条码质量检测方法

介绍传统条码质量检测和综合分析等方法,对各种检测方法的优缺点作了一定比较,并提出条码印制质量控制的基本方法。     

Dielectric properties of carbon black and carbonyl iron filled epoxy–silicone resin coating

The dielectric properties of epoxy–silicone resin coatings containing carbon black (CB) and carbonyl iron (CI) particles as a function of frequency (2–18 GHz) and the CB volume content (0.2–1%) have been investigated. The complex permittivity of the coatings increased with increasing CB content, which mainly attributed to the interfacial polarization at the CB/resin/CI particles interfaces. The complex permittivity also decreased rapidly with increasing frequency in the low frequency range while decreased slowly in the high frequency range. The changes of dielectric properties with frequency and the CB volume content were discussed using the power-law decay and the concept of interfacial polarization.     

掺杂有机闪烁激活剂玻璃的荧光光谱和光输出

通过把有机闪烁激活剂p-TP、p-QT和POPOP等掺入低熔融温度的无机玻璃中，对玻璃的发光性能进行了探索。研究表明，掺杂有机激活剂的闪烁玻璃光输出较低，其主要原因是：①玻璃中存在的气孔等缺陷严重降低了玻璃的透光率；②玻璃中有机激活剂的实际浓度较低。由于玻璃基体中重原子的影响，使得闪烁玻璃的发射峰向长波方向移动，POPOP已起不到波长转换剂的作用，本身仅作为激活剂而发光。     

Processing sodium tellurite melts in low gravity drop shaft: part I Melt evaporation and formation of solid particles from vapor

Glasses of Na₂O·8TeO₂ and Na₂O·4TeO₂ compositions adhered to a small platinum heating coil (2 to 3 mm ID, 5 to 6 mm long) were melted and evaporated in low gravity using the drop shaft at the Japan Microgravity Center (JAMIC). The gravity level attained during the 10 s free fall was in the order of 10^–3 g. The species evaporated from the melt in low gravity generally formed a spherical smoke cloud surrounding the melt, whose size depended on the melt temperature and also on the time the melt evaporated in low gravity. The shape of the cloud was found to depend on several other factors, namely, the uniformity of heating, amount of melt, and the presence of gas bubbles in the melt. The evaporating species formed nearly perfect spheres of pure TeO₂ whose diameter ranged from 0.05 to 20 m. The size of TeO₂ microspheres increased with increasing melt temperature and time in low gravity, and was 5 to 10 times larger than that of similar particles prepared at 1-g.     

提高氢氟酸法分析精度的探讨

用传统的氢氟酸溶渣称重法分析 Al_2O_3—SiO_2陶瓷材料中玻璃相含量时,由于试样中的莫来石在氢氟酸中有部分溶解而呈现出较大的分析误差。本文提出一种对传统的氢氟酸法进行修正的方法,可以消除由于莫来石溶解所导致的分析误差,显著提高分析精度。用玻璃相数量为已知的标准样品,对 X 射线衍射分析法、传统氢氟酸法和修正氢氟酸法的分析精度进行了比较,结果表明,修正氢氟酸法的分析精度明显高于 X 射线衍射分析法和传统氢氟酸法。文中以分析 Al_2O_3—SiO_2系陶瓷型壳中玻璃相的数量和成分为例,介绍了修正氢氟酸法的应用。     

