19 research outputs found

    Super Thin Ultra-Light Posttensioned Flat Plate Floor Systems for Affordable Urban Housing

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    The objective of this research is the development of super thin ultra-light post-tensioned flat plate floor systems by using high performing ultra-light cementitious composites that lead to slender, sustainable structures to remove the limitations imposed by commodity materials on mid- and high-rise construction. This objective will be achieved by investigating the full-scale behavior of these super thin floor systems using high fidelity finite element analyses in terms of flexure, punching shear, long term deflections, and vibrations

    Superconductivity in the Nb-Ru-Ge σ\sigma-Phase

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    We show that the previously unreported ternary σ\sigma-phase material Nb20.4_{20.4}Ru5.7_{5.7}Ge3.9_{3.9} is a superconductor with a critical temperature of 2.2 K. Temperature-dependent magnetic susceptibility, resistance, and specific heat measurements were used to characterize the superconducting transition. The Sommerfeld constant γ\gamma for Nb20.4_{20.4}Ru5.7_{5.7}Ge3.9_{3.9} is 91 mJ mol-f.u.1^{-1}K2^{-2} and the specific heat anomaly at the superconducting transition, Δ\DeltaC/γ\gammaTc_c, is approximately 1.38. The zero-temperature upper critical field (μ0\mu_0Hc2_{c2}(0)) was estimated to be 2 T by resistance data. Field-dependent magnetization data analysis estimated μ0\mu_0Hc1_{c1}(0) to be 5.5 mT. Thus, the characterization shows Nb20.4_{20.4}Ru5.7_{5.7}Ge3.9_{3.9} to be a type II BCS superconductor. This material appears to be the first reported ternary phase in the Nb-Ru-Ge system, and the fact that there are no previously reported binary Nb-Ru, Nb-Ge, or Ru-Ge σ\sigma-phases shows that all three elements are necessary to stabilize the material. A σ\sigma-phase in the Ta-Ru-Ge system was synthesized but did not display superconductivity above 1.7 K, which suggests that electron count cannot govern the superconductivity observed. Preliminary characterization of a possible superconducting σ\sigma-phase in the Nb-Ru-Ga system is also reported.Comment: 7 pages, 8 figures, 3 table

    Ternary Bismuthide SrPtBi2: Computation and Experiment in Synergism to Explore Solid-State Materials

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    A combination of theoretical calculation and the experimental synthesis to explore the new ternary compound is demonstrated in the Sr-Pt-Bi system. Since Pt-Bi is considered as a new critical charge-transfer pair for superconductivity, it inspired us to investigate the Sr-Pt-Bi system. With a thorough calculation of all the known stable/metastable compounds in the Sr-Pt-Bi system and crystal structure predictions, the thermodynamic stability of hypothetical stoichiometry, SrPtBi2, is determined. Followed by the high-temperature synthesis and crystallographic analysis, the first ternary bismuthide in Sr-Pt-Bi, SrPtBi2 was prepared and the stoichiometry was confirmed experimentally. SrPtBi2 crystallizes in the space group Pnma (S.G. 62, Pearson Symbol oP48), which matches well with theoretical prediction using an adaptive genetic algorithm (AGA). Using first-principles calculations, we demonstrate that the orthorhombic structure has lower formation energies than other 112 structure types, such as tetragonal BaMnBi2 (CuSmP2) and LaAuBi2 (CuHfSi2) structure types. The bonding analysis indicates the Pt-Bi interactions play a critical role in structural stability. The physical properties measurements show the metallic properties with low electron-phonon interactions at the low temperature, which agrees with the electronic structure assessment.Comment: 12 pages, 7 figure

    The assessment of selected factors influencing intent to get pregnant in the Greater Poland Region

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    introduction and objective. Nowadays, people decide to have a baby by first analysing their financial situation. Tradition is no longer a factor which determines the decision whether or not to have a baby. A prognosis of the Polish Central Statistical Office (GUS) shows that the population of Poland will fall from 38 to 36 million by 2035. The aim of this study is to assess the procreation behaviour of women in Greater Poland Region. materials and methods. For the research purpose, 3,120 women of reproductive age were examined by using an author designed questionnaire and a synthetic Family Financial Standard Index. results: 74.6% of the respondents lived in an urban area, 25.4% of women come from a rural area. 49% of examined women did not want to have a bigger family, 45% would like to have another child. Analysis of the reasons why women did not want to have another baby revealed that predominance of the financial factor – 67%, living conditions – 18.4% and health– 13.2%. Only 11.9% of the women declared their high financial status, 4.8% of families received family allowance from the government; 88.4% of the examined families did not receive any social benefits. Bad housing situation was declared by 5% of the respondents, 26.7% of the interviewees lived with family members, i.e. parents or grandparents. Analysis of the data concerning religious bonds showed that 67.6% of women declared their indifference to religion. conclusions. The economic factor was an important reason limiting procreation. The bad situation on the real estate market combined with an insufficient range of social welfare led to a decrease in the birth-rate in the Greater Poland region. The impact of religion on family planning was less important. The influence of the analysed socio-economic factors on family planning was similar in rural and urban areas

