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Axisymmetric Waves in Isothermal Accretion Discs with Vertical Self-Gravity

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Communications in Theoretical Physics 2001年第12期36卷 743-748页

作者： liu Xiao-ci YANG Lan-Tian WU Shao-Ping DING Shi-Xue Department of Physics Hainan Normal College Haikou 571158 Hainan Province Chinat Department of Physics and Institute of Astrophysics Huazhong Normal University Wuhan 430079 China Department of Physics and Institute of Astrophysics Huazhong Normal University Wuhan 430079 China Department of Physics and Institute of Astrophysics Huazhong Normal University Wuhan 430079 China Department of Physics and Institute of Astrophysics Huazhong Normal University Wuhan 430079 China Department of Physics Xiangfan Normal College Xiangfan 441053 Hubei Province China

We extend the research of axisymmetric waves in accretion discs with three-dimensional structure to the case that vertical self-gravity of the discs is included. We derive and analyze the dispersion relation and solve the eigenfunctions numerically. The following results have been reached: vertical self-gravity expands the forbidden region of the wave propagation. As the influence of the vertical self-gravity increases, the group velocities of the waves get smaller and the vertical nodes of the wave shrink to the middle plane of the disc.

关键词： accretion, accretion discs, hydrodynamics, waves

Wave Propagation in Accretion Disks with Self-Gravity

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Chinese Physics Letters 2001年第2期18卷 301-303页

作者： liu Xiao-ci YANG Lan-Tian WU Shao-Ping DING Shi-Xue Department of Physics and Institute of AstrophysicsHuazhong Normal UniversityWuhan 430079 Department of Physics Hainan Normal CollegeHaikou 571158 Department of Physics Xiangfan Normal CollegeXiangfan 441053

We extend the research by Lubow and Pringle of axisymmetric waves in accretion disks to the case where self-gravity of disks should be *** derive and analyse the dispersion relations with the effect of *** show that self-gravity extends the forbidden region of the wave propagation:for high frequency p-modes,self-gravity makes the wavelength shorter and the group velocity larger;for low frequency g-modes,the effect is opposite.

关键词： accretion effect shorter

Imbalance of circulating Follicular Regulatory and Follicular Helper T Cell Subpopulations Is Associated with Disease Progression and Serum CYFRA 21-1 Levels in Patients with Non-small Cell Lung Cancer

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Current Medical Science 2024年第1期44卷 102-109页

作者： Tian-ci liu Mo-han ZHENG Xing-yue ZENG Rui KANG Ayibaota Bahabayi Bulidierxin Tuerhanbayi Song-song LU Chen liu Department of Clinical Laboratory Peking University People's HospitalBeijing 100044China School of Basic Medical Sciences Peking University Health Science CenterBeijing 100191China

Objective This study aimed to investigate the changes of follicular helper T(TFH)and follicular regulatory T(TFR)cell subpopulations in patients with non-small cell lung cancer(NSCLC)and their *** Peripheral blood was collected from 58 NSCLC patients at different stages and 38 healthy *** cytometry was used to detect TFH cell subpopulation based on programmed death 1(PD-1)and inducible co-stimulator(ICOS),and TFR cell subpopulation based on cluster determinant 45RA(CD45RA)and forkhead box protein P3(FoxP3).The levels of interleukin-10(IL-10),interleukin-17a(IL-17a),interleukin-21(IL-21),and transforming growth factor-β(TGF-β)in the plasma were measured,and changes in circulating B cell subsets and plasma IgG levels were also *** correlation between serum cytokeratin fragment antigen 21-1(CYFRA 21-1)levels and TFH,TFR,or B cell subpopulations was further *** The TFR/TFH ratio increased significantly in NSCLC *** CD45RA^(+)FoxP3^(int) TFR subsets were increased,with their proportions increasing in stages Ⅱ to Ⅲ and decreasing in stage ***-1^(+)ICOS+TFH cells showed a downward trend with increasing *** IL-21 and TGF-β concentrations were increased in NSCLC patients compared with healthy ***,plasma IgG levels,and CD45RA^(+)FoxP3^(int) TFR cells showed similar *** numbers and plasmablasts were positively correlated with CYFRA 21-1 in stages Ⅰ-Ⅲ and negatively correlated with CYFRA 21-1 in stage *** circulating TFH and TFR cell subpopulations and plasmablasts dynamically change in different stages of NSCLC,which is associated with serum CYFRA 21-1 levels and reflects disease progression.

