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Improvement of tensile superelasticity by aging treatment of NiTi shape memory alloys fabricated by electron beam wire-feed additive manufacturing

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Journal of Materials Science & Technology 2023年第14期145卷 185-196页

作者： Ze pu Dong Du Dongqi Zhang Zixiang Li Shuai Xue Rui Xi Xiebin Wang Baohua chang Department of Mechanical Engineering State Key Laboratory of TribologyTsinghua UniversityBeijing 100084China Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJingshi Road 17923Jinan 250061China

For the first time,this work comprehensively studied the effectiveness of precipitation hardening achieved by aging treatment in improving the tensile superelasticity of NiTi alloys fabricated by elec-tron beam wire-feed additive manufacturing(EBAM),which possesses inherent advantages in producing dense and oxidation-free *** treatments under three temperatures(450,350,and 250℃)and different durations were conducted,and the resultant performance of tensile superelasticity,together with the corresponding evolution of precipitation and phase transformation behavior were investigated for the EBAM-fabricated NiTi *** showed that by appropriate aging treatment,EBAM fabricated NiTi alloys could achieve excellent recovery rates of approximately 95%and 90%after the 1st and 10th load/unload cycle for a maximum tensile strain of 6%,which were almost the highest achieved so far by AM processed NiTi alloys and close to those of some conventional NiTi *** improvement of tensile superelasticity benefited from the fine and dispersive Ni4Ti3 precipitates,which could be introduced by aging at 350℃ for 4 h or at 250℃ for 200 ***,the large amount of Ni4Ti3 precipitates would promote the intermediate R-phase transformation and bring a two-stage or three-stage transformation sequence,which depended on whether the distribution of the precipitation was homogeneous or *** work could provide guidance for the production of NiTi alloys with good tensile superelasticity by EBAM or other additive manufacturing processes.

关键词： NiTi shape memory alloys Electron beam Additive manufacturing Aging treatment Tensile superelasticity

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Coherent excitation transfer via the dark-state channel in a bionic system

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Light(Science & Applications) 2012年第1期1卷 128-133页

作者： Hui Dong Da-Zhi Xu Jin-Feng Huang chang-pu Sun State Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China

Light absorption and energy transfer were studied in a bionic system with donors and an *** the optimal case of uniform couplings,this seemingly complicated system was reduced to a three-level L-type *** this observation,we showed that the efficiency of energy transfer through a dark-state channel,which is free of the spontaneous decay of the donors,was dramatically *** the overall average transfer time was evaluated,it was revealed that the time required for transfer through this channel was not *** find the optimal parameters for the present system,we defined a new quantity,output power,which characterizes the average mean output of the whole transfer *** estimated the optimal parameters of the system to achieve the maximum output *** splitting behaviour of the maximum power may be used to explain the phenomenon of photosynthetic systems primarily absorbing two colours of light.

关键词： dark state excitation transfer light harvesting quantum coherence

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Experimental study on the variation of optical remote sensing imaging characteristics of internal solitary waves with wind speed

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Journal of Oceanology and Limnology 2024年第2期42卷 408-420页

作者： zhe chang Lina SUN Tengfei LIU Meng ZHANG Keda LIANG Junmin MENG Jing WANG School of Physics and Optoelectronic Engineering Ocean University of ChinaQingdao 266100China First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Technology Innovation Center for Ocean Telemetry Ministry of Natural ResourcesQingdao 266061China

Optical remote sensing has been widely used to study internal solitary waves(ISWs).Wind speed has an important effect on ISW imaging of optical remote *** light and dark bands of ISWs cannot be observed by optical remote sensing when the wind is too *** relationship between the characteristics of ISWs bands in optical remote sensing images and the wind speed is still *** influence of wind speeds on the characteristics of the ISWs bands is investigated based on the physical simulation experiments with the wind speeds of 1.6,3.1,3.5,3.8,and 3.9 m/*** experimental results show that when the wind speed is 3.9 m/s,the ISWs bands cannot be observed in optical remote sensing images with the stratification of h_(1)∶h_(2)=7∶58,ρ_(1)∶ρ_(2)=1∶*** the wind speeds are 3.1,3.5,and 3.8 m/s,which is lower than 3.9 m/s,the ISWs bands can be obtained in the simulated optical remote sensing *** location of the band’s dark and light extremum and the band’s peak-to-peak spacing are almost not affected by wind ***-significant wind speeds can cause a greater gray difference of the light-dark *** provided a scientific basis for further understanding of ISW optical remote sensing imaging.

