Lonidamine Solid Dispersions: In Vitro and In Vivo Evaluation

ABSTRACT

Solid dispersions of lonidamine in PEG 4000 and PVP K 29/32 were prepared by the spray-drying method. Then, the binary systems were studied and characterized using differential scanning calorimetry, hot stage microscopy, and x-ray diffractometry. In vitro dissolution studies of the solid dispersed powders were performed to verify if any lonidamine dissolution rate or water solubility improvement occurred. In vivo tests were carried out on the solid dispersions and on the cyclodextrin inclusion complexes to verify if this lonidamine water solubility increase was really able to improve the in vivo drug plasma levels. Drug water solubility was increased by the solid dispersion formation, and the extent of increase depended on the polymer content of the powder. The greater increase of solubility corresponded to the highest content of polymer. Both the solid dispersions and the cyclodextrin complexes were able to improve the in vivo bioavailability of the lonidamine when administered per os. Particularly, the AUC of the drug plasma levels was increased from 1.5 to 1.9-fold depending on the type of carrier.     

太钢热连轧活套控制系统的设计与实现

介绍了液压活套的工作原理和控制特点,确定了活套微张力自动控制系统的总体设计思想.全自动液压活套张力控制能够实现机架间稳定控制,具有非常好的实用价值,在同类行业中也具有较大的推广意义.     

注塑模具高速切削抛光复合工艺

如今模具的重要性日益凸显，模具质量和制造水平都亟待提高。高速加工技术是先进制造技术的共性基础技术，其插补功能强大、配套完善、控制可靠、可自动换刀，尤其适用于自由曲面的加工。本文从模具材料，模具复杂型面加工，模具制造周期及抛光，高速加工在我国的应用以及国内外的研究进展等方面结合高速加工的特点综合考虑，探讨了高速切削实现注塑模具切削及抛光同机复合工艺的优势和可能性。     

铝合金叶轮高效加工工艺研究

从工艺路线的调整入手,介绍了所做的各项工艺摸底试验结果,针对某压气机叶轮生产进行了工艺高效化改进,阐述了出现的各种问题的处理方法,取得了较高的经济效益.     

塑料模具光整加工技术及其合理选用

介绍了几种常见的塑料模腔表面抛光技术，针对塑料模的加工特点，结合模具光整加工的新进展，分析了如何合理选用塑料模具型腔光整加工技术。     

摩托车曲柄锻模高速加工

介绍了锻模的高速加工，论述了实施高速加工的支撑技术。     

高速加工中心主轴系统动力学建模及优化设计

建立了DMU-70V五轴数控高速加工中心主轴-夹具-刀具系统的有限元模型，并利用动态测试的方法对有限元计算结果进行验证；以提高低阶固有频率作为动态优化目标函数，对主轴系统进行了优化设计。     

A force control high-order single-step-β method (HSM) for substructure pseudo-dynamic testing

This paper proposes a new technique which introduces the high-order single-step-β method(HSM)into the experimental study on the substructure pseudo-dynamic testing(SPDT).The technique is based on the proposed concept of equivalent shear stiffness which can meet the requirement of the HSM algorithm.A study is done to theoretically validate the technique by the numerical analysis of two-storey shear building structure,in comparison of the proposed substructure pseudo-dynamic testing algorithm with the central difference method(CDM).Then,a full-scale SPDT model,the three-storey frame-supported reinforced concrete short-limb masonry shear wall structure,is designed and tested to simulate the seismic response of the corresponding six-storey structure and verify the proposed force control HSM technique.Meanwhile,the techniques of both stiffness correction and force control are suggested to control algorithmic error,control error and measurement error.The results indicate that the force control HSM can be used in the full-scale multi-degree-of-freedom(MDOF)substructure pseudo-dynamic testing before descent segment of structure restoring force properties.     

基于VERICUT的虚拟机床建模技术研究

虚拟机床建模是数控加工仿真的基础,通用准确的建模方法是保证仿真高效的要求之一.简介虚拟制造软件VERICUT的功能模块,分析虚拟机床的建模过程,总结不同机床通用性的建模方法,分析建模中的关键性问题;并基于VERICUT的建模技术论述应用其进行数控机床建模的流程.最后应用此建模方法以五轴高速加工机床HSM600U为实例,详细介绍其在VERICUT中的建模过程.该方法有良好的通用性,适合作为其他机床建模的参考.     

基于RBF神经网络的难加工材料高速铣削力预报研究

切削力的预报是切削加工的重要研究方向.文中运用RBF神经网络建立了铣削力预测模型,将预报结果与试验真值以及由回归分析处理的结果进行对比验证,结果表明此方法可行,为切削参数优化和数据库研制提供了依据.