We have summarized our data and literature ones on the thermophysical properties and hydrolytic stability of Sr0.5Zr2(PO4)3 compound as a host NaZr2(PO4)3-type (NZP) structure for immobilization of ...90Sr-containing radioactive waste. Absence of any polymorphic transformations on the temperature dependence of its heat capacity between 7 and 665 K is caused by the stability of crystalline Sr0.5Zr2(PO4)3. Calculated values of thermal conductivity coefficients at zero porosity in the range 298–673 K were 1.86–2.40 W·m−1 K−1. The compound may be classified as low thermal expanding material due to its average linear thermal expansion coefficient. Study of the hydrolytic stability in acid and alkaline media has shown that the relative mass fraction of Sr2+ ions, released into aggressive leaching media, didn't exceed 1% of the mass of sample. Soxhlet leaching studies have shown substantial resistance towards the release of Sr2+ ions into distilled water. Feeble sinterability constrains practical applications of NZP substances, that is why known in literature methods of Sr0.5Zr2(PO4)3 dense ceramics obtaining have been reviewed.
The ability of Sr0.5Zr2(PO4)3 using as a perspective nuclear waste form, resistant to radiation damage, has been investigated. The obtained results highlight several concerns with application of Sr0.5Zr2(PO4)3 material as a host matrix, which is stable to extreme environmental condition action and able to include 90Sr radioisotope into insoluble framework structure. Display omitted
•The ability of Sr0.5Zr2(PO4)3 using as a nuclear waste form was investigated.•Its heat capacity, thermal expansion and thermal conductivity were studied.•Its stability in distilled water, aggressive (acid and alkaline) media was confirmed.•The possibility of Sr0.5Zr2(PO4)3 dense ceramics sintering have been examined.•Our data and literature ones were compared.
A three-axis automotive gyroscope ASIC for electronic stability control (ESC) with noise density that is less than 0.004°/s/√Hz in a 80 Hz bandwidth and an offset drift lower than ±0.1°/s over the ...automotive temperature range -40 to 140 °C, without any temperature compensation, is reported. A closed-loop, force-feedback architecture along with electromechanical quadrature cancellation enables the low noise and low offset-drift performance. The application of this work needs to meet the ASIL-D automotive safety standard which requires the highest level of automotive safety. Therefore, this work also presents a low-overhead approach for implementing accurate continuous safety monitoring to monitor defects, which can develop in the field, and can give rise to a false output. To achieve this, two test signals are injected into the quadrature cancellation loop to traverse the entire signal path. The system is clocked by a low-phase noise PLL, which allows the coexistence of the test signals and the measured signal in close proximity, without a noise penalty. The architecture of the drive loop is chosen to not only achieve low-phase noise but also robustness to parasitic mechanical modes of the sensor.
The aim of our study was to analyse immune abnormalities in patients with chronic infected diabetic foot ulcers (DFUs) especially those infected by resistant microorganisms. Methods. 68 patients ...treated in our foot clinic for infected chronic DFUs with 34 matched diabetic controls were studied. Patients with infected DFUs were subdivided into two subgroups according to the antibiotic sensitivity of causal pathogen: subgroup S infected by sensitive (n=50) and subgroup R by resistant pathogens (n=18). Selected immunological markers were compared between the study groups and subgroups. Results. Patients with infected chronic DFUs had, in comparison with diabetic controls, significantly reduced percentages (p<0.01) and total numbers of lymphocytes (p<0.001) involving B lymphocytes (p<0.01), CD4+ (p<0.01), and CD8+ T cells (p<0.01) and their naive and memory effector cells. Higher levels of IgG (p<0.05) including IgG1 (p<0.001) and IgG3 (p<0.05) were found in patients with DFUs compared to diabetic controls. Serum levels of immunoglobulin subclasses IgG2 and IgG3 correlated negatively with metabolic control (p<0.05). A trend towards an increased frequency of IgG2 deficiency was found in patients with DFUs compared to diabetic controls (22% versus 15%; NS). Subgroup R revealed lower levels of immunoglobulins, especially of IgG4 (p<0.01) in contrast to patients infected by sensitive bacteria. The innate immunity did not differ significantly between the study groups. Conclusion. Our study showed changes mainly in the adaptive immune system represented by low levels of lymphocyte subpopulations and their memory effector cells, and also changes in humoral immunity in patients with DFUs, even those infected by resistant pathogens, in comparison with diabetic controls.
