Liriodendron fossils have been widely found from the Cretaceous-Tertiary sedimentary rocks in Europe, North America and Asia. However, the relict species Liriodendron tulipifera L. and Liriodendron chinense (Hemsl.) Sarg. are endemic to North America and Southeast China, respectively. Their disjunct distribution is considered to be related to the continental drift occurred during the Tertiary. We document the morphological features and geographical distributions of the relict species to discuss the relationship between the ‘living fossil’ Liriodendron plants and continent drift of the Eurasia and North America.

抄録全体を表示

This study deals with thermogravimetry-differential thermal analysis (TG-DTA) and powder X-ray diffractometery (XRD) of the Sri Lankan-type vein graphite. The Sri Lankan-type vein graphite is well-known for its high purity with up to 95–98% of carbon content. It is thought that this vein-type graphite had been deposited from mantle-derived fluids. One of the largest vein-type graphite deposits of Sri Lanka occurs at Kahatagaha, in high-grade metamorphic rocks. Graphite crystals in these veins have grown mostly perpendicular to the wall rocks with at least four different textural types.
TG-DTA analysis is an effective tool for the distinction of graphitic material. This method can precisely measure simultaneously the difference in temperature between a sample and a standard and the rate of weight loss during combustion.
Basal spacing d (002) and width of d (002) spacing at half height of the peak for the four types of graphite crystals were measured by XRD. Crystal thickness along c-axis of crystallites in angstroms, denoted by Lc (002), was calculated using these graphitization parameters.
XRD results for the four types of graphite in a single vein show that the graphite crystals have identical fully-crystalline structure. However, TG-DTA data show variations in different peak temperatures and peak areas for the four different types of graphite crystals. We suspect that these variations are due to minor structural changes of graphite during progressive depositional process within a single vein.

抄録全体を表示

The OpenCurve published herein is an original computer software designed for morphometric analyses of biological forms that are represented by an open curve. It is based on Cartesian coordinate data digitized along the curve as functions of the cumulative chordal length of the curve. At the beginning of the procedure, collected coordinates are translated, rotated, scaled and reflected to obtain shape coordinates, and a series of x shape coordinates is subsequently detrended by subtracting their net linear change with the cumulative chordal length. A series of normalized data is used to calculate Fourier coefficients and discrete wavelet transforms that represent shape of the object of interest. The OpenCurve is also useful for illustrating synthetic shapes by use of inverse transform with a given number of harmonics. A supplementary program is also provided as an add-in macro of Microsoft Excel, which affords further analyses.

抄録全体を表示