• 한국재료학회지
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• 제31권1호
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• pp.1-7
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• 2021

The characteristics and morphology of precipitated calcium carbonate (PCC) particles produced by carbonation process with various experimental conditions are investigated in this study. The crystal structures of PCC formed by carbonation process are calcite and aragonite. The crystal structure of PCC particles synthesized without adipic acid additive is calcite only, regardless of the reaction temperature. Needle-like shape aragonite phase started to form at reactor temperature of 80℃ with the adipic acid additive. Particle size of the single phase calcite PCC synthesized without adipic acid additive is about 1 ~ 3 ㎛, with homogenous distribution. The aragonite PCC also shows uniform size distribution. The reaction temperature and concentration of adipic acid additive do not show any significant effects on the particle size distribution. Aragonite phase grown to a large aspect ratio of needle-like shape showed relatively improved whiteness. The measured whiteness value of single calcite phase is about 95.95, while that of the mixture of calcite and aragonite is about 99.11.

• 한국육종학회지
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• 제41권3호
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• pp.299-305
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• 2009

신품종 "진주찰" 쌀보리는 취반 후 백도가 좋고, 베타글루칸 함량이 높은 소립, 내재해, 양질, 다수성 쌀보리 신품종이다. 1996년에 호남농업연구소에서 도복과 내한성이 강하고 찰성으로 립백도와 정맥율이 높으며 취반특성이 우수한 특성을 지닌 "진미찹쌀보리"와 "수원333호"를 인공교배한 후 계통육종법으로 육성하였다. 2003년부터 2년간 생산력검정시험을 실시한 결과, 수량성이 높고 도복이 강한 우수 계통으로 판명되어 "익산79호"로 계통명을 부여, 2005년부터 3년간 전작재배 수원 등 3개 지역, 답리작재배 익산 등 4개 지역에서 지역적응시험을 실시하였다. 그 결과, 답리작 적응성이 높으며, 도복 등 내재해성에 강한 특성과 $\beta$-glucan 함량이 높고, 총페놀과 proanthocyanidin 함량이 낮아 취반 후 갈변화가 적고 백도가 높은 계통임이 입증되어 2007년 농작물 직무육성 신품종선정심의회에서 신품종 "진주찰"로 등록하게 되었으며 그 특성은 다음과 같다. 1. 진주찰쌀보리는 새찰쌀보리에 비해 보리호위축병, 내한성 및 도복에 강하다. 2. 출수기는 전작 5월 4일로 새찰쌀보리보다 2일 늦었으며, 답리작은 4월 27일로 새찰쌀보리와 같았다. 성숙기는 전작 6월 6일, 답리작 6월 1일로 새찰쌀보리에 비해 1~3일 늦은 품종이다. 3. 간장은 81 cm로 중장간, 수장 4.9 cm, 일수립수 56개로 새찰쌀보리보다 적었고 $m^2$당 수수는 673개로 많았고 천립중은 27.0 g으로 소립종이었다. 4. 품질의 조곡특성은 단백질 함량은 11.9%로 새찰쌀보리와 비슷하였으며, $\beta$-glucan 함량은 8.4%로 새찰쌀보리 보다 높았으며, 정곡특성은 정맥율이 76.4%로 높았으며, 립백도 36.1로 새찰쌀보리에 비해 2.1정도 낮았다. 5. 취반 시 수분 흡수율은 249%로 높았으나 퍼짐성은 새찰쌀보리보다 다소 낮았고 총페놀과 프로안토시아니딘 함량 은 정곡에서 4.2와 0.2 mg/g으로 새찰쌀보리 보다 낮았으며 보리밥 백도는 취반 24시간 후와 53시간 후에서 24.8, 20.3으로 새찰쌀보리 보다 높았다. 6. 수량성은 전작재배 3.79 MT/ha으로 새찰쌀보리보다 1% 감수하였으나 답리작 재배 3.73 MT/ha으로 3% 증수하였다. 7. 적응지역은 대전이남 1월 평균 최저기온이 $-6^{\circ}C$ 이남지역과 쌀보리 재배지, 보리호위축병이 상습 발생하는 지역에 권장된다.

