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Understanding the impact of volunteering on pro-environmental behavioural change
This article examines whether there is an association between engaging in environmental volunteering activities and pro-environmental behavioural change. Utilising self-reported surveys, the article explores the potential impact that environmental volunteering has on people's pro-environmental behaviours over time, using The Conservation Volunteers' two volunteering programmes – Green Gyms® and Action Teams – as a comparative case study. The findings show a positive association between environmental volunteering activities and a person's self-reported pro-environmental behaviours over time. Further, volunteers presented improved impact across almost all of the eight pro-environmental behaviours measured, with differences observed between the two volunteering programmes as well as sociodemographic groupings
Spectral evidence for carbonates on Mars: Hydrous carbonates
Although many of the spectral features of the Martian samples studied are not unique mineralogical indicators, much of the current spectral data is consistent with (possibly abundant) hydrous carbonates on the surface of Mars. The absorption features in the measured samples were quite weak compared with those of anhydrous carbonates. The weak features imply that significantly more hydrous carbonates can be incorporated onto the surface before becoming spectrally evident; however, exact limits have yet to be determined. The stability of these materials in the Martian environment is not known, but their formation and occurrence in low temperature terrestrial environments makes them appealing candidates for weathering products on Mars
New spectral observations of Callisto and leading/trailing hemisphere distinctions
In December 1989 and January 1990, new observations of the leading and trailing edges of Callisto were made from the NASA Infrared Telescope Facility on Mauna Kea in Hawaii. Using the Cool Grating Array Spectrometer, spectral coverage was obtained from 1.89 to 2.46 microns and from 2.8 to 4.2 microns for both the leading and trailing hemispheres. In addition, spectral coverage of the leading hemisphere was obtained from 1.30 to 2.55 microns and from 4.2 to 4.8 microns. Interpretations of the data are given
Study of fuel cell powerplant with heat recovery
It was shown that heat can be recovered from fuel cell power plants by replacing the air-cooled heat exchangers in present designs with units which transfer the heat to the integrated utility system. Energy availability for a 40-kW power plant was studied and showed that the total usable energy at rated power represents 84 percent of the fuel lower heating value. The effects of design variables on heat availability proved to be small. Design requirements were established for the heat recovery heat exchangers, including measurement of the characteristics of two candidate fuel cell coolants after exposure to fuel cell operating conditions. A heat exchanger test program was defined to assess fouling and other characteristics of fuel cell heat exchangers needed to confirm heat exchanger designs for heat recovery
Average output entropy for quantum channels
We study the regularized average Renyi output entropy \bar{S}_{r}^{\reg} of
quantum channels. This quantity gives information about the average noisiness
of the channel output arising from a typical, highly entangled input state in
the limit of infinite dimensions. We find a closed expression for
\beta_{r}^{\reg}, a quantity which we conjecture to be equal to \Srreg. We
find an explicit form for \beta_{r}^{\reg} for some entanglement-breaking
channels, and also for the qubit depolarizing channel as a
function of the parameter . We prove equality of the two quantities in
some cases, in particular we conclude that for both are
non-analytic functions of the variable .Comment: 32 pages, several plots and figures; positivity condition added for
Theorem on entanglement breaking channels; new result for entrywise positive
channel
Geometric phases and Wannier functions of Bloch electrons in 1-dimension
We present a formal expression for Wannier functions of composite bands of
1-D Bloch electrons in terms of parallel-transported Bloch functions and their
non-Abelian geometric phases. Spatial decay properties of these Wannier
functions are studied in the case of simple bands of 1-D model insulator and
metal. Within first-principles density functional theory, we illustrate the
formalism through the construction of Wannier functions of polyethylene and
polyacetylene.Comment: 4 pages, 4 figure
Antarctic meteorite newsletter. Volume 4: Number 1, February 1981: Antarctic meteorite descriptions, 1976, 1977, 1978, 1979
This issue of the Newsletter is essentially a catalog of all antarctic meteorites in the collections of the Johnson Space Center Curation Facility and the Smithsonian except for 288 pebbles now being classed. It includes listings of all previously distributed data sheets plus a number of new ones for 1979. Indexes of samples include meteorite name/number, classification, and weathering category. Separate indexes list type 3 and 4 chondrites, all irons, all achondrites, and all carbonaceous chondrites
Antarctic meteorite descriptions 1976-1977-1978-1979
All previously distributed meteorite data sheets, plus a number of new ones for 1979 chondrites are included. A comprehensive sample index listing meteorite name/number, classification, and weathering category is also included. Separate indexes listing all petrologic type 3 and type 4 chondrites, all irons, all achondrites, and all carbonaceous chondrites in the collection is provided
Is there further evidence for spatial variation of fundamental constants?
The detection of a spatial variation of the fine-structure constant, alpha,
based on study of quasar absorption systems has recently been reported. The
physics that causes this alpha-variation should have other observable
manifestations, and this motivates us to look for complementary astrophysical
effects. In this paper we propose a method to test whether spatial variation of
fundamental constants existed during the epoch of big bang nucleosynthesis.
Using existing measurements of primordial deuterium abundance we find very weak
indications that such a signature might exist, but the paucity of measurements
precludes any firm conclusion. We also examine existing quasar absorption
spectra data that are sensitive to variation of the electron-to-proton mass
ratio, mu, and x = (alpha^2 mu g_p) for spatial variation.Comment: 6 pages, 1 figur
Evidence for ammonium-bearing minerals in Ceres
Evidence for ammonium-bearing minerals was found on the surface of the largest asteroid Ceres. The presence of ammonium-bearing clays suggests that Ceres has experienced a period of alteration by substantial amounts of an ammonium-bearing fluid. The presence of the ammonium-bearing clays does not preclude Ceres maintaining a volatile inventory in the core or in a volatile-rich zone at some distance below the surface. Telescopic observations of Ceres, using the 3.0 meter NASA Infrared telescope facility prompted this reevaluation of its surface mineralogy
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