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Journal of Meteorological Research 2023年第6期37卷 790-801页

作者： Mengxi JIN Ziyuan ZHAO Renguang WU peijun zhu School of Earth Sciences Zhejiang UniversityHangzhou310058China

The passage of tropical cyclones induces ocean surface cooling through vertical mixing,upwelling,and surface heat *** dependence of tropical cyclone-induced ocean surface cooling on the intensity and translation speed of tropical cyclones has been documented in previous *** present study investigates the latitudinal and seasonal variations in tropical cyclone-induced ocean surface cooling in the tropical western North Pacific based on data for the 2001–2020 *** analysis focuses on the open ocean(0°–25°N,130°E–180°)to reduce the interference of coastal topography so that the obtained results better represent the influences of the intensity and translation speed of tropical *** analysis confirms the dependence on the intensity and translation speed of tropical cyclone-induced *** new findings are as ***,the time to reach the maximum cooling increases with the magnitude of the maximum ***,the magnitude of ocean surface cooling increases with latitude in the tropical region for tropical cyclones with different intensities and translation ***,the ocean surface cooling is larger in summer and autumn than in spring for tropical cyclones with different intensities and translation ***,the dependence of ocean surface cooling on the translation speed is more obvious at higher latitudes in the tropics and less apparent in *** new findings add to the existing knowledge of the impacts of tropical cyclone intensity and translation speed on ocean surface cooling.

关键词： tropical cyclones ocean surface cooling intensity and translation speed latitudinal dependence seasonal variation

Climatological distribution and diurnal variation of mesoscale convective systems over China and its vicinity during summer

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Chinese Science Bulletin 2008年第10期53卷 1574-1586页

作者： ZHENG YongGuang CHEN Jiong zhu peijun National Meteorological Center Beijing 100081 China Department of Earth Sciences College of Science Zhejiang University Hangzhou 310027 China

The climatological distribution of mesoscale convective systems (MCSs) over China and its vicinity during summer is statistically analyzed, based on the 10-year (1996―2006, 2004 excluded) June-August infrared TBB (Temperature of black body) dataset. Comparing the results obtained in this paper with the distribution of thunderstorms from surface meteorological stations over China and the distribution of lightning from low-orbit satellites over China and its vicinity in the previous studies, we find that the statistic characteristics of TBB less than -52℃ can better represent the spatiotemporal distribution of MCSs over China and its vicinity during *** spreading pattern of the MCSs over this region shows three transmeridional bands of active MCSs, with obvious fluctuation of active MCSs in the band near 30°N. It can be explained by the atmospheric circulation that the three bands of active MCSs are associated with each other by the summer monsoon over East Asia. We focus on the diurnal variations of MCSs over different underlying surfaces, and the result shows that there are two types of MCSs over China and its vicinity during summer. One type of MCSs has only one active period all day long (single-peak MCSs), and the other has multiple active periods (multi-peak MCSs). Single-peak MCSs occur more often over plateaus or mountains, and multi-peak MCSs are more common over plains or basins. Depending on lifetimes and active periods, single-peak MCSs can be classified as Tibetan Plateau MCSs, general mountain MCSs, Ryukyu MCSs, and so on. The diurnal variation of multi-peak MCSs is very similar to that of MCCs (mesoscale convective complexes), and it reveals that multi-peak MCSs has longer life cycle and larger horizontal scale, becomes weaker after sunset, and develops again after midnight. Tibetan Plateau MCSs and general mountain MCSs both usually develop in the afternoon, but Tibetan Plateau MCSs have longer life cycle and more active MαCSs. Ryukyu MCSs gener

关键词：中尺度对流系统 IR TBB 白天活动规律气候分布

Surface Rainfall and Cloud Budgets Associated with Mei-yu Torrential Rainfall over Eastern China during June 2011

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Advances in Atmospheric Sciences 2014年第6期31卷 1435-1444页

作者： ZHAI Guoqing LI Xiaofan zhu peijun SHEN Hangfeng ZHANG Yuanzhi Department of Earth Sciences Zhejiang University Hangzhou Weather Bureau Aviation Agency Meteorological Observatory of Zhejiang

Surface rainfall and cloud budgets associated with three heavy rainfall events that occurred over eastern China during the mei-yu season in June 2011 were analyzed using 2D cumulus ensemble model simulation *** domain mean rainfall showed three peaks in response to three prescribed ascending motion maxima,primarily through the mean moisture convergence during the torrential rainfall *** ascending motion throughout the troposphere produced strong convective rainfall during the first （9 June） and third （17-18 June） rainfall events,whereas strong prescribed ascending motion in the mid and upper troposphere and weak subsidence near the surface generated equally important stratiform and convective rainfall during the second rainfall event （14 June）.The analysis of surface rainfall budgets reveals that convective rainfall was associated with atmospheric drying during the first event and moisture convergence during the third *** stratiform and convective rainfall responded primarily to moisture convergence during the second *** analysis of grid data shows that the first and third mean rainfall maxima had smaller horizontal scales of the precipitation system than the second.

