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Deinococcus radiodurans (D. radiodurans) is an extremophile that can tolerate ionizing radiation, ultraviolet radiation, and oxidation. How D. radiodurans responds to and survives high levels of ionizing radiation is still not clear. In this study, we performed label-free proteomics to explore the proteome dynamics during postirradiation recovery (PIR). Surprisingly, proteins involved in translation were repressed during the initial hours of PIR. D. radiodurans also showed enhanced DNA repair and antioxidative response after 6 kGy of gamma irradiation. Moreover, proteins involved in sulfur metabolism and phenylalanine metabolism were enriched at 1 h and 12 h, respectively, indicating different energy and material needs during PIR. Furthermore, based on these findings, we proposed a novel model to elucidate the possible molecular mechanisms of robust radioresistance in D. radiodurans, which may serve as a reference for future radiation repair.

Graded refractive index media (GRIM) are widely applied as special functional materials in many practical engineering fields. Accurate knowledge of the optical parameters is key to using GRIM. In this study, simultaneous reconstruction of the refractive index and absorption coefficient fields of GRIM based on laser beam deflection and attenuation measurement is studied. A set of rays from the given positions along the given directions transits GRIM, and the deflection and attenuation of rays at the exit boundary are recorded as measurement information. A two-step reconstruction strategy is proposed to reconstruct the refractive index and absorption coefficient fields. First, the refractive index field is reconstructed from the ray deflection measurement information. Then, the ray trajectory can be obtained by the Runge–Kutta ray tracing technique based on the reconstructed refractive index field. Afterwards, the absorption coefficient field is reconstructed from the ray attenuation measurement according to the Bouguer law. The regularization technique based on the generalized Gaussian Markov random field model is employed to improve the reconstruction results. All test results show that the two-step reconstruction strategy is accurate and can be regarded as a promising reconstruction technique.

Paraffin as an organic phase change material with high latent heat and stable physical and chemical properties, is widely used as building filling materials to absorb and store solar energy. And the spectral properties of paraffin is crucial to study the phase change characteristics of paraffin materials in absorbing solar energy. Therefore, this work studies theoretically the inverse identification of spectral properties of paraffin phase change materials. A multi-thickness model is developed to determine the optical constants (spectral refractive index and absorption index) of paraffin materials in solid and liquid state based on transmittance data. This model overcomes ill-posed and multiple solution of inverse problems. An improved quantum particle swarm optimization algorithm is adopted to determine spectral refractive index and absorption index of paraffin materials with high accuracy. A serious of numerical experiments are implement to study retrieval problems thoroughly and results show that the inverse strategy we develop is a promising technique to obtain spectral properties of paraffin materials.

The generalized source term multiflux method (GSMFM) combined with Runge-Kutta ray tracing technique is developed to calculate arbitrary directional radiative intensity of graded-index media. In this method, the finite volume method is employed to solve source terms along the curved ray path determined by the Fermat principle. Runge-Kutta ray tracing technique is adopted to obtain the ray trajectory numerical solution in graded-index media. And the GSMFM is used to solve radiative intensity to be expected. One-dimensional and two-dimensional radiative heat transfer problems are investigated to verify the performance of this method. The numerical results show that the accuracy of the GSMFM is close to that of backward Monte Carlo (BMC) method, while the efficiency of GSMFM is much higher than that of the BMC. Therefore, the GSMFM developed can be considered as a promising method to solve arbitrary radiative intensity in graded-index media.

Beam blank reheating is a key process in the production of high-quality H-beam. To gain better insight into the heat transfer process of the beam blank in reheating furnace, a heat transfer model considering radiative heat transfer of furnace gas and conductive heat transfer in beam blank simultaneously is established. The main variable-correction method and zonal method are adopted to solve heat transfer problems in reheating furnace. The best productivity point (BPP) and optimal productivity range (OPR) of the reheating furnace based on the relationship between the specific heat consumption and furnace efficiency are firstly proposed to guide the production process. Then, the effects of the length of soaking zone and preheating temperature of air and fuel on thermal characteristics of walking reheating furnace for beam blank are analyzed. The results show that the reasonable length of soaking zone can obtain high reheating quality of the beam blank, reasonable temperature of furnace gas and exhaust gas. The preheating air has a more influence than preheating fuel on the reheating process of reheating furnace for beam blank. This work can provide valuable reference for the determination to make thermal schedule of beam blank and on-line supervisory control of the production process.

Refractive index as one of the most important optical properties of materials is the key to utilize refractive index elements. However, it is very difficult to measure or estimate refractive index of media, especially for multi-dimensional inhomogeneous refractive index distribution. Therefore, an inverse scheme is presented for reconstructing refractive index field in rectangular gradient index medium based on ray deflection measurement in this work. A collection of rays from given positions along given directions transit the semitransparent medium and all exit boundary positions are recorded to construct the objective function of inverse problem. Runge–Kutta ray tracing technique is employed to simulate the curved ray path determined by Fermat principle in gradient-index medium. Conjugate gradient method as an inverse algorithm is used to reconstruct refractive index field. A series of simulation experiments are done to show the performance of the inverse strategy we developed. The results indicate that this inverse strategy for reconstructing refractive index field is accurate and effective.

Inverse estimation of temperature-dependent refractive index and absorption coefficient of semitransparent media is studied in this work. The forward transient coupled radiation-conduction heat transfer in semitransparent media is simulated by the finite volume method. The time-varying radiative response signals at the boundary (not the laser irradiation boundary) is adopted as measurement information in the inverse model. An improved teaching-learning-based optimization (ITLBO) algorithm is developed to retrieve the temperature-dependent refractive index and absorption coefficient simultaneously. Effects of model parameters (i.e. the laser heating time and measurement errors) and thermophysical parameters (i.e. the thermal conductivity and heat capacity) on the estimated results are analyzed thoroughly. All the retrieval results show that the inverse model and inverse algorithm is accurate and effective for predicting the temperature-dependent radiative properties of semitransparent media.