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In this paper, we deal with the invertible elements in a complete intuitionistic fuzzy pseudo normed algebra (in short, IFPNA) with respect to Archimedean t-norm and Archimedean t-conorm. It is done by studying the continuity of algebraic operations in a complete IFPNA and investigating the condition for existence of inverse of an element in a complete IFPNA. Also some properties of invertible elements are studied. It is observed that the set of invertible elements in a complete IFPNA is an open set.

The structural and magnetic properties of as-cast Mn 1-x Al x CoGe (0 ≤ x ≤ 0.05) have been studied by X-ray diffraction, differential scanning calorimetry, and magnetization measurements. The partial substitution of Al for Mn in Mn 1-x Al x CoGe results in a decrease in the martensitic transition temperature T M . For the concentration range 0 ≤ x ≤ 0.01, T M was found to coincide with ferromagnetic transition temperature (T C ) resulting in a first-order magnetostructural transition (MST). A further increase in aluminum concentration resulted in a splitting of the phase transition temperatures, which included a drastic decrease in the martensitic temperature. The compounds with x > 0.02 showed a single transition at T C . The maximum values of the magnetic entropy changes (-ΔS M ) were ∼18 J/kgK, 12 J/kgK, and 7 J/kgK for ΔH = 5T at 313 K (x = 0.00), 286 K (x = 0.01), and 220 K (x = 0.02), respectively. The maximum value of the relative cooling power (RCP) was found to be 303 J/kg for x = 0.01 at T = 286 K for ΔH = 5T. It has been established that as-cast samples of this system show large value of MCE near room temperature making this system a promising material for magnetic cooling technologies.

We consider the problem of variable selection in linear regression using mixtures of g-priors. A number of mixtures have been proposed in the literature which work well, especially when the number of regressors p is fixed. In this paper, we propose a mixture of g-priors suitable for the case when p grows with the sample size n, more specifically when $$p=O(n^b)$$ , $$0

The magnetic properties and reversibility of the magnetocaloric effect of Ni 50 Mn 35 In 15 have been studied in the vicinity of the phase transition using magnetization and direct adiabatic temperature change (ΔT ad ) measurements in magnetic fields up to 14 T. The magnetostructural phase transitions (MSTs) between a martensitic phase (MP) with low magnetization (paramagnetic or antiferromagnetic) and a nearly ferromagnetic austenitic phase were detected from thermomagnetic curves, M(T,H), at the applied magnetic fields up to 5 T. The MST temperature was found to be nearly independent of magnetic field for H ad ∼ −11 К for a magnetic field change of ΔH = 14 T was observed in the vicinity of the MST. The irreversibility of ΔT ad was found to be 1 K. A direct ΔT ad of +7 K for ΔH = 14 T was detected at the second order ferromagnetic-paramagnetic phase transition. The obtained results have been discussed in terms of the suppression of antiferromagnetic correlations with the application of a strong magnetic field, and a reversibility of the initial magnetic state of the MP with applied magnetic field when the MST coincides with T C .

The magnetostructural transition (MST) can be tuned close to room temperature for an isostructurally alloyed (MnNiGe)1−x(Fe2Ge)x (x = 0.1) compound by partially substituting a small amount of Si for Ge (7 at. %). In this study, the effect of hydrostatic pressure (p) on MST is investigated. In comparison to purely magnetically induced phase transition, pressure initiates structural transition more abruptly, which results in an increase in the isothermal entropy change by a factor of 2 from −Δs = 25.6 (p = 0) to 45.6 J/kg K (p = 190 MPa) for a magnetic field change of 2 T. Since the direct assessment of the adiabatic temperature change, ΔTad, is difficult due to the large volume change and subsequent structural breakdown at MST, an indirect method has been employed to estimate ΔTad.

