A Study on Heat Transfer of Paulownia coreana and High-Density Fiberboard via Comparative Analysis

Kang, Seog-Goo,Lee, Sol-Ae,Son, Dong-Won,Kang, Chun-Won,Matsumura, Junji FACULTY OF AGRIC PUBLICATIONS-KYUSHU UNIV 2015 Journal of the Faculty of Agriculture, Kyushu Univ Vol. No.

녹차잎분말을 이용한 마루판의 유해 TVOC 제거효과

강석구 ( Seog Goo Kang ),이화형 ( Hwa Hyoung Lee ) 한국목재공학회 2008 목재공학 Vol.36 No.6

북미산 흑호두나무 Bi-Sn 용융합금 복합체의 제조와 특성

강석구(Seog Goo Kang),박계신(Kye-Shin Park),이호(Ho Lee),서인수(In Soo Seo),이종신(Jong Shin Lee),이화형(Hwa-hyoung Lee) 한국가구학회 2011 한국가구학회지 Vol.22 No.1

The metalized wood composites with natural grain of imported Juglans nigra, which was impregnated with low melting alloy were manufactured and evaluated in this study. And the proper manufacturing conditions was also investigated in this study. The low melting alloy with bismuth (Bi) and tin (Sn) which are harmless to humans, was applied to this new composites. The composites showed not only no defects of discoloration, delamination, swelling, and cracking, because of high dimensional stability and low thickness swelling, but also much improved performance such as high bending strength, high hardness, abrasion resistance, high thermal conductivity as floor materials. This study also suggested the proper impregnating condition, such as 10 minutes of the preliminary vacuum time, 186℃ of the heating temperature and 10 minutes of the maintaining pressure time at the pressure of 30 kgf/㎠. This metalized wood composites showed 7 times higher density than control, great increase in bending strength from 131.8 N/㎟ to 192.3 N/㎟, and great increase in hardness from 18.2 N/㎟ to 94.0 N/㎟. The composites demonstrated not only high emissivity of 91%, high shilding effectiveness of 92.59∼99.99%, high fire resistance but also great decrease in abrasion depth, water absorption and thickness swelling.

녹차잎분말을 사용한 마루판의 특성

강석구(Seog Goo Kang),이화형(Hwa Hyoung Lee) 한국가구학회 2010 한국가구학회지 Vol.21 No.4

This research was carried out to examine the properties of fancy cherry veneer overlaid on the PF resin bonded Meranti plywood floor, which 2.5% green tea leaf powder was applied in the UV varnishes and the adhesives for scavenging the volatile organic compounds. The results were as follows: 1. The various properties of the treated samples, such as density, moisture content, thickness swelling, bending strength(MOR), adhesion shear strength, surface abrasion, curling, cyclic delamination test with boiling water, boiling property, cold-resistance and heat resistance, acid resistance and alkali resistance, and anti-contamination property showed no significant difference between the properties of the control samples. 2.5% green tea leaf powder treated floor gave a little better results than the control for surface scratch test. 2. In case of QUV and weathering test, no difference between the treated sample and control was found. 3. The floor was discolored by adding 10% green tea leaf powder to UV coating, and the floor was also discolored to light green during by the soaking test. The color of floor was not changed up to 5% addition level.

硼素化合物 處理 파티클로 製造한 보드의 性質

강석구(Seog Goo Kang),이종신(Jong Shin Lee),이화형(Hwa Hyoung Lee) 한국가구학회 1993 한국가구학회지 Vol.4 No.2

The biological resistance and fire endurance are important to the particle board for interior and furniture materials. To obtain basic informations concerning those properties. we manufactured boards of treated particles with boron compound as wood preservatives and investigated effects of boron compounds on the mechanical and physical properties of particle board.<br/> The results were as follows ‘<br/> 1. The optimum borax treatment was approximately 0.1 % for oven dried weight of particles. Treatment wi th O. 1 % content of borax showed increased internal bond strength of 117% and increased bending strength of 76% ‘<br/> 2. When treated with borax and boric acid. bending strength of board showed about 25% increase at the mixture ratio of borax and boric acid of 3 to 7. However. the effects of bonding was poor than those of sole borax<br/> 3. The treatment of boron compound had not effects on dimensional stability of board. Addition of paraffin wax emulsion is necessary to manufacture of the board.<br/> 4. The treatment of boron compound can be expected for the manufacture of special particle board wih biological resistance. fire endurance and good bonding properties.

혈장변성접착제를 사용한 내수합판의 특성

강석구 ( Seog Goo Kang ),이화형 ( Hwa Hyoung Lee ) 한국목재공학회 2011 목재공학 Vol.39 No.1

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/mm2 of dry bonding strength, 0.80N/mm2 of wet boil bonding strength, 0% of cyclic delamination test value, and 0.025ppm of HCHO emission, which met the excellent super Eo grade and water resistant plywood.

왕대의 3방향에 따른 초음파적 특성

강석구 ( Seog Goo Kang ),이화형 ( Hwa Hyoung Lee ) 한국목재공학회 2011 목재공학 Vol.39 No.1

This research was carried out to examine the ultrasonic properties of Phyllostachys bambusoids Sieb et Zucc depending on three directions for providing the fundamental properties of the Korea traditional flute, Daekeum. The ultrasonic properties of Phyllostachys bambusoides Sieb. et Zucc were found to be different from those of wood, because of the distinctive anatomical structure of bamboo tissue. The ultrasonic velocity of peripheral zone showed higher values of all three directions. The ratio of longitudinal velocities to perpendicular velocities showed 116 at peripheral zone, 170 at central zone, 1.38 at inner zone respectively. The ratio of radial velocities to tangential velocities were measured as 1.286 at peripheral zone, 1325 at central zone, 0.829 at inner zone respectively.

