The Role of Final State Interactions in Quasielastic 56^{56}Fe(e,e′)(e,e') Reactions at large ∣q⃗∣|\vec q|

A relativistic finite nucleus calculation using a Dirac optical potential is used to investigate the importance of final state interactions [FSI] at large momentum transfers in inclusive quasielastic electronuclear reactions. The optical potential is derived from first-order multiple scattering theory and then is used to calculate the FSI in a nonspectral Green's function doorway approach. At intermediate momentum transfers excellent predictions of the quasielastic $^{56}$Fe$(e,e')$ experimental data for the longitudinal response function are obtained. In comparisons with recent measurements at $|{\vec q|}=1.14$~GeV/c the theoretical calculations of $R_L$ give good agreement for the quasielastic peak shape and amplitude, but place the position of the peak at an energy transfer of about $40$~MeV higher than the data.Comment: 13 pages typeset using revtex 3.0 with 6 postscript figures in accompanying uuencoded file; submitted to Phys. Rev.

Hawaiian Plumerias

Reprint June 1972The plumeria is an important ornamental tree in Hawaii as well as in Florida, the West Indies, Central America, India, China, Indonesia, Australia, islands of the Pacific basin, and some other tropical regions. This booklet covers all aspects of plumeria cultivation in Hawaii

Towards the GEOSAT Follow-On Precise Orbit Determination Goals of High Accuracy and Near-Real-Time Processing

The US Navy's GEOSAT Follow-On spacecraft (GFO) primary mission objective is to map the oceans using a radar altimeter. Satellite laser ranging data, especially in combination with altimeter crossover data, offer the only means of determining high-quality precise orbits. Two tuned gravity models, PGS7727 and PGS7777b, were created at NASA GSFC for GFO that reduce the predicted radial orbit through degree 70 to 13.7 and 10.0 mm. A macromodel was developed to model the nonconservative forces and the SLR spacecraft measurement offset was adjusted to remove a mean bias. Using these improved models, satellite-ranging data, altimeter crossover data, and Doppler data are used to compute both daily medium precision orbits with a latency of less than 24 hours. Final precise orbits are also computed using these tracking data and exported with a latency of three to four weeks to NOAA for use on the GFO Geophysical Data Records (GDR s). The estimated orbit precision of the daily orbits is between 10 and 20 cm, whereas the precise orbits have a precision of 5 cm

Application of Multiple Scattering Theory to Lower Energy Elastic Nucleon-Nucleus Reactions

The optical model potentials for nucleon-nucleus elastic scattering at $65$~MeV are calculated for $^{12}$C, $^{16}$O, $^{28}$Si, $^{40}$Ca, $^{56}$Fe, $^{90}$Zr and $^{208}$Pb in first order multiple scattering theory, following the prescription of the spectator expansion, where the only inputs are the free NN potentials, the nuclear densities and the nuclear mean field as derived from microscopic nuclear structure calculations. These potentials are used to predict differential cross sections, analyzing powers and spin rotation functions for neutron and proton scattering at 65 MeV projectile energy and compared with available experimental data.Comment: 12 pages (Revtex 3.0), 7 fig

Improved Refractories for IGCC Power Systems

The gasification of coal, petroleum residuals, and biomass provides the opportunity to produce energy more efficiently, and with significantly less environmental impact, than more-conventional combustion-based processes. In addition, the synthesis gas that is the product of the gasification process offers the gasifier operator the option of ''polygeneration'', i.e., the production of alternative products instead of power should it be economically favorable to do so. Because of these advantages, gasification is a key element in the U.S. Department of Energy?s Vision 21 power system. However, issues with both the reliability and the economics of gasifier operation will have to be resolved before gasification will be widely adopted by the power industry. Central to both increased reliability and economics is the development of materials with longer service lives in gasifier systems that can provide extended periods of continuous gasifier operation. The focus of the Advanced Refractories for Gasification project at the Albany Research Center is to develop improved materials capable of withstanding the harsh, high-temperature environment created by the gasification reaction, and includes both the refractory lining that insulates the slagging gasifier, as well as the thermocouple assemblies that are utilized to monitor gasifier operating temperatures. Current generation refractory liners in slagging gasifiers are typically replaced every 10 to 18 months, at costs ranging up to $2,000,000. Compounding materials and installation costs are the lost-opportunity costs for the three to four weeks that the gasifier is off-line for the refractory exchange. Current generation thermocouple devices rarely survive the gasifier start-up process, leaving the operator with no real means of temperature measurement during gasifier operation. As a result, the goals of this project include the development of a refractory liner with a service life at least double that of current generation refractory materials, and the design of a thermocouple protection system that will allow accurate temperature monitoring for extended periods of time