关键词： non-small cell lung cancer follicular helper T cells follicular regulatory T cells progression

Pollution source identification methods and remediation technologies of groundwater: A review

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China Geology 2024年第1期7卷 125-137页

作者： Ya-ci liu Yu-hong Fei Ya-song Li Xi-lin Bao Peng-wei Zhang Fujian Provincial Key Laboratory of Water Cycling and Eco-Geological Processes Institute of Hydrogeology and Environmental GeologyChinese Academy of Geological SciencesXiamen 361000China Key Laboratory of Water and Soil Resources Conservation and Restoration in the Middle and Lower Reaches of Yellow River Basin MNRZhengzhou 450016China

Groundwater is an important source of drinking *** pollution severely endangers drinking water safety and sustainable social *** the case of groundwater pollution,the top priority is to identify pollution sources,and accurate information on pollution sources is the premise of efficient ***,an appropriate pollution remediation scheme should be developed according to information on pollution sources,site conditions,and economic *** methods for identifying pollution sources mainly include geophysical exploration,geochemistry,isotopic tracing,and numerical *** these identification methods,only the numerical modeling can recognize various information on pollution sources,while other methods can only identify a certain aspect of pollution *** remediation technologies of groundwater can be divided into in-situ and ex-situ remediation technologies according to the remediation *** in-situ remediation technologies enjoy low costs and a wide remediation range,but their remediation performance is prone to be affected by environmental conditions and cause secondary *** ex-situ remediation technologies boast high remediation efficiency,high processing capacity,and high treatment concentration but suffer high *** methods for pollution source identification and remediation technologies are applicable to different *** achieve the expected identification and remediation results,it is feasible to combine several methods and technologies according to the actual hydrogeological conditions of contaminated sites and the nature of ***,detailed knowledge about the hydrogeological conditions and stratigraphic structure of the contaminated site is the basis of all work regardless of the adopted identification methods or remediation technologies.

关键词： Groundwater pollution Identification of pollution sources Geophysical exploration identification Geochemistry identification Isotopic tracing Numerical modeling Remediation technology Hydrogeological conditions Hydrogeological survey engineering

Dark Matter Search in Dwarf Irregular Galaxies with Ten Years of Data from the Ice Cube Neutrino Observatory

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Research in Astronomy and Astrophysics 2024年第3期24卷 75-82页

作者： Yi-Fei Lü Ben-Yang Zhu Rong-Lan Li Xue-Kang Guo Tian-ci liu Yong-Bo Huang Yun-Feng Liang Guangxi Key Laboratory for Relativistic AstrophysicsSchool of Physical Science and TechnologyGuangxi University Nanning 530004China

Dwarf irregular galaxies(dIrrs),as rotationally supported systems,have more reliable J-factor measurements than dwarf spheroidal galaxies and have received attention as targets for dark matter detection in recent *** this paper,we use 10 yr of IceCube muon-track data and an unbinned maximum-likelihood-ratio method to search for neutrino signals beyond the background from the directions of seven dIrrs,aiming to detect neutrinos produced by heavy annihilation dark *** do not detect any significant *** on such null results,we calculate the upper limits on the velocity-averaged annihilation cross section for 1 TeV–10 PeV dark *** limits,although weaker than the strictest constraints in the literature in this mass range,are also a good complement to the existing results considering the more reliable J-factor measurements of dIrrs.

关键词： (cosmology) dark matter-cosmology theory-galaxies dwarf

Characteristics and sources of microplastic pollution in the water and sediments of the Jinjiang River Basin,Fujian Province,China

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China Geology 2022年第3期5卷 429-438页

作者： Ya-ci liu Lin Wu Guo-wei Shi Sheng-wei Cao Ya-song Li Institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesChina Geological SurveyMinistry of Natural ResourcesShijiazhuang 050061China Fujian Provincial Key Laboratory of Water Cycling and Eco-Geological Processes Xiamen 361000China

Microplastic pollution is widely distributed from surface water to sediments to groundwater vertically and from land to the ocean *** study collected samples from surface water,groundwater,and sediments from upper to lower reaches and then to the estuary in 16 typical areas in the Jinjiang River Basin,Fujian Province,***,it determined the components and abundance of the microplastics and analyzed the possible microplastic sources through principal component analysis(PCA).As a result,seven main components of microplastics were detected,i.e.,polyethylene(PE),polypropylene(PP),polyvinyl chloride(PVC),polyethylene terephthalate(PET),polyformaldehyde(POM),nylon 6(PA6),and polystyrene(PS).Among them,PE and PP were found to have the highest proportion in the surface water and sediments and in the groundwater,*** surface water,groundwater,and sediments had average microplastic abundance of 1.6 n/L,2.7 n/L and 33.8 n/kg,*** microplastics in the sediments had the largest particle size,while those in the groundwater had the smallest particle *** with water bodies and sediments in other areas,those in the study area generally have medium-low-level microplastic *** pollution sources were determined according to PCA,i.e.,the dominant agriculture-forestry-fishery source,domestic wastewater,and industrial *** study can provide a scientific basis for the control of microplastics in rivers.

