不同浓度掺镁透钙磷石骨水泥修复骨质疏松家兔骨缺损及BMP-2表达的研究

健康家兔36只,进行骨质疏松造模后随机分为空白对照组、透钙磷石组(DCPD组)、掺镁6.67%组、掺镁26.67%透钙磷石组,在家兔双侧前腿桡骨中段制作骨缺损,术后每组动物分别于4、8、12周各处死3只,观察组织切片中BMP-2表达情况与X线片显示骨缺损修复状况。免疫组化结果显示同组不同时期比较,4周时BMP-2表达最高,8周时较4周时减弱,12周时阳性表达最弱。同一时期组间比较掺镁6.67%组阳性表达最强。在骨质疏松家兔桡骨骨缺损修复中,掺镁6.67%透钙磷石组成骨效果较其他组显著,同时期组间比较BMP-2阳性表达最强。     

不同浓度掺镁透钙磷石骨水泥修复骨质疏松家兔骨缺损及BMP-2表达的实验研究

健康家兔36只,进行骨质疏松造模后随机分为空白对照组、透钙磷石组(DCPD组)、掺镁6.67%组、掺镁26.67%透钙磷石组,在家兔双侧前腿桡骨中段制作骨缺损,术后每组动物分别于4、8、12周各处死3只,观察组织切片中BMP-2表达情况与X线片显示骨缺损修复状况。免疫组化结果显示同组不同时期比较,4周时BMP-2表达最高,8周时较4周时减弱,12周时阳性表达最弱。同一时期组间比较掺镁6.67%组阳性表达最强。在骨质疏松家兔桡骨骨缺损修复中,掺镁6.67%透钙磷石组成骨效果较其他组显著,同时期组间比较BMP-2阳性表达最强。     

生物医学钛合金微弧氧化涂层的表面特征

通过在含有钙盐、磷盐的的电解液中对Ti-6Al-4V合金进行微弧氧化处理,在钛合金表面制备了含钙、磷元素的陶瓷层.采用扫描电镜(SEM)、X射线衍射仪(XRD)和能谱仪分析了涂层的形貌、相及元素组成.结果表明,Ti-6Al-4V合金表面的微弧氧化涂层是一种含钙磷元素、多孔、与基体结合牢固、具有陶瓷特性的混合物,其主要组成相为二氧化钛.经过六偏磷酸钠-乙酸钙工艺处理后的试样涂层中含有α-Ca(PO3)2、CaTiO3相.从物相的组成考虑,经过六偏磷酸钠-乙酸钙工艺处理后的涂层的生物活性更好.     

生物医学钛合金微弧氧化涂层的表面特征

通过在含有钙盐、磷盐的的电解液中对Ti-6Al-4V合金进行微弧氧化处理,在钛合金表面制备了含钙、磷元素的陶瓷层。采用扫描电镜(SEM)、X射线衍射仪(XRD)和能谱仪分析了涂层的形貌、相及元素组成。结果表明,Ti-6Al-4V合金表面的微弧氧化涂层是一种含钙磷元素、多孔、与基体结合牢固、具有陶瓷特性的混合物,其主要组成相为二氧化钛。经过六偏磷酸钠-乙酸钙工艺处理后的试样涂层中含有α-Ca(PO3)2、CaTiO3相。从物相的组成考虑,经过六偏磷酸钠-乙酸钙工艺处理后的涂层的生物活性更好。     

碳酸锶渣中锶的氯化铵浸出回收工艺

采用氯化铵做浸煮剂,从锶渣中回收氯化锶.通过正交实验及单因素实验分析了锶渣粒径、反应时间、液固质量比、n(NH4Cl)/n(Sr)对锶转化率的影响.研究结果表明,最佳工艺条件为锶渣粒径0.054 mm、反应时间2 h、液固质量比3.3、n(NH4Cl)/n(Sr)为3.8.从锶渣中回收氯化锶的回收率可达96%,转化过程符合分形动力学特征.     

