新一代的国际互联网通信协议：IP Version6

本文通过对ＩＰｖ６和ＩＰｖ４协议的比较，讨论了新一代国际互联网通信协议ＩＰｖ６的特点，新增加的功能，并指出ＩＰｖ６协议的颁布对现有技术的影响和相应对策。     

Vital-Fluorochromization of Microorganisms Using 3′,6′-Diacetylfluorescein to Determine Damages of Cell Membranes and Loss of Metabolic Activity by Ozonation

Cell suspensions of Escherichia coli as a model for bacterial populations in wastewaters were treated with ozone as a disinfectant in a continuously operated pilot plant with a plug flow reactor. Suspensions with an initial number of CFU (colony forming units) of 10⁸ mL^?1 were ozonized with ozone concentrations up to 12 mg/L. Metabolic activities and membrane functions break down with increasing ozone concentrations. The fluorochromization using 3′,6′-diacetylfluorescein (FDA) proved to be a suitable method for the detection of an alteration in permeability of the cell membranes and an inactivation of metabolic activity. By fluorescence microscopic and photometric investigations it could be clearly demonstrated that, in the case of disinfection with ozone, inactivation of the cells includes first of all a damage of the cell membranes. In contrast to the determination of the number of CFU, fluorochromization allows the detection of alteration in metabolic activities.     

二苯并-18-冠-6的合成条件的优化

通过改变溶剂的极性、离子性、离去基团的活性及反应温度等方法,对传统的Pedersen冠醚合成法进行了优化,使目标产物的最高产率达到71%以上.产物通过IR、1H NMR及元素分析等方法进行结构表征.     

Ti-6-22-22S合金步进轧制工艺加工棒材研究

采用步进轧制工艺制备了Ti-6-22-22S合金Ф50mm棒材，对加工、热处理、组织与性能的关系进行了分析。结果表明：在两相区上部温度960℃轧制获得细网篮组织，棒材性能较好且数据均匀；热处理后，得到双态组织，强度．塑性达到优良组合，而片层状组织强度较高，但塑性稍低。     

基于SOCKS协议的IPv6/IPv4转换器

介绍了IPv6协议出现和IPv6和IPv4将长期共存的必然性。讨论了从IPv4到IPv6的各种过渡机制，包括IPv4网络中IPv6域间互联的机制及IPv6节点及IPv4节点间通信的机制。实现了一个IPv6／IPv4转换器，该转换器利用了SOCKS协议和6to4隧道方式。最后分析了这个转换器的适用性和特点。     

Na-MMT对MCPA6／PPO原位共混体系的影响

采用水辅助分散钠基蒙脱土（Na—MMT）通过原位共混的方法制备了浇铸尼龙6（MCPA6）和聚苯醚（PP0）共混物（95／5）。通过SEM、TEM和流变等考察了非常少量的Na-MMT对共混物形貌的影响。结果发现，PP0在MCPA6基体中尺寸从几十微米下降到一个微米左右，且所有的Na-MMT都分散在MCPA6基体中。DSC分析表明PPO分散相的尺寸影响了MCPA6的结晶行为。相比于纯的MCPA6，PPO和Na-MMT的协同作用提高了纳米复合材料的强度和韧性。     

IPv6 delay and loss performance evolution

Although packet delay and loss are two important parameters of the Internet performance, to the best of our knowledge, the evolution of large‐scale IPv6 delay and loss performance has previously not been studied. In this paper, we analyze more than 600 end‐to‐end IPv6 paths between about 26 testboxes of RIPE Network Coordination Centre over two years, and compare the delay and loss performance over time with their IPv4 counterparts. We present and discuss the measurement methodologies and show that IPv6 paths have a higher delay and loss than their IPv4 counterparts. The main reason for the worse performance stems from IPv6‐in‐IPv4 tunnels rather than from native IPv6 paths and such tunnels are still widely used today. Copyright © 2007 John Wiley & Sons, Ltd.     

Austenitizing treatment influence on the electrochemical corrosion behavior of 0.3C-14Cr-3Mo martensitic stainless steel

Effects of austenitizing treatment temperatures on aqueous corrosion properties of martensitic stainless steels were investigated by electrochemical tests (potentiodynamic test, potentiostatic test and electrochemical impedance spectroscopy), and surface analyses (optical microscopy and XRD). The results of potentiodynamic test revealed that the breakdown potential increased with the increased austenitizing temperature, indicating increased relative resistance to initiation of localized corrosion. EIS measurements showed that MSS3 (1030 °C) exhibits larger polarization resistance value than MSS1 (970 °C) and MSS2 (1000 °C) at passive and breakdown states. This was caused by decreasing the amount of Cr-rich M₂₃C₆ carbide which acts as preferential sites for pitting corrosion.     

兼容IPv4及IPv6的网络程序设计

介绍了在Window系统中设计兼容IPv4及IPv6的网络程序的方法,并给出了用WinsockAPI编程的具体步骤。