从全国第一届电子显微镜学术交流会看电子显微术在生物学、医学方面的应用概况

电子显微术的应用已普及至生物学、医学的各个分支,在方法学方面,发展和改进了常规透射电子显微镜及扫描电子显微镜的样品制备技术。介绍了多种国产包埋介质材料,例如~#600、~#650、~#618等。发现将固定后的样品放置在50％乙醇0.2M磷酸缓冲液中过夜,对肝细胞中的糖原保存有良好的作用。这对临床诊断能否作出正确的判断有实用价值。在制备扫描电子显微镜样品时,为了克服喷覆金属所造成的缺陷,介绍了组织导电染色法,能获得与喷覆金属效果相同的、清晰的扫描电子显微图象。与会的电子显微镜工作者还对冰冻复型技术,生物大分子样品的制备技术,电子显微镜放射自显影技术、酶标记技术与灌流固定技术等感到极大的兴趣,介绍并讨论了各种方法的优缺点及其应用概况。     

机载雷达射频隐身的空域不确定性研究与设计

针对空域角度的机载雷达发射波束方向图和波束扫描,研究了飞机的射频隐身技术。首先,在有无源探测系统先验知识的情况下,根据方向图综合与波束形成的互易性,利用最小方差无失真响应波束形成技术在无源探测系统方向上形成零点,辐射极低的能量;当没有无源探测系统先验知识时,通过副瓣电平控制方法降低雷达发射波束的副瓣,使得无源探测系统截获到尽可能低的能量。然后,研究了机载雷达发射波束扫描捷变不确定性技术,提出了基于元胞自动机的发射波束伪随机捷变方法。最后,仿真结果表明文中的方法和理论能有效提高飞机的射频隐身性能。     

皮秒激光对医用钛合金植入物表面微加工及生物相容性的研究

钛合金具有优良的综合性能,作为医用金属植入材料广泛应用于临床医学,而在钛合金植入物表面进行微造型有助于提高钛合金的生物相容性。采用1064nm波长的皮秒激光在钛合金(Ti-6Al-4V)表面进行微造型实验,并验证微造型的生物相容性。设计正交实验,通过扫描电子显微镜、扫描探针显微镜和共聚焦显微镜分析了样件表面形貌,建立微造型几何尺寸与激光参数的关系,确立了最优工艺参数,完成钛合金微造型样件制备。进行了大鼠骨髓间充质干细胞培养和免疫荧光观察细胞骨架实验。实验表明,微造型对细胞生长起到促进和引导作用。     

亚微米光刻的线宽测量技术

很久以来，传统的光学显微技术一直是IC测量中的重要技术，但它正在被共焦扫描显微技术、相干探测显微技术和扫描电子显微技术等精度更高的技术所取代。本文重点对用于在线线宽测量的低压扫描电子显微镜进行了讨论。     

植入式生物医疗光电子器件与系统

植入式电子信息设备已成为生物科学研究及医疗临床应用不可缺少的工具。以植入式光电子器件与系统为主题,介绍了面向生物医疗的各种植入式无源器件和有源器件的材料制备、工艺集成和可植入化策略,分类介绍了植入式光电子器件的能量信息传输方式;并从生物医学的研究和应用入手,介绍了具有代表性的植入式光电子系统。较为全面地阐述了现有的方法和技术,并结合实际应用和生物相容等需求,分析总结了各种技术方案的特点及其未来的发展趋势和面临的挑战。     

生长温度和化学剂量比对MgZnO合金薄膜相结构的影响

利用等离子辅助分子束外延技术,在蓝宝石c-平面上外延生长了ZnO单晶薄膜.原位反射式高能电子衍射结果表明,在650℃时样品为平整的表面.但X射线衍射测量表明,在此温度下添加Mg源生长的MgxZn1-xO合金薄膜,随Mg量的增加很快经历了六角相-混合相-立方相的相结构转变,这与扫描电子显微照片的直观结果相对应.分析指出该结果是由生长温度和Ⅱ、Ⅵ族元素的化学剂量比共同决定的.     