The crystal structure, magnetic and transport properties, including resistivity and thermopower, of Ni 50 Mn 18.75 Cu 6.25 Ga 25 and Ni 49.80 Mn 34.66 In 15.54 Heusler alloys were studied in the (10–400) K temperature interval. We show that their physical properties are remarkably different, thereby pointing to different origin of their magnetostructural transition (MST). A Seebeck coefficient ( S ) was found to pass minimum of about −20 µV/K in respect of temperature for both compounds. It was shown that MST observed for both compounds results in jump-like changes in S for Ga-based compound and jump in resistivity of about 20 and 200 µΩ cm for Ga and In –based compounds, respectively. The combined analyzes of the present results with that from literature show that the density of states at the Fermi level does not change strongly at the MST in the case of Ni–Mn–In alloys as compared to that of Ni–Mn–Ga.

Single crystals of LnCo2Al8 (Ln = La–Nd, Sm, Yb) were grown via the metal-flux growth technique and characterized by single crystal X-ray diffraction. LnCo2Al8 adopts the CaCo2Al8-structure type with space group Pbam and unit cell dimensions of a ≈ 12.4 A, b ≈ 14.4 A, and c ≈ 4.0 A. The unit cell volume of LnCo2Al8 (Ln = La–Nd, Sm, Yb) systematically decreases as a function of rare earth, consistent with the lanthanide contraction, except for YbCo2Al8, indicating a divalent Yb2+ state. LnCo2Al8 (Ln = Ce, Pr, Nd) show high temperature Curie–Weiss paramagnetism, and LnCo2Al8 (Ln = Pr, Nd) orders magnetically at TN = 5.6 and 8.7 K, with a fluctuating moment consistent with the trivalent oxidation state of the lanthanides. LnCo2Al8 (Ln = La–Nd, Sm, Yb) are metallic, with CeCo2Al8 having a residual resistivity ratio (RRR) of 20. We present the crystal growth, structural, magnetic, and electrical properties of single crystalline LnCo2Al8 (Ln = La–Nd, Sm, Yb).

In this report, the results of a study on the effects of compositional variations induced by the small changes in concentrations of the parent components and/or by the substitution of Ni, Mn, or In by an extra element Z, on the phase transitions, and phenomena related to the magnetostructural transitions in off-stoichiometric Ni–Mn–In based Heusler alloys are summarized. The crystal structures, phase transitions temperatures, and magnetic and magnetocaloric properties were analyzed for representative samples of the following systems (all near 15 at% indium concentration): Ni–Mn–In, Ni–Mn–In–Si, Ni–Mn–In–B, Ni–Mn–In–Cu, Ni–Mn–In–Cu–B, Ni–Mn–In–Fe, Ni–Mn–In–Ag, and Ni–Mn–In–Al.

To get complete knowledge about the evolution of different magnetic phases on application of temperature and magnetic field magnetic, magnetotransport and magnetocaloric properties of HoRu 2 Si 2 have been investigated from 2 to 100 K in magnetic fields ranging from 0 to 70 kOe in detail. The complex magnetic phase diagram of HoRu 2 Si 2 has been generated by studying magnetocaloric effect (MCE). Three ordered phases have been observed. With lowering of temperature in the presence of lower magnetic field ( 10 kOe ) two different types of ordered antiferromagnetic phases have been observed. Both of the phases show metamagnetic transition on application of external magnetic field greater than the required critical field. An efficient procedure to construct magnetic phase diagram using MCE has been described. The overlap of the data points obtained from the magnetization and magnetotransport data at the phase boundaries with those generated by MCE indicates the strength of this powerful technique.

In this report the magnetic behavior and magnetocaloric response of the intermetallic compound Dy5Pd2 has been investigated from detailed magnetization measurements. Magnetic cluster glass behavior has been observed in the crystalline Dy5Pd2 compound below 38 K. Magnetocaloric entropy changes evaluated using Maxwell’s relation (MXR) from zero-field-cooled magnetization isotherms, which is used mostly in the literature, shows a giant inverse magnetocaloric effect (MCE) below 20 K and a large conventional MCE around 60 K in this compound. The observed value of inverse MCE is ∼29 J kg−1 K−1 for 50 kOe external magnetic field change at T = 3.5 K. In this context, the origin of the giant inverse MCE and its temperature dependence has been studied. The applicability of MXR and procedure to obtain reversible MCE using MXR which is important for practical application has been discussed. Dy5Pd2 exhibits a reversible MCE with a peak value of magnetic entropy change (ΔSmaxM) 8.3 J kg−1 K−1 at 60 K under a magnetic field of 50 kOe and an irreversible inverse MCE below 20 K.

