The Experts below are selected from a list of 84 Experts worldwide ranked by ideXlab platform
Gus Hancock - One of the best experts on this subject based on the ideXlab platform.
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aligned N D , N S and O P atoms
1998Co-Authors: David H. Parker, Matthew L. Costen, Gus HancockAbstract:Velocity map imaging is used to characterise the angular distributions of atoms which are formed from the sequential two photon excitation of NO via the A 2 S q state. Molecules excited at 226 nm and dissociated at 339 nm from the same laser 3 . 2 . 4 . Source Yield two sets of products, ground state O P atoms in conjunction with N D and N S. The angular distributions are found to be well described by b parameters. The use of this method as a Source of monoenergetic aligned atoms for studies of reaction dynamics is discussed. q 1998 Elsevier Science B.V.
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The sequential two photon dissociation of NO as a Source of aligned N(2D), N(4S) and O(3P) atoms
Chemical Physics Letters, 1998Co-Authors: Bernard L. G. Bakker, André T. J. B. Eppink, David H. Parker, Matthew L. Costen, Gus Hancock, Grant A. D. RitchieAbstract:Abstract Velocity map imaging is used to characterise the angular distributions of atoms which are formed from the sequential two photon excitation of NO via the A 2 Σ + state. Molecules excited at 226 nm and dissociated at 339 nm from the same laser Source Yield two sets of products, ground state O( 3 P) atoms in conjunction with N( 2 D) and N( 4 S). The angular distributions are found to be well described by β parameters. The use of this method as a Source of monoenergetic aligned atoms for studies of reaction dynamics is discussed.
Ralph M. Carney - One of the best experts on this subject based on the ideXlab platform.
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SSBI Source Yield: An Examination of Sources Contacted During the SSBI.
1996Co-Authors: Ralph M. CarneyAbstract:Abstract : To meet the requirements of Executive Order 12968 to develop a common set of investigative standards for background investigations for access to classified information, the Personnel Security Committee (PSC) of the Security Policy Board (SPB) commissioned a study of the Sources contacted during the Single Scope Background Investigation (SSBI). A team of personnel security adjudicators reviewed 1,101 cases at four agencies which routinely conduct the SSBI: Central Intelligence Agency (CIA), Department of Defense (DoD), National Reconnaissance Office (NRO), and Office of Personnel Management (OPM). To ensure that the study examined only cases eligible for a full scope SSBI, case review focused on Subjects age 28 or older who had not received a prior investigation and who had issues in their background. Information was collected on the type of issue(s), the investigative Source(s) which provided information about the issue(s), and the minimum length of time required to develop the issue(s). In 81% of the cases the Subject, through the Personnel Security Questionnaire (PSQ) and the subject interview, provided the issue information. This means that only 19% of the cases were developed from Sources other than the Subject. The most productive standard interview Sources were Ex-Spouse, Relative, Employment, and Developed and Listed reference interviews. The most productive record Sources were Local Agency checks, Financial records and Employment records. Residence, Birth records (BVS), and Education records had very low productivity. The data indicated that 97.6% of all issue cases were developed within a 7-year scope. When the Subject did not disclose the issue, 86.6% of the issue information was captured within a 7-year scope.
Kimmo Saarinen - One of the best experts on this subject based on the ideXlab platform.
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Compact positron beam for measurement of transmission moderator efficiencies and positron Yields of encapsulated Sources
Applied Surface Science, 2006Co-Authors: Floris Reurings, A. Laakso, K. Rytsölä, A. Pelli, Kimmo SaarinenAbstract:Abstract We have constructed a simple positron beam for measuring both the efficiencies of positron moderator foils and the positron Yields of encapsulated positron beam Sources. The slow-positron emission rate from the moderator is determined from the positron annihilation radiation. This technique is also applied to measure Source Yields. In addition to the coincidence technique, the Source Yield is determined by measuring electric currents generated by the annihilating positrons. The performance of the system is demonstrated with different tungsten moderator foils before and after heat treatments, and several Na 22 Sources with primary activities in the range 1–50 mCi.
Brian Baetz - One of the best experts on this subject based on the ideXlab platform.
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Decision Support System for Rural Water Supply in the Nilgiris District of South India
Journal of Environmental Informatics, 2006Co-Authors: Daniel Olsen, Sarah E. Dickson, Brian BaetzAbstract:A considerable amount of knowledge exists for planning, designing, and implementing rural water supply schemes in developing countries around the world. Generalized decision support systems (DSSs) are used to tackle the daunting task of providing water in areas that have poor water reSources and limited financial capacity. However, there is a lack of site-specific DSSs that utilise local hydrological and socio-economic data for assessing regionally-based rural water supply schemes. In the Nilgiris District of South India, an organizational structure exists for improving local water reSources through watershed management projects, but many of the tools used to make informed decisions are ineffective, leading to poorly designed systems. Addressing this problem, a prototype DSS called Nilgiris Rural Water Supply (NRWS) was developed for rural water supply in the Nilgiris District. It assists planners in developing a decision-matrix for potential water Sources based on six criteria: water Source Yield; capital costs; cost and ease of operation and maintenance; impact of development; political/legal constraints; and water quality. Within the water Source Yield criterion, a simulation method was used to develop design specifications for the rainwater harvesting (RWH) Source. A general application of the rooftop RWH simulation was applied to ten villages throughout the Nilgiris District. One important discovery was that the village of Masinigudi, which lies in a rain shadow and receives the lowest level of annual rainfall in the district, performed to the same level as villages with a high annual rainfall. Since the region surrounding Masinigudi is deprived of water Sources, such as mountain streams and dug wells, RWH was found to be a feasible and economically viable solution.
A. Kreft - One of the best experts on this subject based on the ideXlab platform.
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Absolute determination of the neutron Source Yield using melamine as a neutron detector
Journal of Instrumentation, 2015Co-Authors: M. Ciechanowski, A. Bolewski, A. KreftAbstract:A new approach to absolute determination of the neutron Source Yield is presented. It bases on the application of melamine (C3H6N6) to neutron detection combined with Monte Carlo simulations of neutron transport. Melamine has the ability to detect neutrons via 14N(n, p)14C reaction and subsequent determination of 14C content. A cross section for this reaction is relatively high for thermal neutrons (1.827 b) and much lower for fast neutrons. A concentration of 14C nuclei created in the irradiated sample of melamine can be reliably measured with the aid of the accelerator mass spectrometry (AMS). The mass of melamine sufficient for this analysis is only 10 mg. Neutron detection is supported by Monte Carlo simulations of neutron transport carried out with the use of MCNP-4C code. These simulations are aimed at computing the probability of 14C creation in the melamine sample per the Source neutron. The result of AMS measurements together with results of MCNP calculations enable us to determine the number of neutrons emitted from the Source during the irradiation of melamine. The proposed method was applied for determining the neutron emission from a commercial 252Cf neutron Source which was independently calibrated. The measured neutron emission agreed with the certified one within uncertainty limits. The relative expanded uncertainty (k=2) of the absolute neutron Source Yield determination was estimated at 2.6%. Apart from calibration of radionuclide neutron Sources the proposed procedure could facilitate absolute Yield measurements for more complex Sources. Potential applications of this methodology as it is further developed include diagnostics of inertial confinement fusion and plasma-focus experiments, calibration of neutron measurement systems at tokamaks and accelerator-based neutron Sources as well as characterization of neutron fields generated in large particle detectors during collisions of hadron beams.