• International Journal of Industrial Entomology and Biomaterials
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• v.15 no.1
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• pp.79-82
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• 2007

Lac is the dermal secretion of lac insect, Kerria lacca Kerr., which is used to make expensive natural dye, burnish, coating materials, in cosmetics and jewelry industry. Though it is very perspective industry and available of host plants over the country especially in southern districts of Bangladesh, lac cultivation is confined within some northern districts of Bangladesh. Experiment was conducted to find out the possibility of lac cultivation in two southwestern districts of Bangladesh: Khulna and Satkhira compared to Chapainowabgonj, the key lac producing district in Bangladesh, during February-October, 2006. The bark thickness, bark weight of ber plant, ratio of harvested and inoculated lac sticks, harvested raw lac, and harvested processed lac were measured and compared. Statistically, similar performance of lac cultivation was found regarding all parameters in three districts. These results recommended that lac cultivation is possible at the south-western coastal part of Bangladesh.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.5
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• pp.72-79
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• 2003

Nalita wood (Trema orientalis), one of the fastest growing woods in the world, is characterized anatomical, morphological and chemical properties at annual growth ring level in order to investigate as papermaking raw material. The proportion of fibers and vessel was increased with an increase of growth ring (from pith to bark). The fiber length of Nalita was increased with increasing growth ring, and an average fiber length was about 817 um. The average basic density of Nalita was about 0.38 g/cc. The total lignin & holocellulose in Nalita were increased and ash & alcohol-benzene extract decreased from pith to bark. These values were about 23.5 - 24.4 ％, 78.1 - 80.1 ％, 1.04 - 0.92 ％ and 2.1 - 1.8 ％, respectively. The xylan was the predominant sugar in the hemicellulose of Nalita.

• Journal of Korean Society of Forest Science
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• v.89 no.2
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• pp.208-215
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• 2000

In order to improve 'Salso' method (conventional tapping method) which was very inefficient in the aspects of collection time and labor, this study was carried out to investigate the effect of the application date and the distance from treatment point in the lactree(Rhus verniciflua) treated with 10% CEPA and to decide the possibility of application of the technique in the field. Bark thickness was significantly increased to the part 40cm above and below the treatment point, but urushiol content was increased to the part 20cm above and 10cm below the zone treated with 10% CEPA. The urushiol content of the bark was highest at 5cm above the treated zone and decreased in the order of 10, 20, and 40cm. And the urushiol contents of the bark of the upper part were higher than that of the low part. The effects of CEPA on bark thickness were similar to urushiol contents. Urushiol production of lactree is highly dependent on climatic conditions and particularly on the precipitation, and duration of sunshine. Ten percent of CEPA-lanolin pastes which was treated on June 16 affected bark anatomy and urushiol contents, while the treatment on August 24 did not affect. In the Rhus verniciflua treated with 10% CEPA, the urushiol contents was initially increased from 7 days after treatment, continued for the 4 weeks, and then slight decrease occurred at 5 weeks after the treatment. We measured a total sap yield by Salso method in lactree treated with 10% CEPA. By applying 10% CEPA, the sap yield was increased 3-4 times compared to that of untreated trees in the first tapping. But the relative ratio was gradually decreased from the second tapping to sixth, and after seventh tapping, the untreated trees secreted more sap than the treated trees. We discussed about the causes.

• Current Optics and Photonics
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• v.7 no.5
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• pp.569-573
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• 2023

We utilized terahertz time-domain spectroscopy (THz-TDS) to measure the thickness and electrical properties of nickel-chromium (Ni-Cr) films. This technique not only aligns well with traditional methods, such as haze-meter and transmission-densitometer measurements, but it also reveals the electrical properties and thickness of films down to a few tens of nanometers. The complex conductivity of the Ni-Cr thin films was extracted using the Tinkham formula. The experimental values closely aligned with the Drude model, indicating the reliability of our Ni-Cr film's electrical and optical constants. The thickness of Ni-Cr was estimated using the complex conductivity. These findings emphasize the potential of THz-TDS in quality control of metallic nanofilms, pointing toward an efficient and nondestructive test (NDT) for such analyses.

