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汉代“变事”及相关用语探赜——以出土文献为中心
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作者 李沈阳 《滨州学院学报》 2024年第3期83-89,I0002,共8页
变事是汉代传世与出土文献中的习用语,指非常之事或变事书——章奏文书的一种。围绕变事,文献中的相关用语所指各有差异:言变事指报告非常之事,言变事者和言变事书分别指报告非常之事的人和章奏文书;上变事指上报非常之事给皇帝,其比上... 变事是汉代传世与出土文献中的习用语,指非常之事或变事书——章奏文书的一种。围绕变事,文献中的相关用语所指各有差异:言变事指报告非常之事,言变事者和言变事书分别指报告非常之事的人和章奏文书;上变事指上报非常之事给皇帝,其比上言变事更为常见,是变事和言变事进入上报程序的体现,并衍生出系列规定,即上变事制度。从法制史视角看,出土文献比传世文献展现更多汉代上变事制度的形成轨迹和例证,提供了汉代诏书转化为律令的直接证据,透露出汉代律令“因事立法”的特点,也有助于了解散佚的《变事令》。 展开更多
关键词 汉代 变事 章奏文书 出土文献 法制史
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新出尚德街東漢簡牘所見“上言變事”制度
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作者 吴方基 《简帛研究》 2019年第1期298-311,共14页
新出長沙尚德街東漢簡牘記載部分失傳的東漢靈帝時期關於"上言變事"之成文法,據此可再考察漢代"上言變事"制度。從運行機制視角分析,漢代"上言變事"主體分三類:普通民衆、官吏與匿名上書;"變事書&qu... 新出長沙尚德街東漢簡牘記載部分失傳的東漢靈帝時期關於"上言變事"之成文法,據此可再考察漢代"上言變事"制度。從運行機制視角分析,漢代"上言變事"主體分三類:普通民衆、官吏與匿名上書;"變事書"製作方式有"自書"和地方官吏代爲製作;"變事書"以三種方式上報:自詣公車司馬門、地方官吏傳遞、匿名上報等;上報中,法律規定盗取、留難、拆封變事書者處以極刑;所上"變事書"交付公車令,由公車令審核後上呈皇帝;皇帝對其處理方式有:同大臣商量裁决和直接下達主管官吏審查。從法律層面看,"變事"實指上報運作之"變事書",其性質是:一,從皇帝的角度看,它體現最高權力對國家、社會毛細滲透及其把控。二,從吏民的角度看,它被視爲一種吏民直接與皇帝溝通的途徑;三,從治理的角度看,它是爲吏民相互監督的直接方式。 展开更多
关键词 尚德街東漢簡牘 “上言變”制度 運行機制
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从新桂系与中共的合作与冲突看皖南事变的发生 被引量:5
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作者 黄昊 《史学集刊》 CSSCI 北大核心 2014年第1期113-120,共8页
皖南事变的最终发生,实际上是新桂系、中共、三战区三方博弈的结果。新桂系安徽省府与中共的关系从抗战初期的密切合作,逐步发展到皖南事变前夕的势若水火,在很大程度上左右了皖南新四军对北移路线的选择,最终导致了皖南事变的发生。
关键词 新桂系 中国共产党 皖南 安徽
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从《原道》到《论变盐法事宜状》——试析韩愈“四民并重、各得其所”的社会经济思想
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作者 李菁 李芊 《周口师范学院学报》 CAS 2006年第6期9-12,共4页
文章从韩愈《原道》一文中设计的儒家理想社会模式及其君臣民相生养观、四民并重尽职守分观出发,对其《送许郢州序》、《论变盐法事宜状》等文章中所体现的经济思想进行了重新审视,主要分析其中所见之韩愈对农、商问题的看法和态度。从... 文章从韩愈《原道》一文中设计的儒家理想社会模式及其君臣民相生养观、四民并重尽职守分观出发,对其《送许郢州序》、《论变盐法事宜状》等文章中所体现的经济思想进行了重新审视,主要分析其中所见之韩愈对农、商问题的看法和态度。从中可以看到韩愈一以贯之的社会经济思想,即四民并重、各得其所,各致其能。 展开更多
关键词 《原道》 《论盐法宜状》 四民并重 各得其所
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任期制视野下领导干部防避决策“好事变坏事”的现实考量
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作者 罗心欲 杨小松 《领导科学》 北大核心 2021年第5期22-25,共4页
任期制下领导干部决策“好事变坏事”是一种决策异化问题,主要呈现为“好心办坏事”“好头变烂尾”“一时好过时差”“好事似是而非”等样态,根源在于个人决策动机不纯、个人决策力缺失、决策自带不确定性、决策环境和条件限制等。防避... 任期制下领导干部决策“好事变坏事”是一种决策异化问题,主要呈现为“好心办坏事”“好头变烂尾”“一时好过时差”“好事似是而非”等样态,根源在于个人决策动机不纯、个人决策力缺失、决策自带不确定性、决策环境和条件限制等。防避决策“好事变坏事”,领导干部应树立正确政绩观,找准决策站位;活用矛盾分析法,彰显决策立意;下好应变先手棋,增强决策定力;提升系统竞争力,保证决策质量。 展开更多
关键词 任期制 领导干部 决策 “好
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浅谈我院开设医事法专业的必要性和可行性 被引量:4
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作者 张传友 《青海医学院学报》 CAS 2002年第1期54-54,62,共2页
关键词 开设 必要性 可行性 青海医学院 高校
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才全而德不形——读《庄》漫笔之十
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作者 王锺陵 《苏州科技学院学报(社会科学版)》 1999年第2期37-44,共8页
庄子是先秦时代对个体命运感作出最为突出阐述的哲人。在传统的天命观的笼罩下,命运感的抬头所反映的乃是社会化进程的扩大中个人意识的生成与孽育。庄子认为,既然死生存亡、穷达毁誉、饥渴寒暑这一类事情的产生,不是个人的智慧所能预料... 庄子是先秦时代对个体命运感作出最为突出阐述的哲人。在传统的天命观的笼罩下,命运感的抬头所反映的乃是社会化进程的扩大中个人意识的生成与孽育。庄子认为,既然死生存亡、穷达毁誉、饥渴寒暑这一类事情的产生,不是个人的智慧所能预料,那末就不要让这一类充满差异性的事情扰乱了自己对于事物通同性、亦即统一性的认识。只要对于事物统一性的认识不被扰乱,那末生命展开过程的种种得失就不会进入自己的心灵。庄子所提倡的人格是“才全而德不形”。所谓“才全”即知之全也,所谓知之全,即是所知为其大者,为其整体者也,是一种带有总体性的认识。如何对待命运,亦即是如何对待人生,这对于个体的人来说,不仅是一种总体性的认识,而且还是一种总体性的生活态度。所谓“德不形”,是说德浑化于无形。因为在东方专制社会的环境中,特别是作为弱者,才或德的外露是一件危险的事,才与德之浑化于无形这一观点的提出,表明《德充符》篇比之《养生主》与《人间世》,在对东方国家个体存在论的阐述上,又有了新的推进。 展开更多
关键词 命之行 成和之修 内保之而外不荡
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论吴歌《六变》的“因事制哥”
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作者 孙尚勇 《文学遗产》 CSSCI 北大核心 2006年第5期29-35,共7页
研究《六变》最为关键的是如何理解《宋书·乐志一》“《六变》诸曲,皆因事制哥”的记载。通过解读相关史料,进而指出,“因事制哥”是以其他故事为基本的表现内容,依托现有的特定乐曲来编创歌辞,并对乐曲的和送声略加改变,进而付诸... 研究《六变》最为关键的是如何理解《宋书·乐志一》“《六变》诸曲,皆因事制哥”的记载。通过解读相关史料,进而指出,“因事制哥”是以其他故事为基本的表现内容,依托现有的特定乐曲来编创歌辞,并对乐曲的和送声略加改变,进而付诸表演。 展开更多
关键词 吴歌《六 制哥
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Modern treatment of gastric gastrointestinal stromal tumors 被引量:17
