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Co-gasification of biomass after hydrothermal treatment (HTT) and coal blends had great potential to realize the clean and efficient co-conversion of biomass and coal. In this study, co-gasification reactivity and synergy of Shenfu bituminous coal and rice straw (RS) hydrochar (prepared at HTT temperatures of 200, 220, and 240 °C) blends (denoted as SF-RS200, SF-RS220, and SF-RS240) were investigated using a nonisothermal thermogravimetric analysis, and gasification kinetic analysis was conducted based on the Coats−Redfern method. The results show that different blends showed little difference in the initial temperature for weight loss, the final temperature for weight loss, and the temperature corresponding to the maximum weight loss rate during both co-pyrolysis (stage 1) and blended char co-gasification (stage 2), and only the maximum weight loss rate of different blends showed a relatively large difference. Reactivity of blends at both stage 1 and stage 2 decreased at a higher HTT temperature. There was no synergy behavior at stage 1. However, the synergistic effect at stage 2 was observed and was more significant for SF-RS200 and SF-RS220 compared with SF-RS240, which was mainly attributed to the potassium concentration difference among RS hydrochar samples led to various catalytic effects on coal char gasification at stage 2. Kinetics analysis demonstrates that both volumetric reaction model (O1) and shrinking core model (R2, R3) all showed high correlation coefficients (>0.95) for different samples and reaction stages. There were obvious kinetic compensation effects in the gasification process, and activation energy (E) and pre-exponential factor (A) of different samples followed a positive correlation relationship as ln A = 0.2340 × E − 4.3186 for stage 1 and ln A = 0.1217 × E − 6.2181 for stage 2.

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Ash fusion temperatures (AFTs) are important parameters influencing the stable operation of industrial entrained-flow gasifier. It is well known that the separate addition of CaO and MgO can ameliorate the ash fusibility. However, the synergistic effect of CaO and MgO on the ash melting characteristics is still unclear. For this sake, the ash fusion temperature analyzer (AFTA), X-ray diffraction (XRD), Raman spectrum, and FactSage thermodynamics software were applied to investigate the ash fusion behavior with various CaO/MgO mass ratios in this work. It showed that as the CaO/MgO mass ratio increased, the AFTs decreased first and then increased slightly with reaching the minimum at the CaO/MgO mass ratio of 8:2. When the CaO/MgO mass ratio was low, the formation of spinel with stable lattice was the main reason for the high AFTs. As the CaO/MgO mass ratio increased, the formation of low-melting-point feldspar minerals such as anorthite and melilite resulted in the AFT reduction. As well, when the mass ratio of CaO/MgO reached 8:2, the relatively high amorphous content led to the lowest AFTs. Additionally, the variation of the liquid slag content with the increase in temperature was analyzed, and the melting process was divided into the primary fusion stage and the free-liquid stage.

The tilt and decentration of intraocular lens (IOL) result in defocussing, astigmatism, and wavefront aberration after operation. The objective is to give a method to estimate the tilt and decentration of IOL more accurately. Based on AS-OCT images of twelve eyes from eight cases with subluxation lens after operation, we fitted spherical equation to the data obtained from the images of the anterior and posterior surfaces of the IOL. By the established relationship between IOL tilt (decentration) and the scanned angle, at which a piece of AS-OCT image was taken by the instrument, the IOL tilt and decentration were calculated. IOL tilt angle and decentration of each subject were given. Moreover, the horizontal and vertical tilt was also obtained. Accordingly, the possible errors of IOL tilt and decentration existed in the method employed by AS-OCT instrument. Based on 6–12 pieces of AS-OCT images at different directions, the tilt angle and decentration values were shown, respectively. The method of the surface fitting to the IOL surface can accurately analyze the IOL's location, and six pieces of AS-OCT images at three pairs symmetrical directions are enough to get tilt angle and decentration value of IOL more precisely.