62 research outputs found
130 nm low power CMOS analog multiplier
Processing analog signal often involves analog multiplier and the multiplier is part of system on chip (SoC). Designing such system with a low power consumption is crucial nowadays. It is very important to increase the system battery lifetime. The design also must be smaller in size. In order to reduce the power consumption of the multiplier, an architecture that require smaller current must be designed and the approach is to use a design that is able to function at a low voltage supply. This project has designed the analog multiplier with a low power consumption using Silterra 130 nm Complementary Metal Oxide Semiconductor (CMOS) technology. A four quadrant technique is applied in the design. The scaling of transistor will help in reducing the size of the analog multiplier, and the proposed circuit architecture has produced a compact multiplier. Cadence electronic design automation (EDA) Tools is used to design the circuit. The schematic, layout, physical verification and parasitic extraction with post layout simulation are done to verify the multiplier circuit is functioning. The analog multiplier is operated with 1.2 V voltage supply and the power consumption is 98 μW. At 1 V, the power consumption is 32 μW. The total area for the design is 99 μm²
Effect of Ca substitution on crystal structure and superconducting properties of ferromagnetic superconductor RuSr2-xCaxGd1.4Ce0.6Cu2O10-delta
We have investigated the effect of Ca substitution for Sr site on structural, magnetic and superconducting properties of RuSr2-xCaxGd1.4Ce0.6Cu2O10-delta system. In this system, the magnetic coupling of RuO2 and CuO2 plays an important role in magnetic and superconducting states. X-ray diffraction analysis shows that all samples are single phase and the lattice parameters decrease continuously by increasing Ca content. The onset superconducting transition temperature is found to decrease with Ca substitution. As Ca content increases, rotation of the RuO6 octahedron increases and Ru-O(1)-Ru angle decreases. These variations strengthen the magnetic moments in the RuO2 planes. The enhancement of weak ferromagnetic component and hole trapping by Ru magnetic moments in RuO2 planes reduces the electrical conduction, and destroys the superconducting state in the system. Analysis of the resistivity data (rho) based on the hoping conduction mechanism, indicates a variation of the hoping exponent (p) across the magnetic transition at T-m. The hoping exponent p is not affected sharply by Ca concentration. (C) 2011 Elsevier B.V. All rights reserved
Phase diagram with an enhanced spin-glass region of the mixed Ising-<em>XY</em> magnet LiHo<sub><em>x</em></sub>Er<sub>1<em>-x</em></sub>F<sub>4</sub>
We present the experimental phase diagram of LiHoxEr1 xF4, a dilution series of dipolar coupled model magnets. The phase diagram was determined using a combination of ac susceptibility and neutron scattering. Three unique phases in addition to the Ising ferromagnet LiHoF4 and the XY antiferromagnet LiErF4 have been identified. Below x 0.86, an embedded spin glass phase is observed, where a spin glass exists within the ferromagnetic structure. Below x 0.57, an Ising spin glass is observed consisting of frozen needlelike clusters. For x amp; 8764; 0.3 0.1, an antiferromagnetically coupled spin glass occurs. A reduction of TC x for the ferromagnet is observed which disobeys the mean field predictions that worked for LiHoxY1 xF4
Crystal growth and characterization of the dilutable frustrated spin-ladder compound Bi(Cu1-xZnx)(2)PO6
High quality centimeter size single crystals of Bi(Cu1-xZnx)(2)PO6 (x=0% 1% 5%) have been successfully grown by the Travelling Solvent Floating Zone (TSFZ) technique The crystals were grown with a rate of 1 mm/h in a gas mixture of 20% O-2 in Ar Characterization of the single crystal samples by means of optical microscopy X-ray powder diffraction X-ray Laue diffraction neutron diffraction and magnetization measurement are reported The magnetic susceptibility lambda(spin)(T) measured from 2 to 300 K passes a broad maximum around 60 K followed by an exponential decrease towards lower T and confirm the formation of a spin singlet ground state at low temperature At low-temperature a paramagnetic Curie-like upturn quantitatively reflect the increasing Zn-doping level (C) 2010 Elsevier B V All rights reserve
Phase diagram of diluted Ising ferromagnet LiHoxY1−xF4