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作者 Kevin K Roggin Mitchell C Posner 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第46期6720-6728,共9页
Gastrointestinal stromal tumors (GIST) are rare mesenchymal smooth muscle sarcomas that can arise anywhere within the gastrointestinal tract. Sporadic mutations within the tyrosine kinase receptors of the interstitial... Gastrointestinal stromal tumors (GIST) are rare mesenchymal smooth muscle sarcomas that can arise anywhere within the gastrointestinal tract. Sporadic mutations within the tyrosine kinase receptors of the interstitial cells of Cajal have been identified as the key molecular step in GIST carcinogenesis. Although many patients are asymptomatic, the most common associated symptoms include: abdominal pain, dyspepsia, gastric outlet obstruction, and anorexia. Rarely, GIST can perforate causing life-threatening hemoperitoneum. Most are ultimately diagnosed on cross-sectional imaging studies (i.e., computed tomography and/or magnetic resonance imaging in combination with upper endoscopy. Endoscopic ultrasonographic localization of these tumors within the smooth muscle layer and acquisition of neoplastic spindle cells harboring mutations in the c-KIT gene is pathognomonic. Curative treatment requires a complete gross resection of the tumor. Both open and minimally invasive operations have been shown to reduce recurrence rates and improve long-term survival. While there is considerable debate over whether GIST can be benign neoplasms, we believe that all GIST have malignant potential, but vary in their propensity to recur after resection and metastasize to distant organ sites. Prognostic factors include location, size (i.e., > 5 cm), grade (> 5-10 mitoses per 50 high power fields and specific mutational events that are still being defined. Adjuvant therapy with tyrosine kinase inhibitors, such as imatinib mesylate, has been shown to reduce the risk of recurrence after one year of therapy. Treatment of locally-advanced or borderline resectable gastric GIST with neoadjuvant imatinib has been shown to induce regression in a minority of patients and stabilization in the majority of cases. This treatment strategy potentially reduces the need for more extensive surgical resections and increases the number of patients eligible for curative therapy. The modern surgical treatment of gastric GIST combines the novel use of targeted therapy and aggressive minimally invasive surgical procedures to provide effective treatment for this lethal, but rare gastrointestinal malignancy. 展开更多
关键词 Gastrointestinal stromal tumors Laparoscopic resections of gastrointestinal stromal tumors Imatinib mesylate Gastrectomy
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Conformal Invariance and Noether Symmetry, Lie Symmetry of Birkhoffian Systems in Event Space 被引量:4
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作者 张毅 《Communications in Theoretical Physics》 SCIE CAS CSCD 2010年第1期166-170,共5页
This paper focuses on studying a conformal invariance and a Noether symmetry, a Lie symmetry for a Birkhoffian system in event space. The definitions of the conformal invariance of the system are given. By investigati... This paper focuses on studying a conformal invariance and a Noether symmetry, a Lie symmetry for a Birkhoffian system in event space. The definitions of the conformal invariance of the system are given. By investigation on the relations between the conformal invariance and the Noether symmetry, the conformal invariance and the Lie symmetry, the expressions of conformal factors of the system under these circumstances are obtained. The Noether conserved quantities and the Hojman conserved quantities directly derived from the conformal invariance are given. Two examples are given to illustrate the application of the results. 展开更多
关键词 Birkhoffian system event space conformal invariance Noether symmetry Lie symmetry
