Advanced Materials Research Vols. 622-623

Abstract: Removing the carbohydrate of black liquor through biological treatment to converted it into alcohol, as to improve the purity of lignin. Through the study we found that the content of lignin and carbohydrate decreased in the biological purification process. The content of lignin in alkaline black liquor decreases 12.9% after fermentation. And in alkaline sodium sulfite black liquor it decreases 6.4%. Compared with black liquor, the content of total sugar in soda black liquor decreased 77.1%. And in alkaline sodium sulfite it decreases 77.8%. The lignin purity of two kinds of black liquor will improve after the biological treatment. Lignin of alkaline black liquor by biological treatment and organic matter of black liquor ratio increase 28.74%, which increases 29.35% in alkaline sodium sulfite black liquor. The viscosity and CODcr of two kinds of black liquor will reduce after the biological treatment. The relative viscosity of alkaline black liquor after enzymolysis reduces to 1.178, while the relative viscosity of alkaline sodium sulfite black liquor reduces to1.164. The CODcr of alkali black liquor after biological treatment decreases 15.65%; and the CODcr of alkaline sodium sulfite liquor reduces 10.59%.

Abstract: For a large-scale industrial separations and purifications of the lignin in the alkaline pulping, we use aluminum chloride as a catalyst to heat the alkaline pulping black liquor, in order to discuss effects in the nature of high temperature heat treatment process in the alkaline pulping black liquor and aluminum chloride on the nature of alkaline pulping black liquor. The results show that temperature increased and the lignin and carbohydrate content increased and the solids content and pH decreased in the high temperature heat treatment process. When joining the catalyst aluminum chloride, lignin, carbohydrates, solids content and pH value were increased, and increased with increasing amount of aluminum chloride. It proves that the Aluminum chloride plays a big role in the process of the alkaline pulping black liquor heat treatment. It will provide some theoretical basis of the heat treatment of alkaline pulping black liquor.

Abstract: Protein foaming-consolidation method is a facile technique for production of porous materials using egg yolk as pore creating agent. Usage of the yolk in the process offers a number of advantages over other proteins such as egg white and bovine serum albumin (BSA). Various materials were successfully fabricated using this technique. The present paper gives a brief review of the preparation and characterization of the materials through protein foaming-consolidation technique for biomedical application.

Abstract: Crystal of hydroxyapatite (HAp) was grown on silk fibers using simulated body fluid (SBF) at a temperature of 37 °C. Effect of SBF concentrations and sericin protein on the growth of HAp crystals on the silk fiber was discussed. The results showed that sericin protein was an important parameter to induce HAp crystals. Furthermore, the crystal was grown perfectly for both 1.0 and 1.5  standard SBF concentrations but difference in HAp crystal size. Sericin protein may lower nucleation barrier and high surface area to absorb SBF for HAp nucleation. These results may be a new research topic on HAp crystallization using protein as a seed. It may lead to further improvement and applied for many HAp-based biomaterial applications.

Abstract: Palmitoyl cellulose was synthesized under microwave irradiation. The system used was cellulose/ N,N-dimethylacetamide/ LiCl and palmitoylchloride with 4-dimethylaminopyridine (DMAP) as a catalyst. Under microwave irradiation 60secwas sufficient for the completion of reaction, compared to the conventional heating mode. The conditions for reaction under microwave irradiation are: power input of 200watt, 0.5equiv.of DMAPcatalyst andreaction time of 60sec.The adsorption capacity based on Langmuir isotherm is263mg/g which is greater than unmodified cellulose. Material characterization by FT-IR indicates thesuccessful modification of cellulose into palmitoyl cellulose.

