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Research in Astronomy and Astrophysics 2024年第6期24卷 227-235页

作者： Xue-Feng Lu Li-Ming Song Ming-yu Ge Shuang-Nan Zhang Jin-Lu Qu Ce Cai cong-Zhan Liu Cheng-Kui Li yu-cong fu Ying-Chen Xu Key Laboratory of Particle Astrophysics Institute of High Energy Physics University of Chinese Academy of Sciences Chinese Academy of Sciences College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal University Department of Astronomy Beijing Normal University

In October 2022, the magnetar SGR J1935+2154 entered the active outburst state. During the episode, the InsightHXMT satellite carried out a long observation that lasted for 20 days. More than 300 bursts were detected, and a certain amount of persistent radiation signals were also accumulated. This paper mainly introduces the results of persistent radiation profile folding and period search based on Insight-HXMT data. At the same time, the burst phase distribution characteristics, spectral lag results of burst, the spectral characteristics of zero-lag bursts and the time-resolved spectral evolution characteristics of high-flux bursts are reported. We found that there is no significant delay feature during different energy bands for the bursts of SGR J1935+2154. The observed zero-lag burst does not have a unique spectrum. The time-resolved spectrum of the individual burst has consistent spectral types and spectral parameters at different time periods of the burst. We also find that the burst number phase distribution and the burst photon phase distribution have the same tendency to concentrate in specific regions of the persistent emission profile.

关键词： dense matter magnetic fields radiation mechanisms: general

Burst Phase Distribution of SGR J1935+2154 Based on Insight-HXMT

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Research in Astronomy and Astrophysics 2023年第3期23卷 68-74页

作者： Xue-Feng Lu Li-Ming Song Ming-yu Ge You-Li Tuo Shuang-Nan Zhang Jin-Lu Qu Ce Cai Sheng-Lun Xie cong-Zhan Liu Cheng-Kui Li yu-cong fu Ying-Chen Xu Tian-Ming Li Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsBeijing 100049China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China College of Physics and Hebei Key Laboratory of Photophysics Research and Application Hebei Normal UniversityShijiazhuang 050024China Institute of Astrophysics Central China Normal UniversityWuhan 430079China

On 2020 April 27,the soft gamma-ray repeater SGR J1935+2154 entered its intense outburst episode again.Insight-HXMT carried out about one month observation of the source.A total number of 75 bursts were detected during this activity episode by Insight-HXMT,and persistent emission data were also accumulated.We report on the spin period search result and the phase distribution of burst start times and burst photon arrival times of the Insight-HXMT high energy detectors and Fermi/Gamma-ray Burst Monitor(GBM).We find that the distribution of burst start times is uniform within its spin phase for both Insight-HXMT and Fermi/GBM observations,whereas the phase distribution of burst photons is related to the type of a burst’s energy spectrum.The bursts with the same spectrum have different distribution characteristics in the initial and decay episodes for the activity of magnetar SGR J1935+2154.

关键词： spectrum Fermi distribution

Spectral and Timing Analysis of the Black Hole Transient MAXI J1631–479 During its 2019 Outburst Observed with Insight-HXMT

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Research in Astronomy and Astrophysics 2022年第11期22卷 21-33页

作者： yu-cong fu L.M.Song G.Q.Ding S.N.Zhang J.L.Qu S.Zhang L.Zhang Q.C.Bu Y.Huang X.Ma Z.X.Yang Y.L.Tuo X.F.Lu D.K.Zhou B.Y.Wu T.M.Li Y.C.Xu Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqiXinjiang 830011China University of Chinese Academy of Sciences Chinese Academy of SciencesBeijing 100049China Key Laboratory of Particle Astrophysics Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Institut fur Astronomie und Astrophysik Kepler Center for Astro and Particle PhysicsEberhard Karls UniversitatSand 1D-72076 TübingenGermany

We report spectral and timing analysis of the black hole transient MAXI J1631–479 during the hard intermediate state of its 2019 outburst from the Insight-Hard X-ray Modulation Telescope(Insight-HXMT)observations.We find that the energy dependence of the type-C quasi-periodic oscillation(QPO)frequency evolves with time:during the initial rise of a small flare(~MJD 58526.0-58527.1),the QPO frequency increases with increasing energy from~1 to~100 ke V,and then the frequency remains constant after MJD 58527.1.We discover a possible new phenomenon of Fe line’s QPO frequency jump that has never been observed for other black hole transients:during the small flare,the QPO frequency around the Fe line energy is higher than any other energy band,with the frequency difference Δf=0.25±0.08 Hz between 5.5–7.5 ke V and other energy bands.The spectral analysis shows that the evolution of QPOs is related to the equivalent width of the narrow Fe line,and its equivalent width increases during this small flare.We propose that the QPO frequency difference results from the differential precession of a vertically extended jet,and the higher QPO frequency of Fe line could be caused by the layered jet when the jet scale increases.At the same time,the evolution of QPOs is related to the accretion rate,while the energy dependence of QPOs supports the existence of deceleration in the vertically distributed jet.