The crystal structure and magnetic properties of the R3Co29Ge4B10 (R = Ce, Pr, Nd, Sm, Gd, Dy) borides have been studied by X-ray powder diffraction (XRPD) and magnetization measurements. All compounds crystallize in a tetragonal crystal structure with the space group P4/nmm. Ferromagnetic behavior is observed for the R3Co29Ge4B10 compounds with light rare earth elements (Ce, Pr, Nd, Sm). The R3Co29Ge4B10 borides consisting of heavy rare earth elements (Gd, Dy) are ferrimagnets with the compensation temperatures of 120 and 82 K, respectively. The Curie temperatures are between 191 and 236 K.

Rural India still needs transitory advices on-demand as the infrastructures for health-care or similar essential services are still at a developing stage. Information and Communication Technologies (ICTs) can easily bring the needy rural population to the service providers and help in getting transitory advices effectively with some enhancements. In this paper, an enhanced ICT framework capable of video transmission at the text-transfer rate which may be deployed as a holistic effort for assisted local transitory help: an ICT deployment (HEALTH-AID) among the rural population is described.

Consider Bayesian variable selection in normal linear regression models based on Zellner’s $$g$$ -prior. We study theoretical properties of this method when the sample size $$n$$ grows and consider the cases when the number of regressors, $$p$$ is fixed and when it grows with $$n$$ . We first consider the situation where the true model is not in the model space and prove under mild conditions that the method is consistent and “loss efficient” in appropriate sense. We then consider the case when the true model is in the model space and prove that the posterior probability of the true model goes to one as $$n$$ goes to infinity. “Loss efficiency” is also proved in this situation. We give explicit conditions on the rate of growth of $$g$$ , possibly depending on that of $$p$$ as $$n$$ grows, for our results to hold. This helps in making recommendations for the choice of $$g$$ .

It has been found that Ni50Mn35In14B exhibits with increasing temperature a first-order magnetostructural phase transition from a low-magnetization martensitic phase to a high-temperature ferromagnetic austenitic phase at TM∼315 K as observed from magnetization M(T) curves with H=0.05 T. A shift in TM of about 12 K towards lower temperatures has been detected under application of a 5T magnetic field. An asymmetric magnetoresistance (spin-valve-like behavior) has been observed in the vicinity of TM at 304 K after the initial application of magnetic field that could be related to the kinetic arrest and de-arrest of a fractional austenite phase in the vicinity of phase co-existence. A possible origin of a spin-valve-like MR in Ni50Mn35In14B, and its relation to structural, magnetic, and magnetocaloric properties, has been discussed. (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