New developments in gasifier refractories

For Integrated Gasification Combined Cycle (IGCC) systems, operational reliability depends in part upon the ability of the materials of construction to tolerate harsh, high-temperature environments for extended periods of time. The harshest conditions within an IGCC system occur inside the gasifier itself, where for slagging systems the environment includes elevated temperature and pressure, as well as the presence of corrosive slags and gases. Attempts to enhance gasifier performance by operating at higher temperatures, with higher throughputs, and/or with variable feedstocks, put additional stress on the materials exposed to the operating environment, often resulting in a corresponding decrease in their useful service life. Current generation refractory materials commonly used at the hot face of commercial slagging systems will typically last from four to 18 months, depending on the operating conditions of the specific gasifier. However, as gasification technology matures, the need for new and improved materials will increase as the time between required maintenance shutdowns, and hence the economics and reliability of operation, are defined more and more by the service life of the materials from which the system is built. To address this need for materials development, the U.S. Department of Energy's Office of Fossil Energy and the Albany Research Center are exploring ways to extend the service life of the refractory liner that contains the gasification reaction in slagging gasifiers. In this paper, we examine how refractory materials fail in the gasifier environment, and introduce a new refractory designed specifically to resist such failures. Based on laboratory exposure tests, this new refractory is predicted to significantly enhance gasifier reliability and availability through increased service life

A qualitative study of stakeholders' perspectives on the social network service environment

Over two billion people are using the Internet at present, assisted by the mediating activities of software agents which deal with the diversity and complexity of information. There are, however, ethical issues due to the monitoring-and-surveillance, data mining and autonomous nature of software agents. Considering the context, this study aims to comprehend stakeholders' perspectives on the social network service environment in order to identify the main considerations for the design of software agents in social network services in the near future. Twenty-one stakeholders, belonging to three key stakeholder groups, were recruited using a purposive sampling strategy for unstandardised semi-structured e-mail interviews. The interview data were analysed using a qualitative content analysis method. It was possible to identify three main considerations for the design of software agents in social network services, which were classified into the following categories: comprehensive understanding of users' perception of privacy, user type recognition algorithms for software agent development and existing software agents enhancement

Sensitivities of the Proton-Nucleus Elastical Scattering Observables of 6He and 8He at Intermediate Energies

We investigate the use of proton-nucleus elastic scattering experiments using secondary beams of 6He and 8He to determine the physical structure of these nuclei. The sensitivity of these experiments to nuclear structure is examined by using four different nuclear structure models with different spatial features using a full-folding optical potential model. The results show that elastic scattering at intermediate energies (<100 MeV per nucleon) is not a good constraint to be used to determine features of structure. Therefore researchers should look elsewhere to put constraints on the ground state wave function of the 6He and 8He nuclei.Comment: To be published in Phys. Rev.

Changes in body weight and food choice in those attempting smoking cessation: a cluster randomised controlled trial

&lt;p&gt;&lt;b&gt;Background:&lt;/b&gt; Fear of weight gain is a barrier to smoking cessation and significant cause of relapse for many people. The provision of nutritional advice as part of a smoking cessation programme may assist some in smoking cessation and perhaps limit weight gain. The aim of this study was to determine the effect of a structured programme of dietary advice on weight change and food choice, in adults attempting smoking cessation.&lt;/p&gt; &lt;p&gt;&lt;b&gt;Methods:&lt;/b&gt; Cluster randomised controlled design. Classes randomised to intervention commenced a 24-week intervention, focussed on improving food choice and minimising weight gain. Classes randomised to control received "usual care".&lt;/p&gt; &lt;p&gt;&lt;b&gt;Results:&lt;/b&gt; Twenty-seven classes in Greater Glasgow were randomised between January and August 2008. Analysis, including those who continued to smoke, showed that actual weight gain and percentage weight gain was similar in both groups. Examination of data for those successful at giving up smoking showed greater mean weight gain in intervention subjects (3.9 (SD 3.1) vs. 2.7 (SD 3.7) kg). Between group differences were not significant (p=0.23, 95% CI -0.9 to 3.5). In comparison to baseline improved consumption of fruit and vegetables and breakfast cereal were reported in the intervention group. A higher percentage of control participants continued smoking (74% vs. 66%).&lt;/p&gt; &lt;p&gt;&lt;b&gt;Conclusions:&lt;/b&gt; The intervention was not successful at minimising weight gain in comparison to control but was successful in facilitating some sustained improvements in the dietary habits of intervention participants. Improved quit rates in the intervention group suggest that continued contact with advisors may have reduced anxieties regarding weight gain and encouraged cessation despite weight gain. Research should continue in this area as evidence suggests that the negative effects of obesity could outweigh the health benefits achieved through reductions in smoking prevalence.&lt;/p&gt