关键词： accretion accretion disks stars:black holes X-rays:binaries

Effect of relative humidity on the desulfurization performance of calcium-based desulfurizer

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Journal of Environmental Sciences 2024年第4期138卷 179-188页

作者： Juan Lǖ yu fu Haiyan yu HuanWang Zhe Wang Haiyan Chen School of Environment and Resource Southwest University of Science and TechnologyMianyang 621010China Guangyuan Emergency Management bureau Guangyuan 628000China

Low desulfurization efficiency impedes the wide application of dry desulfurization technology,which is a low-cost and simple process,and one significant solution is the development and manufacture of high-performance desulfurizers.In this study,firstly,a steam jet mill was used to digest quicklime;then,we utilized numerical simulation to study the flow field distribution and analyze the driving factors of quicklime digestion;and lastly,the desulfurization performance of the desulfurizer was evaluated under different relative humidities.The results show that the desulfurizer prepared via the steam jet mill had better apparent activity than traditional desulfurizers.Also,the entire jet flow field of the steam jet mill is in a supersonic and highly turbulent flow state,with high crushing intensity and good particle acceleration performance.Sufficient contact with the nascent surface maximizes the formation of slaked lime.The experiments demonstrated that the operating time with 100%desulfurization efficiency and the“break-through”time for the desulfurizer prepared via the steam jet mill is longer than that of traditional desulfurizers,and has significant advantages,especially at low flue gas relative humidity.Compared with traditional desulfurizers,the desulfurizer prepared via steam jet mill expands the range of acceptable flue gas temperature,and the failure temperature is 1.625 times that of traditional desulfurizers.This work breaks through the technical bottleneck of low dry desulfurization efficiency,which is an important step in pushing forward the application of dry desulfurization.

关键词： Dry desulfurization Relative humidity Desulfurization efficiency High-efficiency desulfurizer Quicklime digestion

New speckle pattern interferometry for precise in situ deformation measurements

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Chinese Optics Letters 2024年第1期22卷 34-40页

作者：章如月 yu fu 缪泓 CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei 230027China Shenzhen Key Laboratory of Intelligent Optical Measurement and Detection College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

A new electronic speckle pattern interferometry method is proposed to realize in situ deformation measurements.The feature of the method is the combination of a high-speed camera and multiple laser Doppler vibrometers(LDVs)for synchronous measurements.The high-speed camera is used to record and select effective interferograms,while the LDVs are used to measure the rigid body displacement caused by vibrations.A series of effective interferograms with known shifted phase values are obtained to calculate the deformation phase.The experimental results show that the method performs well in measuring static and dynamic deformations with high accuracy in vibrating environments.

关键词： speckle pattern interferometry laser Doppler vibrometers in situ deformation measurements

Immunomodulatory function of Pien Tze Huang in T Cell-Mediated Anti-tumor Activity against B16-F10,MC38 and Hep1-6 Tumor Models

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Chinese Journal of Integrative Medicine 2024年第4期30卷 348-358页

作者： fu yu-bing LIU Chen-feng WANG Jin-jia JI Xiao-lin TANG Rong-han LIAO Kun-yu CHEN Ling-yue HONG Ya-zhen FAN Bin-bin WANG Shi-cong LIU Wen-Hsien State Key Laboratory of Cellular Stress Biology School of Life SciencesFaculty of Medicine and Life ScienceXiamen UniversityXiamenFujian Province(361102)China fujian Pien Tze Huang Enterprise Key Laboratory of Natural Medicine Research and Development ZhangzhouFujian Province(363000)China