Lantern-Inspired On-Skin Helical Interconnects for Epidermal Electronic Sensors

Epidermal electronics have been attracting considerable attention due to their various potential applications in human-computer interaction and health monitoring. However, because of the lack of a self-adhesive and stable interconnect method between epidermal electronic sensors and rigid circuit boards, there remain difficulties in detecting body signals accurately by epidermal electronic sensors in daily life. Here, a 3D helical on-skin interconnect is first introduced for epidermal electronics sensors. Inspired by the structure of the accordion lantern, the interconnect is composed of two electrospinning polyurethane (PU) fiber films and a helical metal fiber. The helical metal fiber acts as a stable conductor with stretchability, and the PU fiber film with polydimethylsiloxane provides a self-adhesive substrate. Mechanical simulations and tests prove that the proposed interconnect can laminate conformally and unobtrusively onto human skin with excellent electrical stability (less than 0.5% electrical resistance change upon 100% elongation). Furthermore, based on the proposed interconnect, an all-in-one sensor-interconnect design is presented, which endows the epidermal electronic systems with anti-motion interference capability. A gesture identification wristband system realized by a single all-in-one strain sensor is demonstrated. Besides, a wireless on-skin system that accurately monitors dynamic 12-lead electrocardiographic is successfully built using all-in-one electrodes.     

基于时隙的多重冗余流指纹模型

随着互联网的日益广泛应用,各种网络安全问题频频暴露,以“打补丁”形式为主的安全增强模式难以有效防范日益增长的安全风险,网络安全领域研究者认为未来互联网体系架构应当将安全作为一种基本属性,实现网络架构对安全的内生支持。为了支持内生安全的数据可信,在流水印/流指纹机制的研究基础之上,设计实现了一种基于时隙的多重冗余流指纹模型。该模型使用3个时隙间隔,通过对指定时隙内的数据包进行延迟等操作,可在相邻比特操作不产生冲突的情况下实现指纹嵌入,并且引入冗余编码来提高指纹健壮性,同时考虑到网络中抖动或攻击者的恶意扰乱等行为,将延迟干扰、垃圾数据包干扰以及丢包干扰对模型的影响进行了理论分析,结果表明在给定网络流中数据的包分布时,随着冗余位的增加,指纹模型的鲁棒性明显提高。为了减少时间和空间消耗,提高数据包操作的效率和精度,基于内核设计和实现流指纹原型系统,并对其效率和鲁棒性进行评估,实验表明该模型具有很高的鲁棒性。最后,展示了所提模型的应用场景,基于该流指纹功能模型,能有效检测中间人攻击,预防网络身份欺骗。     

液氨贮罐液位测量的误差分析及解决方案

本文通过一个具体的实例，详细分析了差压式液位测量系统的误差来源及其消除方法，提出了在DCS中充分利用现有仪表资源构建新型测量系统(软仪表)的基本思想。     

界面对纳米SiC/LAS陶瓷复合材料微波介电性能的影响

利用激光诱导法制各的纳米SiC和LAS玻璃粉米，采用热压法制各纳米SiC／LAS陶瓷复合材料，研究了纳米SiC／LAS陶瓷复合材料微波介电性能与纳米SiC含量、烧结温度以及碳界面层的关系。结果表明，在1080℃以下烧结温度对陶瓷致密度的影响较大而对陶瓷复介电常数的影响较小；但在1080℃以上烧结温度对烧结致密度的影响较小，而对陶瓷复介电常数的影响较大，复合材料复介电常数的实测值与计算值之间存在很大的差异。通过计算和分析认为，复合材料制各过程中纳米尺度的SiC促进了碳界面层形成，使得烧结温度对复合材料复介电常数有很大影响。     

氮化硅多孔陶瓷的制备及微波介电性能研究

通过添加成孔剂,采用反应烧结工艺制备出具有不同气孔率的氮化硅多孔陶瓷.采用阿基米德法、三点弯曲法测试了材料的密度、气孔率及抗弯强度.用XRD及扫描电镜对相组成和显微结构进行了研究,用谐振腔法测试了该氮化硅陶瓷在9360 MHz频率的微波介电特性.结果表明,随着试样中气孔率的增加,试样的介电常数下降;在Si粉中添加α-Si3N4粉后,虽能提高氮化率,改善组织结构,但外加Si3N4和基体生产的Si3N4存在活性差异,两者结合不紧密,使强度降低;加入α-Si3N4粉使晶相组成中Si2ON2的含量降低,能够改善试样的介电性能.