    Design and Application of Magnetic Photocatalysts for Water Treatment. The Effect of Particle Charge on Surface Functionality

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    Core-interlayer-shell Fe3O4/SiO2/TiO2, CoFe2O4/SiO2/TiO2 and BaFe12O19/SiO2/TiO2 magnetic photocatalysts were obtained. A water-in-oil microemulsion system with suitable surfactants was used for functionalization of the magnetic core with silica interlayer and TiO2-based photocatalyst. Uncoated and coated particles were characterized by electrophoretic measurements, X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), specific surface area (BET) measurements, diffuse reflectance spectroscopy (DRS) and vibrating sample magnetometer (VSM) analysis. The pH of the solution and corresponding zeta potential was found to be essential for appropriate formation of ferrite core/silica interlayer/TiO2 shell nanocomposite, since the electrical charge controls interactions during functionalization of the magnetic core particles. Thus, the development of multilayer structure in the isoelectric point (IEP) region enhanced adhesion of ferrite, silica and titania particles. The obtained Fe3O4/SiO2/TiO2, CoFe2O4/SiO2/TiO2 and BaFe12O19/SiO2/TiO2 nanocomposites revealed superparamagnetic behavior. The decomposition rate of phenol and carbamazepine allowed to estimate their photocatalytic activity. Progress of photocatalytic mineralization of organic compounds was evaluated by total organic carbon (TOC) measurements. Photocatalytic activity measured in four subsequent cycles showed good reusability as no loss of efficiency of phenol degradation was observed

    Zachowania zdrowotne i żywieniowe wybranej grupy pacjentów z Polski południowo-wschodniej: badanie pilotażowe

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    Background. The growing number of people with excess body weight is one of the most important global health issues. The increase in the number of people with excess weight and obesity leads to a shortened life expectancy. Material and methods. The aim of this pilot study was to use a questionnaire survey to determine the lifestyle of the people in a group of 84 Polish patients from south-eastern Poland, including diet, physical activity, and health. The pilot studies were carried out from December 2021 to January 2022 in a family doctor’s clinic among people in search of advice, who willingly volunteered themselves for the study. Results. The results of the study showed that 33% of women and 44% of men have excess body weight. Economic status statistically significantly affects the incidence of overweight and obesity. However, the level of education does not have a statistically significant effect on body weight. The irregularity of meals among the respondents was often explained by irregular work and many responsibilities. Our research also showed a low physical activity of the studied population. Conclusions. Improper nutrition combined with other anti-health behaviors make it significant to introduce intensive health education programs.Wprowadzenie. Wzrastająca liczba osób z nadmierną masą ciała jest jednym z najważniejszych globalnych problemów zdrowotnych. Wzrost liczby osób z nadwagą i otyłością prowadzi do skrócenia średniej długości życia. Materiał i metody. Celem badań pilotażowych było określenie za pomocą ankiety kwestionariuszowej stylu życia w 84-osobowej grupie polskich pacjentów z południowo-wschodniej Polski z uwzględnieniem diety, aktywności fizycznej i stanu zdrowia. Badania pilotażowe przeprowadzono od grudnia 2021 do stycznia 2022 w poradni lekarza rodzinnego wśród chętnych osób szukających porady lekarskiej. Wyniki. Wyniki badań wykazały, że 33% kobiet i 44% mężczyzn ma nadwagę. Status ekonomiczny statystycznie istotnie wpływa na występowanie nadwagi i otyłości. Natomiast poziom wykształcenia nieistotny statystycznie nie ma wpływu na masę ciała. Nieregularność posiłków wśród respondentów była często tłumaczona nieregularnością pracy i wieloma obowiązkami. Z naszych badań wynika również niska aktywność fizyczna badanej populacji. Wnioski. Niewłaściwe odżywianie w powiązaniu z innymi zachowaniami antyzdrowotnymi oraz mała aktywność fizyczna sprawiają, że ważne jest wprowadzenie intensywnych programów edukacji zdrowotnej
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