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261.
This paper examines how bilateral ties between developed (home) countries and developing (host) countries influence the location of Clean Development Mechanism projects (CDMs). With the home-host country pair as the unit of analysis (2,058 country-pairs), we employ a logistic regression model to analyze decisions of home countries in selecting the location for their CDMs. We are most interested in examining how home countries’ familiarity with the host country influences CDM location decisions. The familiarity factors are: (1) colonial history; (2) bilateral trade; and (3) bilateral aid. Using a binary logistical model, we find that that bilateral familiarity factors strongly influence CDM location decisions. Further, with respect to host country characteristics, we find that total carbon dioxide emissions and UNFCCC specific domestic institutions influence CDM location decisions, but not general investment institutions or high carbon intensity of host country economies. 相似文献
262.
N. Muhr A. M. Veronig I. W. Kienreich B. Vršnak M. Temmer B. M. Bein 《Solar physics》2014,289(12):4563-4588
We statistically analyzed the kinematical evolution and wave pulse characteristics of 60 strong large-scale EUV wave events that occurred during January 2007 to February 2011 with the STEREO twin spacecraft. For the start velocity, the arithmetic mean is 312±115 km?s?1 (within a range of 100?–?630 km?s?1). For the mean (linear) velocity, the arithmetic mean is 254±76 km?s?1 (within a range of 130?–?470 km?s?1). 52 % of all waves under study show a distinct deceleration during their propagation (a≤?50 m?s?2), the other 48 % are consistent with a constant speed within the uncertainties (?50≤a≤50 m?s?2). The start velocity and the acceleration are strongly anticorrelated with c≈?0.8, i.e. initially faster events undergo stronger deceleration than slower events. The (smooth) transition between constant propagation for slow events and deceleration in faster events occurs at an EUV wave start-velocity of v≈230 km?s?1, which corresponds well to the fast-mode speed in the quiet corona. These findings provide strong evidence that the EUV waves under study are indeed large-amplitude fast-mode MHD waves. This interpretation is also supported by the correlations obtained between the peak velocity and the peak amplitude, impulsiveness, and build-up time of the disturbance. We obtained the following association rates of EUV wave events with other solar phenomena: 95 % are associated with a coronal mass ejection (CME), 74 % to a solar flare, 15 % to interplanetary type II bursts, and 22 % to coronal type II bursts. These findings are consistent with the interpretation that the associated CMEs are the driving agents of the EUV waves. 相似文献
263.
Natalia S. Bezaeva Dmitry D. Badyukov Mikhail A. Nazarov Pierre Rochette Joshua M. Feinberg Gennadiy P. Markov Daniel Borschneck François Demory Jérôme Gattacceca Sergey E. Borisovskiy Anna Ya Skripnik 《Meteoritics & planetary science》2014,49(6):958-977
Here we characterize the magnetic properties of the Chelyabinsk chondrite (LL5, S4, W0) and constrain the composition, concentration, grain size distribution, and mineral fabric of the meteorite's magnetic mineral assemblage. Data were collected from 10 to 1073 K and include measurements of low‐field magnetic susceptibility (χ0), the anisotropy of χ0, hysteresis loops, first‐order reversal curves, Mössbauer spectroscopy, and X‐ray microtomography. The REM and REM′ paleointensity protocols suggest that the only magnetizations recorded by the chondrite are components of the Earth's magnetic field acquired during entry into our planet's atmosphere. The Chelyabinsk chondrite consists of light and dark lithologies. Fragments of the light lithology show logχ0 = 4.57 ± 0.09 (s.d.) (n = 135), while the dark lithology shows 4.65 ± 0.09 (n = 39) (where χ0 is in 10?9 m3 kg?1). Thus, Chelyabinsk is three times more magnetic than the average LL5 fall, but is similar to a subgroup of metal‐rich LL5 chondrites (Paragould, Aldsworth, Bawku, Richmond) and L/LL5 chondrites (Glanerbrug, Knyahinya). The meteorite's room‐temperature magnetization is dominated by multidomain FeNi alloys taenite and kamacite (no tetrataenite is present). However, below approximately 75 K remanence is dominated by chromite. The metal contents of the light and dark lithologies are 3.7 and 4.1 wt%, respectively, and are based on values of saturation magnetization. 相似文献
264.