LTCC无源器件的应用与发展

低温共烧陶瓷(LTCC)技术在无源器件的研制方面具有功能化、集成化等优势,它的问世给无源器件的研究带来了革命性的变化。目前,LTCC技术的突破已经推动无源集成技术进入了实用化和产业化阶段,新一代无源元件和相关的集成技术成为倍受关注的技术制高点。未来几年LTCC技术仍然且必将成为无源集成技术的发展方向,加快我国LTCC无源器件技术的发展,是军用电子元器件的重要技术发展方向之一。     

用红外检测方法确定半导体器件上的残余膜

大规模集成电路和超大规模集成电路结构的形态一般是用三种显微技术即光学显微术、扫描电子显微术和透射电子显微术测定的。但是,业已证明,有许多种表面异常现象用上述三种显微技术是难以检测的。例如,残余的氧化膜就难以用光学显微技术观察到。     

用图像处理技术计算薄膜厚度和表面粗糙度

应用数字图像技术处理薄膜的断面扫描电子显微照片,定量分析薄膜材料的厚度和表面粗糙度.根据薄膜的断面扫描电子显微照片的特征,用垂直投影法计算阈值,根据阈值对薄膜显微照片进行二值化处理,获取薄膜材料表面图像;再将二值化后的图像做垂直投影,确定薄膜表面区域,并根据该区域区间去除噪音.对已提取的薄膜表面细化,提取薄膜表面轮廓线;确定薄膜的平均表面并计算出表面的粗糙度.应用局部垂直投影法,确定薄膜与衬底之间的界面位置.根据薄膜的平均表面的位置和界面的位置,计算出薄膜的厚度.     

EPON关键技术及其展望

无源光网络接入技术由于其支持高带宽和长距离等特性,将成为解决最后一公里问题的最佳方案.文章对以太无源光网络(EPON)的ONU自动发现、ONU测距、动态带宽分配等关键技术进行了分析和研究,最后对其技术发展方向10G EPON以及WDM-PON进行了展望.     

生物医用钛合金的激光表面改性

生物医用钛及其合金是外科植入首选的替代材料，激光表面改性是改善钛合金表面磨损和腐蚀性能的有效方法。采用高功率连续波Nd:YAG激光在Ti6Al4V合金表面进行激光气体氮化改性，获得了均匀致密、无孔洞裂纹等缺陷的氮化物改性层，合金表面对人体有害元素Al、V含量明显降低。利用扫描电子显微镜(SEM)、显微硬度计、振动摩擦磨损实验机及恒电位仪对Ti6Al4V合金气体氮化改性层的组织、磨损及在模拟人体体液中的电化学腐蚀性能进行研究。实验结果表明，激光气体氮化改善了Ti6Al4V合金作为生物医学材料使用的表面性能，其抗磨损及腐蚀性能显著提高。     

Innovative Materials Science via Machine Learning

Nowadays, the research on materials science is rapidly entering a phase of data-driven age. Machine learning, one of the most powerful data-driven methods, have been being applied to materials discovery and performances prediction with undoubtedly tremendous application foreground. Herein, the challenges and current progress of machine learning are summarized in materials science, the design strategies are classified and highlighted, and possible perspectives are proposed for the future development. It is hoped this review can provide important scientific guidance for innovating materials science and technology via machine learning in the future.     

Immunomodulation‐Based Strategy for Improving Soft Tissue and Metal Implant Integration and Its Implications in the Development of Metal Soft Tissue Materials

The difficulties associated with metal implants and soft tissue integration have significantly affected the applications of metal implants in soft‐tissue‐related areas. Prompted by the close association between soft tissue integration and the immune response, an immunomodulation‐based strategy is proposed to manipulate the immune microenvironment and improve metal implant–soft tissue integration. Considering their vital roles in soft tissue responses to metal implants, macrophages are used and the cytokines fingerprints of M1 and M2 macrophage immune microenvironments are evaluated for their potential modulatory effects on metal implant–soft tissue integration. The modulatory effects of different immune microenvironments on model soft tissue cells (human gingival epithelium cells) cultured on model metal implants (titanium alloy disks) are then described, with the underlying possible mechanism FAK‐AKT‐mTOR signaling unveiled. As further proof of concept, IL‐4/PDA (polydopamine)‐coated titanium alloy implants, aiming at modulating M2 macrophage polarization, are prepared and found to improve the in vivo metal implant‐soft tissue integration. It is the authors' ambition that this immunomodulation‐based strategy will change the negative perception and encourage the active development of metal materials with favorable soft tissue integration properties, thus improving the success rates of perforating metal implants and broadening their application in soft‐tissue‐related areas.     

