使用单片机驱动微型针式打印头的一种新型设计方法

本文介绍了微型针式打印头EPSON M-192与单片机AT89C51的硬件接口的一种新型设计方法，同时给出了在此硬件设计基础上直接利用单片机驱动EPSON M-192的软件设计方法并重点阐述了如何装配打印字符点阵的软件算法。     

数字液压伺服控制纠偏系统

在生产、加工带材的机组中,由于带材的不平整、弯曲、厚度不均匀,机组的安装偏差,辊子间的不平行度等原因,都会导致带材的跑偏。本文详细介绍了带材纠偏系统的结构、原理及应用前景,分析了该系统控制器的实现过程,采用单片机对液压控制纠偏系统实现了数字量控制。     

The process modelling of epoxy dispensing for microchip encapsulation using fuzzy linear regression with fuzzy intervals

Epoxy dispensing is a popular way to perform microchip encapsulation for chip-on-board (COB) packages. However, the determination of the proper process parameters setting for a satisfactory encapsulation quality is difficult due to the complex behaviour of the encapsulant during the dispensing process and the inherent fuzziness of epoxy dispensing systems. Sometimes, the observed values from the process may be irregular. In conventional regression models, deviations between the observed values and the estimated values are supposed to have a probability distribution. However, when data is scattered, the obtained regression model has too wide of a possibility range. These deviations in processes such as epoxy dispensing can be regarded as system fuzziness that can be dealt with satisfactorily using a fuzzy regression method. In this paper, the fuzzy linear regression concept with fuzzy intervals and its application to the process modelling of epoxy dispensing for microchip encapsulation are described. Two fuzzy regression models, expressing the correlation between various process parameters and the two quality characteristics, respectively, were developed. Validation experiments were performed to demonstrate the effectiveness of the method for process modelling.     

Alkoxyresorufin O-dealkylase assay using a rat hepatocyte spheroid microarray

Hepatocyte multicellular aggregates (spheroids), which maintain high expression of liver functions, have been advocated as a useful culture technique for various cell-based assays. In this study, we investigated the drug metabolic function of a hepatocyte spheroid microarray (HSM) chip, which contained an array of 672 spheroids of primary rat hepatocytes within a 100-mm² region in the center of a poly(methylmethacrylate) plate (24 × 24 mm) and used an alkoxyresorufin (ethoxy-, methoxy-, pentoxy- and benzyloxyresorufin) O-dealkylase assay system. Ethoxyresorufin O-dealkylase (EROD) activity of the HSM chip initiated by 3-methylcholanthrene (3-MC), an inducer of cytochrome P450 enzymes, was 5- to 10-fold higher than that of monolayer hepatocytes, with activity being maintained for at least 2 weeks. We also demonstrated that 3-MC induced EROD, methoxyresorufin O-dealkylase (MROD) and benzyloxyresorufin O-dealkylase (BROD) activities in the HSM chip, while sodium phenobarbital (P450 inducer) induced pentoxyresorufin O-dealkylase (PROD), BROD, EROD and MROD activities. Induction of these activities was confirmed by increased gene expression of the related P450 enzymes. These results showed that the HSM chip had a good response to P450 inducers and that function was maintained for long periods of time. The HSM chip therefore may be a promising cellular platform for drug metabolic assays using hepatocytes.     

Synchronized current oscillations of formic acid electro-oxidation in a microchip-based dual-electrode flow cell

We investigate the oscillatory electro-oxidation of formic acid on platinum in a microchip-based dual-electrode cell with microfluidic flow control. The main dynamical features of current oscillations on single Pt electrode that had been observed in macro-cells are reproduced in the microfabricated electrochemical cell. In dual-electrode configuration nearly in-phase synchronized current oscillations occur when the reference/counter electrodes are placed far away from the micro-electrodes. The synchronization disappears with close reference/counter electrode placements. We show that the cause for synchronization is weak albeit important, bidirectional electrical coupling between the electrodes; therefore the unidirectional mass transfer interactions are negligible. The experimental design enables the investigation of the dynamical behavior in micro-electrode arrays with well-defined control of flow of the electrolyte in a manner where the size and spacing of the electrodes can be easily varied.     

