黏结剂对含碳球团强度影响的试验研究及机理分析

含碳球团的强度是制约含碳球团在低碳炼铁领域应用的主要原因之一。文章针对含碳球团强度难以满足装备要求的问题,研究了膨润土、硅酸钠、HPMC等3种黏结剂对冷压含碳球团落下强度和抗压强度的影响,并对黏结剂成球机理及生球微观结构进行分析。研究结果表明:球团强度随着铁矿颗粒粒径降低而降低,随着煤粉颗粒粒径降低而升高;随着膨润土、硅酸钠、HPMC用量的增加,含碳球团的抗压强度及落下强度均表现为升高趋势。对球团的微观结构形貌用SEM分析发现,膨润土在铁矿颗粒表面附着并呈聚集状,而HPMC可浸入铁矿周围或内部,可显著提高含碳球团的落下强度与抗压强度。

Formulation and evaluation of anti-asthmatic drug montelukast in mucoadhesive buccal patches

Objective: To formulate and evaluate anti-asthmatic drug montelukast in mucoadhesive buccal patches. Methods:Buccal patches were formulated by using different hydrophilic polymers by solvent casting technique. Buccal patches were evaluated by seven physical appearances, in addition toin vitro drug release study. Results: All patches were uniform and translucent, and had smooth surface. In vitro release studies were conducted for montelukast buccal patches proved that release in the range of 75.26%-92.30% in 8 h. Emission of montelukast from all patches simulated zero order and diffusion mechanism. Finally it can be concluded that F3, F15 and F16 are the best formulation. Conclusions: The investigation concluded that patch of 5 mg of montelukast sodium were formulated by using sodium alginate with sodium carboxy methyl cellulose, hydroxy propyl methyl cellulose K100M with sodium carboxy methyl cellulose, and hydroxy propyl methyl cellulose K100M with sodium alginate (F3, F15 and F16 formulations) were the best formulations.