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A total of 46 samples from nine types of commercially available foods for special dietary uses were collected for osmolality measurement by a freezing point and a dew point osmometer, and the differences between the two methods were analysed. The results showed that the detection range of the freezing point osmometer was 195–763 mOsmol/kg with relative standard deviation (RSD) of 0.20%–4.08%, and the detection range of the dew point osmometer was 197–649 mmol/kg with RSD of 0.00%–3.66%. It was found that different reconstitution methods had a significant effect on the determination results, and the temperature of the solution also affected the parallelism of the determination results. Statistical analysis using t-test showed that there were significant differences between the results of the two methods for each of 31 samples. It was inferred from the experiments that whether the sample solution reached an ideal dilute solution state was the major factor affecting the significant difference between both methods. This study provides a theoretical basis for further research on the detection of osmolality in foods for special dietary uses, and highlights some key issues that need urgent attention in the design and production of foods for special dietary uses.

To improve the effectiveness of urban planning, the effect of rail-transit construction on the value of residential projects along rail-transit lines should be assessed. In studies to date, the focus has been on the effects of various urban development elements on housing prices in rail transit station areas; however, there are few studies of the premium effects and value-capture mechanisms in rail transit station areas. In this study, the average price of a residence in existing residential neighborhoods in Hefei, using data published on the Anjuke website in December 2018, was used in an assessment of the value added of the Hefei Metro Line 1. The data included the name of the community, average price per unit area, location, housing age, floor area ratio, and greenery rate. Baidu POI data from December 2018 were used to determine bus routes and various public service facilities in the district. First, we constructed a housing price fitting model in the station area and analyzed the spatial value-added pattern of housing and the premium effectiveness of each fitting index. From this analysis we extracted the premium characteristics of housing projects in the station area and then determined the value capture mechanism and proposed optimization strategies. The results indicate the following: (1) The impact of Hefei Metro Line 1 on housing prices along the line is significant and decays with increasing distance from the rail transit station. (2) Different index elements have different effects on station-area residential premiums. The location and transportation level indicators contribute the most to the premium, followed by the neighborhood and environment level indicators. In contrast, the building form level indicators contribute the least to housing prices in this model. Specifically, the distance between the residential community and the rail station, as well as the distance between the residential community and the CBD, produce a significant negative price premium that decays with distance. Other indicators―housing age and presence of amenities such as hospitals, shopping malls, and museums―also have significant negative linear premium effect. The number of bus lines, as well as the greenery rate and presence of parks had significant positive linear premium effects. (3) Based on the model score results, quadratic groups were constructed to evaluate the station area, and the premium rule and geographical effect of the station area was established. The systematic connection between the premium effect and the value capture of the rail transit station area can be identified, the distribution characteristics of the housing price of the station area can be accurately identified, and the current differences in the degree of residential premium in the station area can be indicated. Furthermore, based on the case of the Hefei metro area, the interaction between rail transit financing and value capture was analyzed for its applicability to China's public ownership land system. Accordingly, a land use strategy with institutional feasibility is proposed, and different models and implementation mechanisms of premium allocation are suggested, which are of great importance in terms of promoting the return of rail transit premiums to the public, the sharing of land benefits among urban residents, and, ultimately, sustainable social and economic development.

针对当前通用型称重料仓工艺烦琐和设备复杂的问题，以大豆为例，运用模块化集成设计理念，采用理论分析与仿真模拟相结合的方法，设计开发了一套集卸料器与料仓于一体的气固分离称重料仓。采用Solidworks三维建模软件将设备各部分构件建模，运用计算流体力学及离散项模型对气固分离称重料仓的关键结构进行分析。结果表明，设计的气固分离称重料仓在完成称重卸料的同时可分离轻杂，简化了称重卸料过程，新增的蝶阀模块可根据料仓内的物料量动态调整进出仓过程。综上，设计的气固分离称重料仓可用于气力输送大豆的称重卸料。 Aiming at the problems of the cumbersome process and complicated equipment of the current general-purpose weighing silo, taking soybean as an example, using the modular integrated design concept and the method of combining theoretical analysis and simulation, a set of gas-solid separation equipment for weighing silo integrating unloader and silo was designed and developed. The Solidworks 3D modeling software was used to model each part of the equipment. The key structure of the gas-solid separation equipment for weighing silo was analyzed by computational fluid dynamics and discrete phase model. The results showed that the designed gas-solid separation equipment for weighing silo could realize the separation of light impurities while completing weighing and discharge, and simplified weighing and discharge process. The newly added butterfly valve could dynamically adjust the process of inlet and outlet according to the amount of material in the silo. In conclusion, the designed gas-solid separation equipment for weighing silo can be used for weighing and unloading of pneumatically conveyed soybeans.

The rotary excitation valve is one of the key components for the high-frequency and high-pressure electro-hydraulic excitation system, and its dynamic characteristics directly affect the performance of the entire excitation system.In order to study the dynamic characteristics of the rotary excitation valve under the coupling effect of Fluid-Thermal-Solid multi-field. First, the flow field of the rotary excitation valve was dynamically simulated by the sliding grid method through Fluent simulation, and the simulation results were verified by the measured flow rate of the rotary excitation valve. Then, the Fluid-Thermal-Solid multi-field coupling simulation of the rotary excitation valve was performed by using ANSYS. The thermal characteristics and thermal deformation laws of the rotary excitation valve was studied when the pressure difference between inlet and outlet ΔP are 5 MPa, 10 MPa, 15 MPa and the oil temperature are 20℃, 40℃, 60℃ respectively. The research results show that the internal flow field and temperature field of the rotary vibration valve are not uniformly distributed. The temperature of fluid near the valve core and the wall of valve body is higher, and the center temperature is lower.Due to the impact of the fluid at the outlet of rotary excitation valve, a local high temperature will be generated, resulting in thermal deformation of the valve core groove and the valve body outlet port.When the pressure difference between inlet and outlet at 15 MPa, the thermal deformation is 3.789 4 μm, and the oil inlet temperature at 60℃, the thermal deformation is 7.701 7 μm. Therefore, choosing the pressure difference between inlet and outlet and oil temperature is beneficial to the operational characteristics for rotary excitation valve. The theoretical data for the structural design and optimization of the rotary excitation valve are provided.