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The Confucian understanding of emotions and their ethical importance confirms and exemplifies the contemporary Western renewed understanding of the nature of emotions. By virtue of a systematic conceptual analysis of Confucian ethics, one can see that, according to Confucians, the ethical significance of emotions, lies in that an ethical life is also emotional and virtues are inclinational. And a further exploration shows that the reason for the ethical significance is both that emotions are heavenly-endowed and that there exists a union of emotions and reason in Confucian ethics. This will constitute a challenge to the so-called mainstream ethical theories which have been popularly engaged in seeking justifications for abstract moral rules.

The field-tuned ac susceptibility of Mn12Ac single crystal has been measured as functions of temperature and frequency. Two relaxation processes appear in our measurement. One is related to the magnetic quantum tunnelling of a collective spin S = 12 by a 61 K magnetic barrier and it has been well studied, while the other is faster than the former and its mechanism is unclear. We find that the relaxation time for the faster process shows the minima at H = 0 and H = 3.4 kOe, indicating that the quantum tunnelling also takes place in this process while the resonant fields are different from what we have known before.

Tunneling spectroscopy of Al73Ni17Co10 decagonal single quasicrystals has been measured at ultralow temperatures. In addition to the wide pseudogap observed in previous photoemission experiments. very rich fine structures in the density of states around the Fermi energy were discovered. The fine structures strongly depend on the applied magnetic field and disappear above similar to 4 T. The zero-bias resistance of the junction varies with magnetic fields in a complicated way, which is suggested to be related to the hierarchy structure of quasicrystals. A puzzling hysteretic phenomenon was observed in some bias ranges in zero magnetic field, the origin of which needs to be clarified in the future. [S0031-9007(99)08419-7].

We report the discovery that the low-temperature magnetic relaxation in Mn(12)Ac single crystals strongly depends on the shape of the samples. The relaxation time exhibits a minimum at the phase transition point between ferromagnetic and antiferromagnetic phases. The shape dependence is attributed to the dipolar interaction between molecular magnets.

The charge density wave gaps of NbSe 3 have been carefully determinated by tunneling spectroscopy. In contrast to earlier work, the gap parameter associated with the 59 K transition obtained in the present measurements is very close to the mean field value. The gap structures for both the 145 K and 59 K transitions are found to be essentially independent of the applied magnetic field H. The present findings strongly suggest that the anomalous magnetotransport properties of the material originate from some other mechanism than a H-induced improvement of Fermi surface nesting.

The Hall effect of YBa 2 Cu 3 O 7-δ epitaxial films in the vicinity of superconducting transition was studied under ultra low magnetic fields down to 10-3 T where some field-induced extrinsic effects, such as the reduction and broadening of the transition temperature and the enhancement of fluctuation, can be neglected. The Hall sign reversal was still observed down to the lowest field we arrived, which shows that any mechanism connected with above mentioned extrinsic changes cannot be responsible for the effect. The Hall resistivity ρxy, Hall angle tan α and Hall conductivity σxy are all simply proportional to the magnetic field, resembling the behaviors of the ordinary Hall effect in the low-magnetic-field limit. The temperature range with observable negative Hall resistivity coincides with the critical fluctuation region. These behaviors shows that the negative Hall effect cannot be understood in the picture of flux flow.

Here a direct calculation of the dipolar interaction in a single crystal Mn12, with all of Mn ions summed, shows that a transition between a ferromagnetic ground state and an antiferromagnetic ground state takes place where the dimension along the a(b) axis versus the dimension along the c axis reaches a certain critical value. It is shown that the ground state is dependent upon the shape of the specimen. The reason of the shape dependence of ordering is that dipolar interaction is of long-range nature and the sign of dipolar interaction is dependent on the direction.

It is shown that when the wave packet of a photon passes through a region where more than one path mode can be chosen, the interference between these modes of the probability waves of the photon causes a reshaping process of the wave packet. In some conditions this reshaping gives rise to an apparent superluminal traveling, as observed by Steinberg, Kwiat, and Chiao [Phys. Rev. Lett. 71, 708 (1993)]. The present model also leads to some predictions that can be tested experimentally.