The studies of magnetocaloric properties, phase transitions, and phenomena related to magnetic heterogeneity in the vicinity of the martensitic transition (MT) in Ni–Mn–In and Ni–Mn–Ga off-stoichiometric Heusler alloys are summarized. The crystal structure, magnetocaloric effect (MCE), and magnetotransport properties were studied for the following alloys: Ni 50 Mn 50− x In x , Ni 50− x Co x Mn 35 In 15 , Ni 50 Mn 35− x Co x In 15 , Ni 50 Mn 35 In 14 Z (Z=Al, Ge), Ni 50 Mn 35 In 15− x Si x , Ni 50− x Co x Mn 25+ y Ga 25− y , and Ni 50– x Co x Mn 32− y FeyGa 18 . It was found that the magnetic entropy change, Δ S , associated with the inverse MCE in the vicinity of the temperature of the magneto-structural transition, TM, persists in a range of (125-5) J/(kg K) for a magnetic field change Δ H =5 T. The corresponding temperature varies with composition from 143 to 400 K. The MT in Ni 50 Mn 50− x In x ( x =13.5) results in a transition between two paramagnetic states. Associated with the paramagnetic austenite-paramagnetic martensite transition Δ S =24 J/(kg K) was detected for Δ H =5 T at T =350 K. The variation in composition of Ni 2 MnGa can drastically change the magnetic state of the martensitic phase below and in the vicinity of TM. The presence of the martensitic phase with magnetic moment much smaller than that in the austenitic phase above TM leads to the large inverse MCE in the Ni 42 Co 8 Mn 32− y FeyGa 18 system. The adiabatic change of temperature (Δ T ad ) in the vicinity of TC and TM of Ni 50 Mn 35 In 15 and Ni 50 Mn 35 In 14 Z (Z=Al, Ge) was found to be Δ T ad =−2 K and 2 K for Δ H =1.8 T, respectively. It was observed that |Δ T ad |≈1 K for Δ H =1 T for both types of transitions. The results on resistivity, magnetoresistance, Hall resistivity in some In-based alloys are discussed.

The crystal structure and magnetic properties of quaternary rare-earth intermetallic borides R 3 Co 29 Si 4 B 10 with R=La, Ce, Pr, Nd, Sm, Gd and Dy have been studied by X-ray powder diffraction and magnetization measurements. All compounds crystallize in a tetragonal crystal structure with the space group P 4/ nmm . Compounds with R=La, Ce, Pr, Nd and Sm are ferromagnets, while ferrimagnetic behavior is observed for R=Gd and Dy. The Curie temperatures vary between 149 K and 210 K. The Curie temperatures in R 3 Co 29 Si 4 B 10 (R=Ce, Pr, Nd, Sm, Gd, Dy) compounds are roughly proportional to the de Gennes factors.

(MnNiSi)1−x(FeCoGe)x undergoes a magnetostructural phase transition near room temperature that is acutely sensitive to applied hydrostatic pressure, which presents as a marked shift in the martensitic transition temperature (TM) by about –7.5 K/kbar. The magnetostructural transition can therefore be induced by applied hydrostatic pressure or by magnetic field. The barocaloric and magnetocaloric effects were measured across TM (for the sample with x = 0.38), and the corresponding entropy changes were +74 J/kg K (P = 2.7 kbar) and –58 J/kg K (μ0 H = 5 T), respectively. It was observed that the transition entropy change increases with pressure, which results in an enhancement of the barocaloric effect. Our measurements show that the transformed phase fraction associated with magnetostructural transition does not depend on pressure and, therefore, this enhancement cannot be attributed to a pressure-assisted completion of the phase transformation.

By means of alloying appropriate amounts of MnNiSi and MnFeGe, materials are found that undergo a paramagnetic to ferromagnetic transition close to room temperature, accompanied by a huge volume change. Thanks to this volume change, application of moderate pressures leads to a remarkable enhancement of the magnetocaloric response. Work like this may open new opportunities in the development of new solid-state magnetic refrigeration devices.

The magnetic properties, phase transitions, and related magnetocaloric effects in Mn1−xFexCoGe (x=0.12, 0.13) have been studied using magnetization and differential scanning calorimetry measurements. Instead of single first-order magnetostructural transition, two-step transitions have been detected in our studied system: one is second-order character followed by a first-order phase transition at lower temperature. The observed first-order phase transition as dominated by the crystallographic transition arises due to the coincidence of martensitic transformation with magnetic changes below the second-order magnetic phase transition in Mn1−xFexCoGe. Large magnetic entropy changes (−ΔSM) have been observed in our studied system due to a first-order phase transition between two high magnetization states. The estimated value of −ΔSM for x=0.12 (−ΔSM=16.5 J/kg K for ΔH=5 T around 242 K) is comparable to the giant-magnetocaloric materials, such as Gd5Si2Ge2 and MnFeP0.45As0.55, which undergo a disorder-to-order magnetostructural transition.