医用可降解镁合金表面磷酸盐涂层研究进展

综述了医用镁合金表面磷酸盐涂层的制备工艺和特点,主要介绍了医用镁合金表面几种Ca-P(包括二水磷酸氢钙、磷酸三钙和羟基磷灰石)转化涂层及其(F、Sr和Ce)元素掺杂涂层的腐蚀性能和生物学特性,并简要提出了医用可降解镁合金表面磷酸盐转化膜工艺涉及的环境、工艺稳定性问题和研发策略。     

Mn掺杂的Cu-Co堇青石整体催化剂催化燃烧醋酸甲酯

采用浸渍法制备Mn掺杂的Cu-Co整体催化剂,通过X线衍射(XRD)、N2吸附-脱附、扫描电子显微镜(SEM)等手段对催化剂进行表征,并以醋酸甲酯催化燃烧为探针反应,考察涂层中CeO2与Zr0.5Ti0.5质量比、Mn掺杂量、焙烧温度等条件对催化剂性能的影响。结果表明:涂层中CeO2与Zr0.5Ti0.5质量比为2∶1,Mn掺杂量为6%,n(Mn)∶n(Cu)∶n(Co)为2.2∶1∶2,焙烧温度为500℃时,催化剂具有最佳的活性。当醋酸甲酯质量浓度为9 g/m3,质量空速为12 L/(g.h)时,醋酸甲酯转化率达到90%的反应温度为256℃。     

医用可降解Mg-3Zn-0.5Sr合金耐蚀性及细胞毒性

采用仿生法在Mg-3Zn-0.5Sr合金表面制备涂层,通过SEM,EDS和XRD分析表征涂层形貌和结构;采用电化学实验和浸泡腐蚀实验来研究涂层对合金降解速率的影响;采用生物毒性实验验证有无涂层Mg-3Zn-0.5Sr合金的毒性等级.实验结果表明:在Mg-3Zn-0.5Sr合金表面可以沉积致密的羟基磷灰石(HA)涂层,厚度约为30~40μm,HA涂层可以有效地降低Mg合金的降解速率;在体积分数为25%的有无涂层合金浸提液中培养细胞4d,细胞相对增值率均超过100%,有无涂层合金的细胞毒性均为0级.     

水泥对脱硫石膏性能影响的试验研究

为改善脱硫石膏的性能,使其在建筑工程中应用更为广泛。通过对不同水泥掺量的石膏进行抗压强度和抗折强度试验,探究石膏强度与水泥掺量的关系;并通过扫描电镜实验(SEM)和X射线衍射实验(XRD)对单掺水泥石膏强度变化的微观机制进行分析。研究结果表明:水泥掺入脱硫石膏后可以一定程度上改善脱硫石膏的力学性能,提高脱硫石膏的强度。通过微观机理分析发现,水泥-石膏混合体系中会产生钙矾石,由于钙矾石的膨胀以及硅酸钙水化后生成的水化硅酸钙凝胶填充于石膏孔隙,使石膏趋于密实,从微观上解释了石膏强度的增长机制。但由于钙矾石的膨胀具有双重作用,因此存在水泥的最经济掺加量,实验研究确定脱硫石膏中水泥的最经济掺加量为10%。     

钛白粉与硬硅钙石复合隔热外墙涂料隔热性能研究

采用金红石型钛白粉和超轻硬硅钙石型硅酸钙为隔热功能填料,制备复合隔热外墙乳胶涂料。研究了钛白粉掺量和硬硅钙石掺量对涂层隔热性能的影响,以及钛白粉和硬硅钙石协同作用对隔热性能的影响。研究表明:分别添加钛白粉和硬硅钙石均能提高涂层的隔热性能;复合添加钛白粉和硬硅钙石能进一步提升涂层隔热性能,复合涂层的热反射率可达80.54%,超过M IL-E-46117标准中热反射率高于75%的要求。     

Ti6Al4V钛合金微弧氧化工艺研究

采用直流稳压电源,选用3种不同PH值的碱性微弧氧化电解液,在Ti6Al4V钛合金表面制备微弧氧化膜层;应用扫描电子显微镜分析微弧氧化膜层形貌特征。结果表明,钛合金微弧氧化膜层表面凹凸不平,带有微米级和亚微米级的孔洞,孔洞周围呈现火山丘状形貌特征;微弧氧化电解液PH值越大,火花放电时间越长;在给定电压条件下,电解液PH值越大,微弧氧化膜层厚度越大。     

