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“灾难片”类型下的“中国故事”——电影《天火》分析
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作者 任晟姝 张萌 《艺苑》 2020年第3期20-22,共3页
国产灾难类型电影《天火》,在叙事模式上严格遵循灾难片创作套路,在情感线索上积极回应社会痛点,在剧作主题上尝试突围创新,有效探索了“灾难类型策略”与“讲好中国故事”的逻辑自洽与有机平衡。
关键词 灾难类型片 《天火》 叙事模式 情感线索 主题创新
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悖论中的隐喻——评阿来长篇小说《天火》 被引量:2
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作者 翁礼明 《当代文坛》 CSSCI 2005年第5期21-23,共3页
关键词 悖论 隐喻 阿来 长篇小说 《天火》 少数民族文学研究
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人性原生态的多重显现——读阿来的长篇小说《天火》
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作者 吴星华 《巢湖学院学报》 2005年第5期123-126,共4页
《天火》以凝重而不乏诗意,现实而略具魔幻的笔调多方位展示了一幅以文革为底(背景)的人性之图,拥有普遍的历史感和普遍的人性指向。阿来是要通过权力来揭示人性的秘密,多方位呈现人性的原生态,不仅包括人性在强大权力背景下的扭曲、异... 《天火》以凝重而不乏诗意,现实而略具魔幻的笔调多方位展示了一幅以文革为底(背景)的人性之图,拥有普遍的历史感和普遍的人性指向。阿来是要通过权力来揭示人性的秘密,多方位呈现人性的原生态,不仅包括人性在强大权力背景下的扭曲、异化,更有尚未泯灭的人性之美、纯净心灵、高尚精神。 展开更多
关键词 《天火》 人性 权力
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Effects of fire disturbance on the forest structure and succession in the natural broad-leaved/Korean pine forest 被引量:7
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作者 刘丽娟 葛建平 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第4期269-274,共6页
Investigations on charcoal in the soil, fire-scarred trees, stand composition, forest structure as well as regeneration status were carried out in the natural broad-leaved/Korean pine (Pinus koraiensis) forest after f... Investigations on charcoal in the soil, fire-scarred trees, stand composition, forest structure as well as regeneration status were carried out in the natural broad-leaved/Korean pine (Pinus koraiensis) forest after fire disturbance at Liangshui Nature Reserve on the mid-north of Xiaoxingan Mountains from 1990 to 1992, and the ecological effects of fire disturbance on the formation and succession of this kind of forest were analyzed according to the survey results. The average depth of charcoal in the soil was related to the timing of the fire. According to the characteristic of fire-scarred trees, the dynamic map of the fire behavior was drawn onto the topographic map. It showed that the dimension and extent of the fire disturbance was closely related with site conditions. Fire disturbance only led to a significant difference in stand composition and diameter class structure for the stands at different locations, rather than completely destroying the forest. After fire disturbance, the horizontal community structure was a mosaic of different patches, which were made up of different deciduous species or different sizes of Korean pines, and the succession trend of each patch was also different. In the sites with the heavy fire disturbance, the intolerant hardwood species were dominant, and there were a large number of regenerative Korean pine saplings under the canopy. In the moderate -disturbed sites, the tolerant hardwood species were dominant, and a small number of large size Korean pines still survived. In the light-disturbed sites, large size Korean pines were dominant. 展开更多
关键词 Pinus koraiensis Natural forest Fire disturbance SUCCESSION
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天火
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作者 假面 速水上(图) 《作家天地》 2010年第10期40-53,共14页
“两个月前的一个夜晚。我合上了电脑。一头栽倒在床上,但是缠绕在我心中的困扰却久久不能散去。
关键词 小说 文学作品 现代文学 《天火》
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Structure changes and succession dynamic of the natural secondary forest after severe fire interference 被引量:2
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作者 刘滨凡 刘广菊 王志成 《Journal of Forestry Research》 SCIE CAS CSCD 2009年第2期123-130,I0002,共9页
The structure and dynamic succession law of natural secondary forest after severe fire interference in recent 20 years were studied by adopting the method of deducing time series from the spatial sequence of vegetatio... The structure and dynamic succession law of natural secondary forest after severe fire interference in recent 20 years were studied by adopting the method of deducing time series from the spatial sequence of vegetation in Heihe region, Heilongjiang, China. Two typical and widely distributed forest types in the study area, namely forest type A and forest type B, were selected as study subjects. Forest type A is pure broadleaf forest or broadleaf mixed forest