• Journal of the Korean Wood Science and Technology
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• v.5 no.1
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• pp.3-8
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• 1977

A bark comprises about 10 to 20 percents of a typical log by volume, and is generally considered as an unwanted residue rather than a potentially valuable resource. As the world has been confronted with decreasing forest resources, natural resources pressure dictate that a bark should be a raw material instead of a waste. The utilization of the largely wasted bark of genus Quercus grown in Korea can be enhanced by learning its anatomical structure and properties. In this paper, bark characteristics of Quercus grown in Korea are described. In bark anatomy, general features such as color of rhytidome, exfoliating form, color of periderm, arrangement of periderm, and thickness of the inner and outer hark. etc., arc discussed. Studies on the microscopic structure include sieve tube, companion cell, parenchyma, pholem fiber, ray, periderm(phelloderm, phelloogen, phellem), sclereid, and crystal, etc. The results may be summarized as follows: 1. In general characteristics of rhytidomes, exfoliating is not easy and sclereids are distint to the naked eye. Inner bark is thicker than that of outer bark except in case of Q. variabilis. 2. It is not clear to distinguish between phelloderm and phellogen in Quercus bark. The phellem is developed conspicuously in Q. variabilis but that of Q. accutissima is composed of thinwalled phellem and thickwalled stone cell. 3. Quercus Bark has sieve tube, companion cell, phloem fiber and sclereid. Sclereids of Quercus bark are the most distinguished characteristics comparing with pinus and populus. The volume percent of sclereids are higher than that of fiber. 4. Rays are 1~3 seriate, and multiseriate ranging with from 15 to 20. 5. Parenchyma cell contains two types, polygonal and druses crystal.

• Journal of the Korean Wood Science and Technology
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• v.45 no.4
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• pp.463-470
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• 2017

The objectives of this study are to obtain the basic knowledge of anatomical characteristics and wood properties of thinning trees of young teak (Tectona grandis L.F.) for fulfill the timber demand in Indonesia. Nine thinning trees of 5-year-old teak clone trees were used for analyzing the cell morphology and air-dry density. Vessel diameters in pore and outer pore zones were 165 and $90{\mu}m$, respectively. Mean value of fiber diameter, cell wall thickness, and fiber length in outer pore zone were $14.6{\mu}m$, $2.07{\mu}m$, and 1.04 mm, respectively. In addition, mean value of air-dry density was $0.55g/cm^3$. The measurement and values of vessel diameter, fiber diameter, cell wall thickness, fiber length and air-dry density in the experimental had lower than those in the older teak. Therefore, it could be suggested that the wood from thinning young teaks was not appropriate as construction material, but it could be used for furniture which do not need high of strength properties. Furthermore, since the measurements values of anatomical characteristics were still increasing from pith to bark, it could be suggested that 5-year-old teak clones are still in a juvenile phase. Positively significant correlations were found between air-dry density and cell wall thickness, indicating that cell wall thickness is strongly correlated with wood density of teak.

• Korean Journal of Pharmacognosy
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• v.11 no.2
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• pp.95-103
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• 1980

In our country there are five species of Morus genus including Morus alba L.. Also their varieties and hybrids are distributed so much. In sucession of previous report we collected control and marketing specimens of Mori Cortex Radicis, comparative experiments were pharmacognostically carried out to identify the control specimen by the differences of external and internal morphology. It was difficult to identify marketing specimens by external morphology, because they are similar in spite of conparating with control specimen which the origin is definite. In internal morphology, medullary ray is developed near the cambium to primary bark in control specimen A(Morus alba series) and C(M. Lhou series), but less developed in B(M. bombycis series). The difference of these three series was observed. The thickness of cork layer is almost the same($7{\sim}12$ layers) in A and C series, but B is thin layer and sample E(that on the market) is generally more thick and has a stick cork cell. The kinds of starch, Ca-oxalate and latex, cell centents were same, but it was easy to identify them by the differences of their distribution. The bast fibre of D(wild specimen) and E were light lignified, latex tube of A and C series was richer distributed than others. These results show that the origin of Mori Cortex Radicis on the market can be appreciated in four groups of Korean Morus genus which are M. alba, M. bambycis, M. Lhou series and the others.

