Preparation and Characterization Analysis of Hydroxyapatite/ Gelatin Composite

1Introduction Scaffoldmaterialsplayaveryimportantroleintissue engineering,whichisaimedtoprovidereplacementsfor damagedorlosttissuesandorgans.Naturalbone,which formsinapre organizedbiopolymericmatrixthroughthe processofbiomineralization,exhibitsanexcellent…     

Experimental Study on Polymer Artificial Bone with HA Coated and Fiber Liners

1Introduction HA(hydroxyapatite)wasakindofbioactiveceram ics,whichhadexcellentbiocompatibilityandtissueaffin ityinthatitscomponentsweresimilartothoseofhuman bone[1].Soitwasthebestknownhumanbonesubstitute,andunprecedentedeffecthadbeenharvestedinrecenttwo d…     

一维ZnO纳米结构的电子场发射研究

在大量制备一维ZnO纳米结构的基础上,研究了这些纳米结构的场发射性能。对于四角状ZnO纳米结构,获得1.0m Ac/m2的电流密度只需要4.5V/μm的电场;对于线状Z nO纳米结构,获得1.0mAc/m 2的电流密度需要6.5V/μm的电场。由于其特殊的结构,四角状ZnO一维纳米结构在真空电子器件方面有很好的应用前景。     

Biowaste-derived hydroxyapatite reinforced with polyvinyl pyrrolidone/aloevera composite for biomedical applications

The present investigation focuses on the synthesis of crabshell-derived hydroxyapatite (CS-HAP)/ water-soluble synthetic polymer—polyvinylpyrrolidone(PVP)/aloevera(AV)—a natural biopolymer, as a composite for enhanced mechanical, antibacterial and biocompatible properties. The reinforcement of polymer has a significant function in increasing the mechanical property of the composite, whereas the incorporation of AV improves the antibacterial and biocompatibility. Phase composition, morphology, mechanical property, and hydrophilicity of CS-HAP/PVP/AV biocomposite with different concentrations of PVP and AV were examined by Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), scanning electron microscopy with energy dispersive X-ray (SEM-EDX), Vickers microhardness tests, contact angle, respectively. Furthermore, the antibacterial efficiency of the composite is assessed using Escherichia coli (E coli) and Staphylococcus aureus (S aureus). The biocompatibility of HOS MG 63 cells on the CS-HAP/PVP/AV composite is evaluated by MTT assay test. The obtained results evidence that the as-synthesized composite have appropriate mechanical, antibacterial and biocompatible properties. Overall, the combination of mechanical property of PVP, antibacterial and biocompatible property of AV in CS-HAP/PVP/AV, makes the composite a potential therapeutic material for various biomedical applications.     

短棒状纳米羟基磷灰石的湿法合成及表征

通过简单湿法合成制备了短棒状纳米羟基石颗粒，粉体在不同的温度下进行了热处理，并用红外光谱、透射电镜及X射线衍射等实验手段对组织、结构及热稳定性进行了表征。研究表明，将适当比例的（NH4）2HPO4和Ca（NO3）2晶体混合、振荡、陈化后提纯、烘干，可制备出长约30－40nm，直径约10－20nm的短棒状纳米羟基灰石颗粒，这种颗粒结构与通常的针状结构相比更接近于人体骨磷灰石（长约40－60nm，宽约20nm）；该颗粒具有较好的热稳定性，600℃以下热处理后，颗粒结构、尺寸和形貌基本不变，分散性较好；900℃热处理后，颗粒明显长大并严重团聚。     

Novel one-step formed composite reinforcement of "Spider web like" SiCnw networks and "Z-pins like" SiC rods for ablation resistance improvement of C/C-ZrC-SiC

A novel composite reinforcement with horizontal multilayer "Spider web like" SiC nanowire networks and vertical interconnected "Z-pins like" SiC rods was designed and prepared by facile one-step figuration. The linear ablation rate of "Spider web like" SiC nanowire networks and "Z-pins like" SiC rods collectively reinforced C/C-ZrC-SiC composites at 2610 ± 20 ℃ was 0.4 ± 0.03 μm/s with a 74.19 % reduction. The improved ablation resistance was attributed to a denser gradient oxide layer composed of central ZrO₂ layer, transitional ZrO₂-SiO₂ layer and marginal SiO₂ layer generated under the initial sticky net effect from SiCnw networks and subsequent oxide compensation from "Z-pins like" SiC rods.     

生物陶瓷内部成孔与贯通方式的研究

多孔羟基磷灰石（HA）陶瓷内部结构满足细胞向内部渗透、迁移、粘附和生长的条件。实验探讨了HA陶瓷内部成孔与孔道连结的机理与技术，采用添加制孔剂和固化纤维2种方法制备系列样品，测算了样品气孔率，并对微观结构进行扫描电镜观察，最终确定可人工调控内部结构的HA陶瓷成孔与贯通技术。     

无氟防龋体系浅析

牙膏无氟防龋体系应用的防龋材料主要有纳米级羟基磷灰石（HAP）、免疫球蛋白（IgY）和中药如两面针、厚朴、茶多酚和蜂胶等.纳米级羟基磷灰石可以使脱矿的牙釉质再矿化,提高牙釉质抗龋能力;免疫球蛋白对变形链球菌和牙菌斑的形成有较好的抑制作用.检测试验或临床结果表明,两面针、厚朴、茶多酚和蜂胶等中药对致龋菌和牙菌斑的形成的抑制效果也比较好,这些都可以组成效果比较好的无氟防龋体系.     

多孔羟基磷灰石生物陶瓷的进展

多孔羟基磷灰石生物陶瓷是一种性能优异的人体硬组织修复材料，在植入界面后它具生物降解性，置入体内能逐步参与代谢以至最终与人体骨结合成一体。本文在综合大量国内外文献的基础上，阐述了多孔羟基磷灰石生物陶瓷的性质、研究和发展。     

内部连接的球形多孔羟基磷灰石支架的制备

采用高分子模板,通过注浆成型制备了球形孔结构的羟基磷灰石(hroxyapatite,HA)支架,研究了支架的微观结构、压缩强度和相容性.结果表明:改变工艺参数可以控制高分子模板中球体间胶黏面的大小,控制所制备的HA多孔体孔内连接的尺寸.制备的支架具有开口、均匀而内部连通的多孔结构,当孔径为200μm、孔隙率为65%时,压缩强度可达8MPa左右.体外生物模拟实验表明:多孔结构HA支架有很好的相容性.随多孔球体孔隙率和尺寸的增加,支架的细胞吸收率逐步增加.