The series M
0.5(1+
x
)
Fe
x
Zr
2−
x
(PO
4
)
3
(M—Ni, Cu, Mn) with Sc
2
(WO
4
)
3
-related structure (SW) were prepared using Pechini technique and characterized by powder X-ray diffraction analysis, ...SEM, EDX, IR, and Mössbauer spectroscopy. The concentration and temperature limits of solid solution formation were determined, lattice parameters were calculated, and their dependencies on the phosphate’s composition were studied. The crystal structure of the phosphate Mn
0.65
Fe
0.3
Zr
1.7
(PO
4
)
3
(
x
= 0.3) was refined by the Rietveld method basing on the powder X-ray diffraction data. The compound crystallizes in monoclinic symmetry (space group
P
2
1
/
n
) with lattice parameters:
a
= 8.7941(12),
b
= 8.9379(16),
c
= 12.4353(21) Å,
β
= 90.126(24)°,
V
= 977.49(27) Å
3
. Thermal expansion coefficients of the ceramics Cu
0.5(1+
x
)
Fe
x
Zr
2−
x
(PO
4
)
3
were determined. The volume expansion coefficients of the compounds vary in the range (4.4–10.8)∙10
−5
K
−1
.
Highlights
New zirconium phosphate ceramics M0.5
(1+x)
FexZr
2
-x(PO
4
)
3
(M – Ni, Cu, Mn; structural type SW) were synthesized, the formation regions of the solid solutions were revealed.
Temperature stability of the phosphates was determined.
Crystal structure of the triple phosphate Mn
0.65
Fe
0.3
Zr
1.7
(PO
4
)
3
was refined by Rietveld method.
Thermal expansion behavior was studied by XRD, possible reasons were discussed.
Gyroscopes and accelerometers form the core of Electronic Stability Control (ESC) systems 1, which are mandated for new vehicles in many countries. Gyroscopes for ESC applications require higher ...performance specifications than those of consumer gyroscopes available in the market today. In addition, they require continuous safety monitoring so that changes in the output, which happen in the field due to MEMS and circuit malfunctions, are flagged and are not misconstrued for legitimate signals. This work presents a low-overhead approach for implementing accurate continuous safety monitoring by augmenting the function of already existing sub-systems. In addition, the paper discusses circuit architecture and design techniques, which achieve the stringent ESC specifications for noise, robustness to parasitic resonant modes in the sensor element and offset drift due to temperature and Electro-Magnetic Interference (EMI).
Electrochemical chromium coatings modified with diamond nanoparticles (ND) were deposited on sintered steel materials obtained from iron powder and ultrafine graphite powder. The diamond ...nanoparticles were produced by detonation synthesis. Their average size is 6 nm. The sintered steel consisted of 0.2, 0.4, 0.6 and 0.8%C (added in the form of graphite) by weight. The produced composite coatings consisting of Cr + ND were compact, tightly adhering to the substrate, with thickness of about 25–35 μm. The surface morphology and microstructure of the coatings were investigated by SEM and EDS analyzes. The main objective of the study was to explore the presence of ND in the coating by the X-ray photoelectron spectroscopy and the impact of the ND concentration in the electrolyte on the presence of the diamond nanoparticles in the coating. The spectra of the C1
s
photoelectronic line were obtained, the
sp
3
/
sp
2
ratio and the
sp
3
+
sp
2
sum were determined electronically on the surface of the coatings (depth 10 nm). The Cr2p photoelectronic line spectra were also obtained. The coatings were deposited from electrolytes with ND concentrations of 10, 25 and 40 g/l. A diamond-like phase has been found in coatings obtained at concentrations of diamond nanoparticles in the electrolyte of 25 and 40 g/l. The
sp
3
/
sp
2
ratio with a value equal to or greater than 1.2 is an indication of the presence of a diamond-like phase in the coatings and the ratio depends on the concentration of ND in the electrolyte.
This paper studies the commitment value of delegation in a model of dynamic competition. We argue that separating ownership and control delivers an instantaneous first-mover advantage. Thus, ...delegation would enable an oligopolistic firm to increase its equilibrium profit relative to direct management. We focus on remuneration strategies that provide managers with intertemporal production incentives: future wages depend on current effort. Their composition and functional form are endogenously determined by the requirement for Markov perfection. For the case of linear-quadratic payoffs, we obtain a closed-form solution for the equilibrium wage strategies which is independent of industry structure.
