• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.415-423
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• 1996

Thin film technologies for fabricating SQUIDs involve etching and deposition procedures with the proper substrate materials and $YBa_2Cu_3O_{7-d}$ (YBCO) as the high $T_c$ superconductor. YBCO were prepared on various substrates of MgO, $SrTiO_3$, and $LaAlO_3$ by using off-axis magnetron sputtering methods and annealing in-situ. The parameters of film fabrication processes had been optimized to yield good quality films in terms of the critical temperature $T_c$ and the critical current density $J_c$. The optimized processes yielded $T_C$>90K along with $J_c$>$10_6A$$extrm{cm}^2$ at 77K and>$2\times10_7A/Cm^2$ at 5K. We fabricated step-edge type dc-SQUIDs and directly coupled magnetometers, producing step edges on MgO(100) substrates by etching with Ar-ion beam, depositing YBCO material on them, then patterning them by using ion-milling technique. Circuitizing washer-shape SQUIDs to possess a pair of step-edge junctions of 2-5$\mu$ line width with a high angle>$50^{\circ}C$ , we examined their I-V characteristics thoroughly and Shapiro steps clearly as we irradiate microwaves of 8-20 GHz frequency.

• Applied Biological Chemistry
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• v.31 no.1
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• pp.1-6
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• 1988

The degermed Japonica and J/Indica brown rites were abrasively milled to give an average yield for each milling of about 5% flour, with 85% of the rice left as residual kernel. The contents of protein, fat and ash were in the highest in fraction I and decreased with each successive milling. The fraction I contained twice as much protein as did the original kernel, 5.7 times as much ash and 11.4 times as much fat. However, no significant differences in the distribution among varieties were noticed. Residual kernels contained 68.7% of protein, 5.1% of fat and 41.8% of ash in the original kernel.

• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.521-527
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• 1989

This study was conducted to investigate the differneces in milling, physicochemical, rheological and end-product properties between Korean and American wheat cultivars. Also, rheological and bread baking properties of Korean wheat flour in blends with U.S. standard flour were investigated. The milling yield of Korean wheat rated 71.1% similar to 71.6% of U.S. wheat. The average AWRC 61.8% of the three Korean wheats ranked higher than the conventional value of 60% for classifying hard and soft wheat. The cookies made from Korean wheat flour showed comparatively good spread with diameter of 8.5-8.9 cm, and marked recommendable top grain score. The volume ranges 975-1175 cc of sponge cake made from all cultivars tested were lower about 4-26% than that of standard cake flour. especially, Wonkwang was selected as one which has special characteristics good for cookie and sponge cake. The volumes of breads from Korean wheat 리ours ranged 924-1020 cc, and Yongkwang of 1020cc marked the most appropriate characteristics for bread-making among the tested wheats. The proper blending ratio of Korean wheat flour to U.S. bread standard flour was revealed 30% in bread-making.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.17
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• pp.1-44
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• 1974