Sound Absorption Rate and Sound Transmission Loss of Wood Bark Particle (목재수피 파티클의 흡음율과 음향투과손실)

( Chun-Won Kang ),( Eun-Suk Jang ),( Sang-Sik Jang ),( Ho-Yang Kang ),( Seog-Goo Kang ),( Se-Chang Oh ) 한국목재공학회 2019 목재공학 Vol.47 No.4

In this study, sound absorption capability and sound transmission loss of several kinds of target densities and thickness for six species of wood bark particle were estimated by the transfer function and transfer matrix methods. Resultantly, the mean sound absorption coefficient of a 100-mm thick Hinoki wood bark particle mat was 0.90 in the frequency range of 100-6400 Hz, whereas the mean sound absorption rate of a 50-mm thick Hinoki wood bark particle mat was 0.84 in the same frequency range. Particularly, at a thickness of 100 mm, it reached almost up to 100% in the frequency range of 1 KHz. The sound transmission losses of 100-mm thick Hinoki wood bark particle mat with a target density of 0.16 at 500 and 1000 Hz were 15.30 and 15.73 dB, respectively. When a 10-mm thick plywood was attached to the back of the wood particle mat, the sound transmission losses was increased by 20-30 dB. Wood bark can be used as an acoustical material owing to its high sound absorption rate and transmission loss.

분말상 탄닌수지를 이용한 파티클보드의 제조기술 및 물성개선

강석구,이화형 한국목재공학회 2004 목재공학 Vol.32 No.1

천연접착제인 분말상 탄닌수지를 사용한 파티클보드의 물리·기계적 성질의 개선을 위하여 분말상 탄닌수지와 액상 탄닌수지를 혼합하여 사용한 결과, 30:70 (분말 : 액상)의 혼합비가 최적조건이었으며 분말상 탄닌 수지의 비율이 높으면 물성이 저하되는 현상을 볼 수 있었으며 또한 포름알데히드 방산량이 E0 수준의 고내수성 제품을 제조할 수 있었다. 한편 요소수지 및 멜라민수지와 분말상 탄닌 수지와의 혼합방법은 물리·기계적 성질의 개선에 영향을 주지 못했으며, 유리포름알데히드 방산에 대한 scavenger의 역할만을 하였다. This study was carried out to improve the properties of powdered tannin adhesive(PT) by adding liquid tannin resin(LT) to PT in the manufacture of particleboard. Mixing the LT to PT from 50% to 100% by weight did not show any difference in particleboard properties, but the higher the powdered tannin resin ratio, the lower the properties of the board. The proper ratio of PT to LT was 30:70 for the improvement of PT-particleboard, unless LT lower than 70%. Internal bonding strength was in proportional to the amount of LT. Mixing amino adhesives and PT did not show any improvements in mechanical and physical properties of the board but they only acted as scavenger for the free formaldehyde. Manufacturing particle board with the adhesive of 30:70 (PT:LT) and by using double blender resulted in high-performance products of Eh level of formaldehyde emission with high water resistance (U type; below 12%, M type; below 25%), as well as saving chip drying energy.

Identification of occult tumors by whole-specimen mapping in solitary papillary thyroid carcinoma

Park, Seog Yun,Jung, Yuh-S,Ryu, Chang Hwan,Lee, Chang Yoon,Lee, You Jin,Lee, Eun Kyung,Kim, Seok-Ki,Kim, Tae Sung,Kim, Tae Hyun,Jang, Jeyun,Park, Daeyoon,Dong, Seung Myung,Kang, Jae-Goo,Lee, Jin Soo,R Society for Endocrinology 2015 Endocrine-related cancer Vol.22 No.4

<P>We undertook this study to estimate an accurate incidence and spread patterns of occult papillary thyroid carcinoma (PTC) in patients with a preoperative diagnosis of solitary PTC by using whole-specimen mapping of all specimens after a total thyroidectomy. Enrolled prospectively in this whole-thyroid mapping study are 82 consecutive patients who underwent a total thyroidectomy under a preoperative diagnosis of solitary PTC. All thyroidectomy specimens were serially sectioned in 2 mm thickness and whole-thyroid mapping was carried out for additional foci of occult PTC. The frequencies of occult lesions detected in the whole and contralateral lobe were determined, and clinicopathologic factors associated with multifocality were assessed. Whole-thyroid mapping revealed 66 occult PTC lesions missed by preoperative ultrasound in 37 (45.1%) of the 82 patients. The great majority (92.5%) of the occult PTC was smaller than 3 mm in size and 25 patients (30.5%) had contralateral lesions. We found that the male sex was an independent predictor of multifocality (odds ratio (OR), 3.00; 95% CI, 1.11–8.14), adjusting for preoperative findings. Analysis with pathologic parameters showed that the male sex (OR, 5.03; 95% CI, 1.68–15.08) and extrathyroidal extensions (OR, 3.03; 95% CI, 1.03–8.95) were associated with multifocal PTC. However, none of the clinicopathologic factors evaluated predicted contralateral PTC. Our study demonstrates the diagnostic limitations of ultrasound for the detection of multifocal PTC and the need to consider the possibility of occult lesions in the management of solitary PTC, especially in male patients.</P>