关键词： rainfall cloud budget moisture convergence atmospheric drying convective rainfall stratiform rainfall

Mesoscale Modeling Study of Severe Convection over Complex Terrain

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Advances in Atmospheric Sciences 2016年第11期33卷 1259-1270页

作者： Ying ZHANG Zhiyong MENG peijun zhu Tao SU Guoqing ZHAI Department of Atmospheric Sciences School of Earth SciencesZhejiang University Department of Atmospheric and Oceanic Sciences School of PhysicsPeking University

Short squall lines that occurred over Lishui, southwestern Zhejiang Province, China, on 5 July 2012, were investigated using the WRF model based on 1°× 1° gridded NCEP Final Operational Global Analysis data. The results from the numerical simulations were particularly satisfactory in the simulated radar echo, which realistically reproduced the generation and development of the convective cells during the period of severe convection. The initiation of this severe convective case was mainly associated with the uplift effect of mesoscale mountains, topographic convergence, sufficient water vapor, and enhanced low-level southeasterly wind from the East China Sea. An obvious wind velocity gradient occurred between the Donggong Mountains and the southeast coastline, which easily enabled wind convergence on the windward slope of the Donggong Mountains; both strong mid–low-level southwesterly wind and low-level southeasterly wind enhanced vertical shear over the mountains to form instability; and a vertical coupling relation between the divergence on the upper-left side of the Donggong Mountains and the convergence on the lower-left side caused the convection to develop rapidly. The convergence centers of surface streams occurred over the mountain terrain and updrafts easily broke through the lifting condensation level（LCL） because of the strong wind convergence and topographic lift, which led to water vapor condensation above the LCL and the generation of the initial convective cloud. The centers of surface convergence continually created new convective cells that moved with the southwest wind and combined along the Donggong Mountains, eventually forming a short squall line that caused severe convective weather.

关键词： convective convection divergence mesoscale mountains instability southwestern terrain moved uplift

Factors contributing to the oxygen concentration over the Qinghai-Tibetan Plateau and its contribution rate calculation

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Science China Earth Sciences 2024年第2期67卷 497-509页

作者： peijun SHI Ying ZHANG Yanqiang CHEN Wenquan zhu Xiaokang HU Heyi YANG Lu JIANG Yonggui MA Haiping TANG State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing100875China Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing100875China The Institute for Disaster Management and Reconstruction Sichuan UniversityChengdu610065China Academy of Plateau Science and Sustainability People’s Government of Qinghai Province&Beijing Normal UniversityXining810016China

A decline in atmospheric oxygen concentration is projected in the 21st century given the background of global *** Qinghai-Tibetan Plateau is located at a high altitude,and thus,it faces a hypoxia challenge;however,knowledge of the factors contributing to its atmospheric oxygen concentration is still ***,we conducted joint observations of ecosystem oxygen production and carbon sinks and near-surface atmospheric oxygen concentrations on the Qinghai-Tibetan Plateau and meteorological elements at Beijing Fangshan *** seasonal differences and statistical methods,we calculated the relative contribution rates of vegetation to changes in atmospheric oxygen *** results indicate that solar radiation,atmospheric humidity,and ecosystem oxygen consumption and production have a significant impact on the atmospheric oxygen concentration,and the impact shows temporal and spatial *** significantly impacts the oxygen concentration,with a contribution rate of 16.7%–24.5%,which is underestimated in existing *** findings provide important insights into the factors that influence atmospheric oxygen concentration and highlight the contribution of *** better understand the oxygen dynamics of the Qinghai-Tibetan Plateau,we recommend further field observations of soil respiration and vegetation photosynthesis to clarify the contributions of carbon storage,carbon sinks and other factors to the near-surface atmospheric oxygen concentration.

