双极数字/模拟电路的相容工艺探讨

实验研究了具有代表性的几种双极相容工艺,认为注磷调整法与现行双极工艺相容性好,在3种电路中应用获得成功,本文叙述了这一工艺方法和实验结果。

高可靠产品有铅和无铅混装工艺的质量控制

目前我国军工电子产品普遍存在有铅和无铅元器件混装焊接的现象，有铅和无铅混用时，可能会发生材料之间、工艺之间、设计之间不相容等问题，影响电子产品的可靠性。军工产品可靠性是第一位，既要保证焊点质量，又要保证不损坏元器件和印制板。本文通过对有铅和无铅混装焊接可能发生的不相容问题分析，对高可靠产品有铅和无铅混装工艺的质量控制方案提出一些建议。文章中的观点供参考并与同行共同讨论。

Application of polypropylene biofilm carrier modified by biocompatible, hydrophlic and magnetic additives to aerobic process

The designed new-type polypropylene biomass carrier/packing was modified by biocompatible, hydrophilic and magnetic additives and further charged with a permanent magnet （〈5.0×10^-3 Tesla）. The cartier was applied to biological contact-oxidation of synthesized wastewater. The results showed that the surface contact angle of modified carrier was reduced 22%, and the adsorbed water content increased by 300%-500%. The period of biofilm formation reduced from 7-9 days to 3-4 days after modification and magnetization. The hiodegradation process was reduced from 22.5 h to 10.5 h for completely removal of 500 mg/L CODcr by using the modified carrier. When operating in continuous mode, the modified carrier can reach a maximum CODa removal rate of 99% at the air-water ration of 40：1, while the original polypropylene packing may only achieve the maximum degradation efficiency of 79% at the gas-water ratio of 30：1.