Objective To investigate the anti-tumor effects of Pien Tze Huang(PZH)in mouse models of B16–F10 melanoma,MC38 colorectal cancer,Hep1-6 hepatocellular carcinoma and chemically induced hepatocellular carcinoma model.Methods Various tumor models,including B16–F10,MC38 and Hep1-6 tumor hypodermic inoculation models,B16–F10 and Hep1-6 pulmonary metastasis models,Hep1-6 orthotopic implantation model,and chemically induced hepatocellular carcinoma model,were utilized to evaluate the anti-tumor function of PZH.Tumor growth was assessed by measuring tumor size and weight of solid tumors isolated from C57BL/6 mice.For cell proliferation and death of tumor cells in vitro,as well as T cell activation markers,cytokine production and immune checkpoints analysis,single-cell suspensions were prepared from mouse spleen,lymph nodes,and tumors after PZH treatment.Results PZH demonstrated significant therapeutic efficacy in inhibiting tumor growth(P0.05).Nevertheless,PZH exhibited a remarkable ability to enhance T cell activation and the production of interferon gamma,tumor necrosis factor alpha,and interleukin 2 in CD4^(+)T cells in vitro(Pfunction of PZH in T cell-mediated anti-tumor immunity,indicating that PZH holds promise as a potential therapeutic agent for cancer treatment.

关键词： Pien Tze Huang metastasis anti-tumor immunity T cell activation T cell exhaustion immune checkpoints Chinese medicine

Protective Effects of Danmu Extract Syrup on Acute Lung Injury Induced by Lipopolysaccharide in Mice through Endothelial Barrier Repair

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Chinese Journal of Integrative Medicine 2024年第3期30卷 243-250页

作者： XU Han XU Si-cong LI Li-yan WU yu-huang TAN Yin-feng CHEN Long LIU Pei LIANG Chang-fu HE Xiao-ning LI Yong-hui Hainan Provincial Key Lab of Research&Development on Tropic Herbs Hainan Medical UniversityHaikou571199China Department of Stomatology the Second Affiliated Hospital of Hainan Medical UniversityHaikou571199China

Objective:To investigate the effects of Danmu Extract Syrup(DMS) on lipopolysaccharide(LPS)-induced acute lung injury(ALI) in mice and explore the mechanism.Methods:Seventy-two male Balb/C mice were randomly divided into 6 groups according to a random number table(n=12),including control(normal saline),LPS(5 mg/kg),LPS+DMS 2.5 mL/kg,LPS+DMS 5 mL/kg,LPS+DMS 10 mL/kg,and LPS+Dexamethasone(DXM,5 mg/kg) groups.After pretreatment with DMS and DXM,the ALI mice model was induced by LPS,and the bronchoalveolar lavage fluid(BALF) were collected to determine protein concentration,cell counts and inflammatory cytokines.The lung tissues of mice were stained with hematoxylin-eosin,and the wet/dry weight ratio(W/D) of lung tissue was calculated.The levels of tumor necrosis factor-α(TNF-α),interleukin(IL)-6 and IL-1βin BALF of mice were detected by enzyme linked immunosorbent assay.The expression levels of Claudin-5,vascular endothelial(VE)-cadherin,vascular endothelial growth factor(VEGF),phospho-protein kinase B(p-Akt) and Akt were detected by Western blot analysis.Results:DMS pre-treatment significantly ameliorated lung histopathological changes.Compared with the LPS group,the W/D ratio and protein contents in BALF were obviously reduced after DMS pretreatment(P<0.05 or P<0.01).The number of cells in BALF and myeloperoxidase(MPO) activity decreased significantly after DMS pretreatment(P<0.05 or P<0.01).DMS pre-treatment decreased the levels of TNF-α,IL-6 and IL-1β(P<0.01).Meanwhile,DMS activated the phosphoinositide 3-kinase/protein kinase B(PI3K/Akt) pathway and reversed the expressions of Claudin-5,VE-cadherin and VEGF(P<0.01).Conclusions:DMS attenuated LPS-induced ALI in mice through repairing endothelial barrier.It might be a potential therapeutic drug for LPS-induced lung injury.

