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氟盐冷却高温堆精细中子通量密度分布计算方法研究

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原子能科学技术 2017年第10期51卷 1749-1755页

作者：杨璞邹杨严睿周波戴叶于世和冀锐敏中国科学院上海应用物理研究所上海201800 中国科学院大学北京100049

氟盐冷却高温堆(FHR)作为第4代核能系统,对安全性和经济性更加注重。FHR全空间中子通量密度的精细分布数据对于材料构件的辐照损伤计算、放射性源项分析以及辐射屏蔽设计等均有重要意义。针对这一需求,本文采用离散纵标(SN)方法为蒙特卡... 详细信息

氟盐冷却高温堆(FHR)作为第4代核能系统,对安全性和经济性更加注重。FHR全空间中子通量密度的精细分布数据对于材料构件的辐照损伤计算、放射性源项分析以及辐射屏蔽设计等均有重要意义。针对这一需求,本文采用离散纵标(SN)方法为蒙特卡罗(MC)方法偏倚计算提供所需的源偏倚和权窗参数,使蒙特卡罗粒子均匀地分布于整个计算模型空间,从而有效降低中子通量密度分布计算的统计误差。在该方法的基础上,编写了耦合程序SN2MCNP,并使用该程序对FHR全空间的中子通量密度分布进行了精细计算。经对比验证,在同样的计算时间和统计方法的要求下,单独使用MCNP计算的结果中,只有30.1%的相对误差达到要求(<10%),而使用SN2MCNP的计算结果中则有99.6%的相对误差达到要求(<10%)。

关键词：氟盐冷却高温堆耦合方法 DENOVO MCNP 中子通量密度共轭中子通量密度

Stability and Stabilization of Sampled-Data Based LFC for Power Systems:A Data-Driven Method

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IEEE/CAA Journal of Automatica Sinica 2025年第1期 291-293页

作者： yu-Long Fan Chuan-Ke Zhang Yong he the School of Automation China University of Geosciences the Hubei Key Laboratory of Advanced Control and Intelligent Automation for Complex Systems the Engineering Research Center of Intelligent Technology for Geo-Exploration Ministry of Education IEEE

Dear Editor,This letter is concerned with stability analysis and stabilization design for sampled-data based load frequency control(LFC) systems via a data-driven method. By describing the dynamic behavior of LFC systems based on a data-based representation, a stability criterion is derived to obtain the admissible maximum sampling interval(MSI) for a given controller and a design condition of the PI-type controller is further developed to meet the required MSI. Finally, the effectiveness of the proposed methods is verified by a case study.

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柳河流域输沙能力探讨

水科学与工程技术 2014年第6期 53-54页

作者：石玉和辽宁省阜新水文局辽宁阜新123000

分析了柳河各个河段及支流含沙量、输沙能力、径流等情况,掌握流域内水土流失状况的分布,探讨流域内的变化规律,为柳河流域的综合治理提供科学依据。

关键词：柳河输沙量水土流失综合治理

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自动测墒仪在阜新地区的应用

黑龙江水利科技 2014年第8期42卷 23-26页

作者：石玉和辽宁省阜新水文局辽宁阜新123000

阜新地区地处中温带半干旱的季风气候区,及时掌握农作物播种期和生长期的土壤墒情变化,对农作物的适时播种、抗旱等起到至关重要的作用。随着社会进步、科学发展,劳动力得到很大程度的解放。移动测墒仪是一种便携式自动测量墒情仪器,通... 详细信息

阜新地区地处中温带半干旱的季风气候区,及时掌握农作物播种期和生长期的土壤墒情变化,对农作物的适时播种、抗旱等起到至关重要的作用。随着社会进步、科学发展,劳动力得到很大程度的解放。移动测墒仪是一种便携式自动测量墒情仪器,通过与人工观测值进行对比分析,误差满足需要,则可建设固定自动测墒站点(原理一样),对土壤墒情进行实时监测,掌握田间土壤墒情变化情况,为防汛抗旱提供科学的可靠依据。

关键词：自动测墒人工观测固定站点对比分析应用

岩溶区地表河不同时期高分辨率监测碳通量变化特征研究——以漓江流域为例

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西南大学学报（自然科学版） 2018年第3期40卷 150-158页

作者：何若雪孙平安于奭何师意国土资源部广西岩溶动力学重点实验室/中国地质科学院岩溶地质研究所广西桂林541004 成都工业学院科技处成都611730

为探讨同一岩溶流域不同时期水体理化性质及无机碳通量的不同特征及其影响因素,本文于2012年5月8日-17日,7月6日-13日,12月3日-10日对漓江流域进行了洪水期、平水期及枯水期的高频率昼夜监测.结果表明,水动力条件是控制研究区水体理化... 详细信息

