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Possible Evolutionary Models in the Initially Hydride Earth Theory
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作者 Kudryavtsev Pavel 《International Journal of Geosciences》 CAS 2023年第5期377-426,共50页
A modern view of the properties of chemical elements has confirmed the theory of the hot origin of the Earth. The next step in developing this theory was the hypothesis of the initial hydride Earth. In this work, we a... A modern view of the properties of chemical elements has confirmed the theory of the hot origin of the Earth. The next step in developing this theory was the hypothesis of the initial hydride Earth. In this work, we attempted to find additional evidence for this hypothesis and show additional effects that flow from it. The effect of the physical properties of atoms and ions on their behavior during the formation of the Earth was studied. The maximum contribution to the distribution of elements was made by those elements whose content in the original protoplanets of the disk was the maximum. Correlation dependence is obtained, which allows one to calculate the distribution of elements in the protoplanetary disk. It was shown that hydrogen was the main element in the proto substance located in the zone of the Earth’s formation. In this case, various chemical compounds formed, most represented by hydrogen compounds—hydrides. Since the pressure inside the Earth is 375 GPa, this factor forces the chemical compounds to adopt stoichiometry and structure that would not be available in atmospheric conditions. It is shown that many chemical elements at high pressure in a hydrogen medium form simple hydrides and super hydrides—polyhydrides with high hydrogen content. Pressure leads to a higher density of matter inside the planet. Given the possibility of forming polyhydrides, there is the possibility of binding the initially available hydrogen in an amount that can reach 49.3 mole%. Young Earth could contain about 10.7 mass% of hydrogen in hydrides, polyhydrides, and adsorbed form is almost twice higher than previous estimates. This fact additionally confirms the theory of the original hydride Earth. In hydrides, the occurrence of the phenomenon of superconductivity was discovered. Polyhydrides were shown as potential superconductors with a high critical temperature above 200 K. We, based on these data, hypothesized the presence of superconducting properties in the Earth’s core, which explains the presence of a magnetic field in the Earth, as well as the unevenness and instability of this field and the possibility of migration of the Earth’s poles. The fact that the Earth has a hydroid core causes its change in time due to the instability of hydrides. Arranged several possible models of the destruction of the Earth’s core. The calculations showed that both models give close results. These results give predictions that can be measured. The proposed models also made it possible to estimate the initial size of the Earth. Possible ways of further testing the hypothesis of the initial hydride Earth is shown. 展开更多
关键词 theory of the Hot Origin of the earth Magnetic Separation of Elements Atom Ionization Energy Hydrides Polyhydrides earth Expansion Superconductivity of the earth’s Core
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Comparative study of different theories on active earth pressure 被引量:1
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作者 S.P.Yap F.A.Salman S.M.Shirazi 《Journal of Central South University》 SCIE EI CAS 2012年第10期2933-2939,共7页
Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs.A number of analytical theories on active earth pressure were presented.Yet,there are limited studies on compar... Determination of distribution and magnitude of active earth pressure is crucial in retaining wall designs.A number of analytical theories on active earth pressure were presented.Yet,there are limited studies on comparison between the theories.In this work,comparison between the theories with finite element analysis is done using the PLAXIS software.The comparative results show that in terms of distribution and magnitude of active earth pressure,RANKINE's theory possesses the highest match to the PLAXIS analysis.Parametric studies were also done to study the responses of active earth pressure distribution to varying parameters.Increasing soil friction angle and wall friction causes decrease in active earth pressure.In contrast,active earth pressure increases with increasing soil unit weight and height of wall.RANKINE's theory has the highest compatibility to finite element analysis among all theories,and utilization of this theory leads to proficient retaining wall design. 展开更多
关键词 主动土压力 挡土墙设计 有限元分析 内摩擦角 土压力分布 分析理论 朗肯理论 RANK
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Earth Ecosystem Theory: IV Theory Application
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作者 Yang Dongfang Wang Fengyou +2 位作者 Zhu Sixi Wu Youfu He Huazhong 《Meteorological and Environmental Research》 CAS 2014年第12期4-8,共5页
By the application of earth ecosystem theory, three complementary mechanisms of earth ecosystem and ecological power of North Pacific are elaborated fully. Aided by three ecological sub-systems of earth ecosystem: te... By the application of earth ecosystem theory, three complementary mechanisms of earth ecosystem and ecological power of North Pacific are elaborated fully. Aided by three ecological sub-systems of earth ecosystem: terrestrial ecosystem, marine ecosystem and atmospheric ecosystem, running track of Si is showed. Under the theoretical guidance of three complementary mechanisms of earth ecosystem, we predict future climate mode of the earth, and climate in 2010 gave confirm. Therefore, the theoretical system of earth ecosystem is conductive to studying global issues, including change processes and tendencies of resource, ecology, environment and disaster. Then, it is beneficial to human healthy survival and sustainable development of the earth ecosystem. 展开更多
关键词 earth ecosystem theory APPLICATION China
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Self-regulation and Emotional Resilience in the Workplace.A Systematic Review
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作者 Michael Sotiriadis Michael Galanakis 《Psychology Research》 2022年第12期957-964,共8页
The current project provides a systemic literature review on the self-regulation theory analyzing the history,the main concepts,and an integrated model of analyzing the theory.Following,emotional resilience is describ... The current project provides a systemic literature review on the self-regulation theory analyzing the history,the main concepts,and an integrated model of analyzing the theory.Following,emotional resilience is described and linked with the self-regulation theory proving their connection,through emotional regulation.The literature review provides tangible resources for individuals to understand and apply in everyday life tactics that will assist them in fostering greater emotional resilience in the workplace,utilizing the self-regulation theory.Finally,a brief discussion is provided in terms of how to evaluate critically the concepts mentioned while limitations and future research are also indicated.This paper aims to invite conversation and collaboration in discovering a relatively new field that could in the future reimagine the workplace. 展开更多
