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V掺杂对CoCrFeNiV_(x)高熵合金相结构的影响

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四川师范大学学报（自然科学版） 2024年第5期47卷 656-661页

作者：王俊余韵严成龙张远春李强王江张仁辉攀枝花钢城集团有限公司四川攀枝花617000 攀枝花学院钒钛学院四川攀枝花617000 华东交通大学材料科学与工程学院江西南昌330013

采用相图计算方法(CALPHAD),应用热力学计算模型对高熵合金CoCrFeNiV_(x)(x=0.0~1.0)的相图进行模拟,并用分子动力学方法对V掺杂的高熵合金CoCrFeNiV_(0.2)的强度和温度的关系以及变形机制进行研究.结果发现,未掺V时,室温下体系有4种相... 详细信息

采用相图计算方法(CALPHAD),应用热力学计算模型对高熵合金CoCrFeNiV_(x)(x=0.0~1.0)的相图进行模拟,并用分子动力学方法对V掺杂的高熵合金CoCrFeNiV_(0.2)的强度和温度的关系以及变形机制进行研究.结果发现,未掺V时,室温下体系有4种相,分别为BCC-A2、BCC-A2#2、FCC-A1和SIGMA相,SIGMA相含量最高,随着温度升高到550 K,BCC-A2和BCC-A2#2相消失,FCC-A1成分下降,SIGMA相成分达到极大值.当V含量为0.2时,室温下体系有3种相,分别为BCC-A2、FCC-A1和BCC-A2#2相,随着温度升高到600 K,BCC-A2和BCC-A2#2相含量减少,FCC-A1相增加,同时SIGMA相出现.在600~620 K区间发生BCC-A+BCC-A2#2→SIGMA转变,并在990 K时,SIGMA相完全消失.当V含量为0.4~1.0时,600~800 K区间SIGMA相含量均高于V含量为0.2时的相图.因此,V元素的掺入有助于抑制高熵合金CoCrFeNiV_(x)脆性SIGMA相出现.此外,通过分子动力学模拟发现,高熵合金CoCrFeNiV_(0.2)的变形机制主要为晶粒旋转、晶内层错以及非晶化.

关键词：相图计算方法高熵合金 CoCrFeNiV 相图

加速康复外科在基层医院老年腹股沟疝围术期的应用

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临床研究 2024年第7期32卷 135-137页

作者：金齐敏柏涌海俞璟滢张援春张丹周明杨雅徐汇区大华医院普外科上海200231 上海长征医院心理医学科上海200003

目的探讨基层医院老年腹股沟疝患者围术期快速康复的应用价值,为建立基层医院老年腹股沟疝围术期快速康复路径提供依据。方法选取2022年6月至2022年12月徐汇区大华医院普外科120例老年腹股沟疝手术患者,随机分为观察组60例,对照组60例... 详细信息

目的探讨基层医院老年腹股沟疝患者围术期快速康复的应用价值,为建立基层医院老年腹股沟疝围术期快速康复路径提供依据。方法选取2022年6月至2022年12月徐汇区大华医院普外科120例老年腹股沟疝手术患者,随机分为观察组60例,对照组60例。对照组采用一般管理模式,观察组采用快速康复理念管理,对比两组患者术后疼痛情况、术后恢复情况、满意度及并发症发生率。结果两组术后6 h疼痛评分比较差异无统计学意义(P>0.05),观察组术后1 d、术后3 d疼痛评分均低于对照组,差异有统计学意义(P<0.05);观察组首次排气、排便时间、住院天数短于对照组,观察组患者满意度高于对照组,并发症发生率低于对照组,差异均有统计学意义(P<0.05)。结论在老年腹股疝围术期使用加速康复理念,可以减轻疼痛,促进胃肠功能尽早恢复,减少住院天数,降低并发症,值得基层医院应用。

关键词：快速康复基层医院老年腹股沟疝手术

The comparison of statistical features and synoptic circulations between the eastward-propagating and quasi-stationary MCSs during the warm season around the second-step terrain along the middle reaches of the Yangtze River

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Science China Earth Sciences 2020年第8期63卷 1209-1222页

作者： Ruyi YANG yuanchun zhang Jianhua SUN Jun LI Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China University of the Chinese Academy of Sciences Beijing 100049China 31010 PLA Troops Beijing 100081China