关键词： internal solitary wave(ISW) optical remote sensing wind speed characteristics of ISWs bands

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Progress of Fengyun Meteorological Satellites Since 2020

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空间科学学报 2022年第4期42卷 724-732页

作者： ZHANG Peng XU zhe GUAN Min XIE Lizi XIAN Di LIU chang Key Laboratory of Radiometric Calibration and Validation for Environmental Satellites Beijing 100081 National Satellite Meteorological Center(National Center for Space Weather) Beijing 100081

China’s efforts to develop Fengyun meteorological satellites have made major strides over the past 50 years,with the polar and geostationary meteorological satellite series achieving continuously stable operation to persistently provide data and product services *** the end of 2021,19 Chinese self-developed Fengyun meteorological satellites have been launched *** of them are in operation at present,the data and products are widely applied to weather analysis,numerical weather forecasting and climate prediction,as well as environment and disaster *** the last COSPAR report,FY-4B,the first new-generation operational geostationary satellite,and FY-3E,the first early-morning orbit satellite in China’s polar-orbiting meteorological satellite family have been launched in *** characteristics of the two latest satellites and the instruments onboard are addressed in this *** status of current Fengyun Satellites,product and data service and international cooperation and supporting activities has been introduced as well.

关键词： Fengyun meteorological satellite Early morning orbit Product and data service International co-operation and supporting

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Experimental Study on the Variation of Optical Imaging Characteristics with Zenith Angle due to Internal Solitary Waves in Sunglint

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Journal of Ocean University of China 2024年第4期23卷 943-952页

作者： LIU Tengfei SUN Lina chang zhe ZHANG Meng LIANG Keda MENG Junmin WANG Jing School of Physics and Optoelectronic Engineering Ocean University of ChinaQingdao 266100China First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Technology Innovation Center for Ocean Telemetry Ministry of Natural ResourcesQingdao 266061China

Internal solitary waves(ISWs)change the roughness of the sea surface,thus producing dark and bright bands in optical ***,reasons for changes in imaging characteristics with the solar zenith angle remain *** this paper,the optical imaging pattern of ISWs in sunglint under different zenith angles of the light source is investigated by collecting optical images of ISWs through physical *** experiment involves setting 10 zenith angles of the light source,which are divided into area a the optical images of ISWs in the three areas show dark-bright mode,single bright band,and bright-dark mode,which are consistent with those observed by optical remote *** addition,this study analyzed the percentage of the dark and bright areas of the bands and the change in the relative gray difference and found changes in both areas under different zenith angles of the light *** MODIS and ASAR images display a similar brightness-darkness distance of the same ***,the relationship between the brightness-darkness distance and the characteristic half-width of ISWs is determined in accordance with the eKdV theory and the imaging mechanism of ISWs of the SAR ***,the relationship between them in the experiment is almost consistent with the theoretical result.

关键词： internal solitary waves optical imaging characteristic laboratory simulation zenith angle sunglint

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Self-Protection against Triptolide-Induced Toxicity in Human Hepatic Cells via Nrf2-ARE-NQO1 Pathway

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Chinese Journal of Integrative Medicine 2017年第12期23卷 929-936页

作者： ZHOU Ling-ling ZHOU Cong LIANG Xiao-wen FENG zhe LIU Zhang-pu WANG Hao-lu ZHOU Xue-ping School of Pharmacy The First Clinical Medical CollegeNanjing University of Chinese MedicineNanjing 210023China Department of Pharmacy Wuxi No.9 People's HospitalSoochow UniversityWuxi Hand Surgery HospitalWuxiJiangsu Province 214062China Therapeutics Research Centre School of MedicineThe University of QueenslandPrincess Alexandra HospitalWoolloongabba QLD 4102Australia

