Preparation of solar selective absorbing CuO coating for medium temperature application

A new method of preparing CuO solar selective absorbing coating for medium temperature is presented. After pretreatment, brass was overlaid with CuO by chemical plating. The effects of reactant concentration, reaction temperature and reaction time on the absorptivity of CuO coating were investigated. The optimized condition of preparing CuO coating was obtained. The CuO coating was analyzed with X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). In order to prolong the period of use, the CuO coating was protected by TiO₂. The experiment shows that the TiO₂/CuO coating is more heat-resistant, acid-resistant, and wear resistant than CuO coating, without losing absorptivity markedly. The TiO₂ coating can reduce emissivity and protect the CuO coating. Translated from Journal of Tianjin University, 2006, 39(12): 1485–1489 [译自: 天津大学学报]     

火焰原子吸收光谱法测定高纯石英粉中痕量钙

系统地研究了用空气——乙炔火焰原子吸收光谱分析法测定高纯石英粉中钙的最佳条件，建立了14％的乙醇作为增感剂，在2％盐酸介质中，0．4％ LaCl3溶液作为释放剂，用塞曼火焰原子吸收法测定的可行性方案，探讨了共存元素对钙的干扰及其消除。方法操作简便快速，干扰少，方法相对标准偏差小于3％，适用于日常分析石英粉中的杂质。     

氧化还原反应式配平中可能差错的几种情况

本文通过许多实例，指出了氧化还原反应式配平中可能出现的得失电子数不等或电荷数未配平、得失电子关系不对及反应式中酸碱性介质有错误等几种差错，并归纳了在酸碱性水溶液中平衡介质的方法。     

关于“不受《容规》监察的受压容器”技术要求的讨论

本文首先分析了《容规》所监察的压力容器的介质范围和GB150等压力容器标准的适用介质,讨论了不同介质的“不受《容规》监察的受压容器”技术要求的处理办法,并列举了简单的设计实例。     

基于最佳竞争窗口的IEEE802.11DCF接入协议改进及性能分析

针对DCF协议的初始竞争窗口不能随着节点数变化选择其最佳值的不足,提出一个具有两级退避的接入协议(OCW-DCF),并用Markov模型分析了协议性能,确定其最佳竞争窗口值。仿真结果表明,OCW-DCF协议能有效减小信道接入延时,且采用基本接入模式的总体性能比RTS/CTS接入模式的好。     

淋球菌培养基、氧化酶试纸及奈瑟氏菌快速糖试验试剂盒的检定和应用

应用新研制的淋球菌培养基（WGC）与意大利GC（IGC）和MTM培养基对照进行淋球菌生长试验，其敏感性基本一致。用已知菌株对氧化酶试纸和奈瑟氏菌快速糖试验试剂盒进行检定，亦呈现正确反应。应用WGC与IGC培养基培养9o3例临床标本，培养物经革兰氏染色和氧化酶试纸作初步检定，IGC卜淋球菌阳性402例，WGC上同时田位400例，两者符合率为99．5％，WGC上400例中，有366例用快速糖试验作证实试验，确诊为淋球菌者有364例，两者符合率为99．45％。     

绿色化学研究进展

对绿色化学在新型催化剂和反应介质方面的研究进展进行了综述。新型催化剂主要包括固体酸催化剂、固体碱催化剂、金属催化剂等。这些催化剂不仅具有较高的活性和选择性,而且催化剂和反应体系易于分离。新型反应介质主要包括超临界流体和离子液体,它不仅可以替代传统的有毒有害的挥发性有机溶剂,同时可以提高反应的活性和选择性,并且易于回收利用。高效催化剂和绿色反应介质的研究开发是未来绿色化学的重要研究内容。     

绿色盐水介质铜缓蚀剂的研究

以葡萄糖酸钙、钼酸钠、苯并三氮唑(BTA)、聚天冬氨酸、十二烷基葡萄糖苷、添加剂等合成了盐水介质铜缓蚀剂并用腐蚀失重法进行了评价.在22.5%盐水介质中,葡萄糖酸钙∶钼酸钠:苯并三氮唑∶聚天冬氨酸∶十二烷基葡萄糖苷=0.6∶1.0∶0.2∶0.3∶0.05,50℃时,铜缓蚀率可达98.5%以上.     

拱坝表孔泄流下游消能防冲形式的试验研究

摘 要：针对中型拱坝下游消能防冲形式的选择问题,通过物理模型试验,对比分析了长护坦防护、水垫塘+二道坝和短护坦先冲后护三种布置形式下相应的水力学指标。试验结果表明：长护坦方案时,水垫塘内水流流态较差,底板和护岸易失稳破坏;水垫塘+二道坝方案时,水流流态和各项水力学指标满足要求,但水垫塘和二道坝的造价较高;短护坦先冲后护方案时,冲坑位置及深度均在允许范围内,该方案的应用会受到拱坝下游地质条件的制约。依据短护坦先冲后护的试验成果,提出初步确定短护坦防护范围的方法。本工程下泄的单宽流量较小,根据试验成果及类似工程经验,并结合坝址地质和工程造价因素,推荐消能工布置方案为“短护坦先冲后护”方式。     

New synthesised pyridazine derivatives as effective inhibitors for the corrosion of pure iron in HCl medium

The inhibition of pure iron in 1 M HCl by new synthesised pyridazine compounds has been studied by weight loss, electrochemical polarisation and electrochemical impedance spectroscopy (EIS) measurements. The results obtained reveal that these compounds are efficient inhibitors. The inhibition efficiency increases with the increase of inhibitor concentration and reached 98% at 10⁻⁴ M for 5-benzyl-6-methyl pyridazine-3-thione. Potentiodynamic polarisation studies clearly reveal that the presence of pyridazines does not change the mechanism of hydrogen evolution and that they act essentially as cathodic inhibitors. The temperature effect on the corrosion behaviour of pure iron in 1 M HCl without and with the pyridazines at 10⁻⁴ M was studied in the temperature range from 298 to 353 K. EIS measurements show that the increase of the transfer resistance with the inhibitor concentration.