• Journal of the Korean Wood Science and Technology
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• v.15 no.1
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• pp.1-11
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• 1987

A kraft black liquor obtained from pulping of pine (Pinus densiflora Sieb et Zucc) was used for producing three kinds of adhesive such as black liquor-phenol formaldehyde resin, methyloeated kraft lignin-phenol formaldehyde resin, and lignin cake-phenol resin. In case of producing black liquor-phenol formaldehyde resin, about 60 percent of the phenolic resin could be replaced by black liquor. Also the optimal press condition appeared to be $160^{\circ}C$ for 7 min. (l5.77Kg/$cm^2$ in dry test, 8.54Kg/$cm^2$ in 4 hr. boil test). Phenol could be substituted up to 80-90 percent by methylolated kraft lignin. The suitable conditions of factors affecting bond quality were pH to 2.6, methanol as solvent and 0.2ml formaldehyde per 1g of the adhesives, respectively. The optimal press condition was $150^{\circ}C$ for 4 min. (188.54Kg/$cm^2$ in dry test, 10.08Kg/$cm^2$ in 4 hr. boil test). In preparing lignin cake-phenol resin, a suitable mixing ratio of phenol to powered kraft lignin was one to one by weight. The optimal press condition was $150^{\circ}C$ for 4 min.(18.46Kg/$cm^2$ in dry test, 12.31Kg/$cm^2$ in 4 hr. hoil test).

• Progress in Superconductivity and Cryogenics
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• v.17 no.4
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• pp.43-46
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• 2015

The heavy ion accelerator that will be built in Daejeon utilizes four types of superconducting cavities. Cryomodules holding the superconducting cavities in them supply thermal insulation for cavities operating in 4.3 K or 2.1 K. A Prototype of cryomodule which holds two HWR (Half Wave Resonator) cavities was fabricated and tested. Since the operating temperature of the HWR is 2.1 K, the superfluid helium was generated with warm vacuum pumping system. The cyromodule was successfully cooled down below lambda point temperature of helium and any detectable leak was not observed during the test. The static thermal load at 4.2 K was measured. The result and the experience for the cool-down below lambda point of helium are reported in this paper.

• Journal of Sericultural and Entomological Science
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• v.36 no.1
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• pp.37-43
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• 1994

The effects of some sodium phosphates as auxiliary agents were studied on the blockade of hardness for silk degumming. In this work, four kinds of sodium phosphates were tested and the results were obtained through masking effects of metallic ions, difference of pH value and boil-off ratio. The degumming of calcium ingredient was analyzed by means of atomic absorption spectrophotometer and degumming test of cocoon shell was performed in the presence of calcium ingredient and sodium phosphates added to soap solution. In the view of the effects of sodium phosphates on calcium hardness, tetrasodium pyrophosphate(TSPP) and sodium phosphate dibasic(SPD) masked calcium ions more than sodium phosphate monobasic(SPM) and sodium hexametaphosphate(SHP). SHP and TSPP have excellent abilities of masking ferrous ions. The pH values of TSPP solution is higher than others, but lower than soap solution. The pH values were differently measured one another among the sodium phosphates but the boil-off ratio was increased in case of sodium phosphate with high pH value.

• International Journal of Industrial Entomology and Biomaterials
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• v.3 no.2
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• pp.127-133
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• 2001

With an objective of evolving quantitatively and qualitatively superior bivoltine breeds/hybrids of silkworm Bombyx mori L. for tropical conditions, breeding work was initiated in Central Sericultural Research and Training Institute, Mysore during 1992 by utilizing two Japanese hybrids namely BNl8$\times$BCS25 and Shunrei$\times$Shogetsu along with Indian evolved breed, KA. The breed CSR12 which is characterized with sex-limited larval marking and white oval cocoons was evolved from the Japanese hybrid BNl8 ${\times}$ BCS25 by crossing with KA, while the breed CSR6 which is characterized with normal marking (marked larvae) and white dumbbell cocoons was extracted from the Japanese commercial hybrid Shunrei${\times}$Shogetsu through continuous inbreeding coupled with selection. After fixation, these breeds along with other newly evolved breeds were subjected to hybrid study under optimum environmental conditions in the laboratory for expression of full potential of the genotypes. These hybrids were evaluated by Multiple Trait Evaluation Index (Mano et al., 1993). The hybrid CSR12${\times}$CSR6 was selected based multiple trait evaluation index value. The hybrid CSR12$\times$CSR6 recorded survival of 96.0%, shell weight of 50.0 cg, shell ratio of 24.3%, raw silk percentage of 19.6, filament length of 1,216 m, boil off loss of 22.4% and renditta of 5.1. On the other hand, the control hybrid (KA ${\times}$ NB4D2) has recorded survival of 90.6%, shell weight of 42.1 cg, shell ratio of 20.4%, raw silk percentage of 15.9, filament length of 999 m, boil off loss of 24.8% and renditta of 6.3. The hybrid CSR12$\times$CSR6 was authorized during 1997 by Central Silk Board, Government of India for commercial exploitation during favourable months based on national level race authorization test.

