Author: Nikolai Bardarov
Articles
- IDENTIFICATION OF CERTAIN DIFFUSE POROUS TREE SPECIES ACCORDING TO QUANTITATIVE INDICATORS OF THEIR ANATOMICAL ELEMENTS
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Summary
In spite of the different diameter and density of the vessels of diffuse porous species, they can be more or less similar in these characteristics. This study discusses the differences of the vessels in several Bulgarian local growing tree species which have only single row core rays.
There are measured the average diameter and density of the vessels. Using them, the area of the individual anatomical components is calculated. The mean and the variance are determined in order to be used as diagnostic indicators. An examination of the statistical significance of the samples is made in order to determine which of the anatomical features can be used to identify the wooden species.
Keywords: diffuse porous wood species, poplar, populus, vessels, microscopy
- INFLUENCE OF SOME ANATOMICAL FEATURES ON THE DENSITY OF WOOD
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Summary
The wood of coniferous trees is characterized by simple and orderly structure. Within the annual ring the traheids are sealed and thickened. The work examines the relationships between anatomical characteristics of wood and its density.
The traheids have been examined in the wood of the spruce. Traces in the dimensional change in the annual ring have been measured successively from the earliest to the latest. The studied wood is divided into groups with narrow and wide rings. A comparison is made between the values for individual groups to seek relationships between anatomical structure and the density of wood.
Keywords: conifers, annual rings, traheids, spruce
- DETERMINATION OF TREE SPECIES IN QUANTITATIVE INDICATORS OF THEIR VASCULAR CELLS
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Summary
The wood of deciduous species are characterized by complex structure and greater specialization of cells. Besides the different diameter and density for each type trachea may be more or less similar in size. The work examines the differences of the trachea in several mestnorastyashti several tropical tree species.
Measured are the dimensions of cells and their variation within the annual ring. Certain cells are area variances and their diameter. Comparison is made between anatomical characteristics of individual species.
Keywords: wood, deciduous trees, tracheas
- EXAMINATION OF THE INFLUENCE OF RIBS ON THE ACOUSTIC PROPERTIES OF THE DECKS FOR GUITARS
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Summary
The quality of musical instruments depends not only on good wood, but the way of construction of oscillating parts. The work examines the impact of size and location of the ribs on the distribution of the resonance of the decks for guitars.
It was tested four decks for classical guitar. Consistently was measuring the acoustic characteristics of each of the boards building decks. It was followed the change of resonances after putting the ribs of the main schemes. It was established the influence of painting on the decks of the frequency and amplitude of the resonance.
Keywords: musical instruments, resonant wood, deck, ribs, resonances
- EXAMINATION ON THE MODIFICATION OF THE VESSELS WITHIN THE ANNUAL RING IN SEVERAL SPECIES OF THE GENUS OAK (G. QUERCUS)
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Summary
The construction of the ring porous wood species strongly depends on there width of the rings. It has most changing in the size and the location of the vessels. The work examines one of the main representatives of ring porous wood - genus Oak.
It was examined several species of the genus, and it was measured diameter and density of the vessels. It was examined the change of these anatomical features within the annual ring. Made a comparison between values to determine their impact on the use of wood.
Keywords: ring porouse wood, oak, tracheas, annual rings
- STUDY OF THE WOOD ACOUSTIC PROPERTIES OF THE USING A MODIFIED RESONANT METHOD
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Summary
Some of the unique properties of the wood are the acoustical. Together with its elastic properties they characterize this material to a great extent. Wood is unique with its characteristic of having high elasticity and damping of the low density.
This work examines the basic acoustic properties, as obtained by resonance method. Specimens of spruce wood, arranged in groups of varying density, are examined. The speed of sound, dynamic modulus of elasticity, acoustic constant and damping are set. Relations between the values of these properties in longitudinal and transverse oscillations are sought. The effect of density on the properties of the wood is established.
Keywords: wood, sound velocity, dynamic modulus of elasticity, acoustic constant