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基于COSINE软件包子通道软件的换热模型和氧化关系式适应性研究

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核动力工程 2024年第4期45卷 127-133页

作者：程以炫孟召灿张昊章艺林赵萌杨燕华上海交通大学国家电投智慧能源创新学院上海200240 国家电投集团科学技术研究院有限公司北京102209 上海交通大学核科学与工程学院上海200240

针对压水堆核电子通道软件中换热模型和氧化关系式对提高堆芯安全性和国产化软件模拟预测准确性的急迫需求,采用数值模拟技术在COSINE软件包子通道软件中分析换热模型和氧化关系式,并运用实验数据研究了不同理论关系式对沸腾换热性能和... 详细信息

针对压水堆核电子通道软件中换热模型和氧化关系式对提高堆芯安全性和国产化软件模拟预测准确性的急迫需求,采用数值模拟技术在COSINE软件包子通道软件中分析换热模型和氧化关系式,并运用实验数据研究了不同理论关系式对沸腾换热性能和氧化量的影响。结果表明,该软件具有模拟棒束内临界前后换热模型的能力,其模拟结果和实验值吻合良好。在过热度小于4K前,max模型计算核态沸腾适用性较好;在过热度大于4 K后,PLUS模型适用性较好。Dougall-Rohsenow模型计算膜态沸腾适用性较好。Baker-Juster模型在温度低于1374K前,略微高估氧化量;在温度高于1374K后,低估氧化量。

关键词：子通道 COSINE软件包壁面换热氧化量适应性

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Gd-La-Al合金的微观结构与磁热效应

中国稀土学报 2024年第1期42卷 62-69,I0003页

作者：高磊戴默涵程娟刘翠兰王鹏宇李兆杰包头稀土研究院白云鄂博稀土资源研究与综合利用国家重点实验室内蒙古包头014030

以Gd_(3-x)La_(x)Al_(2)(x=0,0.1,0.2,0.3)磁制冷材料为研究对象,系统分析了合金的相组成、微观组织及磁热性能。结果表明,Gd_(3-x)La_(x)Al_(2)(x=0,0.1,0.2,0.3)合金均由Gd_(3)Al_(2)相、GdAl相、Gd_(2)Al相组成。La原子主要分布于Gd_(2)Al相,且La元素的添加具有调控Gd Al相形貌的作用。对M-T曲线求一阶导数可得,Gd_(3-x)La_(x)Al_(2)(x=0,0.1,0.2,0.3)合金的居里温度T_(C)随La含量的增加呈逐渐降低的趋势,分别为275,267,261,252 K,适用于近室温领域的制冷。利用Landau理论,分析了Gd_(3-x)La_(x)Al_(2)(x=0,0.1,0.2,0.3)合金的磁相变特征。分析拟合结果可知,Gd_(3-x)La_(x)Al_(2)(x=0,0.1,0.2,0.3)合金在居里温度T_(C)附近发生二级磁相变。0~2 T磁场下Gd_(3)Al_(2)合金的最大等温磁熵变(ΔS_(M))^(max)为3.05 J·kg^(-1)·K^(-1),最大绝热温变(ΔT_(ad))^(max)为2.12 K,表现出良好的磁热性能。

关键词：磁制冷材料微观组织磁相变磁热性能稀土

Tropospheric NO_2 vertical column densities retrieved from ground-based max-DOAS measurements at Shangdianzi regional atmospheric background station in China

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环境科学学报：英文版 2019年第6期31卷 186-196页

作者： Siyang cheng Jianzhong Ma Weiping cheng Peng Yan Huaigang Zhou Liyan Zhou Peng Yang State Key Laboratory of Severe Weather & CMA Key Laboratory of Atmospheric Chemistry Chinese Academy of Meteorological Sciences China Waterborne Transport Research Institute CMA Meteorological Observation Centre Shangdianzi Regional Air Background Station Beijing Meteorological Bureau Meteorological Bureau of Shijiazhuang

