530 research outputs found
The reconstruction of Ni and Rh (001) surfaces upon Carbon, Nitrogen, or Oxygen adsorption
Nickel and Rhodium (001) surfaces display a similar - as from STM images -
clock reconstruction when half a monolayer of C/Ni, N/Ni or O/Rh is adsorbed;
no reconstruction is observed instead for O/Ni. Adsorbate atoms sit at the
center of the black squares of a chess-board, , pattern and two
different reconstructions are actually compatible with the observed STM images
- showing a pattern - according to whether a rotation of the
black or white squares occurs. We report on a first - principles study of the
structure of X/Ni(001) and X/Rh(001) surfaces (X=C,N,O) at half a monolayer
coverage, performed using density-functional theory. Our findings are in
agreement with all available experimental information and shed new light on the
mechanisms responsible for the reconstructions. We show that the same substrate
may display different reconstructions - or no reconstruction - upon adsorption
of different atomic species, depending on the relative importance of the
chemical and steric factors which determine the reconstruction.Comment: 18 pages, 5 figure
Summary of time requirements and potential improvements for Marine Recorder data entry.
The contract work has demonstrated that older data can be assessed and entered into the MR format. Older data has associated problems but is retrievable. The contract successfully imported all datasets as required. MNCR survey sheets fit well into the MR format.
The data validation and verification process can be improved. A number of computerised short cuts can be suggested and the process made more intuitive. Such a move is vital if MR is to be adopted as a standard by the recording community both on a voluntary level and potentially by consultancies
Imaging Gaseous Detector based on Micro Processing Technology
The development of gaseous detectors has been exciting again since the
appearance of a MicroStrip Gas Chamber(MSGC) in 1988, which is made using a
micro-electronics technology. These days lots of variations of the advanced
gaseous detectors are being intensively studied in the world.
We have developed the two-dimensional MSGC having a 10 cm square detection
area and the ultra fast readout system for a real time X-ray imaging. The MSGC
was made using Multi-Chip Module (MCM) technology, and has a very thin
substrate of 17 m, lots of thin anodes and back strips both with 200
m pitches. This enables us to get fast digital X-ray images with recording
both the timing and an energy of each X-ray photon. In addition, an
intermediate gas multiplier has been realized using a capillary plate having a
conductive surface of a capillary. The MSGC combined with the conductive
capillary plate can be steadily operated with a high gain under intense
irradiation. Here we also report new approaches of X-ray crystal structure
analyses using timing information obtained by the MSGC.Comment: 14 papges, 10 figures, to appear in the proceedings of Solid State
Detectors for 21st Century (Nucl. Instru. and Meth. A
A First Mass Production of Gas Electron Multipliers
We report on the manufacture of a first batch of approximately 2,000 Gas
Electron Multipliers (GEMs) using 3M's fully automated roll to roll flexible
circuit production line. This process allows low-cost, reproducible fabrication
of a high volume of GEMs of dimensions up to 3030 cm. First tests
indicate that the resulting GEMs have optimal properties as radiation
detectors. Production techniques and preliminary measurements of GEM
performance are described. This now demonstrated industrial capability should
help further establish the prominence of micropattern gas detectors in
accelerator based and non-accelerator particle physics, imaging and
photodetection.Comment: 11 pages, 10 figures, to be submitted to Nucl. Instr. Meth.
Polarization Observables for Two-Pion Production off the Nucleon
We develop polarization observables for the processes
and , using both a helicity and hybrid helicity-transversity
basis. Such observables are crucial if processes that produce final states
consisting of a spin-1/2 baryon and two pseudoscalar mesons are to be fully
exploited for baryon spectroscopy. We derive relationships among the
observables, as well as inequalities that they must satisfy. We also discuss
the observables that must be measured in `complete' experiments, and briefly
examine the prospects for measurement of some of these observables in the near
future.Comment: 20 pages, using revtex
Let's get dangerous â A review of current scholarship in public relation history
Public relations history is on a rising plane of research and publication. Borrowing from Soviet Premier Khrushchevâs 1956 comment that âHistorians are dangerous and capable of upsetting everythingâ, the commentary argues that it needs to be more challenging, more critical, and seeking other voices. There is a strengthening debate over public relationsâ historiography which needs to extend to all countries and types of public relations practice and theory
An exploratory qualitative study of values issues associated with training and practice in pluralistic counselling
Background: A pluralistic model of practice has become increasingly influential in recent years. A distinctive feature of this approach is its explicit grounding within a philosophical and moral perspective.Aim: The aim of this study was to investigate issues and challenges that pluralistic counsellors experience in relation to values dilemmas that arise in practice.Methodology: Twelve practitioners, of various experience levels, who identified as pluralistic counsellors, were invited to take part in semi-structured interviews. Transcripts were analysed using a method of thematic analysis.Findings: Participants viewed their personal values to be compatible with the values that they perceived pluralistic counselling to hold, and reported that they chose pluralism as a modality because they found a similarity between their personal values and the values of pluralistic counselling. Core values associated with pluralistic practice included the following: the importance of connection, âthere is no one right way to beâ, equality (not taking an expert role), honesty, and willingness to make use of research evidence. Participants also described value dilemmas, and their use of supervision in dealing with value issues.Implications: The implications of these findings for training, research and practice are discussed
Antelope (woman) and buffalo (woman) : Contemporary literary transformations of a topos in Yoruba culture.
This thesis explores four contemporary literary transformations of the topos of agbonrin and efon, antelope (woman) and buffalo (woman) respectively, in D.O. Fagunwa's Ogboju Ode Ninu Igbo Irunmale and Igbo Olodumare, Amos Tutuola's My Life in the Bush of Ghosts, Mobolaji Adenubi's "The Importance of Being Prudent", and Ben Okri's three abiku narratives. The Famished Road, Songs of Enchantment, and Infinite Riches. The introductory chapter raises theoretical issues regarding the notion of a topos itself and examines how these resonate with central Yoruba concepts. Furthermore, it provides an overview of Yoruba cultural beliefs associated with the figures of antelope (woman) and buffalo (woman) and comments on contemporary literary transformations of this topos in general. Each of the consecutive chapters represents an in-depth analysis and interpretation of one contemporary author's literary transformation of the topos of antelope (woman) and/or buffalo (woman). By putting each writer's deployment of the motif of agbonrin and efon in a biographical, historical and socio-cultural perspective, I explore how he or she - more or less consciously - invests it with new meanings and, in the process, transforms it, and how the topos of antelope (woman) and buffalo (woman) thus comes to serve manifold symbolic or metaphoric purposes, reflecting on and expressing a whole range of issues. Not only is the topos as such continuous beyond the precolonial period but it also assumes a new relevance with respect to the socio-cultural and political anxieties generated in the colonial and post-colonial climates. The contemporary literary transformations explored in this thesis all mediate and negotiate personal, socio-cultural and political anxieties in the wake of sustained contact with the West, especially through Christian missionary activity and colonialism. The thematisation of gender relations plays an important symbolic, metaphoric and metonymic role in this respect, since the way in which each writer's literary transformation of the motif of agbonrin and efon relates to the issue of women and female agency in Yoruba culture, or, more generally, in Nigerian culture, is an important means of communicating and conceptualising change
Properties of Groove Chambers
Groove chambers with different pitch and gap height have been tested. Gas
amplifications of the order of a few times 10 have been obtained.
Combining a groove structure with a GEM pre-amplification foil a gas gain of
10 was reached. The device is robust and can be produced at low cost in
large sizes by a laser technique
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