The temperature T dependence of the resistivity of decagonal single quasicrystals available at present has been carefully examined from 77 to 340 K. All the samples show a precisely linear T dependence of resistivity along the periodic direction, while in the quasicrystalline plane a quadratic term was added to fit the data. The linear T dependence in the large temperature range implies a very low transport Debye temperature, and can be easily understood by the nearly filled band model used to explain Hall-effect anisotropy. The T dependence of the resistivity in the quasicrystalline plane can be satisfactorily explained by the generalized Faber-Ziman theory, proving an enhanced electron-phonon interaction and an enhanced phonon-phonon coupling in the quasicrystalline plane.

A method for measuring flicker noise down to very low frequencies is described. We have used the method to measure 1/ f noise in a bulk sample of Al 65 Ni 20 C 15 2D quasicrystals rather than the thin metallic films that are generally used for such measurements. Preliminary results show that flicker noise in the quasicrystalline plane can be well cataloged into the behavior of an ordinary metal.

The anisotropic thermal conductivity of Al65Ni20Co15 and Al62Si3Cu20Co15 single quasicrystals has been measured. While a nearly isotropic phonon contribution was observed, the electronic thermal conductivity is almost completely suppressed in the quasicrystalline plane in contrast to the periodic direction where the materials behave like the usual 3D alloy except for a markedly lower electronic contribution.

Careful studies on single decagonal quasicrystals show that the anisotropy of the Hall coefficient R(H) is quite universal for these structures. R(H) changes sign when the magnetic field rotates by 90-degrees from the tenfold axis. In both cases, R(H) depends weakly on the temperature T between 80-330 K. All the single quasicrystals (Al-Ni-Co, Al-Cu-Co, and Al-Si-Cu-Co) have actual compositions which lead to a definite average valence-electron number, in spite of the nominal compositions, indicating the formation of the decagonal phase confined in a narrow composition range by the strong interaction of the Fermi surface with the quasi-Brillouin zone.

In the American Institute of Steel Construction (AISC) LRFD specification, the shear lag coefficient for plate members is dependent on only the ratio of the welding length to the plate width. To determine how this ratio influences the shear lag coefficient and whether there are other factors that should be considered, a finite element investigation was conducted. Experimental data from a previous study conducted at Virginia Tech was used for comparison with the analytical model. Upon completion of the verification study, several parameters were investigated to determine their influence on the shear lag coefficient. These included the effects of weld length, eccentric load and imperfection created by the welding process. Shear lag coefficients were determined from the finite element analyses and compared with the AISC specification values. Master of Science

The ac susceptibility of single crystals of Ni-4 single-molecule magnets is measured by a compensation measurement setup. The magnetic relaxation time calculated from the peak of the out-phase component of the susceptibility fits the Arrhenius law well and gives an effective spin-flipping energy barrier of U-eff = 7.2 K. This value is far below the classical activation energy barrier of.. = 14 K, whereas it is close to the energy gap between the S-z - +/- 4 and S-z - +/- 3 doublets, which indicates that quantum tunneling between the S-z - 3 and S-z - -3 states plays a key role in the magnetic relaxation. Therefore the relaxation process combines thermal activation and quantum tunneling. Also we deduce that the blocking temperature of Ni-4 single-molecule magnets is lower than 0.3 K by extrapolating the relaxation time plot, which ensures that this single-molecule magnet material enters a long-range magnetic ordered state instead of a spin glass state at 0.91 K.

The thermal stability of Mn12-Ac[Mn12(CH3COO)16(H2O)4O12]52CH3COOH54H2O magnetic molecular crystals was investigated by TG-DTA from room temperature to 270℃. According to the results of XRD and TG,we found that Mn12-Ac lost the crystal water and the acetic acid molecules of solvation which were located between the adjacent molecules in the temperature range from 25℃ to 1 10℃. At the same time, 4H2O which were linked with 4 Mn3+ were lost. The crystalline structure of Mn12-Ac single crystal was destroyed during this course. However, the core structure in the molecule was well preserved. From 180℃ to 230℃, a further transformatio n took place, Mn12-Ac lost all the CH3COO- ions and turned intoγ-Mn2O3, with a little amount of Mn3O4.