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Potential control of climatic changes on flood events in the Yangtze Delta during1100-2002 被引量:5
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作者 JIANGTong ZHANGQiang YvesGUERNOND 《Journal of Geographical Sciences》 SCIE CSCD 2004年第1期70-80,共11页
Wide collection on the historic records of the climatic changes and flood events is performed in the Yangtze Delta. Man-Kendall (MK) method is applied to explore the changing trends of the time series of the flood dis... Wide collection on the historic records of the climatic changes and flood events is performed in the Yangtze Delta. Man-Kendall (MK) method is applied to explore the changing trends of the time series of the flood discharge and the maximum high summer temperature. The research results indicate that the flood magnitudes increased during the transition from the medieval warm interval into the early Little Ice Age. Fluctuating climate changes of the Little Ice Age characterized by arid climate events followed by the humid and cold climate conditions give rise to the frequent flood hazards. Low-lying terrain made the study region prone to the flood hazards, storm tide and typhoon. MK analysis reveals that the jumping point of the time series of the flood discharge changes occurred in the mid-1960s, that of the maximum summer temperature changes in the mid-1990s, and the exact jump point in 1993. The flood discharge changes are on negative trend before the 1990s, they are on positive tendency after the 1990s; the maximum high summer temperature changes are on negative trend before the 1990s and on positive tendency after the 1990s. These results indicate that the trend of flood discharge matches that of the maximum high summer temperature in the Yangtze Delta. The occurrence probability of the maximum high summer temperature will be increasing under the climatic warming scenario and which will in turn increase the occurrence probability of the flood events. More active solar action epochs and the higher sea surface temperature index (SST index) of the south Pacific Ocean area lying between 4 o N-4 o S and 150 o W-90 o W correspond to increased annual precipitation, flood discharge and occurrence frequency of floods in the Yangtze Delta. This is partly because the intensified solar activities and the higher SST index give rise to accelerated hydrological circulation from ocean surface to the continent, resulting in increased precipitation on the continent. 展开更多
关键词 Yangtze Delta historical and instrumental climate changes Mann-Kendall method climate control on flood events
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Construction of crash prediction model of freeway basic segment based on interactive influence of explanatory variables
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作者 王晓飞 李新伟 +2 位作者 符锌砂 赵立萱 刘小峰 《Journal of Southeast University(English Edition)》 EI CAS 2015年第2期276-281,共6页
In order to improve the prediction precision of the safety performance function (SPF) of freeway basic segments, design and crash data of 640 segments are collected from different institutions. Three negative binomi... In order to improve the prediction precision of the safety performance function (SPF) of freeway basic segments, design and crash data of 640 segments are collected from different institutions. Three negative binomial (NB) regression models and three generalized negative binomial (GNB) regression models are built to prove that the interactive influence of explanatory variables plays an important role in fitting goodness. The effective use of the GNB model in analyzing the interactive influence of explanatory variables and predicting freeway basic segments is demonstrated. Among six models, the two models (one is the NB model and the other is the GNB model. ) which consider the interactive influence of the annual average daily traffic (AADT) and length are more reasonable for predicting results. Furthermore, a comprehensive study is carried out to prove that when considering the interactive influence, the NB and GNB models have almost the same fitting performance in estimating the crashes, among which the GNB model is slightly better for prediction performance. 展开更多
