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1.
Larisa Fleishman 《Geoforum》2008,39(2):1021-1043
The Green Line constituted the armistice line between Israel and Jordan during the period 1949-1967. This paper discusses the familiarity of Israeli students with the nature and geographical location of the Green Line by restructuring and analyzing their mental maps. The findings of this study show that students who are men, long-term residents, identify themselves on the left end of the political spectrum, and professional geographers, show better knowledge concerning the issue of borders. However, most students revealed a certain vagueness and even ignorance concerning both spatial perception of the Green Line and its essence. The reasons for the revealed phenomenon are also discussed in this paper, as well as the behavioral implications of the familiarity with the Green Line, both in spatial and political contexts. 相似文献
2.
With rising public awareness of climate change, celebrities have become an increasingly important community of non nation-state ‘actors’ influencing discourse and action, thereby comprising an emergent climate science-policy-celebrity complex. Some feel that these amplified and prominent voices contribute to greater public understanding of climate change science, as well as potentially catalyze climate policy cooperation. However, critics posit that increased involvement from the entertainment industry has not served to influence substantive long-term advancements in these arenas; rather, it has instead reduced the politics of climate change to the domain of fashion and fad, devoid of political and public saliency. Through tracking media coverage in Australia, Canada, the United States, and United Kingdom, we map out the terrain of a ‘Politicized Celebrity System’ in attempts to cut through dualistic characterizations of celebrity involvement in politics. We develop a classification system of the various types of climate change celebrity activities, and situate movements in contemporary consumer- and spectacle-driven carbon-based society. Through these analyses, we place dynamic and contested interactions in a spatially and temporally-sensitive ‘Cultural Circuits of Climate Change Celebrities’ model. In so doing, first we explore how these newly ‘authorized’ speakers and ‘experts’ might open up spaces in the public sphere and the science/policy nexus through ‘celebritization’ effects. Second, we examine how the celebrity as the ‘heroic individual’ seeking ‘conspicuous redemption’ may focus climate change actions through individualist frames. Overall, this paper explores potential promises, pitfalls and contradictions of this increasingly entrenched set of ‘agents’ in the cultural politics of climate change. Thus, as a form of climate change action, we consider whether it is more effective to ‘plant’ celebrities instead of trees. 相似文献
3.
Studying spatial and temporal variation of soil loss is of great importance because of global environmental concerns. Understanding
the spatial distribution of soil erosion and deposition in the high-cold steppe is important for designing soil and water
conservation measures. Measured 137Cs losses (Bq m−2) from long-term high altitude (4,000 m above sea level) watershed plots on the Qinghai–Tibet plateau and derived soil erosion
estimates (Mg ha−1 year−1) were significantly correlated to directly measured soil losses from the same plots, over the same period (1963–2005). The
local reference inventory was estimated to be 2,468 Bq m−2. The result of analyzing 137Cs distribution and its intensity in the soil profiles in this area shows similarities to 137Cs distribution in other areas. 137Cs is basically distributed in the topsoil layer of 0–0.3 m. Soil erosions vary greatly in the entire sampled area, ranging
from 5.5 to 23 Mg ha−1 year−1, with an average of 16.5 Mg ha−1 year−1 which is a moderate rate of erosion. 相似文献
4.
V. M. Ryzhkov V. N. Anfilogov I. A. Blinov A. A. Krasnobaev P. M. Valizer 《Doklady Earth Sciences》2016,469(2):824-827
The results of study of phase equilibria in the MgO–SiO2–ZrO2 system at 1450–1550°C are reported. The studied system contains two eutectic points and six fields: (I) MgSiO3 + SiO2; (II) MgSiO3 + ZrO2; (III) ZrSiO4 + SiO2; (IV) MgSiO3 + Mg2SiO4; (V) ZrO2 + MgO; (VI) ZrSiO4 + ZrO2. The presence of fields (II) and (III) on the diagram shows that zircon in equilibrium with olivine and pyroxene crystallizes at very low concentrations of ZrO2 in the system. This provides a solution for one of the most important problems in zirconology of dunites: the probability of the formation and preservation of zircon in the course of the formation and evolution of dunite. 相似文献
5.
J. N. Hindayar P. Dasarwar S. P. Srivastava N. Thrideep Kumar Murali Mohan S. K. Som 《Journal of the Geological Society of India》2016,88(2):197-205
Understanding the causes of slope development with movement initiation of land sliding requires knowledge on dynamicity, displacement, strain concentration and factor of safety. The 13th mile landslide on Gangtok-Nathula road of the Sikkim Himalaya has seriously affected the Indo-China trade route. To quantify the spatial movement pattern, strain analysis and identification of zones of safety were attempted which indicates that differential movement activity of the landslide zone is co-relatable with differential strain pattern with an overall imprint of the Himalaya collision tectonics. 相似文献
6.
