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This study proposes a novel approach to surface strain measurement for cylindrical rock specimens subjected to uniaxial compression using distributed fibre optic sensing technology. The capability and accuracy of this approach in measuring the full-field strain distribution of a rock specimen have been verified by a series of uniaxial compressive strength (UCS) tests on cylindrical specimens of aluminium alloy, sandstone, and granite. By analysing the experimental results, this new approach also has the potential of being utilized to detect the potential failure locations and sequence through strain localization zone variations and estimation of the development of crack opening displacement and rock fracturing characteristics during the loading and unloading process. Detailed installation procedures are provided for this study for assistance in the use of this new approach. The boundary issue of fibre measurements is identified, and solved by extending the bonding length of the measuring fibre.

Aiming at the problems of high water cuts in the later stages of multi-throughput and the inability to effectively develop the remaining oil between wells in ordinary heavy oil reservoirs. The development of block flood control and viscosity reduction complex flooding was proposed, in which the flood control agent can achieve the blocking and deep regulation of high permeability channels. Dissection, effectively expanding the volume of subsequent viscosity reducing agents. Through a large number of preferred evaluations, a polymer with viscosity-increasing properties for certain mineral formation water salinity, low viscosity at injection temperature, and high viscosity at the bottom hole temperature (65 ° C) was selected, and other properties of the polymer were tested. The results show that the polymer is hydrophobically associative and has temperature-sensitive properties. As the temperature increases, the polymer viscosity first increases and then decreases. At the reservoir temperature, the maximum viscosity of 3000 mg/L polymer reaches 919 mPa.s; The polymer also has excellent anti-aging properties and shear resistance. After storage at the reservoir temperature (65 °C) under anaerobic conditions for 90 days, the viscosity retention rate reaches 97%; In the shear force of the reservoir (7.5 s−1) conditions, the viscosity of the polymer will not decrease due to multiple shears. The displacement effect of 1# polymer was verified by the dual-tube high-low-permeability mold displacement experiment. The results show that the polymer can effectively block the high-permeability layer and effectively use the low-permeability layer.

The La0.7SrxCa0.3-xMnO3 (x=0, 0.05, 0.1, 0.15, 0.2, 0.25 and 0.3) were prepared by combining sol-gel method and high temperature sintering. The effects of Sr doping content on the structure and morphologies of the La0.7SrxCa0.3-xMnO3 finally sintered at 1050°C/1250°C were investigated based on the analyses of X-ray diffraction (XRD) and Scanning Electron Microscope (SEM). The results show that the La0.7SrxCa0.3-xMnO3 exhibit single perovskite phase and the change of Sr doping content can result in phase structure transition. The La0.7SrxCa0.3-xMnO3 samples are rhombohedra structure in the range of 0.15≤x≤0.3. When x is no more than 0.1, the La0.7SrxCa0.3-xMnO3 samples sintered at 1050°C present distorted cubic structure. The microstructure of La0.7SrxCa0.3-xMnO3 sintered at 1050°C for 5h becomes more and more looser and its grains tend to refinement with the increase of Sr doping content when x is no less than 0.05. Increasing the final sintering temperature can improve the density and promote the grain growth of La0.7SrxCa0.3-xMnO3. In order to gain a dense microstructure, the final sintering temperature of La0.7SrxCa0.3-xMnO3 should be higher than 1050°C and should be suitably increased with the increase of Sr doping content.

The La0.8SrxCa0.2-xMnO3 (x=0, 0.05 and 0.15) compounds were synthesized by combining sol-gel method and high temperature sintering. The effects of Sr doping content on the microstructure, metal-insulator transition and magnetoresistance (MR) of the La0.8SrxCa0.2-xMnO3 were investigated. The results show that the La0.8SrxCa0.2-xMnO3 exhibit single perovskite phase and the change of Sr doping content can result in phase structure transition. The La0.8Sr0.15Ca0.05MnO3 is rhombohedra structure and the La0.8SrxCa0.2-xMnO3 shows distorted cubic structure when x is no more than 0.05. Increasing Sr doping content causes the degeneration of microstructure homogeneity and density and the decrease of average grain size of the La0.8SrxCa0.2-xMnO3, which can be attributed to the weakening of atomic diffusion during the sintering process. The metal-insulator transition temperature (TMI) of the compounds increases with the decrease of Sr doping content due to the improvement of microstructure. The La0.8Sr0.15Ca0.05MnO3 has the highest MR peak value, which is about 95%. The La0.8Ca0.2MnO3 has the highest room temperature MR, which is about 28%. Moreover, the magnetoresistance of the La0.8Ca0.2MnO3 is very stable between 125~300K.

