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Quantitative Expression of Heat Flow versus Tectonic Deformation in the China Continent: The Effects of Plastic-Flow Network and Stable Block 被引量:1
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作者 WANG Sheng-zu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第1期97-109,共13页
Based on the heat flow data published in 1990 and 2001, a study of the factors influencing the terrestrial heat flow distribution in the China continent and its quantitative expression is carried out using the "Netli... Based on the heat flow data published in 1990 and 2001, a study of the factors influencing the terrestrial heat flow distribution in the China continent and its quantitative expression is carried out using the "Netlike Plastic-Flow" continental dynamics model and the methods of statistic analysis and optimum fitting. The result indicates that the factors influencing the heat flow distribution is classified into two groups, i.e. background and tectonic ones, in which the former mainly involves the non- uniform distribution of mantle heat flow, heat production of radioactive dements in the crust, heattransfer media and hydrothermal circulation, while the latter mainly involves plastic-flow networks and relatively-stable blocks. The plastic-flow network is a manifestation of shear localization in the netlike plastic-flow process in the lower lithosphere, which is composed of two sets of plastic-flow belts (PFBs) intersecting each other and, as one of the basic action regimes, controls the intraplate tectonic deformation. Relatively stable blocks (RSBs), which are the tectonic units with relatively-high viscosities existing in the netlike plastic-flow field, as one of the principal origins, result in the development of large-seale compressional basins. PFB and RSB, as the active and quiet states of tectonic deformation, give rise to the higher and lower heat flow values, respectivdy. The provincial average heat flow in continent can be estimated using the expression qav = q0 + a Pbt-c Pbk, where the three terms of the right side are background heat flow, PFB-positive contribution and RSB-negative contribution, Pbt and Pbk are the PFB- and RSB-coverage ratios, respectively, a is the coefficient of PFB- positive contribution depending mainly on the strain in the lower lithosphere, and c is the coefficient of RSB-negative contribution related mainly to the thickness of the lithosphere, the aseismic-area ratio and the tectonic age. For the major portion of the China continent excluding some of the southeastern region of China, the confidence interval of the provincial average background heat flow is qo=57.25±24.8 mW/m^2 and the PFB-positive- and RSB-negative-contribution coefficients are a=14.8-71.9 mW/m^2 and c=0-25.6 mW/m^2, respectively. The concepts of PFB and RSB effects and the heat flow expression suggested provide a new choice of the approach to the quantitative description of the characteristics of heat flow distribution in continent and their physical mechanisms. 展开更多
关键词 continental lithosphere terrestrial heat flow plastic-flow network relatively stable block heat-flow expression
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Structural Characters and Isolated Stability of Phosphorus Polyanions
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作者 LIPing 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第4期467-477,共11页
The optimized geometries at the RHF/6-311++G** level, the relatively stable energy at the MPW1PW91/6-311++G** level and the structural characters of anions have been acquired, indicating the stability is related to ... The optimized geometries at the RHF/6-311++G** level, the relatively stable energy at the MPW1PW91/6-311++G** level and the structural characters of anions have been acquired, indicating the stability is related to the chemical bonding of μ2?P atoms and the distri- bution of negative charges. The configurations of cage units P8 4- and P9 5- are stable due to the less torsion, but their ES values are relatively higher than that of P7 3- with more μ2?P atoms and the isolated stability is lower than that of P7 . They potentially play an important role as intermediate 3- in chemical reaction of producing complicated polyphosphides. Based on the related electronic properties, a stable polyanion must have low valence electron concentration, no (μ2?P)?(μ2?P) bond and a little dispersive charge. The earmark IR frequencies of cage units have been assigned to the vibration models in the end. 展开更多
关键词 phosphorus polyanions P8 ~P26 stereo configuration cage units 4- 4- relatively stable energy vibration frequencies STABILITY
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