9,762 research outputs found
Reviews
Reviews of Employment Contracts: New Zealand Experiences, Workplace Industrial Relations: Australian Case Studies, Life and Death at Work: Industrial Accidents as a Case of Socially Produced Erro
The effect of Mg location on Co-Mg-Ru/γ-Al2O3 Fischer–Tropsch catalysts
© 2016 The Author(s) Published by the Royal Society. All rights reserved.The effectiveness of Mg as a promoter of Co-Ru/γ-Al2O3 Fischer-Tropsch catalysts depends on how and when the Mg is added. When the Mg is impregnated into the support before the Co and Ru addition, some Mg is incorporated into the support in the form of MgxAl2O3+x if the material is calcined at 550°C or 800°C after the impregnation, while the remainder is present as amorphous MgO/MgCO3 phases. After subsequent Co-Ru impregnation MgxCo3-xO4 is formed which decomposes on reduction, leading to Co(0) particles intimately mixed with Mg, as shown by high-resolution transmission electron microscopy. The process of impregnating Co into an Mg-modified support results in dissolution of the amorphous Mg, and it is this Mg which is then incorporated into MgxCo3-xO4. Acid washing or higher temperature calcination after Mg impregnation can remove most of this amorphous Mg, resulting in lower values of x in MgxCo3-xO4. Catalytic testing of these materials reveals that Mg incorporation into the Co oxide phase is severely detrimental to the site-Time yield, while Mg incorporation into the support may provide some enhancement of activity at high temperature
Changes in the Relative Density of Swamp Wallabies (Wallabia bicolor) and Eastern Grey Kangaroos (Macropus giganteus) in Response to Timber Harvesting and Wildfire
Наукова спадщина О.О. Русова в контексті актуальних проблем української етнології
У лютому виповнилося 160 років з дня народження відомого вченого, етнографа, статистика та громадського діяча Олександра Русова.This article is devoted to the famous scholar, ethnographer, civil activist Oleksandr Rusov. All his work was concentrated on the study of Ukrainian folk, their history, life style and language. Among his most prominent works was the foundation of the statistics as the scholarly discipline and its use for the ethnographical studies. Special attention deserves his work “The Statistics of the Ukrainian Population of the European Russia”. His data on Ukrainian and Russian population in various regions at different historical times are very valuable for the contemporary scholars. He actively participated in Ukrainian cultural life: he was the organizer of the first Ukrainian plays on Kyiv stages, the editor of Prague edition of “Kobzar”, and participated in different social and cultural organizations
Restriction categories III: colimits, partial limits, and extensivity
A restriction category is an abstract formulation for a category of partial
maps, defined in terms of certain specified idempotents called the restriction
idempotents. All categories of partial maps are restriction categories;
conversely, a restriction category is a category of partial maps if and only if
the restriction idempotents split. Restriction categories facilitate reasoning
about partial maps as they have a purely algebraic formulation.
In this paper we consider colimits and limits in restriction categories. As
the notion of restriction category is not self-dual, we should not expect
colimits and limits in restriction categories to behave in the same manner. The
notion of colimit in the restriction context is quite straightforward, but
limits are more delicate. The suitable notion of limit turns out to be a kind
of lax limit, satisfying certain extra properties.
Of particular interest is the behaviour of the coproduct both by itself and
with respect to partial products. We explore various conditions under which the
coproducts are ``extensive'' in the sense that the total category (of the
related partial map category) becomes an extensive category. When partial
limits are present, they become ordinary limits in the total category. Thus,
when the coproducts are extensive we obtain as the total category a lextensive
category. This provides, in particular, a description of the extensive
completion of a distributive category.Comment: 39 page
HST Grism Observations of a Gravitationally Lensed Redshift 10 Galaxy
We present deep spectroscopic observations of a Lyman-break galaxy candidate
(hereafter MACS1149-JD) at with the Space
Telescope () WFC3/IR grisms. The grism observations were taken at
4 distinct position angles, totaling 34 orbits with the G141 grism, although
only 19 of the orbits are relatively uncontaminated along the trace of
MACS1149-JD. We fit a 3-parameter (, F160W mag, and Ly equivalent
width) Lyman-break galaxy template to the three least contaminated grism
position angles using an MCMC approach. The grism data alone are best fit with
a redshift of ( confidence), in
good agreement with our photometric estimate of
( confidence). Our analysis
rules out Lyman-alpha emission from MACS1149-JD above a equivalent
width of 21 \AA{}, consistent with a highly neutral IGM. We explore a scenario
where the red /IRAC color of the galaxy
previously pointed out in the literature is due to strong rest-frame optical
emission lines from a very young stellar population rather than a 4000 \AA{}
break. We find that while this can provide an explanation for the observed IRAC
color, it requires a lower redshift (), which is less preferred
by the imaging data. The grism data are consistent with both
scenarios, indicating that the red IRAC color can still be explained by a 4000
\AA{} break, characteristic of a relatively evolved stellar population. In this
interpretation, the photometry indicate that a Myr stellar
population is already present in this galaxy only after
the Big Bang.Comment: Accepted to ApJ. This is the accepted versio
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