关键词： Microplastic Surface water Groundwater Sediment Estuary Hydrogeological survey engineering Environment geological survey engineering Jinjiang River basin

Carbon emissions in China’s steel industry from a life cycle perspective:Carbon footprint insights

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Journal of Environmental Sciences 2025年第2期148卷 650-664页

作者： Xiaocong Song Shuai Du Chenning Deng Peng Shen Minghui Xie ci Zhao Chen Chen Xiaoyu liu State Key Laboratory of Environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012China Beijing Key Laboratory of Water Resources&Environmental Engineering China University of Geosciences(Beijing)Beijing 100083China Chinese Research Academy of Environmental Sciences Environmental Technology&Engineering Co.Ltd. Beijing 100012China

China is the most important steel producer in the world,and its steel industry is one of themost carbon-intensive industries in ***,research on carbon emissions from the steel industry is crucial for China to achieve carbon neutrality and meet its sustainable global development *** constructed a carbon dioxide(CO_(2))emission model for China’s iron and steel industry froma life cycle perspective,conducted an empirical analysis based on data from2019,and calculated the CO_(2)emissions of the industry throughout its life *** emission reduction factors were identified using sensitivity *** results demonstrated that the CO_(2)emission intensity of the steel industry was 2.33 ton CO_(2)/ton,and the production and manufacturing stages were the main sources of CO_(2)emissions,accounting for 89.84%of the total steel life-cycle ***,fossil fuel combustion had the highest sensitivity to steel CO_(2)emissions,with a sensitivity coefficient of 0.68,reducing the amount of fossil fuel combustion by 20%and carbon emissions by 13.60%.The sensitivities of power structure optimization and scrap consumption were similar,while that of the transportation structure adjustment was the lowest,with a sensitivity coefficient of less than *** the current strategic goals of peak carbon and carbon neutrality,it is in the best interest of the Chinese government to actively promote energy-saving and low-carbon technologies,increase the ratio of scrap steel to steelmaking,and build a new power system.

关键词： Iron and steel industry Life cycle Carbon dioxide(CO_(2))emissions Carbon footprint China

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p53蛋白质C端的三维结构及生物功能区

生物化学与生物物理进展 1999年第3期26卷 264-270页

作者：张彦刘次全昆明医学院生物教研室中国科学院昆明动物研究所

利用ｐ５３Ｃ端１１８个氨基酸的ｍＲＮＡ二级结构和ＣｈｏｕＦａｓｍａｎ蛋白质二级结构预测原则，预测ｐ５３蛋白质Ｃ端２８９～３２５为卷曲肽段，３６８～３９３段包括两段螺旋结构：α１３６８～３７３，α２３８１～３８８．其... 详细信息

利用ｐ５３Ｃ端１１８个氨基酸的ｍＲＮＡ二级结构和ＣｈｏｕＦａｓｍａｎ蛋白质二级结构预测原则，预测ｐ５３蛋白质Ｃ端２８９～３２５为卷曲肽段，３６８～３９３段包括两段螺旋结构：α１３６８～３７３，α２３８１～３８８．其中三段已知的蛋白质二级结构与此ｍＲＮＡ二级结构单元间有准确的对应关系．与四种以多重序列联配为基础的蛋白质二级结构预测方法（准确率均为７３２０％左右）相对照，预测结果基本一致．结合单体聚合区３１个氨基酸晶体结构，在ＳＧＩＩＮＤＩＧＯ２工作站上构建了ｐ５３Ｃ端１０８个残基的三维结构．进一步揭示了ｐ５３Ｃ端诸多生物功能区之间的空间构象关系．

关键词： p53蛋白二级结构 C端三维结构生物功能区

抑制启动子的三链DNA的结构模建及稳定性研究

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生物化学与生物物理进展 2000年第3期27卷 283-286页

作者：杨洁刘次全 *** 中国科学院昆明动物研究所昆明650223

在IRISIndigo2 (SGI公司 )工作站上 ,利用InsightⅡ /MSI软件包 ,以TAT三链DNA为模板 ,采用同源模建的方法 ,分别建立起两个含 2 1nt的脱氧寡核苷酸CP1(G3TG2TGT2G5TG2TGT )和CP3(TGTG2TG5T2GTG2TG3)的三维结构 .采用分子力学方法进行... 详细信息

在IRISIndigo2 (SGI公司 )工作站上 ,利用InsightⅡ /MSI软件包 ,以TAT三链DNA为模板 ,采用同源模建的方法 ,分别建立起两个含 2 1nt的脱氧寡核苷酸CP1(G3TG2TGT2G5TG2TGT )和CP3(TGTG2TG5T2GTG2TG3)的三维结构 .采用分子力学方法进行能量优化 ,将得到的能量最低结构作为分子的优势构象 .研究结果显示 ,CP1的能量低于CP3的能量 ,即前者的结构较后者稳定 .从而证明了CP1与乙肝病毒 (HBV)的核心启动子 (Cp)片段之间能稳定地形成三链DNA ,并能特异性地抑制DNA结合蛋白与Cp片段的结合 .这些结果表明。

关键词：三链DNA 反基因策略同源模建结构稳定性 HBV