乙醇对电沉积磷酸钙盐涂层的影响

采用电化学方法于常温下进行钛金属基底上磷酸钙盐的沉积，通过添加一定量的乙醇于电沉积溶液中，在一定程度上解决了电沉积过程中析氢反应对磷酸钙盐沉积的影响．同时，考察了恒电位沉积时间对磷酸钙盐涂层质量的影响。在一定温度下于碱液中处理后获得的羟基磷灰石(HA)涂层的形貌和结构分别用扫描电子显微镜(SEM)和X-射线衍射仪进行了表征；用粘结拉伸法测量了涂层的界面结合强度达7．18Mpa，并在模拟生物体液中考察了生物活性以及电化学腐蚀性能。     

热喷涂用Ni/WC金属陶瓷粉的化学镀制备

对非金属化学镀镍活化方法的研究进行了概述，提出了以盐为活化剂的直接活化新工艺．采用这种活化法，首先在碳化钨颗粒表面吸附上具有催化活性的Cl^-，然后进行化学镀镍，得到均匀、致密、完整的Ni-P合金包覆层，并对镀镍合金层成分进行了能谱分析以及镀覆层形貌进行扫描电镜观察．结果表明，镀覆层除镍、磷元素外，实验过程中未引入杂质元素，镀层为典型的低磷层形貌。     

High-temperature oxidation resistance of ceramic coatings on titanium alloy by micro-arc oxidation in aluminate solution

Ceramic coatings with aluminum titanuate (Al₂TiO₅) were prepared on Ti–6Al–4V alloy using pulsed bi-polar Micro-arc Oxidation (MAO). The micromorphology and phase composition of the micro-arc-oxidition ceramic coatings on the titanium alloy were characterized by X-ray powder diffraction (XRD), and scanning electron microscopy (SEM) respectively. The results revealed that the distinct discharge channels and pores on the surface of the micro-arc-oxidition coatings appeared, and these channels were connected in the molten state. The electrolyte concentration was inversely proportional to the coating hardness; additionally, the coating prepared with sodium aluminate and sodium hypophosphite concentrations of 4 ?g/L and 0.5 ?g/L, respectively, was the most refined after high-temperature sintering, and it was demonstrated to better prevent oxidation. Increasing the electrolyte concentration coincided with fluctuating coating thermal shock resistance. The thermal shock resistance of the coating respectively prepared with sodium aluminate, and the sodium hypophosphite concentrations of 4 ?g/L and 0.5 ?g/L was the highest. Additionally, the high-concentration coatings performed significantly better than the low-concentration coatings. The oxidation resistance of the coating samples was also significantly higher than that of the TC4 titanium alloy substrate. The adhesion strength between the coatings and the substrate with and without the sealing treatment was measured by tensile tests. Then, the high-temperature oxidation performance of the coating samples with and without the sealing treatment was investigated by conducting a high-temperature oxidation experiment at a calcinating temperature of 500 ?°C. The results indicate that the adhesion strength between the coatings and substrate was high for the as-prepared and sealed micro-arc oxidation samples regardless of whether they were calcined. The high-temperature oxidation mass increase curves for the sealed and unsealed coating samples calcined at 500 ?°C for 500 ?h revealed that the high-temperature-oxidation-induced mass increase of the coating samples sealed with a sodium silicate solution was much lower than that of the titanium alloy substrate. Thus, the sealing treatment significantly improved the high-temperature oxidation resistance of the TC4 titanium alloy. Lastly, the high-temperature oxidation behavior at 500 ?°C was analyzed and discussed.     

不同变质剂对4032铝合金变质效果的影响

研究Sr与不同变质剂复合添加对4032铝合金组织及性能的影响.通过组织观察、扫描电镜观察、能谱分析和力学性能测试发现:在几种不同的变质体系中,Sr与Na盐复合变质后的组织和性能最好;Sr+其他元素复合变质的针孔率低于Sr单独变质处理的针孔率,其中以Sr+Na盐变质的针孔率最低;共晶型铝硅合金添加Sr和Na变质组织呈亚共晶状态,而经P变质后组织呈过共晶状态.     