Objective: To find the signaling pathway of triptolide(TP)-induced liver injury and to reveal whether NF-E2-related factor 2(Nrf2) plays an important role in cellular self-protection. Methods: The L-02 and HepG2 cells were cultured and treated with various concentrations of TP. The cell viability was observed, and the cell medium was collected for detecting the aspartate aminotransferase(ALT), alanine aminotransferase(AST), lactate dehydrogenase(LDH), superoxide dismutase(SOD) and L-glutathione production(GSH) levels. Nrf2 and its downstream target NAD(P)H: quinine oxidoreductase 1(NQO1) and heme oxygenase-1(HO-1) expression, the nuclear translocation of Nrf2, and the binding ability of Nrf2 and antioxidant response element(ARE) were also identified. Meanwhile,shRNA was used to silence Nrf2 in L-02 cells to find out whether Nrf2 plays a protective role. Results: The viability of the L-02 and HepG2 cells treated with TP decreased in a doseand time-dependent manner, and TP(20–80 μg/mL) markedly induced the release of ALT, AST and LDH(P<0.05 or P<0.01), reduced the levels of SOD and GSH(P<0.01), and increased the intracellular reactive oxygen species. Meanwhile, TP augmented the Nrf2 expression in L-02 and HepG2 cells(P<0.05 or P<0.01), induced Nrf2 nuclear translocation, increased the Nrf2 ARE binding activity, and increased HO-1 and NQO1 expressions. Nrf2 knockdown revealed a more severe toxic effect of TP(P<0.05 or P<0.01). Conclusions: Human hepatic cells treated with TP induced oxidative stress, and led to cytotoxicity. Self-protection against TP-induced toxicity in human hepatic cells might be via Nrf2-ARE-NQO1 transcriptional pathway.

关键词： triptolide human hepatic cells NF-E2-related factor 2 oxidative stress liver injury

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Formation and evolution of Emeishan basalt saprolite in vadose zones of Touzhai landslide source rockmass

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Journal of Mountain Science 2017年第6期14卷 1174-1184页

作者： YANG Ji-qing XU Ze-min ZHANG Rui CHEN Ji-pu REN zhe LUO Rong-zhang ZHANG Xiu-shuo Faculty of Civil Engineering and Mechanics Kunming University of Science and Technology College of Architectural Engineering Yunnan Agricultural University

In order to explain the formation process of slope hazards, and to identify the key factors leading to instability of a slope, Emeishan basalt saprolite in vadose zones of the Touzhai landslide in Zhaotong, Yunnan, was studied. The formation and evolution of Emeishan basalt saprolite was examined using, amongst other techniques, field investigations,thin section analysis, scanning electron microscopy(SEM) observations, chemical analysis, physical and water-physical property tests of rock masses. Field observations revealed that the majority of the weathered rock blocks were presented as a concentric layer structure in which an internal corestone was enveloped with several layers of external saprolized crust. Chemical and mineralogical analysis identified that iron was the most sensitive element and that the weathering progress usually started with the oxidation of Fe2+ to Fe3+ in rock blocks. Alkaline elements such as Si, Ca, Mg, Na and K were also dissolved and Fe and Al were concentrated in saprolized crusts. Results indicated that loss on ignition(LOI) also increased significantly. SEM results showed that the weathering intensity of thebasalt blocks decreased gradually from the outside to the inside, and the mineral morphology significantly differed on both sides of the weathering front. The saprolized crusts presented cellular microstructure features due to the generation of micropore and clay minerals. Thin section analysis showed that plagioclase was relatively more stable than pyroxene and chlorite during weathering. With a centripetal propagation of the weathering front, saprolized crusts became thicker and corestones became smaller; fresh Emeishan basalt blocks gradually turned into saprolized blocks. Due to the loose structure and low strength of saprolite, the quality of the Emeishan basalt mass significantly deteriorated, this being a potentially important factor which caused the Touzhai landslide to occur.

关键词： Vadose zone Emeishan basalt Scanning electron microscopy Saprolite Corestone Touzhai landslide

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Molecular fossil and paleovegetation records of paleosol S4 and adjacent loess layers in the Luochuan loess section, NW China

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Science China Earth Sciences 2008年第3期51卷 321-330页

作者： ZHANG HuCai YANG MingSheng ZHANG WenXiang LEI GuoLiang chang FengQin pu Yang FAN HongFang Key Laboratory of Western China’s Environmental Systems Ministry of EducationCollege of Earth and Environment SciencesLanzhou UniversityLanzhou 730000China State Key Laboratory of Lake and Environment Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China

Using gas chromatography-mass spectrometry (GC-MS) technique, a series of biomarkers were identi- fied, including n-alkanes, n-alkane-2-ones, isoprenoid etc. from the loess-paleosol samples collected from the S4 and adjacent L5, L4 of the Luochuan loess section, Northwestern China. Based on these data, especially n-alkanes and high-resolution magnetic susceptibility and grain size data, the pa- leoenvironment and paleovegetation history during S4 was reconstructed. The CPI (Carbon Predomi- nance Index) and correlation between n-alkanes and magnetic susceptibility and grain size data dem- onstrated that the molecular fossils in paleosol and loess layers can reflect the vegetation condition during the loess-paleosol formation, if the allochthonous organic inputs could be excluded reasonably. The ACL (average chain length) index is correlated well with paleomagnetic susceptibility and grain size variations, displaying their good synchrony with warm and humid climate. However, it relatively lagged behind the paleomagnetic susceptibility and the grain size variations when the climate began to deteriorate. During the formation period of paleosol, the n-alkanes was dominated by C31 homologue, indicating that the primary organic input originated from herbs. Our study also demonstrated that the herbs were more flourish than wood plants in Loess Plateau, especially in the Luochuan area during the warm and humid phase, and there was no typical forest vegetation developed in the studied period.