红外遥控信号的一种编码解码方法

以HS0038(红外信号接收频率为38kHz)作为红外接收头，详细介绍了红外遥控信号的单片机软件编码解码方法，包括编码、调制和解码的原理以及以AT89C2051为核心的硬件电路和程序实现，实现了基于字节的红外数据传输。经实验测试，该方法能使红外遥控信号可靠发送和接收，传输距离可达15m，如果适当减少编码所用的脉冲个数，传输速度可达1200bit／s，该方法可用于一些计算机控制系统中。     

Wettability-patterned microchip for emerging biomedical materials and technologies

Microchip has long been studied and facilitated recent investigations in multiple biomedical and material fields. The advances in functional materials triggered several leaps in the development of microchip technology. Microarray chip, benefiting from micropatterning and nucleic acid nanotechnology, was firstly introduced around 1980 and rapidly facilitated genomics, proteomics, and biodetections. In the following generation, the microfluidic chips, raised from microelectromechanical systems (MEMS) and soft lithography, are revolutionizing several areas like biology, material fabrication, energy, and environmental science. More recently, the advances in materials fabrication keep expanding the frontiers of microchip platforms, like nanoscale fabrications and flexible device manufacturing. One of the most promising platforms is the wettability-patterned materials inspired by ubiquitous natural wetting creatures such as lotus leaf, spider silk, and Stenocara beetles. The unique property of handling liquids with no sophisticated equipment potentially facilitated the current microchip platform by combining the merits of microarray and microfluidics, and in turn, benefits material communities and beyond. In this featured article, we briefly introduce the state of art technologies to fabricate wettability-patterned chips and highlight some proof-of-concept demonstration of its emerging applications in material and biomedical science. We also give an outlook on its further developments including machine-learning micropattern manufacturing technology and reveal its potentiality to revolute several scientific areas.     

基于单片机的铁路机车信号发码器的设计

本文开发了一种新型的机车信号发码器,介绍了其工作原理和设计过程,包括硬件和软件部分,它基于DOS原理,利用C8051FD15单片机来实现其功能,并给出了技术指标。     

建立金黄色葡萄球菌肠毒素B悬浮芯片定量检测方法

目的建立金黄色葡萄球菌肠毒素B悬浮芯片定量检测方法。方法利用双抗体夹心法免疫学原理,以金黄色葡萄球菌肠毒素B的特异性抗体包覆微球为载体,利用悬浮芯片(Bio-Plex)系统建立检测模型;检测不同浓度金黄色葡萄球菌肠毒素B,测定方法的灵敏性;通过该方法对大肠杆菌、普通变型杆菌、蓖麻毒素和禽流感病毒HA、NH蛋白和金黄色葡萄球菌热休克毒素的检测,判断方法的特异性;将不同浓度金黄色葡萄球菌肠毒素B添加到奶粉中验证方法的实用性和稳定性。结果悬浮芯片方法对金黄色葡萄球菌肠毒素B的检测线性范围为0.2～1653.4ng/ml,最低检测值为203pg/ml,均优于酶联免疫吸附实验;除与2.3μg/ml金黄色葡萄球菌热休克毒素有交叉反应外,和其他几种细菌、毒素、蛋白均无交叉反应;对添加相同浓度金黄色葡萄球菌肠毒素B奶粉的检测的相对标准偏差在1.30%～16.93%。结论悬浮芯片定量检测方法对于模拟添加的金黄色葡萄球菌肠毒素B具有良好的检测效果。     

功能模块分离的无线传感器网络节点设计

不同ZigBee联盟成员开发应用层框架通常运行于各自指定的微处理器芯片上。由于各联盟成员的ZigBee技术细节不同,导致设计和使用及日常维护ZigBee网络时会发生兼容性问题。为此提出了一种将ZigBee节点上测控部分和通信部分分离为独立模块的思想,可以使ZigBee节点的开发和维护更加灵活和便捷。设计以Microchip的开源ZigBee协议栈和PIC18F4620单片机为实验平台,研究开发了测控和通信两模块间的控制协议,并完成了实际测试试验。实验结果表明,功能模块分离式的设计能充分发挥测控部分的硬件资源优势,减少对协议栈单片机的资源占用,提高了网络节点的兼容性和日常维护和升级的便利性。