58,235 research outputs found
Far infrared spectra of amorphous and crystalline water ice and changes in these phases as the result of proton irradiation
Far infrared spectra from 20 microns (500 cm(sup -1)) to 100 microns (100 cm(sup -1)) of water ice were measured. Amorphous ice deposited at 13 K has one absorption band at 45 microns (220 cm(sup -1)). Amorphous ice evolves into a crystalline form with absorptions at 44 microns (229 cm(sup -1)) and 62 microns (162 cm(sup -1)) as the temperature is increased to 155 K. Spectra documenting this phase change are presented as well as spectra of crystalline ice at temperatures between 13 K and 155 K. Far infrared spectra of amorphous and crystalline water ice before and after proton irradiation are also presented. Changes in these two forms are discussed in relation to ices in comets, grains, and planetary satellites in various radiation environments. Observations of non-terrestrial clathrate hydrates are still lacking despite the fact that clathrates first were suggested to exist in cometary and interstellar ices over forty years ago. Spectroscopy, the most direct method of astronomical detection, has been hampered by the similarity of clathrate hydrate spectra to those of unenclathrated guest molecules and solid H2O. A methanol (CH3OH) clathrate hydrate, using a recently published procedure, was prepared and its far-IR spectrum investigated. The spectrum is quite differenct from that of either unenclathrated CH3OH or solid H2O and so should be of value in astronomical searches for this clathrate
Sosa, Customary International Law, and the Continuing Relevance of Erie
Ten years ago, the conventional wisdom among international law academics was that customary international law (CIL) had the status of self-executing federal common law to be applied by courts without any need for political branch authorization. This modern position came under attack by so-called revisionist critics who argued that CIL had the status of federal common law only in the relatively rare situations in which the Constitution or political branches authorized courts to treat it as such. Modern position proponents are now claiming that the Supreme Court\u27s 2004 decision in Sosa v. Alvarez-Machain confirms that CIL has the status of self-executing federal common law. As this Article explains, the decision in Sosa did not in fact embrace the modern position, and, indeed, is best read as rejecting it. Commentators who construe Sosa as embracing the modern position have confounded the automatic incorporation of CIL as domestic federal law in the absence of political branch authorization (i.e., the modern position) with the entirely different issue of whether and to what extent a particular statute, the Alien Tort Statute ( ATS ), authorizes courts to apply CIL as domestic federal law. The Article also explains how CIL continues to be relevant to domestic federal common law despite Sosa\u27s rejection of the modern position. The fundamental flaw of the modern position is that it ignores the justifications for, and limitations on, post-Erie federal common law. As the Article shows, however, there are a number of contexts in addition to the ATS in which it is appropriate for courts to develop federal common law by reference to CIL, including certain jurisdictional contexts not amenable to state regulation (namely admiralty and interstate disputes), and gap-filling and interpretation of foreign affairs statutes and treaties. The Article concludes by considering several areas of likely debate during the next decade concerning the domestic status of CIL: corporate aiding and abetting liability under the ATS; application of CIL to the war on terrorism; and the use of foreign and international materials in constitutional interpretation
Globalization, NGOs and Multi-Sectoral Relations
This paper seeks to make sense of the impact of globalization on nonprofit, nongovernmental organizations. We argue that globalization processes have contributed to the rising numbers and influence of NGOs in many countries, and particularly in the international arena. International NGOs and NGO alliances are emerging as increasingly influential players in international decision-making, and we discuss some of the roles they can be expected to play in the future. We consider whether the emergence of domestic and international NGOs as important policy makers strengthens or weakens the future of democratic accountability, and we suggest several patterns of interaction among civil society, government and business in future governance issues.This publication is Hauser Center Working Paper No. 1. The Hauser Center Working Paper Series was launched during the summer of 2000. The Series enables the Hauser Center to share with a broad audience important works-in-progress written by Hauser Center scholars and researchers
Infall near clusters of galaxies: comparing gas and dark matter velocity profiles
We consider the dynamics in and near galaxy clusters. Gas, dark matter and
galaxies are presently falling into the clusters between approximately 1 and 5
virial radii. At very large distances, beyond 10 virial radii, all matter is
following the Hubble flow, and inside the virial radius the matter particles
have on average zero radial velocity. The cosmological parameters are imprinted
on the infall profile of the gas, however, no method exists, which allows a
measurement of it. We consider the results of two cosmological simulations
(using the numerical codes RAMSES and Gadget) and find that the gas and dark
matter radial velocities are very similar. We derive the relevant dynamical
equations, in particular the generalized hydrostatic equilibrium equation,
including both the expansion of the Universe and the cosmological background.