One way of handling composite hypotheses by SPRT's is to integrate out nuisance parameters under both the null and alternative hypotheses and then form an SPRT. If the prior is improper, Wald inequalities will not hold in general. We provide sufficient conditions and then verify that the usual sequential |t|-test satisfies these conditions but Wald's |t|-test does not satisfy these conditions and in fact cannot satisfy a strengthened form of these inequalities in general. Nonetheless, simulations show Wald's inequalities for A, B, corresponding to usual small α, β, will usually hold.

In a study with a therapeutic treatment, the patients may need to be prepared for the application of therapy when the earlier medications, if any, are withdrawn. This withdrawal period, known as adjustment period, may induce some worsening of condition in the patients. This paper investigates the risk of such worsening before the therapy is applied. We consider a number of possible models for this purpose and consider maximum likelihood estimation of the related parameters. Different concepts of risk, depending on the patients' concern, are introduced and thereby estimated using the parameter estimates. We finally analyse a data set on Rheumatoid Arthritis patients with Pulsed Electro-magnetic Therapy.

In Bayesian model selection, or hypothesis testing, difficulties arise when improper noninformative priors are used to calculate the Bayes factors. Several methods have been proposed to remove these difficulties. In this paper we discuss a unified derivation of some of these methods which shows that in some qualitative or conceptual sense, these methods are no more than a fixed number of observations away from a Bayes factor based on noninformative priors, and are close to each other and to certain Bayes factors based on low information proper priors which include priors recommended by Jeffreys (1961).

A geological map is the representation, on a two-dimensional plane, of the disposition of three-dimensional rock bodies exposed on the earth's surface. The problem of mapping is essentially that of dividing an area into “homogeneous” subregions on the basis of the exposed rock types. Automatic Bayesian methods of model selection using default Bayes factors have been employed to solve the problem of choosing a set of boundaries between “homogeneous” subregions, assuming no complication excepting low-angle tilting affected rock bodies. The method is tested on two data sets. A sampling scheme for optimum allocation of observation points is also presented.

We report the magnetic and magnetocaloric properties of the tetragonal rare-earth compound DyRu2Si2 under applied hydrostatic pressure. The isothermal entropy change ( ΔS) and the adiabatic temperature change ( ΔTad) were calculated from magnetization data collected at different applied pressures and from heat capacity measurements conducted at atmospheric pressure, respectively. The application of hydrostatic pressure significantly modified the multi-step magnetization curve and the saturation magnetization. A suppression of the magnetization was observed for P = 0.588 GPa and P = 0.654 GPa whereas, at about P ≈1 GPa, the saturation magnetization increased and the magnetization isotherms again resembled the curves measured at atmospheric pressure. A small thermal hysteresis was observed between the heating and cooling M(T) curves at Tt=3.4 K, with an applied magnetic field of H = 0.1 T. This thermal hysteresis indicates a first-order like transition which was also supported by the Arrott plot analysis. T...

A novel physical phenomenon has been observed that resembles a large asymmetric switchinglike magnetoresistance at low applied fields in bulk metamagnetic Heusler alloys. A thermally activated isothermal forward metamagnetic transition with a signature of a pronounced time-dependent relaxation was observed in a bulk B-substituted off-stoichiometric Ni-Mn-In Heusler alloy, whereas the reverse metamagnetic transition exhibited the usual athermal behavior with no thermal activation. The asymmetry between the forward and reverse metamagnetic transitions resulted in a large switchinglike, low-field magnetoresistance (\ensuremath{\sim}16% for a field change of $B$ = 0 \ensuremath{\rightarrow} 0.25 T at $T$ = 304 K) in the bulk Heusler alloys, ${\mathrm{Ni}}_{50}{\mathrm{Mn}}_{35}{\mathrm{In}}_{15\ensuremath{-}x}{\mathrm{B}}_{x}$ (1 \ensuremath{\leqslant} $x$ \ensuremath{\leqslant} 2).