mainly composing of superior Betula platyphylla and Populus davidiana in the area with gradient 〈25°, while forest type B is pure forest or mixed forest composing of superior Quercus mongolica and Betula davurica in the area with gradient 〉25°. Species richness, vegetation coverage, important value, and similarity index of commtmity in different layers (Herb, shrub, small tree, and arbor layers) were investigated and analyzed for the two typical forests. The results show that after fire interference, the species richness and coverage in each layer in forest type A were higher than that in forest type B. Both for forest type A and B, with elapse of post-fire years, the species richness and coverage of herbs and shrubs showed a decline tendency, while those of arbor layer present a rising tendency. Through comparison of the important values of species in each layer and analysis of community structure changes, the dynamic process of post-fire vegetation succession for forest type A and B was separately determined. Post-fire 80 years' succession tendency of forest type A is B. platyphylla and Larix gmelinii mixed forest. Its shrub layer is mainly composed of Corylus heterophylla and Vaccinium uliginosum, and herb layer is dominated by Carex tristachya, Athyrium multidentatum, and Pyrola incarnate; whereas, the post-fire 80 years' succession of forest type B is Q. mongolica and B. davurica mixed forest. Its shrub layer is mainly composed of lespedeza bicolar and corylus heterophylla and herb layer is dominated by Carex tristachya, Asparagus densiflorus, and Hemerocallis minor. 展开更多
关键词 natural secondary forest vegetation succession fire interference burned areas species richness important value similarity index succession law.
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Feng Jiasheng’s Diagrams of Iron Bombs(Huopao)and Beyond:On the Academic Significance of the Southern Song Iron Bombs(Huopao)Unearthed in Chongqing 被引量:3
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作者 Zhong Shaoyi 《Chinese Annals of History of Science and Technology》 2019年第1期62-73,共12页
The world’s earliest bomb with an iron casing,the iron huopao鐵火砲(cast-iron bomb,also referred to as zhentian lei震天雷,literally“thunder-crash bomb”),is one of the most important inventions of ancient China rela... The world’s earliest bomb with an iron casing,the iron huopao鐵火砲(cast-iron bomb,also referred to as zhentian lei震天雷,literally“thunder-crash bomb”),is one of the most important inventions of ancient China relating to gunpowder and firearms.Until recently,however,academics were not able to conduct substantial research on the topic,as no actual remains of a huopao had yet been found.Since 2013,in the excavation of two sites of Southern Song ancient cities(Diaoyu Fortress and Baidicheng)in Chongqing,archaeologists from the Chongqing Cultural Heritage Research Institute have discovered a number of iron huopao of the Southern Song dynasty.This finding not only provides first-hand material for research on the history of the invention of gunpowder and firearms,which has always been lacking,but also offers new physical evidence for an exploration of the history of war and the military history of the thirteenth century(in particular the Mongol-Song war),and is thus historically significant. 展开更多
关键词 iron huopao(bombs) zhentian lei history of firearms and gunpowder the Mongol-Song war Möngke Khan Diaoyu Fortress
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Spatial and temporal variability of open biomass burning in Northeast China from 2003 to 2017 被引量:4
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作者 WANG Lili JIN Xin +4 位作者 WANG Qinglu MAO Huiqin LIU Qiyang WENG Guoqing WANG Yuesi 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第3期240-247,共8页