This generalized gas equation is the main new contribution of this paper. We
combine these generalized equations with the results of the numerical
simulations to estimate the contribution to the measured cluster masses from
the radial velocity: inside the virial radius it is negligible, and inside two
virial radii the effect is below 40%, in agreement the earlier analyses for DM.
We point out how the infall velocity in principle may be observable, by
measuring the gas properties to distance of about two virial radii, however,
this is practically not possible today.Comment: 7 pages, 3 figures, to appear in MNRA
The 2-D magnetohydrostatic configurations leading to flares or quiescent filament eruptions
To investigate the cause of flares and quiescent filament eruptions the quasi-static evolution of a magnetohydrostatic (MHS) model was studied. The results lead to a proposal that: the sudden disruption of an active-region filament field configuration and the accompanying flare result from the lack of a neighboring equilibrium state as magnetic shear is increased above the critical value; and a quiescent filament eruption is due to an ideal MHD kink instability of a highly twisted detached flux tube formed by the increase of plasma current flowing along the length of the filament. A numerical solution was developed for the 2-D MHS equation for the self-consistent equilibrium of a filament and overlying coronal magnetic field. Increase of the poloidal current causes increase of magnetic shear. As shear increases past a critical point, there is a discontinuous topological change in the equilibrium configuration. It was proposed that the lack of a neighboring equilibrium triggers a flare. Increase of the axial current results in a detached tube with enough helical twist to be unstable to ideal MHD kink modes. It was proposed that this is the condition for the eruption of a quiescent filament
Creep behavior of niobium alloy PWC-11
The high vacuum creep and creep-rupture behavior of a Nb-1Zr-.1C alloy (PWC 11) was investigated at 1350 and 1400 K with an applied stress of 40 MPa. The material was tested in the following four conditions: annealed (1 hr 1755 K/2 hr 1475 K); annealed plus EB welded; annealed plus aged for 1000 hr at 1350 or 1400 K; and annealed, welded, and aged. It was found that the material in the annealed state was the most creep-resistant condition tested, and that aging the alloy for 1000 hr without an applied stress greatly reduced that strength; however, it was still approximately three times as creep resistant as Nb-1Zr. Additionally, the EB weld region was stronger than the base metal in each condition tested, and phase extraction of the dispersed precipitate revealed the presence of a 70%ZrC-30%NbC cubic monocarbide phase
Magnetic Suspension and Balance Systems: A Comprehensive, Annotated Bibliography
This bibliography contains 301 entries. Results are reported of recent studies aimed at increasing the research capabilities of magnetic suspension and balance systems; e.g., increasing force and torque capability, increasing angle of attack capability, and increasing overall system reliability. The problem is addressed of scaling from the relatively small size of existing systems to much larger sizes. The purpose of the bibliography is to provide an up-to-date list of publications that might be helpful to persons interested in magnetic suspension and balance systems for use in wind tunnels. The arrangement is generally chronological by date of presentation. However, papers presented at conferences or meetings are placed under dates of presentation. The numbers assigned to many of the citations have been changed from those used in the previous bibliography. This has been done in order to allow outdated citations to be removed and some recently discovered older works to be included in their proper chronological order. Author, source, and subject indexes are included in order to increase the usefulness of this compilation
Analysis of the effectiveness of industrial R and D
The criteria used by private industry in evaluating and selecting proposed research and development projects for implementation, and also in determining which R and D facilities are to be acquired were investigated. Conceptual and practical issues inherent in any quantitative analysis of the contribution of R and D to economic growth were identified in order to assist NASA in developing approaches for analzying the economic implication of its own R and D efforts
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