Milan Burša 《Earth, Moon, and Planets》1995,71(1-2):59-64
It has been proved that the geoidal valueW
0 is not dependent on the system used for defining the geoid surface. It is the same for the zero-frequency tidal system, mean system and tide-free system. It has been suggested,W
0 be adopted as primary constant defining the length dimensions of celestial bodies. 相似文献
265.
Zdeněk MikulÁšek Luboš Kohoutek Miloslav Zejda Ondřej Pejcha 《Astrophysics and Space Science》2005,296(1-4):465-468
We confirm the presence of regular UBV(RI)C light variations of the object in the center of the planetary nebula Sh 2-71, with an improved period of P = 68.132 ± 0.005 days. The shapes and amplitudes of light curves, in particular colours, are briefly discussed. 相似文献
266.
J. Vranješ 《Astrophysics and Space Science》1990,173(2):293-298
Gravitational instability of small perturbations propagating through the central area of a gas cloud is discussed regarding the basic state and taking into account radiative pressure. Instability criterion similar to Jean's one is obtained and it was shown that the inhomogeneity can act in two ways, to stabilize or destabilize the system, depending on the value of the second derivative of the basic state temperature. 相似文献
267.
B. Vršnak 《Solar physics》1984,94(2):289-297
Oscillatory motions of a loop prominence observed on July 17, 1981 are analysed. The oscillations were mainly horizontal, with a period of 8 min. Restoring force was a result of magnetic tension, and assuming a simplified magnetic field configuration the expression for frequencies of oscillations is derived and compared with the observations. Taking the observed period, the strength of the magnetic field permeating the prominence is estimated as 45 G. Finally, the stability of the prominence is discussed. 相似文献
268.
M. Burša 《Earth, Moon, and Planets》1983,28(1):49-53
The concept “the tidal force function of the Earth-Moon system” is introduced and its exact determination based on the Stokes constants (harmonic coefficients) in the external gravitational potential of both bodies is outlined. The exact determination of the torque due to the Moon exerted on the Earth may be performed in terms of the Stokes constants of both bodies and the mutual position of both ellipsoids of inertia. 相似文献
269.
A. Hruška 《Planetary and Space Science》1982,30(7):701-709
A mathematical formalism describing the relation between the structure of a one-fluid, collisionless plasma and the topological features of the vector lines of the magnetic, velocity and electric fields is suggested and a rigorous approach to the problem of determining the local features of the plasma from the properties of the velocity field v, observed at a chosen point of space, is developed. The limits to drawing conclusions from the observational data (such as encountered in magnetospheric physics) are outlined in Section 2.Energization of a plasma during a stationary convection is an example of a process characterized by the properties of the tensor . In particular, if the plasma density and the velocity and pressure components in a volume element of the plasma are known, then the time rates of change of the kinetic and internal energies are described by stretchings of the element and by its shearing in the surface defined by the vectors of magnetic field and perpendicular velocity. Criteria according to which plasma gains or loses kinetic and internal energies are derived. 相似文献
270.
M. Burša S. Kenyon J. Kouba Z. Šíma V. Vatrt V. Vítek M. Vojtíšková 《Studia Geophysica et Geodaetica》2005,49(1):13-22
Estimates of the second tesseral torque due to the variations in the radial space position of the mean ocean surface as monitored by TOPEX/POSEIDON altimeter system are derived. The magnitude of the studied torque may be compared to the tidal torque and to the tesseral torque caused by deformations due to the Earths rotation. However, such torque estimates strongly depend on the thickness of the ocean surface layer adopted in the spherical model of which the dynamics is believed to be responsible for the derived torque. The dependence on the thickness is discussed. 相似文献