We study the asymptotic behaviour of the posterior distributions for a one-parameter family of discontinuous densities. It is shown that a suitably centered and normalized posterior converges almost surely to an exponential limit in the total variation norm. Further, asymptotic expansions for the density, distribution function, moments and quantiles of the posterior are also obtained. It is to be noted that, in view of the results of Ghosh et al. (1994, Statistical Decision Theory and Related Topics V, 183-199, Springer, New York) and Ghosal et al. (1995, Ann. Statist., 23, 2145-2152), the nonregular cases considered here are essentially the only ones for which the posterior distributions converge. The results obtained here are also supported by a simulation experiment.

A comprehensive study of the temperature (T) and magneticfield (H) dependence of magnetic entropy change (�S M) for different materials exhibiting inverse magnetocaloric effect (IMCE) is reported. We show thatS M follows a power-law dependence of H (�S M ∼ H n ; n is an exponent) for these compounds. In contrast to conventional magnetocaloric effect (CMCE), n is independent of H and T in the case of IMCE. As a result, a universal master curve can be constructed to describeS M(T) of the IMCE systems for different H without rescaling the temperature axis. This is completely different from that reported for CMCE, where the rescaling of the temperature axis with the introduction of at least one reference temperature is needed for constructing a universal curve. The different universal behavior of IMCE is attributed to the constant value of n in any field and temperature, which is a generic feature of IMCE systems irrespective of their magnetic state and nature of phase transition. From the proposed phenomenological universal curve, one can extrapolate the magnetocaloric properties of IMCE systems in any temperature and magnetic field range, which would be helpful in designing controlled active magnetic refrigeration devices.

The magnetic, magnetotransport, and magnetocaloric properties near compound phase transitions in Ni50Mn35In14Z (Z = In, Ge, Al), and Ni48Co2Mn35In15 Heusler alloys have been studied using VSM and SQUID magnetometers (at magnetic fields (H) up to 5 T), four-probe method (at H = 0.005-1.5 T), and an adiabatic magnetocalorimeter (for H changes up to deltaH = 1.8 T), respectively. The martensitic transformation (MT) is accompanied by large magnetoresistance (up to 70%), a significant change in resistivity (up to 200%), and a sign reversal of the ordinary Hall effect coefficient, all related to a strong change in the electronic spectrum at the MT. The field dependences of the Hall resistance are complex in the vicinity of the MT, indicating a change in the relative concentrations of the austenite and martensite phases at strong fields. Negative and positive changes in adiabatic temperatures of about -2 K and +2 K have been observed in the vicinity of MT and Curie temperatures, respectively, for deltaH = 1.8 T.

The structural, magnetic, magnetocaloric, transport, and magnetoresistance properties of the rare-earth intermetallic compounds GdNi2Mnx (0.5 ≤ x ≤ 1.5) have been studied. The compounds with x = 0.5 and 0.6 crystallize in the cubic MgCu2 type phase, whereas samples with x ≥ 0.8 form a mixed MgCu2 and rhombohedral PuNi3 phase. A second order magnetic phase transition from a ferromagnetic to paramagnetic state was observed near the Curie temperature (TC). The GdNi2Mnx (0.5 ≤ x ≤ 1.5) compounds order in a ferrimagnetic structure in the ground state. The largest observed values of magnetic entropy changes (at TC for ΔH = 5T) were 3.9, 3.5, and 3.1 J/kg K for x = 0.5, 0.6, and 0.8, respectively. The respective relative values of the cooling power were 395, 483, and 220 J/kg. These values are greater than some well-known prototype magnetocaloric materials such as Gd (400 J/kg) and Gd5Si2Ge2 (240 J/kg). Analysis of the resistivity data showed a T2 dependence at low temperatures, suggesting strong electron-phonon...

The magnetic and magnetocaloric properties of intermetallic compound HoRu2Si2 have been investigated from experimental as well as theoretical point of view. Magnetization and magnetocaloric measurements on polycrystalline sample indicate an antiferromagnetic phase transition at 18 K. The theoretical investigation has done using a microscopic model and analyzed as a function of model parameters.