Ling-Ling Xiao Chun-Ming Wu Guo-Chun Zhao Jing-Hui Guo Liu-Dong Ren 《International Journal of Earth Sciences》2011,100(4):717-739
Garnet-bearing metapelites and amphibolites are exposed in the south and middle parts of the Zanhuang complex, which is located
in the central segment of the nearly NS-striking Trans-North China Orogen. These rocks preserve three metamorphic mineral
assemblages forming at the prograde, peak and post-peak decompression stages. The prograde metamorphic stage (M1) is represented by mineral inclusions within garnet porphyroblasts, the peak metamorphic stage (M2) is represented by garnet rims and matrix minerals, whereas the retrograde stage (M3) is represented by amphibole + plagioclase symplectite rimming garnet porphyroblasts in the amphibolites and biotite + plagioclase
symplectite rimming garnet porphyroblasts in the metapelites. All garnet porphyroblasts in the metapelites preserve prograde
chemical zoning except for the ubiquitous, quite narrow zones from the underwent post-peak decompression. It has been determined
through thermobarometric computation that the metamorphic conditions are 650–710°C at 8.2−9.2 kbar for the M1 (inclusion) assemblages, >810°C at >12.5 kbar for the metamorphic peak M2 (matrix) assemblages, and 660–680°C at 4.4–4.5 kbar for the retrograde M3 (symplectite) assemblages. These rocks are thus determined to have undergone metamorphism with clockwise P–T paths involving nearly isothermal decompression (ITD) segments, which is inferred to be related to the amalgamation of the
Eastern and Western Blocks to form the coherent basement of the North China Craton along the Trans-North China Orogen in the
late Paleoproterozoic (1.88–1.85 Ga). 相似文献
7.
The impact of trade on the environment and the climate has become a focus of attention. Tending to develop industries with higher added values, developed countries rely on importing high energy consumption goods from developing countries, and however, some CO2 emissions are embodied in the process of import. Currently, the accounting method of the territorial responsibility used to get the international data of greenhouse gas inventories ignores the difference between domestic consumption and export demands. Thus, developing countries bear the responsibility of pollution emissions from the export. The steel industry is an important basic industry of China’s national economy as well as a vital part in the industrial system. With the expansion of trade scale, the impact of the export and import of China’s steel on CO2 emissions is growing. This paper studied the embodied CO2 emissions in the trade of China’s steel from 2005 to 2014, using the input–output model and the trade data of the China’s steel imports and exports. The results indicate that (1) the complete CO2 emissions of China’s steel industry are high. (2) The increase in the export scale makes the embodied CO2 emissions in the trade of China’s steel export increase, and (3) China is a net exporter of CO2 emissions in the steel trade. Especially after 2007, the value of China’s steel exports has been larger than that of China’s steel imports, so China had borne much CO2 emissions responsibility in the trade of China’s steel. Therefore, this paper puts forward that, in the future, the export structure of goods should be optimized into the high-tech products with the high added value, low energy consumption and low carbon emissions, and meanwhile, service industry is promoted to improve technical support to reduce CO2 emissions in the steel industry. 相似文献
8.
9.
Reliable age estimation was obtained originally in this study for gold mineralization of the Malomyr deposit (the eastern part of the Mongolian–Okhotsk foldbelt), which is one of the most well-known deposits in the Russian Far East. The data obtained show that the age of hydrothermal process that resulted in the formation of the Malomyr deposit may be estimated as ~133–132 Ma. Data on magmatism of the same age within the considered region are absent. In the opinion of the authors, mobilization, redistribution of the ore material, and the formation of the Malomyr deposit were mostly controlled by dislocation processes accompanied by hydrothermal activity, which is supported by the results of structural studies. 相似文献
10.
Isotopic compositions of carbon (δ13C from −51.4 to −10.8
PDB) and oxygen (δ18O from 14.4 to 21.4
SMOW) were studied in rhodochrosite and calcite from manganese ores in the South Faizuly and Kyzyltash deposits of the southern Urals. The geological, petrographic, and isotopic data indicate that the studied carbonates are diagenetic formations. It is suggested that the main ore element (Mn) was delivered to the marine basin with hydrothermal solutions percolating in the oceanic crust. Manganese precipitated on the oceanic bottom as oxides near solution discharge zones. Manganese carbonates formed in sediments as a result of the oxidation of organic matter by manganese oxides. High biological productivity of the environment was caused by proximity to the hydrothermal vent that provided favorable biogeochemical conditions for the development of biocoenosis. Anomalously low 13C values in the South Faizuly deposit testify to the large-scale oxidation of methane in the course of manganese carbonate formation.__________Translated from Litologiya i Poleznye Iskopaemye, No. 4, 2005, pp. 416–429.Original Russian Text Copyright © 2005 by Kuleshov, Brusnitsyn. 相似文献
11.