A 4-GS/s current-domain analog front end (CurAFE) for phase-coded pulse-compression direct time-of-flight (dTOF) automotive Lidar has been realized in 130-nm CMOS. The permissible eye-safe laser ...energy is transmitted in the form of a burst of optical sub-pulses. The burst embeds a phase coding designed to have an auto-correlation function with a maximum peak-to-sidelobe ratio. The optical reflection of this burst, reflected from a target, is then detected by an avalanche photodiode (APD). The APD's output current drives the CurAFE, whose 4-GS/s single-bit output is processed by a digital matched filter for pulse-compression and TOF estimation through cross correlation. The 200-MHz bandwidth frontend detects bursts with bitrates up to 200 Mb/s (5-ns sub-pulsewidth) and is designed for >80-dB DR without saturation and 5-pA/<inline-formula> <tex-math notation="LaTeX">\surd </tex-math></inline-formula>Hz input-referred noise. A current-feedback dc servo loop at its input cancels the background-light-induced detector current. Compared to state-of-the-art single-pulse Lidars, operating with peak optical transmit powers ~50 W, this work achieves an inaccuracy of 0.225 m (1<inline-formula> <tex-math notation="LaTeX">\sigma </tex-math></inline-formula>) over 60-m range at >10<inline-formula> <tex-math notation="LaTeX">\times </tex-math></inline-formula> lower peak transmit power of ~3.5 W.
Purpose The aim of present work was to investigate microstructure and mechanical properties of 3D printed by selective laser melting (SLM) Co- Cr alloys, intended for additive manufacturing in ...dentistry. Methods A scanning electron microscope (SEM), equipped with an integrated Energy-Dispersive X-Ray Spectroscopy (EDS) system was used for investigation of the surface morphology and elemental composition of the 3D- printed Co-Cr sample. The X-ray structural analysis of the 3D - printed Co-Cr sample was made with a Bruker D8 Advance powder X-ray diffractometer. An Atomic force microscopy (AFM) was used for investigation of the surface topography of the sample. Tensile test, a three-point bending test, and nanoindentation experiments were used for investigation of mechanical properties of the 3D-printed Co-Cr sample.The influence of two different strain rates (1 mm/min and 60 mm/min) on the flexural strength was investigated as well. Results Higher values of indentation hardness (6.76 GPa), tensile strength (1016 MPa), yield strength (636.5 MPa) and flexural strength (1908 and 1891 MPa) of the produced by selective laser melting Co-Cr alloys have been obtained compared to cast Co-Cr and Cr-Ni alloys. It was found that increasing the strain rate from 1 mm/min to 60 mm/min caused a proportional increase in recorded flexural strength of ~0.9%. Conclusions The obtained results showed that the laser-sintered Co-Cr alloy can fully replace the cast Co-Cr alloy in dentistry, regards as of its good mechanics properties, as well as the high precision of the final product.
Motility patterns of spermatozoa are an indicator of their fertilizing capacity. Reduced glutathione (GSH) has been reported to induce positive effects on the biological quality of the frozen-thawed ...spermatozoa. The aim of this study was to investigate the effects of GSH addition to semen extender based on the following kinetic parameters: continuous line velocity (VSL), average path velocity (VAP), curvilinear velocity (VCL), amplitude of lateral head displacement (ALH), linearity (LIN), straightness (STR), beat cross frequency (BCF), total motility (tMOT) and progressive motility (pMOT), and to appoint them as indicators of its presence. A soybean-based extender was used for dilution of the semen samples, fractioned in two parts, one containing GSH (5 mMol/ml) and second without GSH. The ejaculates (n=48) were collected from two rams (January - May, 2013) which were classified in two groups according to the used extender: Group 1 (with GSH, n=24) and Group 2 (without GSH, n=24), and then frozen in liquid nitrogen on -196°C degrees in a programmable freezer. Assessment of the samples has been performed post-thawing (30 sec. at 37°C) on CASA equipment, acquiring kinetic parameters. Results showed that only VSL and BCF have a statistically significant difference between group1 and group 2 (102.98±15.13 vs. 88.47±20.63, t=2.77, p<0.01 and 32.01±2.68 vs. 89.47±2.92, t=3.13, p<0.01, respectively). The summary of the investigation concludes that none of the kinetic parameters could be appointed as indicators that confer the positive effect of GSH as an additive to soy-bean semen extender.
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