Mesoscale convective systems(MCSs) around the second-step terrain(106°–113°E, 28°–35°N), along the middle reaches of the Yangtze River, were detected, tracked and classified using a black body temperature(TBB) dataset during May to August 2000–2016(except 2005). The MCSs were divided into eastward-propagating(EP) and quasi-stationary(QS) types, to compare their spatial and temporal distributions and convective intensities, and to identify the favorable synoptic conditions for the formation and evolution of EP MCSs. The results showed that both MCS types occurred most often in July. The EP MCSs were mainly initiated over the eastern regions of the study area, while the QS type mainly originated in the western regions of the study area. Both MCS types mainly formed in the afternoon, but a second peak occurred in the early morning for QS MCSs. The EP MCSs had a larger cloud area at their mature stage and a lower cloud brightness temperature, indicating more intense convection. Additionally, the longer lifetime and further eastward propagation of the EP MCSs meant that they had a great influence on the precipitation over the middle and lower reaches of the Yangtze River. Synoptic circulation analysis demonstrated that the combination of the mid-level low trough east of the Tibetan Plateau(TP), and the western pacific subtropical high(WPSH), favored the formation and eastward propagation of EP MCSs. The positive vertical relative vorticity and stronger vertical wind shear provided dynamic conditions favorable for convective organization and development. Furthermore, a stronger low level jet imported warm and moist air to the eastern edge of, and the regions east of, the second-step terrain. The substantial convergence of water vapor promoted the development and long-lived maintenance of the EP MCSs.

关键词： Second-step terrain Middle reaches of the Yangtze River Mesoscale convection systems.Spatial and temporal distribution Synoptic circulation

Impacts of Diurnal Variation of Mountain-plain Solenoid Circulations on Precipitation and Vortices East of the Tibetan Plateau during the Mei-yu Season

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Advances in Atmospheric Sciences 2014年第1期31卷 139-153页

作者： zhang yuanchun SUN Jianhua FU Shenming Institute of Atmospheric Physics Chinese Academy of Sciences Graduate University of the Chinese Academy of Sciences State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences

Diurnal variations of two mountain-plain solenoid （MPS） circulations associated with ＂first-step＂ terrain [Tibetan Plateau （TP）] and ＂second-step＂ terrain （high mountains between the TP and ＂east plains＂） in China and their influence on the south west vortex （SWV） and the mei-yu front vortex （MYFV） were investigated via a semi-idealized mesoscale numerical model [Weather Research and Forecasting （WRF）] simulation integrated with ten-day average fields （mei-yu period of 1-10 July 2007）. The simulations successfully reproduced two MPS circulations related to first and second-step terrain, diurnal vari- ations from the eastern edge of the TP to the Yangtze River-Huaihe River valleys （YHRV）, and two precipitation maximum centers related to the SWV, MYFV. Analyses of the averaged final seven-day simulation showed the different diurnal peaks of precipitation at different regions： from the aftemoon to early evening at the eastern edge of the TP; in the early evening to the next early morning in the Sichuan Basin （SCB）; and in the late evening to the next early morning over the mei-yu front （MYF）. Analyses of individual two-day cases confirmed that the upward branches of the nightlime MPS circulations enhanced the precipitation over the SWV and the MYFV and revealed that the eastward extension of the SWV and its con vection were conducive to triggering the MYFVs. The eastward propagation of a rainfall streak from the eastern edge of the TP to the eastern coastal region was primarily due to a series of convective activities of several systems from west to east, including the MPS between the TP and SCB, the SWV, the MPS between second-step terrain and tile east plains, and the MYFV.

关键词： mountain-plain solenoid (MPS) diurnal variation mei-yu front

Main Energy Paths and Energy Cascade Processes of the Two Types of Persistent Heavy Rainfall Events over the Yangtze River–Huaihe River Basin

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Advances in Atmospheric Sciences 2017年第2期34卷 129-143页

作者： yuanchun zhang Jianhua SUN Shenming FU Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China 1nternational Center for Climate and Environment Sciences Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

Two types of persistent heavy rainfall events （PHREs） over the Yangtze River-Huaihe River Basin were determined in a recent statistical study： type A, whose precipitation is mainly located to the south of the Yangtze River; and type B, whose precipitation is mainly located to the north of the river. The present study investigated these two PHRE types using a newly derived set of energy equations to show the scale interaction and main energy paths contributing to the persistence of the precipitation. The main results were as follows. The available potential energy （APE） and kinetic energy （KE） associated with both PHRE types generally increased upward in the troposphere, with the energy of the type-A PHREs stronger than that of the type-B PHREs （except for in the middle troposphere）. There were two main common and universal energy paths of the two PHRE types：（1） the baroclinic energy conversion from APE to KE was the dominant energy source for the evolution of large-scale background circulations; and （2） the downscaled energy cascade processes of KE and APE were vital for sustaining the eddy flow, which directly caused the PHREs. The significant differences between the two PHRE types mainly appeared in the lower troposphere, where the baroclinic energy conversion associated with the eddy flow in type-A PHREs was from KE to APE, which reduced the intensity of the precipitation-related eddy flow; whereas, the conversion in type-B PHREs was from APE to KE, which enhanced the eddy flow.