关键词 CRASH FREEWAY safety performance function( SPF interactive influence of explanatory variables generalized negative binomial (GNB)
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Water discharge variability of Changjiang(Yangtze) and Huanghe(Yellow) Rivers and its response to climatic changes 被引量:2
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作者 张喜林 范德江 +1 位作者 王厚杰 杨作升 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第6期1392-1405,共14页
Influences of large-scale climatic phenomena, such as the E1Nifio/La Nifia-Southem Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO), on the temporal variations of the annual water discharge at the Liji... Influences of large-scale climatic phenomena, such as the E1Nifio/La Nifia-Southem Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO), on the temporal variations of the annual water discharge at the Lijin station in the Huanghe (Yellow) River and at the Datong station in the Changjiang (Yangtze) River were examined. Using the empirical mode decomposition-maximum entropy spectral analysis (EMD- MESA) method, the 2- to 3-year, 8- to 14-year, and 23-year cyclical variations of the annual water discharge at the two stations were discovered. Based on the analysis results, the hydrological time series on the inter- annual to interdecadal scales were constructed. The results indicate that from 1950 to 2011, a significant downward trend occurred in the natural annual water discharge in Huanghe River. However, the changes in water discharge in Changjiang River basin exhibited a slightly upward trend. It indicated that the changes in the river discharge in the Huanghe basin were driven primarily by precipitation. Other factors, such as the precipitation over the Changjiang River tributaries, ice melt and evaporation contributed much more to the increase in the Changjiang River basin. Especially, the impacts of the inter-annual and inter-decadal climate oscillations such as ENSO and PDO could change the long-term patterns of precipitation over the basins of the two major rivers. Generally, low amounts of basin-wide precipitation on interannual to interdecadal scales over the two rivers corresponded to most of the warm ENSO events and the warm phases of the PDO, and vice versa. The positive phases of the PDO and ENSO could lead to reduced precipitation and consequently affect the long-term scale water discharges at the two rivers. 展开更多
关键词 water discharge Changjiang (Yangtze) River Huanghe (Yellow) River empirical modedecomposition maximum entropy spectral analysis large-scale climate factor
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Synthesis of nanostructured Mg_2FeH_6 hydride and hydrogen sorption properties of complex 被引量:1
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作者 李松林 汤盛龙 +2 位作者 刘燚 彭书科 崔建民 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第12期2281-2288,共8页
Reactive mechanical alloying(RMA)was carried out in a planetary ball mill for the synthesis of ternary hydride Mg2FeH6 for hydrogen storage.The formation mechanism of Mg2FeH6 in RMA process and the sorption properties... Reactive mechanical alloying(RMA)was carried out in a planetary ball mill for the synthesis of ternary hydride Mg2FeH6 for hydrogen storage.The formation mechanism of Mg2FeH6 in RMA process and the sorption properties of the products were investigated.The results show that Mg2FeH6 has a yield ratio around 80%,and a grain size below 10 nm in the powder synthesized by milling 3Mg+Fe mixture for 150 h under the hydrogen pressure of 1 MPa.The synthesized powder possesses a high hydrogen capacity and good sorption kinetics,and absorbs 4.42%(mass fraction)of hydrogen within 200 s at 623 K under the hydrogen pressure of 4.0 MPa.In releasing hydrogen at 653 K under 0.1 MPa,it desorbs 4.43%(mass fraction)of hydrogen within 2 000 s.The addition of Ti increases the hydrogen desorption rate of the complex in the initial 120 s of the desorption process. 展开更多
