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To provide reference for technical feasibility and process setting of physical cold disinfection of salad dressing, the commercial salad dressing was irradiated by electron beam at different doses of 0 kGy,1 kGy and 2 kGy. The disinfection effect of electron beam irradiation on salad dressing and the changes in terms of microorganism, color, texture, flavor, stability of irradiated salad dressing after storing for 40 days at room temperature were studied. The results showed that, electron beam irradiation had a good disinfection effect on Salmonella typhimurium, Escherichia coli, Staphylococcus aureus, the aerobic plate count, molds and yeasts of salad dressing. 1 kGy irradiation could reduce pathogenic bacteria by 3 log to 6 log, with no aerobic plate count, molds and yeasts found. After 40 days storage at room temperature, sensory evaluation showed that electron beam irradiation at 1 kGy had no significant effect on the color, texture, aroma and taste of salad dressing. There was no obvious difference in the results of electronic nose analysis, texture parameters and centrifugal resolution rate, but the taste score of 2 kGy irradiation was significantly lower than that of non-irradiation and 1 kGy irradiation. Significant difference of texture parameters was found between 2 kGy irradiation, non-irradiation, and 1 kGy irradiation. Therefore, we conclude electron beam irradiation can effectively control the pathogenic bacteria in salad dressing. The electron beam irradiation at doses of 1 kGy has no obvious undesirable effect on the color, texture, flavor, stability of the salad dressing, which could be used as a disinfection method for salad dressing.

Consolidation and permeability tests were conducted on soft clays with different liquid limit by GDS consolidation apparatus. Some fitting parameters were studied for 4 common nonlinear permeability models based on the test data. But different soil samples have different parameters for the same model. In order to find the universal law of permeability coefficient and compressibility with the soil property and void ratio, the void ratio was normalized by the liquid void ratio eL, and the relationship of e/eL with logkv and logp were established based on the test data. The Chapman-Richard curve fitting model was adopted to best fit the obtained time-compression data. The relationship between e/eL with logkv was further verified using 30 groups of test data of permeability collected from China and abroad. The relationship between e/eL with logp was also discussed in this paper, and the fitted curves and nonlinear equations was further simplified into two linear equations at the point of e/eL=0.9 so as to consistent with the well-known theory. The nonlinear equations can be used to calculate the permeability and compressibility according to the void ratio and liquid limit.

The synthesis conditions of the 11C-Raclopride with domestic PET-CM-3H-IT-I synthesis module and 11C-Triflate-CH-3I as methylation agent were studied, which included the alkali equivalent, solvents, temperature, the amount of precursor and elution conditions for the product. The optimum condition was 1.5-3.0 g/L of precursor in acetone (0.2 mL), alkali equivalent (0.30-1.25 eq) and at room temperature (25 ℃) for synthesis of 11C-Raclopride. It could be got with radiochemical yield of (64.82±4.74)% (n=46, EOB of 11C-Triflate-CH3). The radiochemical purity was over 97% and the specific activity was at (423.61±13.43) GBq/g. It took 23 minutes from 11C-CO2 to 11C-Raclopride, and the production radioactivity was (6.9±0.87) GBq (n=46). The synthetic process was reliable and reproducible, and the product synthesized by this process was suitable for clinical use.

Herein, we developed a metal‐free, photosensitized strategy for difunctionalization of olefin feedstocks to access β‐amino sulphone architectures, enabled by a tailor‐made, readily accessible sulfonylamide bifunctional reagent. This protocol could accommodate a wide range of alkenes and a variety of sulfonylamides, with high yields and excellent regioselectivity. Given remarkably mild reaction conditions, readily accessible starting materials, excellent functional group tolerance, and well‐defined regioselectivity, this approach would enable an efficient platform for the assembly of densely functionalized molecular scaffolds. [ABSTRACT FROM AUTHOR]