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To develop the generic skills of students, colleges and universities are required to improve the curriculum to encourage students to engage proactively in learning and strengthening their competency to utilize acquired skills effectively in the society. However, no teaching methods as such have been established, especially, those of enhancing students’ competency. Competency is difficult to improve in a short period, therefore, continuous, effective approaches are needed. In this paper, based on the results of the continuous surveys, we present skills and competency of students which are required in the real world but show only low growth and need to be enhanced by the time they graduate from Kosen (five-year technical colleges in Japan), namely, planning, plan implementation and collaboration. Then we propose curriculum supplements and report on their effects. There are two points we attempted. First, to make students aware of the skills and competency to be improved, self-evaluation was performed before and after the course. Second, teachers tried to accelerate the progress of students’ skills by changing the way of conducting experiment classes. We report on the effects of these two points based on the evaluation by the students themselves.

The detailed BH loop measurements of an NiZn ferrite toroid have been studied at various temperatures below the Curie temperatures $T_{C}$ using a lock-in amplifier. The Jiles–Atherton (JA) analysis of the BH loops gives the power-law relations among the hysteresis parameters and the JA parameters. The Steinmetz analysis suggests the power-law relation proposed by Kobayashi et al. is valid in wide range of the temperature in low magnetic field.

The ac linear (X0) and nonlinear (X2) susceptibilities of an elemental ferromagnetic gadolinium have been studied at temperatures near the Curie temperature TC to clarify the feature of the magnetic phase transition, with special emphasis on the behavior at temperatures below TC. The temperature dependence of X0 is in good agreement with an experimental result reported in several references. The first observation for the critical behavior of X2 in gadolinium has been made at various field amplitudes. The behavior of nonlinear susceptibility is very sensitive to the field’s amplitude. The temperature dependence of X2 at temperatures below TC is not in agreement with some theoretical expectations and several experimental results for other ferromagnets.

This paper presents a hysteresis model to express magnetization curves as a function of field frequency, field amplitude, and temperature near Curie point $T_{\mathrm{C}}$ .

A new method is proposed to measure the magnetic hysteresis as a function of temperature. It is based on the spectral decomposition of magnetization and measurement of different harmonics using the harmonic-detection function of a lock-in amplifier. Applying this method, a measuring system of the BH loop was designed and fabricated. This system gives spectra of magnetic flux density B driven by an ac-magnetic field h. The BH loops are reconstructed from the spectra of the B. The spectra and BH loops were measured for a NiZn ferrite toroid at various temperatures. When the temperature increases from the room temperature, the higher harmonics of the spectra increase. Approaching the Curie temperature TC from below, magnetic loss and nonlinearity of the BH loops increase, and the loop shows the saturation just below TC.

An extensive study of electrical resistivity, ac magnetic susceptibility, magnetization, specific heat, and NMR has been made on high purity samples of the spinel compounds ${\mathrm{CuRh}}_{2}$${\mathrm{S}}_{4}$ and ${\mathrm{CuRh}}_{2}$${\mathrm{Se}}_{4}$. The superconducting transitions occur at 4.70 K in ${\mathrm{CuRh}}_{2}$${\mathrm{S}}_{4}$ and 3.48 K in ${\mathrm{CuRh}}_{2}$${\mathrm{Se}}_{4}$. The magnetic susceptibilities show perfect diamagnetism in both compounds. Upper critical fields at T=0 are estimated to be 20.0 and 4.40 kOe, the lower critical fields at T=0 are 70 and 95 Oe, respectively. The thermodynamic critical fields at T=0 are 704 Oe (${\mathrm{CuRh}}_{2}$${\mathrm{S}}_{4}$) and 445 Oe (${\mathrm{CuRh}}_{2}$${\mathrm{Se}}_{4}$). These values are obtained from the temperature dependence of the free energy. These compounds are type-II superconductors with Ginzburg-Landau parameters \ensuremath{\kappa}=21 (${\mathrm{CuRh}}_{2}$${\mathrm{S}}_{4}$) and \ensuremath{\kappa}=6.6 (${\mathrm{CuRh}}_{2}$${\mathrm{Se}}_{4}$) at T=0. The electron-phonon coupling constants, ${\ensuremath{\lambda}}_{\mathrm{ep}}$=0.68 (${\mathrm{CuRh}}_{2}$${\mathrm{S}}_{4}$) and ${\ensuremath{\lambda}}_{\mathrm{ep}}$=0.64 (${\mathrm{CuRh}}_{2}$${\mathrm{Se}}_{4}$), are obtained using the McMillan formula. The copper nuclear-spin-relaxation rate as a function of temperature shows a pronounced coherence peak just below ${\mathit{T}}_{\mathit{c}}$ for ${\mathrm{CuRh}}_{2}$${\mathrm{S}}_{4}$. Experimental results are analyzed on the basis of the BCS theory. These compounds exist between weak- and intermediate-coupling superconductors which are driven by electron-phonon interaction. The Debye temperatures FTHETA of these materials are 230 K (${\mathrm{CuRh}}_{2}$${\mathrm{S}}_{4}$) and 211 K (${\mathrm{CuRh}}_{2}$${\mathrm{Se}}_{4}$).