The enhancement of magnetoresistance (MR) has been observed in case of nanocrystalline La0.45Ca0.55MnO3 in comparison with its polycrystalline bulk form. It appears that the robust charge ordered state (COS) formed in bulk sample becomes unstable, when the sample is prepared in nanocrystalline form and can be destabilized in the presence of magnetic field giving rise to enormous MR.

Weak Paradoxes And Paradigms Nonparametrics in Modern Interdisciplinary Research: Some Perspectives and Prospectives Stepdown GERT Analysis of Consecutive-K Systems: An Overview Bounds on Distributions Involving Partial, Marginal and Conditional Information: The Consequences of Incomplete Prior Specification New Wrapped Distributions Non-Stationarity and Meta-Distribution Moment Bounds for Strong-Mixing Processes with Applications On Confidence Intervals for Expected Response in 2n Factorial Experiments with Exponentially Distributed Response Variables Non-parametric Estimation in a One-Way Error Component Model: A Monte-Carlo Analysis Predictive Influence of Variables in a Linear Regression Model When the Moment Matrix (X'X) is Singular Bayesian Curve Registration of Functional Data MDL Modeling Criterion for Linear Mixed Models Procedures Controlling a Generalized False Discovery Rate Digital Governance and Hotspot Geoinformatics with Continuous Fractional Response.

A study of the magnetocaloric effect has been performed on a polycrystalline CeRu(2)Ge(2) compound, which exhibits an antiferromagnetic ordering below T(N) = 8.3 K and enters into a ferromagnetic ground state at T(C) = 7.4 K. The origins of the magnetocaloric parameters (the isothermal entropy change: -ΔS and the adiabatic temperature change: ΔT(ad)) of the CeRu(2)Ge(2) compound below T(C) have been analyzed. A sharp decrease in -ΔS has been observed below T(C). However, the ΔT(ad) does not fall as sharply as -ΔS with decreasing temperature in the corresponding temperature region. This behavior results in an additional value of ΔT(ad) at low temperature, which originates from the exponential decrease of the magnetic contribution of specific heat associated with an increase of energy-gap in the ferromagnetic spin-wave spectrum with the application of magnetic field.

Recently the inverse magnetocaloric effect is observed for different compounds. However there is very rare for any manifestation of the effect to be seen in manganites. We have found inverse magnetocaloric effect in the case of polycrystalline La$_{0.125}$Ca$_{0.875}$MnO$_{3}$. Such phenomenon is attributed to the stabilization of antiferromagnetic state associated with inherent magnetic inhomogeneous phases for this compound., Comment: 3 Figures

Large low field magnetoresistance has been observed in the case of sol‐gel prepared nanocrystalline Pr0.65(Ca0.6Sr0.4)0.35MnO3 of average particle size ∼62 nm due to the melting of charge ordered insulating state. The system also shows large magnetocaloric effect at paramagnetic to ferromagnetic transition temperature. In the paramagnetic state, magnetoresistance and magnetic entropy change show similar magnetic field dependence.

The structural and magnetic properties of the Ni1−xCrxMnGe1.05 system (for x = 0, 0.035, 0.070, 0.105) have been studied by x-ray diffraction (XRD), differential scanning calorimetry (DSC), and magnetization measurements. A change in crystal structure from orthorhombic to hexagonal was observed in the XRD data at chromium concentrations of x = 0.035, 0.070, and 0.105. The values of the cell parameters and volume of the unit cell for orthorhombic and hexagonal phase were determined. It was found that the partial substitution of Cr for Ni in Ni1−xCrxMnGe1.05 results in a first order magnetostructural transition from antiferromagnetic to ferromagnetic (FM) at TM = 132 K for x = 0.105. A FM to paramagnetic second order transition has been observed at TC = 204 K. A magnetic entropy change of |ΔSM| = 4.5 J/kg K for ΔH = 5 T was observed in the vicinity of TC and TM for x = 0.105. The values of the latent heat (L = 2.2 J/g) and corresponding total entropy changes (ΔST = 16 J/kg K) have been determined from DSC m...