关键词： persistent heavy rainfall event energy cascade process large-scale background circulation precipitation-related eddy flow

Typical Circulation Patterns and Associated Mechanisms for Persistent Heavy Rainfall Events over Yangtze–Huaihe River Valley during 1981–2020

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Advances in Atmospheric Sciences 2021年第12期38卷 2167-2182页

作者： Huijie WANG Jianhua SUN Shenming FU yuanchun zhang Key Laboratory of Cloud-Precipitation Physics and Severe Storms(LACS) Institute of Atmospheric PhysicsChinese Academy of ScienceBeijing 100029China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China University of Chinese Academy of Sciences Beijing 100029China International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Persistent heavy rainfall events(PHREs)over the Yangtze–Huaihe River Valley(YHRV)during 1981–2020 are classified into three types(type-A,type-B and type-C)according to pattern *** characteristics of the synoptic systems for the PHREs and their possible development mechanisms are *** anomalous cyclonic disturbance over the southern part of the YHRV during type-A events is primarily maintained and intensified by the propagation of Rossby wave energy originating from the northeast Atlantic in the mid–upper troposphere and the northward propagation of Rossby wave packets from the western Pacific in the mid–lower *** zonal propagation of Rossby wave packets and the northward propagation of Rossby wave packets during type-B events are more coherent than those for type-A events,which induces eastward propagation of stronger anomaly centers of geopotential height from the northeast Atlantic Ocean to the YHRV and a meridional anomaly in geopotential height over the Asian ***-C events have“two ridges and one trough”in the high latitudes of the Eurasian continent,but the anomalous intensity of the western Pacific subtropical high(WPSH)and the trough of the YHRV region are weaker than those for type-A and type-B *** composite synoptic circulation of four PHREs in 2020 is basically consistent with that of the corresponding PHRE *** location of the South Asian high(SAH)in three of the PHREs in 2020 moves eastward as in the composite of the three types,but the position of the WPSH of the four PHREs is clearly westward and *** water vapor conveyor belts and two cold air conveyor belts are tracked during the four PHREs in 2020,but the water vapor path from the western Pacific is not seen,which may be caused by the westward extension of the WPSH.

关键词： persistent heavy rainfall events Yangtze-Huaihe River Valley Rossby wave energy dispersion water vapor paths cold air paths

基于氧化应激途径探讨人参益脉方干预血管老化作用机制

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中国中医药信息杂志 2024年第7期31卷 63-68页

作者：石丹丹宁梓淇郭晓晨张瑶瑶张元春张海燕刘美霞刘剑刚中国中医科学院西苑医院北京100091 中国中医科学院研究生院北京100700

目的观察人参益脉方对ApoE^(-/-)小鼠氧化应激及血管老化的影响,探讨其干预血管老化的作用机制。方法将40只ApoE^(-/-)小鼠随机分为模型组、西药组(瑞舒伐他汀,2.6 mg/kg)及中药低、高剂量组(人参益脉方,4.29、8.58 g/kg),每组10只,另... 详细信息

目的观察人参益脉方对ApoE^(-/-)小鼠氧化应激及血管老化的影响,探讨其干预血管老化的作用机制。方法将40只ApoE^(-/-)小鼠随机分为模型组、西药组(瑞舒伐他汀,2.6 mg/kg)及中药低、高剂量组(人参益脉方,4.29、8.58 g/kg),每组10只,另取10只C57BL/6J小鼠作为正常组。采用西式饮食饲料喂养ApoE^(-/-)小鼠建立血管老化模型,同时各给药组分别予相应药物灌胃,正常组和模型组灌胃等体积纯净水,连续12周。HE染色及Masson染色观察小鼠主动脉组织形态变化,ELISA检测血清氧化型低密度脂蛋白(ox-LDL)含量,比色法测定血清活性氧(ROS)、谷胱甘肽(GSH)、谷胱甘肽还原酶(GPX)、烟酰胺腺嘌呤二核苷酸(NAD^(+))含量,Western blot检测主动脉组织沉默信息调节因子1(SIRT1)、p21、p53、NADPH氧化酶4(NOX4)蛋白表达。结果与正常组比较,模型组小鼠主动脉可见脂质沉积,内膜及中膜明显增厚,弹性纤维减少,胶原纤维增多;血清ox-LDL、ROS含量显著升高(P<0.01),GSH、GPX、NAD^(+)含量显著降低(P<0.01);主动脉组织SIRT1蛋白表达显著降低(P<0.05),p21、p53蛋白表达显著升高(P<0.01,P<0.05)。与模型组比较,各给药组主动脉内膜可见少量脂质沉积,各层膜结构较清晰,胶原纤维减少;各给药组血清ox-LDL、ROS含量显著降低(P<0.01),GSH含量显著升高(P<0.05,P<0.01),中药低剂量组NAD^(+)含量显著升高(P<0.05);中药高剂量组主动脉组织p21、NOX4蛋白表达显著升高(P<0.05,P<0.01)。与西药组比较,中药高剂量组ROS含量显著降低(P<0.01),p53蛋白表达显著降低(P<0.05)。与中药低剂量组比较,中药高剂量组p21蛋白表达显著降低(P<0.01),NOX4蛋白表达显著升高(P<0.01)。结论人参益脉方可能通过调节氧化应激水平和相关蛋白表达减轻血管内皮损伤,从而发挥改善血管老化作用。

