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In this study, neutron-emission spectra produced by (n,xn) reactions on nuclei ²³²Th have been calculated. Angle-integrated cross-sections in neutron induced reactions on targets ²³²Th have been calculated at the bombarding energies from 2 MeV to 18 MeV. We have investigated multiple pre-equilibrium matrix element constant from internal transition for ²³²Th(n,xn) neutron emission spectra. In the calculations, the geometry dependent hybrid model and the cascade exciton model including the effects of pre-equilibrium have been used. Pre-equilibrium direct effects have been examined by using full exciton model. In addition, we have described how multiple pre-equilibrium emissions can be included in the Feshbach–Kerman–Koonin (FKK) fully quantum-mechanical theory. By analyzing (n,xn) reaction on ²³²Th, with the incident energy from 2 MeV to 18 MeV, the importance of multiple pre-equilibrium emission can be seen clearly. All calculated results have been compared with experimental data. The obtained results have been discussed and compared with the available experimental data and found agreement with each other.

The behavior of a Dirac field in a Schwarzschild black hole spacetime is studied. In this work the Hawking temperature and the absorption cross-section for Schwarzschild black hole placed in Dirac field are calculated, taking into consideration the matter waves reflected from the event horizon. The absorption cross-section σ_abs in Dirac field is found to be ⅛ of absorption cross-section in scalar field. The emission spectra of Schwarzschild black hole placed in an environment of Dirac field is also obtained.

In this brief review, we discuss the viability of a multi-dimensional geometrical theory with one compactified dimension. We discuss the case of a Kaluza–Klein (KK) fifth-dimensional theory, addressing the problem by an overview of the astrophysical phenomenology associated with this five-dimensional (5D) theory. By comparing the predictions of our model with the features of the ordinary (four-dimensional (4D)) Relativistic Astrophysics, we highlight some small but finite discrepancies, expectably detectible from the observations. We consider a class of static, vacuum solutions of free electromagnetic KK equations with three-dimensional (3D) spherical symmetry. We explore the stability of the particle dynamics in these spacetimes, the construction of self-gravitating stellar models and the emission spectrum generated by a charged particle falling on this stellar object. The matter dynamics in these geometries has been treated by a multipole approach adapted to the geometric theory with a compactified dimension.

Nitrogen oxides exhaust gas assumes the important responsibility on air pollution by forming acid rain. This paper discusses the NO removal mechanism in 15 ns pulse dielectric barrier discharge (DBD) plasma through experimental and simulating method. Emission spectra collected from plasma are evaluated as sourced from N⁺ and O(³P). The corresponding zero-dimensional model is established and verified through comparing the simulated concentration evolution and the experimental time-resolved spectra of N⁺. The electron impact ionization plays major role on NO removal and the produced NO⁺ are further decomposed into N⁺ and O(³P) through electron impact dissociative excitation rather than the usual reported dissociative recombination process. Simulation also indicates that the removal process can be accelerated by NO inputted at lower initial concentration or electrons streamed at higher concentration, due to the heightened electron impact probability on NO molecules. The repetitive pulse discharge is a benefit for improving the NO removal efficiency by effectively utilizing the radicals generated from the previous pulse under the condition that the pulse period should be shorter enough to ignore the spatial diffusion of radicals. Finally, slight attenuation on NO removal has been experimentally and simulatively observed after N₂ mixed, due to the competitive consumption of electrons.

Two methods used for microtube temperature calculation through outer microtube emission spectra are presented. The emission spectra of microtube flame and the outer flame are measured by a CCD fiber spectrometer in the same environment, and the outer flame temperature is measured by thermocouple simultaneity. Outer microtube flame spectra act as referenced spectra. In the first method, spectra correction coefficients are calculated with some wavelengths of referenced spectra. With the functional relationship between the wavelength and the emissivity in the referenced spectra, microtube flame temperature is computed from the emission spectra in the other method. The flame temperature is calculated by the methods on the spectra measurement data.

Spectral properties of metallophthalocyanines and other tetraazaporphyrins are governed mainly by the Q band which originates from the π-π* transitions within the ring. The position and intensity of the Q band is important in tailoring new phthalocyanine derivatives for particular applications. Aggregation, the nature of the central metal, π conjugation, symmetry of the molecules, and axial, peripheral or non-peripheral substitutions affect the spectra and hence the properties of the phthalocyanine molecule. This review gives a brief outline on how optical spectroscopy provides useful informations on molecular and electronic structures, chemistry and physics of phthalocyanines and other tetraazaporphyrins.