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Yang, H. X.; Li, J. Q.; Xiao, Ru; Shi, Youguo; Zhang, Huairuo

doi:10.1103/physrevb.72.075106

Cited by 8 publications

(9 citation statements)

References 33 publications

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“…Based on the Qamdo tree-ring δ 13 C, the Dasuopu ice core δ 18 O and previous composite temperature reconstruction for the Tibetan Plateau, together with other types of proxy data, [16] made an analysis of temperature change on the Tibetan Plateau during the last millennium. This work provides a basis for further integrated study of climate change.…”

Section: Climate Changes In Cryospheric Regions Of Chinamentioning

confidence: 99%

Global climate change and cryospheric evolution in China

Qin

Xiao

2009

Eur. Phys. J. Conferences

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Abstract. Major outcomes of Working Group I, IPCC AR4 (2007), as well as the recent understandings from our regional climatic assessments in China were summarized. Changes of cryosphere in China, one of the major components in regional climate system, is specifically reviewed. Under the global/regional warming, all components of cryosphere in China (Tibetan Plateau and surroundings) including glaciers, frozen ground (including permafrost) and snow cover show rapid decay in the last decades. These changes have big socioeconomic impacts in west China, thus encourages both government and scientists pay more and more attention to this field. Global climate change"Climate Change 2007: The Physical Science Basis", the Working Group I contribution to the IPCC Fourth Assessment Report (AR4) was launched [4]. IPCC assessment reports summarize peer-reviewed and comprehensive findings from international scientific communities, represent the current level of scientific understanding of global climate change research, and provide an important basis for international climate regime and relevant national policies. The report clearly indicates that the updated recent 100-year warming of the climate system is unequivocal, The most of the observed warming of the climate system over the last 50 years is very likely due to human activities. IPCC AR4 suggests the Arctic is very likely to warm during 21st century in most areas, and the annual mean warming is very likely to exceed the global mean warming. Warming is projected to be largest in winter and smallest in summer. It is likely that the Antarctic will be warmer and that precipitation will increase over the continent.IPCC AR4 gives the updated understanding of the relationship between past greenhouse gas concentrations and climate. (1) The combined radiative forcing from the three well-mixed greenhouse gases (CO 2 , CH 4 and N 2 O) is very likely unprecedented in at least the past 16 kyr. Pre-industrial variations of atmospheric greenhouse gas concentrations observed during the last 10 kyr were small compared to industrial era greenhouse gas increases. (2) It is very likely that the current atmospheric concentrations of CO 2 (379 ppm) and CH 4 (1,774 ppb) exceed by far the natural range of the last 650 kyr. Ice core data indicate that CO 2 varied within a range of 180 to 300 ppm and CH 4 within 320 to 790 ppb over this period. Over the same period, Antarctic temperature and CO 2 concentrations co-vary, indicating a close relationship between climate and the carbon cycle. (3) It is very likely that glacial-interglacial CO 2 variations have strongly amplified climate variations, but it is unlikely that CO 2 variations have triggered the end of a

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Section: Climate Changes In Cryospheric Regions Of Chinamentioning

confidence: 99%

Global climate change and cryospheric evolution in China

Qin

Xiao

2009

Eur. Phys. J. Conferences

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“…Systematical analysis suggests that noticeable spectral changes appear in both the low energy range (!10 eV) and the high-energy core losses along with water intercalation. We have listed the main observed peaks in range of 0-80 eV from all Na 0.33 CoO 2 $yH 2 O (yZ0, 0.6 and 1.3) samples in Table 1, and assigned the peaks based on the results of theoretical calculation [15]. It can be clearly recognized that the energy excitations below 10 eV change evidently with water intercalation.…”

Section: Resultsmentioning

confidence: 95%

“…Now we go on to discuss the local structure of the intercalated water layers in the Na x CoO 2 $yH 2 O superconducting hydrates. Recent theoretical and experimental investigations suggest that intercalated water layers during hydration have much complex structure rather than the simple ice-Ih state [14]; the water layers may not only just expand the crystal lattice and make the system more twodimensional in nature, but also tune the oxidation states of Co by existing as H 3 O C cluster [15]. IINS is a powerful tool for the structural characterization of hydrated inorganic compounds.…”

Section: Resultsmentioning

confidence: 99%

“…The discovery of superconductivity in water-intercalated Na 0.33 CoO 2 $yH 2 O immediately spurred a new round of intense interest in this system [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. A phase diagram of Na x CoO 2 for 0.3!x!0.75 has demonstrated the existence of two distinct metallic regions separated by an insulating state at xZ0.5 with the remarkable charge-ordering phenomenon [4].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Superconductivity, structural features and charge ordering in Na_xCoO₂·yH₂O (0≤y≤1.8) system

Yang

Shi

Xiao

et al. 2005

Science and Technology of Advanced Materials

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Structural and physical properties of Na x CoO 2 and superconducting Na x CoO 2 $yH 2 O hydrates have been systematically investigated. Raman scattering measurements reveal that the five active phonons in Na x CoO 2 $yH 2 O system change systematically with the H 2 O intercalation and modification of superconductivity, in particular the A 1g and E 1g modes in correlation with oxygen movements. Incoherent inelastic neutron scattering (IINS) study on the local structure of H 2 O-layers in Na x CoO 2 $yH 2 O (0%y%1.8) suggests the presence of three types of clusters, H 3 O C , H 5 O C and ice-Ih like weakly bonded water, among CoO 2 sheets. Electron energy loss (EEL) analysis on Na 0.33 CoO 2 $yH 2 O (0%y%1.3) indicates certain notable changes in the electronic structure during hydration. Microstructure and structural phase transitions accompanied with local atomic ordering in the charge-ordered phase Na 0.5 CoO 2 have been investigated along with the hexagonal-orthorhombic phase transition. q

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“…EELS is a powerful technique for measuring the valences of some transition metal elements [5,6]. In the EELS spectrum of transition metal, the intensities of L 3 and L 2 lines are related to the unoccupied states in the 3d bands [7], and a change in the valence state of cations introduced a dramatic change in L 3 /L 2 intensity ratio [8].…”

Section: Resultsmentioning

confidence: 99%