关键词： Qinghai-Tibetan Plateau Oxygen concentration Relative contribution rate Air temperature Vegetation

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沥青路表纹理特性与抗滑性能相关关系研究

交通工程 2024年第2期24卷 62-67页

作者：黄洁玲汪嘉淇吴泽宇徐誉扬朱培军黄海南福建农林大学交通与土木工程学院福州350100

为研究沥青路面宏、微观纹理特性与抗滑性能的相关关系,选择营运中的沥青道路作为研究对象,采用激光纹理扫描小车进行沥青路面宏、微观纹理的像素值测定,使用Matlab软件重构了沥青路面的三维数据模型.同时,利用摆式摩擦测定仪测量沥青... 详细信息

为研究沥青路面宏、微观纹理特性与抗滑性能的相关关系,选择营运中的沥青道路作为研究对象,采用激光纹理扫描小车进行沥青路面宏、微观纹理的像素值测定,使用Matlab软件重构了沥青路面的三维数据模型.同时,利用摆式摩擦测定仪测量沥青路面摆值.最后,计算沥青混凝土路面纹理构造参数并分析沥青路面构造参数和路面抗滑性能指标间的相关性.研究表明:相对于路面轮廓无规则方向,路面轮廓竖直方向的评价指标与抗滑指标的相关性更强;纹理指标中,平均断面深度MPD与路面轮廓算术平均偏差Ra与路面抗滑性能具有较好的正相关关系,其中路面轮廓算术平均偏差Ra与摆值的相关性大于平均断面深度MPD与摆值的相关性.

关键词：沥青路面路表纹理特性抗滑性能激光纹理扫描法摆值

准直器角度对局部中晚期中上段食管鳞状细胞癌患者动态容积调强放射治疗计划剂量的影响

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医疗装备 2024年第9期37卷 31-34,38页

作者：金子川陈长建郗会珍葛双朱培军马俊丽魏敏潍坊医学院山东潍坊261000 济宁医学院附属医院山东济宁272000

目的探讨不同准直器角度对局部中晚期中上段食管鳞状细胞癌患者行动态容积调强放射治疗(VMAT)时剂量的影响,为放射治疗计划的设计提供参考。方法选取2020年1月至2021年8月于医院行VMAT的18例局部中晚期中上段食管鳞状细胞癌患者,在其他... 详细信息

目的探讨不同准直器角度对局部中晚期中上段食管鳞状细胞癌患者行动态容积调强放射治疗(VMAT)时剂量的影响,为放射治疗计划的设计提供参考。方法选取2020年1月至2021年8月于医院行VMAT的18例局部中晚期中上段食管鳞状细胞癌患者,在其他治疗参数不变的情况下,设置准直器角度为0°、5°、10°、15°、20°、25°、30°、35°、40°、45°、50°,设计11个计划。以准直器角度0°为参考,比较各计划的计划靶区(planning target volum,PTV)评价指标[D_(98)、D_(2)、D_(mean)、均匀性指数(HI)、适形性指数(CI)及机器跳数(monitor unit,MU)]和危及器官评价指标[双肺V_(5)、V_(15)、V_(20),心脏V_(30)、V_(40),脊髓D_(max)和脊髓规划风险量(PRV)(脊髓外扩0.40 cm得到)D_(max)]。结果准直器角度为15°时,靶区的HI、CI均最接近1,表明此时靶区的均匀性和适形性最佳。准直器角度为20°时,靶区的HI相比0°时变化明显(t=2.406,P<0.05),双肺的V_(5)、V_(15)相比0°时变化明显(t=2.959、3.003,P<0.05)。准直器角度为45°时,MU相比0°时明显增大(t=-3.444,P<0.05)。结论局部中晚期中上段食管鳞状细胞癌患者行VMAT时,15°为相对合适的准直器角度,可在保证靶区剂量分布的同时更好地保护危及器官,提高治疗效率。

关键词：准直器食管癌容积旋转调强放射治疗剂量

维普期刊数据库博看期刊

Distribution and Diurnal Variation of Warm-Season Short-Duration Heavy Rainfall in Relation to the MCSs in China

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Acta meteorologica Sinica 2013年第6期27卷 868-888页

作者：陈炯郑永光张小玲朱佩军 National Meteorological Center China Meteorological Administration Zhejiang University

Short-duration heavy rainfall（SDHR） is a type of severe convective weather that often leads to substantial losses of property and life. We derive the spatiotemporal distribution and diurnal variation of SDHR over China during the warm season（April–September） from quality-controlled hourly raingauge data taken at 876 stations for 19 yr（1991–2009）, in comparison with the diurnal features of the mesoscale convective systems（MCSs） derived from satellite data. The results are as follows. 1） Spatial distributions of the frequency of SDHR events with hourly rainfall greater than 10–40 mm are very similar to the distribution of heavy rainfall（daily rainfall 50 mm） over China's Mainland. 2） SDHR occurs most frequently in South China such as southern Yunnan, Guizhou, and Jiangxi provinces, the Sichuan basin, and the lower reaches of the Yangtze River, among others. Some SDHR events with hourly rainfall 50 mm also occur in northern China, e.g., the western Xinjiang and central-eastern Inner Mongolia. The heaviest hourly rainfall is observed over the Hainan Island with the amount reaching over 180 mm. 3） The frequency of the SDHR events is the highest in July, followed by August. Analysis of pentad variations in SDHR reveals that SDHR events are intermittent, with the fourth pentad of July the most active. The frequency of SDHR over China's Mainland increases slowly with the advent of the East Asian summer monsoon, but decreases rapidly with its withdrawal. 4） The diurnal peak of the SDHR activity occurs in the later afternoon（1600–1700 Beijing Time（BT））, and the secondary peak occurs after midnight（0100–0200 BT） and in the early morning（0700–0800 BT）; whereas the diurnal minimum occurs around late morning till noon（1000–1300 BT）. 5） The diurnal variation of SDHR exhibits generally consistent features with that of the MCSs in China, but the active periods and propagation of SDHR and MCSs difer in diferent regions. The number and duration of local maxima in the diurnal cycles of

