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论晚清文学的“事件化”--以“华工禁约”事件的文学书写为例
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作者 徐先智 《中国现代文学论丛》 2023年第4期254-270,共17页
晚清文学与舆论的关系十分密切,不过二者之间的关系是失衡的,文学在两者关系中处于被动的状态。晚清文学被舆论所规训,在创作题材、表现的观念与表达方式等方面,都会被某一现实舆论事件所强烈“吸引”,从而被动地介入对特定“事件”的表... 晚清文学与舆论的关系十分密切,不过二者之间的关系是失衡的,文学在两者关系中处于被动的状态。晚清文学被舆论所规训,在创作题材、表现的观念与表达方式等方面,都会被某一现实舆论事件所强烈“吸引”,从而被动地介入对特定“事件”的表达,形成一种“事件化”的特征。本文认为晚清文学在自身的内在价值上,一直处于一种不稳定的过渡状态,这一时期文学并未完成自身主体性的建立,从而导致文学容易被外部舆论事件所影响,缺乏相应的自主性。建立文学自身的主体性,对现实生活形成主动的“反映”,挣脱这种“事件化”的状态,则正是中国文学从古典走向现代所必须迈出的一步。 展开更多
关键词 晚清文学 “事件化” 华工禁约 文学主体性
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“情”动于“事”——战时街头剧的声音实践与情感动员
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作者 高菲 《汉语言文学研究》 CSSCI 2024年第4期23-32,共10页
全面抗战爆发后,为最大程度发挥街头剧的动员宣传效能,戏剧工作者们设计出了一种“事件化”的实践方案。此方案的核心在于以“声音”为方法,借助诉诸听觉的“说”“唱”实践,从根本上贴切民众的感觉和认知结构,在“情、理、事”之间开... 全面抗战爆发后,为最大程度发挥街头剧的动员宣传效能,戏剧工作者们设计出了一种“事件化”的实践方案。此方案的核心在于以“声音”为方法,借助诉诸听觉的“说”“唱”实践,从根本上贴切民众的感觉和认知结构,在“情、理、事”之间开掘出一关联机制,从而使民众在“弄假成真”的基础上产生情感共振,进而将之“引诱到一个实际的行动中去”,由事件的“旁观者”转换为“发声者”。以《放下你的鞭子》的一次演出实况为例,在同演员一起歌唱、呼喊口号的过程中,大众主体经历了从“家”之情感共鸣到“国”之伦理自觉的深刻转变,最终成为抗日救亡运动中坚不可摧的力量。 展开更多
关键词 街头剧 “事件化” 声音实践 情动主体
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Wet deposition and scavenging ratio of air pollutants during an extreme rainstorm in the North China Plain 被引量:1
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作者 Pan Yue-Peng Zhu Xia-Ying +6 位作者 Tian Shi-Li Wang Li-Li Zhang Guo-Zhong Zhou Yan-Bo Xu Peng Hu Bo Wang Yue-Si 《Atmospheric and Oceanic Science Letters》 CSCD 2017年第5期348-353,共6页
Atmospheric wet deposition plays an important role in the supply of nutrients and toxic substances to terrestrial and aquatic environments. Although long-term(e.g. annual, multi-year) wet deposition is recorded well... Atmospheric wet deposition plays an important role in the supply of nutrients and toxic substances to terrestrial and aquatic environments. Although long-term(e.g. annual, multi-year) wet deposition is recorded well, pronounced and short-term changes in precipitation chemistry are less well investigated. In the present study, the precipitation chemistry and scavenging ratio of air pollutants were observed during an extreme torrential rain event(325.6 mm at the observation site) that occurred over 19–21 July 2016 in the North China Plain(NCP). The scavenging ratio of particles showed a similar spatial distribution to that of the precipitation amount in the NCP, indicating the efficient removal of particulate matter due to the large amount and precipitation intensity of the storm. In addition, the scavenging ratio of water soluble ions was larger than that of organics and gaseous pollutants such as SO_2 and NO_2, likely due to their differences in water solubility.Consequently, raindrops incorporated more aerosol sulfate than gaseous compounds. Due to the heavy precipitation amount, almost all species in rainwater during this storm showed their lowest concentration but the highest flux compared with other rain events, indicating an important role played by this storm in terms of the substances received by the terrestrial and marine ecosystems of the region. However, the contribution of this storm to the annual chemical flux was lower than that of precipitation amount, indicating that the atmospheric compounds were scavenged below-cloud first and were then diluted by the cloud/rainwater. Future studies are needed in the context of the occurrence of extreme rainfall events in the NCP from the perspective of climate variability. 展开更多
关键词 Extreme precipitation event rain chemistry wet deposition
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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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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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A Possible Interpretation of Burst-Like Characteristics of Explosive Events 被引量:1
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作者 FANQuan-Lin FENGXue-Shang XIANGChang-Qing 《Communications in Theoretical Physics》 SCIE CAS CSCD 2004年第5期790-794,共5页
Explosive events have been observed to occur consecutively in bursts at intermittent locations along theboundary near the opposite polarity. The aim of the present paper is to explore a possible mechanism to interpret... Explosive events have been observed to occur consecutively in bursts at intermittent locations along theboundary near the opposite polarity. The aim of the present paper is to explore a possible mechanism to interpret thisburst-like characteristic of explosive events. The 2D magnetohydrodynamic (MHD) numerical simulations with resistivityhave been carried out to reproduce the intermittent spatial-temporal magnetic reconnection events taking place along thelong, compressible current sheet. The observed density enhancements in previously published results have been verifiedto be associated to magnetic reconnection sites. Late observational evidences, which support present attempts, have alsobeen found, at least in morphological evolution of the consecutive explosive events. 展开更多
