216 research outputs found

    The Preparation of Fine Particulate for Electron Microscopy Investigations Using Dental Amalgam

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    Samples of high Tc superconductors and metal powders have been prepared for Scanning and Transmission Electron Microscopy examination by a novel method. Dental amalgam, commonly used for filling cavities in teeth by dentists, has been used as a binding agent to hold the sample particulate together during sample preparation. The amalgam was pressed into a small rod 3 mmn in diameter and samples were prepared by cutting slices from the rod followed by mechanical grinding and ion milling to perforation. This technique is extremely easy and offers several advantages over other preparation methods. Experiments revealed difficulties due to preferential sputtering yield, but generally these could be overcome and good thermal and electrical properties of the amalgam partially offset the former inconveniences. It should be possible to use this technique for any number of materials, including ceramic materials and small non-spherical particulate

    Liquid metal extraction of Nd from NdFeB magnet scrap

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    This research involves using molten magnesium (Mg) to remove neodymium (Nd) from NdFeB magnet scrap by diffusion. Mg was melted over pieces of NdFeB scrap and held at temperatures in the range 675–705 Β°C for 2–8 h. The Mg was allowed to solidify, and the castings were then sectioned and characterized using scanning electron microscopy, x-ray diffraction, and chemical analysis. Nd was found to have diffused out of the solid scrap into the molten Mg. The thickness of the diffusion layer was measured, the diffusion of Nd through the NdFeB scrap into liquid Mg was described, and the diffusion coefficient of Nd in liquid Mg was estimated

    Synthesis and Processing of MgB2MgB_2 powders and wires

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    Sintered powders and wires of superconducting MgB2MgB_2 have been fabricated under a variety of conditions in order to determine details of the diffusion of the MgMg into BB and to study the types of defects that arise during growth. For samples prepared by exposure of boron to MgMg vapor at 950∘C950^{\circ}C, the conversion of particles of less than 100μm100\mu m size particles to MgB2MgB_2 is complete in about 2h2 h. The lattice parameters of the MgB2MgB_2 phase determined from X-ray are independent of the starting stoichiometry and the time of reaction. Wire segments of MgB2MgB_2 with very little porosity have been produced by reacting 141μm141 \mu m diameter boron fibers in an atmosphere of excess MgMg vapor at 950∘C950^{\circ}C. Defects in the reacted fibers are predominantly the voids left as the boron is converted to MgB2MgB_2

    ΠœΠ°Ρ‚Π΅ΠΌΠ°Ρ‚ΠΈΡ‡Π΅ΡΠΊΠΎΠ΅ ΠΌΠΎΠ΄Π΅Π»ΠΈΡ€ΠΎΠ²Π°Π½ΠΈΠ΅ Π³ΠΈΠ΄Ρ€ΠΎΠ³Π°Π·ΠΎΠ΄ΠΈΠ½Π°ΠΌΠΈΠΊΠΈ ΠΈ тСпломассопСрСноса Π² сдвиговых тСчСниях рСологичСски слоТных вязких срСд: ΠΈΠ΄Π΅ΠΈ, Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚Ρ‹, пСрспСктивы ΠΏΡ€ΠΎΠ³Π½ΠΎΠ·Π° процСссов