• 한국식품영양과학회지
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• 제33권10호
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• pp.1676-1684
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• 2004

어육, 닭 가슴살 및 돼지 후지 육을 산성 및 알칼리 용액으로 추출하여 등전점 부근에서 회수하고 중성 부근의 pH로 재조절하여 회수한 단백질의 가열 젤 물성과 이들의 혼합에 따른 가열 물성 값의 변화, 최적 물성과 최소비용을 제공하는 혼합 비율을 결정하였다. 갈고등어의 근원섬유단백질은 산 및 알칼리 처리에 의해 가열 젤을 형성하지 못하였으나, 산과 알칼리 처리후 근형질 단백질을 포함한 회수 단백질은 가열 젤을 형성하였다. pH 10.5에서 처리 후 회수한 단백질의 가열 젤의 파괴강도는 갈고등어가 가장 낮았고, 변형 값은 냉동 꼬마민어>닭 가슴살>돼지 후지 육>갈고등어의 순으로 높았으며, 백색도는 냉동 꼬마민어 회수 단백질이 가장 높았다. 갈고등어 회수 단백질의 첨가는 파괴강도, 변형 값, 백색도를 감소시키고 가격을 상승시키는 반면, 닭 가슴살 회수 단백질의 첨가는 파괴 강도와 백 색도를 다소 증가시키고 가격을 현저히 감소시켰다. 냉동 꼬마민어 회수 단백질인 경우, 파괴강도 110 g 이상, 변형 값 4.5 mm 이상 및 회수 단백질의 원료 단가 2000원 이하/kg을 만족하는 최적 혼합 비율은 냉동 꼬마민어 36∼50%, 닭 가슴살 34∼40%, 돼지 후지 육 14∼25%이었다 가열 젤의 구조는 냉동 꼬마민어 회수 단백질이 가장 치밀하였다. 냉동 꼬마민어 회수 단백질을 축으로 닭 가슴살, 돼지 후지 육 회수 단백질의 적절한 혼합 비율의 조절은 물성 값이 다양화한 연제품에 활용 가능할 것으로 판단된다.

• 한국의류학회지
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• 제30권7호
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• pp.1025-1033
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• 2006

Kenaf bast can be obtained by decortication of Kenaf stem. Kenaf fibers are much more rough than cotton fiber because they include impurities as pectin, lignin and hemicellulose besides cellulose. The purpose of this research is to investigate the distribution of kenaf fiber length and diameter during the processes of removing impurities. To remove pectin, kenaf bast was retted chemically. A half of the retted kenaf fiber bundle were scoured and bleached. The other half one were treated with $NaClO_2$ solution to remove lignin, and were treated with sodium hydroxide solution to remove hemicellulose. Four kinds of specimens that were obtained for investigating physical characteristics. Length and diameter of 100 fibers on each specimen was measured. The tensile strength of 100 fiber bundles were measured. And also the color values of them were measured with spectrocolorimeter. The length of retted kenaf fiber was 16.97cm. Then it decreased to 11.43cm after bleaching. Kenaf fiber bundles could be finer by chemical processes that remove non-cellulosic materials. The thickness of retted fiber was $132{\mu}m$. And after undergoing the chemical processes to remove non-cellulosic materials, the thickness of kenaf fiber became finer as $73{\mu}m$. Tensile strength of the retted kenaf fiber bundles was 11.37Mpa. The retted kenaf fiber lost their strength as 22.6% by bleaching and as 18.3% by treatment for removing lignin. The retted kenaf fiber showed low whiteness as 56.48 of L*value. After bleaching, the kenaf fibers have creamy white color and their whiteness got 90.02 of L*value. After the treatment for removing hemicellulose, the kenaf fibers also have creamy white color and their whiteness got L* value of 79.02.

• Journal of Biosystems Engineering
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• 제29권2호
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• pp.121-130
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• 2004

This study was carried out to develop a miller to produce white embryo rice with functional nutrients by improving the conventional vertical miller. The effects of rice moisture content and the shaft revolution speed of the miller on germ(embryo) adherence rate, whiteness, broken rice rate, and cracked rice rate were investigated. Also, the effect of the mesh size of emery stones on the germ adherence rate was investigated. The vertical prototype miller was improved with the increasement of about 42% in producing white embryo rice at proper conditions(shaft revolution speed of 900 rpm, emery stones of mesh ＃50, processing capacity of 2.3t/h, zero outlet resistance, rice moisture content of 16.2%). The results were as follows: 1. The germ adherence rate of white rice was significantly influenced by the moisture content of brown rice. The germ adherence rate of white rice decreased rapidly with the increase of the moisture content of brown rice. When brown rice with moisture content of 13.2%, 14.5%, 15.2%, 15.4% was milled by the prototype with emery stones of mesh ＃35 and shaft speed of 900(1,100) rpm, rpm adherence rate of milled rice was 76.2%(70%), 69.2%(66%), 45.9(38%), 13.0(9%), respectively. 2. The whiteness of white rice milled by the prototype with emery stones of mesh ＃35 and shaft speed of 1,100(900)rpm increased from 27(23) to about 40, respectively, as the moisture content of brown rice increased from 13.2% to 17.2%. 3. The rate of broken rice of white rice milled at 900rpm decreased by 0.6∼1.0% compared with that at 1,100rpm when the moisture content of brown rice was less than 15.2%. 4. The germ adherence rate was increased by 10.3% and 11.0%, respectively when brown rice with moisture content of 16.2% and 15.5% was milled by the prototype miller with shaft speed of 900rpm and emery stones of mesh ＃50 instead of mesh ＃35. 5. Considering the germ adherence rate, broken rice rate, and whiteness of milled rice, the proper milling conditions of the prototype miller for producing embryo rice were the moisture content of about 15%, the processing capacity of 2.3t/h and minimum outlet resistance of 0Nㆍm with shaft speed of 900rpm and emery stones of mesh ＃50.