关键词 explosive events magnetic reconnection MAGNETOHYDRODYNAMICS solar transition region numerical simulation
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Useful Precursor Weather Conditions for Hail-Event Forecasting in the Beijing-Tianjin Region 被引量:1
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作者 YUAN Wei SUN Jian-Qi +2 位作者 YU Xiao-Ding CHEN Ming-Xuan XIAO Xian 《Atmospheric and Oceanic Science Letters》 2011年第3期168-172,共5页
Hail is one of the important weather disasters that affects the Beijing-Tianjin(BT) region.To better understand and to improve the forecasting of hail events over the BT region,the precursor weather conditions for hai... Hail is one of the important weather disasters that affects the Beijing-Tianjin(BT) region.To better understand and to improve the forecasting of hail events over the BT region,the precursor weather conditions for hail based on 30 previous hail events were derived.It was found that the high-level trough and low-level cold front over the Mongolian region,the accumulated convective available potential energy,the decrease of the height of the 0℃-isotherm in the morning,and the persistence and intensification of these factors from morning to afternoon are valuable clues for forecasting the occurrence of hail events over the BT region. 展开更多
关键词 hail event Beijing-Tianjin region forecasting
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Heat center of the western Pacific warm pool 被引量:4
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作者 HU Shijian Hu Dunxin 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2012年第1期169-176,共8页
A heat center (HC) of the western Pacific warm pool (WPWP) is defined, its variability is examined, and a possible mechanism is discussed. Analysis and calculation of a temperature dataset from 1945-2006 show that... A heat center (HC) of the western Pacific warm pool (WPWP) is defined, its variability is examined, and a possible mechanism is discussed. Analysis and calculation of a temperature dataset from 1945-2006 show that the mean position of the HC during this period was near 0.4°S/169.0°E, at 38.0 m depth. From a time series of the HC, remarkable seasonal variability was found, mainly in the meridional and vertical directions. Interannual variabilities were dominant in the zonal and vertical directions. In addition, semiannual variation in the HC depth was discovered. The longitude of the HC varies with ENSO events, and its latitude is weakly related to ENSO on time scales shorter than a decade. The variation of the HC longitude leads the Nifio-3 index by about 3-4 months, and its depth lags the index for approximately 3 months. It is concluded that the HC depth results from a combination of its longitudinal and latitudinal variations. Low-pass-filtered time series reveal that the HC has moved eastward since the mid 1980s. 展开更多
关键词 western Pacific warm pool heat center VARIABILITY
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Epithelial-to-mesenchymal and mesenchymal-to-epithelial transitions in the colon 被引量:16
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作者 Ferenc Sipos Orsolya Galamb 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第7期601-608,共8页
Epithelial-to-mesenchymal and mesenchymal-to-epi- thelial transitions are well established biological events which have an important role in not just normal tissue and organ development, but in the pathogenesis of dis... Epithelial-to-mesenchymal and mesenchymal-to-epi- thelial transitions are well established biological events which have an important role in not just normal tissue and organ development, but in the pathogenesis of diseases. Increasing evidence has established their presence in the human colon during colorectal carcinogenesis and cancer invasion, chronic inflammation-related fibrosis and in the course of mucosal healing. A large body of evidence supports the role for transforming growth factor-13 and its downstream Smad signaling, the phosphatidylinositol 3'-kinase/Akt/mTOR axis, the Ras-mitogen-activated protein kinase/Snail/Slug and FOXC2 pathway, and Hedgehog signaling and microR- NAs in the development of colorectal cancers via epi- thelial-to-mesenchymal transition. C-met