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纳米羟基磷灰石（纳米HAP）正在接受相当多的关注牙科用途，以及它们对釉质粘合剂是公认的。不过，也有关于HAP的其他牙科材料的影响未见报道，大部分在这一领域的研究是基于体外设计时，忽略唾液膜与磷灰石的相互作用。因此，这个原位试点研究的目的是评估的三个基于羟基磷灰石的解决方案与口服条件下，不同牙科材料表面的影响，它们之间的相互作用。因此，二志愿进行口腔内夹板与釉质和从三个牙科材料固定的样品：钛，陶瓷，和聚甲基丙烯酸甲酯（PMMA）。三HAP水样溶液（5％），用不同的形状和纳米HAP的尺寸（HAP I，II HAP，HAP III）制备。After 3 min of pellicle formation, 10 ml rinse was performed during 30 sec. Rinsing with water served as control. Samples were accessed immediately after rinsing, 30 min and 2 h after rinsing. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize the particles, and SEM evaluated the pellicle-HAP interactions. SEM and TEM results showed a high variation in the size range of the particles applied. A heterogeneous HAP layer was present after 2 h on enamel, titanium, ceramics, and PMMA surfaces under oral conditions. Bridge-like structures were visible between the nano-HAP and the pellicle formed on enamel, titanium, and PMMA surfaces. In conclusion, nano-HAP can adhere not only to enamel but also to artificial dental surfaces under oral conditions. The experiment showed that the acquired pellicle act as a bridge between the nano-HAP and the materials’ surface.

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目的. 研究了不同工艺制备的钴铬（Co-Cr）金属骨架在热老化后与单一低温瓷体系的结合强度。方法。使用传统的铸造，CAD / CAM制备了一百二十Co-Cr合金框架标本，和两个不同的商购激光烧结设备，和牙科瓷施加到标本。单一类型的牙科瓷（可乐丽则武牙科公司，东京，日本）的施加至试样。测定亚组后，将样品的一半进行的热老化过程。使用3点弯曲试验的试样的粘结强度进行了评价。使用立体显微镜的断裂试样的表面进行评价。从8组随机选择的样品的金属 - 陶瓷接合区已根据×1000放大倍数观察用SEM。使用由Kolmogorov-Smirnov检验检查所获得的数据的正常性分布。将所得到的本研究的数据进行统计分析用统计软件包程序（SPSS用于Windows 22.0，芝加哥，IL，USA）。结果。有CAD / CAM和其他三种方法，和CAD / CAM组的结合值之间的统计学显著差异的组中最高的。Besides, the bond strength between dental porcelain and 4 differently produced metal frameworks was high enough to surpass the acceptable threshold (>25 MPa) according to the ISO 9693. There was no statistically significant difference between thermal aging applied and nonapplied groups.结论。根据这项研究，它可以表明，金属陶瓷的粘结强度是取决于所使用的制造方法，但它不依赖于热老化应用的。It was found that the bond strength values of all samples with and without thermal aging application exceeded the minimum acceptable value of 25 MPa recommended by the ISO 9693.

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In this paper, the effect of Er addition (0.2, 0.5, 0.65, 0.8, 1.0, and 1.5 wt. %) on the microstructure evolution and tensile properties of as-cast hypereutectic Al-10Si-0.8Fe alloy was investigated. The phases and their morphologies in these alloys were identified by XRD and SEM equipped with EDX with the help of metallographic analysis techniques; the length of the secondary phase (LSP) and secondary dendrite arm spacing (SDAS) ofα-Al粮食定量。结果表明，第二相（初晶Si，共晶Si，和富铁相）和α-Al grain were significantly refined when the addition of Er increased from 0 to 0.8 wt. %. The mean LSP and SADS values were decreased to a minimum value when the Er addition reached 0.8 wt. %. However, the second phases andα-当Er含量超过0.8 wt.%时，Al晶粒变粗。XRD分析表明Er主要以Er的形式存在₂硅化合物。显微组织改性对合金的力学性能也有重要影响。屈服强度（YS）、极限抗拉强度（UTS）和延伸率（EL）分别从52.86 MPa、163.84 MPa和3.45%提高到71.01 MPa、163.84 MPa和5.65%。从断裂面上看，Er的弥散和钉扎强化是提高材料力学性能的主要原因₂硅相。

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Microstructural evolutions of EK61 superalloy during long-term aging until 1000 h at 700°C and 750°C, respectively, are studied by combination of Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM). Impact fracture morphologies after aging for different time are observed by the SEM. The microstructure is found to be relatively stable during aging at 700°C, and the fracture morphologies are characterized by transgranular fracture. At 750°C, the coarsening ofγ 相位超前凹痕的数量的减少，碳化物的在晶界导致晶间断裂的chainization，和的网η晶粒导致的层状裂解步骤在地层内相。显而易见的是，析出相的不稳定影响断口形貌显著。断裂形态和微结构之间的关系促进EK61超合金的服务可靠性的评估。

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乳腺癌可以通过早期诊断治愈。正确的病理诊断有助于临床合理有效的治疗。然而，由于缺乏有效的筛查和影像诊断方法，乳腺癌的早期常发展为恶性乳腺癌。本研究采用双光子激发荧光多光子显微镜（MPM）结合二次谐波技术对乳腺导管癌早期进行鉴别诊断。结果显示，正常乳腺组织、不典型导管增生、低级别导管原位癌和高级别导管原位癌微侵袭的细胞学特征和胶原分布存在差异。此外，从MPM图像中提取的三个特征被用来描述乳腺导管癌早期的细胞学特征、胶原密度和基底膜周长的差异。他们揭示了MPM具有无标记乳腺导管癌早期鉴别诊断的能力，这将有助于乳腺癌的早期诊断和治疗。本研究为MPM在临床上的进一步应用提供了基础。

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本研究提出一种有效且快速的扫描方法（例如电视扫描）与数位影像处理技术相结合，以取代传统的慢扫描模式，作为通用扫描电子显微镜（SEM）的标准采集模式。该方法获得的扫描电镜图像在锐度和噪声方面与慢扫描图像具有相同的质量，并且能够抑制在全真空条件下充电的不利影响，这是该领域一个具有挑战性的问题。在设计该方法时需要解决两个问题。一种是根据电视扫描图像的频率特性，利用逆滤波器对图像质量进行适当的补偿；另一种是设计一种精确的图像积分（噪声抑制）技术，其位置对准对噪声具有鲁棒性。这涉及到使用图像蒙太奇技术和估计需要集成的图像数量。最后将我们的电视扫描模式的结果与慢扫描图像以及传统的电视扫描图像进行了比较。

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