These studies were made at Suwon in 1972 and at Suwon, Iri, and Kwangju in 1973 to investigate grain filling process and variation of grain quality of NB 68513 and Caprock as hard red winter wheat, Suke ＃169 as soft red winter wheat variety and Yungkwang as semi-hard winter variety, grown under-three different fertilizer levels and seeding dates. Other experiments were conducted to find the effects of temperature, humidity and light intensity on the grain filling process and grain quality of Yungkwang and NB 68513 wheat varieties. These, experiments were conducted at Suwon in 1973 and 1974. 1. Grain filling process of wheat cultivars: 1) The frequency distribution of a grain weight shows that wider distribution of grain weight was associated with large grain groups rather than small grain group. In the large grain groups, the frequency was mostly concentrated near mean value, while the frequency was dispersed over the values in the small grain group. 2) The grain weight was more affected by the grain thickness and width than by grain length. 3) The grain weight during the ripening period was rapidly increased from 14 days after flowering to 35 days in Yungkwang and from 14 days after flowering to 28 days in NB 68513. The large grain group, Yungkwang was rather slowly increased and took a longer period in increase of endosperm ratio of grain than the small grain group, NB 68513. 4) In general, the 1, 000 grain weight was reduced under high temperature, low humidity, while it was increased under low temperature and high humidity condition, and under high temperature and humidity condition. The effect of shading on grain weight was greater in high temperature than in low temperature condition and no definite tendency was found in high humidity condition. 5) The effects of temperature, humidity and shading on 1, 000 grain weight were greater in large-grain group, Yungkwang than in small grain group, NB 68513. Highly significant positive correlation was found between 1, 000 grain weight and days to ripening. 6) The 1, 000 grain weight and test weight were increased more or less as the fertilizer levels applied were increased. However, the rate of increasing 1, 000 grain weight was low when fertilizer levels were increased from standard to double. The 1, 000 grain weight was high when planted early. Such tendency was greater in Suwon than in Kwangju or Iri area. 2. Milling quality: 7) The milling rate in a same group of varieties was higher under the condition of low temperature, high humidity and early maturing culture which were responsible for increasing 1, 000 grain weight. No definite relations were found along with locations. 8) In the varieties tested, the higher milling rate was found in large grain variety, Yungkwang, and the lowest milling rate was obtained from Suke ＃ 169, the small grain variety. But the small grained hard wheat variety such as Caprock and NB 68513 showed higher milling rate compared with the soft wheat variety, Suke ＃ 169. 9) There were no great differences of ash content due to location, fertilizer level and seeding date while remarkable differences due to variety were found. The ash content was high in the hard wheat varieties such as NB 68513, Caprock and low in soft wheat varieties such as Yungkwang and Suke ＃ 169. 3. Protein content: 10) The protein content was increased under the condition of high temperature, low humidity and shading, which were responsible for reduction of 1, 000 grain weight. The varietal differences of protein content due to high temperature, low humidity and shading conditions were greater in Yungkwang than in NB 68513. 11) The high content of protein in grain within one to two weeks after flowering might be due to the high ratio of pericarp and embryo to endosperm. As grains ripen, the effects of embryo and pericarp on protein content were decreased, reducing protein content. However, the protein content was getting increased from three or four weeks after flowering, and maximized at seven weeks after flowering. The protein content of grain at three to four weeks after flowering increased as the increase of 1, 000 grain weight. But the protein content of matured grain appeared to be affected by daily temperature on calender rather than by duration of ripening period. 12) Highly significant positive correlation value was found between the grain protein content and flour protein content. 13) The protein content was increased under the high level of fertilizers and late seeding. The local differences of protein content were greater in Suwon than in Kwangju and Iri. 14) Protein content in the varieties tested were high in Yungkwang, NB 68513 and Caprock, and low in Suke ＃ 169. However, variation in protein content due to the cultural methods was low in Suke ＃ 169. 15) Protein yield per unit area was increased in accordance with increase of fertilizer levels and early maturing culture. However, nitrogen fertilizer was utilized rather effectively in early maturing culture and Yungkwang was the highest in protein yield per unit area. 4. Physio-chemical properties of wheat flour: 16) Sedimentation value was higher under the conditions of high temperature, low humidity and high levels of fertilizers than under the conditions of low temperature, high moisture and low levels of fertilizers. Such differences of sedimentation values were more apparent in NB 68513 and Caprock than Yungkwang and Suke ＃ 169. The local difference of sedimentation value was greater in Suwon than in Kwangju and Iri. Even though the sedimentation value was highly correlated with protein content of grain, the high humidity was considered one of the factors affecting sedimentation value. 17) Changes of Pelshenke values due to the differences of cultural practices and locations were generally coincident with sedimentation values. 18) The mixing time required for mixogram was four to six minutes in NB 68513, five to seven minutes in Cap rock. The great variation of mixing time for Yungkwang and Suke ＃ 169 due to location and planting conditions was found. The mixing height and area were high in hard wheat than in soft wheat. Variation of protein content due to cultural methods were inconsistent. However, the pattern of mixogram were very much same regardless the treatments applied. With this regard, it could be concluded that the mixogram is a kind of method expressing the specific character of the variety. 19) Even though the milling property of NB 68513 and Caprock was deteriorated under either high temperature and low humidity of high fertilizer levels and late seeding conditions, baking quality was better due to improved physio-chemical properties of flour. In contrast, early maturing culture deteriorated physio-chemical properties, milling property of grain and grain protein yield per unit area was increased. However, it might be concluded that the hard wheat production of NB 68513 and Caprock for baking purpose could be done better in Suwon than in Iri or Kwangju area. 5. Interrelationships between the physio-chemical characters of wheat flour: 20) Physio-chemical properties of flour didn't have direct relationship with milling rate and ash content. Low grain weight produced high protein content and better physio-chemical flour properties. 21) In hard wheat varieties like NB 68513 and Caprock, protein content was significantly correlated with sedimentation value, Pelshenke value and mixing height. However, gluten strength and baking quality were improved by the increased protein content. In Yungkwang and Suk ＃ 169, protein content was correlated with sedimentation value, but no correlations were found with Pelshenke value and mixing height. Consequently, increase of protein content didn't improve the gluten strength in soft wheat. 22) The highly significant relationships between protein content and gluten strength and sedimentation . value, and between Pelshenke value, mixogram and gluten strength indicated that the determination of mixogram and Pelshenke value are useful for de terming soft and hard type of varieties. Determination of sedimentation value is considered useful method for quality evaluation of wheat grain under different cultural practices.