and Frizzled-7, among others, seem to be the principle effectors of mesenchymal-to-epithelial transition, hence have a role not just in mucosal regeneration but in the progression of colonic wall fibrosis. Here we discuss a role for these pathways in the initiation and development of the transition events. A better understanding of their induction and regulation may lead to the identification of pathways and factors that could be potent therapeu- tic targets. The inhibition of epithelial-to-mesenchymal transition using mTOR kinase inhibitors targeting theATP binding pocket and which inhibit both mTORC1 and mTORC2, RNA aptamers or peptide mimetics, such as a Wnt5A-mimetic, may all be useful in both cancer treatment and delaying fibrosis, while the induction of mesenchymal-to-epithelial transition in induced pluripotent stem cells may enhance epithelial healing in the case of severe mucosal damage. The preliminary results of the current studies are promising, but more clinical investigations are needed to develop new and safe therapeutic strategies for diseases of the colon. 展开更多
关键词 Epithelial-to-mesenchymal transition Mesen-chymal-to-epithelial transition Colorectal cancer FIBROSIS Mucosal healing
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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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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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The Holocene warm-humid phases in the North China Plain as recorded by multi-proxy records 被引量:1
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作者 崔建新 周尚哲 常宏 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2009年第1期147-161,共15页
The grain size and palinology of sediment and the frequency of ^14C dada provide an integrated reconstruction of the Holocene warm-humid phases of the North China Plain. Two clear intense and long-lasting warm-humid p... The grain size and palinology of sediment and the frequency of ^14C dada provide an integrated reconstruction of the Holocene warm-humid phases of the North China Plain. Two clear intense and long-lasting warm-humid phases were identified by comprehensive research in this region. The first phase was dated back to the early Holocene (9 000-7 000 a BP), and the second was centered at 5 000-3 000 a BP. The warm-humid episode between 9 000 and 7 000 a BP was also recognized at other sites showing global climatic trends rather than local events. Compared with the concern to the warm-humid phase of the early Holocene, the second one was not paid enough attention in the last few decades. The compilation of the Holocene paleoclimate data suggests that perhaps the second warm-humid phase was pervasive in monsoon region of China. In perspective of environmental archaeology, much attention should be devoted to it, because the flourish and adaptation of the Neolithic cultures and the building up of the first state seem to corresponding to the general warm-humid climatic conditions of this period. In addition, a warm-humid interval at 7 20045 500 a BP was recognized by the grain size data from three sites. However, this warm-humid event was not shown in pollen assemblage and temporal distribution of ^14C data. Perhaps, the resolution for climatic reconstruction from pollen and temporal distribution of ^14C data cited here is relatively low and small-amplitude and short-period climatic events cannot be well reflected by the data. Due to the difference in locality and elevation of sampling site, as well as in resolution of proxy records, it is difficult to make precise correlation. Further work is needed in the future. 展开更多
关键词 HOLOCENE grain size POLLEN radiocarbon dating warm-humid phases
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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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Characteristics and Changes of Cold Surge Events over China during 1960-2007 被引量:14
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作者 DING Ting QIAN Wei-Hong YAN Zhong-Wei 《Atmospheric and Oceanic Science Letters》 2009年第6期339-344,共6页