关键词 reactive mechanical alloying(RMA) metal hydride hydrogen storage material KINETICS fuel cell
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Event-based incremental updating of spatio-temporal database 被引量:10
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作者 周晓光 陈军 +2 位作者 蒋捷 朱建军 李志林 《Journal of Central South University of Technology》 2004年第2期192-198,共7页
Based on the relationship among the geographic events, spatial changes and the database operations, a new automatic (semi-automatic) incremental updating approach of spatio-temporal database (STDB) named as (event-bas... Based on the relationship among the geographic events, spatial changes and the database operations, a new automatic (semi-automatic) incremental updating approach of spatio-temporal database (STDB) named as (event-based) incremental updating (E-BIU) is proposed in this paper. At first, the relationship among the events, spatial changes and the database operations is analyzed, then a total architecture of E-BIU implementation is designed, which includes an event queue, three managers and two sets of rules, each component is presented in detail. The process of the E-BIU of master STDB is described successively. An example of building’s incremental updating is given to illustrate this approach at the end. The result shows that E-BIU is an efficient automatic updating approach for master STDB. 展开更多
关键词 incremental updating geographic event spatial change database operation MANAGER
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ENVIRONMENTAL CHANGE AND ITS IMPACTS ON HUMAN SETTLEMENT IN THE CHANGJIANG RIVER DELTA IN NEOLITHIC AGE 被引量:4
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作者 ZHANGQiang LIUChun-ling +1 位作者 ZHUCheng JIANGTong 《Chinese Geographical Science》 SCIE CSCD 2004年第3期239-244,共6页
Dating data, altitude of Neolithic sites, climatic changes from sedimentary records and previous research results were collected and analyzed to detect possible connections between climatic changes and human activitie... Dating data, altitude of Neolithic sites, climatic changes from sedimentary records and previous research results were collected and analyzed to detect possible connections between climatic changes and human activities in the Changjiang River Delta in the Neolithic Age. The results indicated that hydrological changes greatly impacted the human activities in the study region. Low-lying geomorphology made the floods and sea level changes become the important factors affecting human activities, especially the altitude change of human settlements. People usually moved to higher places during the periods characterized by high sea level and frequent floods to escape the negative influences from water body expansion, which resulted in cultural hiatus in certain profiles. However, some higher-altitude settlements were not the results of climatic changes but the results of social factors, such as religious ceremony and social status. Therefore, further research will be necessary for the degree and types of impacts of climatic changes on human activities in the study area at that time. 展开更多
关键词 Changjiang River Delta Neolithic Age human activities climatic events
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Evolution and meteorological causes of fine particulate explosive growth events in Beijing, China, from 2013 to 2017 被引量:2
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作者 SHI Shuzhen LIU Zirui +3 位作者 XU Zhongjun YANG Shuanghong LIU Jingda WANG Yuesi 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第1期55-62,共8页