关键词 self-regulation theory emotional resilience emotional regulation emotionally resilient workplace organizational psychology
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Magnetic Isotope Theory of the Origin of Life on Earth
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作者 Aibassov Yerkin Nakisbekov Narymzhan +1 位作者 Yemelyanova Valentina Savizky Ruben 《Journal of Chemistry and Chemical Engineering》 2016年第6期301-304,共4页
关键词 地球生命起源 放射性同位素 有机化合物 电磁辐射
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霍夫斯泰德文化维度理论下的中美差异探究——以《流浪地球2》和《星际穿越》为例
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作者 王乐 《语言与文化研究》 2024年第1期187-190,共4页
电影作为人类文化生活中重要的精神产物,必定会受到创作者世界观、人生观、价值观的影响,进而展现其背后的民族与文化差异。长期以来,科幻题材因情节独特、创作难度大、人文情怀丰富而备受关注。本文以霍夫斯泰德文化维度理论为理论框架... 电影作为人类文化生活中重要的精神产物,必定会受到创作者世界观、人生观、价值观的影响,进而展现其背后的民族与文化差异。长期以来,科幻题材因情节独特、创作难度大、人文情怀丰富而备受关注。本文以霍夫斯泰德文化维度理论为理论框架,提取电影《流浪地球2》及《星际穿越》中的经典话语与文化现象,探究中美科幻电影中的文化差异及其深层原因,以期促进大众对不同文化的客观认识,并对文化电影的制作有所启发。 展开更多
关键词 霍夫斯泰德文化维度理论 《流浪地球2》 《星际穿越》 中美文化差异
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Study on the interannual variability of the Kerama Gap transport and its relation to the Kuroshio/Ryukyu Current system
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作者 Han Zhou Kai Yu +3 位作者 Jianhuang Qin Xuhua Cheng Meixiang Chen Changming Dong 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期1-14,共14页
An analysis of a 68-year monthly hindcast output from an eddy-resolving ocean general circulation model reveals the relationship between the interannual variability of the Kerama Gap transport(KGT)and the Kuroshio/Ryu... An analysis of a 68-year monthly hindcast output from an eddy-resolving ocean general circulation model reveals the relationship between the interannual variability of the Kerama Gap transport(KGT)and the Kuroshio/Ryukyu Current system.The study found a significant difference in the interannual variability of the upstream and downstream transports of the East China Sea-(ECS-)Kuroshio and the Ryukyu Current.The interannual variability of the KGT was found to be of paramount importance in causing the differences between the upstream and downstream ECS-Kuroshio.Additionally,it contributed approximately 37%to the variability of the Ryukyu Current.The interannual variability of the KGT was well described by a two-layer rotating hydraulic theory.It was dominated by its subsurface-intensified flow core,and the upper layer transport made a weaker negative contribution to the total KGT.The subsurface flow core was found to be mainly driven by the subsurface pressure head across the Kerama Gap,and the pressure head was further dominated by the subsurface density anomalies on the Pacific side.These density anomalies could be traced back to the eastern open ocean,and their propagation speed was estimated to be about 7.4 km/d,which is consistent with the speed of the local first-order baroclinic Rossby wave.When the negative(positive)density anomaly signal reached the southern region of the Kerama Gap,it triggered the increase(decrease)of the KGT towards the Pacific side and the formation of an anticyclonic(cyclonic)vortex by baroclinic adjustment.Meanwhile,there is an increase(decrease)in the upstream transport of the entire Kuroshio/Ryukyu Current system and an offshore flow that decreases(increases)the downstream Ryukyu Current. 展开更多
关键词 Kerama Gap KUROSHIO Ryukyu Current OGCM for the earth Simulator(OFES) hydraulic theory
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碱土金属离子Ca^(2+)和Mg^(2+)催化木质素二聚体热解过程的机理研究
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作者 蒋晓燕 李一鸣 +3 位作者 汤溧 杜晓娇 代兰花 胡斌 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第7期959-966,共8页
