微电子火工品的发展及应用

微电子火工品在近年来得到了快速的发展,其中半导体桥火工品和电子延期雷管作为微电子火工品的典型代表,已经从军事应用走向民用.文章介绍了半导体桥火工品的结构、特点、作用原理以及发展趋势.同时介绍了半导体桥雷管、电子延期雷管、无线遥控雷管、先进的爆破网络等微电子火工技术在民用爆破领域的应用情况.     

半导体桥的设计分析

半导体桥是半导体桥火工品中最为关键的元件,它的结构和性质对火工品起着十分重要的作用,设计结构合理、性能优良的半导体桥是研究半导体桥火工品首要任务.文章以理论分析和文献分析为基础并结合试验数据,提供了一套半导体桥的设计方法,并选定了合理的结构和材料,给出了一组参数,确定了最小临界能的半导体桥图形.     

半导体桥升温方程研究

半导体桥火工品是取代桥丝的理想火工品。本文根据半导体桥的点火特性,应用电能转化为热能、热传导和炸药的热爆炸三个方面的理论,建立了在电容放电和直流输入两种方式下半导体桥桥体的升温特性方程;并通过计算机运算绘图,验证了方程基本符合理论要求。文章最后指出升温方程需加入修正系数来进一步完善。     

半导体桥升温方程研究

半导体桥火工品是取代桥丝的理想火工品。本文根据半导体桥的点火特性,应用电能转化为热能、热传导和炸药的热爆炸三个方面的理论,建立了在电容放电和直流输入两种方式下半导体桥桥体的升温特性方程;并通过计算机运算绘图,验证了方程基本符合理论要求。文章最后指出升温方程需加入修正系数来进一步完善。     

半导体桥火工品的防静电和防射频技术

对电火工品及半导体桥火工品防静电、防射频的常用方法进行了分析和概述,防静电方法主要是采用绝缘环或者泄放通道,防射频方法主要是采用屏蔽和低通滤波器。指出了现有常用技术存在的问题和今后的发展方向,认为现有方法无法完全泄放杂散静电、很难做到无缝隙屏蔽,或会增加火工品体积和质量。利用微电子保护电路,是半导体桥火工品静电和射频防护技术未来的发展方向。     

半导体桥火工品的发展

文中系统评价和分析了近年来国内外半导体桥结构，制造工艺和封装技术，展望了半导体桥点火装置及智能火工装置的应用前景。提示了这类火工品必将得到广泛应用的趋势。     

压敏电阻用于SCB火工品静电安全性研究?

为了提高半导体桥(SCB)火工品的静电安全性,利用贴片式压敏电阻优良的钳位电压能力对SCB火工品进行静电加固。恒流激励下发火试验结果显示,080C型压敏电阻对SCB火工品发火时间和爆发时间无显著影响;静电国军标条件下,SCB火工品均未发火,在静电美军标下全发火;080C型压敏电阻防护后,SCB火工品在美军标条件下均未发火,静电安全性得到了显著提高。因此,在不影响SCB火工品正常发火性能条件下,080C型压敏电阻能够显著提高SCB火工品的抗静电能力。     

半导体桥的研究进展与发展趋势

文章系统地综述了半导体桥芯片的研究现状和半导体桥点火性能测试的研究进展,并对半导体桥的发展趋势以及应用前景进行了分析和展望,指出今后应当对反应式半导体桥和其它新型半导体桥的设计、制备及点火机理进行研究。     

肖特基二极管防护后SCB静电安全性研究

为了提高半导体桥(SCB)火工品的静电安全性能,利用肖特基二极管(SBD)对SCB进行静电防护,对防护后的SCB火工品进行静电放电试验研究。研究结果表明:在静电放电条件（25 kV、500 pF、500 Ω）下,防护后的SCB火工品的桥区未烧蚀,电阻未发生明显变化,SCB未损伤。对静电试验后的SCB火工品进行电容发火试验研究,研究结果表明:静电试验后的SCB能够正常发火,SCB的爆发时间与发火能量未产生显著性变化,SCB的电爆性能未受到影响。     

基于桥丝式电火工品射频感度测试方法的探讨

本文介绍了基于桥丝式电火工品点火原理,提出并分析了基于桥丝式电火工品在射频干扰下进行射频感度测试的两种测试方法感生电流测试法、红外温度测试法.     