Based on online observations of fine particulate matter(PM2.5) for five consecutive years from January 2013 to December 2017 in Beijing, combined with simultaneous measurement of gaseous precursors and meteorological ... Based on online observations of fine particulate matter(PM2.5) for five consecutive years from January 2013 to December 2017 in Beijing, combined with simultaneous measurement of gaseous precursors and meteorological parameters, the evolution and meteorological causes of fineparticle explosive growth(FPEG) events were analyzed. During the 5-year observation period,132 FPEG events were observed and these events were further divided into three types(3-, 6-, and 9-h events) according to their evolution duration. The majority of FPEG events were observed in winter under the conditions of higher gas precursor concentrations and unfavorable meteorological conditions. The average concentration of PM2.5 during winter FPEG events changed little from 2013 to 2016, whereas it decreased significantly in 2017, in accordance with the similar variation of gaseous species(SO2, NO2, and CO). In addition, the higher wind speeds and lowest relative humidity observed in 2017 were also conducive to the decrease in PM2.5. The evolutions of FPEG events and normal haze episodes were analyzed, revealing that the rate of increase in NO2 was much greater than that of SO2, suggesting more of a contribution from mobile sources than stationary sources. The polar Plot results suggest that the transportation from the southeast area of Beijing plays a major role in the formation of 3-h events, whereas local emissions is the main contributory factor for 9-h events and normal haze episodes. However, further quantitative analysis regarding the contributions of these factors is still needed. 展开更多
关键词 Fine-particle explosive growth events PM2.5 gaseous precursor meteorological factors BEIJING
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EVIDENCE FOR ABRUPT CLIMATIC CHANGES ON NORTHWESTERN MARGIN OF EAST ASIAN MONSOON REGION DURING LAST DEGLACIATION 被引量:2
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作者 QIANGMing-rui LISent 《Chinese Geographical Science》 SCIE CSCD 2004年第2期117-121,共5页
Based on investigations of the Zhongwei Nanshan aeolian section situated in the southeastern margin of Tengger Desert, carbon-14 and TL (thermoluminescence) dating results and paleoclimatic proxies such as magnetic su... Based on investigations of the Zhongwei Nanshan aeolian section situated in the southeastern margin of Tengger Desert, carbon-14 and TL (thermoluminescence) dating results and paleoclimatic proxies such as magnetic susceptibility and grain size, we inferred that the northwestern margin of East Asian monsoon region experienced abrupt climatic changes during the last deglaciation. Six oscillation events were identified: Oldest Dryas, Bolling, Older Dryas, Allerod, Intra-Allerod Cold Period (IACP) and Younger Dryas (YD). The summer monsoon was weaker during Oldest Dryas and Younger Dryas when the winter monsoon was stronger. However, during the B/A (Bolling/Allerod) period, the summer monsoon strengthened, reflected by magnetic susceptibility, when the winter monsoon also became strong, which is different from the paleoclimatic pattern established in the East Asian monsoon region. Furthermore, the summer monsoon was nearly in phase with the climate changes inferred from the oxygen isotopic records of Greenland ice cores. It could be speculated that the variations of the sea ice cover in the high latitudes of the North Hemisphere affected the high pressure of Asian continent and the changes of the winter monsoon inland. On the other hand, the sea ice cover variations might have indirectly caused the occurrence of ENSO events that has tightly been related to the summer monsoon in northwest margin of East Asian monsoon region. 展开更多