Experimental data are presented for the solubility of NaNbO3 in the ternary system CaCO3–CaF2–NaNbO3 (or calcite–fluorite–lueshite) over the temperature range 500–1,000°C at 0.1 GPa pressure. Liquidus to solidus phase relationships are given for the pseudo-binary join ([CaCO3]60[CaF2]40)100-x–(NaNbO3)x (0<x<60 wt%). These data show that the maximum solubility of NaNbO3 in these liquids is about 17 wt% (or 13.8 wt% Nb2O5) at approximately 930°C, and is represented by the appearance of pyrochlore as the primary liquidus phase. The sub-liquidus assemblages with decreasing temperature for NaNbO3 contents of 20–50 wt% are: pyrochlore + liquid; pyrochlore + CaF2 + liquid; pyrochlore + CaF2 + CaCO3 + liquid. The solidus assemblage is pyrochlore + CaF2 + CaCO3 at temperatures of approximately 700°C (20 wt% NaNbO3) and 600°C (40 wt% NaNbO3). NaNbO3 is present only in sub-solidus assemblages. These data show that in this fluorine-bearing anhydrous system pyrochlore is the principal Nb-hosting supra-solidus phase, in contrast to fluorine-free hydrous melts from which perovskite-structured compounds crystallize. The crystallization of pyrochlore and/or perovskite-structured compounds from haplocarbonatite liquids is thus considered to be dependent upon the F/OH ratio of the melt. 相似文献
12.
V. N. Golubev E. O. Dubinina I. V. Chernyshev T. A. Ikonnikova 《Doklady Earth Sciences》2016,466(1):28-31
The uneven character of the distribution of 18O/16O and 234U/238U values was established in the vertical cross section of the productive sequence of the Dybryn uranium deposit (Vitim uranium-ore region, Buryatia). Both a deficiency and an excess of 234U in relation to the equilibrium 234U/238U ratio in the vertical sequence may provide evidence for the extremely low rate of the infiltration water flow. The behavior of oxygen isotope characteristics for different size fractions of terrigenous rocks provides evidence for active uranium redistribution and openness of the isotope system of this element during interaction of terrigenous–sedimentary rocks with infiltration waters. 相似文献
13.
The Las Colinas landslide, which was triggered by the 13 January 2001, Mw?=?7.7 El Salvador earthquake, was highly destructive. The local site is composed of pyroclastic flows, brown cinders, soft pyroclastic fall deposits and a thin palaeosol and is characterised by steep slopes. The extremely high ground motions recorded near the landslide location are assumed to be both produced by site effects and responsible for the landslide. To characterise the ground motion amplifications due to site effects in terms of the variation in geometrical and geological settings, parametric studies were conducted with a linear elastic slope model, which was vertically subjected to the scattering SV wave of the Gabor wavelet. The results show that a maximum amplification is obtained when the model slope angle is approximately 30° (similar to the actual slope angle), and the maximum amplification is located approximately 20 m behind the crest, where the actual movement was initiated. Additionally, a slope with a height of approximately 160 m enhances ground motion amplification. The subsurface geology is found to induce a greater effect on amplification than that of the slope topography. In particular, a soft pyroclastic fall deposit is observed to contribute most of the ground motion amplification. According to the numerical results, it can be concluded that the local site conditions induced extremely high ground motions that then contributed to the slope movement. Although the thin, buried layer of palaeosol did not cause any significant amplification, its weak cohesion enhanced movement. 相似文献
14.
G. Ottonello B. Civalleri J. Ganguly M. Vetuschi Zuccolini Y. Noel 《Physics and Chemistry of Minerals》2009,36(2):87-106
Thermophysical properties of the various polymorphs (i.e. α-, β- and γ) of Mg2SiO4 were computed with the CRYSTAL06 code within the framework of CO-LCAO-GTF approach by using the hybrid B3LYP density functional
method. Potential wells were calculated through a symmetry preserving, variable cell-shape structure relaxation procedure.