关键词： short-duration heavy rainfall climatology spatiotemporal distributions diurnal variation propagation mesoscale convective systems(MCSs

Clinical outcomes of second-line chemotherapy in patients with advanced pancreatic adenocarcinoma:a real-world study

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Cancer Biology & Medicine 2024年第9期21卷 799-812页

作者： Yuxiao Liu Xiaofan Guo peijun Xu Yuning Song Jing Huang Xingyun Chen Wenbo zhu Jihui Hao Song Gao Department of Pancreatic Cancer Tianjin Medical University Cancer Institute&HospitalNational Clinical Research Center for CancerKey Laboratory of Cancer Prevention and TherapyTianjinTianjin's Clinical Research Center for CancerTianjin 300060China

Objective:Little progress has been made in recent years using first-line chemotherapy,including gemcitabine combined with nab-paclitaxel,FOLFIRINOX,and NALIRIFOX,for advanced pancreatic adenocarcinoma(APC).In addition,the optimal second-line chemotherapy regimen has not been *** study aimed to compare the effectiveness of different types of second-line chemotherapy for ***:Patients with APC who received first-line treatment from January 2008 to January 2021 were considered eligible for this retrospective *** primary and secondary endpoints were overall survival(OS)and progression-free survival(PFS),***:Four hundred and thirty-seven and 617 patients were treated with 5-fluorouracil-and gemcitabine-based chemotherapy as first-line treatment,*** and clinical features,except age and liver metastasis,were comparable between the two groups(P<0.05).The median OS was 8.8 and 7.8 months in patients who received a 5-fluorouracil-and gemcitabine-based combined regimen for first-line therapy,respectively(HR=1.244,95%CI=1.090–1.419;P<0.001).The median OS was 5.6 and 1.9 months in patients who received second-line chemotherapy and supportive care,respectively(HR=0.766,95%CI=0.677–0.867;P<0.001).The median PFS was not significantly differently between gemcitabine or 5-fluorouracil monotherapy and combination ***:A 5-fluorouracil-or gemcitabine-based combined regimen was shown to be as effective as a single 5-fluorouracil or gemcitabine regimen as second-line therapy for patients with APC.

关键词： Second-line chemotherapy advanced pancreatic adenocarcinoma 5-fluorouracil gemcitabine real-world study

西北太平洋热带气旋快速加强的环境场变量影响

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浙江大学学报（理学版） 2023年第2期50卷 213-224页

作者：童梦烨朱佩君浙江大学地球科学学院浙江杭州310027

利用中国气象局(CMA)整编的西北太平洋1999—2018年热带气旋最佳路径数据集和美国国家环境预报中心(NCEP)再分析资料,结合均值、标准差、极端天气阈值等方法,确定热带气旋快速加强(RI)的阈值为-29.82 hPa·(24 h)^(-1),统计发现西北太... 详细信息

利用中国气象局(CMA)整编的西北太平洋1999—2018年热带气旋最佳路径数据集和美国国家环境预报中心(NCEP)再分析资料,结合均值、标准差、极端天气阈值等方法,确定热带气旋快速加强(RI)的阈值为-29.82 hPa·(24 h)^(-1),统计发现西北太平洋地区RI主要发生在7—10月,集中在5°N~20°N、120°E~160°E洋面。通过对RI与非快速加强(non-RI)的动态合成分析,对比2类样本多个环境变量的差异,结果发现:(1)RI对环境变量的响应时间与相关系数相关,对RI响应时间越早的环境变量,与RI的相关性越大;(2)对RI影响较显著的是海表面温度、高层散度和垂直风切变,其次是中层相对湿度和低层散度,影响较弱的是低层水汽通量散度和相对涡度;(3)热带气旋初始强度影响各环境变量对RI过程发生的贡献。

关键词：热带气旋快速加强快速加强阈值环境变量