolic costs during walking,seeking to identify a force element that could be applied to the target *** on the 6-min walk test,twenty-nine subjects participated in the study using three different force *** results indicate that it is possible to reduce metabolic expenditure while using the developed ***,the comfort and range of motion results verify the exoskeleton's suitability for use in uneven terrain and during extended ***,the choice of the force element should be tailored to each user,and the control system should be adjustable to optimise the exoskeleton's performance.

关键词： Ankle passive exoskeleton Metabolic cost reduction Dual-use exoskeleton Gait biomechanics

Effects of cryogenic treatment on the thermal physical properties of Cu_(76.12) Al_(23.88) alloy

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Rare Metals 2011年第6期30卷 644-649页

作者： WANG Ping lu Wei WANG Yuehui LIU Jianhua ZHANG Ruijun State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 China College of Civil Engineering andMechanics Yanshan University Qinhuangdao 066004 China Tangshan Vocational Technology College Tangshan 063000 China College of Physics ＆ Chemistry Hebei Normal University of Science ＆ Technology Qinhuangdao 066004 China

The thermal diffusion coefficient, heat capacity, thermal conductivity, and thermal expansion coefficient of Cu76.12Al23.88 alloy before and after cryogenic treatment in the heating temperature range of 25℃ to 600℃ were measured by thermal constant tester and thermal expansion instrument. The effects of cryogenic treatment on the thermal physical properties of CU76,12A123,88 alloy were investigated by comparing the variation of the thermal parameters before and after cryogenic treatment. The results show that the variation trend of the thermal diffusion coefficient, heat capacity, thermal conductivity, and thermal expansion coefficient of CU76.12Al23.88 alloy after cryogenic treatment was the same as before. The cryogenic treatment can increase the thermal diffusion coefficient, thermal conductivity, and thermal expansion coeffi- cient of Cu76.12Al23.88 alloy and decrease its heat capacity. The maximum difference in the thermal diffusion coefficient between the before and after cryogenic treatment appeared at 400℃. Similarly, thermal conductivity was observed at 200℃.

关键词： Cu76.12Al23,88 alloy cryogenic treatment thermal diffusion coefficient thermal expansion coefficient