Open biomass burning(OBB)has a significant impact on the heavy haze pollution in Northeast China(NEC)in recent years,which requires the investigation of the spatiotemporal variations of OBB with different vegetation t... Open biomass burning(OBB)has a significant impact on the heavy haze pollution in Northeast China(NEC)in recent years,which requires the investigation of the spatiotemporal variations of OBB with different vegetation types to better monitor and control OBB in NEC.The MODIS C6 fire and land cover products,together with the emissions inventory from the Global Fire Assimilation System,were used in this study.The changes in the total number of MODIS fire points in NEC from 2003 to 2017 demonstrated a fluctuating but generally rising trend,with a peak during 2013–2017.Most fire points concentrated in two key periods,i.e.March–April(37%)and October–November(46%).The total number of crop residue burnings in March–April was basically slightly fluctuating and increased sharply from 2013,whilst the number in October–November had a fluctuating and upward trend until 2015,when a decline appeared.The amount of OBB in March–April was higher than that in October–November during 2016–17.OBB in Heilongjiang Province comprised a major proportion of all fires,which accounted for 70.7%from 2003 to 2017;however,the proportion was only 66.2%during 2013–2017.The largest proportion of all fires was in cropland(90.8%),then forest(5.3%)and grassland(3.1%).The cumulative emissions of fine particulate matter,nitrogen oxides,and ammonia from agricultural open burning in NEC reached 78.43 Gg,24.9 Gg,and 13.7 Gg for March–April during 2013–17,respectively,which were close to those in October–November. 展开更多
关键词 Open biomass burning MODIS Northeast China open agricultural residual burning
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Analysis of Tianchi volcano activity in Changbai Mountain,NE China 被引量:8
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作者 LIU Guoming YANG Jingkui +1 位作者 WANG Lijuan SUN Jicai 《Global Geology》 2011年第1期44-53,共10页
Changbaishan volcano is the largest potential eruptive volcano in China.In this paper,seismic activity,horizontal displacement,vertical displacement and the fluid geochemistry data acquiring from Changbaishan Tianchi ... Changbaishan volcano is the largest potential eruptive volcano in China.In this paper,seismic activity,horizontal displacement,vertical displacement and the fluid geochemistry data acquiring from Changbaishan Tianchi Volcano Observatory(TVO) in recent years are analyzed.The authors discussed the ability for the Changbaishan volcanic seismic monitoring and active level of Changbaishan volcano in recent years based on the fundamental monitoring results.The results show that Changbaishan volcano has experienced an unrest episode from 2002 to 2005,but its active level recovers to the background now. 展开更多
关键词 VOLCANO volcanic event EARTHQUAKE Changbai Mountain
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Heating Stage Experimental Study of Melt Inclusions in Feldspars from Three Holocene Eruptions of Changbaishan Tianchi Volcano 被引量:1
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作者 Li Ni Nicole Metrich Fan Qicheng 《Earthquake Research in China》 2008年第2期153-163,共11页
There occurred several eruptions from Changbaishan Tianchi volcano in Holocene, and at least three of them were believed to be true according to the formal studies. The products of three eruptions were yellow comendit... There occurred several eruptions from Changbaishan Tianchi volcano in Holocene, and at least three of them were believed to be true according to the formal studies. The products of three eruptions were yellow comenditic pumice of - 5000a B.P. (Eruption Ⅰ ), gray comenditic pumice and pyroclastic flow of - 1000a B.P. ( Eruption II, i.e. the millennium explosive eruption), black trachy pumice and welded tuff of - 300a B.P. ( Eruption Ⅲ ) respectively. There were a large number of melt inclusions found in phenocrysts, which differ in size and color. The Leitz 1350 heating stage experiments for melt inclusions in host feldspars from three Holocene eruptions of Changbaishan Tianchi volcano imply that there were little differences between the homogenization temperatures of melt inclusions from Eruptions Ⅰ and Ⅲ, whereas it was rather complicated for Eruption H, i.e. there might be two kinds of melt with different homogenization temperature periods, which gave the evidence for the assumption that the explosive millennium eruption of Tianchi volcano was triggered by injection and mixing of two different magmas. The experimental results also indicate that ( 1 ) small melt inclusion is easy to be homogenized, while the large one, especially the one with lots of daughter crystals, is rather difficult to be homogenized; (2) homogenization temperature closely correlates with the size of melt inclusion within host crystal, with the temperature point switching from high heating rate to low heating rate, and correlates with whether it is the first time to obtain homogenization as well; and (3) a melt inclusion can get different homogenization temperatures when it is repeatedly heated. Even more, the next homogenization temperature is usually higher than the former one, which testifies the phenomenon that hydrogen migration occurs during repeated heating. 展开更多