We present a systematic study of the phase diagram of LiHoxY1−xF4 (0.25≤x≤1) Ising ferromagnets obtained from neutron scattering measurements and mean-field calculations. We show that while the thermal phase transition decreases linearly with dilution, as predicted by mean-field theory, the critical transverse field at the quantum critical point is suppressed much faster. This behavior is related to competition between off-diagonal dipolar coupling and quantum fluctuations that are tuned by doping and applied field, respectively. In this paper, we quantify the deviation of the experimental results from mean-field predictions, with the aim that this analysis can be used in future theoretical efforts towards a quantitative description
Corrosion behavior of friction stir welded lap joints of AA6061-T6 aluminum alloy
In this work, the corrosion behaviors of friction-stir lap welding of 6061-T6 Al-alloy are studied. The friction-stir lap welding was performed under different welding conditions (rotation speed and welding speed). The corrosion behavior of the parent alloy, the weld nugget zone (WNZ), and the heat affected zone (HAZ) of each welded sample working as an electrode, were investigated by the Tafel polarization test in 3.5 wt. (%) NaCl at ambient temperature. The morphology of the corroded surface of each region was analyzed by scanning electron microscopy together with energy dispersive spectroscopy (SEM-EDS). The results showed that the corrosion resistance of the parent alloy was better than the WNZ and the HAZ in both welding conditions. Localized pit dissolution and intergranular corrosion were the dominant corrosion types observed in the parent alloy, WNZ, and HAZ. The parent alloy, WNZ, and HAZ exhibited similar corrosion potentials (Ecorr) after T6 heat treatment. This treatment had a better effect on the corrosion resistance of the welded regions than the parent alloy
Crystal growth and characterization of the dilutable frustrated spin-ladder compound Bi(Cu1−xZnx)2PO6
Frequency and clinical patterns of stroke in Iran - Systematic and critical review
<p>Abstract</p> <p>Background</p> <p>Cerebrovascular disease is the second commonest cause of death, and over a third of stroke deaths occur in developing countries. To fulfil the current gap on data, this systematic review is focused on the frequency of stroke, risk factors, stroke types and mortality in Iran.</p> <p>Methods</p> <p>Thirteen relevant articles were identified by keyword searching of PubMed, Iranmedex, Iranian University index Libraries and the official national data on burden of diseases.</p> <p>Results</p> <p>The publication dates ranged from 1990 to 2008. The annual stroke incidence of various ages ranged from 23 to 103 per 100,000 population. This is comparable to the figures from Arab Countries, higher than sub-Saharan Africa, but lower than developed countries, India, the Caribbean, Latin America, and China. Similarly to other countries, ischaemic stroke was the commonest subtype. Likewise, the most common related risk factor is hypertension in adults, but cardiac causes in young stroke. The 28-day case fatality rate is reported at 19-31%.</p> <p>Conclusions</p> <p>Data on the epidemiology of stroke, its pattern and risk factors from Iran is scarce, but the available data highlights relatively low incidence of stroke. This may reflect a similarity towards the neighbouring nations, and a contrast with the West.</p
First measurement of neutrino oscillation parameters using neutrinos and antineutrinos by NOvA
The NOvA experiment has seen a 4.4σ signal of ν̄e appearance in a 2 GeV ν̄μ beam at a distance of 810 km. Using 12.33×1020 protons on target delivered to the Fermilab NuMI neutrino beamline, the experiment recorded 27 ν̄μ→ν̄e candidates with a background of 10.3 and 102 ν̄μ→ν̄μ candidates. This new antineutrino data are combined with neutrino data to measure the parameters |Δm322|=2.48-0.06+0.11×10-3 eV2/c4 and sin2θ23 in the ranges from (0.53-0.60) and (0.45-0.48) in the normal neutrino mass hierarchy. The data exclude most values near δCP=π/2 for the inverted mass hierarchy by more than 3σ and favor the normal neutrino mass hierarchy by 1.9σ and θ23 values in the upper octant by 1.6σ
First measurement of neutrino oscillation parameters using neutrinos and antineutrinos by NOvA
The NOvA experiment has seen a
4.4
σ
signal of
¯
ν
e
appearance in a 2 GeV
¯
ν
μ
beam at a distance of 810 km. Using
12.33
×
10
20
protons on target delivered to the Fermilab NuMI neutrino beamline, the experiment recorded 27
¯
ν
μ
→
¯
ν
e
candidates with a background of 10.3 and 102
¯
ν
μ
→
¯
ν
μ
candidates. This new antineutrino data are combined with neutrino data to measure the parameters
|
Δ
m
2
32
|
=
2.4
8
+
0.11
−
0.06
×
10
−
3
eV
2
/
c
4
and
sin
2
θ
23
in the ranges from (0.53–0.60) and (0.45–0.48) in the normal neutrino mass hierarchy. The data exclude most values near
δ
C
P
=
π
/
2
for the inverted mass hierarchy by more than
3
σ
and favor the normal neutrino mass hierarchy by
1.9
σ
and
θ
23
values in the upper octant by
1.6
σ
- …