The structural, magnetocaloric, and thermomagnetic properties of Ni 50.51Mn34.34−xCuxIn14.14B1.01 with x = (0, 1.26, and 2.02) have been studied using room-temperature x-ray diffraction, differential scanning calorimetry (DSC), and magnetization measurements. The partial substitution of Cu for Mn was found to shift both the martensitic transition temperature (TM) and the Curie temperature (TC) to lower temperatures. The values of the latent heat (L = 9.4 J/g) and corresponding magnetic (ΔSM) and total entropy (ΔST) changes (ΔSM = 22.60 J/kg K for ΔH = 5 T and ΔST = 29.7 J/kg K) have been evaluated using magnetic and DSC measurements, respectively, for the sample with x = 1.26. Large negative values of ΔSM of −7.27 and −5.98 J/kg K for ΔH = 5 T in the vicinity of TC were observed for x = 1.26 and 2.02, respectively. It has been found that the application of hydrostatic pressure changes the magnetic ground state of the martensitic phase and increases the temperature stability of the martensitic phase. The roles of the magnetic and structural changes on the transition temperatures are discussed.

"This work was supported by the European Regional Development Fund (ERDF) through the Ireland Wales Programme (INTERREG 4A). DR acknowledges the support of the Russian Foundation for basic Research through grant 10-01-93112."

Resistivity, magnetoresistance, magnetization, and in-field heat capacity measurements were performed of the $\mathrm{Gd}{\mathrm{Pt}}_{2}$ intermetallic compound. The magnetocaloric parameters $\ensuremath{\Delta}{T}_{\mathit{ad}}$ and $\ensuremath{-}\ensuremath{\Delta}S$ were derived from in-field heat capacity data. Comparison has been made between the magnetocaloric effect $\ensuremath{-}\ensuremath{\Delta}S$ and difference in resistivity $\ensuremath{-}\ensuremath{\Delta}\ensuremath{\rho}\phantom{\rule{0.3em}{0ex}}[=\ensuremath{\rho}(H)\ensuremath{-}\ensuremath{\rho}(0)]$ as a function of temperature. There is distinct difference in the temperature dependence of $\ensuremath{-}\ensuremath{\Delta}S$ and $\ensuremath{-}\ensuremath{\Delta}\ensuremath{\rho}$ below the ferromagnetic transition temperature. However, after removing the domain wall contribution from $\ensuremath{-}\ensuremath{\Delta}\ensuremath{\rho}$, the natures of the $\ensuremath{-}\ensuremath{\Delta}S$ and $\ensuremath{-}\ensuremath{\Delta}\ensuremath{\rho}$ dependence as a function of temperature are similar. Our observation indicates that the domain wall contribution in the magnetocaloric effect is negligible in spite of the fact that it has a significant contribution in magnetotransport.

The magnetocaloric and thermomagnetic properties of Ni50Mn35(In1−xCrx)15 and (Mn1−xCrx) NiGe1.05 systems for 0 ≤ x ≤ 0.105 and 0 ≤ x ≤ 0.1, respectively, have been studied by x-ray diffraction, differential scanning calorimetry, and magnetization measurements. Partial substitution of Cr for Mn in (Mn1−xCrx)NiGe1.05 results in a first order magnetostructural transition from a hexagonal paramagnetic to an orthorhombic paramagnetic phase near TM ∼ 380 K (for x = 0.07). Partial substitution of Cr for In in Ni50Mn35(In1−xCrx)15 shifts the magnetostructural transition to a higher temperature (T = TM ∼ 450 K) for x = 0.1. Large magnetic entropy changes of ΔS = −12 (J/(kgK)) and ΔS = −11 (J/(kgK)), both for a magnetic field change of 5 T, were observed in the vicinity of TM for (Mn1−xCrx)NiGe1.05 and Ni50Mn35(In1−xCrx)15, respectively.