• Journal of the Korean Wood Science and Technology
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• 제24권1호
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• pp.17-26
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• 1996

This research was accomplished to evaluate possibility of using paper sludge for the raw materials of wood based panel products. The experimental panels were manufactured by four mixed ratios, the proportion of paper sludge to wood particle: 20:80, 30:70, 40:60, 50:50% (oven dry weight basis) and by three composition types, sludge-particle mixed board, three layered sludge-particle board and three layered particle board. They were tested mechanical (bending strength and internal bond) and physical properties (water absorption, thickness swelling and linear expansion). From the results they were shown that bending strength of mixed and three layered sludge-particle board were decreased with increasing of composition ratios of sludge. And the mechanical and physical properties of the boards of three layered composition types have superior to those of mixed composition type. Although composition ratios of sludge increased, the internal bond strength and dimensional stability of sludge-particle board not decreased quantitatively. We concluded that the mechanical and physical properties of three layered sludge-particle board were similar w those of three layered particle-board (control) made by our laboratory design. Therefore, it was recognized that paper sludge can be used as potential raw material in particle-board manufacturing industry.

• Nuclear Engineering and Technology
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• 제50권1호
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• pp.140-144
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• 2018

Isotopic analyses of plutonium and low-enriched uranium mixtures with particle sizes of $0.6-3.3{\mu}m$ were performed using thermal ionization mass spectrometry with a continuous heating method to verify its effectiveness for the accurate analysis of minor isotopes without sample pretreatment. The mixed particles used in this study were prepared from a mixed solution of plutonium (SRM 947) and uranium (U010, $^{235}U$ 1% enriched) reference materials. The isotope ratios for plutonium in the individual mixed particles, including $^{238}Pu/^{239}Pu$, $^{241}Pu/^{239}Pu$ as well as $^{240}Pu/^{239}Pu$, and $^{242}Pu/^{239}Pu$, were in good agreement with the certified values despite the isobaric interference of $^{238}U$ and $^{241}Am$. The isotope ratios for uranium in the mixed particles also agreed well with the certified values within the range of error. However, the isotope ratios for minor isotopes, such as $^{234}U$ and $^{236}U$, in the particles with diameters of less than approximately $1.8{\mu}m$ could not be measured because numbers of $^{234}U$ and $^{236}U$ atoms in analyzed particles are too low. These results indicate that thermal ionization mass spectrometry with a continuous heating method is applicable for the analysis of trace amounts of plutonium isotopes, including $^{238}Pu$ and $^{241}Pu$, despite the presence of the respective isobars $^{238}U$ and $^{241}Am$ in the microsamples.

• Journal of Ecology and Environment
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• 제42권4호
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• pp.174-182
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• 2018

Background: In this study, we observed their growth and physiological responses using a variety of duty ratio under the mixed light using red, blue, and white lights. The red+blue mixed light was treated with 95%, 90%, 85%, 80%, and 75% duty ratios and red+blue+white mixed light with 85% and 70% duty ratios. We examined the width and length of leaves, total number of leaves, and number of shoots to examine their growth responses. The physiological responses were studied by measuring their photosynthetic rate, transpiration rate, stomatal conductance, water use efficiency, chlorophyll content, and fluorescence ($F_o$, $F_m$, and $F_v/F_m$). Results: We found that lower duty ratio caused the length and width of the leaves to grow longer under red+blue mixed light but that it did not cause any difference in the red+blue+white mixed light condition. In addition, there was no difference in the number of leaves and shoots among all treatments. In the red+blue mixed light condition, the photosynthetic rate was no difference, but both transpiration rate and stomatal conductance were the highest at 95% duty ratio than in other ratios. Water use efficiency pattern was similar to that of photosynthetic rate; water use efficiency was no difference. Chlorophyll content was the highest at 95% duty ratios, and it was the least at 90%, 85%, and 75% duty ratio. $F_o$ and $F_m$ values were relatively high at 85% and 80% duty ratio and low at 90% duty ratio while $F_v/F_m$ showed no difference. Conclusions: Under the red+blue+white mixed light, all physiological items showed no difference between 70 and 85% treatments. But, photosynthetic rate, water use efficiency, chlorophyll content, and $F_v/F_m$ were relatively greater in the red+blue+white mixed light than in the red+blue mixed light. Therefore, red+blue+white mixed light treated with 70% duty ratio could lessen the environmental stress and save more power when cultivating Silene capitata in a plant factory.

