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The traditional high-efficiency absorber FeSiAl has gradually achieved the attention at high temperature. The paper focuses mainly on the preparation and characterization of plasma-sprayed FeSiAl coatings. The plasma-sprayed FeSiAl coatings were prepared through the Praxair 100HE high enthalpy plasma spray gun on stainless steel 316 substrate by orthogonal experiment. The cross-section and properties of sprayed coatings were analyzed. The results reveal that the best parameters of sprayed coatings can be represented by C3B2A3D2 for microhardness, i.e., 30 SCFH, 140 mm, 50 KW, 3 PRM. The optimal parameters can be expressed as C3D1B3A3 for adhesive strength, i.e., 30 SCFH, 2 PRM, 200 mm, 50KW. The cross-section of sprayed coatings is composed of fattening FeSiAl particles (pale gray) and oxidation phase of FeSiAl (dark). The percentage of disorder structure reduces in FeSiAl coatings.

Contributions of fermion loops, W-boson loops and their sum to the high energy γγ → γγ scattering total cross sections (|cosθ| < cos30°) are calculated by analytical expressions of γγ → γγ scattering amplitude. These contributions may be observed in the future photon linear collider and may be used to test standard model. The contribution of fermions' loops is a half of that in R.K. Arphlus and M. Neuuman's paper (Phys. Rev. 80 (1950) 380; 83 (1951) 776).

The analytic helicity amplitudes of Z → 3γ, γγ → γZ and γZ → γγ via W-loop and charged scalar-loop are presented. There is some difference between our results and those in Z. Phys. C60 (1993) 175 (E.W.N. Glover and A.G. Morgan) for Z → 3γ via W-loop and fermion-loop, which has different physical meanings.

The fourth rank polarization tensor and the helicity amplitudes of Z --> 3 gamma via charged Higgs boson loops in some nonstandard models with more than one Higgs doublet are calculated by using a nonlinear R(xi) gauge. The results are presented in terms of three transcendental functions of B(x), T(x) and I(x, y). We have checked the analytic results in Ref. [6] in comparison with ours.

The polarization tensors of Z → 3γ and γγ → γγ via W-Boson loops are calculated in the standard model. The constrained equations for the tensors are deduced from the crossing symmetry and gauge invariance. These equations are numerically checked by the polarization tensor of γγ → γγ to the first three lowest orders in its low energy expansion.

The contributions of the W loops to the decay of the Z into three photons and to the scattering of light by light are calculated. The C coefficients of the amplitudes of Z to 3 gamma and gamma gamma to gamma gamma* are shown. They are very useful for checking the authors earlier results.

The facile preparation of ZnO possessing high visible luminescence intensity remains challenging due to an unclear luminescence mechanism. Here, two basic approaches are proposed to enhance the luminescent intensity based on the theoretical analysis over surface defects. Based on the deduction, we introduce a methodology for obtaining hybrid tetrapod-like zinc oxide (T-ZnO), decorated by carbon nanomarterials on T-ZnO surfaces through the catalytic chemical vapor deposition approach. The intensity of the T-ZnO green emission can be modulated by topography and the proportion of carbon. Under proper experiment conditions, the carbon decorating leads to dramatically enhanced luminescence intensity of T-ZnO from 400 to 700 nm compared with no carbon decorated, which elevates this approach to a simple and effective method for the betterment of fluorescent materials in practical applications.

A new mechanism of gauge symmetry breaking is found which is induced by gravity in the SU(N) SUSY GUTS. The cosmological constant naturally vanishes, but the vacuum degeneracy cannot be removed at zero temperature.

In this note we list possible representations of the classical semisimple groups G1×G2 for finite N=2 supersymmetric Yang-Mills theories including the pseudoreal representations.

The authors list all possible representations of the semisimple groups SU(m1)*SU(m2)* . . . *SU(mk) for finite N=2 supersymmetric Yang-Mills theories.

The exact gauge coupling β function in the N-extended pure supersymmetric Yang-Mi11s (SYM) theories is extended to arbitrary gauge group and the exact β function in N=2 SYM theories with N=2 matter multiplets is obtained. Its vanishing in the latter cases is explicitly checked at two-loop level.

A systematic method for calculation of the minima of the potential in a simple supersymmetric SU(N) grand unified theory coupled to N=1 supergravity is presented. The method is essentially valid for more complicated cases of such theories.

In this note we obtain all two-loop finite N=1 supersymmetric Yang-Mills theories of real representations of SU(n) as well as those of complex representations. There are a few candidates which can accommodate three generations of quarks and leptons.

A whole class of two-loop finite N=1 supersymmetric Yang-Mills theories for all groups with the exception of SU(N) is obtained.

When electro-weak interactions are incorporated into Wess-Zumino-Witten effective action, the Cabibbo-like parameters automatically appear in the action. Applications of the action, to weak decays of pseudoscalar mesons are discussed.

A realistic finite grand unified model has to accomodate at least three generations of ordinary fermions. When this criterion is imposed, we found that only a few models of the SU( N ), SO(2 N ), SO(2 N +1) and exceptional groups can survive as candidates for possible realistic finite supersymmetric grand unified models. All possible solutions are obtained, but the SU(5) model is excluded.

Following Kaku's way, various interacting actions of bosonic open strings as well as closed strings are constructed, which are invariant under local reparametrization transformations, string group and global transformations of a Lie group. Similar to open string, a multiplication rule of closed string fields is given which also satisfies associative law as in open string case.

The authors list all possible representations of semisimple groups G=G1*G2*. . .*Gk (k>or=3) for finite N=2 supersymmetric Yang-Mills theories, but without consideration of the cases of pseudoreal representations.