Ground-basedMulti-AXis Differential Optical Absorption Spectroscopy(max-DOAS)measurements were performed at Shangdianzi(SDZ)regional atmospheric background station in northern China from March 2009 to February *** tropospheric NO_2vertical column densities(VCDs)were retrieved to investigate the background condition of the Beijing–Tianjin–Hebei developed economic circle in *** seasonal variation of mean NO_2tropospheric VCDs(VCD_(Trop))at SDZ is apparent,with the maximum(1.3×10^(16)molec/cm^2)in February and the minimum(3.5×10^(15)molec/cm^2)in August,much lower than those observed at the Beijing city *** average daytime diurnal variations of NO_2VCD_(Trop )are rather consistent for all four seasons,presenting the minimum at noon and the higher values in the morning and *** largest and lowest amplitudes of NO_2VCD_(Trop)diurnal variation appear in winter and in summer,*** diurnal pattern at SDZ station is similar to those at other less polluted stations,but distinct from the ones at the urban or polluted *** NO_2VCDs at SDZ are strongly dependent on the wind,with the higher values being associated with the pollution plumes from Beijing *** NO_2VCDs derived from ground-based max-DOAS at SDZ show to be well correlated with corresponding OMI(Ozone Monitoring Instrument)satellite products with a correlation coefficient R=***,the OMI observations are on average higher than max-DOAS NO_2VCDs by a factor of 28%,probably due to the OMI grid cell partly covering the south of SDZ which is influenced more by the pollution plumes from the urban areas.

关键词： Ground-basedmax-DOAS Tropospheric NO2 Satellite validation Pollution plume Regional atmospheric background station

24小时动态心电图对预激综合征伴心房颤动患者射频消融术后心房颤动复发的预测价值

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中国医药 2024年第10期19卷 1446-1450页

作者：蔡玲成瑶张磊新疆维吾尔自治区喀什地区第一人民医院心电功能科喀什844000 新疆医科大学第四附属医院心血管内科乌鲁木齐830054

目的探讨24 h动态心电图对预激综合征(WPW)伴心房颤动患者射频消融术后心房颤动复发的预测价值。方法选取2021年8月至2023年9月在新疆维吾尔自治区喀什地区第一人民医院心电功能科就诊的WPW伴心房颤动射频消融术后6个月心房颤动复发的患... 详细信息

目的探讨24 h动态心电图对预激综合征(WPW)伴心房颤动患者射频消融术后心房颤动复发的预测价值。方法选取2021年8月至2023年9月在新疆维吾尔自治区喀什地区第一人民医院心电功能科就诊的WPW伴心房颤动射频消融术后6个月心房颤动复发的患者51例(复发组)及51例术后未复发心房颤动患者(未复发组)。比较2组患者术前24 h动态心电图[P波振幅、最大P波时限(P_(max))、P波离散度(Pd)和P波终末电势(Ptf)、PR间期、心率校正后QT间期(QTc)和Tp-Te间期]。采用多因素Logistic回归模型分析WPW伴心房颤动患者射频消融术后心房颤动复发的影响因素,并用受试者工作特征(ROC)曲线分析24 h动态心电图对术后心房颤动复发的预测价值。结果复发组QTc、P波振幅、P_(max)、Pd值高于未复发组,而Ptf则低于未复发组(均Pmax)和Pd值及低LVEF均是WPW伴心房颤动患者射频消融术后心房颤动复发的独立危险因素(均Pmax)、Pd单独预测WPW伴心房颤动患者射频消融术后心房颤动复发的曲线下面积(AUC)为0.809(95%置信区间:0.769~0.838)、0.811(95%置信区间:0.770~0.875),二者联合预测AUC为0.918(95%置信区间:0.878~0.949),联合预测效能较单独预测效能更好(均Pmax)和Pd值是WPW伴心房颤动患者射频消融术后心房颤动复发的危险因素,且二者联合预测术后心房颤动复发的效能较高。

