A statistical analysis of fibre size and shape distribution after compounding in composites reinforced by natural fibres

Phase-pure, highly crystalline sub-50 nm LiNbO3 nanocrystals were prepared from a non-aqueous solvothermal process for 72 h at 230 °C and a commercial precursor solution of mixed lithium niobium ethoxide in its parent alcohol. A systematic variation of the reaction medium composition with the addition of different amounts of co-solvent including butanol, 1,3-propanediol, 1,4-butanediol, and 1,5-pentanediol resulted in the formation of nanocrystals of adjustable mean size and shape anisotropy, as demonstrated from XRD measurements and TEM imaging. Colloidal stability of ethanol- and water-based suspensions was evaluated from dynamic light scattering (DLS)/zeta potential studies and correlated with FTIR data. Thanks to the evolution in the nanocrystal size and shape distribution we observed, as well as to the available literature on the alkoxide chemistry, the reaction pathways and growth mechanisms were finally discussed with a special attention on the monomer formation rate, leading to the nucleation step. The polar, non-perovskite crystalline structure of LiNbO3 was also evidenced to play a major role in the nanocrystal shape anisotropy.

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Air clathrate crystals from the GRIP deep ice core, Greenland: a number-, size- and shape-distribution study

Journal of Glaciology ◽

10.1017/s0022143000003002 ◽

1999 ◽

Vol 45 (149) ◽

pp. 22-30 ◽

Cited By ~ 32

Author(s):

F. Pauer ◽

S. Kipfstuhl ◽

W. F. Kuhs ◽

H. Shoji

Keyword(s):

Diffusion Processes ◽

Climatic Factors ◽

Ice Core ◽

Number Concentration ◽

Depth Range ◽

Shape Distribution ◽

Climatic Oscillations ◽

Size And Shape ◽

Distribution Study ◽

Core Project

AbstractWe performed microscopic observations and a statistical study of the number, size and shape distribution of clathrates in the GRIP (Greenland Ice Core Project) deep ice core, using 185 samples from a depth range of 1016–3014 m, spanning a period of 6 to >110 ka BP and encompassing the Holocene, Wisconsin and Eemian periods. The number concentration of the clathrates varied considerably with climatic changes. It was possible to detect the rapid climatic oscillations in the last glacial between 13 and 110 ka BP, the Dansgaard–Oeschger cycles, in the number-concentration profile of clathrates. The mean volume of clathrates is less clearly influenced by climatic factors, with a tendency towards greater volumes in warmer periods, but also a growth of clathrates with depth could be detected. This growth rate was calculated to be 3.1 × 10-12 cm3 a-1. The amount of gases captured in the clathrates is estimated to be significantly smaller than the total amount of air determined by gas-concentration measurements. This points to diffusion processes of atmospheric gases within the ice matrix.

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Advanced Statistical Analysis for Relationships between Particle Morphology (Size and Shape) and Shear (Static and Dynamic) Characteristics of Sands

International Journal of Geosciences ◽

10.4236/ijg.2013.410a004 ◽

2013 ◽

Vol 04 (10) ◽

pp. 27-36 ◽

Cited By ~ 2

Author(s):

Devapriya Chitral Wijeyesekera ◽

Alvin John Lim Meng Siang ◽

Ahmad Shukri Bin Yahaya

Keyword(s):

Statistical Analysis ◽

Dynamic Characteristics ◽

Particle Morphology ◽

Static And Dynamic Characteristics ◽

Size And Shape

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Some General Principles of Crop Rotation Experiments

Experimental Agriculture ◽

10.1017/s0014479700014265 ◽

1986 ◽

Vol 22 (2) ◽

pp. 187-198 ◽

Cited By ~ 11

Author(s):

D. A. Preece

Keyword(s):

Statistical Analysis ◽

Crop Rotation ◽

Design Principle ◽

Review Paper ◽

Good Practice ◽

Size And Shape ◽

Agricultural Experiment ◽

The Subject ◽

General Statistical

SUMMARYThis review paper deals with some of the general statistical principles of crop rotation experiments. The basic terminology of the subject is defined. Attention is paid to the fundamental design principle that each phase of a rotation should each year be present in an experiment involving that rotation. The inclusion of ‘auxiliary’ treatments - usually fertilizer treatments - is discussed. Consideration is given to matters influencing the choice of size and shape of plots. The statistician's role in planning a rotation experiment is portrayed as onerous. Emphasis is put on the importance of care and good practice in the management of a long-term agricultural experiment. Complications arising in the statistical analysis of data from a rotation trial are sketched.

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