为探讨同一岩溶流域不同时期水体理化性质及无机碳通量的不同特征及其影响因素,本文于2012年5月8日-17日,7月6日-13日,12月3日-10日对漓江流域进行了洪水期、平水期及枯水期的高频率昼夜监测.结果表明,水动力条件是控制研究区水体理化性质的首要因素,且降雨条件下控制力增强,稀释作用占主导地位,pH值、水温、电导率及离子质量浓度随降雨过程降低;无降雨条件下,水体理化性质主要受温度及水生植物光合作用、呼吸作用控制,表现出明显的昼夜变化特征:水温及pH值白天高、夜晚低,电导率及HCO-3离子质量浓度白天低、夜晚高.碳通量由高到低分别为洪水期(平均4.43kg C/s)、平水期(平均1.51kg C/s)、枯水期(平均1.07kg C/s),受水动力条件及HCO-3离子质量浓度共同控制,其中水动力条件占主导地位,但二者同时发生变化时,碳通量则随变异系数较大的一方波动.

关键词：漓江碳通量高分辨率监测

Preparation of Co/S co-doped carbon catalysts for excellent methylene blue degradation

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 169-181页

作者： Haixu Li Haobo he Tiannan Jiang yunfei Du Zhichen Wu Liang Xu Xinjie Wang Xiaoguang Liu Wanhua yu Wendong Xue School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Beijing Jinyu Tongda Refractory Technologies Co. Ltd.Beijing 100085China

S and Co co-doped carbon catalysts were prepared via pyrolysis of MOF-71 and thiourea mixtures at 800℃at a mass ratio of MOF-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PMS)for methylene blue(MB)*** effects of two different mixing routes were identified on the MB degradation ***,the catalyst obtained by the alcohol solvent evaporation(MOF-AEP)mixing route could degrade 95.60%MB(50 mg/L)within 4 min(degradation rate:K=0.78 min^(-1)),which was faster than that derived from the direct grinding method(MOF-DGP,80.97%,K=0.39 min^(-1)).X-ray photoelectron spectroscopy revealed that the Co-S content of MOF-AEP(43.39at%)was less than that of MOF-DGP(54.73at%),and the proportion of C-S-C in MOF-AEP(13.56at%)was higher than that of MOF-DGP(10.67at%).Density functional theory calculations revealed that the adsorption energy of Co for PMS was -2.94 eV when sulfur was doped as C-S-C on the carbon skeleton,which was higher than that when sulfur was doped next to cobalt in the form of Co-S bond(-2.86 eV).Thus,the C-S-C sites might provide more contributions to activate PMS compared with ***,the degradation parameters,including pH and MOF-AEP dosage,were ***,radical quenching experiments and electron paramagnetic resonance(EPR)measurements revealed that ^(1)O_(2)might be the primary catalytic species,whereas·O~(2-)might be the secondary one in degrading MB.

关键词： advanced oxidation process alcohol solvent evaporation hydrogen bond S and Co co-doped carbon catalysts wastewater remediation

T cell interactions with microglia in immune-inflammatory processes of ischemic stroke

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Neural Regeneration Research 2025年第5期20卷 1277-1292页

作者： yuxiao Zheng Zilin Ren Ying Liu Juntang Yan Congai Chen Yanhui he yuyu shi Fafeng Cheng Qingguo Wang Changxiang Li Xueqian Wang School of Traditional Chinese Medicine Beijing University of Chinese MedicineBeijingChina Library Beijing University of Chinese MedicineBeijingChina Dongzhimen Hospital Beijing University of Chinese MedicineBeijingChina

The primary mechanism of secondary injury after cerebral ischemia may be the brain inflammation that emerges after an ischemic stroke,which promotes neuronal death and inhibits nerve tissue *** the first immune cells to be activated after an ischemic stroke,microglia play an important immunomodulatory role in the progression of the *** an ischemic stroke,peripheral blood immune cells(mainly T cells)are recruited to the central nervous system by chemokines secreted by immune cells in the brain,where they interact with central nervous system cells(mainly microglia)to trigger a secondary neuroimmune *** review summarizes the interactions between T cells and microglia in the immune-inflammatory processes of ischemic *** found that,during ischemic stroke,T cells and microglia demonstrate a more pronounced synergistic ***1,Th17,and M1 microglia can co-secrete proinflammatory factors,such as interferon-γ,tumor necrosis factor-α,and interleukin-1β,to promote neuroinflammation and exacerbate brain ***2,Treg,and M2 microglia jointly secrete anti-inflammatory factors,such as interleukin-4,interleukin-10,and transforming growth factor-β,to inhibit the progression of neuroinflammation,as well as growth factors such as brain-derived neurotrophic factor to promote nerve regeneration and repair brain *** interactions between microglia and T cells influence the direction of the subsequent neuroinflammation,which in turn determines the prognosis of ischemic stroke *** trials have been conducted on the ways to modulate the interactions between T cells and microglia toward anti-inflammatory communication using the immunosuppressant fingolimod or overdosing with Treg cells to promote neural tissue repair and reduce the damage caused by ischemic ***,such studies have been relatively infrequent,and clinical experience is still *** summary,in ischemic stroke,T cell subsets and activated micro

