Advanced Materials Research Vols. 798-799

Abstract: The concentration of urea generated by Huangjiu yeast at the different conditions was measured with diacetyl oxime colorimetric method. The results show that the production of urea generated by yeast in fermentation process is different from culture conditions. The level of urea of control group is higher than the levels in other conditions. The urea concentration in culture medium presents increasing in the early growth stage and then decreasing in the later growth stage.

Abstract: To obtain the better formula of the biomaterials lyoprotectant for composite starter of Paocai, five lyoprotectants were studied with math method those are orthogonal design, Quadratic polynomial stepwise regression and etc. The results showed, 14.7% of hydrolyzate of skim milk, 1.1% of amount of glucose, 3.4% of amount of glycerol, 5.0% of amount of sodium glutamate, 1.2% of amount of Vc were added to the culture of Lactobacillus. After lyophilized, colonies of freeze-dried starters can reach 3.25×10¹⁰ cfu/mL. Response surfaces are drawn according to the mathematical model among factors, and it was discussed the impact of lyoprotectants.

Abstract: The coffee flavor compounds acquire a significant place in the improving the flavor of cigarette. In the present paper, the heuristic method is used to develop quantitative relationships between the retention time (TR) and four molecular descriptors of 52 compounds. The model of heuristic method gives good statistical result. The contribution of each descriptor to structure-retention time relationships was evaluated. It indicates the importance of the atoms number and type of parameter. The proposed method can be successfully used to predict the retention time with only four molecular descriptors which can be calculated directly from molecular structure alone.

Abstract: Activated toxins interact with α-amylase receptor on the brush border membrane vesicle (BBMV) of the midgut epithelium, which activates intracellular oncotic pathways and leads to cell death. In order to decipher the mechanism of process how toxins interact with their receptors, it is essential to investigate their three-dimensional structure. The three-dimensional structure of α-amylase was constructed by homology modeling, based on crystal structure of Bacillus cereus oligo-1,6-glucosidase and the model was further evaluated using PROSA energy and ERRAT. The substrate binding pocket responsible for the interactions with toxins was predicted and analyzed, and the important role of binding of toxin to binding pocket on α-amylase was discussed in the aspect of Cry4Ba and Cry11Aa toxicity.

Abstract: Effects of inoculation quantity, culture temperature and time on glucoamylase activity and the optimum conditions of koji-making of Aspergillus oryzae was studied by using single factor and response surface experiment. The results show that 3 factors can significantly impact on glucoamylase activity of koji. The best process condition of koji-making obtained by using the "Design-Expert" software is: culture temperature 38.70 °C, inoculation quantity 0.85 , and culture time 50.47 h.

Abstract: According to the definition, objectives, and functions of the health care system, the paper assesses the performance of this system, describes several metrics which can evaluate the effectiveness of a countrys health care system, and constructs synthetic model by synthesized osculating value method and fuzzy comprehensive evaluation method to evaluate the effectiveness of a countrys health care system. Firstly, the paper evaluates degrees of these metrics, and gets the result that infant mortality per 1000 births is the most important metric while obesity rate is the least important one. Secondly, it compares the health care system of United States with other countries which have different levels, and the results coincide with the reality. Finally, the paper provides 5 pieces of advice for improving the overall quality of the system.

Abstract: New series of 4-methyl and 3,4-dimethyl-7-oxycoumarin derivatives showed in vitro high anity and selectivity toward MAO-A isoenzyme. To build the quantitative structure-activity relationships (QSAR) between the molecular structures and the inhibitory of 32 compounds, and to further discuss the structural factors that influenced the selectivity of compounds. The topological, constitutional, geometrical, electrostatic and quantum-chemical descriptors of 32 compounds were calculated by CODESSA, and these descriptors were preselected with the heuristic method (HM). As a result, the four descriptor linear model was developed to describe the relationship between the molecular structures and the selectivity of MAO-A inhibitors. Based on the model, we can also designed new compounds with higher activities finally.

Abstract: Urban transportation is the main way of carbon emission, development of low-carbon transportation has become the focus of attention of the countries all over the world. This paper analyses the influencing factors of carbon emission of Tianjin transportation based on grey correlation method, putting forward that the cost of urban resident transportation, traffic volume of urban passenger, number of private car and energy consumption of urban transportation are the most important key factors. Therefore, in order to construct low-carbon transportation system, Tianjin should design the layoff of urban space reasonably to control the demand of transportation effectively to reduce the urban transportation cost first, develop urban public transportation to optimize the urban traffic structure in response to the growing urban traffic volume of passenger second , establish a series of laws and regulations to improve the urban traffic management level to strengthen the supervision of private cars third, develop and apply new technology and new energy to adjust the energy structure of urban transportation to reduce urban transportation energy consumption at last.

Abstract: Recently, there were many accident of small dam break of reservoir in China, which reflects a problem in construction and management of small reservoir. By studying over 306 reservoirs which have been reinforced, the main problems to the safety operation of reservoir were concluded. The main 17 problems and 10 questions were discussed in this paper and the answers and suggestions are also made.

Abstract: The activated carbon with high surface area was prepared by KOH activation from anthracite and used as adsorbent for removal of Cr (VI) from aqueous solution. The pore structure and surface properties were characterized by N₂ adsorption at 77K, transmission electron microscope (TEM) and Fourier transform infrared spectroscopy ( FTIR). Effect of pH and isotherms at different temperature were investigated. Results show that the prepared carbon is a microporous-and mesoporous-adsorbent with developed pore structure and abundant surface oxygen-containing groups. PH value of the solution plays key function on the adsorption. The chemical adsorption dominates the adsorption process. The activated carbon exhibits much higher Cr adsorption capacity than the commercial activated carbon at initial pH of ~3. The equilibrium adsorption data are fitted by both Freundlich model and Langmuir model well.