• Journal of the Korean Wood Science and Technology
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• 제27권4호
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• pp.57-64
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• 1999

This research was carried out to investigate the effects of density, resin and particle types on the physical and mechanical properties of the composites made from various wood particles mixed with coating paper. The experiment was designed to apply with three particles (flake, chip, and fiber) and three resin types (urea, phenol and PMDI resin). The mixed ratio of coating paper to wood particle was fixed on 50 to 50% in each board making. And also it was designed to apply for four density levels (0.6, 0.7, 0.8 and 0.9 g/$cm^3$) and four mixed formulations of coating paper to wood particle (10:90, 20:80, 30:70, and 40:60 %) to analyze clearly the effects of PMDI resin. Coating paper-wood particle composites have acceptable bending strength (MOR, MOE) though the mixed ratio of coating paper was increased, but have low internal bond strength and poor dimensional stability (WA, TS, LE). Composites with high density had higher mechanical properties but showed lower physical properties than composites with low density. In conclusion, at least up to 20% mixed ratios, coating paper-wood particle composites have acceptable physical and mechanical properties, and PMDI resin has possibility for coating paper-wood particle composite manufacture.

• 동아시아식생활학회지
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• 제15권5
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• pp.582-590
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• 2005

The application of consomme prepared with different ratios of ground beef and ground chicken to improve taste preferences and the cost of foodstuffs was attempted by reviewing fundamental data and the effect on the sensory and physical characteristics of treatment These treatments were prepared with different ratios(9:1(A), 7:3(B), 5:5(C), 3:7(D), 1:9(E) w/w) of ground beef and ground chicken, respectively. Sensory properties were evaluated in the aspects of both acceptability and intensity. From the acceptability aspect, A treatment showed the highest scores in smell, B in mouthfeel and taste, A and B in color and overall acceptability, respectively. In terms of acceptability, B treatment was favored most for color, mouthfeel, taste and overall acceptability except smell. The more the ground chicken, the higher the intensity aspect E treatment showed higher values than A in all the intensity aspects. Moisture contents and crude proteins increased by increasing the mixed ratio of ground beef, whereas crude ash, solid matter and pH increased by increasing the mixed ratio of ground chicken. Tumidity values were the highest in E treatment, whereas the lowest in A. Tumidity values were increased significantly by increasing the mixed ratio of ground chicken. Viscosity increased by increasing the mixed ratio of ground chicken. The highest viscosity was shown in E treatment The colorimetric lightness values(L) decreased and redness(a), yellowness(b) and total color difference values(AE) increased significantly by increasing the mixed ratio of ground chicken. This experimental study showed that A and B treatment had the highest values in overall acceptability. The results of analysis in crude protein, solid matter, tumidity and viscosity were increased by increasing the mixed ratio of ground chicken. B treatment prepared with a ratio of 7:3 of ground beef and chicken had the most favorable sensory quality. These results suggested the basic information to improve acceptability and to save the costs of Consomme recipes for foodservice institutions.

• 한국작물학회지
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• 제60권4호
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• pp.458-463
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• 2015

사료용으로 개발된 청보리 품종들은 일반 곡실용 보리품종에 비해 조사료 생산량이 30%이상 증수하고 가축선호성이 우수한 품종이다. 이러한 사료용 전용품종을 이용하여 품종이 가지고 있는 생육특성별 단점을 보완한 품종간 혼파 재배기술의 개발을 통한 군락공간의 최대 활용 및 영양가치 등을 고려한 단위면적당 생산량을 최대화하는데 목적이 있다. 영양보리는 직립초형이고 다수성이며, 유연보리는 삼차망이면서 키가 크고, 다미보리는 무엽이 특성이 있고, 우호보리는 포복형이면서 키가 크고 매끈망을 지니고 있다. 소만보리는 숙기가 빠르고, 분얼이 많은 특성이 있다. 2조보리인 호품보리는 청보리에 비해 등숙이 빠르고 분얼이 많은 장점을 가지고 있다. 이러한 각기 다른 특성을 지닌 품종을 이용하여 청보리 최적 혼파 조합을 선발하고자 시험조사한 결과, 영양50+호품50 조합, 유연70+호품30 조합, 다미50+호품50 조합이 가장 좋았고, 이 중 가장 높은 생산성을 보인 조합은 유연70+호품30 조합이었다. 품질특성면에서는 조단백함량이 높고, NDF와 ADF 수치가 낮고, TDN 수치가 높을수록 좋은 품질로 인정받는데 품종간의 조합 중 유연보리와 호품보리, 다미보리와 호품보리 조합이 우수한 성적을 나타냈다.