关键词：心房颤动预激综合征 24 h动态心电图射频消融术复发

黄杞总黄酮对心力衰竭大鼠心肌缺血再灌注损伤的保护作用研究

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四川中医 2024年第7期42卷 79-83页

作者：张程廖军华广州中医药大学附属广州中医医院广东广州510000 广州誉嘉生物科技有限公司广东广州510000

目的:探讨黄杞总黄酮对心力衰竭(HF)大鼠心肌缺血再灌注损伤(IRI)的保护作用。方法:60只雄性SD大鼠建模成功后按随机数表法分为5组:假手术组、IRI模型组、低剂量黄杞总黄酮(TFER)组、中剂量TFER组、高剂量TFER组,每组12只,连续灌胃7d。... 详细信息

目的:探讨黄杞总黄酮对心力衰竭(HF)大鼠心肌缺血再灌注损伤(IRI)的保护作用。方法:60只雄性SD大鼠建模成功后按随机数表法分为5组:假手术组、IRI模型组、低剂量黄杞总黄酮(TFER)组、中剂量TFER组、高剂量TFER组,每组12只,连续灌胃7d。使用心电图和超声心动图检测大鼠S-T段波幅、左室短轴缩短率(LVFS)、左室射血分数(LVEF)、左室内压最大上升速率(+dp/dt_(max))、左室内压最大下降速率(-dp/dt_(max)),使用苏木精-伊红(HE)染色法检测大鼠心肌梗死面积百分比,使用Masson染色法检测大鼠心肌胶原附着面积百分比,使用比色法检测超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)、丙二醛(MDA),使用蛋白免疫印迹(Western blot)法检测核因子E2相关因子2(Nrf2)、Kelch样ECH关联蛋白1(Keap1)表达水平。结果:与IRI模型组相比,使用TFER灌胃的IRI大鼠心电图S-T段得到显著修复,心肌梗死面积百分比、胶原附着面积百分比、MDA、Keap1表达显著降低,LVFS、LVEF、+dp/dt_(max)比值、-dp/dt_(max)比值、SOD、GSH-Px、Nrf2表达显著提高,差异均有统计学意义(P<0.05),其中高剂量TFER组上述指标差异最显著(P<0.05)。结论:黄杞总黄酮对HF大鼠IRI有保护作用,其机制可能与减少心肌梗死面积、改善心功能、缓解氧化应激反应有关。

关键词：黄杞总黄酮心力衰竭大鼠心肌缺血再灌注损伤保护作用机制

Magnetism, heat capacity, magnetocaloric effect, and magneto-transport properties of heavy fermion antiferromagnet CeGaSi

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Chinese Physics B 2024年第6期33卷 495-502页

作者：张黎博董庆新白建利刘乔宇程靖雯李存东刘品宇孙英睿黄宇任治安陈根富 Institute of Physics and Beijing National Laboratory for Condensed Matter Physics Chinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Songshan Lake Materials Laboratory Dongguan 523808China

We synthesize high-quality single crystal of CeGaSi by a Ga self-flux method and investigate its physical properties through magnetic susceptibility,specific heat and electrical resistivity measurements as well as high pressure *** measurements reveal that an antiferromagnetic order develops below T_(m)~10.4 K with magnetic moments orientated in the ab *** enhanced electronic specific heat coefficient and the negative logarithmic slope in the resistivity of CeGaSi indicate that the title compound belongs to the family of Kondo system with heavy fermion ground *** max magnetic entropy change-ΔS_(M)^(max)(μ_(0)H⊥c,μ_(0)H=7 T) around T_(m) is found to reach up to 11.85 J·kg^(-1)·K^(-1).Remarkably,both the antiferromagnetic transition temperature and-ln T behavior increase monotonically with pressure applied to 20 kbar(1 bar=10~5 Pa),indicating that much higher pressure will be needed to reach its quantum critical point.