This paper demonstrates regional characteristics, a long-term decreasing trend, and decadal variations in the frequency of cold surge events based on daily mean temperature and daily minimum temperature data in China&... This paper demonstrates regional characteristics, a long-term decreasing trend, and decadal variations in the frequency of cold surge events based on daily mean temperature and daily minimum temperature data in China's Mainland from 1960 to 2008. During these 48 years four high frequency centers of cold surge events were located in Xinjiang, central North China, northeast China, and southeast China. A main frequency peak of cold surge events occurs in autumn for the four regions and another peak is detected in spring over northeast China and southeast China. The regional pattern of cold surge frequencies is in accordance with the perturbation kinetic energy distribution in October December, January, and February April. The long-term decreasing trend ( 0.2 times/decade) of cold surge frequencies in northeast China and decadal variations in China are related to the variations of the temperature difference between southern and northern China in the winter monsoon season; these variations are due to the significant rising of winter temperatures in high latitudes. 展开更多
关键词 cold surge extreme event TEMPERATURE climate change TREND
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Catalytic Cracking of Cycloparaffins Admixed with Olefins:2. Single-Event Microkinetic(SEMK) Assessment 被引量:1
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作者 Xue Gaoping Weng Huixin +1 位作者 Joris W.Thybaut Guy B.Marin 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2014年第2期84-90,共7页
The developed SEMK model is used to provide an insight into the contribution of individual reactions in the cracking of methylcyclohexane as well as the site coverage by various carbenium ions. The preferred reaction ... The developed SEMK model is used to provide an insight into the contribution of individual reactions in the cracking of methylcyclohexane as well as the site coverage by various carbenium ions. The preferred reaction pathways for the conversion of methylcyclohexane are hydride transfer reactions followed by PCP-isomerizations, deprotonation and endocyclic β-scission, accounting for 61%, 22% and 12% of its disappearance, respectively, at 693 K and 30% conversion of methylcyclohexane. Protolysis plays a minor role in the cracking of methylcyclohexane. Once cyclic diolefins are formed, all of them can be instantaneously transformed to aromatics, which are easily interconverted via disproportionation. Judging from the carbenium ion concentrations it is evident that, at the investigated operating conditions, less than 5% of the acid sites are covered by carbenium ions, less than 2% of which corresponds to cyclic type species including allylic ones. 展开更多
关键词 catalytic cracking single-event microkinetic model cycloparaffin OLEFIN site coverage by carbenium ions
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Sub seasonal variations of weak stratospheric polar vortex in December and its impact on Eurasian air temperature 被引量:1
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作者 PENG Cheng FAN Ke DAI Haixia 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第5期369-375,共7页
Weak stratospheric polar vortex(WPV)events during winter months were investigated.WPV events were identified as being weakest in December,accompanied by the most dramatic increase in geopotential height over the polar... Weak stratospheric polar vortex(WPV)events during winter months were investigated.WPV events were identified as being weakest in December,accompanied by the most dramatic increase in geopotential height over the polar region.After the onset of a December WPV event,the dynamic processes influencing Eurasian temperature can be split into two separate periods.Period I(lag of 0-25 days)is referred to as the stratosphere-troposphere interactions period,as it is mainly characterized by stratospheric signals propagating downwards.In Period I,a stratospheric negative Northern Annular Mode(NAM)pattern associated with the WPV propagates downwards,inducing a negative NAM in the troposphere.The anomalous low centers over the Mediterranean and North Pacific bring cold advection to northern Eurasia,resulting in a north-cold-south-warm dipole pattern over Eurasia.The zero line between negative and positive temperature anomalies moves southwards during days 5-20.Stratospheric cold anomalies at midlatitudes propagate downwards to high latitudes in the troposphere and contribute to the dipole structure.During PeriodⅡ(lag of 25-40 days),as downward signals from the stratosphere have vanished,the dynamic processes mainly take place within the troposphere.Specifically,a wave train is initiated from the North Atlantic region to northern Europe.The propagation of wave activity flux intensifies a cyclonic anomaly over northern Europe,which brings cold advection to Scandinavia and warm advection to central Asia.Therefore,a northwest-cold-southeast-warm dipole structure occupies Eurasia and migrates southeastwards during this period. 展开更多