关键词 Changbaishan Tianchi volcano Alkaline feldspar Melt inclusion Heating stage Homogenization temperature
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Advances in Large-eddy Simulation of Two-phase Combustion (I) LES of Spray Combustion 被引量:2
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作者 周力行 李科 王方 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第2期205-211,共7页
Spray combustion is widely used in power, transportation, chemical and metallurgical, iron and steel making, aeronautical and astronautical engineering. In recent years, large-eddy simulation (LES) becomes more and mo... Spray combustion is widely used in power, transportation, chemical and metallurgical, iron and steel making, aeronautical and astronautical engineering. In recent years, large-eddy simulation (LES) becomes more and more attractive, because it can give the instantaneous flow and flame structures, and may give more accurate statistical results than the Reynolds averaged Navier-Stokes (RANS) modeling. In this paper, the present status of the studies on LES of spray combustion is reviewed, and the future research needs are discussed. 展开更多
关键词 spray combustion large-eddy simulation sub-gnd scale model
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THE RELATIONSHIP OF THE PRECEDING WINTER MJO ACTIVITIES AND THE SUMMER PRECIPITATION IN YANGTZE-HUAIHE RIVER BASIN OF CHINA 被引量:4
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作者 李汀 琚建华 甘薇薇 《Journal of Tropical Meteorology》 SCIE 2012年第1期32-44,共13页
The first two series(RMM1 and RMM2) of RMM Index(all-Season Real-time Multivariate MJO Index) are computed to obtain the interannual variation of the preceding winter(preceding December to current February) MJO streng... The first two series(RMM1 and RMM2) of RMM Index(all-Season Real-time Multivariate MJO Index) are computed to obtain the interannual variation of the preceding winter(preceding December to current February) MJO strength,according to which active(or inactive) years of preceding winter MJO are divided.By utilizing the data provided by NCEP/NCAR,CMAP and China's 160 stations from 1979 to 2008,we studied the preceding winter MJO strength and discovered that the summer precipitation in the basin are of significantly negative correlation,i.e.when the preceding winter MJO is relatively active,the summer precipitation in the basin decreases,and vise verse.We also analyzed the causes.When the preceding winter MJO is relatively active,its release of potential heat facilities Inter-Tropical Convergence Zone(ITCZ) to strengthen and locate northward in winter and propagate northeastward.This abnormal situation lasts from winter to summer.In mid-May,ITCZ jumps northward to the South China Sea,the western Pacific subtropical high withdraws eastward,and the South China Sea summer monsoon sets off and strengthens.In summer,ITCZ propagates to South China Sea-subtropical western Pacific,the zonal circulation of subtropical Pacific strengthens,and a local meridional circulation of the South China Sea to the basin area forms,giving rise to the East Asia Pacific teleconnection wave-train.An East Asian monsoon trough and the Meiyu front show opposite features from south to north,the East Asian summer monsoon strengthens and advances northward.As a result,the summer monsoon is weakened as the basin is controlled by the subtropical high continually,with less rain in summer.On the contrary,when the preceding winter MJO is inactive,ITCZ weakens and is located southward,the subtropical high is located southward in summer,and the basin is in a region of ascending airflow with prevailing southwest wind.The East Asian monsoon trough and EASM weaken so that summer monsoon is reduced in the basin where precipitation increases. 展开更多
