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• 2015-03-30 23:29發(fā)布了問答

  sem和tem中的電子探針的分析精度相同嗎？如果不同，請(qǐng)說出為什么

  　

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• 2013-12-25 22:14發(fā)布了問答

  什么是能譜分析儀

  　

  364人看過

• 2012-06-17 10:33發(fā)布了問答

  怎樣鑒別白銀質(zhì)量呢？

  有很多銀飾，有的越戴越亮，有的長(zhǎng)時(shí)間就暗淡了，買的價(jià)格差異也很大，白銀是不是貴的就是好的呢？

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• 2010-03-13 12:09發(fā)布了問答

  求助化學(xué)專業(yè)翻譯，謝謝

  Syntheses and properties of fluorinated phosphate acrylates used for UV-curing coatings The acrylated perfluoroalkyl phosphates (PFPA I and PFPA II) used as an oligomer and monomer， respectively， for UV-curing systems were synthesized... Syntheses and properties of fluorinated phosphate acrylates used for UV-curing coatings The acrylated perfluoroalkyl phosphates (PFPA I and PFPA II) used as an oligomer and monomer， respectively， for UV-curing systems were synthesized and characterized with 1H NMR and FTIR spectra. The photopolymerization behavior was investigated by using photo-DSC analysis， showing that both acrylates were photopolymerized quickly to a moderate final unsaturation conversion at the presence of a photoinitiator. The limiting oxygen indices of the UV-cured pure filmswere determined to be over 35. The surface properties of UV-cured polyurethane films added PFPAs， respectively， as additives were investigated by measuring the contact angles. The results showed that the addition of a small amount of PFPA I or PFPA II efficiently led to the increases in the contact angles， and the decreases in the surface tension. The X-ray photoelectron spectroscopy analysis confirmed that the film surface was enriched with fluorinated species. 展開

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