关键词：人参益脉方血管老化 ApoE-/-小鼠氧化应激

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A Review of Research on Warm-Sector Heavy Rainfall in China

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Advances in Atmospheric Sciences 2019年第12期36卷 1299-1307页

作者： Jianhua SUN yuanchun zhang Ruixin LIU Shenming FU Fuyou TIAN Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China Beijing Municipal Weather Forecast Center Beijing 100089China National Meteorological Center China Meteorological AdministrationBeijing 100081China

Warm-sector heavy rainfall (WSHR) events in China have been investigated for many years. Studies have investigated the synoptic weather conditions during WSHR formation, the categories and general features, the triggering mechanism, and structural features of mesoscale convective systems during these rainfall events. The main results of WSHR studies in recent years are summarized in this paper. However, WSHR caused by micro- to mesoscale systems often occurs abruptly and locally, making both numerical model predictions and objective forecasts difficult. Further research is needed in three areas:(1) The mechanisms controlling WSHR events need to be understood to clarify the specific effects of various factors and indicate the influences of these factors under different synoptic background circulations. This would enable an understanding of the mechanisms of formation, maintenance, and organization of the convections in WSHR events.(2) In addition to South China, WSHR events also occur during the concentrated summer precipitation in the Yangtze River-Huaihe River Valley and North China. A high spatial and temporal resolution dataset should be used to analyze the distribution and environmental conditions, and to further compare the differences and similarities of the triggering and maintenance mechanisms of WSHR events in different regions.(3) More studies of the mechanisms are required, as well as improvements to the model initial conditions and physical processes based on multi-source observations, especially the description of the triggering process and the microphysical parameterization. This will improve the numerical prediction of WSHR events.

关键词： warm-sector heavy rainfall synoptic weather conditions triggering mechanism South China

A semi-idealized modeling study on the long-lived eastward propagating mesoscale convective system over the Tibetan Plateau

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Science China Earth Sciences 2021年第11期64卷 1996-2014页

作者： Shenming FU Zi MAI Jianhua SUN Wanli LI Qi ZHONG Jiaren SUN yuanchun zhang International Center for Climate and Environment Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Heavy Rain and Drought-Flood Disasters in Plateau and Basin Key Laboratory of Sichuan Province Chengdu 610225China National Meteorological Center of China Meteorological Administration Beijing 100081China Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China China Meteorological Administration Training Center Beijing 100081China Key Laboratory of Urban Ecological Environmental Simulation and Protection of Ministry of Environmental Protection South China Institute of Environmental Sciencesthe Ministry of Environmental Protection of ChinaGuangzhou 501530China

Based on a 16-warm-season statistical study on the mesoscale convective systems(MCSs)that were generated over the Tibetan Plateau(TP),11 long-lived eastward propagating MCSs of the same type were selected for a composite semiidealized simulation and a corresponding no-latent-heating sensitivity run by using the Weather Research and Forecasting(WRF)*** evolutionary features and associated mechanisms of this type of long-lived eastward propagating MCS were *** results are as follows:(i)This type of MCS was generated in a favorable background environment which was characterized by a notable upper-tropospheric divergence south of an upper-level jet,a strong warm advection around a middle-level shortwave trough’s central area,and an instable convective stratification below the *** of the MCS featured rapid increase of cyclonic vorticity in the middle and lower *** convergence-related vertical stretching and tilting were key factors for the cyclonic-vorticity’s production,and convection-related upward cyclonic-vorticity transport contributed to the upward extending of the MCS.(ii)During the vacating stage of the MCS,it first coupled with a quasistationary Tibetan Plateau vortex(TPV)over the TP’s eastern section,and then decoupled from the *** the former stage,the MCS contributed to maintaining ascending motions and convergence associated with the TPV,which favored its persistence;whereas,in the latter stage,decoupling weakened the TPV-associated convection *** reduced the upward transport of cyclonic vorticity notably,which,together with the negative tilting effect,finally led to the vortex’s dissipation.(iii)After vacating TP,the MCS first weakened due to the disappearance of strong direct sensible heating from the TP on its bottom,and then,under the favorable conditions associated with the shortwave trough over the eastern section of the TP,the MCS redeveloped ***-related cyclonic-vor

关键词： Tibetan Plateau Mesoscale convective system Tibetan Plateau vortex Heavy rainfall Vorticity budget Sensitivity simulation