As the casting film is very thin (micron scale), if the 1∶1 geometric model is used to simulate the heat transfer of thin film, the number of grids will reach 10 billion level, and the simulation calculation will become very difficult. Therefore, this paper proposed a heat transfer simulation model of thin film thickening. In other words, the geometric model of film is enlarged, while the geometric model of roller and cooling water pipe remains unchanged, which can successfully realize the heat transfer simulation of the film cooling process. The study show that the temperature field on the surface of the film and the roller presents a spiral distribution, namely,“channel trace”, which is consistent with the thermal imaging test results. At the position with spiral guide vane, the surface temperature of the film and roller is high, the temperature of the corresponding position of the cooling water channel is low, and the film temperature fluctuates up and down in the axial direction of the film, with an amplitude of less than±1℃. The cooling process of casting film on the tape casting roller can be divided into two stages:temperature quenching stage and temperature stable stage. The cooling of the film mainly occurs in the quenching stage, and the quenching time is 0.03s, during which the film temperature can rapidly dropped to less than 40℃ from 220℃. The increase of the cooling water velocity in the spiral channel has little influence on the temperature change of the film in the circumferential direction, but has great influence on the average temperature rise slope of the film in the axial direction. The relationship between the flow velocity of cooling water in the spiral channel of tape casting roller and the slope of film axial temperature rise given at the end of this paper can provide technical reference for the design of flow rate of casting roller.

The cardo-type polyimides containing hydroxyl groups (PI-OH) were synthesized with one-step chemical imidzation method by taking hydroxyl-containing fluorene diamine and 44′-(44′-Isopropylidenediphenoxy) diphthalic anhydride as substrates. Then, cardo-type polyimides with low polarity and bulky size propionyloxy side groups (PI-OA)/tert-butyldimethylsiloxy side groups (PI-OSi) were prepared by acyl oxidation or silyl ether reaction of side hydroxyl groups. The effects of side group substitution on the solubility, optical and dielectric properties, etc. of PI-OH were systematically investigated. The results show  that the polarity and size of side groups greatly impacts the performances of PI films. Compared with PI-OH, PI-OA and PI-OSi show better solubility, higher transmittances and lower dielectric constants. Both can dissolve in low polar solvents such as dichloromethane or acetone. Their transmittances at 450nm can reach 86.7% and 85.2%, their dielectric constants are as low as 2.75 and 2.63 (1MHz). PI-OA and PI-OSi exhibit lower glass transition temperature and higher thermal expansion coefficients due to the introduction of low polarity and bulky size substituent groups.

Glucose and octenylsuccinate anhydride (OSA) were modified by esterification. The synthetic octenylsuccinate glucose ester (OSGE) was separated and purified to prepare OSGE with a sugar ester content of about 50%. Its irritation or interfacial properties were studied by taking linear sodium dodecylbenzene sulfonate (LAS), alkyl polyglucoside (APG) and cocamidopropyl betaine (CAB) as control group. Results show that the surface tension of OSGE and LAS is about 28mN/m; the critical micelle concentration (CMC) of surfactant follows the order: OSGE < LAS < APG < CAB; the hydrophile-lipophile balance (HLB) of OSGE is 16.90, indicating its highest hydrophilic property. No significant difference was found among OSGE, LAS and APG in emulsification ability, while irritation of OSGE is much lower than that of other three surfactants. 

Based on the surface sizing process in the papermaking field and simple inkjet printing technology, a hydrophilic microfluidic channel was constructed on the surface of the paper. Taking the wettability of the paper surface and the diffusion property of the liquid in the channel as the evaluation criteria, the paper studied the effect of surface sizing agent ratio and calendering treatment on the diffusion behavior of fluid in the microfluidic channel. First, the cellulose paper was hydrophobically modified by using a surface sizing agent with a ratio of 7∶3 (msurface sizing starch/mAKD), and then the modified paper was calendered at the pressure of 2MPa with a speed of 3.5m/min. The results demonstrated that constructed microfluidic channel exhibited an excellent liquid limiting performance. In these hydrophilic channels, the liquid can achieve a complete directional diffusion, and the z-direction liquid diffusion problem was also solved. Finally, the paper-based chip was further applied for the quantitative detection of nitrite, which shows that there is a good correlation between the solution mass concentration and the color difference value of the chip surface. The corresponding curve fitting equation is y=1.799＋8.745x0.453  and the correlation coefficient is 0.9935.

