基于表面生物学改性的多孔状二氧化钛/磷灰石复合薄膜的制备

在钛合金表面采用微弧氧化得到一层多孔状的具有生物活性的二氧化钛 ,经随后水热处理可形成羟基磷灰石薄膜 ,提高钛合金表面的生物学性能 .用SEM ,XRD ,EDX分析了薄膜的组织、结构和化学组成 .同时考察了微弧氧化得到的二氧化钛膜的生物活性 .结果表明 :在室温条件下从含钙、磷离子的电解液中在钛合金基体上微弧氧化得到一层二氧化钛薄膜 ,蒸汽处理后得到具有生物活性的二氧化钛 /羟基磷灰石复合薄膜 .该膜多孔均匀 ,且生物活性高 ,有利于骨组织的吸附和生长 .

液体硅橡胶功能改性及其医学应用研究进展

液体硅橡胶具有良好的化学稳定性和生物相容性,广泛应用于医疗及医疗器械领域,然而,在实际应用中存在机械支撑强度不足、稳定性不足以及易引发感染等缺陷。因此,提升液体硅橡胶的机械强度、抗菌性、化学稳定性和生物活性是首先要解决的问题。研究发现,将各种纳米填料添加到液体硅橡胶基质中,不仅可以提高材料的力学性能,还可以将其电学和抗菌性能提高到一个较好的水平。简要总结了液体硅橡胶的分类、构建及性能改进方式,重点阐述了液体硅橡胶在医学领域应用过程中的研究现状及目前所面临的瓶颈问题。液体硅橡胶生物医学功能改性研究有望提升纳米材料在液体硅橡胶中的分散性并改善其抗菌性、稳定性和导电性,提升液体硅橡胶的应用价值并拓展其应用场景。

Diester Derivatives from Chemically Modified Waste Cooking Oil as Substitute for Petroleum Based Lubricating Oils

In order to provide a new way for waste cooking oil(WCO) resource utilization, several diester derivatives were obtained from WCO through a three-step chemical modifications, viz.: transesterification, epoxidation and oxirane ring opening with carboxylic acids. The effects of the chain length of side chain groups on the viscosity, acid value, low temperature fluidity, thermo-oxidative stability, tribological properties and surface tension of diester derivatives were investigated. The results showed that increasing the chain length of side chain groups had a positive influence on the viscosity, viscosity index, acid value, pour point, friction coefficient and wear scar diameter along with a negative influence on the oxidation onset temperature, volatile loss, insoluble deposit, maximum non-seizure load and surface tension. These diester derivatives exhibited improved physicochemical and tribological properties that make themselves promising environmentally friendly biolubricant basestocks.

Vitamin E-derived copolymers continue the challenge to hemodialysis biomaterials

Improving material biocompatibility has been a continu-ous effort and remains a major goal of dialysis therapy. In this respect, vitamin E-modified copolymers have been used to produce a generation of biomaterials that has offered new clinical challenges and the chance of further improving the quality of synthetic hemodialyser membranes. This mini review article describes the evo-lution of these copolymers that only recently have been adopted to develop new vitamin E-modifed polysulfone hemodialysers. Biomaterial characteristics and clinical aspects of these membranes are discussed, starting from the most recent contributions that have appeared in the literature that are of interest for the community of nephrology and dialysis specialists, as well as bioma-terial scientists.

单晶硅阳极氧化层表面骨状磷灰石的体外诱导沉积

在磷酸钠碱性电解质中对单晶硅(100)进行阳极氧化处理,并将阳极氧化处理后的样品在模拟体液(simulated body fluid,SBF)中浸泡以考察其体外诱导骨状磷灰石沉积能力。用扫描电子显微镜观测体外浸泡前后样品的表面形貌,用电子能谱仪和X射线衍射仪研究阳极氧化后与体外浸泡不同时间后样品表面的成分。结果表明:单晶硅在10%的磷酸钠电解质中于5～20mA/cm2阳极氧化后,其表面原位形成火山口状结构,在SBF中浸泡1d后有磷灰石在单晶硅的阳极氧化层表面成核,浸泡6d后诱导形成了纳米骨状缺钙磷灰石层,体现出良好的体外诱导活性,表明阳极氧化处理是一种有希望应用于改善生物学与医学用单晶硅表面生物相容性的有效途径。

Ionic liquids: Efficient solvent and medium for the transformation of renewable lignocellulose

Carbon-enriched lignocelluloses are regarded as the perfect alternative for nonrenewable fossil fuel, and have a great potential to alleviate the increasing energy crisis and climate change. However, the tightly covalent structure and strong intra and in- ter-molecular hydrogen bonding in lignoceUulose make it high recalcitrance to transformation due to the poor solubility in wa- ter or common organic solvents. Dissolution and transformation of lignocellulose and its constituents in ionic liquids have therefore attracted much attention recently due to the tunable physical-chemical properties. Here, ionic liquids with excellent dissolving capability for biomass and its ingredients were examined. The technologies for lignocellulose biorefining in the presence of ionic liquid solvents or catalysts were also summarized. Some pertinent suggestions for the future catalytic conver- sion and unitization of this sustained carbon-rich resource are proposed.