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1.
Rev Sci Instrum ; 88(8): 083103, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28863676

RESUMO

We have developed a charge-coupled device (CCD) with 5 µm × 45 µm pixels on high-resistivity silicon. The fully depleted 200 µm-thick silicon detector is back-illuminated through a 10 nm-thick in situ doped polysilicon window and is thus highly efficient for soft through >8 keV hard X-rays. The device described here is a 1.5 megapixel CCD with 2496 × 620 pixels. The pixel and camera geometry was optimized for Resonant Inelastic X-ray Scattering (RIXS) and is particularly advantageous for spectrometers with limited arm lengths. In this article, we describe the device architecture, construction and operation, and its performance during tests at the Advance Light Source (ALS) 8.0.1 RIXS beamline. The improved spectroscopic performance, when compared with a current standard commercial camera, is demonstrated with a ∼280 eV (CK) X-ray beam on a graphite sample. Readout noise is typically 3-6 electrons and the point spread function for soft CK X-rays in the 5 µm direction is 4.0 µm ± 0.2 µm. The measured quantum efficiency of the CCD is greater than 75% in the range from 200 eV to 1 keV.

2.
Rev Sci Instrum ; 88(5): 056105, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28571430

RESUMO

Tagging of neutrons (2.45 MeV) with their associated 3He particles from deuterium-deuterium (D-D) fusion reactions has been demonstrated in a compact neutron generator setup enabled by a high brightness, microwave-driven ion source with a high fraction of deuterons. Energy spectra with well separated peaks of the D-D fusion reaction products, 3He, tritons, and protons, were measured with a silicon PIN diode. The neutrons were detected using a liquid scintillator detector with pulse shape discrimination. By correlating the 3He detection events with the neutron detection in time, we demonstrated the tagging of emitted neutrons with 3He particles detected with a Si PIN diode detector mounted inside the neutron generator vacuum vessel.

3.
Sci Total Environ ; 360(1-3): 223-32, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16316676

RESUMO

The Urban Regeneration and the Environment Research Programme (URGENT) required a system for cataloguing its datasets and enabling its scientific community to discover what data were available to it. This community was multidisciplinary in nature and therefore needed a range of facilities for searching. Of particular importance were facilities to help those unfamiliar with specialist terminology. To meet these needs, four applications were designed and developed: a Metadata Capture Tool for describing datasets in compliance with the National Geospatial Data Framework (NGDF) standard, a Term Entry Tool for creating an ISO compliant thesaurus, a Thesaurus Builder for merging thesauri and a Search Tool. To encourage users to help in cataloguing data, the capture tools were written as stand alone applications, which users could keep and use to build their own metadatabases. The tools contained export and import facilities that allowed the URGENT Data Centre to build a central database and publish it upon the web. During the development work, it was found necessary to extend the NGDF standard as it could not adequately describe time variant or 3-D atmospheric datasets. The four applications met their design objectives. However, a number of ergonomic issues will need to be addressed if the system is to meet the needs of the much larger up coming programmes. The main challenges will be moving from the NGDF standard to the ISO standard, hence bringing the work into line with the recommendations of the INSPIRE Project, and merging the metadatabase with the scientific database, which enable metadata maintenance to be semi-automated.


Assuntos
Bases de Dados Factuais , Monitoramento Ambiental , Armazenamento e Recuperação da Informação/métodos , Catalogação , Bases de Dados Factuais/normas , Poluentes Ambientais , Internet , Reino Unido , Interface Usuário-Computador , Vocabulário Controlado
5.
Food Manage ; 26(7): 118-20, 122, 124 passim, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10112465

RESUMO

How are government controls affecting healthcare foodservices?Are growing elderly & outpatient populations changing foodservices' missions. What are the hottest trends? As members of the American Society for Hospital Food Service Administrators prepared for their annual meeting in Orlando, FM queried 11 Southeastern directors to learn their most pressing concerns & how they are positioning their departments for the future.


Assuntos
Serviço Hospitalar de Nutrição/tendências , Idoso , Fiscalização e Controle de Instalações/tendências , Administradores Hospitalares , Humanos , Garantia da Qualidade dos Cuidados de Saúde/tendências , Sudeste dos Estados Unidos
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