11,314 research outputs found
Sintering characteristics and properties of PuS and PuP are determined
Report on the preparation of plutonium monosulphide and plutonium monophosphide includes a description of the sintering characteristics and properties of these high-temperature compounds. data on weight loss, microstructure, density, melting point, thermal expansion, microhardness, Seebeck coefficient, and thermal diffusion are included
Laboratory arc furnace features interchangeable hearths
Laboratory arc furnace using rapidly interchangeable hearths gains considerable versatility in casting so that buttons or special shaped castings can be produced. It features a sight glass for observation
Josephson tunneling of dark solitons in a double-well potential
We study the dynamics of matter waves in an effectively one-dimensional
Bose-Einstein condensate in a double well potential. We consider in particular
the case when one of the double wells confines excited states. Similarly to the
known ground state oscillations, the states can tunnel between the wells
experiencing the physics known for electrons in a Josephson junction, or be
self-trapped. As the existence of dark solitons in a harmonic trap are
continuations of such non-ground state excitations, one can view the
Josephson-like oscillations as tunnelings of dark solitons. Numerical existence
and stability analysis based on the full equation is performed, where it is
shown that such tunneling can be stable. Through a numerical path following
method, unstable tunneling is also obtained in different parameter regions. A
coupled-mode system is derived and compared to the numerical observations.
Regions of (in)stability of Josephson tunneling are discussed and highlighted.
Finally, we outline an experimental scheme designed to explore such dark
soliton dynamics in the laboratory.Comment: submitte
A Comparison of Quartz Crystal Microbalance Measurements with Mass Spectrometer Determinations
An experimental program was undertaken in which mass accretion rates, as determined by a liquid nitrogen cooled quartz crystal microbalance, were compared with the mass flux rates, as determined by both a cycloidal type and a quadrupole type residual gas analyzer for five simple materials. The data indicate a high degree of correlation between these instruments insofar as the shape of the curves. There are large variations however among the absolute values
Estimation of outgassing from an expended apogee motor and its effects on spacecraft surfaces
An experimental and theoretical investigation was carried out to evaluate the degradation of the solar cells and other sensitive surfaces of a spacecraft, resulting from the molecular outgassing of an expended solid propellant apogee motor. The motor, following its burnout, is retained by the spacecraft and is a source of gases and particulates which will be released mainly by the unburned propellant-to-casing insulation. The deployment of the solar array within a few minutes after the motor burn results in the interception and reflection to the surfaces of the spacecraft of the molecular outgassing and particulates. Various methods, based on some experimental data, were used to analytically assess the magnitude of the outgassing from the engine
OSS-1/contamination monitor
A 20-cm high, 18-cm wide, and 30-cm long (8x7x12 inch) box weighing about 7 kg (15 lbs) and consuming about 7 watts of power was carried on the OSS-1 pallet to monitor the mass build-up or accretion of condensible, volatile materials on surfaces in the shuttle bay during all phases of ascent, on-orbit, and descent. Passively thermally controlled, the box holds two witness samples and four actively temperature controlled quartz crystal microbalances (TQCM) whose temperature can vary from -60 C to +80 C. Graphs show the accretion indicated by the TQCM during the launch and early orbital phase. Conditions during tail to the Sun, nose to the Sun, and bay to the Sun attitudes of the shuttle during STS-3 are reflected in temperatures indicated by the OSS-1 thermistor. These temperatures influence outgassing rates of various materials as well as measurements made by the contamination monitor package. The parameters that bear on TQCM measurements data are shown in graphs and discussed
Mindfulness: A foothold for Rogers's humanistic person-centred approach
This article probed and contextualised the strong parallels between meditation derived mindfulness and Rogers's humanistic person-centred (PC) approach. This was done through a conceptual and evaluative literature review of the PC framework in relation to definitive descriptions of mindfulness. Elements of mindfulness within the core conditions of PC therapy were explored and verified. Quotations, pragmatic, behavioural descriptions and explications provided evidence of a shared ideology inherent in both concepts via “way of being”. The findings suggested that mindfulness cultivates, harmonises and deepens essential therapist qualities in PC therapy. This review article could supply a rationale for significant inferences in the implementation of meditation-inspired activities in the practical preparation of trainee therapists as well as optimising proficiency and refinement in professional practice
Die toekoms van die Afrikaanse lewenstyl in die nuwe wĂŞreld
U, as vooraanstaande Afrikaners, het seker almal ’n week of twee gelede, toe die Beurs in ’n windstilte gelê het, aandele gekoop. Dan het u voldoen aan die eerste groot verandering in die Afrikaanse lewenstyl van ons nuwe wêreld — sakebewustheid. Ek wens ek was dertig ja a r jonger om met u op hierdie wittebrood van die ontwikkelende Suid-Afrika te gaan
Reassembling and remembering-the politics of reconciliation in South Africa
This article proposes that the work of the French sociologist of science, Bruno Latour, that conceptualises the political process in a highly pluralist society, can provide a useful starting point for a discussion on the politics of reconciliation. It is especially Latour’s suggestion of an object-oriented politics that will be explored and applied to the South African situation. Subsequently, however, it is argued that Latour’s politics of “reassembling” should be complemented by a politics of remembering. The latter notion is understood in a Platonic-Augustinian fashion – following the interpretation of the contemporary philosophical-theological movement of Radical Orthodoxy – as a diffuse recognition of the other within the self, whereby the politics of reconciliation is, in an important sense, broadened to encompass the interior, psychic and, ultimately, spiritual aspects of the relation between the self and the other. The paper concludes with some remarks on the role of the church as the narrative embodiment of reconciliation conceived as reassembling ánd remembering
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