关键词 winter MJO summer precipitation in the basin ITCZ East Asia wave train East Asian Summer Monsoon
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Facies-controlled volcanic reservoirs of northern Songliao Basin, NE China 被引量:6
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作者 WANG Pu-jun HOU Qi-jun +3 位作者 SHU Ping HUANG Yu-long GUO Zhen-hua LI Jin-long 《Journal of Geoscientific Research in Northeast Asia》 2005年第1期72-77,共6页
Volcanic rocks of the late Mesozoic are very important reservoirs for the commercial natural gases including hydrocarbon, carbon dioxide and rare gases in the northern Songliao Basin. The reservoir volcanic rocks incl... Volcanic rocks of the late Mesozoic are very important reservoirs for the commercial natural gases including hydrocarbon, carbon dioxide and rare gases in the northern Songliao Basin. The reservoir volcanic rocks include rhyolite, andesite, Wachyte, basalt and tuff. Facies of the volcanic rocks can be classified into 5 categories and 15 special types. Porosity and permeability of the volcanic reservoirs arc facies-controlled, Commercial reservoirs were commonly found among the following volcanic subfacics: volcanic neck (Ⅰ1), underground-explosive breccia (Ⅰ3), pyroclastic-bcaring lava flow (Ⅱ3), upper effusivc (Ⅲ3) and inner extrusive ones ( Ⅳ1). The best volcanic reservoirs arc generally evolved in the interbedded explosive and effusivc volcanics. Rhyolites show in general better reservoir features than other types of rocks do. 展开更多
关键词 Songliao Basin Cretaceous: volcanic facies natural gas reservoir
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Exergy Analysis and Retrofitting of Natural Gas-based Acetylene Process 被引量:5
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作者 王志方 郑丹星 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2008年第5期812-818,共7页
This article presents an acetylene production process by partial oxidation/combustion of natural gas. The thermodynamic performance and exergy analysis in the process are investigated using the flow-sheeting program A... This article presents an acetylene production process by partial oxidation/combustion of natural gas. The thermodynamic performance and exergy analysis in the process are investigated using the flow-sheeting program Aspen Plus. The results indicate that the most important destruction of exergy is found to occur in the reactor and water quenching scrubber, amounting to 8.23% and 10.39%, respectively, of the entire system. Based on the results of thermodynamic and exergy analysis, the acetylene reactor has been retrofitted. The improvement ratios of molar 02 to CH4 and molar CO to CN4 are 0.65 and 0.20, respectively. An improvement of the acetylene production system is proposed. Adopting the improvement operation conditions and using oil to realize the reaction heat recovery, the feedstock of natural gas is reduced by 9.88% and the exergy loss in the retrofitting process is decreased by 19.71% compared to the original process. 展开更多
关键词 ACETYLENE exergy analysis natural gas partial oxidation HYDROGEN
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Elementary analysis of data from Tianchi Volcano 被引量:1
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作者 LIUGuo-ming ZHANGHeng-rong KONGQing-jun WUCheng-zhi GUOFeng ZHANGChao-fan 《Journal of Geoscientific Research in Northeast Asia》 2004年第2期156-160,共5页
Tianchi Volcano is the largest potential erupticve volcano in China. Analyzing these data on seismic monitoring, deformation observation and water chemistry investigation gained from the Tianchi Volcano Observatory(TV... Tianchi Volcano is the largest potential erupticve volcano in China. Analyzing these data on seismic monitoring, deformation observation and water chemistry investigation gained from the Tianchi Volcano Observatory(TVO), the authors consider that the Tianchi Volcano is in going into a new flourishing time. 展开更多
关键词 Tianchi Volcano DEFORMATION earthquake swarm
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Reflectivity forward modeling and a CSSI method seismic inversion study of igneous intrusive area,coked area,and gas-enriched area located within a coal seam 被引量:18
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作者 XU Yong-zhong CUI Ruo-fei +3 位作者 HUANG Wei-chuan CHEN Tong-jun CHEN Shi-zhong DONG Shou-hua 《Mining Science and Technology》 EI CAS 2009年第4期457-462,共6页