关键词： Danmu Extract Syrup acute lung injury inflammatory factors vascular endothelial growth factor phosphoinositide 3-kinase/protein kinase B Chinese medicine Nauclea officinalis

Linear paired electrolysis of furfural to furoic acid at both anode and cathode in a multiple redox mediated system

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Green Energy & Environment 2024年第1期9卷 104-113页

作者： Xinxin Li Linchuan cong Haibo Lin Fangbing Liu Xiangxue fu Hai-Chao Xu Nan Lin State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130012JilinChina State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina

Implementing a new energy-saving electrochemical synthesis system with high commercial value is a strategy of the sustainable development for upgrading the bulk chemicals preparation technology in the future.Here,we report a multiple redox-mediated linear paired electrolysis system,combining the hydrogen peroxide mediated cathode process with the I2 mediated anode process,and realize the conversion of furfural to furoic acid in both side of the dividedﬂow cell simultaneously.By reasonably controlling the cathode potential,the undesired water splitting reaction and furfural reduction side reactions are avoided.Under the galvanostatic electrolysis,the two-mediated electrode processes have good compatibility,which reduce the energy consumption by about 22%while improving the electronic efﬁciency by about 125%.This system provides a green electrochemical synthesis route with commercial prospects.

关键词： Multiple redox mediated system Linear paired electrolysis furfural furoic acid

Evolution of copper species during heat treatment and its effect on CO oxidation reaction on CuCeZrO_(y) catalyst synthesized by a facile solvent-free route

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Journal of Rare Earths 2024年第4期42卷 660-667页

作者： Guangying fu Dongsen Mao Jun yu Qiangsheng Guo School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai21418 China The ZeoMat Group Qingdao Institute of Bioenergy and Bioprocess TechnologyCASQingdao26611China

Several ternary oxides CuCeZrO_(y)(CCZ)were synthesized by a facile grinding method followed by calcination at high temperatures,and used as catalysts for CO oxidation at low temperatures.The influences of calcination temperature(400-600℃)on the physicochemical properties of the assynthesized ternary oxides were investigated by thermogravimetric analysis/differential scanning calorimetry(TGA/DSC),X-ray diffraction(XRD),transmission electron microscopy(TEM),Raman,inductively coupled plasma-optical emission spectrometry(ICP-OES),N_(2) adsorption,H_(2)-temperature programmed reduction(H_(2)-TPR),and X-ray photoelectron spectroscopy(XPS)characterizations.The results show that the increase in calcination temperature from 400 to 500℃is conducive to the high dispersion of CuOx on catalyst surface and the incorporation of Cu species into the support to form the Cu-Ce-Zr-O solid solution.further raising of calcination temperature from 500 to 600℃,however,leads to the segregation of Cu species from the solid solution to aggregate on support surface and growth of highly dispersed CuOx nanoparticles.The highest catalytic activity is acquired over the CCZ calcined at 500℃,which can be ascribed to the largest contents of Cu+species and oxygen vacancies owing to the formation of the maximum amount of Cu-Ce-Zr-O solid solution.

关键词： CuCeZrO_(y)catalyst co oxidation Calcination temperature Grinding method Oxalate precursor Rare earths

Multi-physical fields distribution in billet during helical electromagnetic stirring:A numerical simulation research

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China Foundry 2024年第1期21卷 51-59页

作者： Dong Pan Qing-tao Guo Kai-lun Zhang fu-zhi yu yu-ying Li yu-bao Xiao State Key Laboratory of Metal Materials for Marine Equipment and Application Anshan 114009LiaoningChina Ansteel Beijing Research Institute Co. Ltd.Beijing 102200China

Electromagnetic stirring is one of the widely applied techniques to modify the quality of casting billets.Different from conventional rotate stirring,the helical stirring is more professional in assisting multi-dimensional flow of molten metal and eliminating solidification defects.In this study,the single-winding helical stirring(SWHS)was introduced,offering advantages such as smaller volume and lower electromagnetic shielding compared to traditional helical stirring methods.Following a comprehensive numerical simulation,the stirring parameters of SWHS were adjusted to yoke inclination angle of 43°and frequency of 12 Hz.The higher electromagnetic force and flow velocity in drawing direction,as well as the lower temperature gradient induced by the SWHS,are positive factors for homogeneous solidification of billet.The experimental results on Al-8%Si alloy and 0.4%C-1.1%Mn steel demonstrate that compared to rotate stirring,the SWHS process can induce better billet quality and is more effective in accelerating the equiaxed expansion and reducing element segregation.The SWHS process can enhance the equiaxed ratio of the billet by 58.3%and reduce segregation degree of carbon element by 10.97%.Consequently,SWHS holds great promise as a potential approach for improving the quality of continuous casting billets.

关键词： billet electromagnetic stirring helical solidification element segregation numerical simulation