• Applied Biological Chemistry
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• v.35 no.6
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• pp.475-478
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• 1992

Series of study were conducted to investigated the condition of wet polishing and quality of wet polished rice. The optimal condition for wet polishing was determined to be 0.5% added water after removal bran layer of 95% by normal milling. Its polishing yield was 0.75% lower than normal polishing, and the moisture content of wet and normal polished rice was the same, but the whiteness of wet polished rice was higher by 3.5% than that of normal polished rice and the lightness was very good. The total solid as washing wet polished rice in water and the total solid in residual liquid of cooked wet polished rice was about 0.30 and 2% lower than those of normal polished rice, respectively. The storability of wet polished rice was better than that of normal polished rice.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.301-306
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• 1997

This study is presented to investigate the physico-chemical properties and qualities for the starch isogenic lines bred in barley(Hordeum vulgare L.).The pearling yield showed higher value in Franubet and Wafranubet than others, but the whiteness of pearled barley varied with the cultivars. The milling rate showed excellence in Franubet, fractured granular lines, whereas that of the waxy and round endosperm isogenic lines is poor. Franubet, the lines having fractures starch granule, was highest in starch content. The highest value in swelling power and water-binding capacity of the barley was proved by the lines having waxy and fractured starch endosperms. The amylogram patterns indicated that the waxy lines such as Wanubet and Wafranubet have lower initial gelatinization temperature and higher maximum viscosity than those of the normal lines. ${\beta}-Glucan\;viscosity$ was generally higher in waxy barley but changed greatly with the cultivars. The water absorption, soluble solid and expansibility in cooking property showed the highest value in waxy and fractured starch granular lines, and the whiteness of cooked barley did not differ with cultivars.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05c
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• pp.166-169
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• 2003

In this study, we evaluated the characteristics by the addition of 3 different kinds of nonionic surfactant to improve the dispersion stability of slurries. Slurry stability is an issue in any industry in which settling of particles can result in poor performance. So we observed the variation of particle size and settling rate when the concentration and addition time of surfactant are changed. When the surfactant is added after milling process, the particle size and pH became low. It is supposed that the particle agglomeration was disturbed by adsorption of surfactant on alumina abrasive. The settling rate was relatively stable when nonionic surfactant is added about 0.1~1.0 wt%. When molecular weight(MW) is too small like Brij 35, it was appeared low effect on dispersion stability. Because it can't prevent coagulation and subsequent settling with too small MW. The proper quality of MW for slurry stability was presented about 500,000. Consequently, the addition of nonionic surfactant to alumina slurry has been shown to have very good effect on slurry stabilization. If we apply this results to copper CMP process, it is thought that we will be able to obtain better yield.

