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Separation of the ionospheric and thermospheric contributions in the data from the Triple Ionosophere Photo Meter onboard the Feng-Yun 3E satellite

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Science China Earth Sciences 2025年第1期68卷 172-184页

作者： Fang JIANG tian MAO jin-Song WANG Xiu-Qing HU Xiao-Xin zhang Liping FU Nan JIA tianfang WANG National Space Science Center Chinese Academy of Sciences Beijing Key Laboratory of Space Environment Exploration Key Laboratory of Environmental Space Situation Awareness Technology National Satellite Meteorological Center China Meteorological Administration

The Triple Ionosphere Photo Meter （TRIPM） is a far ultraviolet nadir-view photometer that is onboard the secondgeneration,polar-orbiting Chinese meteorological satellite Feng-Yun 3E （FY-3E）,which was launched on July 5,*** has three channels,and each is used to measure different types of emissions:（1） 135.6 nm airglow produced by the recombination of the O+ions and electrons in the absence of sunlight （nighttime channel）;（2） 135.6 nm airglow from the OI when sunlight is present （daytime/dusk-dawn 135.6 nm channel）;and （3） Airglow in the N2LBH of the TRIPM （daytime/dusk-dawn N2LBH channel）.FY-3E is a satellite operating in the early morning ***,the data are mostly distributed on the dawndusk side or at times when the solar zenith angle is relatively *** this study,combined with simulation calculations,the data are *** further explore the application value of the data products,a model is used to separate the ionospheric radiative recombination contribution from the thermosphere photoelectron impact excitation contribution in the data from the daytime/dusk-dawn 135.6 nm *** approach not only improves the accuracy of O/N2derived from the 135.6 nm channel and N2LBH channel but also provides the ionospheric 135.6 nm radiance at the same time as the *** results show that the 135.6 nm radiance originating from the combination of O+and electrons extracted from the measurement data exhibits similar equatorial anomaly peak structure characteristics and seasonal variations as the corresponding GPS total electron content （TEC） *** the other hand,the separated 135.6 nm radiance generated from the thermosphere photoelectron collision excitation does not contain radiative recombination contributions;thus,the ionosphere influence is greatly avoided when the O/N2is obtained.

关键词： Far ultraviolet 135.6 nm emission intensity Photoelectron impact excitation Radiative recombination excitation

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Nanocarrier-mediated siRNA delivery:a new approach for the treatment of traumatic brain injury-related Alzheimer's disease

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Neural Regeneration Research 2025年第9期20卷 2538-2555页

作者： Jie jin Huajing zhang Qianying Lu linqiang tian Sanqiao Yao Feng Lai Yangfan Liang Chuanchuan Liu Yujia Lu Sijia tian Yanmei Zhao Wenjie Ren Institute of Disaster and Emergency Medicine Tianjin UniversityTianjinChina Key Laboratory for Disaster Medicine Technology TianjinChina Henan Medical Key Laboratory for Research of Trauma and Orthopedics The Third Affiliated Hospital of Xinxiang Medical UniversityXinxiangHenan ProvinceChina Clinical Medical Center of Tissue Engineering and Regeneration Xinxiang Medical UniversityXinxiangHenan ProvinceChina Institutes of Health Central Plain Xinxiang Medical UniversityXinxiangHenan ProvinceChina School of Public Health Xinxiang Medical UniversityXinxiangHenan ProvinceChina

Traumatic brain injury and Alzheimer's disease share pathological similarities,including neuronal loss,amyloid-βdeposition,tau hyperphosphorylation,blood-brain barrier dysfunction,neuroinflammation,and cognitive ***,traumatic brain injury can exacerbate Alzheimer's disease-like pathologies,potentially leading to the development of Alzheimer's *** offer a potential solution by facilitating the delive ry of small interfering RNAs across the blood-brain barrier for the targeted silencing of key pathological genes implicated in traumatic brain injury and Alzheimer's disease.U nlike traditional approaches to neuro regeneration,this is a molecula r-targeted strategy,thus avoiding non-specific drug *** review focuses on the use of nanocarrier systems for the efficient and precise delive ry of siRNAs,discussing the advantages,challenges,and future *** principle,siRNAs have the potential to target all genes and non-targetable protein s,holding significant promise for treating various *** the various therapeutic approaches currently available for neurological diseases,siRNA gene silencing can precisely"turn off"the expression of any gene at the genetic level,thus radically inhibiting disease progression;however,a significant challenge lies in delivering siRNAs across the blood-brain *** have received increasing attention as an innovative drug delive ry tool fo r the treatment of brain *** are considered a potential therapeutic strategy with the advantages of being able to cross the blood-brain barrier,targeted drug delivery,enhanced drug stability,and multifunctional *** use of nanoparticles to deliver specific modified siRNAs to the injured brain is gradually being recognized as a feasible and effective *** this strategy is still in the preclinical exploration stage,it is expected to achieve clinical translation in the future,creating a new field of molecular tar

关键词： blood-brain barrier cognitive dysfunction exosomes gene silencing immunotherapy inorganic nanomaterials liposome nanoparticles neuroinflammation polymer nanoparticles stem cells

