Applied Mechanics and Materials Vols. 303-306

Abstract: A series of chiral [6]helicenes have been designed using the molecular engineering of organic nonlinear optical materials. The geometries of [6]helicenes 1, 2, 3, 4,5 are optimized using density functional theory (DFT-B3LYP) method at the 6-31g (d, p) basis set level. Based on the obtained stable molecular configuration, we adopt the TDHT/PM3 method and time-dependent density-functional theory (TD-DFT) to calculate the nonlinear optical (NLO) properties and electronic spectra of these molecules. Results show that the static hyperpolarizability βµ alternates between positive value and negative value, whereas it remains positive for the molecues 2 and 3 which have medium magnitudes βµ, 3.4×10-30esu and 9.6×10-30esu respectively. In molecule 5, there exists two competitive charge transfers that reduce the hyperpolarizability β.

Abstract: Although the bag-type dust collector is dust capture equipment which is low cost and high efficiency, it has less filter efficiency to ultra fine particles for its of thicker fiber. So ultrafine fiber were used by bicomponent fiber with splitting craft to improve the filtration efficiency of ultra fine particles greatly. A piece of polyester/nylon sea-island superfine fiber needled nonwovens were splitted processing for nine times by the orthogonal design. And fibre microscopic photographs, weight loss rate and strength were analyzed. The best choice of splitting craft as followed: lye concentration is 16%, splitting time 15 min and splitting temperature is 95 °C.

Abstract: This paper, a comprehensive analysis of selective flocculation am fine hematite selected based on the combination of soluble starch and the characteristics of acrylamide was prepared soluble starch - grafting of acrylamide polymer flocculant. Conditions of single-factor experiment studied the conditions on the starch - the impact of acrylamide polymerization and to the level of starch graft ratio to measure the various conditions on the polymerization to determine the optimal conditions of each are as follows: initiator using cerium nitrate Ammonium; initiator concentration 0.001moL / L; AM / soluble starch mass ratio of 2:1; reaction time of 2h; the reaction temperature is 60 °C. In terms of single-factor test, designed a four factors and three levels of the orthogonal test, the optimum conditions are: starch and monomer mass ratio of 1:2; initiator concentration of 0.001 mol / L; the reaction temperature is 65 °C; reaction time was 1.5h. Under these conditions, starch and the grafting rate of 153.24. By scanning electron microscopy and infrared spectrum we can see, the namely, the resulting polymer soluble starch and acrylamide graft copolymer. By hematite flocculation test we can see, with flocculants prepared by flocculation, its ability to better than selective flocculation.

Abstract: The dynamic characteristic parameter of conveying property of pulverized coal is described with the conveying mass of pulverized coal in unit time. The conveying process of pulverized coal is studied by means of the pulverized coal’s conveying property testing equipment developed by ourselves. Results show that the conveying property of bituminous coal is better than anthracitic coal. If the improvement of conveying property of pulverized coal is considered purely, the size of pulverized coal can properly be reduced and the proportion of anthracitic coal can properly be decreased. The water content of pulverized coal can be controlled from 1% to 2%.

Abstract: In order to use resonably fuel resources and reduce cost of manufacture, the effects of coke and coal powder on chemical coposition and metallurgical properties of sinter were studied with the iron ore blender as the iron-contained materials. Results shown that the reducibility at 900°C was slightly improved and the low temperature reduction degradation index was worsened with the coke powder as the solid fuel relative to coal powder under the equal calorific value condition. However, with the increasing of solid fuel ratio, the mechanical strength and low temperature reduction degradation index was improved.

Abstract: Sheet metal parts are widely used in auto body and airplane body. As the method of influence coefficient cannot accurately analyze the relationship between part deviations and assembly variations, this paper proposes a new variation analysis model based on a method of power balance for sheet metal parts. The simple metal planes are loaded to fixtures according to the principle of “4-2-1”; and then variety of part deviations is analyzed during assembly process. The analysis shows that the welding guns do same work during welding process. Based on the above, this work establishes sensitive coefficient matrices between part deviations and assembly variations. Finally, two Z-shape sheet metal parts illustrate the assembling variation analysis process and the results indicate the accuracy of the method of power balance.

Abstract: Stone Matrix Asphalt (SMA) is regularly and successfully used for surface courses in many countries. In this study SMA was designed using two different local aggregates blending ratios. The aggregate blends were tested for density, abrasion, crushing, water absorption and polishing before used in SMA design. Laboratory testing of the SMA surface mixtures was performed to determine volumetric and mixture specific characteristics. The results and analysis determined that SMA is a good surface meeting the design demands. All mixtures were tested for textural depth and skid resistance performance. It was concluded from this study that different aggregate blending can significantly alter the SMA mixture properties. The limestone and basalt blends can be successfully used to design an anti-slide SMA surface course.

Abstract: Although the ozonation chemiluminescence can be used to determine organic matter fractions (lipids, acid soluble fractions, acid insoluble fractions), the process is not clear, e.g., what is produced after the organic matter is oxidized by ozone (O3), how much product and reactant are in the ozonation, how to define the complete oxidation Aimed at resolving these questions, we designed an experiment. On the special equipment developed for the ozonation chemiluminescence studies, two instruments of determining O3 concentrations and two flowmeters were installed to measure the input and output amount of O3 and the amount of O3 consumed can be calculated. Results showed that 1) acid insoluble fractions are oxidized to lipids and acid insoluble fractions; 2) the amount of the product is determined by the amount of reactant and consumed O3 ( ); 3) when the reactant is as result 2), the oxidation is complete, or when the organic matter fractions are stable after ozonation, the oxidation is complete. Further study should test the process at the molecular level.

Abstract: Twenty-two endophytic fungi in the Huperzia serrata were separated to test their fermentation broth. Research found that seven of them could produce alkaloid. Of these, the fermentation products from the T4 bacterial strain produced the most, with 2.027 mg/g. Ellman colorimetry has determined that the fermentation broth in four fungi had inhibition activity against AchE. It also showed that the total alkaloid of the T17 bacterial strain had a half-inhibitory concentration (IC50) of 98.494 μg•mL-1 on the mouse’s brain against AchE. This yielded the conclusion that the total alkaloid in the T17 fermentation broth restrains AchE effectively, and that it further contributes to the separation of its active ingredient.

Abstract: Stimuli-responsive hydrogels are extensively investigated to implement new biomedical and pharmaceutical approaches. In this work, novel pH-sensitive hydrogel, with potassium persulfate as the initiator, acrylic acid and butyl methacrylate as graft monomer, were synthesized by microwave irradiation. FT-IR measurements testified the hydrogels formed structure. The SEM micrographs revealed that the porous structures of hydrogels changed with the increasing AA content. The experimental results demonstrated that the gels do not swell greatly at low pH media whereas they swelled sufficiently at high pH media, exhibiting smart pH sensitivity.