工艺因素对纯钛表面磷酸锌转化的影响

利用化学转化技术在钛表面成功制备出均匀致密的化学转化膜。利用X射线衍射仪(XRD)、热场发射扫描电镜(FE-SEM)及电化学工作站对转化膜进行了表征。探讨了转化温度、促进剂类型及超声对转化膜的相组成、微观形貌及电化学性能的影响。在此基础上,选取75℃非超声的转化膜,对人成纤维细胞进行细胞培养,初步探讨了磷酸锌转化膜的生物相容性。结果表明:转化膜主要由磷酸锌组成;温度的提高有利于转化膜的形成;超声对转化膜的形核有促进作用,施加超声波后,即使在较低温度下也能形成完整的转化膜;合适的促进剂能够改变转化膜晶粒大小和致密程度。转化膜可以使细胞在其表面很好地进行粘附和铺展,表现出较好的生物相容性和生物活性。     

压制密度对块状NaOH在低温下溶解速度的影响

本文采用一种模具压制方法将细颗粒状NaOH制成不同密度的块状NaOH,测定其在水中的溶解速度。结果表明:压制的块状NaOH在水中的溶解速度随密度的增大呈现先增大后减小的趋势,溶解速度与密度成e指数相关性。     

井冈山之旅

正霞光渐远崇向晚,唤醒繁星布。暮色行,井冈山间,盘旋巨龙中。参差楼阁聚星灯,夜香弥漫,红色意情浓。前段时间,我和同事一起来到中国革命的红色摇篮——革命圣地井冈山,参加为期七天的业务培训。早就知道井冈山,但在印象中,对井冈山的感觉始终是书本上的页页历史,黄洋界炮声过后的战场,红军迂回行走的小路,淳朴憨直的革命老     

二氧化硅球的制备及其功能化

以正硅酸四乙酯为硅源,分别在碱性和酸性条件下制备了二氧化硅(SiO2)球状粒子;在碱性条件下制备了具有荧光功能的SiO2-FITC复合纳米球;以Sn2+作为敏化剂,在SiO2球表面沉积Ag纳米颗粒,制备了SiO2/Ag核-壳结构纳米粒子。通过透射电子显微镜(TEM)、紫外-可见近红外(UV-vis-NIR)分光光度计,荧光分光光度计对SiO2球,SiO2-FITC荧光纳米球,SiO2/Ag核-壳结构纳米粒子的形貌和光学吸收、荧光发射特性进行了表征。结果表明,碱性环境下制备的SiO2球粒径大小为纳米级,酸性环境下制备的SiO2球粒径大小为微米级,酸性环境下制备的SiO2球比碱性环境下制备的硅球致密。掺入FITC的SiO2球具有荧光发射特性,且发光强度可以控制。Ag纳米颗粒修饰的SiO2/Ag核-壳结构纳米粒子具有等表面等离子体共振吸收特性。     

步行系统规划的探索及实践

从步行规划的动机入手,论述了步行系统规划的切入点、难点、参考、衔接以及核心内容,并以上海市黄浦区步行系统规划为例,探讨了步行系统规划的开展需要注意的几个主要问题。     

数字货币交易匿名性与监管的博弈分析

By using technologies such as blockchain, digital currency, as a new type of monetary asset, has been promoting the development of digital economy. Digital currency trading platform plays an important role in the use of private digital currency by digital currency users. Existing digital currency trading platforms may expose users’ privacy and provide illegal elements with the conditions to participate in various abnormal trading behaviors such as “air dropping” events, extortion, fraud, etc. The strong anonymity protection of users by digital currency trading platforms also make it more difficult for regulatory authorities to supervise digital currency transactions. Therefore, the strength of the anonymity protection of users by digital currency trading platforms need to consider not only the privacy protection of users, but also meet the regulatory requirements. For this reason, based on the analysis of the relationship between the digital currency trading platforms and the supervisory departments, an evolutionary game model was established, the digital currency trading platform and the supervisory game model were defined and con-structed, and the replication dynamic equation was solved and the balanced solution was obtained according to the income matrix between the digital currency trading platform and the supervisory department. By building a Jacobian matrix, the stability of the evolutionary system under different parameters was analyzed. Besides, the evolutionary stable selection and strategy of the digital currency trading platform and the regulatory authority under different conditions were also analyzed. With Matlab, different strategies of anonymity protection of the digital currency trading platform and different strategies of supervision strategy of the regulatory department were simulated to veri-fy the accuracy of the game model. Based on the results of the simulations, some suggestions on the supervision of digital currency trading platforms are put forward, which provides a theoretical basis for the future supervision of digital currency trading platforms in China. © 2022, Beijing Xintong Media Co., Ltd.. All rights reserved.     

三导体横电磁波室的FDTD法分析

运用时域有限差分（FDTD）法模拟三导体横电磁波室（TTEM cell)内部的空间场分布；给出了在不同频率（30MHz、150MHz)正弦信号的激励下TTEM cell横截面的场分布和纵向场分布的理论值和实测值，理论计算与实测结果基本吻合，其结果对TTEM cell的工程设计具有重要的意义。     

钛及钛合金表面转化膜的应用及发展

对钛及钛合金的表面转化膜处理技术进行了综述,主要包括化学氧化、阳极氧化、硅烷化、磷酸盐转化等。阐述了各种处理方法的工艺过程及其作用效果,分别指出了各种方法的优缺点。同时展望了其今后的应用及发展前景。     

双能X射线安检图像中高原子序数物品的分割

研究了如何在尽量不受包裹特征的影响下将高原子序数的物品(如烟花爆竹、液体玻璃容器、手机、照相机、笔记本电脑、雨伞等)自动分割出来:首先是要能自动识别出包裹特征;然后是将已经识别出来的包裹特征区域进行剔除,以排除包裹特征对高原子序数物品分割的干扰;最后是利用高原子序数物品的材料性质将高原子序数物品从已经剔除了包裹特征的安检图像中分割出来。     

国外农田排水工程中的塑料排水暗管

近年来塑料排水暗管已在世界各国农田排水工程中大规模使用,逐步代替了陶瓦排水管。在西德,塑料排水暗管已占全部排水工程的65%;美国1975年生产的排水管中,60～70%为塑料管;荷兰1977年塑料排水管的生产已占总数的97%。