Vibrational frequencies were computed at the long-wavelength limit corresponding to the center of the Brillouin zone (k → 0). Thermodynamic properties were estimated through a semiclassical approach that combines B3LYP vibrational frequencies
for optic modes and the Kieffer’s model for the dispersion relation of acoustic modes. All computed values except volume (i.e.
electronic energy, zero point energy, optical vibrational modes, thermal corrections to internal energy, standard state enthalpy
and Gibbs free energy of reaction, bulk modulus and its P and T derivatives, entropy, C
V, C
P) are consistent with available experimental data and/or reasonable estimates. Volumes are slightly overestimated relative
to those determined directly by X-ray diffraction. A set of optimized volumetric properties that are consistent with the other
semiclassical properties of the phases α, β and γ have been derived by optimization procedure such that the calculated boundaries
for the α/β and β/γ equilibria have the best overall agreement with the experimental data for these transitions.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
相似文献
G. OttonelloEmail: |
15.
This work reports the results of lithological and isotopic study of carbonate rocks from the Pechishchi stratotype section
(Kazan) and three adjacent sections of Kazanian rocks of the Volga-Vyatka region at the eastern Russian Platform. These sections
were recovered by the Kremeshki, Popovtsevo, and Chimbulat quarries (near the town of Sovetsk, southeastern Kirov district).
Lithological features and wide variations of δ13C (from −6.0 to 6.8‰) and δ18 O (from 22.9 to 33.4 ‰) indicate that the rocks were formed in a shallow-marine basin with rapidly varying conditions of
sedimentation which characterize different facies (and/or paleoecological) zones: lagoonal, supralittoral, littoral, shoal.
They also suggest processes of postsedimentary alteration (mainly, under supergene conditions). Numerous short-term hiatuses
are also recorded. 相似文献
16.
Under neoliberal schemes like audit systems, consumer demands born of concerns about food safety, the environment and animal welfare are theoretically poised to influence agricultural production systems (Campbell and Le Heron, 2007). Whether such influences might reverse or redirect the trend toward environmentally-damaging rampant productivism of the 20th century hinges in part on the subjective positions of farmers and the ways in which they inform how farmers respond to policy and market signals.In this paper we argue the need for a genuine engagement with both the complexities of farmer subjectivity and the interactions amongst farmer subjectivity and agro-ecologies, and animal bodies in particular. This paper presents a case study of sheep farmers on the South Island that reveals contestation and transitions in traditional markers of “good farming”, particularly animal health. We observe how such transitions arise from reconfigurations of the relationships between agro-ecological, political and social histories. In this paper’s formulation, neither state subsidies nor neoliberalism in agriculture is primary cause or ultimate effect of the transformation of agricultural practice. Rather, changes in the political economy expose contradictions in farmer subjectivities, the resolution of which may block or reinforce trends suggested by the political economy. We suggest that contested ideas about animal health within the social field of pastoral farming in New Zealand makes it possible that New Zealand’s sheep growers may take the high road of best environmental practice via highly audited environmental standards of production demanded by elite consumer markets, or that they may remain in the intensifying trajectory of continuing to drive the sheep’s body to its maximum possible intensity of production. The mixed legacy of neoliberal reform is that it has simultaneously enabled both of these contradictory trajectories in New Zealand pastoralism. 相似文献
17.
《Applied Geochemistry》2001,16(7-8):719-743
Tin has a larger number of its organometallic derivatives in commercial use than any other element. This has given rise to an increase of the worldwide production of organotin compounds during the last 50 years. Due to the wide industrial applications considerable amounts of the organotins have entered various ecosystems. While Sn in its inorganic form is considered to be non-toxic, the toxicological pattern of the organotin compounds is complex. Depending on the nature and the number of the organic groups bound to the Sn cation, some organotins show specific toxic effects to different organsims even at very low concentrations. Therefore, specific determination of the individual organotin compounds is required. In recent years new sensitve analytical techniques have been developed for the detection of organotin compounds in various environmental samples. High amounts of the toxic tributyltin and some other organotin derivatives can be found not only in water and sediments, but also various aquatic organisms and tissues of mammals and birds are contaminated by these compounds. First investigations of human blood and livers show enhanced concentrations for some organotin derivatives. In spite of legislative regulations of usage for organotins in numerous countries, these pollutants represent a risk for aquatic and terrestric ecosystems. 相似文献
18.
