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11.
Yanlin Huang Kiwan Jang Wanxue Zhao Eunjin Cho Ho Sueb Lee Xigang Wang Dake Qin Ying Zhang Chanfang Jiang Hyo Jin Seo 《Journal of solid state chemistry》2007,180(12):3325-3332
Usually, Sm2+ ions could be reduced by heating the materials in reducing atmospheres. Exposure to ionizing radiations is also known to cause Sm3+→Sm2+ conversion. In this work, BaBPO5 doped with the samarium ion was prepared by high temperature solid-state reaction. Sm2+ ions were obtained by two different reduction methods, i.e., heating in H2 reduced atmosphere and X-ray irradiation. The measurements of X-ray diffraction (XRD), and scanning electron microscope (SEM) were investigated. It is found that the conversion of Sm3+→Sm2+ is very efficient in BaBPO5 hosts after X-ray irradiation. Sm2+ ions under these two reduction methods exhibit different characteristics that were studied by measurements of luminescence and decay. The results showed that the luminescence properties of Sm2+ ions in BaBPO5 were highly dependent on the sample preparation conditions. 相似文献
12.
Shiori Hanada 《Tetrahedron letters》2006,47(35):6173-6177
Combination of commercially available platinum catalysts with siloxanes containing more than two Si-H groups is found to be an efficient catalyst system for the reduction of carboxamides to amines. In particular, facile removal of silicon and platinum residues from the product can be achieved by the use of polymethylhydrosiloxanes as reducing reagents. 相似文献
13.
活性炭酸处理对CuO/C催化剂上NO还原反应的影响 总被引:3,自引:0,他引:3
4种国产活性炭被用于NO还原反应,其中,山楂核炭和山桃核炭具有较高的NO还原转化率。实验发现,表面含氧基团-COO-对活性炭自身的还原性和对NO的还原活性有很重要的影响。对表面富-COO-基团的活性炭,稀盐酸处理使表面-COO-显著分解。 相似文献
14.
碲氢化钠是一个用途广泛的磁试剂,自作为有用的去溴试剂以来,日益受到化学工作者的关注,不断有文献报道它的合成及应用.例如能有效地还原卤代烃、硝基化合物、叠氮化合物和亚胺等.近年来,Katritzky报道了胺烷基化苯并三氮唑衍生物的合成及应用,此衍生物中的苯并三氮唑基是很好的离去基团,易被各种亲核试剂所取代.我们在前文中对硒氢化钠与胺烷基化苯并三氮唑反应生成二苄基二硒醚的合成进行了报道.本文用碲氢化钠与胺烷基化苯并三氮唑反应,结果生成还原产物N-取代胺. 相似文献
15.
以Mossbauer谱为手段,研究了用于F-T合成的Fe/Zn催化剂的物相结构,并考察了组成及制备方法的影响,同时还对其还原、碳化行为进行了探讨.发现锌对铁的还原有抑制作用,它能够稳定二价铁不被进一步还原.研究还表明,我们所研制的Fe/Zn催化剂是一种高分散度的铁锌化合物,室温下具有超顺磁特性. 相似文献
16.
使用TPR和H2-TPD技术对镍铝系催化剂的还原和氢脱附性能进行了研究,并与其催化性能相关联。结果发现,镍铝系催化剂的氢脱附能力与其催化性能之间有一定联系,脱附氢能力越强,催化剂的甲烷部分氧化反应性能就越好,但催化性能与还原性能无直接关联。 相似文献
17.
18.
《Electroanalysis》2005,17(20):1886-1894
Lamivudine (LAM) is a synthetic nucleoside analogue with activity against human immunodeficiency virus‐type 1 (HIV‐1) and Hepatitis B virus (HBV). The aim of this study was to determine LAM levels in serum and pharmaceutical formulations, by means of electrochemical methods using hanging mercury drop electrode (HMDE). On this electrode, LAM undergoes irreversible reduction at the peak potential near Ep?1.26 V (vs. Ag/AgCl/3 M KCl). Reduction LAM signals were measured by cyclic voltammetry (CV), differential pulse voltammetry (DPV) and square‐wave voltammetry (OSW). DPV and OSW techniques for the determination of LAM in acetate buffer at pH 4.5, which allows quantitation over the 4×10?6 to 1×10?4 M range in supporting electrolyte for both methods, were proposed. The linear response was obtained in acetate buffer in the ranges of 2×10?6 to 2×10?4 M for spiked serum samples at pH 4.5 for both techniques. The repeatability and reproducibility of the methods for all media were determined. The standard addition method was used in serum. Precision and accuracy were also checked in all media. No electroactive interferences from the endogenous substances were found in serum. With respect to side effects of high doses and short half‐life of LAM, a fast and simple detection method is described in this study. 相似文献
19.
Ingrid M. M. Fussing Derek Pletcher Richard J. Whitby 《Journal of organometallic chemistry》1994,470(1-2):109-117
The syntheses of several new CpTiCl2(OR) (R = alkyl, aryl) complexes are described. It was possible to isolate pure product when the R group is substituted such as to cause steric crowding at the metal centre; for example, particularly good yields of the phenolate complexes were obtained when there were isopropyl substituents in the 2 and 6 positions of the phenolate. Electrochemical studies of the complexes in dry THF show that the TiIII complexes are relatively stable, but only a diol complex could be reduced further to a TiII species. In general, the TiIV complexes undergo a reversible 1e− reduction reaction. The chemistry is more complex if the electrolyte contains added water: both the TiIV and TiIII complexes can react with water, the OR group being replaced by OH. The reaction is particularly rapid for the TiIII alkoxide complexes. 相似文献
20.