CuO-Bi2O3/H-β catalyst with high dispersion was prepared by taking H-β molecular sieve as the carrier，and butanone （MEK） and acetone （Ace） were prepared via the decarboxylation of levulinic acid （LA）.Then，the parameters affecting the decarboxylation performance of LA were investigated and the catalysts were characterized．Under the condition of 290℃，initial pH 5~6 and decarboxylation reaction for 3h，the conversion rate of LA can reach 88.06%，the yield of MEK can reach 40.75%，and the total yield of MEK and Ace can reach 61.05%.The research results show that the catalyst has high decarboxylation activity and excellent recycling performance.Moreover，the characterization results show that CuO-Bi2O3/H-β possesses both weak acid-base sites and medium-strong acid-base sites，and the introduction of Bi element promotes the dispersion of CuO in the carrier，and that the Cu/Bi component plays a synergistic catalytic decarboxylation role.

Dangerous chemicals leakage and diffusion accidents occur occasionally in the chemical plant.The key to dealing with such accidents is to confirm the location and rate of leakage sources quickly and accurately.Aiming at the defects of traditional leakage source inversion method，which is time-consuming and low accuracy，this paper proposes a leakage diffusion accident inversion method based on chicken swarm optimization （CSO） algorithm.This method takes the error between the gas concentration data monitored by the gas sensor and the calculated value of the model as the optimization objective.It transforms the inversion problem of hazardous chemical leakage and diffusion accident into an optimization objective minimization problem，and solves this problem with the chicken swarm optimization algorithm.In order to improve the accuracy of the algorithm，a weighted centroid method is used to construct a high quality initial solution set，which achieves an accuracy of 1m.The simulation results show that the chicken swarm optimization algorithm can accurately find the leakage source location in a short time，and its robustness can meet the actual demand; and that the method can realize the rapid and accurate positioning of hazardous chemical leakage sources in the chemical park and the accurate estimation of the strong leakage sources，thus providing timely and effective support for emergency decision-making.

Nanofluid composed of molten salt and nanoparticles are important materials for the effective power ge-neration and heat storage system of solar energy.It is of great significance to find out why nanoparticles are able to enhance the specific heat capacity of molten salt.In this paper，nanoparticles were added in molten salt at diffe-rent contents，and the specific heat capacity variation of complex fluids was measured by means of DSC.Then，the molecular dynamic simulation was adopted to explore the reason for the rise of specific heat capacity of complex fluids.In the simulation，the number of molten salt molecules is fixed and the content of nanoparticles is changeable，so as to analyze the effects of the content of nanoparticles on the specific heat capacity，structure and distribution of molten salt.It is indicated that，when the mass fraction of nanoparticles is 1.0%~1.5%，the increase of specific heat capacity is the largest.The additional interaction force produced by the high-density clustering of molten salt anions on the surface of nanoparticles or by the regular restricted distribution on the surface of nanoparticles with smaller particle size （about 1nm） is the main reason for the increase of the specific heat capacity of nano-fluids.In addition，calculation results confirm the positive correlation between the dispersity of the nanoparticles and the increase of specific heat capacity.The addition of nanoparticles can reduce the distance between anion and cation in molten salt to a certain extent，resulting in the change of Coulomb energy，which is another reason for the increase of specific heat capacity.

As a permanent implantable medical material and pharmaceutical formulation component，Polyvinyl alcohol （PVA） has a wide range of applications.In this work，water was used as the only medium to successfully prepare a composite fluorescent hydrogel of PVA，carboxymethyl cellulose （CMC） and carboxymethyl cellulose/rare earth complex （CMC/Eu，i.e.CE） by a freeze-thaw cycle method.The morphology and structure of the hydrogels were characterized by SEM and FT-IR.The results show that hydrogen bonding and other interactions occurred among CE，CMC and PVA to form multi-pore structure.DSC and XRD results show that the crystal structure of PVA is retained in the hydrogel after the addition of CMC，but the crystallinity decreases.The improvement of the mechanical properties of these hydrogels is due to the hydrogen bonding of the hydroxyl in CE，CMC and PVA molecules as well as other interactions between molecular chains，which improve the fusion between molecular chains and enhance the bonding strength among various components.Especially，when the mass ratio of CMC to PVA is 1：5，its tensile modulus of elasticity can reach 39.86kPa，and the compressive modulus of elasticity can reach to 273.31kPa.Photoluminescence （PL） results show that the PVA/CMC/CE hydrogel has the 5D0→7F2 characteristic emission peak of Eu3+ near 635nm when the excitation wavelength is 394nm.It displays red fluorescence under ultraviolet light，indicating that the hydrogel has a basis for potential applications in fluorescent probes，anti-counterfeiting and biomarkers.