关键词： heavy fermion antiferromagnetic order magnetocaloric effect

参考作物腾发量的时空演变规律及成因分析——以华中华南湿润亚热带地区为例

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长江流域资源与环境 2024年第5期33卷 1110-1121页

作者：邓安妮俞佳固杨晓娟魏英楠刘航铖姚宁西北农林科技大学水利与建筑工程学院陕西杨凌712100 中国农业科学院农业环境与可持续发展研究所北京100081

参考作物腾发量(ET0)是制定灌溉制度的基本参数,更是干旱评价的必要变量。为全面探究华中华南湿润亚热带地区ET0的时空变化规律及其主要成因,基于该地区1961~2020年246个站点的逐日气象资料和部分大气环流指数,采用Penman-Monteith法计... 详细信息

参考作物腾发量(ET0)是制定灌溉制度的基本参数,更是干旱评价的必要变量。为全面探究华中华南湿润亚热带地区ET0的时空变化规律及其主要成因,基于该地区1961~2020年246个站点的逐日气象资料和部分大气环流指数,采用Penman-Monteith法计算ET0,结合Mann-Kendall检验、Pettitt、滑动t和累积距平突变检验探究气象要素的变化规律和ET0,并利用Pearson相关分析明确ET0变化的驱动因素。结果表明:T_(mean)、T_(min)、T_(max)呈上升趋势(0.028、0.029、0.019℃/a),n、us、RH_(mean)波动下降(-0.018 h/a、-0.005 m/(s·a)、-0.052%/a),突变点依次是1996、1997、1996、1980、1988、1981、1988和2002年。ET0整体呈下降趋势,倾向率为-0.45 mm/a,夏季ET0极显著减少会导致年ET0下降,年、季尺度下ET0的空间分布较复杂。ET0与NAHAI、NANRP、APVA、NAPVA、PPVI、AEPVI和AO、AAO、NAO、EM、TSN、SOI的相关系数分别为-0.86~0.85、-0.07~0.09。ET0的下降趋势在时空上均有体现,与气象要素的变化密切相关,且太平洋区极涡强度指数PPVI是影响ET0变化的最相关因素,结论对该地区制定科学的灌溉制度具有重要意义。

关键词：参考作物腾发量突变检验时空变化气象要素大气环流指数

The Effect of Glycation of CD59 on Complement-Mediated Cytolysis

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Cellular & Molecular Immunology 2005年第4期2卷 313-317页

作者： Ying cheng Meihua Gao Department of Immunology Medical College of Qingdao University Qingdao Shandong China

Vascular proliferation is one of the major causes for morbidity and mortality in diabetes. However, the cellular and molecular mechanisms that link hyperglycemia to this complication remain unclear. In present study, we demonstrated by site-directed mutagenesis that mutated CD59 was more susceptible to glycation-inactivation for hyperglycemia. Mutated and wild-type CD59s were stably expressed in Chinese hamster ovary cells using the pALTER-max mammalian expression vector. Western blot, FACS and immunological fluorescence were conducted to confirm that CD59s were tethered to the plasma membrane. Compared to wild-type CD59, human CD59 mutants led to a significant increase in dye release assay. These results indicate that there may be some mutations of CD59 in diabetes population and the mutated CD59, which is more likely to be of glycation than the wild-type, may help to explain the distinct propensity of diabetes subjects to develop vascular proliferation complications.

关键词： CD59 site-directed mutagenesis eukaryotic expression vector

On Fixed-Parameter Solvability of the Minimax Path Location Problem

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Communications on Applied Mathematics and Computation 2023年第4期5卷 1644-1654页

作者： Hao Lin cheng He School of Science Henan University of TechnologyZhengzhou450001HenanChina

The minimax path location problem is to find a path P in a graph G such that the maximum distance d_(G)(v,P)from every vertex v∈V(G)to the path P is *** is a well-known NP-hard problem in network *** paper studies the fixed-parameter solvability,that is,for a given graph G and an integer k,to decide whether there exists a path P in G such that max v∈V(G)d_(G)(v,P)≤*** the answer is affirmative,then graph G is called *** show that this decision problem is NP-complete even for k=*** the other hand,we characterize the family of 1-path-eccentric graphs,including the traceable,interval,split,permutation graphs and ***,some polynomially solvable special graphs are discussed.

关键词： Discrete location Path location Fixed-parameter solvability Graph characterization Polynomial-time algorithm