新型可调电压半导体桥起爆装置的研制与应用

由于SCB电雷管具有安全性好、可靠性高、抗电磁干扰能力强等特点,已经成为民用电雷管产品的发展趋势;同时由于SCB电雷管起爆的特殊性,设计一种专用SCB起爆装置已迫在眉睫。所研制的新型多功能SCB起爆装置具有体积小、工作电压低、反应速度快等优点,能够输出2~4kV的高压,能保证可靠起爆串联的50发SCB电雷管,并具有输出电压在线可调、显示等功能,是一款性能优越的多功能可变电压SCB起爆装置。本文阐述了该装置的组成、工作原理及关键技术设计,多次现场试验表明,其起爆性能优异。     

TVS二极管用于半导体桥静电安全性研究?

为了加强半导体桥(SCB)的静电安全性,利用TVS二极管抗浪涌特性,分别对经TVS二极管加固前、后的SCB进行静电安全性研究。研究结果发现:并联TVS二极管后,SCB的发火时间无显著性变化;在500 p F、不串电阻条件下,SCB在6 k V条件下均未发火,在8 k V条件下均发火;在500 p F、不串电阻条件下,TVS二极管加固后的SCB在9 k V条件下均未发火,在13 k V条件下均发火;9 k V静电作用后,TVS加固后SCB的发火时间无显著性变化。因此,TVS二极管既能不影响SCB的正常发火性能,又能有效提高SCB的静电安全性。     

Effect of mechanical activation pretreatment on the properties of sugarcane bagasse/poly(vinyl chloride) composites

This current work is concerned with the pretreatment of sugarcane bagasse (SCB) by mechanical activation (MA) using a self-designed stirring ball mill and surface modification of SCB using aluminate coupling agent (ACA). The untreated and differently treated SCBs were used to produce composites with poly(vinyl chloride) (PVC) as polymer matrix. The activation grade (A_g) measurement and Fourier transform infrared (FTIR) analysis of SCB showed that MA enhanced the condensation reaction between ACA and hydroxyl groups of the SCB fibres, which obviously increased the hydrophobicity of SCB. It was found that the mechanical properties of both the PVC composites reinforced by SCB with and without ACA modification increased with increasing milling time (t_M). Scanning electron microscopy (SEM) analysis showed that MA pretreatment significantly improved the dispersion of SCB in the composites and interfacial adhesion between SCB and PVC matrix, resulting in better mechanical properties of the composites.     

Dielectric study of the adhesion of mesenchymal stem cells from human umbilical cord on a sugarcane biopolymer

It is of current interest the identification of appropriate matrices for growing mesenchymal stem cells (MSC). These cells are able not only to regenerate themselves but also to differentiate into other type of functional cells, and so they have been extensively used in tissue engineering. In this work, we have evaluated the use of electric impedance spectroscopy (EIS) to follow the adhesion of MSC from Wharton’s jelly of the human umbilical cord (hWJMSC) on sugarcane biopolymers (SCB). Impedance spectra of the systems were obtained in the frequency range of 10²–10⁵ Hz. An EIS investigation showed that when deposited on a metallic electrode SCB films prevent the passage of electrons between the solution and the metallic interface. The impedance spectra of hWJMSCs adhered on SCB revealed that there is a significant increase in the magnitude of the impedance when compared to that of pure SCB. The corresponding resistance (real part of the impedance) was even higher for the SCB–hWJMSC system than for SCB without cells on their surface, in an indication of an increased blockage to the electron transfers. The resistance charge transfer is extracted by curve-fitting the impedance spectra to an equivalent circuit model. Also, a shift of the phase angle to higher frequencies was obtained for SCB–hWJMSC system as a result from hWJMSC adhesion. Our study demonstrates that EIS is an appropriate method to evaluate the adhesion of MSC. SCB can be considered as a promising biomaterial for tissue engineering.     

An insight into mode II fracture toughness testing using SCB specimen

The effect of friction forces between the test specimen and its bottom supports on the mode II fracture toughness values obtained using the semicircular bend (SCB) specimen is investigated. First, a number of experiments were conducted on SCB specimen in order to determine the mode II fracture toughness of polymethyl methacrylate (PMMA) according to the conventional approaches available in the literature. Three different types of supports that have been frequently employed by researchers in recent years were used to evaluate the effect of support type on the fracture loads. It was found that the friction forces between the supports and the SCB specimen have a significant effect on the value of mode II fracture toughness measured using the SCB samples. Then, the specimen was simulated using finite element method for more detailed investigation on the near crack tip stress field evolution when friction forces increase between the supports and the SCB specimen. The finite element results confirmed that the type of support affects not only the stress intensity factors K_I and K_II but also the T‐stress. The experimental and numerical results showed that the use of the crack tip parameters available in literature for frictionless contact between the supports and the SCB specimen can result in significant errors when the mode II experiments are performed by using the fixed or roller‐in‐grove types of supports.