Advanced Materials Research Vols. 236-238

Abstract: A heat transfer model of PEMFC is developed that captures dynamic behavior for control purposes in this paper. According to the law of conservation of energy, by analyzing in detail the heat source, considering the heat of electrochemistry, activation polarization heat and the heat loss of air forced convection etc., the dynamic heat model of PEMFC is established. Among all influential factors of fuel cell temperature, current density is one of the most important influence factors. Finally, by comparing the response results temperature with the current density changes between simulation and experiments, the results s are consistent. The model in this article has an important guiding significance for the design of fuel cell. For example, the working temperature of fuel cell can keep up stability by controlling cooling medium flow rate etc.

Abstract: Current logistics status of a company’s flywheel workshop has been analyzed, according to such main principles of enterprise logistics optimization as avoid roundabout and backflow of materials, minimum distance, manpower saving, using gravity, systematization and so on, it optimizes logistics of the workshop. Comparing the data of optimization before and after, it is obvious that the process routes have been improved, logistics is smooth, transportation distance has been reduced, production cycle is shorter, production efficiency of the workshop has been greatly improved and it achieved distinct improvement.

Abstract: In this paper, using the discrete element method (PFC^2D)particle flow procedure to establish a model of cylindrical silo, in the warehouse filled with particles within the reach of static equilibrium state, then the record of its wall static lateral pressure measurement value, while monitoring the measured dynamic wall pressure during the silo discharging. It was shown that the static pressure as well as the dynamic pressure simulated with the numerical model is in good agreement with the experimental results. So the discrete element method can give a new way to study dynamic question of silos.

Abstract: A method for the simultaneous separation and determination of vanillin and o-vanillin by capillary electrophoresis (CE) was developed. The influence of type, concentration and pH of running buffer, and applied voltage on separation was investigated. Under the condition of 50 mmol/L borax-150 mmol/L disodium hydrogen phosphate (pH 7.5) and applied voltage of 15 kV, the vanillin and o-vanillin were separated in less than 6 min. The method was validated in terms of accuracy, precision and linearity and proved to be robust. This CE method is comparable with high performance liquid chromatography (HPLC). This CE method is applicable to the quantitative analysis of Vanillin and o-vanillin in real samples, and the assay results were satisfactory

Abstract: A simple, sensitive and rapid method for flow injection with chemiluminescence analysis has been developed for the determination of prednisone acetate at trace level. This method is based on the luminescent properties of the tris(1,10-phenanthroline) ruthenium(II)-potassium permanganate -prednisone acetate in acidic medium sensitized by Na₂SO₃. The optimized experimental conditions are evaluated. Under the optimum experimental conditions, the linear ranges of prednisone acetate are: 4.0×10^-10~4.0×10^-8 g·mL^-1 and 4.0×10^-8~2.0×10^-7 g·mL^-1 with a low detection limit is 4.5×10^-11 g·mL^-1 and the relative standard deviation for 1.0×10^-8 g·mL^-1 sample is 1.04% (n=11). The proposed method has been successfully applied to the determination of prednisone acetate in tablets.

Abstract: In this paper, Provolone Cheeses were radialized by 60Co-γ of different doses, and they were stored. The impact of texture in the cheese after radialization was studied, the peculiar smell resulted from radialization were analyzed, the mechanisms and preventing methods were discussed. Main conclusions are as follows: Volatile flavors of Provolone cheeses of different radialization doses were detected by HS-SPME-GC-MS. The result showed that the variety and quantity of volatile flavors were changed obviously after radicalization: esters and phenols were reduced numerously; while aldehydes, ketones, aromatic hydrocarbons and alkyl olefin had increased significantly; Irradiation cause sulfur compounds such as sulfur alcohols and sulfur ketone.

Abstract: In this paper, the volatile compounds of the dorsal meat of cultured grass carp in different seasons were identified by SPME(solid phase micro-extraction)-GC (gas chromatography)-MS (mass spectrometry). The results showed that SPME was effective to analysis of the volatiles in grass carp. According to GC-MS, 21, 43, 42 and 42 volatile compounds were detected in dorsal meat of grass carp in spring, summer, autumn and winter respectively. The volatile components are mostly carbonyl compounds and alcohols, the respective relative contents are above 90%. The relative content of the volatile compounds of cultured grass carp in different seasons has the significance difference by ANOVA. Seasons have greater effect on the volatile compounds of dorsal meat of grass carp. The study will enrich the theoretical knowledge of flavor chemistry and provide an effective solution to the current situation of low proportion of fish processing.

Abstract: To elucidate the effects of implants fabricated by three-dimensional printing (3DP) technologies, a novel technique enables the complex implant release profiles, precise dosage control and rapid formulation in a single form. In this study, a unique implant with polylactic acid-based polymer powders was developed by the process. Test of the morphology and the releasing experiments in vitro of the implants were done to evaluate the implant devices. At about 100-day release of the implants in vitro, the drug concentration was measured and the profiles were made. The morphology of the implants of both technologies was characterized by three dimensional stereoscopy and environmental scanning electron microscope. The release behaviour and the microstructure were detected to compare the effects. 3DP technology allows the design and fabrication of implants with a novel micro- and macro-architecture which cannot be fabricated or may be fabricated with many difficulties in conventional technology.

Abstract: In order to improve the quality of the black-skin-red-kojo, the Chinese rice wine yeast was introduced in the koji-making process，and adjusted the proportion of Monascus and Aspergillus niger and optimized the water content．Effects of different factors on the quality of the koji were investigated and the optimal process conditions were obtained through the orthogonal tests.

Abstract: In order to decrease the residue content of sulfite of apple slices, the desulfurization by water, alkali solution and ultrasonic were studied. Results showed that the optimal parameters of the orthogonal design for eliminating the sulfur by water were: 60°C of temperature, 1:6 of solid-liquid ratio, 45 min/time of water refresh cycle, 3h of time. In this optimal condition, the desulfurization was 96.054%, and the residue content of sulfite was 0.090 g/kg. While the optimum conditions of alkali method were: using 0.06% Ca (OH) ₂ with the solid-liquid ratio 1:5.4 at 54°C. In this optimal condition, the desulfurization rate was 96.673%, and the residue content was down to 0.076g/kg.The optimal parameters for eliminating the sulfur by ultrasonic were: solid-liquid ratio1:6, treatment time 25 min, ultrasonic power 120w, temperature 35°C. In this optimal condition, the desulfurization rate was 97.418%, and the residue content of sulfite was only 0.059g/kg.