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    Π’ настоящСй Ρ€Π°Π±ΠΎΡ‚Π΅ прСдставлСн критичСский Π°Π½Π°Π»ΠΈΠ· ΠΏΡ€ΠΎΠ±Π»Π΅ΠΌ, Ρ€Π΅Π·ΡƒΠ»ΡŒΡ‚Π°Ρ‚ΠΎΠ² ΠΈ пСрспСктив исслСдований Ρ‚Π΅Ρ‡Π΅Π½ΠΈΠΉ слоТных ΠΏΠΎ структурС/Ρ€Π΅ΠΎΠ»ΠΎΠ³ΠΈΠΈ вязких срСд Π² Ρ‚Ρ€ΡƒΠ±ΠΎΠΏΡ€ΠΎΠ²ΠΎΠ΄Π½Ρ‹Ρ… систСмах (ΡƒΠ·Π»Π°Ρ… оборудования Π½Π΅Ρ„Ρ‚Π΅Π³Π°Π·ΠΎΠ²ΠΎΠΉ, Ρ…ΠΈΠΌΠΈΠΊΠΎ-тСхнологичСской ΠΈ Ρ‚Π΅ΠΏΠ»ΠΎ-энСргСтичСской ΠΏΡ€ΠΎΠΌΡ‹ΡˆΠ»Π΅Π½Π½ΠΎΡΡ‚ΠΈ), ΠΈΡΠΏΡ‹Ρ‚Ρ‹Π²Π°ΡŽΡ‰ΠΈΡ… Π½Π° сСбС влияниС нСизотСрмичности, нСстационарности, пСрСмСнности Ρ‚Π΅ΠΏΠ»ΠΎ- ΠΈ рСофизичСских свойств, Π²Π½Π΅ΡˆΠ½ΠΈΡ… ΠΏΠΎΠ»Π΅ΠΉ ΠΎΡ‚ дСйствия ΠΈΠ½Π΅Ρ€Ρ†ΠΈΠΎΠ½Π½Ρ‹Ρ… ΠΈ Π³Ρ€Π°Π²ΠΈΡ‚Π°Ρ†ΠΈΠΎΠ½Π½Ρ‹Ρ… сил, особСнностСй Ρ„ΠΎΡ€ΠΌΡ‹ ΠΏΠΎΠΏΠ΅Ρ€Π΅Ρ‡Π½ΠΎΠ³ΠΎ сСчСния ΠΏΡ€ΠΎΡ‚ΠΎΡ‡Π½ΠΎΠΉ части. ОсобоС Π²Π½ΠΈΠΌΠ°Π½ΠΈΠ΅ удСляСтся: тСхнологиям модСлирования ΡƒΠ³Π»Π΅Π²ΠΎΠ΄ΠΎΡ€ΠΎΠ΄ΠΎΠ² (тяТСлых Π½Π΅Ρ„Ρ‚Π΅ΠΉ, масСл) ΠΏΡ€ΠΈ ΠΈΡ… транспортировкС Π½Π° участках Ρ‚Ρ€ΡƒΠ±/ΠΊΠ°Π½Π°Π»ΠΎΠ² с интСнсивным тСпломассообмСном; ΠΎΠΏΡ€Π΅Π΄Π΅Π»Π΅Π½ΠΈΡŽ ΠΌΠ΅Ρ€ ΠΏΠΎΠ²Ρ‹ΡˆΠ΅Π½ΠΈΡ энСргоэффСктивности ΠΈ ΡΡ‚Π°Π±ΠΈΠ»ΡŒΠ½ΠΎΡΡ‚ΠΈ функционирования оборудования, ΠΈΠ·ΡƒΡ‡Π΅Π½ΠΈΡŽ ΠΎΠΏΡ‹Ρ‚Π° Π°Π½Π°Π»ΠΈΠ·Π° ΠΏΡ€ΠΎΠ±Π»Π΅ΠΌ ΠΊΠΎΡ€Ρ€ΠΎΠ·ΠΈΠΈ энСргонапряТСнных элСмСнтов, Π° Ρ‚Π°ΠΊΠΆΠ΅ ΠΈΡ… очистки ΠΎΡ‚ загрязнСний

    Mode structure and ray dynamics of a parabolic dome microcavity

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    We consider the wave and ray dynamics of the electromagnetic field in a parabolic dome microcavity. The structure of the fundamental s-wave involves a main lobe in which the electromagnetic field is confined around the focal point in an effective volume of the order of a cubic wavelength, while the modes with finite angular momentum have a structure that avoids the focal area and have correspondingly larger effective volume. The ray dynamics indicates that the fundamental s-wave is robust with respect to small geometrical deformations of the cavity, while the higher order modes are associated with ray chaos and short-lived. We discuss the incidence of these results on the modification of the spontaneous emission dynamics of an emitter placed in such a parabolic dome microcavity.Comment: 50 pages, 17 figure

    The Economic Resource Receipt of New Mothers

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    U.S. federal policies do not provide a universal social safety net of economic support for women during pregnancy or the immediate postpartum period but assume that employment and/or marriage will protect families from poverty. Yet even mothers with considerable human and marital capital may experience disruptions in employment, earnings, and family socioeconomic status postbirth. We use the National Survey of Families and Households to examine the economic resources that mothers with children ages 2 and younger receive postbirth, including employment, spouses, extended family and social network support, and public assistance. Results show that many new mothers receive resources postbirth. Marriage or postbirth employment does not protect new mothers and their families from poverty, but education, race, and the receipt of economic supports from social networks do

    Development and validation of a questionnaire to measure moral distress in community pharmacists

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    The Author(s) 2016. . This article is published with open access at Springerlink.com This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. Jayne L. Astbury, and Cathal T. Gallagher, 'Development and validation of a questionnaire to measure moral distress in community pharmacists', International Journal of Clinical Pharmacy (2017) Vol 39(1): 156-164, first published online on 22 December 2016, the version of record is available on line via doi: 10.1007/s11096-016-0413-3 Funding for this work was provided by Pharmacy Research UK (PRUK).Background Pharmacists work within a highly-regulated occupational sphere, and are bound by strict legal frameworks and codes of professional conduct. This regulatory environment creates the potential for moral distress to occur due to the limitations it places on acting in congruence with moral judgements. Very little research regarding this phenomenon has been undertaken in pharmacy: thus, prominent research gaps have arisen for the development of a robust tool to measure and quantify moral distress experienced in the profession. Objective The aim of this study was to develop an instrument to measure moral distress in community pharmacists. Setting Community pharmacies in the United Kingdom. Method This study adopted a three-phase exploratory sequential mixed-method design. Three semi-structured focus groups were then conducted to allow pharmacists to identify and explore scenarios that cause moral distress. Each of the identified scenarios were developed into a statement, which was paired with twin seven-point Likert scales to measure the frequency and intensity of the distress, respectively. Content validity, reliability, and construct validity were all tested, and the questionnaire was refined. Main outcome measure The successful development of the valid instrument for use in the United Kingdom. Results This research has led to the development of a valid and reliable instrument to measure moral distress in community pharmacists in the UK. The questionnaire has already been distributed to a large sample of community pharmacists. Conclusion Results from this distribution will be used to inform the formulation of coping strategies for dealing with moral distress.Peer reviewedFinal Published versio
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