• Journal of the Korean Wood Science and Technology
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• v.25 no.2
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• pp.117-126
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• 1997

In fast grown softwood, there are very large changes in material properties going outward from the pith to bark such as anatomical, physical and mechanical characteristics. Some of variations in anatomical properties with annual ring were then examined from Pinus koraiensis, Larix leptolepis, and Chamaecyparis obtusa, which are major softwoods of plantation in Korea. The large variations of annual ring width during young age of tree tended to stabilize after 25year through the transitional period in 17~23year. The ring density was 1.5~2.4 in 1~10year period, and 3.5~6.3 in 30~35year period, in which juvenile and mature wood were certainly assumed to be formed, respectively. Variations of tracheid length showed functional relationships with annual rings as logarithm. Demarcation between juvenile wood and mature wood could be 16~19year, which was determined from increase rate of tracheid length of 0.2%. Cell wall thickness increased with increase of annual ring even though large variations were observed as well. Variations of cell wall thickness within species were pronounced in latewood than earlywood. The increase of cell wall thickness from juvenile wood to mature wood was predominant in Larix leptolepis as 2.0times, and least in Chamaecyparis obtusa as 1.1 times. Cell diameters showed trends of increase during young age of 1~15year, and consistent afterward. The variations of cell diameter between radial and tangential direction were greater in latewood, and most pronounced in Chamaecyparis obtusa.

• Journal of the Korean Wood Science and Technology
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• v.21 no.2
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• pp.73-80
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• 1993

Pinus koraiensis is one of the most important reforestation species which had widely been planted around the country. Therefore, there are great research needs on the fundamental properties of wood to extend the frequency of uses and adequate availabilities. Research results on the characteristics of anatomical wood properties and changes are summarized as follows: 1. At a horizontal direction of tree trunk, the tracheid length at outer wood gradually becomes shorter as it reaches to pith. The tracheid length having between 32 and 42 annual rings showed over 2.5 times longer than that of pith, and also its length increases from the bottom to the top of the stem. 2. The tracheid diameters in latewood showed a little fluctuations, and the shortest near to the pith in earlywood. The tracheid diameters in earlywood are more than 2 times those of latewood, and the differences between the mature and juvenile wood in earlywood are less than 10${\mu}m$. 3. The tracheid wall thickness in early wood showed a little fluctuations. On the contrary, tracheid wall thickness in latewood rapidly increases from the pith to the bark. The tracheid wall of mature wood showed 10 to 20% thicker than that of juvenile wood. 4. The fibril angle at the secondary walls of tracheid within an annual ring showed higher degree in earlywood than that of latewood. The highest tracheid fibril angle was observed at around the pith of both earlywood and latewood. Then, fibril angle slowly decreased toward outer wood, and was stabilized after 15 years. 5. Structural boundaries between mature and juvenile wood from Pinus koraiensis are divided by 13 to 19 annual ring and distance of 5 to 8cm from the pith.

• Journal of Forest and Environmental Science
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• v.11 no.1
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• pp.81-101
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• 1995

Random amplified polymorphic DNA (RAPD) technology, a recent approach in molecular genetics, is much usable to select the elite trees and to maximize the genetic gain in forest tree breeding program, providing a clue to determine the genetic marker-trait correlation. This review intorduces research on bark thickness and breeding strategy in Pinus elliottii, Pinus caribaea and their hybrid by Queensland Forest Service and ForBio Research Pty Ltd, University of Queensland, which employ RAPD technology. Genetic linkage map of $F_1$ hybrids includes 186 RAPD markers and 16 linkage groups (1641 cM long in total) and 6 quantitative trait loci are located putatively for bark thickness. Following recent research results and experiences in pine breeding programs, the forseeable stages in the application and development are proposed for marker assisted selectin; stage 1-determination of species specific markers for genes controlling traits of commercial interest, and stage 2-determination of marker-allele association for specific allelic variants within pure species. As pines inherit their megagametophytes from the seed parent and zygotic embryos from both male and female parents, the determination of marker-trait correlation is possible even in embryo stage, eventually making ways for the early selection of elite individuals.