柠檬酸对负载型磷化镍催化剂加氢脱硫性能的影响

采用溶胶-凝胶法制备了TiO₂-Al₂O₃复合载体,以柠檬酸(CA)为络合剂采用浸渍法制备了Ni₂P负载的TiO₂-Al₂O₃复合载体催化剂,并用 X 射线衍射(XRD)、N₂吸附比表面积(BET)测定、热重-差热分析(TG-DTA)、程序升温氢还原(H₂-TPR)和透射电子显微镜(TEM)技术对催化剂的结构和性质进行了表征,考察了加入CA对Ni₂P/TiO₂-Al₂O₃催化剂二苯并噻吩(DBT)加氢脱硫(HDS)性能的影响。结果表明,适量的CA可以丰富催化剂的孔道,提高催化剂的比表面积,使催化剂具有更好的孔结构、更高的金属活性组分分散度和更均一的活性组分尺寸。CA的引入可以减弱金属与载体之间的相互作用,显著降低Ni和P前驱体的还原温度,促进Ni-P-O活性相前驱态的生成。在360℃、3.0 MPa、氢油比500(体积比)、液时体积空速2.0 h^-1的条件下,反应4 h时二苯并噻吩转化率达到99.5%。在48 h内二苯并噻吩转化率可稳定在95.0%左右。     

Determination of P/Al ratio in phosphorus-doped aluminium oxide thin films by XRF,RBS and FTIR

Phosphorus-doped aluminium oxide thin films were deposited in a flow-type ALE reactor from AlCl₃, H₂O and from either P₂O₅ or trimethyl-phosphate. Structural information of the films was obtained from Fourier transform infrared (FTIR) spectra. Rutherford backscattering spectroscopy (RBS) was used to quantitatively determine the composition of the films. The P/Al intensity ratios calculated from X-ray fluorescence (XRF) results were in a linear relation with the P/Al concentration ratios calculated from RBS results. For comparison, the intensity ratios of the phosphorus peak (P=O) at about 1250 cm^–1 and the aluminium peak (Al-O) at about 950 cm^–1 were determined from the IR absorption spectra. The calibration of FTIR peak intensities was done by plotting the intensity ratios of phosphorus and aluminium peaks against the P/Al concentration ratios measured by RBS. FTIR gave also a linear calibration curve with RBS but the method is less suitable for routine analysis of P/Al ratio than XRF.     

正交试验法优化柠檬酸法氧化铝生产工艺

采用正交试验设计法,以丝钠铝石的收率为指标,考察了碳酸氢钠用量、pH值、反应温度和反应时间等因素对柠檬酸法氧化铝生产工艺的影响。 在优选工艺条件下：NaHCO3与Al摩尔比为5,pH=11,反应温度为80 ℃,反应时间为3 h,柠檬酸铝至丝钠铝石的转化率从原有的65%提高至76%。     

Determination of operationally defined fractions of aluminium in reference materials and acid attacked environmental samples

The aim of the presented work is to evaluate the selectivity of the operationally defined procedures for the aluminium fractionation in the reference materials and the environmental samples affected by the mining activity. The combination of the sequential optimized BCR (European Commission Community Bureau of Reference) three-step, the single (H₂O, CaCl₂, Na₂S₂O₄, NH₄F, (NH₄)₂C₂O₄, HCl, NTA, EDTA, DTPA) and the solid phase chelating ion-exchange extraction procedures was performed for the aluminium fractionation in the samples. The amount of the reactive Al determined by the solid phase extraction on the chelating resin Iontosorb Salicyl is the most important operationally defined fraction of aluminium from the aspect of its negative effects on the environment. The available Al concentrations obtained from the different operationally defined fractionation methods were compared. The flame atomic absorption spectrometry was used for the aluminium quantification. The X-ray diffraction analyse of the samples was performed for the mineral composition determination.The precision, the repeatability and the accuracy for the all steps of the optimized BCR sequential extraction procedure were checked on six reference materials (SRM 2710, RSS SO-2, RSS SO-4, CRM SA-B, SRM RTH 912, CRM 025-050). The precision and the repeatability were very good with the R.S.D. values ≤11%. The fraction specific accuracy was excellent. The new indicative fractional Al values in the used reference materials are published.     

三氯化铝催化合成阳离子淀粉

以淀粉和三甲基环氧丙基氯化铵为原料,在三氯化铝催化作用下,制备了阳离子淀粉,最佳反应条件为:淀粉 50g,三甲基环氧丙基氯化铵 10g,三氯化铝 0. 74g, 50%乙醇 60mL,反应温度 50℃,反应时间 17h.     

铈纳米膜对LY12铝合金表面耐蚀性能的影响

铝合金表面在使用环境中发生的腐蚀破坏限制了它的应用。采用Sol-gel提拉法在LYl2铝合金表面制备的铈纳米膜具有无毒、无污染和明显的防腐作用。表面分析测试结果表明，膜的主要成分为铈的氧化物；用XRD测试结果估算出膜中铈的粒径为10nm。盐水浸渍法试验结果证明了成膜后LYl2铝合金表面的腐蚀速率明显降低；成膜后试样的Tafel曲线腐蚀电势正移；EIS分析结果表明铈纳米膜具有明显的电容特征，该膜阻碍了铝合金表面腐蚀反应的发生；初步提出了铈纳米膜改善LYl2铝合金腐蚀性能的机制。     

荧光性的二(邻苯二甲酸异丙酯酰氧基)-丙烯酰氧基铝及其聚合物的合成、表征与性质

合成了螯合物二(邻苯二甲酸异丙酯酰氧基)-丙烯酰氧基铝(DIAA);以DIAA为单体进行游离基聚合合成了聚合物PDIAA.用元素分析、VPO、MS、ICP、IR、~1H-NMR和~(27)Al-NMR对其结构进行了表征,主要研究了它们在空气中的水解稳定性、热稳定性及其在溶剂中的荧光性质.     

Ring opening reaction of furan with high regio- and diastereo-selectivity via controlled addition of isatin-derived diazoamides

Reaction of cyclic diazoamides with furan systems using rhodium(II) acetate as a catalyst afforded a variety of (3Z)-3-[(2E)-4-oxopent-2-en-1-ylidene]indol-2-ones in a regio- and diastereo-selective manner. The diastereoselectivity was based on the flow rate of cyclic diazoamides. The representative products were characterized by single-crystal X-ray analyses.     

Yb（OTf）3-catalyzed synthesis of pyrroles under solvent-free conditions

A Yb(OTf)_3-catalyzed approach for the synthesis of pyrroles under solvent-free conditions was achieved,which could afford the desired products with yields ranged from moderate to excellent.