• Journal of Powder Materials
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• v.28 no.3
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• pp.221-226
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• 2021

We fabricate the non-equiatomic high-entropy alloy (NE-HEA) Fe_49.5Mn₃₀Co₁₀Cr₁₀C_0.5 (at.%) using spark plasma sintering under various sintering conditions. Each elemental pure powder is milled by high-energy ball milling to prepare NE-HEA powder. The microstructure and mechanical properties of the sintered samples are investigated using various methods. We use the X-ray diffraction (XRD) method to investigate the microstructural characteristics. Quantitative phase analysis is performed by direct comparison of the XRD results. A tensile test is used to compare the mechanical properties of small samples. Next, electron backscatter diffraction analysis is performed to analyze the phase fraction, and the results are compared to those of XRD analysis. By combining different sintering durations and temperature conditions, we attempt to identify suitable spark plasma sintering conditions that yield mechanical properties comparable with previously reported values. The samples sintered at 900 and 1000℃ with no holding time have a tensile strength of over 1000 MPa.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.213-213
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• 2022

Pre-harvest sprouting(PHS) refers to germinating seeds in the mother plant before harvesting under low dormancy and humid climate, deteriorating grain quality, and rice yield. Rice varieties with floury endosperm(RFE) have been developed to boost domestic rice consumption by invigorating the processed rice industry, reducing milling and environmental cost. However, the PHS tolerance of RFE is relatively low in the rice varieties with transparent endosperm(RTE) since they soak moisture rapidly due to soft endosperm. In this study, Baromi2(BR2), floury endosperm, and Jomyeong1(JM1), PHS tolerance donor, were crossed to improve PHS tolerance. Major agronomic traits and PHS tolerance test of ten F₇(BR2/JM1) lines were conducted in NICS, 2022. The evaluations of PHS were carried out according to the method of RDA(2012) with slight modifications. Briefly, three panicles were treated and incubated 25℃ in a growth chamber 35 days after the heading date. Ten PHS tolerance promising lines demonstrated floury endosperm. The heading date of BR2 and JM1 was 7/27 and 8/5, respectively. The heading date of promising lines was 7/23~8/10. The PHS rate of BR2 and JM1 exhibited 56.3% and 10.7%, respectively. However, the PHS rate often promising lines demonstrated 2.4%~52.4%, 3 lines significantly lower than BR2. Further studies such as ABA contents are necessary to elucidate the mechanism of PHS tolerance in BR2/JM1. These results may contribute to developing elite RFE lines with improved PHS tolerance.

• Journal of Powder Materials
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• v.30 no.6
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• pp.484-492
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• 2023

In this study, Ni-Y₂O₃ powder was prepared by alloying recomposition oxidation sintering (AROS), solution combustion synthesis (SCS), and conventional mechanical alloying (MA). The microstructure and mechanical properties of the alloys were investigated by spark plasma sintering (SPS). Among the Ni-Y₂O₃ powders synthesized by the three methods, the AROS powder had approximately 5 nm of Y₂O₃ crystals uniformly distributed within the Ni particles, whereas the SCS powder contained a mixture of Ni and Y₂O₃ nanoparticles, and the MA powder formed small Y₂O₃ crystals on the surface of large Ni particles by milling the mixture of Ni and Y₂O₃. The average grain size of Y₂O₃ in the sintered alloys was approximately 15 nm, with the AROS sinter having the smallest, followed by the SCS sinter at 18 nm, and the MA sinter at 22 nm. The yield strength (YS) of the SCS- and MA-sintered alloys were 1511 and 1688 MPa, respectively, which are lower than the YS value of 1697 MPa for the AROS-sintered alloys. The AROS alloy exhibited improved strength compared to the alloys fabricated by SCS and conventional MA methods, primarily because of the increased strengthening from the finer Y₂O₃ particles and Ni grains.