• Journal of the Korean Wood Science and Technology
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• v.39 no.1
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• pp.21-27
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• 2011

This study was carried out to examine properties of water resistant plywood by using serum protein adhesive which is natural, environment-friendly and human-friendly. For the preparation of the serum protein adhesive, pig blood from slaughterhouse was centrifuged and serum was separated from corpuscles and concentrated to 30% by dry weight basis. This concentrated serum protein was modified with PF resin (50% NVC) with the ratio of 9 : 2.5. Plywood made by this modified serum protein gave 1.21 N/$mm^2$ of dry bonding strength, 0.80 N/$mm^2$ of wet boil bonding strength, 0% of cyclic delamination test value, and 0.025 ppm of HCHO emission, which met the excellent super $E_0$ grade and water resistant plywood.

• Journal of the Korean Wood Science and Technology
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• v.24 no.2
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• pp.42-45
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• 1996

A residue from the newsprint waste was investigated as a filler in adhesive for bonding southern pine plywood. The residue was prepared by drying the wet residue to 8% moisture content and grinding the dry material using a laboratory Wiley mitt with a 75-${\mu}m$(200-mesh) screen. The residue was compared to a commercial filler commonly used in structural plywood adhesives. A total of 48 three-ply panels. 12.7mm nominal thickness and 0.3 by 0.3 m in size, were fabricated at two press times(4 and 5 min) and three assembly times(20, 40 and 60 min). Evaluations of the residue were carried out by performance tension shear tests after two 4-hour boil accelerated aging tests on plywood. The test results included tension shear strength and estimated wood failure values. All plywood made with the residue filler were comparable to the control-bonded plywood. These results indicate that residue from the newsprint waste streams would be suitable as filler for plywood adhesives.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.15-18
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• 2001

SMES consists of superconducting magnet, power converter and cryostat and HTS current lead. The prototype cryostat with HTS current leads and refrigerators was designed and manufactured for micro-SMES. HTS current lead with cryocooler was measured the temperature rise under dc current. The cryostat was evaluated the helium boil-off and mechanical stress during transfer and vibration test. These results will be applied to develope the micro-SMES system.

• International Journal of Naval Architecture and Ocean Engineering
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• v.10 no.4
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• pp.458-467
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• 2018

Efforts have been made in this paper to develop the measuring device for the insulation performance of full scale NO96 LNG CCS. The facility was designed to maintain environmental conditions which are similar to operation conditions of full scale LNG CCS. In the facility, the heat sink boundary was kept cryogenic temperature by cold chamber which contains liquefied nitrogen and heat source boundary was made by external case heated by natural convection. Heat Flow Meter method (HFM) was applied to this facility, hence Heat Flux Sensors (HFS) were attached to specimen. The equivalent thermal conductivity of full scale NO96 unit box was targeted to measure and PUF of same size was used for the calibration test. Additionally, the finite element analysis was carried out to check the performance of the developed test facility and experimental results were also compared with those predicted by the numerical method.

• Journal of the Korean Wood Science and Technology
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• v.26 no.1
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• pp.14-18
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• 1998

A low density polyethylene(LDPE) was examined as an additive in phenol-formaldehyde(PF) resin adhesive for bonding radiata pine plywood. The LDPE was supplied by the commercial manufacturer. The LDPE was compared to a commercial filler commonly used in structural plywood adhesives in the United States. The adhesive mixes were made by following the recommended procedure of Georgia-Pacific Resins Inc.. using plywood-type PF resin. A total of 48 three-ply plywoods. 6.3 mm nominal thickness and 30 by 30 em in size, were made at two press times (4 and 5 min). two press temperatures (150 and $160^{\circ}C$) and 30 minute assembly times for four adhesive mixing types. Evaluations of the LDPE addition were carried out by performance tension shear tests after two cycle boil aging tests on plywood per the U.S. Product Standard PS I-83. After accelerated-aging tests. plywoods were exhibited no delamination. The test results included tension shear strength and estimated wood failure values. The plywood test results support the use of polyethylene as an additive in plywood adhesives.

• Journal of the Korean Wood Science and Technology
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• v.25 no.3
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• pp.16-23
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• 1997

This study was carried out to discuss feasibility of high density polyethylene(HDPE) as a new substitute for the conventional adhesives in plywood manufacture. Plywood was composed of radiata pine(Pinus radiata) and Malas(Homallium feotidium) veneers and bonded by HDPE. Adhesion characteristics and anatomical scanning has been examined through tensile-shear strength test and scanning electron microscopy(SEM). The results are as follows; 1. Optimum loading quantity was 15g/$(30.3{\times}30.3)cm^2$, and tensile-shear strength increased with the increase of loading quantity. 2. Even at the hot pressing time of 1 minute, tensile-shear strength met the value of KS(over the 7.5kgf/$cm^2$), and tensile-shear strength increased with the increase of hot pressing time. 3. Plywood composed of veneer at moisture content of 19.6% showed similar tensile-shear strength to that at air conditioned moisture content of 11.4%. 4. Under the same condition of hot pressing time, tensile-shear strength of plywood bonded by HDPE met the KS value of boil and wet test and proved the same group as phenol formaldehyde adhesive. 5. HDPE films showed mechanical adhesion through penetration into the lathe check and ray of veneer.