关键词 Stratospheric polar vortex weak stratospheric polar vortex events in December subseasonal variability stratosphere-troposphere interaction winter Eurasian air temperature(0-40 days)
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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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Sentiment classification model for bullet screen based on self-attention mechanism 被引量:2
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作者 ZHAO Shuxu LIU Lijiao MA Qinjing 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2021年第4期479-488,共10页
With the development of short video industry,video and bullet screen have become important ways to spread public opinions.Public attitudes can be timely obtained through emotional analysis on bullet screen,which can a... With the development of short video industry,video and bullet screen have become important ways to spread public opinions.Public attitudes can be timely obtained through emotional analysis on bullet screen,which can also reduce difficulties in management of online public opinions.A convolutional neural network model based on multi-head attention is proposed to solve the problem of how to effectively model relations among words and identify key words in emotion classification tasks with short text contents and lack of complete context information.Firstly,encode word positions so that order information of input sequences can be used by the model.Secondly,use a multi-head attention mechanism to obtain semantic expressions in different subspaces,effectively capture internal relevance and enhance dependent relationships among words,as well as highlight emotional weights of key emotional words.Then a dilated convolution is used to increase the receptive field and extract more features.On this basis,the above multi-attention mechanism is combined with a convolutional neural network to model and analyze the seven emotional categories of bullet screens.Testing from perspectives of model and dataset,experimental results can validate effectiveness of our approach.Finally,emotions of bullet screens are visualized to provide data supports for hot event controls and other fields. 展开更多
关键词 bullet screen text sentiment classification self-attention mechanism visual analysis hot events control
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Improvements in seismic event locations in a deep western U.S. coal mine using tomographic velocity models and an evolutionary search algorithm 被引量:7
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作者 LURKA Adam SWANSON Peter 《Mining Science and Technology》 EI CAS 2009年第5期599-603,共5页
Methods of improving seismic event locations were investigated as part of a research study aimed at reducing ground control safety hazards. Seismic event waveforms collected with a 23-station three-dimensional sensor ... Methods of improving seismic event locations were investigated as part of a research study aimed at reducing ground control safety hazards. Seismic event waveforms collected with a 23-station three-dimensional sensor array during longwall coal mining provide the data set used in the analyses. A spatially variable seismic velocity model is constructed using seismic event sources in a passive tomographic method. The resulting three-dimensional velocity model is used to relocate seismic event positions. An evolutionary optimization algorithm is implemented and used in both the velocity model development and in seeking improved event location solutions. Results obtained using the different velocity models are compared. The combination of the tomographic velocity model development and evolutionary search algorithm provides improvement to the event locations. 展开更多
关键词 seismic event location tomographic velocity model an evolutionary search algorithm
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Emergency Logistics and Standardization
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作者 Ren Yan 《China Standardization》 2009年第2期6-9,共4页
Emergency logistics are complex systems engineering operations.Standardizationis the solution to establishing a successful emergency logistics framework.Standardized systems of emergency logistics can be used to tackl... Emergency logistics are complex systems engineering operations.Standardizationis the solution to establishing a successful emergency logistics framework.Standardized systems of emergency logistics can be used to tackle sudden events anddisasters,to minimize disaster loss and to promote a healthy development of emergencylogistics in China. 展开更多
关键词 Emergency Logistics STANDARDIZATION
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