Evaluation of high specific-heat ceramic for regenerator use at temperatures between 2-30 K

Specific heat, thermal conductivity (both in the range 2-30 K), and microhardness data were measured on the ceramics labelled LS-8, LS-8A, and LS-8A doped with CsI, SnCl2, and AgCl. A work hardened sample of LS-8A was also studied in an effort to determine the feasibility of using these types of LS-8 materials to replace Pb spheres in the regenerator of the JPL cryocooler. The LS-8A materials are all more than an order of magnitude harder than Pb, and the dopants do not significantly improve the hardness. However, the SnCl2 dopant has a remarkable effect in improving the specific heat and thermal conductivity of LS-8A. The SnCl2 doping level which maximized the regenerator enthalpy change in going from an unloaded to a loaded condition was found to be 0.2 percent SnCl2 in LS-8A. It was also found that the enthalpy change for a regenerator employing the LS-8A material is more than three times larger than for the Pb spheres case. The use of rods, rather than spheres, of optimally doped LS-8A in regenerators is discussed

Face-to-face or distance training? Two different approaches to motivate SMEs to learn - an update

In the past, too many government-sponsored initiatives have presented learning resources that have been wasted because the target small business audience has failed to make use of them. This paper explores the issue of offering learning materials to small and medium-sized enterprises (SMEs) in a manner that recognizes their working environment, mode of operation and preferred learning methods. It then outlines methods currently being tested in the UK and Ireland, and indicates preliminary findings. The two methodologies are different in that the UK (LSSB - Learning Support for Small Businesses) programme is aimed at distance learning in primarily small businesses, whilst the Irish (University of Limerick and Limerick City Enterprise Board) programme is aimed at face-to-face learning primarily in micro-enterprises. Preliminary findings are presented

Attacks on midwives, attacks on women’s choices

Nadine Edwards, Jo Murphy-Lawless, Mavis Kirkham and Sarah Davies ask whether recent attacks on midwives are a Human Rights issu

Thallous halide materials for use in cryogenic applications

Thallous halides, either alone or in combination with other ceramic materials, are used in cryogenic applications such as heat exchange material for the regenerator section of a closed-cycle cryogenic refrigeration section, as stabilizing coatings for superconducting wires, and as dielectric insulating materials. The thallous halides possess unusually large specific heats at low temperatures, have large thermal conductivities, are nonmagnetic, and are nonconductors of electricity. They can be formed into a variety of shapes such as spheres, bars, rods, or the like and can be coated onto substrates

Lagoon livelihoods: gender and shell money in Langalanga, Solomon Islands

© 2018, The Author(s). Gender shapes livelihoods through access to resources and the distribution of benefits from economic activities. To work effectively with local people, resource management and community development initiatives should therefore be sensitive to the influence of gender on livelihoods. This paper considers gender in the context of broader social trends around livelihoods and focuses on a case study of shell money production and trade in the Langalanga Lagoon in Malaita Province, Solomon Islands. We pool data from several recent research projects with historical material from secondary sources. We find that the gender division of labour in the shell money value chain has changed somewhat over time, particularly in that women are now actively involved in trading. However, this shift has created friction due to norms about what kinds of activities are suitable for women, and who should control cash incomes. Whilst shell money remains one of the most important livelihoods in Langalanga lagoon, our findings also illustrate that the shell money value chain and the income earned varies considerably from family to family, with some making a better living than others. We argue that interventions seeking to improve livelihoods in coastal communities should thus be based on an understanding of differentiation within communities, and practitioners should consider whether interventions will result in community development, or may have the impact of increasing inequality between families

Celebrating the Year of Russia: To Russia with Love Choral Concert

KSU Chamber Singers, Men\u27s Ensemble, and University Chorale, under the direction of Dr. Leslie Blackwell, present To Russia wih Love in celebration of KSU\u27s Year of Russia.https://digitalcommons.kennesaw.edu/musicprograms/1913/thumbnail.jp

Optimal discrete stopping times for reliability growth tests

Often, the duration of a reliability growth development test is specified in advance and the decision to terminate or continue testing is conducted at discrete time intervals. These features are normally not captured by reliability growth models. This paper adapts a standard reliability growth model to determine the optimal time for which to plan to terminate testing. The underlying stochastic process is developed from an Order Statistic argument with Bayesian inference used to estimate the number of faults within the design and classical inference procedures used to assess the rate of fault detection. Inference procedures within this framework are explored where it is shown the Maximum Likelihood Estimators possess a small bias and converges to the Minimum Variance Unbiased Estimator after few tests for designs with moderate number of faults. It is shown that the Likelihood function can be bimodal when there is conflict between the observed rate of fault detection and the prior distribution describing the number of faults in the design. An illustrative example is provided