本研究采用密度泛函理论方法,对碱土金属离子(Ca^(2+)、Mg^(2+))作用下的β-O-4型木质素二聚体模型化合物(2-[2-(4-甲氧基苯基)乙氧基]-苯甲醚,mc)的热解反应路径进行了理论计算。计算结果表明,Ca^(2+)和Mg^(2+)会与木质素二聚体模型化... 本研究采用密度泛函理论方法,对碱土金属离子(Ca^(2+)、Mg^(2+))作用下的β-O-4型木质素二聚体模型化合物(2-[2-(4-甲氧基苯基)乙氧基]-苯甲醚,mc)的热解反应路径进行了理论计算。计算结果表明,Ca^(2+)和Mg^(2+)会与木质素二聚体模型化合物mc的Cβ位氧原子及甲氧基上的氧原子结合形成稳定的复合物,从而影响C_(α)−C_(β)和Cβ−O的键长和热解反应能垒。在热解过程中,Ca^(2+)和Mg^(2+)会促进协同断裂反应的发生,从而促进产物1-甲氧基-4-乙烯基苯、2-甲氧基苯酚和邻苯二酚的生成;抑制C_(α)−C_(β)键和Cβ−O键的均裂反应,从而抑制产物1-乙基-4-甲氧基苯、2-羟基苯甲醛的生成。 展开更多
关键词 碱土金属离子 木质素二聚体 β-O-4连接 热解机理 密度泛函理论
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基于谷歌地球引擎和分形理论的黄河三角洲土地利用空间结构研究
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作者 马东岭 刘卫星 张春红 《土壤》 CAS CSCD 北大核心 2024年第3期655-665,共11页
基于谷歌地球引擎(Google earth engine,GEE),以Landsat-5(TM)、Landsat-7(ETM)和Landsat-8(OLI)数据为遥感数据源,采用随机森林分类方法对黄河三角洲生态功能保护区1985—2020年的土地利用类型进行了划分,在此基础上利用分形理论方法... 基于谷歌地球引擎(Google earth engine,GEE),以Landsat-5(TM)、Landsat-7(ETM)和Landsat-8(OLI)数据为遥感数据源,采用随机森林分类方法对黄河三角洲生态功能保护区1985—2020年的土地利用类型进行了划分,在此基础上利用分形理论方法计算了土地利用分形维数和稳定性指数,并分两个阶段对研究区土地利用空间结构的复杂度和稳定性进行了定量分析。结果表明:①1985—2020年,研究区的耕地面积逐渐减少;草地面积相对较稳定;水体面积逐渐扩大,2015—2020年增长率最高;裸地面积的变化较为波动,先增加后又逐渐下降;建筑物面积呈指数增长。②研究区土地利用空间结构的分形维数总体上呈降低趋势,表明土地利用复杂度降低。③研究区土地利用空间结构的稳定性指数总体上呈升高趋势,表明土地利用空间结构趋向稳定。总体上,黄河三角洲生态功能保护区随着环境保护政策的实施,土地利用空间结构逐渐得到改善,水、草等自然资源逐渐丰富。 展开更多
关键词 谷歌地球引擎 分形理论 空间结构 时空变化 黄河三角洲
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硫醚与2-甲基-1,5-己二烯反应的机理研究
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作者 李青益 石云 +7 位作者 刘国魁 冷霞 李云志 韦瑶瑶 王佳祺 周慧敏 周广丽 夏其英 《原子与分子物理学报》 北大核心 2024年第3期41-44,共4页
采用密度泛函理论对硫醚与2-甲基-1,5-己二烯的反应机理进行了详细的理论探究.计算结果表明,该反应历程主要包含活性物种的生成、2-甲基-1,5-己二烯的插入、另一分子的硫醚的碳氢键活化三部分.在2-甲基-1,5-己二烯插入步骤中,发现其采用... 采用密度泛函理论对硫醚与2-甲基-1,5-己二烯的反应机理进行了详细的理论探究.计算结果表明,该反应历程主要包含活性物种的生成、2-甲基-1,5-己二烯的插入、另一分子的硫醚的碳氢键活化三部分.在2-甲基-1,5-己二烯插入步骤中,发现其采用6-5-re-插入时需要克服的活化能垒最低,反应时更为占优,在进行烯烃分子内碳碳双键插入完成闭环反应时相对比较容易.通过能量对比探明硫醚的C-H键活化需要克服的能垒最高,为该反应的速控步. 展开更多
关键词 稀土金属配合物 碳氢键活化 密度泛函理论
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国土空间规划的基础性理论问题
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作者 董祚继 程雅淇 +1 位作者 孟海燕 王赛红 《中国土地科学》 CSCD 北大核心 2024年第1期27-35,共9页
研究目的:从规划理论构成入手,讨论国土空间的系统科学理论、动态平衡原理、演化组织机制等基础性理论问题,为规划实践提供指导。研究方法:文献研究法。研究结果:(1)国土空间规划的理论构成远远超出传统的建筑学范畴,大量融入地理学、... 研究目的:从规划理论构成入手,讨论国土空间的系统科学理论、动态平衡原理、演化组织机制等基础性理论问题,为规划实践提供指导。研究方法:文献研究法。研究结果:(1)国土空间规划的理论构成远远超出传统的建筑学范畴,大量融入地理学、生态学、海洋学、信息学、经济学、管理学、民法学、景观学等学科知识。(2)国土空间规划的对象是“地理综合体”,规划理论主要来源于不同尺度“地理综合体”的系统科学原理,包括地球表层系统科学理论、人地关系地域系统理论、土地系统科学理论、景观生态学理论、人居环境科学理论等。(3)国土空间规划本质上是通过对国土空间系统要素的调控,保证系统物质循环和能量转换的畅通即动态平衡,包括自然系统的动态平衡、经济系统的动态平衡、社会系统的动态平衡和国土空间系统的综合动态平衡。(4)国土空间系统的演化发展是自组织机制与他组织机制共同作用的结果,自组织机制包括规模演化机制、结构演化机制和格局演化机制,他组织机制主要包括空间规划、用途管制、民主监督和信息监管等。研究结论:国土空间规划作为生态文明体制改革的产物和新时代国家空间治理的重要工具,是一个涉及多学科的庞大知识体系,亟待推进理论创新及其基础上的制度创新。 展开更多
关键词 国土空间规划 规划理论 地球表层系统科学 动态平衡 自组织机制
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一元而非二元的理学“性”论--论“气质之性”非“气质的性”
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作者 毕明良 《山东青年政治学院学报》 2024年第3期1-10,共10页
理学的“性”是本体化的概念,其“性”论解释了人与物、人与人、物与物的种种差别,不是狭义的人性论,而是其本体论之一部分。“气质之性”不是指气质本身的“性”,而是指本体意义的“天地之性”透过人物所禀的具体气质而在经验世界呈现... 理学的“性”是本体化的概念,其“性”论解释了人与物、人与人、物与物的种种差别,不是狭义的人性论,而是其本体论之一部分。“气质之性”不是指气质本身的“性”,而是指本体意义的“天地之性”透过人物所禀的具体气质而在经验世界呈现出来的具体状态,“天地之性”与“气质之性”是体用关系,而非并列的二元关系。 展开更多
关键词 理学 气质之性 天地之性 性论
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Band gap calculation and photo catalytic activity of rare earths doped rutile TiO_2 被引量:13
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作者 边亮 宋绵新 +2 位作者 周天亮 赵效勇 戴清清 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第3期461-468,共8页
