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Periodic Signals of the Milky Way Concealed in Terrestrial Sedimentary Basin Fills and in Planetary Magmatism? 被引量:4
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作者 Heinz-Jürgen Brink 《International Journal of Geosciences》 2015年第8期831-845,共15页
Long periodic geodynamic processes with durations between 150 and 600 Million years appear to be in phase with similar galactic cycles, caused by the path of the solar system through the spiral arms of the Milky Way. ... Long periodic geodynamic processes with durations between 150 and 600 Million years appear to be in phase with similar galactic cycles, caused by the path of the solar system through the spiral arms of the Milky Way. This path is assumed by some authors to cause climate change due to cosmic ray fluctuations, affecting the cloud formation and the related albedo of the Earth, which periodically lead to glaciations every 150 Ma. With the glaciations, the sea level fluctuates accordingly. Subsequently, the varying sizes of shallow seas are causing periodic changes of the Moon’s?tidal dissipation, which affects presumably other geodynamic processes on the Earth. The Moon?may therefore synchronize directly or indirectly long periodic Phanerozoic cycles (sea level, orogeny, magmatism, sedimentation, etc.) with the Milky Way. As sea level fluctuations, orogeny, sedimentation and magmatism can be described as members of a geodynamic feedback system;no apparent reasons appear to be required to assign a cause of the cyclicity to agents outside of the?galactic-climatically synchronized Earth-Moon system. However, recent observations of young?volcanism on the near Earth terrestrial planets may require a new understanding. Magmatic/volcanic episodes on Venus, Mars and Mercury as well as on the Earth’s Moon are apparently contemporaneous thermal events accompanying increased magmatic/volcanic activities on the?Earth,?following a 300 myr cycle. Therefore, a collateral galactic thermal source within the Milky Way?appears to be needed that only affects the interior of the planets without any recognizable direct?effect on life and geology on the Earth. The search for such a source may lead to astrophysical?questions, related to a spiral arm affected distribution of dark energy, dark matter or even specific?neutrino sources. However, all possible astrophysical answers are outside of the author’s competence. 展开更多
关键词 Milky way SPIRAL ARMS Planets Sea Level MAGMATISM Climate change
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Research on the construction path of the megacity from the perspective of Nudge Theory:Empirical evidence of the“Park City”construction in Chengdu Tianfu New Area
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作者 Xiaoqin Xie Xinglong Gong Shaojie Pan 《Chinese Journal of Population,Resources and Environment》 2023年第3期163-171,共9页
The transformation of Chengdu Tianfu New Area,a state-level new district,from the first site of constructing the“Park City”to the representative of the“Park City”,contains a unique path of“Chinese Style Governanc... The transformation of Chengdu Tianfu New Area,a state-level new district,from the first site of constructing the“Park City”to the representative of the“Park City”,contains a unique path of“Chinese Style Governance”.To expand the diverse paths of constructing megacities,the current research references the nudge theory of behavioral science,adopts the extended case method,and takes Chengdu Tianfu New Area as a typical case to summarize the“nudge”path of“Party City”construction.The study found that the government achieves the lock-in effect by the priming mechanism and uses the nudge strategy of improving environment and guiding public opinion,thereby helping the people make free choices.It realizes the framework effect by the salience mechanism and uses the strategies of highlighting key information and optimizing information delivery methods,which directly affects the behavior of the public.It achieves the commitment effect by the comparison mechanism,including the horizontal comparison and vertical comparison strategies,and gradually realizes the policy goals.It realizes the social norm effect by the imitation mechanism and uses the strategies of creating peer pressure and playing celebrity effect,which in turn influence people’s choices.With the help of the“nudging”mechanism,the construction of the park city has realized the interactive cycle of“government output-citizen feedback”and achieved the goal of“making great change through small actions”.As a new behavioral intervention tool,“nudging”provides an alternative explanation for the construction of the park city in Tianfu New Area and opens up new ideas for the construction of megacities.This study concludes that the construction of megacities can achieve the goal of“common return”through different ways and provides practical inspiration for future urban construction. 展开更多
关键词 Behavior nudge MEGACITIES Common return through different ways Making great change through small actions
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Numerical investigation on detonation cell evolution in a channel with area-changing cross section 被引量:1