Influence of carbon content on microstructure and mechanical properties of 1000 MPa deposited metal by gas metal arc welding

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Journal of Iron and Steel Research International 2019年第5期26卷 512-518页

作者： Tong-bang An jin-shan Wei lin Zhao Ji-guo shan Zhi-ling tian Central Iron & Steel Research Institute Beijing 100081 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

The effects of carbon content (0.078-0.100 wt.%) on the microstructure and properties of 1000 MPa grade deposited metal produced by gas metal arc welding have been investigated. Experimental results show that the microstructure of the deposited metal was mainly composed of martensite, bainite and retained austenite. With increasing carbon content, the proportion of martensite increased, and the amount of bainite was reduced. High carbon content is beneficial to strength, but harmful to impact toughness, and thus, carbon reductions lead to the increase in impact toughness. When the carbon content was 0.100 wt.%, the lowest Charpy absorbed energy of 47 J at — 40℃ for the deposited metal was achieved, the highest yield strength of 1038 MPa was attained, and the yield-to-tensile ratio was more than 0.88, while the highest Charpy absorbed energy of 55.7 J at — 40℃ and the lowest yield strength of 915 MPa were obtained when the deposited metal contains 0.078 wt.% C, and the yield-to-tensile ratio was less than 0.85. It is concluded that bainite fraction and fine effective grain size were the dominant factors to achieve good comprehensive mechanical properties (the required strength and an acceptable toughness) of deposited metals with various carbon contents.

关键词： 1000 MPa grade deposited metal Carbon content Microstructure Strength Gas metal arc welding Impact toughness

Effect of cryogenic rolling and annealing on the microstructure evolution and mechanical properties of 304 stainless steel

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International Journal of Minerals,Metallurgy and Materials 2017年第6期24卷 638-645页

作者： jin-tao Shi Long-gang Hou jin-rong Zuo lin-zhong Zhuang Ji-shan zhang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

Metastable 304 austenitic stainless steel was subjected to rolling at cryogenic and room temperatures, followed by annealing at different temperatures from 500 to 950°C. Phase transition during annealing was studied using X-ray diffractometry. Transmission electron microscopy and electron backscattered diffraction were used to characterize the martensite transformation and the distribution of austenite grain size after annealing. The recrystallization mechanism during cryogenic rolling was a reversal of martensite into austenite and austenite growth. Cryogenic rolling followed by annealing refined grains to 4.7 μm compared with 8.7 μm achieved under room-temperature rolling, as shown by the electron backscattered diffraction images. Tensile tests showed significantly improved mechanical properties after cryogenic rolling as the yield strength was enhanced by 47% compared with room-temperature rolling.

关键词： stainless steel cryogenic rolling annealing microstructural evolution mechanical properties recrystallization

Investigation on bonding interfaces of an SA508 steel billet manufactured by additive forging

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Journal of Iron and Steel Research International 2022年第12期29卷 2016-2023页

作者： Xin-jin zhang tian-sheng Wang Zhi-chao Zhu lin Zhu State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004HebeiChina China First Heavy Industries Co. Ltd.Qiqihaer 161042HeilongjiangChina

An experimental steel billet of SA508 reactor pressure vessel material was manufactured by the additive forging method,and microstructure and mechanical properties of the hot-compression bonding interface were systematically *** result indicated that oxidation levels of bonding interfaces were well controlled using vacuum electron beam *** was easy to discriminate interfaces from base materials during the optical microstructure observation,since interfaces were characterized by grain or phase boundaries in a straight *** results of uniaxial tensile experiments(at 20 and 350°C)and Charpy V-notched impact tests(at 0 and 20°C)showed that fracture behaviour of all those samples appeared at the base material,and bonding interfaces showed advantage of strength and toughness at the forge bonding state.

关键词： Reactor pressure vessel Additive forging Interfacial microstructure Mechanical property

Impacts of Different Dynamic Factors on the Saltwater Intrusion in the Northern Branch of the Yangtze Estuary

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China Ocean Engineering 2019年第6期33卷 673-684页

作者： WANG jin-hua zhang De-bin zhang Wei-sheng zhang jin-shan State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China College of Harbor Coastal and Offshore EngineeringHohai UniversityNanjing 210098China

A 3-D baroclinic numerical model is established to study the temporal and spatial distribution of salinity in the Northern Branch(NB) of the Yangtze Estuary(YE) in response to river runoff, wind and currents. The idealized,process-oriented studies show that the lower river runoff in the dry season is the main driving factor for the spilling over from the NB to the Southern Branch(SB). The NB takes longer time to get in dynamic stable state compared with the SB, as the runoff transfers from the wet season to the dry season. The vertical stratification intensity of the NB has obvious periodic phenomena in the dry season, and the stratification strength is enhanced under the action of low runoff and north wind, which further weakens the vertical transport of water. Momentum balance analysis suggested that the landward net flux increases when considering the influence of the moderate north wind, and the landward flux will enhance if considering the boundary current during the spring tide. With the influence of the boundary current, increases the average salinity of the NB, as well as the intrusion degree from the NB to the *** indicates that the nearshore ocean current of the Yellow Sea is an important factor affecting the saltwater intrusion in the NB of the YE.