AZ91D镁合金在不同电解液体系中的微弧氧化行为

在3种不同电解液体系中,对AZ91D镁合金表面分别进行微弧氧化处理而得到氧化物陶瓷膜,采用扫描电子显微镜(SEM)、X射线衍射仪(XRD)对其表面形貌和相组成进行分析,利用划痕仪测试氧化膜与镁合金基底的结合强度,并用电化学工作站分析氧化膜在模拟人体体液中的腐蚀性能.结果表明:在不同电解液体系中所获氧化膜的表面结构和组成不同;随着氧化时间的延长,微弧氧化涂层与基底的结合力先逐渐增加而后趋缓;微弧氧化处理可明显提高AZ91D镁合金的耐腐蚀性能.     

In vitro degradation and biocompatibility of Mg-Nd-Zn-Zr alloy

In this study,in vitro degradation and biocompatibility of Mg-Nd-Zn-Zr(NZK) alloy were investigated to determine its suitability as a degradable medical biomaterial.Its corrosion properties were evaluated by static immersion test,electrochemical corrosion test,scanning electron microscopy(SEM),and energy dispersive spectroscopic(EDS) analysis,and in vitro biocompatibilities were assessed by hemolysis and cytotoxicity tests.Pure magnesium was used as control.The results of static immersion test and electrochemical corrosion test in simulated body fluid(SBF) demonstrated that the addition of alloying elements could improve the corrosion resistance.The hemolysis test found that the hemolysis rate of calcium phosphate coated NZK alloy was 4.8%,which was lower than the safe value of 5%.The cytotoxicity test indicated that NZK alloy extracts did not significantly reduce MC3T3-E1 cell viability.Hemolysis test and cytotoxicity test display excellent hemocompatibility and cytocompatibility of NZK alloy in vitro.Our data indicate that NZK alloy has excellent biocompatibility and thus can be considered as a potential degradable medical biomaterial for orthopedic applications.     

Fabrication and characterization of anodic oxide films on a Ti-10V-2Fe-3Al titanium alloy

Anodic oxide films of the titanium alloy Ti-10V-2Fe-3Al in ammonium tartrate electrolyte without hydrofluoric acid or fluoride were fabricated. The morphology, components, and microstructure of the films were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and Raman spectroscopy. The results showed that the films were thick, uniform, and nontransparent. Such films exhibited sedimentary morphology, with a thickness of about 3 μm, and the pore diameters of the deposits ranged from several hundred nanometers to 1.5 μm. The films were mainly titanium dioxide. Some coke-like deposits, which may contain or be changed by OH, NH, C-C, C-O, and C=O groups, were doped in the films. The films were mainly amorphous with a small amount of anatase and rutile phase.     

聚多巴胺对氧化处理后钛合金表面沉积羟基磷灰石的影响

利用阳极氧化法和微弧氧化法分别对医用钛合金表面进行处理,再经聚多巴胺薄膜表面修饰后,利用仿生溶液矿化法制备羟基磷灰石生物活性涂层,并研究聚多巴胺对经不同氧化处理的医用钛合金生物诱导沉积能力的影响;采用场发射扫描电子显微镜、X射线光电子能谱仪和X射线衍射仪对经不同氧化处理及其生物诱导沉积羟基磷灰石涂层的表面形貌、元素组成和相结构进行表征分析.结果表明：阳极氧化和微弧氧化处理后的钛合金表面分别形成了纳米管和微米孔结构;再经聚多巴胺修饰后,可以显著提高羟基磷灰石涂层的生物诱导沉积能力,而且使得羟基磷灰石的排列致密、规则.     

AZ31仿生沉积羟基磷灰石涂层的研究

采用镁合金AZ31作为研究对象,成功利用仿生法分别在24,48 h内在AZ31表面形成一次、二次羟基磷灰石涂层,随时间增加,涂层厚度增加.利用X射线衍射和扫描电子显微镜对涂层进行表征并对形成涂层的试样进行耐蚀性实验研究.结果表明,二次涂层试样表面的HA涂层比一次涂层试样在基体表面分布均匀致密,二次涂层试样的降解速率比一次涂层试样明显降低,通过控制涂层形貌、厚度可在一定程度上控制基体镁合金AZ31的降解速率.