The density of states (DOS) of 17 kinds of rare earths (RE) doped rutile TiO2 was by using first-principles density functional theory (DFT) calculation. The band gap widths of RE doped futile TiO2 were important... The density of states (DOS) of 17 kinds of rare earths (RE) doped rutile TiO2 was by using first-principles density functional theory (DFT) calculation. The band gap widths of RE doped futile TiO2 were important factors for altering their absorbing wavelengths. The results show that RE ions could obviously reduce the band gap widths and form of energy of ruffle TiO2 except Lu, Y, Yb and Sc, and the order of absorbing wavelengths of RE doped ruffle TiO2 were the same as that of the results of calculation. The ratio of RE dopant was another important factor for the photo catalytic 'activity of RE doped rutile TiO2, and there was an optimal ratio of dopant. There was a constant for predigesting the calculation difficulty, respectively, which were 0.5mol.% and 100 mol^-1 under supposition. The band gap widths of RE doped rutile TiOz by DFT calculation were much larger than that by experiment. Finally, by transferring the calculation values to experiment values, it could be found and predicted that RE enlarged obviously the absorbing wavelengh of ruffle TiO2. In addition, the degree of RE ions edging out the Ti atom using the parameters of RE dements was computed. 展开更多
关键词 density functional theory ruffle TiO2 band gap rare earths
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Effects of Earth's curvature and radial heterogeneity in dislocation studies:Case studies of the 2008 Wenchuan earthquake and the 2004 Sumatra earthquake 被引量:4
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作者 Guangyu Fu Wenke Sun +2 位作者 Yoichi Fukuda Shanghua Gao Takashi Hasegawa 《Earthquake Science》 CSCD 2010年第4期301-308,共8页
Recently, effects of Earth's curvature and radial heterogeneity on coseismic deformations are often investi- gated based on the 2004 Sumatra earthquake. However, such effects are strongly related to earthquake types.... Recently, effects of Earth's curvature and radial heterogeneity on coseismic deformations are often investi- gated based on the 2004 Sumatra earthquake. However, such effects are strongly related to earthquake types. As a low dip angle event, the 2004 Sumatra earthquake is not a good seismic case for such a topic since the effects for moderate dip angle events are much bigger. In this study, the half-space and spherical dislocation theories are used, respectively, to calculate co- seismic displacements caused by the 2008 Wenchuan earthquake and the 2004 Sumatra earthquake. Effects of Earth's curva- ture and stratification are investigated through the discrepancies of results calculated using the two dislocation theories. Re- sults show that the effects of Earth's curvature and stratification for the 2008 Wenchuan earthquake are much larger than those for the 2004 Sumatra earthquake. Ignoring the effects will cause errors up to 100%-200% in far field displacements for a moderate dip angle event like the 2008 Wenchuan earthquake. Such great effects are much bigger than those conclusions of previous studies. Besides, comparison with observations verifies that spherical dislocation theories yield better results than half-space ones in far fields. 展开更多
关键词 coseismic displacement dislocation theory earth model
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Fluorescence and Judd-Ofelt analysis of rare earth complexes with maleic anhydride and acrylic acid 被引量:3
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作者 温世鹏 张小萍 +2 位作者 胡水 张立群 刘力 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第6期787-791,共5页
