Al 금속분말을 zircon sand (ZrSiO4)와 A12O3혼합체에 첨가하여 반응소결시킴으로써 무수축 Mullite-ZrO2, 요업체를 얻고자 하였다. 반응식, 3(Al+Al2O3)+2ZrSiO4→3A12O3 .2SiO2+2ZrO2에 의하여 ZrO2-강화 Mullite 요업체를 제조하였다. Al 분말은 A12O3에 대해 0-30 무게 퍼센트까지 대체하였다. 평량한 분말을 볼밀하여 혼합 분쇄한 후, 정수압 성형하여 시편을 제조하고, 온도범위 1450-1600˚C에서 3시간 반응소결시켰다. Al의 충분한 산화를 위해, 한편으로는 1250˚C에서 5시간동안 열처리를 거친후 소성온도로 올리기도 했다. Al을 첨가함으로서 반응은 촉진되었으며, 소성수축도 산화한 Al의 부피팽창에 의해 상쇄되어, 무수축요업체 제조의 가능성을 보였다. 박편모양을 한 비교적 큰 Al분말이 잘 분쇄되지 않음으로 해서, Al이 자리했던 곳에 큰 기공을 남겼다.
This study was conducted to examine the effects of additives and drying methods in Yukwa's manufacture. Additives had significant effects on hardness, and bean water and bean powder added group rated better than the baking powder and boiled bean added group. Sensory evaluation test showed that bean water and bean powder added group produced higher desirability. Drying methods had significant effects on all attribute of sensory evaluation, natural drying and incubative plate drying produced higher uniformity, denseness and overall desirability.
This research was conducted to obtain the basic information on the cell block phenomenon occuring during early development in vitro of mouse embryos. Early embryos were recovered at 3h post-hGG injection(hph). Various chemicals (EDTA, EGTA, DTPA, MA and PRA) were tested to examine the effects of them on the overcoming the 2-cell block phenomenon. One hundreds M of the chelating agents were added to the M16 medium containing embryos. The treated embryos were worked and transferd to fresh M16 medium after 1, 3, 6 and 12h of treatment. Development was examined at 58 and l2Oph injection, respectively. 44.7~68.9% of the treated embryos developed to 4-cell stages at 58hph. Only 17.6~60.3% of the embyos developed upto blastocyst at l20hph. Whereas control embryos showed slightly lower development in M16 medium alone (38.9~42.4%, 4-cell and 3.8~65.5%, blastocyst). Three mitogenic agents were tested. 51.6~63.8% and 43.4~48.1% of embryos developed up to 2-cell and blastocyst stage, respectively when treated in 5 g PHA-M Imi for 5 min, 1, 3 and 6h subsequently cultured in fresh M16 medium. Control embryos only showed 38.8% for 4cell and 5.9% fo blastocyst at 58 and l2Ohph, respectively. 100M PMA was also beneficial for the 2-cell block. Showing better development them that of control (42.4 vs 57.9~59.4% 4cell and 5.9 vs 25.0~55.6% blastocyst, respectively. However 1M butyric acid was toxic to early embryos, thus arresting further development. These result indicate that either chelating or mitogenic agents could be used to overcome the "in vitro 2-cell block" occuring during early development in vitro of ICR embryosCR embryos
무전해 동도금액에서의 각종 안정제, 촉진제등의 첨가제에 따른 영향을 고찰하였다. 욕의 기본성분은 황산구리 10g/1, EDTA-2Na 40g/1, 포르말린 3ml/1, pH조절용 수산화나트륨 용액으로 조성하였고, 안정제, 도금촉진제 및 계면활성제의 첨가에 따른 분극곡선을 검토하여 도금욕의 경향을 검토한뒤 농도변화에 따른 도금속도를 측정하여 최적조건을 구하였다. 안정제는 α, α'-dipyridy1과 NaSCN을 혼합 사용하는 것이 좋았으며 촉진제로는 pyridine이 계면활성제로는 PEG 4000이 좋았다. 첨가량은 5mg/1이하의 미량이었으며 이후 첨가량이 증가함에 따라 증가함에 따라 도금속도는 직선적으로 감소하였다.
In the preparation of acrylic water repellent(EDLWC). quaternized 2-diethylarrunoethylmethacrylate-stearylmethacrylate copolymer (DSACC) and quaternized 1-Iaurovlbis(aminoethyl)-2-dodecylimidazoline(LDDIC) were selected as a basic resin and the improving agent such as softening effect and hydrostatic pressure of the water repellent. EDLWC was prepared by blending waxes and emulsifier for waxes with various ratio to DSACC and LDDIC. As the results of the measurement of water repellency, washable, tear strength and crease recovery to polyester-cotton(P/C) blended fabrics treated with EDLWC only or addition of textile finishing resin, the physical properties were increased. Sodium acetate was the most effective catalyst in the water repellency among the various kinds of catalyst. and the reasonable concentration of the catalyst was 1. 4 wt%. EDLWC was confirmed as durable water repellent with the results of making little difference of water repellency as ±5 point after and before washing. The reaction mechanism between P/C blended fabrics and EDLWC in the presence of catalyst was proposed. And also, the longitudinal view of the P/C blended fabrics treated with water repellent was observed with scanning electron microscope.
An experiment was conducted to determine the feeding value of Arundinella hirat silage making by different methods ie., added starch 3%, formic acid 1% (FA), anhydrous ammonia (NH3) 3%, and dried poultry waste (DPW) 3%. The samples were analyzed organi
The quaternized compound of the copolymer between 2-diethylaminoethyl methacrylate and stearyl methacrylate (DSACC) was chosen as the mother resin for the water repellent of acrylics. The quaternized compound of 1-lauroyl dis (amino ethyl)-2-dodecyl imidazoline (LDDIC) was used to promote softening effect and hydrostatic pressure for the water repellent. The water repellent (EDUWC) obtained from the DSACC and LDDIC blended with waxes and emulsifiers improved the properties such as the water repellency, washable, tear strength and crease recovery when it was treated on the nylon fabrics with and without the resin. The reaction mechanism between the Nylon fiber and EDLWC was examined, and EDLWC was confirmed as the durable water repellent.
This study was carried out to determine the effects of nitrogen (N) fertilization levels (0, 100 and 200kg/ha) and formaldehyde (0.4,0.8 and 1.2%: w/w CM) on the chemical composition, dry matter (DM) yield and in-vitro dry matter digestibility (IVDMD) of
Insufficient herbage during the fall in the temperate areas of the world has been a serious limitation in animal production, but leafy brassicae are potentially very useful for extending the grazing season when the growth and quality of grass is poor. Thi
This study aimed to investigate the effect of amino acid additives to weaned piglet diets on the pH and volatile fatty acids of pig slurries. A total of 135 weaned 22 -day-old piglets (Yorkshire x Landrace x Duroc) were used in this 56-d study. The three dietary treatments were as follows: (1) Control as a basal diet, (2) 1% amino acid additive and (3) 2% amino acid additive. Both pH and acetic acid values at 71 and 78 days were significantly different in all treatment groups (p<0.05). In addition, significant differences in propionic acid values were observed among treatment groups at 64 and 78 days (p<0.05). However, pH, acetic acid, and propionic acid values did not differ between 1% and 2% amino acid treatment groups. In conclusion, adding 1% and 2% amino acid to weaned piglet diets reduced the pH, acetic acid and propionic acid contents of pig slurries by acting as a probiotic. This may help formulate increase management strategies for improving the pig housing environment.