Phase equilibria in the system CaO–MgO–SiO2–CO2–H2O–NaCl are calculated to illustrate phase relations in metacarbonates over a wide-range of P–T–X[H2O–CO2–NaCl] conditions. Calculations are performed using the equation of state of Duan et al. (Geochim Cosmochim Acta 59:2869–2882, 1995) for H2O–CO2–NaCl fluids and the internally consistent data set of Gottschalk (Eur J Mineral 9:175–223, 1997) for thermodynamic properties of solids. Results are presented in isothermal-isobarical plots showing stable mineral assemblages as a function of fluid composition. It is shown that in contact-metamorphic P–T regimes the presence of very small concentrations of NaCl in the fluid causes almost all decarbonation reactions to proceed within the two fluid solvus of the H2O–CO2–NaCl system. Substantial flow of magma-derived fluids into marbles has been documented for many contact aureoles by shifts in stable isotope geochemistry of the host rocks and by the progress of volatile-producing mineral reactions controlled by fluid compositions. Time-integrated fluid fluxes have been estimated by combining fluid advection/dispersion models with the spatial arrangement of mineral reactions and isotopic resetting. All existing models assume that minerals react in the presence of a single phase H2O–CO2 fluid and do not allow for the effect that fluid immiscibility has on the flow patterns. It is shown that fluids emanating from calc-alkaline melts that crystallize at shallow depths are brines. Their salinity may vary depending mainly on pressure and fraction of crystallized melt. Infiltration-driven decarbonation reactions in the host rocks inevitably proceed at the boundaries of the two fluid solvus where the produced CO2 is immiscible and may separate from the brine as a low salinity, low density H2O–CO2 fluid. Most parameters of fluid–rock interaction in contact aureoles that are derived from progress of mineral reactions and stable isotope resetting are probably incorrect because fluid phase separation is disregarded. 相似文献
19.
We present a model that may explain deep crustal earthquakes observed, in particular, in several areas of highly reflective (laminated) lower continental crust. We combine observations from earthquake seismology, crustal reflection seismics and tectonic-rheological concepts. The study concentrates on parts of the northern Alpine foreland where many earthquakes occur inside the laminated lower crust, which is generally considered to be warm and weak. Thin mafic/ultramafic, sill-like intrusions and invisible dykes are assumed to form a corset-like network with high strength. This model can explain the observed strong and multiple reflections and the occurrence of rupture inside a stable structure within a weak lower crust. Tectonic stress transfer (from the Alpine collision zone or/and the Upper Rhine Graben) and its release may follow classical friction concepts. In addition, the heterogeneity of the laminated lower crust may also favour various viscous instabilities. 相似文献
20.
The crystal structure of chromite FeCr2O4 was investigated to 13.7 GPa and ambient temperature with single-crystal X-ray diffraction techniques. The unit-cell parameter
decreases continuously from 8.3832 (5) to 8.2398 (11) Å up to 11.8 GPa. A fit to the Birch–Murnaghan equation of state (EoS)
based on the P–V data gives: K
0 = 209 (13) GPa, K′ = 4.0 (fixed), and V
0 = 588 (1) Å3. The FeO4 tetrahedra and CrO6 octahedra are compressed isotropically with pressure with their Fe–O and Cr–O bond distances decreasing from 1.996 (6) to
1.949 (7) Å and from 1.997 (3) to 1.969 (7) Å, respectively. The tetrahedral site occupied by the Fe2+ cation is more compressible than the octahedral site occupied by the Cr3+ cation. The resulting EoS parameters for the tetrahedral and the octahedral sites are K
0 = 147 (9) GPa, K′ = 4.0 (fixed), V
0 = 4.07 (1) Å3 and K
0 = 275 (24) GPa, K′ = 4.0 (fixed), V
0 = 10.42 (2) Å3, respectively. A discontinuous volume change is observed between 11.8 and 12.6 GPa. This change indicates a phase transition
from a cubic (space group Fd-[`3]{\overline{3}}
m) to a tetragonal structure (space group I41
/amd). At the phase transition boundary, the two Cr–O bonds parallel to the c-axis shorten from 1.969 (7) to 1.922 (17) Å and the other four Cr–O bonds parallel to the ab plane elongate from 1.969 (7) to 1.987 (9) Å. This anisotropic deformation of the octahedra leads to tetragonal compression
of the unit cell along the c-axis. The angular distortion in the octahedron decreases continuously up to 13.7 GPa, whereas the distortion in the tetrahedron
rises dramatically after the phase transition. At the pressure of the phase transition, the tetrahedral bond angles along
the c-axis direction of the unit cell begin decreasing from 109.5° to 106.6 (7)°, which generates a “stretched” tetrahedral geometry.
It is proposed that the Jahn–Teller effect at the tetrahedrally coordinated Fe2+ cation becomes active with compression and gives rise to the tetrahedral angular distortion, which in turn induces the cubic-to-tetragonal
transition. A qualitative molecular orbital model is proposed to explain the origin and nature of the Jahn–Teller effect observed
in this structure and its role in the pressure-induced phase transition. 相似文献