关键词： paleoenvironment Paleosol S4 Luochuan loess section biomarker paleovegetation

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HACE1-mediated NRF2 activation causes enhanced malignant phenotypes and decreased radiosensitivity of glioma cells

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Signal Transduction and Targeted Therapy 2021年第12期6卷 3755-3766页

作者： Chenxing Da Jun pu zhe Liu Jing Wei Yiping Qu Yongxing Wu Bingyin Shi Jian Yang Nongyue He Peng Hou Key Laboratory for Tumor Precision Medicine of Shaanxi Province and Department of Endocrinology The First Affiliated Hospital of Xi’an Jiaotong University710061 Xi’anPeople’s Republic of China Department of Diagnostic Radiology The First Affiliated Hospital of Xi’an Jiaotong University710061 Xi’anPeople’s Republic of China Department of Neurosurgery The First Affiliated Hospital of Xi’an Jiaotong University710061 Xi’anPeople’s Republic of China State Key Laboratory of Bioelectronics Southeast University210096 NanjingPeople’s Republic of China Shanxi Provincial Crops Hospital of Chinese People’s Armed Police Force 710054 Xi’anPeople’s Republic of China

HACE1,an E3 ubiquitin-protein ligase,is frequently inactivated and has been evidenced as a putative tumor suppressor in different types of ***,its role in glioma remains ***,we observed increased expression of HACE1 in gliomas related to control subjects,and found a strong correlation of high HACE1 expression with poor prognosis in patients with WHO grade III and IV as well as low-grade glioma(LGG)patients receiving ***1 knockdown obviously suppressed malignant behaviors of glioma cells,while ectopic expression of HACE1 enhanced cell growth in vitro and in *** studies revealed that HACE1 enhanced protein stability of nuclear factor erythroid 2-related factor 2(NRF2)by competitively binding to NRF2 with another E3 ligase ***,HACE1 also promoted internal ribosome entry site(IRES)-mediated mRNA translation of *** effects did not depend on its E3 ligase ***,we demonstrated that HACE1 dramatically reduced cellular ROS levels by activating NRF2,thereby decreasing the response of glioma cells to ***,our data demonstrate that HACE1 causes enhanced malignant phenotypes and decreased radiosensitivity of glioma cells by activating NRF2,and indicate that it may act as the role of prognostic factor and potential therapeutic target in glioma.

关键词： glioma HACE malignant

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Childhood Adversity Phenotypes and Risky Health Behaviors among Chinese Adolescents: Extending the Concept of Adversity

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Biomedical and Environmental Sciences 2022年第8期35卷 699-710页

作者： WANG Geng Fu YUAN Meng Yuan chang Jun Jie LI Yong Han SU pu Yu Department of Maternal Child and Adolescent HealthSchool of Public HealthAnhui Medical UniversityHefei 230032AnhuiChina Key Laboratory of Population Health Across Life Cycle(Anhui Medical University) Ministry of Education of the People's Republic of ChinaHefei 230032AnhuiChina NHC Key Laboratory of study onabnormal gametes and reproductive tract Hefei 230032AnhuiChina

ObjectiveTo present an approach to phenotyping ACEs and explore the association between ACEs and adolescent health risky behaviors based on the social context of *** Totally,5,726 adolescents aged 12-18 years were investigated about their ACEs in the family,peer,school,and personal domains and the occurrence of six types of risky health behaviors(i.e.,smoking,drinking,sexual intercourse,self-harm,and suicidal ideation and attempts).Latent class analysis(LCA)was used to explore the ACE *** Six latent classes of ACEs were identified,including low adversity,school adversity,school adversity and peer victimization,peer victimization,maltreatment and peer victimization,and high adversity,and associated with risky health behaviors in *** physically punished by a teacher,experiencing sexual abuse,and experiencing family trauma most strongly differentiated from the six AcE classes and were correlated with an increased risk for risky adolescent health *** study supports a positive association between ACEs and risky adolescent health *** victimization,school adversity and associated contexts need to be considered in future ACEstudies.

关键词： Adverse childhood experiences Adolescents Healthy risky behaviors Sexual abuse Peer victimization China

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