Advanced Materials Research Vols. 807-809

Abstract: This paper compared the differences of laccase modified APMP and unmodified controlled trails to characterize laccase’s impacts on the whiteness, physical properties and fiber morphology of APMP. From this paper, we can see that after laccase modified, the whiteness of the APMP significantly reduced; physical properties of the APMP were reduced after the first enhanced with increasing the amount of laccase. when the amount of laccase was 2u/g, the physical properties of the APMP were best, the same time after 2u/g laccase treatment ,the surfaces of the pulp fibers engendered the devillicate and peeling.

Abstract: In this paper the two-stage method of enzyme-mild acidic hydrolysis was adopted to isolate lignin from the APMP(Alkaline Peroxide Mechanical Pulp),then the isolated lignin was treated with a laccase-mediator system(LMS).The phosphor magnetic resonance spectrum (31P-NMR) measurements and Infrared spectral analysis technology were chosen to analyze the structural changes of LMS-treated APMP residual lignin.

Abstract: Mechanisms and defiberation point of pinus kesiya diethanolamine pulping were analyzed in this paper. The results show that the delignification of diethanolamine cooking is divided into three stages: the initial delignification stage, which is from the beginning of heating to 170°C, and its delignification rate is about 30%; the bulk delignification stage, which is from 170°C to 200°C for 60min with the total delignification rate about 90%; the supplementary delignification stage, which is from 200°C for 60min to the end of cooking, and its delignification rate is more than 97%. And the defiberation point is at 200°C for 30min nearby.

Abstract: Stalk concrete block was made of compressed wheat stalk brick and hollow concrete block. Experimental study on heat preservation performance of stalk concrete block and stalk concrete block was carried out. Average heat transfer coefficient of experimental wall made by hollow concrete block is 1.57 W/m².K and stalk concrete block is 1.08W/m².K. Performance of moisture transfer of compressed wheat stalk brick was acquired by using thermostatic and humidistat chamber. Profile of humidity absorption and release was also acquired. The maximum moisture content of compressed wheat stalk brick is 8.85 %. Relative humidity in certain space can be controlled within 50 % -65%.

Abstract: Graphite oxide was prepared by Hummers method and got graphene oxide by ultrasonic dispersion in water, and using a cheap and environment-friendly fructose as reductant, graphene oxide could be reduced into graphene under mild condition. Meanwhile, the structure and morphology of obtained product was characterized and analyzed by testing methods such as Fourier transform Infrared spectroscopy, X-ray diffraction, Laser Raman spectroscopy, Transmission electron microscope and so on. In addition, the electrical conductivity of obtained graphene was determinated.The experimental results show that graphite oxide can be reduced by fructose under mild conditions and can get graphene with good structure and dispersibility. And the electrical conductivity of graphene prepared by the reduction of graphite oxide with fructose is 35.7 Scm^-1, which has great improvement on conducting performance compared with graphite oxide. Moreover, It is non-toxic, non-polluting and friendly to the environment in preparation process of graphene, which lays the groundwork for mass production of graphene materials.

Abstract: The alkali heat modification used in coal gangue. And the adsorption effect of MB on original gangue and modified gangue were observed. The results were showed that removal rate of MB was 96.87% and 45.45% by modified gangue and original gangue under the conditions of MB initial concentration 50mg·L-1. The adsorption mechanism was discussed based on Freundlich isotherm model and Langmuir isotherm model. It was proved that MB was easy to be adsorbed by modified coal gangue and the adsorption was belong to monolayer adsorption.The pseudo-second-order kinetic model was best accord to adsorption. And the rate of absorption was control by intra-particle diffusion.

Abstract: In this paper, Fe (NO₃) ₃ 9H₂O and TiO₂ were selected as raw materials. Fe₂O₃/TiO₂ photocatalyst was prepared by the impregnation method. The degradation performance of the photocatalyst for methylene blue solution was studied in detail under the tungsten light source environment. The results showed that Fe₂O₃/TiO₂ had the good photocatalytic properties, and that methylene blue had a higher degradation rate at about 60min. In a certain range of loading, degradation gradually increased with the amount of doped iron. The catalytic performance was high at the basic condition. The degradation rate decreased with the higher initial concentration of methylene blue. The photocatalyst with good performance has been prepared.

Abstract: Surfactant modified bentonite was prepared using cetyltrimethylammonium bromide (CTAB) by a simple ion exchange method, and the organification of bentonite was proved by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron micrographic (SEM). The adsorption of Orange II(OII) dye onto CTAB modified bentonite was carried out. Compared with natural bentonite, the adsorption capacity of CTAB-Bent for OII was greatly enhanced. The adsorption isotherm of OII was in good agreement with the Langmuir equation.

Abstract: The polypropylene (PP) fibers were chosen as substrate materials. Functional fibers containing iron were prepared by UV irradiation-coordination method, and then Pd/Fe bimetallic composite catalytic fibers were prepared by replacement reaction and used for the removement of N-nitrosodimethylamine (NDMA). The effect of monomer concentration, the pH of the reaction system and reaction temperature on NDMA catalytic degradation was investigated. The results indicate that the degradation rate of NDMA can reach 69.97% when the AA monomer concentration is 20%, which is the best catalytic reduction effect of composite catalytic fiber on NDMA. The pH of solution and reaction temperature can not greatly influence the catalytic reduction of NDMA.

Abstract: The montmorillonite supported nanozero-valent iron material (MT-NZVI) was synthesized to remove cadmium (Cd). The results showed that the removal efficiency of MT-NZVI on cadmium was much higher than that of montmorillonite (MT), and the removal efficiency of MT-NZVI on cadmium reduced with the increase of the initial concentration and the pH value, but increased with the increase of the dosage.