Local status and power in area-based health improvement partnerships

This is the authors' PDF version of an article published in Health© 2014. The definitive version is available at http://hea.sagepub.comArea-based initiatives (ABIs) have formed an important part of public policy towards more socio-economically deprived areas in many countries. Co-ordinating service provision within and across sectors has been a common feature of these initiatives. Despite sustained policy interest in ABIs, little empirical work has explored relations between ABI providers and partnership development within this context remains under-theorised. This paper addresses both of these gaps by exploring partnerships as a social and developmental process, drawing on concepts from figurational sociology to explain how provider relations develop within an ABI. Qualitative methods were used to explore, prospectively, the development of an ABI targeted at a town in the north west of England. A central finding was that, although effective delivery of ABIs is premised on a high level of coordination between service providers, the pattern of interdependencies between providers limits the frequency and effectiveness of cooperation. In particular, the interdependency of ABI providers with others in their organisation (what is termed here ‘organisational pull’) constrained the ways in which they worked with providers outside of their own organisations. ‘Local’ status, which could be earned over time, enabled some providers to exert greater control over the way in which provider relations developed during the course of the initiative. These findings demonstrate how historically constituted social networks, within which all providers are embedded, shape partnership development. The theoretical insight developed here suggests a need for more realistic expectations among policy makers about how and to what extent provider partnerships can be managed. Keywords: partnership, collaboration, community services, area-based initiatives, organisational pull, figurational sociologyNational Health Service (NHS

Oxidation mechanism in metal nanoclusters: Zn nanoclusters to ZnO hollow nanoclusters

Zn nanoclusters (NCs) are deposited by Low-energy cluster beam deposition technique. The mechanism of oxidation is studied by analysing their compositional and morphological evolution over a long span of time (three years) due to exposure to ambient atmosphere. It is concluded that the mechanism proceeds in two steps. In the first step, the shell of ZnO forms over Zn NCs rapidly up to certain limiting thickness: with in few days -- depending upon the size -- Zn NCs are converted to Zn-ZnO (core-shell), Zn-void-ZnO, or hollow ZnO type NCs. Bigger than ~15 nm become Zn-ZnO (core-shell) type: among them, NCs above ~25 nm could able to retain their initial geometrical shapes (namely triangular, hexagonal, rectangular and rhombohedral), but ~25 to 15 nm size NCs become irregular or distorted geometrical shapes. NCs between ~15 to 5 nm become Zn-void-ZnO type, and smaller than ~5 nm become ZnO hollow sphere type i.e. ZnO hollow NCs. In the second step, all Zn-void-ZnO and Zn-ZnO (core-shell) structures are converted to hollow ZnO NCs in a slow and gradual process, and the mechanism of conversion proceeds through expansion in size by incorporating ZnO monomers inside the shell. The observed oxidation behaviour of NCs is compared with theory of Cabrera - Mott on low-temperature oxidation of metal.Comment: 9 pages, 8 figure

Data assimilation with correlated observation errors: experiments with a 1-D shallow water model

Remote sensing observations often have correlated errors, but the correlations are typically ignored in data assimilation for numerical weather prediction. The assumption of zero correlations is often used with data thinning methods, resulting in a loss of information. As operational centres move towards higher-resolution forecasting, there is a requirement to retain data providing detail on appropriate scales. Thus an alternative approach to dealing with observation error correlations is needed. In this article, we consider several approaches to approximating observation error correlation matrices: diagonal approximations, eigendecomposition approximations and Markov matrices. These approximations are applied in incremental variational assimilation experiments with a 1-D shallow water model using synthetic observations. Our experiments quantify analysis accuracy in comparison with a reference or ‘truth’ trajectory, as well as with analyses using the ‘true’ observation error covariance matrix. We show that it is often better to include an approximate correlation structure in the observation error covariance matrix than to incorrectly assume error independence. Furthermore, by choosing a suitable matrix approximation, it is feasible and computationally cheap to include error correlation structure in a variational data assimilation algorithm