关键词 last deglaciation East Asian monsoon abrupt climatic changes
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Stable Isotopes in Precipitation and Atmospheric Moisture of Pailugou Catchment in Northwestern China′s Qilian Mountains 被引量:4
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作者 FENG Fang FENG Qi +2 位作者 LIU Xiande WU Jinkui LIU Wei 《Chinese Geographical Science》 SCIE CSCD 2017年第1期97-109,共13页
Hydrogen and oxygen isotopes in precipitation have been widely used as effective traces to investigate hydrological processes such as evaporation and atmospheric moisture source. This study analyzed δD and δ^(18)O o... Hydrogen and oxygen isotopes in precipitation have been widely used as effective traces to investigate hydrological processes such as evaporation and atmospheric moisture source. This study analyzed δD and δ^(18)O of precipitation in continuous event-based samples at three stations of Pailugou Catchment from November 2012 to December 2013. The δ^(18)O and δD values ranged from-32.32‰ to +3.23‰ and from-254.46‰ to +12.11‰, respectively. Results show that the δ^(18)O displayed a distinct seasonal variation, with enriched values occurring in summer and relatively depleted values in winter, respectively. There was a statistically significant positive correlation between the δ^(18)O and δD values and local surface air temperature at all the three stations. The nearest Global Network of Isotopes in Precipitation(GNIP) station(Zhangye), compared to the Meteoric Water Lines for this study, showed the obvious local evaporation effects with lower intercept and slope. Additionally, d-excess(δD- 8δ^(18)O) parameter in precipitation exhibited an anti-phase seasonal variability with the δ^(18)O. The 96-h back trajectories for each precipitation event using Hybrid Single Particle Lagrangian Integrated Trajectory(HYSPLIT) model indicated a dominant effect of westerly air masses in summer and the integrated influence of westerly and polar air masses in winter. 展开更多
关键词 meteoric precipitation δ^18O and δD d-excess moisture source Pailugou Catchment
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Impact of ENSO events on the interannual variability of Hadley circulation extents in boreal winter 被引量:2
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作者 GUO Yi-Peng LI Jian-Ping 《Advances in Climate Change Research》 SCIE CSCD 2016年第1期46-53,共8页
The interannual variability of the boreal winter Hadley circulation extents during the period of 1979e2014 and its links to El Ni^no-Southern Oscillation(ENSO) were investigated by using reanalysis datasets. Results s... The interannual variability of the boreal winter Hadley circulation extents during the period of 1979e2014 and its links to El Ni^no-Southern Oscillation(ENSO) were investigated by using reanalysis datasets. Results showed that the El Ni^no(La Ni^na) events can induce the shrinking(expansion) of Hadley circulation extent in the Southern Hemisphere. For the Northern Hemisphere, El Ni^no(La Ni^na) mainly leads to shrinking(expansion) of the Hadley circulation extent in the middle and lower troposphere and expansion(shrinking) of the Hadley circulation extent in the upper troposphere. The ENSO associated meridional temperature gradients have close relationship with the Hadley circulation extents in both Hemispheres. But in the Northern Hemisphere, the ENSO associated eddy momentum flux divergence plays more important role in affecting the Hadley circulation extent than the meridional temperature gradient because of the small local Rossby number. In the Southern Hemisphere, as the ENSO induced eddy momentum flux divergence is small, the meridional temperature gradient dominates the change of the Hadley circulation extent. 展开更多
关键词 Hadley circulation Extents Meridional temperature gradient ENSO
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