ASSESSMENT OF THE EFFECTIVE RANK OF A (CO)VARIANCE MATRIX: A NON-PARAMETRIC GOODNESS-OF-FIT TEST

Each eigenvector of the dispersion matrix[X]~T[X]was shown to be a partial predictor of the originaldata matrix [X],the sum of the predictions from the individual principal components being equal to theexpectance of [X].By comparing the distributions of the members of two neighbouring predictedmatrices,[X]_(1...i)and [X](1...i+1)(i.e.the sums of the first i and i+1 individual predictions respectively),it was shown that they should be indistinguishable provided that i is equal to or greater than the effectiverank of [X],and significantly different otherwise.This was confirmed by analysing the visible absorptionspectra of methyl orange and methyl red solutions as well as the Raman spectra of Na_2SO_4 and MgSO_4solutions.On the grounds of these findings,a non-parametric goodness-of-fit test for assessing theeffective rank of[X]was proposed which proved to be comparatively conservative and more robust thanmost currently used tests.     

新疆齐求Ⅰ金矿床毒砂及其在金的成矿过程中的作用

所研究的毒砂形成两个成矿阶段。成矿前阶段的毒砂具有颗粒粒大、裂隙发育和明显的成分环带等特征。成矿前的裂隙为金的迁移和沉淀提供了良好的空间。成矿期阶段的毒砂颗粒细小,无成分环带。根据形态、分布规律和成分特点,成矿期毒砂可划分为两个世代:早期的,自形程度高,无明显成分异常;晚期的,他形晶,含砷低。毒砂的特性反映了金的成矿作用的演变过程。     

氟碳钙铈矿的42R、48R的16H新多型

采用CM12透射电镜,对我国四川昌北M稀土矿床中的氟碳钙铈矿微结构特征作了电子衍射分析和晶格象观察,揭示出氟碳钙铈矿晶体中混合多型体的堆垛序列,在不同部分观测到不同的多型体,其中以氟碳钙铈矿6R多型为常见普通多型体。本次工作发现了42R、48R和16H三种新多型,并进一步证明,氟碳钙铈矿晶体中存在的多型结构相当复杂,但以长周期堆垛形成的多型体出现的几率要比短周期堆垛的多型体少得多。     

大别山高压变质杂岩中的硬玉

本文描述了在大别山高压变质杂岩中新近发现的石榴硬玉石英岩的岩石学物质特征。对高压指示性矿物硬玉的物理性质、光学性质、化学成分及结构进行了精确测定和研究。认为石榴硬玉石英岩与柯石英榴辉岩形成于同一高温超高压物理化学条件，硬玉的出现主要受控于原岩特定的化学成分。