In this paper, super absorbent polymer was prepared through graft copolymerization by cellulose and acrylic acid (AA), acrylamide (AM), and butyl methacrylate (BMA) and its properties were determined. It showed that optimum reaction condition is the amount of cellulose, AA, AM and BMA is 10g, 4.5g, 2g and 1.5g respectively, the amount of initiator (potassium persulfate) and N,N'-methylene bisacrylamide is 0.01g and 0.012g, the pH value of AA after neutralization is 7. The water absorbency to distilled water, tap water and salt solution of super absorbent polymer which was prepared under these conditions is 770g/g, 113g/g and 86g/g respectively. The water retention rate of super absorbent polymer gel drops to 3% needs 130 hours under natural condition. It was expected that super absorbent polymer can be used for preservation processing of fruits.

Using sodium hydroxide as its alkali catalyzer, 3-chloro-2-hydroxypropyl trimethyl ammonium chloride as its quaternary agents, cationic starch with high degree of substitution was made by semi-dry process. The prepared cationic starch contains quaternary ammonium groups by the infrared spectrum analysis. From the scan electron microscope pictures of starch and cationic starch, cationic starch can be clearly seen to have substituted the quaternary ammonium salt groups and the structure of mutual penetration of flexible quaternary ammonium salt groups and rigid starch has formed. The tensile strength of paper improved by cationic starch with high degree of substitution is far more than that by cationic starch with low degree of substitution and poly diallyl dimethyl ammonium chloride. The scan electron microscope pictures of the surface and fracture of the paper show that the distribution of the paper fiber which added additives are apparently tight and uniform and there are many small fibers obtained on the surface of paper samples. The fibers of the paper sample which added additives have more fracture themselves and have less extraction entirely. It indicates that the force between fibers has been strengthened by cationic starch additive.

The application of nanosilica in coating of art paper and ink-jet paper is studied. The results show that when nanosilica is used in art paper coating, the dispersity and flowability of the art paper coating are excellent. The surface strength, smoothness and gloss of the paper coated with art paper coating with nanosilica are improved and its yellowing rate is decreased. When nanosilica is used in ink-jet paper coating, the dispersity of prepared ink-jet paper coating is of better, the coated paperboard with ink-jet paper coating with nanosilica is of ink transfer larger, K&N value higher and whiteness higher. The smoothness and gloss of paperboard coated with ink-jet paper coating with silica are improved. The combination application of more kinds of adhesives improves the print gloss of paperboard coated with ink-jet paper coating with silica.

A three-dimensional finite element model of the spine T12-S1 segment was developed and used to investigate biodynamics characteristics of the human lumbar spine. The T12-S1 model was carefully built including spinal vertebrae, intervertebral discs, and ligaments so as to approach the real human spine. Finite element modal analysis was carried out to obtain vibration modes and resonant frequencies of the spine. The analytical results indicate that the vertical resonant frequency of the spinal T12-S1 segment with a mass of 40 kg on the top vertebra is 7.68 Hz. The vertical resonant frequencies of spine motion segments decrease with the number of spine motion segments increasing. The tissue injury, such as disc denucleation and removal both of facet articulations and their capsular ligaments may decrease the resonant frequencies of spine in different extent. The denucleation makes larger influence on vertical resonant frequencies than facetectomy does. The denucleation is more harmful to the facet articulations under whole body vibration. The dynamic characteristics of the T12-S1 model accords with the actual human spine, and it is useful for the relative studies of the human spine, such as biomechanical characteristics, vibration-related injury mechanism of the human spine, and development of vibration-related mechanical products.

Strengthening agent of cationic polyacrylate emulsion was prepared through semi-continuous seeded pre-emulsion processes. By single factor experiment, investigated the factors which influence on properties of emulsion, such as the proportion of hard and soft segment monomer, the dosage of AM, DMDMAC, emulsifier and initiator, reaction time and temperature, addition time and other factors. The results show that the emulsion has a good enhancement when the monomer ratio of St: MMA: BA is 2:1:3, initiator dosage is 0.7%, the dosage of emulsifiers, AM and DMDMAC are 6%, the amount of protective colloid is 0.3%. Compared to the strength performance between paper with added emulsion and blank paper, find that the performance of paper with added emulsion polymer gets different improves: paper quantitative increase 4.08%, folding strength degree improves 66.67%, tearing degree improves 356.52%, ring compressive strength improves 50.00%, tensile strength improves 44.11%, and bursting strength improves 50.88%