The ac linear (χ 0 ) and nonlinear (χ 2 ) susceptibilities of ferromagnetic fine cobalt particles, which were precipitated in a Cu 97 Co 3 alloy, have been studied. The χ 0 has a spin-glass-like maximum and χ 2 has a very broad negative peak at a low temperature. At high temperatures, the in-phase linear susceptibility χ 0 ' obeys the Curie law and the in-phase nonlinear susceptibility χ 2 ' is proportional to T -3 . A quantitative analysis of χ 0 and χ 2 based on a simplified superparamagnetic blocking model has been performed. The temperature dependence of the in-phase and out-of-phase susceptibilities is well described quantitatively by the superparamagnetic blocking model. It is concluded the behavior of χ 2 can be explained by the summation of the nonlinear term of the Langevin function over particle volume distribution. The analysis also yields information about the particle volume distribution and a value of anisotropy energy.

The field-cooled (FCM) and zero-field-cooled (ZFCM) magnetization of ferromagnetic fine cobalt particles in a Cu 97 Co 3 alloy has been studied. The spin-glass-like temperature dependence of the magnetization has been observed; ZFCM exhibits a spin-glass-like maximum (at T p ) and FCM is larger than ZFCM at low temperatures. However, the difference between FCM and ZFCM obviously exists far above T p . Furthermore, FCM increases monotonically with decreasing temperature even below T p while that of typical spin glasses is nearly independent of temperature. The analysis of the magnetization shows that the temperature dependence of FCM and ZFCM of Cu 97 Co 3 is well described on the basis of the superparamagnetic blocking model with no interaction between the particles, whereas that of a typical spin-glass Au 96 Fe 4 cannot be explained by the blocking model.

The ac linear (χ 0 ) and nonlinear (χ 2 ) susceptibilities of a ferromagnetic Ni have been studied near the Curie temperature, to clarify the feature of the magnetic phase transition. The first observation for the critical behavior of χ 2 in a pure ferromagnetic system has been made at low frequency measurement. The observed χ 2 at higher frequencies is affected extremely by the contribution of the eddy currents. From analysis of the frequency dependence of χ 0 and χ 2 , the method of eddy-current correction for χ 2 is found. Analysis of the critical behavior of χ 0 and χ 2 yields the critical exponents γ=1.333±0.008 and γ 2 =4.69±0.30.

The ac linear (χ 0 ) and nonlinear (χ 2 ) susceptibilities of Au 82 Fe 18 alloy have been studied around the Curie temperature T c , to make clear the feature of the magnetic phase transition. In very low field measurements, the nonlinear susceptibility χ 2 is observed only in the vicinity of T c and the temperature dependence of χ 2 is in good agreement with theoretical expectations in the transition from a ferromagnetic phase to a paramagnetic phase. Analysis of the critical behavior of χ 0 and χ 2 yields the susceptibility exponent γ=1.33 ±0.05 and the nonlinear susceptibility exponent γ 2 =4.82 ±0.50. These values are very close to theoretical predictions for 3d-Heisenberg pure ferromagnets.

The ac linear (χ 0 ) and nonlinear (χ 2 ) susceptibilities of ferromagnetic fine cobalt particles, which were precipitated in a Cu 97 Co 3 alloy, have been studied. The linear susceptibility χ 0 has a spin-glass-like maximum at low temperature. The nonlinear susceptibility χ 2 is negative and has a peak around the temperature where χ 0 exhibits the maximum. However, the negative peak in χ 2 is very broad compared with that of spin glasses. Furthermore, χ 2 is proportional to T -3 at high temperatures. This behavior of χ 2 in the Cu 97 Co 3 alloy is essentially different from the divergent behavior of χ 2 in spin glasses.