We applied the reflectivity method and the constrained sparse spike inverse modeling(CSSI) method to the interpretation of coal field lithologic seismic data.After introducing the principles of these two methods we di... We applied the reflectivity method and the constrained sparse spike inverse modeling(CSSI) method to the interpretation of coal field lithologic seismic data.After introducing the principles of these two methods we discuss some parameters of a geological model involving possible gas enriched areas or intruded igneous rock.The geological model was constructed and a 60 Hz seismic response profile was obtained looking for igneous rock intrusion and coked areas of the coal seam using the reflectivity method.Starting from synthesized logging data from two wells and a synthesized seismic wavelet we calibrated the model to show accurate strata.Finally,we predicted the lithology within a 10 m igneous rock area,a 3 m coal seam area,and a coked area using the CSSI technique.The results show that the CSSI technique can identify hard to recognize lithologic features that normal profil-ing methods might miss.It can quantitatively analyze and evaluate the intrusive area,the coked area,and the gas-enriched area. 展开更多
关键词 CSSI reflectivity method igneous rock coal seam coked area gas-enriched area
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The Activity of Major Faults and the Hydrothermal Alteration Zone at Tianchi Volcano of Changbaishan
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作者 LiuMingjun GuMenglin +2 位作者 SunZhenguo WeiHaiquan JinBolu 《Earthquake Research in China》 2004年第3期253-262,共10页
It is found by field investigation that the near horizontal top surface of the brown or brick-red hydrothermal alteration zone varies obviously in elevation at different sections of the same layer on the caldera’s in... It is found by field investigation that the near horizontal top surface of the brown or brick-red hydrothermal alteration zone varies obviously in elevation at different sections of the same layer on the caldera’s inner wall of Tianchi, with that at the north section near the Tianwen Peak about 110 m higher than that at the south near the Jiangjun Peak in Korea. The top surface of the hydrothermal alteration zone can be taken as key horizon to tectonic movement. The difference indicates that the total uplift height of the NW wall of the Liudaogou-Tianchi-Jingfengshan fault, the principal fault trending NE at Tianchi, is bigger than that of the SE wall ever since the occurrence of hydrothermal alteration. This also explains why the topography in the northwest side of Tianchi is steeper and with more developed river system than in the southeast. The uplifting of the northeastern wall is bigger than that of the southwest along the principal NW-trend fault, namely, the Baishanzhen-Tianchi-Jince fault. It is observed from characters of hydrothermal alteration and the palaeoresiduum, that the recent vertical movement rate along the principal NE-trend fault is larger than that of the principal NW-trend fault. The two faults intersect at Tianchi, dividing the volcano into 4 blocks, with the uplift magnitudes decreasing successively in the order of the north, the west, the east and the south block. The biggest uplift of the north block corresponds well to the shallow magma batch in the north of Tianchi observed by DSS and telluric electromagnetic sounding, and etc. and they may be related with the causes. 展开更多
关键词 Tianchi volcano Major fault Caldera's inner wall Hydrothermal alteration Different uplift
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Geochemical Features of the Hubin Spring Gases from the Northern Caldera Lake of the Tianchi Volcano,Changbai Mountains
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作者 Gao Ling Shangguan Zhiguan +1 位作者 Wei Haiquan Zhao Ciping 《Earthquake Research in China》 2011年第3期370-377,共8页