Two kinds of Eu-complexes, Eu(TTA)2(Phen)(AA) and Eu(TTA)2(Phen)(MA) (HTTA=2-Thenoyltrifluoroacetone, Phen=1,10- phenanthroline, AA=acrylic acid, MA=Maleic anhydride), which combined the excellent fluore... Two kinds of Eu-complexes, Eu(TTA)2(Phen)(AA) and Eu(TTA)2(Phen)(MA) (HTTA=2-Thenoyltrifluoroacetone, Phen=1,10- phenanthroline, AA=acrylic acid, MA=Maleic anhydride), which combined the excellent fluorescence properties of Eu(TTA)2(Phen)(H2O) and the reactivity of acrylic acid and maleic anhydride with radicals, were synthesized. The two complexes were characterized by elemental analysis, infrared (IR) spectra, and X-ray photoelectron spectroscopy (XPS). Based on the data shown from the fluorescent spectra of the Eu-MA and Eu-AA complexes, the Ωλ (λ=2 and 4) experimental intensity parameters were calculated. The results demonstrated that the Ω2 intensity parameters for the two complexes were smaller than those for the Eu(TTA)2(Phen)(H2O) complex, indicating that a less symmetrical chemical environment existed in the complexes. It implied that the radiative efficiency of the ^5D0 of these two complexes could be enhanced by ligand of MA and AA, respectively. The luminescent lifetime of the Eu-AA (r=-7.26×10^-4 s) or Eu-MA complex (r=-8.12×10^-4 s) was higher than that of the Eu(TTA)2(Phen)(H2O) complex, which was attributed to the substitution of the water molecule (H2O) in Eu(TTA)2(Phen)(H2O) by the MA or AA ligand. 展开更多
关键词 organic ligands XPS spectra Judd-Ofelt theory rare earths
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Spectroscopic Properties and Judd-Ofelt Theory Analysis of Er^(3+)-Doped Heavy Metal Oxyfluoride Silicate Glass 被引量:3
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作者 徐时清 杨中民 +3 位作者 戴世勋 张军杰 胡丽丽 姜中宏 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第3期375-380,共6页
Er^(3+)-doped heavy metal oxyfluoride silicate glass was fabricated and characterized, and the absorption spectrum and fluorescence spectrum of the glass were studied. The Judd-Ofelt intensity parameters Ω_t (t =2, ... Er^(3+)-doped heavy metal oxyfluoride silicate glass was fabricated and characterized, and the absorption spectrum and fluorescence spectrum of the glass were studied. The Judd-Ofelt intensity parameters Ω_t (t =2, 4, 6), spontaneous transition probability, fluorescence branching ratio and radiative lifetime of each energy levels for Er^(3+) were calculated by Judd-Ofelt theory, and stimulated emission cross-section of (()~4I_(13/2))→(()~4I_(15/2)) transition was calculated by McCumber theory. The results show that fluorescence full width at half maximum and stimulated emission cross-section of Er^(3+)-doped heavy metal oxyfluoride silicate glass are broad and large, respectively. Compared with other host glasses, the gain bandwidth property of Er^(3+)-doped heavy metal oxyfluoride silicate glass is close to those of tellurite and bismuth glasses, and has advantage over those of silicate, phosphate and germante glasses. 展开更多
关键词 inorganic nonmetallic materials heavy metal oxyfluoride silicate glass Er^(3+) ion spectroscopic properties Judd-Ofelt theory rare earths
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Multisphere Tectonics of the Earth System 被引量:1
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作者 REN Jishun NIU Baogui +5 位作者 XU Qinqin ZHAO Lei LIU Jianhui LI Shan ZHU Junbin LIU Renyan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第3期727-741,共15页
The fundamental theoretical framework of the Multisphere Tectonics of the Earth System is as follows:(1)It intends to extend the geotectonic studies from the crustal and lithospheric tectonics to the multisphere tecto... The fundamental theoretical framework of the Multisphere Tectonics of the Earth System is as follows:(1)It intends to extend the geotectonic studies from the crustal and lithospheric tectonics to the multisphere tectonics of the Ear th system as a whole.