• Applied Chemistry for Engineering
• /
• v.24 no.4
• /
• pp.382-390
• /
• 2013

Foaming process of waste soda lime glasses by just chemical composition control of vitreous feed materials was investigated to find a novel and efficient recycling process. For the chemical composition control of feed materials, 10 wt. parts of $SiO_2$, 0.5 wt. parts of $Na_2SO_4$, 3.0 wt. parts of $B_2O_3$, and 0.3 wt. parts of carbon black as the foaming agent were mixed with 100 wt. parts of soda-lime vitreous feed powder. Proper conditions for foaming process in tunnel kiln are the foaming temperature of $830{\sim}850^{\circ}C$, the foaming time of 30~35 min, and the vitreous feed powder particle size of -325 mesh. Properties of foamed glass blocks obtained under these foaming conditions showed the density of $0.17{\sim}0.21g/cm^3$, thermal conductivity of $0.06{\pm}0.005kcal/h{\cdot}m{\cdot}^{\circ}C$, moisture absorption of 1.1~1.5%, and compressive strength of $20{\sim}30kgf/mm^2$.

• 대한치과보철학회:학술대회논문집
• /
• 2000.04a
• /
• pp.49-49
• /
• 2000

• Applied Chemistry for Engineering
• /
• v.16 no.4
• /
• pp.519-526
• /
• 2005

Hydrolysis of soda-lime waste glass was investigated to test the feasibility for use of waste glass as feed material in the production of foamed glass. The soda-lime glass, such as plate glass and various bottle glasses, was effectively hydrolyzed by steam and water under high pressure. The proper condition for the hydrolysis was found to be reaction temperature of $250^{\circ}C$ and reaction time of 2 h. Under this condition, the water content of hydrated glass through hydrolysis was 7.85~10.04%, allowing successful foaming process for production of foamed glass. Using Na as the modifying agent of glass was effective in the hydrolysis by water. The highest water content of hydrated glass was obtained when weight ratio of NaOH to the glass was 0.04.

• Journal of Mushroom
• /
• v.10 no.1
• /
• pp.15-20
• /
• 2012

Ventilation effects of bottles($1,100m{\ell}$) for culturing Flammulina velutipes on its mycelial growth and mushroom production were investigated. The degree of ventilation were controlled with hole positions, upper and under, and hole sizes in the bottle lids. The ventilation effects were measured with the contents of carbon dioxide, free sugars, chitin, moisture in the bottles and with the amount of produced mushrooms from the bottles. Carbon dioxide concentrations within the culturing bottles at exponential mycelial growth period vertex were relatively high in the bottles with lids without both a sponge and an aeration hole, and in those with a smaller hole. Free sugar contents in the mycelia were the highest in those with a 47mm hole on both sides, and in those with 26~33mm holes only underside. Chitin content was the highest in those with a 26mm hole only underside. On the other hand, the lids with 42mm~47mm holes on the both sides greatly lost water and decreased the mushroom production. In conclusion, the most efficient ventilation hole sizes on the lids for bottle($1,100m{\ell}$) cultivation of Flammulina velutipes using $1,100m{\ell}$ polypropylene bottle were 19mm on both sides of the lid and 26mm on only underside. They produced more mushrooms than the control by 6~9 %.

• Journal of Conservation Science
• /
• v.31 no.1
• /
• pp.21-27
• /
• 2015

The Phoenix-shaped Glass Ewer, which is No. 193 National Treasure, was seriously damaged by a unique form of green glass pieces when excavated among a number of burial accessories of Hwangnamdaechong known to have been formed in the 5th century. While it has long been exhibited at the National Museum of Korea since its treatment for conservation treatment at conservation science laboratory in 1984, the existing adhesive materials seriously deteriorated for the 30 years, and the condition was quite unstable. The epoxy resin used as a restorative materials turned yellowing due to the light and heat so much that it was no longer able to exhibit it in a stable and effective manner. As a result, a re-treatment for conservation was conducted lately. This study focuses on the three pieces of Gold wires used to carefully wrap up the handle of the Phoenix-shaped Glass Ewer broken into three pieces, which has not been studied so far. As for the analysis method for Gold wires, SEM-EDS and Stereo Microscope were used for nondestructive analysis. First of all, the result of the SEM-EDS analysis shows that the composition was Au 91.9 wt.%-Au 92.8 w.t% and Ag 5.9 wt.%-Ag 6.5 wt.%, which indicates that it was an alloy made of Au and Ag. The production technique of Gold wires was also observed by means of optical microscopes. In general, Gold wires were manufactured by a drawing process in which a lump of gold was beaten or pulled out of a hole or by a process of twisting a gold plate. However, Gold wires separated from the handle of the Phoenix-shaped Glass Ewer did not involve any trace of twisting on the surface. Rather, fine vertical stripes were observed with the sections filled up. Hence, it is thought that this Ewer went through a drawing process and then was mended. As a result, no certain relation with the golden mending material used for the Phoenix-shaped Glass Ewer was verified. The findings above indicate that most of the existing researches on Gold wires recognized them, not as separate remains, but merely as a component of other golden remains. Thus, there has been little systematic study on the manufacturing techniques of Gold wires. The future study on Gold wires may verify the correlation between the Gold wires used to fix the handle of the Phoenix-shaped Glass Ewer, which is examined in this study, with that of golden remains in the Silla era.