This paper deals with geochemical features of gas emitted from the Hubin Springs. The Hubin Springs zone, a strong thermal emission zone, is are locatedd at the north edge of the Tianchi caldera lake. Very young depos... This paper deals with geochemical features of gas emitted from the Hubin Springs. The Hubin Springs zone, a strong thermal emission zone, is are locatedd at the north edge of the Tianchi caldera lake. Very young deposits with uncertain eruption date are found on the top area of the Tianwenfeng, which might have been formed in one of the recent eruptions or the Millennium Eruption. It is of significance to study the geochemistry features of the emitting gas from the Hubin Springs to understand the activities of the Tianchi Volcano. This paper systematically sampled and analyzed the gases emitted from the Hubin Springs and discussed their geochemistry features. The results show that there is a high content of deep derived gases, such as CO2, He, CH4 and Ar in Hubin Springs zone. The isotopic ratio of He lies between 4. 18 and 5. 95 Ra. The averaged mantle derived gas content calculated from the ^4He/2^20Ne ratio and He content reaches 67.1%. All these show that the Hubin Springs are located on a special belt of deep gases released in high intensity and large scale. The spatial distribution of Helium isotope is characterized by concavity, showing that this special area may be related to the volcanic edifice. It is highly possible that the released gases represent the residual gas samples of the latest eruptions from the Tianchi Volcano. However more detailed studies are demanded. 展开更多
关键词 Tianchi Volcano Hubin strong gas-release zone Gas geochemistry CRATER Residual gas
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Characteristics of S-wave Envelope Broadening in the Changbaishan Tianchi Volcano
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作者 Fan Xiaoping Li Qinghe +2 位作者 He Haibing Yang Congjie Jin Shumei 《Earthquake Research in China》 2010年第3期385-393,共9页
High-frequency S-wave seismogram envelopes of microearthquakes broaden with increasing travel distance,a phenomenon known as S-wave envelope broadening. Multiple forward scattering and diffraction for the random inhom... High-frequency S-wave seismogram envelopes of microearthquakes broaden with increasing travel distance,a phenomenon known as S-wave envelope broadening. Multiple forward scattering and diffraction for the random inhomogeneities along the seismic ray path are the main causes of S-wave envelope broadening,so the phenomenon of S-wave envelope broadening is used to study the inhomogeneity of the medium. The peak delay time of an S-wave,which is defined as the time lag from the direct S-wave onset to the maximum amplitude arrival of its envelope,is accepted to quantify S-wave envelope broadening. 204 small earthquake records in Changbaishan Tianchi volcano were analyzed by the S-wave envelope broadening algorithm. The results show that S-wave envelope broadening in the Changbaishan Tianchi volcano is obvious,and that the peak delay time of S-wave has a positive correlation with the hypocenter distance and frequency of the S-wave. The relationships between the S-wave peak delay time and the hypocenter distance for different frequency bands were obtained using the statistics method. The results are beneficial to the understanding of the S-wave envelope broadening phenomena and the quantitative research on the inhomogeneities of the crust medium in the Changbaishan Tianchi volcano region. 展开更多
关键词 Changbaishan Tianchi volcano S-wave envelope broadening Peak delay timeof S-waves
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Research Progress in Aerospace Vehicles Propelled by Rocket-Based Combined Cycle Engines
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作者 ZHANG Duo QIN Fei +1 位作者 WEI Xianggeng HE Guoqiang 《Aerospace China》 2016年第4期21-29,共9页
The research status on the development of RBCC engines and corresponding aerospace vehicles around the world was overviewed,and the technical and application characteristics of RBCC technology were summarized.New deve... The research status on the development of RBCC engines and corresponding aerospace vehicles around the world was overviewed,and the technical and application characteristics of RBCC technology were summarized.New development trends of combined cycle engines as well as space transportation were analyzed,and lastly,some suggestions on the development of RBCC and the relative aerospace vehicles were proposed. 展开更多
关键词 RBCC aerospace vehicle space transportation TSTO
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