• Elastomers and Composites
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• 제55권4호
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• pp.281-288
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• 2020

A calibration curve is needed to determine the SBR and BR blend ratio of SBR/BR blend rubber compounds using pyrolysis-gas chromatography/mass chromatography (Py-GC/MS) or Py-GC. In general, a calibration curve is obtained using reference SBR/BR vulcanizates with various blend ratios. In this study, the calibration curves were obtained using reference samples made of rubber solutions and were compared to those plotted using the reference SBR/BR vulcanizates. Calibration curves using variations of 1,3-butadiene/styrene, 4-vinylcyclohexene (VCH)/styrene, 2-phenylpropene (PhP)/butadiene, PhP/VCH, 4-phenylcyclohexene (PhCH)/butadiene, and PhCH/VCH ratios with the BR content were examined for the suitability. We found that the calibration curves obtained using the mixed rubber solution references (1,3-butadiene/styrene and PhP/butadiene) could replace those constructed using the reference SBR/BR vulcanizates. The calibration curves of 1,3-butadiene/styrene and PhP/butadiene obtained using the raw references can be used for the determination of the SBR/BR blend ratios by applying some correction factors.

• Journal of the Korean Wood Science and Technology
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• 제42권4호
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• pp.420-427
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• 2014

제재과정에서 발생되는 톱밥과 농업부산물인 왕겨의 활용방안을 찾고자 왕겨의 혼합비율에 따라 혼합보드를 제조하고 수지함침 및 탄화과정을 거쳐 혼합세라믹을 제조하여 왕겨의 혼합비율에 따라 물성을 조사하였다. 같은 수지함침율에서 왕겨혼합비율이 증가함에 따라 탄화 후 밀도 및 휨강도는 증가하였으나 중량감소율은 감소하였다. 또한 같은 탄화온도에서 밀도와 휨강도는 왕겨혼합비율이 40%일 때 가장 큰 것으로 나타났다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.217-222
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• 2002

The purposes of this study are to investigate the material characteristics and strength properties of concrete mixed with waste incinerated bottom ash(BA), and to evaluate the leaching of environmentally harmful heavy metals from the bottom ash itself and from hardened concrete mixed with bottom ash. For this purpose, two reference mixes with W/C ratios of 0.45 and 0.55 were used, and the replacement proportion of BA was varied with the ratios of 0%, 30%, 50%, 70%, and 100% by volume of fine aggregate in the reference mixes. The variation of compressive and splitting tensile strength, workability and unit weight of concrete were considered. Test results showed that the strengths, workability and unit weight decreased with increase in proportion of BA replaced. Leaching test results showed that there would be no environmentally harmful problem from using BA as the substitutes of fine aggregates in concrete.

• 생태와환경
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• 제52권2호
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• pp.171-177
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• 2019

Smart farm is a breakthrough technology that can maximize crop productivity and economy through efficient utilization of space regardless of external environmental factors. This study was conducted to investigate the optimal growth and physiological conditions of Chinese matrimony vine (Lycium chinense) with LED light sources in a smart farm. The light source was composed of red+blue and red+blue+white mixed light using a LED system. In the red+blue mixed light, red and blue colored LEDs were mixed at ratios of 1:1, 2:1, 5:1, and 10:1, with duty ratios varied to 100%, 99%, and 97%. The experimental results showed that the photosynthetic rate according to the types of light sources did not show statistically significant differences. Meanwhile, the photosynthetic rate according to the mixed ratio of the red and the blue light was highest with the red light and blue LED ratio of 1:1 while the water use efficiency was highest with the red and blue LED ratio of 2:1. The photosynthetic rate according to duty ratio was highest with the duty ratio of 99% under the mixed light condition of red+blue+white whereas the water use efficiency was highest with the duty ratio of 97% under the mixed light of red+blue LED. The results indicate that the light source and light quality for the optimal growth of Lycium chinense in the smart farm using the LED system are the mixed light of red+blue (1:1) and the duty ratio of 97%.