No abstract

The study examines the relationship between political behaviors, e.g., ingratiation, structure change, cooptation, and threat, and their outcomes such as interpersonal trust, alienation, and feeling about job performance. A negative relationship between political behaviors and interpersonal trust andfeelings about performance, and a positive relationship between political behaviors and alienation is hypothesized. Results largely support the hypotheses. However, a relationship between political behaviors and feelings about job performance is marginal. Findings are discussed in the light of available research.

In an attempt to identify novel magnetic refrigerant materials, we have studied the magnetic and magnetocaloric properties in RNi compounds with R = Gd, Ho and Er. GdNi is a simple ferromagnet with a collinear structure in contrast to HoNi and ErNi, in which the moments of rare earth sublattice are arranged non-collinearly. The magnetic ordering temperatures are observed to be 69 K, 36.5 K and 10 K for GdNi, HoNi and ErNi, respectively. The maximum values of magnetocaloric effect are found to be 17 J kg−1 K−1, 15 J kg−1 K−1 and 29 J kg−1 K−1 for Gd, Ho and Er, respectively, for an applied field of 50 kOe. The relative cooling power has been calculated to be 527 J kg−1 K−1, 780 J kg−1 K−1 and 510 J kg−1 K−1 for GdNi, HoNi and ErNi. These values compare well with those of many potential materials whose magnetic transitions are in the same range as in the present case.

We analyse the locking phenomena arising when an external-cavity diode laser is subjected to optical injection from another uncontrolled diode laser. The system stability is investigated as a function of coupled cavity time delay and the optical injection strength. Different regimes, spanning from ‘in-phase locking’ to ‘out-of-phase locking’ with ultimate amplitude death of low-frequency fluctuations/pulsations, are described experimentally as well as numerically for weak to moderate injection. Qualitative agreements between numerically and experimentally observed results for amplitude quenching are shown. Numerical studies describe the shifting of phase-flip bifurcation as the optical injection strength is varied for a particular time delay. Stable phase-locking behaviours, which are desired from the point of view of practical applications, are observed numerically in a wide range of control parameter space.

We report a detailed magnetic, magnetocaloric, and magnetotransport study on R 2 Ni 2 Sn compounds with different rare earths. The magnetic state of these compounds is found to be complex because of the coexistence of ferromagnetic and antiferromagnetic components. These compounds show phenomena such as multiple magnetic transitions, nonsaturation of magnetization, and metamagnetic transitions. Analysis of the zero-field heat capacity data shows that the magnetic entropy is less than the theoretical value, indicating the presence of some moment on Ni. Schottky anomaly is present in the magnetic heat capacity data of Sm 2 Ni 2 Sn. The temperature variation of magnetocaloric effect reflects the magnetization behavior. Tb 2 Ni 2 Sn and to a less extent Gd 2 Ni 2 Sn show oscillatory magnetocaloric effect. The variation of magnetocaloric effect is correlated with the ferromagnetic-antiferromagnetic phase coexistence. The electrical resistivity analysis has shown that the electron-magnon scattering is prominent at low temperature, while phonon scattering modified by the s-d interaction is crucial at high temperatures. The magnetoresistance is very large in Ce 2 Ni 2 Sn and shows a quadratic dependence on the field, implying the role of spin fluctuations in determining the transport behavior. Large magnetoresistance has been observed in other compounds as well.

We have studied the variation of magnetic and magnetocaloric properties of polycrystalline compounds SmMn 2 Ge 2 and GdMn 2 Ge 2 as a function of applied hydrostatic pressure. The magnetic transition temperatures are found to change considerably with pressure. The temperature regime of existence of antiferromagnetic ͑AFM͒ ordering is found to increase with pressure, in both the compounds. In SmMn 2 Ge 2 , the sign of the magnetocaloric effect at the low-temperature ferromagnetic ͑FM͒-AFM transition changes with pressure. The isothermal magnetic entropy change in this compound is found to increase by about 20 times as the pressure is increased from the ambient value to 6.8 kbar. Effect of pressure in GdMn 2 Ge 2 is less compared to that in SmMn 2 Ge 2 . The variations in the magnetic and magnetocaloric properties are attributed to the changes in the magnetic state of the Mn sublattice under pressure. The difference in R-Mn coupling in Sm and Gd compounds is also found to play a role in determining the magnetic and magnetocaloric properties, both at ambient as well as under applied pressures.

Magnetic, magneto-thermal and magneto-transport properties investigated in R2Al compounds reveal interesting aspects regarding the magnetic state of these compounds. The coexistence of ferro and antiferro magnetic order is seen to determine the magnetic and other related properties. The crystal field effect is found to be significant in Nd and Tb compounds, as revealed by the magnetization and heat capacity data. The sign of the isothermal magnetic entropy change reflects the nature of magnetic transitions. The magnetic entropy change is found to be significant in all the three compounds, with Tb2Al showing the maximum value of 12 J kg−1 K−1. Like the entropy change, the magnetoresistance (MR) also shows different signs, reflecting the magnetic state. At low temperatures, all the compounds show very large MR.

The effect of distributed exchange parameters on magnetocaloric refrigeration capacity in amorphous and nanocomposite materials J. Appl. Phys. 111, 07A334 (2012) Particle size dependent hysteresis loss in La0.7Ce0.3Fe11.6Si1.4C0.2 firstorder systems Appl. Phys. Lett. 100, 072403 (2012) Magnetocaloric effect and refrigerant capacity in 0.44, 0.46 The effect of Ge substitution on the magnetization, heat capacity, magnetocaloric effect, and magnetoresistance of GdMn 2 Si 2−x Ge x ͑x = 0, 1, and 2͒ compounds has been studied. The magnetic transition associated with the Gd ordering is found to change from second order to first order on Ge substitution. Magnetic contributions to the total heat capacity and the entropy have been estimated. Magnetocaloric effect has been calculated in terms of adiabatic temperature change ͑⌬T ad ͒ as well as isothermal magnetic entropy change ͑⌬S M ͒ using the heat capacity data. The temperature dependence of the magnetocaloric effect in all the three compounds have shown broad peaks. The maximum values of ⌬S M and ⌬T ad for GdMn 2 Ge 2 are found to be 5.9 J / kg K and 1.2 K, respectively. The magnetoresistance is found to be very large and positive with a maximum value of about 22% in the case of GdMn 2 Ge 2 . In the other two compounds also, the magnetoresistance is predominantly positive, except in the vicinity of the Gd ordering temperature. The anomalous nature of the magnetocaloric effect and the magnetoresistance has been attributed to the canted magnetic structure of these compounds.