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Bonding has been used to repair carbon fiber-reinforced polymer (CFRP) materials. However, research has shown that resin residue on the surface of CFRP can cause adhesion problems. Therefore, a reliable surface cleaning procedure is necessary to remove the resin residue before bonding. In this paper, the surface resin was removed by laser cleaning, while the surface properties of CFRP were improved. A pulsed laser cleaning experiment was designed to study the chemical activity and bonding strength of CFRP treated by laser with different laser power and scanning speed. The results showed that as the contact angle of the material surface decreased, chemical activity and adhesive properties were improved. The surface pretreated with laser power of 16 W (scanning speed of 1500 mm/s) had no resin residue and the best adhesive properties; the bonding strength was 1.6 times higher than that of the untreated surface, and the failure mode was dominated by a cohesive damage mode.Based on the randomness of spontaneous emission, the statistical characteristics of phase noise are discussed. A theoretical analysis model, focusing on the amplitude randomness of spontaneous emission, is established to calculate laser phase noise. Then, the coherence of a laser before and after phase-locked control is calculated when an ideal laser and nonideal laser are used as a reference light in an optical phase-locked loop (OPLL). The effects of the amplitude randomness of spontaneous emission on phase-locked laser coherence are analyzed in detail. The results show that phase noise randomness increases with the increase of the expectation or variance of spontaneous emission amplitude, which represents amplitude randomness. When an ideal light is used as reference light, if the expectation and the variance of spontaneous emission amplitude are about 10 and 100, respectively, the time constant of an OPLL should be set as 1 ns, while a favorable noise suppression result can be achieved. Bcl-2 apoptosis pathway However, to achieve a favorable noise suppression result, the time constant of an OPLL should be set as 0.1 ns when a nonideal laser is used as reference light.In this paper, we propose a broadband omnidirectional near-perfect absorber that transforms light energy into heat. In contrast to previous research on structural metamaterials, this study focuses on light absorption in the epsilon-near-zero (ENZ) layers without any structural patterns. Chromium (Cr) thin films were applied as ENZ layers. Using the admittance method, we found the proper thicknesses of SiO2 layers to match the incident medium and achieve perfect absorption. Also, the absorber is angular insensitive up to 60°. The temperature of the absorber increases from room temperature to 42°C, which is 4°C higher than the uncoated substrate at 38°C, after exposure to sunlight for 20 min.In this work, we study the effects of noise present on spectral interferometry signals, for femtosecond pulse retrieval such as in the SPIDER technique (spectral phase interferometry for direct e-field reconstruction). Although previous works report SPIDER robustness, we have found that noisy signals with low signal-to-noise ratio (SNR), in the acquired spectral interferogram, could cause variations in the temporal pulse intensity retrieval. We demonstrate that even in a filtered SPIDER signal, following standard procedures, at some point the noise on the spectral interferogram could affect the spectral phase retrieval. As a novel alternative for spectral interferograms filtering, we have applied the wavelet transform and propose a target criterion to automatize the optimization algorithm. We apply this method on SPIDER signals and analyze its effectiveness on the spectral phase retrieval. We present numerical and experimental results to show the improvement in the phase retrieval and the temporal pulse reconstruction after applying this filtering method and compare the results with a standard method.A developed three-dimensional finite element model to describe surface profiles and root mean square (RMS) roughness by pulsed laser polishing based on the melting flow and vaporization removal mechanism is innovatively presented. In this paper, we indicate that the melting flow and vaporization removal are the primary mechanisms in the laser polishing process and successfully simulated the S316 mold steel pulsed laser polishing via the finite element method. Notably, vaporization removal, vaporization expansion, and plasma impact pressure, which is based on the Navier-Stokes equation, continuity equation, and Marangoni effects, are crucial factors, which are creatively taken into account in this model. Besides, due to the physical parameters changing with temperature, it is critical to considering the temperature-dependent density, specific heat capacity, thermal conductivity coefficient, dynamic viscosity, and tension coefficient to make the simulation results and model accurately. In addition, the tailored model can predict the theoretical polishing surface profiles and RMS roughness based on the melting flow and vaporization removal mechanism. Regarding the single pulse laser polishing, we investigated the surface profiles and RMS roughness on different single pulse energy and pulse width. In summary, it is expected that this study could provide a theoretical reference regarding the laser polishing metals and pave the way for laser manufacturing in various industrial applications.The nonorthogonal shaft laser theodolite (N-theodolite) measurement system is a new kind of instrument that can be applied to large-scale metrology. Different from traditional theodolites, the three axes of the N-theodolite have no requirements on the orthogonality and intersection. For the measurement in laser scale, the parameters of the system on a large scale must be known. A calibration method of the laser beam based on specular reflection and its compensation are proposed, which are at a range of 12 m. Through the experiments, the results show that the straightness accuracy of the laser beam of the left N-theodolite is 0.12 mm at a range of 12 m, and the right one is 0.14 mm. Through the measurement experiments, the maximum measurement deviation of the system is 0.27 mm, which is verified to be a feasible method to calibrate the laser beam in large-scale space.