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91.
Friha Khelfaoui Mohammed Ameri Djillali Bensaid Ibrahim Ameri Yarub Al-Douri 《Journal of Superconductivity and Novel Magnetism》2018,31(10):3183-3192
Structural, elastic, thermodynamic, electronic, and magnetic properties of the full-Heusler compound Ag2CeAl were determined using generalized gradient approximation with exchange-correlation functional GGA (PBEsol) with spin-orbit coupling (SOC) correction. The elastic modulus and their pressure dependence are calculated. From the elastic parameter behavior, it is inferred that this compound is elastically stable and ductile in nature. Through the quasi-harmonic Debye model, in which the phononic effect is considered the effect of pressure P (0 to 50) and temperature T (0 to 1000) on the lattice constant, the elastic parameters, bulk modulus B, heat capacity and thermal expansion α, internal energy U, entropy S, Debye temperature ??D, Helmholtz free energy A, and Gibbs free energy G are investigated. The thermodynamic properties show that the compound Ag2CeAl is a heavy fermion material. The density of state (DOS), magnetic momentum, and band structure are computed, to investigate the magnetic and metallic characteristics. The calculated polarization of the compound is 77.34%. The obtained results are the first predictions of the physical properties for the rare-earth-based (Ce) full-Heusler Ag2CeAl. 相似文献
92.
Mahoney PM Hurst PR McLeod BJ McConnell MA Thompson EG 《Reproduction (Cambridge, England)》2003,125(5):733-741
Mast cell populations in the vaginal cul-de-sac of female brushtail possums do not appear to be related to microbial invasion but changes in their density occur at oestrus, indicating a hormonal influence. The present study examined the effect of treatment with oestradiol on microflora and on mast cell numbers and their spatial location in cul-de-sac tissue of seasonally anoestrous brushtail possums. Tissue was collected from seasonally anoestrous brushtail possums (n = 6 per group) that were either untreated (anoestrous group) or were subjected to 6 days of treatment with oestradiol (oestradiol group) administered via subcutaneous implants or with the oil vehicle alone (control group). Tissue was collected aseptically for microbiological procedures and the fractionator and optical disector were used to quantify mast cell populations. Microflora populations were low (< 4.0 x 10(4) organisms g(-1)) and numbers of mast cells were similar in all groups. Mast cell density was greatest in epithelial and connective tissues from seasonally anoestrous and control animals and lowest in oestradiol-treated possums, in which there was a significant increase in cul-de-sac mass and volume. There is an inverse relationship between circulating oestrogen concentrations and mast cell density in possum cul-de-sac tissue, which is probably the result of an increase in tissue volume. 相似文献
93.
Slag samples, hot‐metal samples and hot‐metal temperatures were obtained during tapping of two blast furnaces. Sampling was carried out at different time points during tapping of three separate heats. The size distribution and composition of metal droplets found in the slag were determined using scanning electron microscopy. Only metal droplets above 0.75 μm could be counted and analysed. All droplets were below 8 μm in diameter and the great majority of these droplets were found to be between 0.75 and 2 μm. The size distribution did not differ significantly for different slag samples. Iron was the main droplet component. Electron probe microanalysis showed that the droplets contained small amounts of carbon. The percentage of the area in a studied cross‐section that was covered with metal droplets varied between 0.01 and 0.07%. Calculations based on Stoke's law showed that the distance droplets travel in the slag is in the micron range. Slag samples taken in the beginning of slag tapping contained more droplets than those taken in the middle of slag tapping, an indication that most droplets can be found in the area near the furnace wall. Some droplets were determined to have magnesium enrichment at the external surface. 相似文献
94.