(2)The global dynamics driven by both the Earth system and the cosmic celestial system:solar energy,multispheric interactions of the Earth system and the combined effects of the motions of celestial bodies in the cosmos syste m are the driving forces of various geological processes.(3)The Continent-Ocean transformation theory:the continent and ocean are two opposite yet unified geological units,which can be transformed into each other;neither continent nor ocean wi ll survive forever;there is no one-way development of continental accretion or ocean extinction;the simple theory of one-way continental accretion is regarded as invalid.(4)The continental crust and mantle are characterized by multiple layers,with different layers liable to slide along the interfaces between them,but corroboration is needed that continents move as a who le or even drift freely.(5)The cyclic evolution theory:the development of Earth’s tectonics is not a uniform change,but a spiral forward evolution,characterized by a combination of non-uniform,non-linear,gradual and catastrophic changes;different evolutionary stages(tectonic cycles)of Earth have distinctive global tectonic patterns and characteristics,one tectonic mo del should not be applied to different tectonic cycles or evolutionary stages.(6)The structure and evolution of Earth are asymmetric and heterogeneous,thus one tectonic model cannot be applied to different areas of the world.(7)The polycyclic evolution of the continental crust:the continental crust is formed by polycyclic tectonics and magmatism,rather than simply lateral or vertical accretion.(8)The role of deep faults:the deep fault zones cutting through different layers of the crus t a nd mantle usually play important roles in tectonic evolution.For example,the present-day mid-ocean ridge fault zones,transform fault zones and Benioff zones outline the global tectonic framework.Different tectonic cycles and stages of Earth’s evolutio n must have their own distinctive deep fault systems which control the global tectonic framework and evolutionary processes during different tectonic cycles and stages.Starting from the two mantle superplumes Jason(Pacific)and Tuzo(Africa),the study of the evolutionary process of the composition and structure of the crust and mantle during the great transformation an d reorganization of the Meso-Cenozoic tectonic framework in China and the other regions of Asia is a good demonstration of theory of Multisphere Tectonics of the Earth System. 展开更多
关键词 deep fault global dynamics cyclic evolution theory Multisphere Tectonics Continent-Ocean transformation theory earth system science
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Density Functional Theory Study on La Complex with Schiff-base as Building Block 被引量:6
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作者 XIA Shu-Wei XU Xiang SUN Ya-Li FAN Yu-Hua BI Cai-Feng ZHANG Dong-Mei YANG Li-Rong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第2期197-203,共7页
Quantum density functional theory (DFT) results are reported for the building block [LaL^1(NO3)] of La complex [LaL^1(NO3)]NO3·5H2O (L^1 = (CH3)2CHCH2CH(NCHC4H3O)COO^-). The structure was optimized an... Quantum density functional theory (DFT) results are reported for the building block [LaL^1(NO3)] of La complex [LaL^1(NO3)]NO3·5H2O (L^1 = (CH3)2CHCH2CH(NCHC4H3O)COO^-). The structure was optimized and the calculation results show that the lanthanum ion is coordinated by one nitrogen atom and three oxygen atoms of L^1 and two oxygen atoms of nitrate ion. The bond length of La-N is 0.2637 nm and the average length of La-O is 0.2526 nm, which are consistent with the literatures. In addition, the stabilities, electronic structural characteristics and IR spectra of the complex have been analyzed, which describe the coordination of lanthanum ion with other atoms in detail. 展开更多
