A high reactive penta-coordinated organic silicon compound(KSi(OCH 2CH 2O) 2(OCH 2CH 2OH)) was prepared, by the reaction of silica with ethylene glycol and potassium hydroxide, and di-hydroxy tetra coordinated silicon (OCH 2CH 2O)Si(OCH 2CH 2OH)(OCH 2CH 2OCH 2CH 2OH)(DHTS) was prepared by reacting penta-coordinated silicon complex with ClCH 2CH 2OH. Composite film of DHTS/polyvinyl butyral(PVB) was prepared by a sol-gel method. The thermal property, including glass-transition temperature of the composite film were examined. When the mass ratio of PVB to tetra coordinated silicon was 1∶1.7, the on set mass loss temperature of the composite film was increased by 27 ℃ in comparison with PVB. The transparency and tenacity of the composite film were all increased. But increase of the mass fraction of DHTS could decrease the decomposition temperature of the film.
对浙江天目山2株柳杉(Cryptomeria fortunei Hooibrenk ex Otto et Dietr,分别简称为CF-1,CF-3)及南京紫金山8株马尾松(Pinus massoniana Lamb.,分别简称为PM-1—PM-4,PM-7—PM-10)树轮δ13C平均值方位序列及2株柳杉树轮δ13C方位平均值年序列进行了谐波分析。分析结果及相关性检验表明,树轮δ13C值的方位变化有很强的谐波特征。第1次谐波与第2次谐波分量的方差贡献率占原序列总方差的百分比,除PM-8与PM-10低于70%外,其余均在70%以上,其中,CF-1与PM-9分别达到了93%和96.5%。第1次与第2次(或第3次)谐波的拟合序列与原序列的相关性极高,相关系数均在0.8以上,都通过了0.05的显著性检验,而且,两次谐波的拟合度均比较高,均在75%以上,拟合效果较好。分析结果表明,用2π与π(PM-1与PM-7为2π/3)两个主要谐波周期就可以较好地拟合各树轮δ13C序列的方位变化。初相位值的计算结果显示,第1、2次谐波的初相位值存在明显差异,这表明:不同树体2次谐波振幅的峰值出现的方位区域不同,即以2π及以π(PM-1与PM-7为2π/3)为周期的树轮δ13C方位变化的极大值并不出现在固定方位区。所以,两次谐波叠加的结果使树轮δ13C极值出现的方位区域更复杂。对天目山2株柳杉树轮δ13C各方位均值年序列的分析结果表明,2树轮δ13C极值均存在明显的年际漂移,其极大值出现频率较高的方位随树木生长坡向而发生转移。两树轮相比,多数年份其δ13C的主极大值出现的方位区基本发生45°的方位转移。而主、次极大值叠加的结果却使δ13C极值出现的方位基本发生90°的转移,这种极值转移的方向及转移度数与2株树所在坡向的变化和坡向变化度数正好相一致。