关键词： brain immune inflammation interaction ischemic stroke mechanism microglia neuron secondary injury T cells

Direct Photolithography of WO_(x)Nanoparticles for High‑Resolution Non‑Emissive Displays

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Nano-Micro Letters 2025年第3期17卷 297-309页

作者： Chang Gu Guojian Yang Wenxuan Wang Aiyan shi Wenjuan Fang Lei Qian Xiaofei Hu Ting Zhang Chaoyu Xiang yu‑Mo Zhang Laboratory of Optoelectronic Information Technology and Devices Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201People’s Republic of China Hangzhou Bay Laboratory of Advanced Nano‑Optoelectronic Materials and Devices Qianwan Institute of CNITECHNingbo 315336People’s Republic of China Smart Materials for Architecture Research Lab Innovation Center of Yangtze River DeltaZhejiang UniversityJiaxing 314100People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China State Key Lab of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012People’s Republic of China

High-resolution non-emissive displays based on electrochromic tungsten oxides(WOx)are crucial for future near-eye virtual/augmented reality interactions,given their impressive attributes such as high environmental stability,ideal outdoor readability,and low energy ***,the limited intrinsic structure of inorganic materials has presented a significant challenge in achieving precise patterning/pixelation at the micron ***,we successfully developed the direct photolithography for WOx nanoparticles based on in situ photo-induced ligand *** strategy enabled us to achieve ultra-high resolution efficiently(line widthhe best resolution for reported inorganic electrochromic materials).Additionally,the resulting device exhibited impressive electrochromic performance,such as fast response(3600 cycles),as well as promising applications in electronic logos,pixelated displays,flexible electronics,*** success and advancements presented here are expected to inspire and accelerate research and development(R&D)in high-resolution non-emissive displays and other ultra-fine micro-electronics.

关键词： Electrochromic Direct photolithography WOx nanoparticles In situ photo-induced ligand exchange High-resolution displays

Transient chemical-mediated epigenetic modulation confers unrestricted lineage potential on human primed pluripotent stem cells

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Science China Life Sciences 2025年

作者： shi Chen yuanyuan he Lejun Lv Bei Liu Cheng Li Hongkui Deng Jun Xu Department of Cell Biology School of Basic Medical Sciences Peking University Stem Cell Research Center Peking University Health Science Center Peking University Academy of Advanced Interdisciplinary Studies Peking University BeiCell Therapeutics School of Life Sciences Center for Bioinformatics Center for Statistical Science Peking University MOE Engineering Research Center of Regenerative Medicine School of Basic Medical Sciences State Key Laboratory of Natural and Biomimetic Drugs Peking University Health Science Center and the MOE Key Laboratory of Cell Proliferation and Differentiation College of Life Sciences Peking-Tsinghua Center for Life Sciences Peking University

Human primed pluripotent stem cells are capable of generating all the embryonic ***,their extraembryonic trophectoderm potentials are *** remains unclear how to expand their developmental potential to trophectoderm *** we show that transient treatment with a cocktail of small molecule epigenetic modulators imparts trophectoderm lineage potentials to human primed pluripotent stem cells while preserving their embryonic *** chemically treated cells can generate trophectoderm-like cells and downstream trophoblast stem cells,diverging into syncytiotrophoblast and extravillous trophoblast *** and CUT&Tag analyses reveal that these induced cells share transcriptional profiles with in vivo trophectoderm and cytotrophoblast,and exhibit reduced H3K27me3 modification at gene loci specific to trophoblast lineages compared with primed pluripotent *** exploration highlighted the critical roles of epigenetic modulators HDAC2,EZH1/2,and KDM5s in the activation of trophoblast lineage *** findings demonstrate that transient epigenetic resetting activates unrestricted lineage potential in human primed pluripotent stem cells,and offer new mechanistic insights into human trophoblast lineage specification and in vitro models for studying placental development and related disorders.

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