• Proceedings of the Korean Information Science Society Conference
• /
• 2010.06d
• /
• pp.408-411
• /
• 2010

본 논문에서는 의약품, 음료수병 등 액체용기에 부착이 가능하며, 주변 유전체에 의한 성능열화가 적고 소형으로 바코드를 대신하여 용기에 부착이 가능한 플렉시블 RFID 특수태그 안테나를 제안하였다. 제안된 태그 안테나는 PET 기판 위에 미앤더 기법으로 제작되어 제작 및 대량 생산에 용이하며, 범용 RFID의 사용주파수 (860~960MHz)를 만족시키고, 주변 유전물의 영향으로 인한 성능변화를 최소화할 수 있도록 설계하였다. 제안된 태그 안테나는 본체 중앙부에 T 정합회로를 사용하고 미앤더 구조와 직선 구조의 보조선로 2개를 본체 상단에 삽입하여, 캐패시티브 결합을 이용해 태그칩과의 임피던스 공액정합이 쉽게 이루어지도록 하였다. 또한 2개의 보조선로가 각각 다른 부착물체의 유전율에 상호 보완적으로 전류를 유기시 키도록 하여 주변 유전 물질의 영향에 의한 반사손실을 만족하도록 하였다. 본 태그의 성능은 송신출력 20dBm, 안테나 이득 6dBi인 리더 안테나를 사용하였을 때 자유공간에서는 3.5m, 유리 부착 시 2.61m, 액체가 든 유리병 부착 시 2.51m 의 인식거리 성능을 보였다.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
• /
• v.12 no.1
• /
• pp.63-73
• /
• 2006

The first packaging of Korean market milk dates back to July 1937 when Seoul Dairy Co-operative (Kyung Seong Dairy Co-operative in those days) used 1 hob (180 ml) glass bottles with either paper caps or cork caps. During 1945-1972, 2 hob (360 ml) glass bottles were produced, and iron caps and egret-shaped plastic film replaced the previously used caps. When there were insufficient numbers of milk bottles, other glass bottles such as soda drink bottles and beer bottles were used instead. Seoul Dairy Co-operative was the only dairy company existing in Korea until Nam Yang Dairy Co. Ltd was founded in March 1964, followed by Hae Tae Dairy Co. Ltd(Tae Han Food Public Corporation in those days) in 1969 and Mae-il Dairy Co. Ltd (Korea Dairy Company in those days) in May 1971. As many other dairy companies along with the above-mentioned companies were established, a variety of dairy products were packaged and marketed. In 1971 Seoul Dairy Co-operative first used triangular-shaped polyethylene film wrappers, and in 1972 Nam Yang Diary was the first company importing sterilized Tetra pak for the packaging of milk. Since 1974 rectangular shaped polyethylene film wrappers and plastic bottles were used. In 1977 the gable top carton pack made of paper was first introduced by Seo Joo Industry Co. Ltd, and its market share increased rapidly with gradual increase in its volume, from 180ml to 200ml, to 250ml, to 500ml and finally to 1,000ml, causing change in the volume of milk consumption. And in Sep. 1987 Pasteur market milk Co. Ltd. first used round type high density polyethylene bottle(body) with low density polyethylene cap of 245g, 490g and 980g volumes respectively.

• Science & Technology Policy
• /
• v.1 no.1 s.1
• /
• pp.13-13
• /
• 1991

노인성 알츠하이머 병의 원인 물질 발견 / 고려 인삼 중 Saponin 피부 노화 방지에 효용 입증 / 인공 합성 항암제 제조법 특허 / 마·일·유럽, IMS를 국제 공동 개발하기로 / HDTV용 디지털 VTR 세계 최고밀도 구현 / 창 유리를 TV안테나로

• Journal of Korean Ophthalmic Optics Society
• /
• v.16 no.1
• /
• pp.31-40
• /
• 2011

Purpose: This study was performed to investigate the actual state about ultrasonic cleaning of soft contact lenses in local optical shops and evaluate the removal effect of protein deposit on soft contact lenses with different lens containers by ultrasonic cleaner for eyeglasses. Methods: The actual state about ultrasonic cleaning of soft contact lenses was surveyed in total 75 local optical shops in Seoul, Korea. The cleaning efficacy of different lens containers was compared by measuring the protein remained on ocufilcon D contact lenses after washing by an ultrasonic cleaner for eyeglasses. The changes on surfaces and wetting angles of ocufilcon D contact lenses by repeat ultrasonication were further investigated. Results: The main purpose to use ultrasonic cleaners in local optical shops was rapid cleaning. The ultrasonic cleaning efficacy of ocufilcon D contact lenses with glass containers was little higher than it with plastic containers, but was not significantly different. The changes on surfaces and wetting angles of ocufilcon D contact lenses in a plastic lens container by repeat ultrasonication such as 30 and/or 60 times were shown. Conclusions: There was not significant difference in cleaning efficacy between glass and plastic lens containers. However, repeat cleaning with ultrasonic cleaner for eyeglasses would be carefully considered since some significant changes in the parameters of lens surface and wetting angles were detected by repeat ultrasonification even when lens containers were used for ocufilcon D contact lens during ultrasonictions.

• Proceedings of the Korean Society for Bio-Environment Control Conference
• /
• 1997.05a
• /
• pp.69-70
• /
• 1997

장미의 재배면적은 480㏊로서 국화 다음으로 많은 재배면적을 차지하고 있고 생산액에서는 130억원으로 전체 절화류 생산액의 28%를 차지하고 있다. 재배면적 480㏊중 457㏊(95.2%)가 시설재배이고 19.7㏊(41%)만이 루지재배로서 대부분이 시설내에서 재배되고 있다. 장미흰가루병은 B. C 300년경에 처음으로 보고된 이래 지금까지 장미에 가장 피해가 큰 병이다. (중략)