BioMEMS和人体植入式生物微系统

MEMS技术在医药科学技术的一个重要应用是植入人体内的生物微系统(BioMEMS)。该系统集微传感器、微驱动器、微流体系统、微光学系统及微机械元件于一体,用于体内器官的诊断、体内器官功能修复或替代,其治疗效果确切,已成为关系本世纪医学与人类健康进步的重要领域。本文介绍了近年来不同功能类别植入式BioMEMS的发展状况,说明了MEMS工艺、方法及材料在此领域的应用。     

鬼成像的成像质量探究

鬼成像又称为双光子成像,是一种新型物理学研究技术.使用该技术,可以在获取不到物体本体的情况下通过双向传感器成像,因而得名"鬼成像".近些年,随着科学技术的发展,鬼成像因其特殊的成像方式被学术界人士重点关注.鬼成像技术先进,潜在社会价值很高.尽管目前针对鬼成像的相关研究还未完全突破技术瓶颈进而应用于日常生活,但已有的研究...     

计算机科学与技术的现代化运用

计算机的出现使得人类的生产效率取得了巨大的提升,社会不断发展进步,而计算机科学与技术的应用也给人类的生活带来了翻天覆地的变化。想要抓住工业革命所带来的无限发展机遇,就要深入探讨计算机科学与技术的发展和应用。文章从计算机和计算机科学与技术的概念出发,探讨了计算机的发展历程、发展方向和计算机科学与技术的发展方向与应用领域,以期能够抓住时代发展的命脉,在计算机科学与技术上引领潮流。     

Engineering New Microvascular Networks On-Chip: Ingredients,Assembly, and Best Practices

Tissue engineered grafts show great potential as regenerative implants for diseased or injured tissues within the human body. However, these grafts suffer from poor nutrient perfusion and waste transport, thus decreasing their viability post-transplantation. Graft vascularization is therefore a major area of focus within tissue engineering because biologically relevant conduits for nutrient and oxygen perfusion can improve viability post-implantation. Many researchers used microphysiological systems as testing platforms for potential grafts owing to an ability to integrate vascular networks as well as biological characteristics such as fluid perfusion, 3D architecture, compartmentalization of tissue-specific materials, and biophysical and biochemical cues. Although many methods of vascularizing these systems exist, microvascular self-assembly has great potential for bench-to-clinic translation as it relies on naturally occurring physiological events. In this review, the past decade of literature is highlighted, and the most important and tunable components yielding a self-assembled vascular network on chip are critically discussed: endothelial cell source, tissue-specific supporting cells, biomaterial scaffolds, biochemical cues, and biophysical forces. This paper discusses the bioengineered systems of angiogenesis, vasculogenesis, and lymphangiogenesis and includes a brief overview of multicellular systems. It concludes with future avenues of research to guide the next generation of vascularized microfluidic models.     

Phase Change Materials for Life Science Applications

Phase change materials (PCMs) are a class of thermo-responsive materials that can be utilized to trigger a phase transition which gives them thermal energy storage capacity. Any material with a high heat of fusion is referred to as a PCM that is able to provide cutting-edge thermal storage. PCMs are commercially used in many applications like textile industry, coating, and cold storage typically for heat control. These intriguing substances have recently been rediscovered and employed in a broad range of life science applications, including biological, human body, biomedical, pharmaceutical, food, and agricultural applications. Benefiting from the changes in physicochemical properties during the phase transition makes PCMs also functional for barcoding, detection, and storage. Paraffin wax and polyethylene glycol are the most commonly studied PCMs due to their low toxicity, biocompatibility, high thermal stability, high latent enthalpy, relatively wide transition temperature range, and ease of chemical modification. Current challenges in employing PCMs for life science applications include biosafety and/or engineering difficulties. The focus of this review article is on the life science applications, evaluation, and safety aspects of PCMs. Herein, the advances and the potential of employing PCMs as a versatile platform for various types of life science applications are highlighted.     

计算机技术在图形图像处理中的应用及关键技术研究

随着计算机科学技术的发展,计算机图形学已经成为现代计算机应用科学的一们重要学科,在社会各个领域计算机图形图像处理技术得到了广泛的应用.本文对计算机图形学的发展以及研究内容进行描述,对图形图像系统组成和基本内容进行了研究,对计算机图形学中图形图像处理应用的关键技术进行了研究.     

基于ZigBee协议智能家居监测系统的设计

科技的进步改变着人们的生活,电子技术的发展使得越来越多的家电设备现实了自动化.单个家电的自动化结合局域网技术,将整个家居智能化成为研究人员新的研究方向和思路.设计了一套以ZigBee协议为软件基础,CC2530为硬件平台的智能家居监控系统,该系统能够在家居环境下,进行温度、湿度、光照、煤气、人体等数据的采集和汇总,并能通过RS232串口上传至PC机上进行图形化的显示.根据实际测试,该系统能够完成家庭中相关数据的监测工作.