• 자원환경지질
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• 제49권5호
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• pp.335-347
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• 2016

정선 지역 고품위 석회석 광산인 강원, 충무 및 백운 광산을 대상으로 풍촌층 상부 층준의 대표적 탄산염암을 구분하고 각 유형의 전암 분석 및 VNIR-SWIR(visible near infrared-short wavelength infrared) 분광분석을 실시하여, 현장에서 고품위 석회석의 CaO 함량, 이질 불순물 및 백색도를 평가할 수 있는 분석법을 제시하였다. 동일 시료에서 분말 시료의 분광 반사도는 절단 시편에 비하여 매우 높은 분광 반사도를 보였고, 탄산염암의 분말 시료는 백색도와 분광 반사도가 0.99의 매우 높은 상관관계를 보이고 있다. 전암 분석에서 확인된 충무광산의 방해석과 백운석 분말 시료를 75:25, 50:50, 25:75 질량비로 혼합하여 각각 스펙트럼의 변화를 확인하고, 탄산염암의 CaO 함량과 흡수파장을 비교한 결과 0.98~0.99로 매우 높은 상관도를 보이고 있다. 탄산염암의 흡수파장과 화학조성은 2340 nm(55.86 wt.%)에서 2320 nm(29.71 wt.%)로 이는 $CO{_3}^{-2}$ 성분과 결합하고 있는 Ca 함량과 이를 치환하는 Mg 성분 함량의 차이에 따라 흡수 위치가 변화되는 것을 의미하며, 현장에서 분광분석을 통한 탄산염광물의 CaO 함량을 정량적으로 적용할 수 있다.

• 펄프종이기술
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• 제47권3호
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• pp.34-39
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• 2015

Fluorescent whitening agents (FWAs) are widely applied in the papermaking process to improve the CIE whiteness and the ISO brightness of papers. Large amounts of FWAs are used in the paper and paperboard industry, but no standard method exists for quantitative FWA analysis. Therefore, a new method is needed to analyze the presence of FWAs in paper and paperboard to control their additions and applications. In particular, FWA analysis must concentrate on those used for surface treatment of paper because their use in surface applications has increased recently. The purposes of this study were to measure the optical properties of papers surface-treated with oxidized starch containing FWAs and to deduce the regression equations for the quantitative analysis of FWAs used for surface treatments. Surface sizing was carried out to treat the surface of a base paper with T-FWA and H-FWA, and the pickup weight of the surface sized paper was measured to determine the real weight of FWAs transferred onto the paper surface. After surface sizing and preconditioning, the paper was evaluated for CIE whiteness, ISO brightness, fluorescence index, and reflectance at 440 nm using an Elrepho spectrophotometer. The CIE whiteness and the ISO brightness increased linearly as FWA content increased. The fluorescence index and the reflectance showed linear relationships with T-FWA and H-FWA. Linear regression equations were determined for the quantitative analysis of FWAs used for surface treatments.

• 한국염색가공학회지
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• 제10권6호
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• pp.1-9
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• 1998

The effects of oxygen plasma treatments at different discharge power, reaction pressure, treatment time on yellowing of polyester fabrics were studied. Surface characteristics of the treated fabrics were also investigated by means of SEM and ESCA. The results were as follows : The yellowing of fabrics increases as the power and the treatment time are increased, and decreases as the pressure is increased. The plasma treatment of 100 Watt, 200 mTorr, 5 min. is the optimal condition which is most effective in holding whiteness as well as high weight loss of fabrics.

• 한국의류학회지
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• 제23권1호
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• pp.14-21
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• 1999

The Tencel fabrics were treated with bio-softness finish to improve softness. The change of the properties depending on the softner as well as cellulase treatment was investigated. The relative activity of cellulase for tencel was maximum ap pH 4-4.3 cellulase concentration 14-16% (o. w .f) treatment time 4 hour and liquor ratio 100: 1 The treatment of epoxy silicon softner improved in pilling whiteness dye absorption of Tencel fabric.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2009년도 학술발표대회
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• pp.213-214
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• 2009

In order to promote an efficiency CPB process, we developed microwave system in CPB process. The whiteness and penetration ability of microwave-CPB pre-treated fabrics were superior to CPB only. This results indicates that microwave-CPB pre-treatment promotes CPB efficiency in agent usages and batching time.