Kingree J. B.; Simpson Alpha; Thompson Martie; McCrady Barbara; Tonigan J. Scott; Lautenschlager Gary 《Canadian Metallurgical Quarterly》2006,20(4):453
This article presents 5 studies related to the development and initial evaluation of the Survey of Readiness for Alcoholics Anonymous Participation (SYRAAP). The SYRAAP is a brief, multidimensional, self-administered instrument that assesses beliefs associated with Alcoholics Anonymous (AA) participation. Study 1 generated 239 candidate items for potential inclusion in the instrument. Study 2 assessed the content validity of these items according to 3 criteria and identified a subset of 60 with the highest values on the criteria for further consideration. Study 3 produced a shorter version of the SYRAAP and evaluated its structure, internal reliability, and validity. Study 4 reevaluated the structure and internal reliability of the SYRAAP and yielded findings that were generally consistent with those from Study 3. Study 5 established stability reliability for the instrument. The collective findings indicated the SYRAAP can reliably and validly assess individual-level beliefs associated with AA participation. The potential use of the SYRAAP for researchers and clinicians, along with limitations of the work presented here, are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Microstructural changes during ageing of Cu-2.5 wt% Ti 总被引:2,自引:0,他引:2
Microstructural changes in Cu-2.5wt % Ti during ageing at 573 and 773 K have been studied by transmission electron microscopy. Ageing times ranged from 60 sec to 200 h. Ordering of the precipitates was observed after very short ageing treatments at 773 K, and coarsening according tot
1/3 was also observed from very early times. The particles were observed to become increasingly aligned into rod-like groups along 10 0 as ageing progressed. These results permit a new interpretation of the strengthening mechanisms in this alloy. 相似文献
96.
97.
This paper argues that the combination of software agents with existing workflow management systems can facilitate the degree of co-ordination and collaboration required to make virtual enterprises a reality. It describes the use of software agents in the setting-up of decentralised workflows, the reactive and proactive redistribution of work during process failures, the promotion of interoperability between workflow management systems, and the visualisation and monitoring of decentralised business processes.An implementation is described which uses a number of industry standard components, such as the agent communication language defined by the Foundation for Intelligent Physical Agents, the Common Object Request Broker Architecture, Java and the Process Interchange Format. 相似文献
98.
99.
CJ Lacey HS Thompson EF Monteiro T O'Neill ML Davies FP Holding RE Fallon JS Roberts 《Canadian Metallurgical Quarterly》1999,179(3):612-618
A fusion protein vaccine consisting of human papillomavirus 6 L2E7 with Alhydrogel was developed for the treatment of genital warts. Twenty-seven subjects with genital warts received 3 immunizations over 4 weeks in an open-label study. The vaccine was well-tolerated, and all subjects made serum IgG antibodies, predominantly IgG1, against L2E7. Nineteen of 25 tested persons made antigen-specific T cell proliferative responses to L2E7, and peripheral blood mononuclear cells when cultured with L2E7 in vitro produced both interferon-gamma and interleukin (IL)-5, although IL-5 predominated after the final vaccination. Five subjects completely cleared warts within 8 weeks. Subjects whose warts were not cleared by 8 weeks were offered conventional therapy. Recurrence of warts was not seen in any of the 13 persons whose warts cleared by vaccine alone or with conventional therapy. While these preliminary results of the use of this therapeutic immunogen are encouraging, proof of efficacy will require randomized double-blind trials. 相似文献
100.
Jennings J. Richard; Maricq Hildegard R.; Canner Joseph; Thompson Bruce; Freedman Robert R.; Wise Robert; Kaufmann Peter G. 《Canadian Metallurgical Quarterly》1999,18(4):421
This study tested the reliability and validity of a diagnostic thermal vascular test (TVT) for patients with Raynaud's Phenomenon (RP). The TVT examined digital blood pressure responses to combined cooling and occlusion and was developed as part of the Raynaud's Treatment Study, a multicenter clinical trial comparing the efficacy of biofeedback and pharmacological treatment. A computerized system permitted efficient, accurate, and uniform testing at different geographical sites. A comparison of 199 patients with RP and 52 healthy controls is reported. The TVT showed a sensitivity of 79% and a specificity of 88%. Test–retest reliability was acceptable (r?=?.80). Addition of a psychological challenge failed to improve the discrimination between patients with RP and controls. The TVT separated patients with RP and controls as well as or better than existing tests and did so with enhanced ease of operation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献