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作者 DENG Bo,HU ZongMin,TENG HongHui & JIANG ZongLin Key Laboratory of High Temperature Gas Dynamics,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100080,China 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第6期797-808,共12页
The two-dimensional cellular detonation propagating in a channel with area-changing cross section was numerically simulated with the dispersion-controlled dissipative scheme and a detailed chemical reaction model. Eff... The two-dimensional cellular detonation propagating in a channel with area-changing cross section was numerically simulated with the dispersion-controlled dissipative scheme and a detailed chemical reaction model. Effects of the flow ex-pansion and compression on the cellular detonation cell were investigated to illus-trate the mechanism of the transverse wave development and the cellular detona-tion cell evolution. By examining gas composition variations behind the leading shock,the chemical reaction rate,the reaction zone length,and thermodynamic parameters,two kinds of the abnormal detonation waves were identified. To explore their development mechanism,chemical reactions,reflected shocks and rarefac-tion waves were discussed,which interact with each other and affect the cellular detonation in different ways. 展开更多
关键词 DETONATION cells transverse waves detailed CHEMICAL REACTION model numerical simulation The two-dimensional CELLULAR DETONATION propagating in a channel with area- changing cross section was numerically simulated with the dispersion-controlled dissipative scheme and a detailed CHEMICAL REACTION model. Effects of the flow expansion and compression on the CELLULAR DETONATION CELL were investigated to illustrate the mechanism of the transverse wave development and the CELLULAR DETONATION CELL evolution. By examining gas composition variations behind the leading shock the CHEMICAL REACTION rate the REACTION zone length and thermodynamic parameters two kinds of the abnormal DETONATION WAVES were identified. To explore their development mechanism CHEMICAL reactions reflected shocks and rarefaction WAVES were discussed which interact with each other and affect the CELLULAR DETONATION in different ways. ……
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Bird community comparisons of four plantations and conservation concerns in South China 被引量:1
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作者 Fasheng ZOU Qiongfang YANG +2 位作者 Yongbiao LIN Guoliang XU Russell GREENBERG 《Integrative Zoology》 SCIE CSCD 2014年第1期97-106,共10页
Plantations of non-native,fast-growing trees are increasing in the tropics and subtropics,perhaps with negative consequences for the native avifauna.We studied bird diversity in 4 types of plantations in South China t... Plantations of non-native,fast-growing trees are increasing in the tropics and subtropics,perhaps with negative consequences for the native avifauna.We studied bird diversity in 4 types of plantations in South China to deter-mine which plantation types are especially detrimental,and compared our findings with studies in nearby natu-ral forests to assess the magnitude of the negative impact.A total of 57 species was recorded.The mean capture rate of understory birds was 1.7 individuals 100-net-h-1.Bird richness and capture rate were lower in plantations than in nearby natural forests.Babblers(Timaliidae),primarily forest-dependent species in South China,were particularly under-represented in plantations.Species richness,composition and bird density,particularly of un-derstory birds,differed between plantation types.Plantations of Schima,which is native to South China,had the highest species richness according to point count data.Plantations of Acacia(non-native)supported the highest understory species richness and produced the highest capture rate of understory birds,probably because of their complex structure and high arthropod abundance.If bird diversity is to be considered,we strongly recommend that future re-afforestation projects in South China should,as far as possible,use mixed native tree species,and especially Schima,ahead of the other species. 展开更多
关键词 babbler conservation bird community changing planting ways plantations tree species selection
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SIMULATION OF REGIONAL CLIMATE OVER CHINA WITH CHINESE REGIONAL CLIMATE MODEL
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作者 李维亮 龚威 +1 位作者 陈隆勋 宋玉宽 《Acta meteorologica Sinica》 SCIE 1997年第3期307-319,共13页
In this paper,we present the results simulated with the Chinese regional climate model nested in NCAR CCM1 GCM through one-way nesting approach.The model has been run for 14 months. The NCAR CCM1(1992)is at rhomboidal... In this paper,we present the results simulated with the Chinese regional climate model nested in NCAR CCM1 GCM through one-way nesting approach.The model has been run for 14 months. The NCAR CCM1(1992)is at rhomboidal truncation(R15),while the horizontal resolution of the Chinese regional climate model is 100 km.It is found that the Chinese regional climate model has some advantages in simulating the surface air temperature and precipitation over the general climate model,because of the improved land surface parameterization. 展开更多
关键词 regional climate one way nesting simulation seasonal change
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