关键词 RARE-earth SCHIFF-BASE lanthanum complex density functional theory
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Effects of the Earth’s triaxiality on the polar motion excitations 被引量:2
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作者 Chen Wei Shen Wenbin 《Geodesy and Geodynamics》 2012年第2期1-7,共7页
This study aims to evaluate the significance of the Earth' s triaxiality to the polar motion theory. First of all, we compare the polar motion theories for both the triaxial and rotationally-symmetric Earth models, w... This study aims to evaluate the significance of the Earth' s triaxiality to the polar motion theory. First of all, we compare the polar motion theories for both the triaxial and rotationally-symmetric Earth models, which is established on the basis of the EGM2008 global gravity model and the MHB2000 Earth model. Then, we use the atmospheric and oceanic data (the NCEP/NCAR reanalyses and the ECCO assimulation products) to quantify the triaxiality effect on polar motion excitations. Numerical results imply that triaxiality only cause a small correction ( about 0. 1 - 0. 2 mas) to the geophysical excitations for the rotationally-symmetric case. The triaxiality correction is much smaller than the errors in the atmospheric and oceanic data, and thus can be neglected for recent studies on polar motion excitations. 展开更多
关键词 earth rotation theory dynamic figure parameter atmospheric-oceanic excitation
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Co-seismic Coulomb stress changes on the northern Tanlu fault zone caused by the Tohoku-Oki M_(W)9.0 earthquake 被引量:1
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作者 Fei Chen Tai Liu +2 位作者 Yawen She Xing Huang Guangyu Fu 《Earthquake Science》 2020年第1期11-22,共12页
Based on the spherical earth dislocation theory and a fault slip model of the Tohoku-Oki M_(W)9.0 earthquake,the co-seismic Coulomb failure stress changes(ΔCFS)on the northern Tanlu fault zone at depths of 0–40 km a... Based on the spherical earth dislocation theory and a fault slip model of the Tohoku-Oki M_(W)9.0 earthquake,the co-seismic Coulomb failure stress changes(ΔCFS)on the northern Tanlu fault zone at depths of 0–40 km are calculated.By comparing two sets of results from the spherical earth dislocation theory and the semi-infinite space one,the effect of earth curvature on the calculation results is analyzed quantitatively.First,we systematically summarize previous researches related to the northern Tanlu fault zone,divide the fault zone as detailed as possible,give the geometric parameters of each segment,and establish a segmented structural model of the northern Tanlu fault zone.Second,we calculate the Coulomb stress changes on the northern Tanlu fault zone by using the spherical earth dislocation theory.The result shows the Coulomb stress changes are no more than 0.003 MPa,which proves the great earthquake did not significantly change the stress state of the fault zone.Finally,we quantitatively analyze the disparities between the results of semi-infinite space dislocation theory and the spherical earth one.The average disparity between them is about 7.7%on the northern Tanlu fault zone and is 16.8%on the Fangzheng graben,the maximum disparity on this graben reaches up to 25.5%.It indicates that the effect of earth curvature can not be ignored.So it’s necessary to use the spherical earth dislocation theory instead of the semi-infinite space one to study the Coulomb stress change in the far field. 展开更多
关键词 the northern Tanlu fault zone segmented structural model spherical earth dislocation theory the Tohoku-Oki M_(W)9.0 earthquake co-seismic Coulomb stress change(△CFS)
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