Abstract: A novel cyclodextrin (CD) grafted polyvinyl alcohol (PVA) material has been synthesized. Beta-cyclodextrin (βCD) is chemically grafted into PVA via glutaraldehyde (GA) in acidic medium (HCl). The reaction mechanism and the membrane surface grafting are confirmed by Fourier Transform Infrared Spectroscopy (FTIR), modulus of elasticity and contact angle determination. An amount of PVA and βCD are dissolved in a pH 3 HCl solution at 90oC with continuous stirring. Glutaraldehyde was slowly added into the clear solution to effect grafting and crosslinking between the PVA and βCD. It was cooled and allowed to stand overnight to eliminate bubbles formed. The clear PVA-GA-βCD material is casted on a glass plate to form membranes which are peeled off after subsequent drying. The grafted and crosslinked membrane showed peaks in the IR spectra confirming the chemical bonding between PVA, GA and βCD. PVA-GA-βCD membrane is 6% stronger than the physically blended membrane as shown by the increase of its modulus of elasticity. Likewise, a reduction in the hydrophilicity is observed by the newly synthesized membrane as shown by the increase of the membrane’s contact angle.This newly developed material with immobilized βCD may significantly improve the performance of PVA-CD pervaporation membranes by reducing the phase separation phenomenon due to agglomeration of CD in high concentrations as well as preventing βCD from dissolving in aqueous feed. Moreover, this may open new perspective for the development of high performance nanofibers and other nanomaterialssuch as drug delivery system materials and inclusion complexes.

Abstract: In this study, the adsorption capacity of expanded perlite (EP) for benzene at low concentrations in water was investigated after EP was treated with sodium hydroxide (NaOH). IR spectra used to characterize the modified EP showed that there was no bonding between NaOH and the hydroxyl groups on the surface of EP. However, the NaOH provided a basic medium for negatively charged surface oxide ions (-SO-) to form on EP. This fact was corroborated by pH readings of the modification solution. This reduced in pH from 10 to 9 at the end of the reaction which indicated that the hydroxyl OH- groups on the EP underwent deprotonation and hence releases H+ into the solution, and also positive sites on EP adsorbed OH- ions from the base solution. Mahir et al. in their paper Zeta potential of unexpanded and expanded perlite samples in various electrolyte media confirmed that EP has no isoelectric point and exhibits negative zeta potential in the pH range of 2-11. The surface oxides (-SO-) were believed to have given EP it adsorptive potential. Adsorption isotherm values correlated reasonably well with the Langmuir isotherm model and it parameters (qo and K) were obtained using linear regression analysis. A maximum adsorption capacity (qo) value of 19.42 mg/g was achieved.

Abstract: Bees’ treasure “honey” is widely used in food, healthcare and cosmetic sectors. Manuka honey (MH) is a special honey derived by honey bees from the manuka tree. MH exhibits unique antibacterial activity called unique manuka factor (UMF). Honey is consumed mostly as liquid or dry powder. In the present study, MH was electrospun into fibre by blending it with polyethylene oxide (PEO). New ultrafine fibrous morphology of MH will widen its potential field of application and method of end use. The Manuka honey and PEO (MHPEO) blended electrospun fibre mats were observed under SEM to study fibre morphology. The effects of various solution parameters like MH/PEO ratio, viscosity, conductivity, surface tension etc. on MHPEO electrospun fibre morphology are also established. Effect of process parameters like feed rate, needle to collector distance (NTCD), applied voltage (app. volt.) etc. on 15% MHPEO (15MHPEO) fibre morphology are also determined. SEM observation revealed that smooth and unmerged fibres were obtained from PEO solution. More merged and thicker MHPEO fibres were obtained with increase in MH content as well as feed rate and decrease in app volt as well as NTCD. Electrospun mats were analysed using FTIR and DSC. FTIR curves showed characteristic peaks related to both PEO and MH in 15MHPEO mat. DSC curves showed shift of melting point towards lower temperature with increase in MH proportion. UV-vis spectra of PEO and MHPEO solutions were also studied.

Abstract: Removed at authors request.

Abstract: The composite of methoxy polyethylene glycol (mPEG) and poly(lactic-co- glycolic acid) (PLGA) thermosensitive hydrogel mixed with different mass raio of hydroxyapatite and β-tricalcium phosphate (β-TCP) were used as bone graft substitutes. The physical properties of a series of composite gels, including the critical micelle concentration (CMC), particle sizes, zeta potential, rheological behavior, morphology of composite gels, and sol–gel transition, were characterized in vitro. These composite gels could form a gel at body temperature and could be controlled easily at room temperature. During the in vitro degradation process, composite gels demonstrated a slight decrease in pH value, a slower degradation rate, less toxicity, and a higher cell survival rate. The biocompatibility of the composite gels was validated by hemolysis test. In vivo animal studies demonstrated both radiographic and gross bone union when the ratio of HAP/ β-TCP was 7:3.