汞在MnO_x-CeO_2/γ-Al_2O_3催化剂表面的赋存形态分析

为了高效经济地控制燃煤电站汞的排放,探索新型SCR催化剂上汞的催化氧化具有重要的学术价值和广阔的应用前景。Hg0在Mn Ox-Ce O2/γ-Al2O3(Mn Ce15)催化剂上被氧化后会以多种形态存在于催化剂表面,为确定Mn Ce15催化剂上汞的化合物的赋存形态,使用程序升温热分解方法研究了纯汞化合物的分解曲线,并与在不同烟气条件下处理过的Mn Ce15催化剂的分解脱附曲线进行了对比。研究确认了反应中Hg O、Hg Cl2、Hg(NO3)2和Hg SO4的生成,并根据实验结果分析了相应的汞化合物生成的反应路径。结果表明,在模拟烟气条件下Hg Cl2是主要的异相催化反应产物,同时可以在催化剂表面检测到少量Hg O和Hg SO4的生成。这一结论可为研究SCR催化剂上Hg0的催化氧化机理提供基础。     

捆绑式抗滑桩与钻孔灌注排桩算例效果比较

针对捆绑式抗滑桩中最简单适用的两根等直径钻孔桩的组合型式的捆绑桩,应用单棒与捆绑双棒承受侧向力作用下的对比实验成果,考虑设计计算理想状况的假定,采用了强度效能折减方法,以采用了钻孔灌注排桩进行边坡支护的实际工程为算例,对捆绑式抗滑桩结构设计计算进行了初步的探讨,并与钻孔灌注排桩方案的设计计算及效果进行了比较。结果表明由于捆绑式抗滑桩在抵抗弯矩上性能更优越,因此在受力钢筋用量上比钻孔灌注排桩大大节省,有更好的经济效果。     

Influence of air addition on surface modification of polyethylene terephthalate treated by an atmospheric pressure argon plasma brush

An atmospheric pressure argon plasma brush with air addition is employed to treat polyethylene terephthalate(PET) surface in order to improve its hydrophilicity. Results indicate that the plasma plume generated by the plasma brush presents periodically pulsed current despite a direct current voltage is applied. Voltage-current curve reveals that there is a transition from a Townsend discharge regime to a glow one during one discharge period. Optical emission spectrum indicates that more oxygen atoms are produced in the plume with increasing air content, which leads to the better hydrophilicity of PET surface after plasma treatment. Besides,an aging behavior is also observed. The hydrophilicity improvement is attributed to the production of oxygen functional groups, which increase in number with increasing air content.Moreover, some grain-like structures are observed on the treated PET surface, and its mean roughness increases with increasing air content. These results are of great importance for the hydrophilicity improvement of PET surface with a large scale.     

A multi-residue method for fast determination of pesticides in tea by ultra performance liquid chromatography–electrospray tandem mass spectrometry combined with modified QuEChERS sample preparation procedure

A multi-residue method was developed for rapid determination of pesticide residues in tea by ultra performance liquid chromatography–electrospray tandem mass spectrometry (UPLC/MS/MS). The QuEChERS method was used for sample preparation. In order to minimise the matrix effects from tea, a solid phase extraction (SPE) cartridge layered with graphite carbon/aminopropylsilanized silica gel was applied as complementary to QuEChERS method. For accurate quantification, representative matrix-matched calibration curves were applied to compensate matrix effects. Limits of quantification varied with different pesticides but all can be measured at 0.01 mg kg⁻¹ level in a 5 g tea sample except dichlorvos (0.02 mg kg⁻¹). Recoveries ranged from 70% to 120% and relative standard deviation (RSD) met the European United Quality Control guideline. Efficiency and reliability of this method were investigated by the analysis of both fermented and unfermented Chinese tea samples.     

采用新工质的单元式空调机参数化计算机辅助设计

介绍了采用新工质的单元式空调机参数化计算机辅助设计的方法、特点和内容、同时对采用新工质（R134a)和R22的单元式空气调节机的设计结果进行了分析比较，采用新工质的单元式空气调节机性能会达到或超过采用R11的单元式空气调节机。     

管道相关检漏系统的软件设计和实现

相关检漏系统的主机是一台便携式机,已经被广泛应用于工业水流管道及其他管道,但是价格昂贵、操作复杂.希望研制一套相关检漏软件,它可以安装在一台便携式通用微机上,替代主机,省去一批硬件,不但可以提高测试精度,也降低了系统的成本.     

具有规则变化孔洞蜂窝结构织物的织造工艺探讨

蜂窝材料以其质轻、抗冲击性能佳等优点广受好评,但通过黏合剂黏结而成的蜂窝材料一旦处于湿热环境中,分层处的性能衰减严重。采用纺织技术直接制备一种层与层之间纱线连续的三维织物,经打开后可一次整体形成蜂窝结构,并织造了4、6及8层蜂窝结构织物,为拓展蜂窝织物结构变化提供了有益参考。     

环保型稀土钨电极坯条制备技术研究

本文针对环保型稀土钨电极坯条高效低能耗制备技术进行研究,对钢模压制和等静压压制进行了对比试验,并对垂熔烧结和中频烧结进行了对比试验。结果表明：等静压压制坯条——中频烧结方式制备的坯条密度、组织更均匀,减少原材料消耗2.3%,并在后续加工过程中有效避免内部裂纹的产生。此法生产可实现批量操作,比单根操作效率明显提高,电能消耗降低70%以上,为环保型产品的规模推广应用提供了技术支撑。