关键词： Yangtze Estuary saltwater intrusion ocean currents vertical stratification FVCOM

Lumped parameter model for resonant frequency estimation of a thermoacoustic engine with gas-liquid coupling oscillation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第3期12卷 232-237页

作者： Ke TANG tian LEI Xiao-gang lin Tao jin Yu zhang Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

Gas-liquid coupling oscillation is a novel approach to reducing the resonant frequency and to elevating the pressure amplitude of a thermoacoustic *** a thermoacoustic engine is used to drive low-frequency pulse tube refrigerators,the frequency matching between the thermoacoustic engine and the refrigerator plays an important *** on an acoustic-electric analogy,a lumped parameter model is proposed to estimate the resonant frequency of a standing-wave thermoacoustic engine with gas-liquid coupling ***,a simplified lumped parameter model is also developed to reduce the computation *** resonant frequency dependence on the mean pressure,the gas space volume,and the water column length is computed and *** impact of different working gases on the resonant frequency is also *** effectiveness of the models is validated by comparing the computed results with the experimental data of the gas-liquid coupling oscillation *** increase in the mean working pressure can lead to a rise in the resonant frequency,and a lower resonant frequency can be achieved by elongating the liquid *** comparison with nitrogen and argon,carbon dioxide can realize a lower frequency due to a smaller specific heat ratio.

关键词： Thermoacoustic engine Gas-liquid coupling oscillation Acoustic-electric analogy Resonant frequency

Efficient removal of natural organo-chromium(Ⅲ)through selfcirculating decomplex and immobilization with nanoscale zerovalent iron

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Nano Research 2024年第1期17卷 364-371页

作者： Zhicheng Dong Yunyun Xu Can Wu jin Chao Chen tian zhang lin School of Metallurgy and Environment Central South UniversityChangsha 410083China Chinese National Engineering Research Center for Control&Treatment of Heavy Metal Pollution Changsha 410083China College of Ecology and Environment Chengdu University of TechnologyChengdu 610059China School of Environment and Energy The Key Laboratory of Pollution Control and Ecosystem Restoration in Industry Clusters(Ministry of Education)South China University of TechnologyGuangzhou 510006China

Organo-chromium(III)complex is one of the chromium contaminant species,which would transform to high-toxic Cr(VI)during migrating in the *** natural organo-chromium(III)(NOCr)is difficult to remove by traditional degradation or precipitation methods,due to its high stability and ***,we demonstrated a novel NOCr removing method by transforming it to certain structures similar to Cr-Fe minerals in nature,through a self-circulating decomplex and immobilization mechanism with nano zero-valent iron(nZVI).Taking chromium glycinate(Cr-Gly)as a probe,nZVI showed a high Cr removal efficiency of 99.4%under ambient *** removal process included three stages of adsorption,decomplexation,and ***-Gly was first adsorbed on the surface of nZVI by chemisorption of the oxide ***,the adsorbed Cr-Gly was decomplexed and oxidized to Cr(VI)by·OH and 1O_(2),which were generated from molecular oxygen activated by ***,the released Cr(VI)could be in-situ adsorbed and re-reduced to Cr(III),which was further immobilized in form of Cr-O-Fe *** the Cr-O-Fe complexing structure was similar to that of Cr-Fe minerals(such as chromohercynite)in nature,this work explored a novel and efficient NOCr removing method that was potential to weaken chromium pollution in the environment.

关键词： organo-chromium(III) zero-valent iron adsorption decomplexation Cr immobilization

Twinning Behavior of a Basal Textured Commercially Pure Titanium Alloy TA2 at Ambient and Cryogenic Temperatures

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Journal of Iron and Steel Research International 2016年第1期23卷 74-77页

作者： jin-ru LUO Xiao SONG lin-zhong ZHUANG Ji-shan zhang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

Twinning greatly affects the microstructure and mechanical performance of titanium *** twinning behavior of a basal textured commercially pure titanium TA2 plates rolled to 4% reduction at the ambient and cryogenic temperatures has been *** of the rolled samples were investigated by optical microscope（OM）and the twinning analysis was carried out based on orientation data collected by electron back-scatter diffraction（EBSD）.{1122}contraction twins,{1124}contraction twins and {1012}extension twins have been *** mode activity varied with rolling *** is considered as the dominant deformation mechanism during rolling at both temperatures for the strain *** proportion of grains activates twinning during cryorolling,and greater number and more diverse types of twins are observed;manifestly related to the suppression of dislocation slips at the cryogenic temperature.{1122}contraction twins are the dominate twin type within samples rolled at both ***{1124}contraction twins are observed in the cryorolled sample while there are only a few in the sample rolled at room temperature.A few tiny{1012}twins have been identified in both samples.{1124}contraction twins are preferentially activated at cryogenic deformation temperature and the{1012}extension twins may result in local strain accommodation.

关键词： titanium rolling twinning cryogenic temperature