The La0.7M0.3MnO3(M=Ca, Sr) were synthesized by combining sol-gel technique and solid state sintering method. The evolutions of phase structure and micro-morphologies of the La0.7M0.3MnO3with final sintering temperature (950-1250°C) were investigated. The results show that the La0.7Ca0.3MnO3compounds exhibit single perovskite phase with cubic structure and the La0.7Sr0.3MnO3compounds exhibit single perovskite phase with rhombohedra structure. The final sintering temperature has no obvious effect on the phase structure of La0.7Ca0.3MnO3. However, the density and grain size of La0.7M0.3MnO3(M=Ca, Sr) increase with the increase of the final sintering temperature. Moreover, the micro-morphologies of La0.7Ca0.3MnO3are more sensitive to final sintering temperature compared with that of La0.7Sr0.3MnO3. When sintering temperature is no less than 1150°C, the La0.7Ca0.3MnO3has hardly any pore. After sintering at no less than 1250°C, the La0.7Sr0.3MnO3becomes dense.

Silk fibroin film (SFF) has good mechanical property, cells compatibility and biodegradability, and was widely used in the biomedical area as controlling materials. In this work, silk fibroin (SF) was obtained from cocoons. It was dissolved in distilled water to form 5 % and 8 % (W/V) SF solution, which was used to prepare 0.5 %, 1.0 % and 2 % (W/V) sulfadiazine sodium (SD) solution. Five layers of SFF was prepared with salivation method, dried under 37 °C, and annealed with 90 % (V/V) methanol. The structure information was analyzed by FT-IR and SEM, SD release in PBS (0.2 mol/L, pH 7.4) and PBS containing 2 U/ml trypsin at 37 °C was measured. The FT-IR spectra showed that more β-sheet was formed after annealed by methanol; a lot of pores were in the SFF and SD was embedded in SFF through analyzing the image of SEM. The release speed from SFF made by 5 % SF solution was faster than that from SFF made by 8 % SF solution. As for SFF containing different concentration of SD, the release rate improved with the increase of concentration of SD, however, the time of reaching the maximum were approximate. In PBS with trypsin, the time of reaching the maximum accumulative release was one hour earlier compared with in the PBS. Therefore, we draw a conclusion that the SFF incorporating SD has good properties and it has the feasibility to be used as artificial skin for burned patients.

The effect of microstructure on transport properties of nano-polycrystalline La0.7Sr0.3MnO3-δ films, which were prepared by DC magnetron sputtering at various working pressures and followed by air annealing at 973K for 1h, has been investigated. The result indicates that the change of working pressure can change the microstructure, metal-insulator transition temperature (TIM) and peak resistance but does not change the transport mechanism for the films. The vacancy defects have an important effect on the transport properties of the films. Higher working pressure tends to decrease the density of vacancy defects. Low vacancy defects account for the high TIM and low resistance of the films. In the region of T > TIM, the charge carriers are moving in variable range hopping mode. The behavior of resistance decreasing with the increasing of temperature at low temperature (T

Polycrystal samples of La1-xSrxMnO3 (x=0.2, 0.3) have been synthesized using a sol-gel method. The effect of sintering process on the sample microstructure and Sr doping on the magnetoresistance for La1-xSrxMnO3 have been investigated. The results show that the increase of sintering temperature and time can promote the crystallization of samples and reduce the content of impurity. The additive of Sr makes Mn ion in materials relatively compact, and this causes the distorted deformation of the materials structure. The magnetoresistance (MR) changes with the Sr doping. When x=0.2, the maximum MR% of sample is about 43% and keep about 40% between 10~150K. At room temperature, the MR% will decrease to about 6.5%. When x=0.3, the order magnetoresistance (OMR) effect occures above the room temperature.

The temporal dispersion effect and compensation approach of femtosecond laser scanning by an acousto-optical deflector (AOD) was studied. The group delay dispersion (GDD) of a single AOD at 800nm wavelength is about 9300fs2. Based on the principle of angular dispersion of AOD and the prism, an approach that uses single prism pre-compensating an AOD for the temporal dispersion was designed and demonstrated by experiments. At center frequency (70MHz) of the AOD, a 398fs pulse is compressed to 122fs, the range of pulse width on the entire bandwidth (50MHz—90MHz) is 120fs—180fs. This approach is demonstrated to be effective on compensation of temporal dispersion for AOD scanning femtosecond laser.