Coincidence Doppler broadening spectroscopy in polyvinyl chloride after doping with Al2O3

Coincidence Doppler broadening of annihilation radiation (CDBAR) and Vickers hardness techniques were performed to study pure Al₂O₃, pure polyvinyl chloride (PVC), and doped PVC with different concentrations of Al₂O₃ (10–50%). The CDBAR ratio curves with respect to pure PVC were presented and reflect the momentum distribution of all the samples. The peak around 14.5 ×10^?3 m_oC in the CDBAR ratio curves suggests a large contribution of positron annihilation with the Al₂O₃. There is a linear correlation between the height of this peak and the Al₂O₃ concentration. The S‐ and W‐parameters were extracted from the CDBAR spectra and increase with increasing the Al₂O₃ concentration showing discontinuity at 30% of Al₂O₃ concentration on PVC. The present data confirmed that there is no positronium formation in pure Al₂O₃ as a result of smaller S‐parameter. The Vickers hardness increases with increasing the Al₂O₃ concentration in PVC showing a linear dependence with two different slopes depend on the Al₂O₃ concentration range. A correlation between the Vickers hardness (macroscopic data) and the W‐parameter (microscopic data) was observed. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

丙烯酸二甲氨基乙酯的合成

以丙烯酰氯与二甲氨基乙醇为原料 ,乙醚为溶剂 ,过量的二甲氨基乙醇为缚酸剂合成了丙烯酸二甲氨基乙酯。较佳实验条件为 :丙烯酰氯 /二甲氨基乙醇 /乙醚 (物质的量比 ) 1∶2 .0 5∶5 .6 ,反应温度 5℃ ,反应时间 4h ,w(吩噻嗪 ) 0 .5 0 %,产物为无色透明液体 ,相对密度 0 .943 1( 2 0℃ ) ,折光率为 1.435 2 ,收率大于 91%。     

三氯乙酰氯的合成与应用

综述了三氯乙酰氯的合成方法及其在农药、医药等领域中的应用。     

佛尔哈德法测定氯化除汞上清液中的氯量

控制pH4-6，用锌粉还原氯化除汞上清液中的汞（Ⅱ）离子，取置换后液加入过量的硝酸银标准溶液，以硫酸铁铵溶液作指示剂，用硫氰酸钾标准滴定溶液滴定来测定氯量。该方法的检出限：0．25mg／100mL，回收率：98％-101％。     

从氯化铅渣中回收铅铋的研究

本文以柿竹园有色金属矿粗铋火法精炼、气化除铅产出的铅渣为原料，在常压下采用氯化钠水溶液进行浸出处理，有效地分离了铅和铋，并将铅制成了化工产品黄丹及硫酸铅     

在高速气流粉碎作用下PVC的力化学降解及形态变化的研究

通过ＧＰＴ、ＦＴ－ＩＲ、ＳＥＭ和力学性能测试，研究了在高速气流作用下聚氯乙烯（ＰＶＣ）的力化学降解反应、颗粒形态和微晶结构变化及其对ＰＶＣ物理、力学性能的影响。实验结果表明，经过高速气流处理ＰＶＣ，分子量将有所降低，晶体结构发生变化，颗粒尺寸和表观密度降低，比表面积增大，加工性能和力学性能得到明显改善。     

Factors Affecting 1-Octen-3-ol in Mushrooms at Harvest and During Postharvest Storage

Harvesting experiments revealed that immature whole mushrooms with closed veils had higher 1-octen-3-0l levels than more mature whole mushrooms with open veils. The l-octen-3-01 content of the gills was higher in immature mushrooms with closed veils, gradually decreased with maturity as the veil opened, and finally increased after the gills were well exposed. Postharvest experiments demonstrated that storage temperature influenced the activity of lipoxygenase-hydroperoxide lyase, but no differences in 1-octen-3-01 content were observed. Enzyme activity as well as 1-octen-3-01 content decreased during storage. Addition of calcium chloride to irrigation water, employed to improve quality and shelf life of fresh mushrooms, increased the amount of l-octen-3-01 immediately after harvest.     

Pitting corrosion of Cr–Mn–N steel in sulphuric acid media

The resistance to pitting corrosion of austenitic stainless steel Cr18Mn12N has been studied in model solutions of sulphuric acid (0.5 m) containing chloride ions (0.5 m). The cyclic potentiodynamic method has been employed to investigate the effects of chloride ions and agitation rate on the pitting and repassivation potentials. Electron and optical microscopy, electron diffraction spectroscopy and atomic absorption spectrometry have been used to detect the surface sites for pit formation and the growth of pit nuclei. The results obtained with chromium–manganese–nitrogen steel have been compared with those of austenitic Cr18Ni9 stainless steel. A similarity in pit initiation is established, while steel composition exhibits no significant effect. Cr18Mn12N steel is less prone to repassivation as compared with Cr18Ni9 steel.