A qualitative game describes a situation in which antagonistic players strive to keep the evolutions of their state variables in predetermined constraint sets. We argue that a qualitative game model ...is a suitable mathematical representation of the struggle between a domestic central bank of a small open economy and a foreign central bank of a large economy to maintain their respective state variables within an acceptable band regardless of the other player’s choices. The actions of the foreign central bank affect the domestic exchange rate and, hence, domestic inflation, output gap and interest rate. However, these actions do not necessarily aim to destabilise the small open economy, nor do they take into account the state of the latter. The domestic bank’s problem, therefore, is similar to that of a game against nature. We refer to this type of qualitative game as a nuisance-agent game (or NA-game). We use viability theory to derive satisficing rules (in the sense of Simon) of nominal interest-rate adjustments for the domestic central bank of a small open economy in a qualitative NA-game against the foreign central bank.
The mechanical properties, structure, and morphology of milled and 3D-printed Ti-6Al-4V alloys produced by selective laser melting were investigated in this study. The mechanical properties were ...investigated by means of nanoindentation, a tensile test, and a three-point bending test. An Atomic Force Microscope (AFM) was used to study the surface topography and roughness of both titanium alloys. The surface structure and phase analyses were studied by a scanning electron microscope (SEM) and through powder X-ray diffraction (XRD). The results from the nanoindentation experiments showed that the 3D-printed sample has higher indentation hardness and modulus than the milled one. The AFM observation of the surface topography of the samples showed that the milled sample has a higher roughness than the 3D-printed one. The tensile test results showed that the 3D-printed sample by means of Selective Laser Melting (SLM) technology has about 26% higher tensile strength and smaller elongation than the milled one. The three-point bending test revealed that the 3D-printed Ti-6Al-4V sample has higher flexural strength than the milled one. It was found that the 3D-printed sample has a smaller crystal size than the milled one, which, according to the Hall–Petch relationship, leads to its higher indentation hardness.
This paper examines an infinite-horizon multi-stage contest between two players. In each period, their effort may contribute to a joint prize pool, but also generates private costs. The player who ...works harder is awarded a larger share of the current prize pool, while his opponent receives the remainder. The stages of the supergame are linked through delayed effects of effort on subsequent prizes. The state equation and the prize pool are assumed to have a piecewise linear structure, allowing for both static and intertemporal rank-order effects. Under specific conditions, our game has an equilibrium in which the players use state-contingent mixed strategies with continuous support. We characterize the equilibrium mixing distributions, expected effort levels and payoffs. Then we illustrate our analysis with several examples.
New phosphates Zn0.5(1+x)FexM2-x(PO4)3 (M = Zr, Hf; 0 ≤ x ≤ 2.0) were synthesized via sol-gel and solid-state methods. The obtained solid solutions were characterized by X-ray diffraction, IR ...spectroscopy, electron microscopy and microprobe analysis. It was established that the phosphates crystallize in the structural types of Sc2(WO4)3 (SW) and NaZr2(PO4)3 (NZP). Rietveld refinement was implemented for structure of the phosphates Zn0.7Fe0.4Zr1.6(PO4)3 and Zn0.85Fe0.7Hf1.3(PO4)3 to be characterized. The formation regions of the solid solutions were revealed, and the temperature stability of the samples was also determined. Different limits of solid solutions were defined for the zirconium phosphates which had been synthesized via sol-gel and solid-state methods, and the reason for that is the low thermal stability of the SW-phosphates with high x values.
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•New phosphates Zn0.5(1+x)FexM2-x(PO4)3 (M = Zr, Hf; 0 ≤ x ≤ 2.0) were synthesized.•The formation regions of the solid solutions were revealed.•Temperature stability of the samples was determined.•Crystal structures of the Zn0.7Fe0.4Zr1.6(PO4)3 and Zn0.85Fe0.7Hf1.3(PO4)3 were refined by Rietveld method.
This note examines a complete-information contest with non-linear rank-order effects. The players’ payoffs incorporate a multiplicative term that allows for negative productivity spillovers. Under ...certain conditions, our game has a symmetric mixed-strategy equilibrium. To characterize this equilibrium, we adapt a method originally developed for linear settings. We obtain closed-form solutions for the mixing distribution, as well as for the expected efforts and payoffs. The note also explores the implications of negative productivity spillovers for optimal contest design. We show that a planner who seeks to maximize the participants’ expected payoffs may choose interior values for her instruments. We derive simple expressions for these values.
•We develop a method for analysis of contests with productivity spillovers.•We find closed-form solutions for expected efforts, payoffs and effort distributions.•We characterize the optimal choices of a designer who maximizes expected payoffs.•Negative productivity spillovers imply that optimal contest design may be interior.
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