Measuring one physical quantity as a function of another often requires making some choices prior to the measurement process. Two these are: data range where measurements should focus and number (n) points acquire in chosen range. Here, we consider interval variation independent variable (x) that is associated with given dependent (y). We analyzed role width lower endpoint on parameter estimation by linear regression. show that, when feasible, increasing more effective than same reducing...

We report magnetoresistance curves of CoFe nano-oxide specular spin valves MnIr/CoFe/nano-oxidized CoFe/CoFe/Cu/CoFe/nano-oxidized CoFe/Ta at different temperatures from 300 to 20 K. extend the Stoner-Wolfarth model a common valve valve, introducing separation pinned layer into two sublayers and their magnetic coupling across nano-oxide. study effect coupling/exchange (between antiferromagnetic bottom sublayer) field ratios on magnetization magnetoresistance, corresponding with...

The specific heat (C(T)) of Gd4Co3 was measured in the temperature range 2–300 K and its magnetic contribution (Cm(T)) determined using a new method that fits electronic coefficient (γ) Debye (θD) by constraining resulting entropy (Sm(T)) to saturate at temperatures far above Curie (TC). Cm(T) exhibits low-temperature bump originating from thermal excitation gapped spin waves, which is responsible for pronounced peaks, ≈35 K, both Cm/T derivative electrical resistivity (dρm/dT). Apart...

The temperature and magnetic field dependences of the magnetoresistance (MR), superconducting quantum interference device magnetization M, its electrical resistance R derivative dR/dT (10–300 K) are reported for nonspecular CoFe/Cu/CoFe spin valves specular formed by nano-oxidation pinned free CoFe layers. MR(T) increases linearly with decreasing on both valves, data extrapolation converges to zero MR practically at same Curie temperature. At temperatures below ∼175 K valve MR(H) curves...

Abstract. This paper presents a work that aims to monitor seismo-electromagnetic phenomena in the Western Part of Eurasia-Nubia Plate Boundary. region has significant tectonic activity combined with relatively low electromagnetic noise levels, rendering high quality measurements possible. An overview seismicity this is presented and research plan discussed accordingly.

Abstract This work describes an exact radiometric model for experimental demonstrators of the detection exoplanets by transit method. generalises calculation depth occultation from standard method to case a finite size demonstrator apparatus. Results show that, apparatuses moderately small sizes, significant accuracy improvement in determination planet can be achieved using proposed comparison formula The radiance distribution star is found crucial importance, as deviations Lambertian lead...

We present a study of the spin disorder resistivity ([Formula: see text]) and electronic specific heat coefficient (γ) in Gd(4)(Co(1-x)Cu(x))(3) compounds, with x = 0.00, 0.05, 0.10, 0.20 0.30. The experimental results show strongly nonlinear dependence [Formula: text] on average de Gennes factor (G(av)) which, similar intermetallic is usually attributed to existence fluctuations Co 3d bands. Values γ were found around 110 mJ mol(-1) K(-2) for much larger than 38.4 isostructural nonmagnetic...

Here we report a detailed study providing complete H-T phase diagrams for both NdRu2Si2 and TbRu2Si2 intermetallic compounds, based on high resolution SQUID magnetization measurements, in the temperature range 2–300 K applied magnetic fields up to 5 T, using c-axis magnetically oriented powders. For NdRu2Si2, our results are good agreement with recent neutron diffraction work under fields, confirming appearance of an intermediate (temperature field) ferrimagnetic responsible two-step...

We describe a method for the exact data linearization of charging curve capacitor. The calculations required are as simple those involved in discharging curve, allowing analysis process using graphical and fitting tools available introductory physics courses. proposed can also be generalized to university-level problems involving biased exponential curves an input parameter estimation nonlinear procedures.

We report results of thermoelectric power measurements (S(T)) in ferrimagnetic Gd4(Co1-xCux)3 compounds with x = 0.05, 0.1, 0.2, and 0.3, the temperature range 8–300 K. Whereas Gd4Co3, S(T) is always negative, for > 0 substitution Co Cu gives rise to appearance a low positive maximum at around 30 Based on our previous study these compounds, we argue that this originates from electron-magnon scattering sensitive electron band structure changes resulting accompanying reduction ratio...

O albedo terrestre (A) representa a fração de radiação eletromagnética solar incidente na Terra (Ei) que é refletida para o espaço (Er):

We present a discussion of the magnetic properties and phase transitions Gd72Sc28 monocrystalline alloys based on experimental results magnetization (M) transport ( rho , d /dT, Delta / ). In particular, spin reorientation transition is observed in canted ferromagnetic phase. Using dM/dH d( )/dH data we have obtained H-T diagram this particular alloy composition as function basal plane applied field, H.

Low-temperature specific-heat measurements on the tetragonal ${\mathrm{TbRu}}_{2}$${\mathrm{Si}}_{2}$ intermetallic compound show existence of a magnetic transition at ${\mathit{T}}_{\mathit{c}}$=4.7 K, where [3/13,0,0] square modulated phase with moments directed along c axis was generally accepted to exist. Such transition, which exhibits all characteristic features \ensuremath{\lambda}-type order-disorder extended fluctuation effects both sides ${\mathit{T}}_{\mathit{c}}$ can be explained...

In order to study the effects caused by substituting Co for Cu on magnetic properties of Gd4(Co1−xCux)3 compounds with x=0.05, 0.1, 0.2, and 0.3, superconducting quantum interference device magnetization measurements were performed polycrystalline samples in temperature range 5–300 K using applied fields from 0 5 T. Experimental results show that substitution produces an increase anisotropy, which is accompanied important changes ordering these ferrimagnetic respect Gd4Co3. A T-x phase...

The ammeter-voltmeter method is a general for measuring electrical resistances that widely used in the introductory physics laboratory, mostly pedagogical reasons. Simultaneous readings of current (I) and voltage (V) allow calculation resistance (R) using Ohm’s law: R = V/I. It implicitly assumed wire contact present circuit can be neglected. Two configurations are usually proposed, depending on relative values internal ammeter voltmeter. In this work, we highlight deficiencies standard...

When conducting experiments involving the measurement of physically related quantities, choosing an appropriate spacing for experimental independent variable is a crucial procedure whose consequences may go beyond data graphical visualization. This particularly true if measured quantities are nonlinearly and errors nonuniform. In this work, we show that procedures should provide higher density points in range where larger, to more effectively average out random thus mitigate accuracy...

We report magnetization, neutron diffraction and elastic constant measurements of the single-crystal rare earth alloy Gd64Sc36 as a function magnetic field. For an a-axis field material exhibits transitions from helix to fan basal plane ferromagnet. At low temperatures looked-in structure is very sensitive application small fields (~5 mT).

We propose a method for formative assessment of laboratory work which provides running updated diagnostic the student performance and skills in all predefined areas sub-areas. The is easily adaptable to any type report or assessment, provided that graded profile can be defined.