• 분석과학
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• 제32권5호
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• pp.196-209
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• 2019

As a traditional method to apply fingerprint powder, brush method ("dusting") can create a risk to the health of crime scene investigators due to the inhalation toxicity of harmful and fine powders. Therefore, as a new method of applying powders, we tried to evaluate the potential of a chamber method for the development of latent fingerprint using fans in a closed chamber with a fixed capacity that can prevent the powders from being blown outside and exposed to the users, by comparing with the development results of the conventional brush method. Fingerprints on glass and plastic (PET) were extracted with black powder and green fluorescent powder, and the sharpness and minutiae of the developed fingerprints were compared for each method. The results of the black powder showed similar results, but the effect of the chamber method was slightly decreased when the green fluorescent powder was used. In order to improve the development with the green fluorescent powder, the mixture (50 : 50) of the fluorescent powder with the silica gel was tested and the results were similar to those of the brush method. It is expected that the chamber method has a high potential as a new powder application method considering the health of the crime scene investigator after fine tuning of development conditions with additional studies.

• 한국식품영양과학회지
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• 제37권2호
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• pp.162-169
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• 2008

처리조건을 달리한 생마늘, 증숙마늘 및 흑마늘 분말을 3% 농도로 고지혈증 유발 흰쥐에 급이하였을 때 혈액 및 간장의 지질함량 변화에 미치는 영향을 비교하였다. 마늘 분말 급이군에서 대조군에 비해 체중 및 식이효율에서 유의적인 차이는 없었다. 간장의 무게는 생마늘 분말 급이군에서 유의적으로 감소되었다. 혈당은 생마늘 분말과 흑마늘 분말첨가 급이시 대조군에 비해 유의적으로 감소되었다. 혈중 총 지질은 흑마늘 분말 급이군에서 가장 낮았으며, 총 콜레스테롤 및 중성지방도 마늘 분말 급이군들에서 유의적인 감소를 보였다. 마늘 분말을 급이함으로써 대조군에 비해 HDL-콜레스테롤의 농도는 증가되었고, LDL- 및 VLDL-콜레스테롤의 농도는 유의적으로 감소되었다. GOT 활성은 증숙마늘 급이군에서 가장 낮았다. 간장조직의 지질 함량은 마늘 분말 급이군에서 유의적으로 낮았다. 간장 조직의 TBARS 함량은 마늘 급이 유무에 따른 유의차가 없었으나, 항산화 활성은 대조군에 비해 마늘 급이군에서 증가되었다. 고지방식이에 3%의 생마늘 및 흑마늘 분말 첨가식이는 혈액 및 간장의 지질 함량 저하에 효과가 있었으며, 특히 흑마늘의 경우 동맥경화 예방 및 체내 지질 개선 효과가 클 것으로 기대된다.

• 대한화장품학회지
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• 제30권2호
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• pp.189-195
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• 2004

카본 블랙은 매우 낮은 밀도로 화장품에는 사용되지 않고 있지만 독성이 없고 안정한 물리적 특성과 검은색의 특성으로 이용 가치가 있다고 사료되는 바이다. 본 연구에서는 TEOS, a) PEO/ lecithin, b) PEO/polyethylene glycol, c) lecithin/polyethylene을 ethanol/water 수용액상에서 계면활성제를 탄화시켜 sol-gei반응에 의해 meso-porous silica샘플을 얻었고 N2 조건하 50$0^{\circ}C$에서 열처리된 organic-inorganic hybrid silica를 합성하였다. Pore안에 카본 블랙을 함유하는 meso-porous silica는 친수성, 소수성 용매에서 모두 좋은 분산성을 보여준다. 이 샘플은 BET에 의해 specific surface area (750$m^2$/g)과 pore size (4-6 nm)이고, XRD측정으로 pore structure (cylindrical type)를, 샘플의 SEM촬영으로 morphology(0.1-0.5$\mu\textrm{m}$ 입자 크기를 갖는 spherical powder)를 갖는다는 것을 알아냈다. 이렇게 합성한 카본-실리카 블랙 컬러를 마스카라에 적용하면 일반적으로 마스카라에 사용되던 블랙 컬러 사용시 보다 좀더 검은색을 보여주는 것은 물론이고 우수한 분산성도 갖는다. 무엇보다 이 파우더의 밀도 조절이 가능하여 마스카라 뿐 만 아니라 모든 화장품에의 사용이 가능하다.

• Journal of Nutrition and Health
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• 제38권8호
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• pp.613-625
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• 2005

This study was designed to evaluate impact of kinds of dietary grain and dietary lipid level on the glucose metabolism and antithrombogenic capacity in obesity induced rats. Total of 80 Sprague-Dawley male rats were raised for one month with control diet containing $50\%$ (w/w) well-milled rice powder and $20\%$(w/w) of dietary lipids. The rats were blocked into 8 groups and raised for two months with diets containing well-milled rice, brown rice, black rice, or glutinous barley powder and 8 or $20\%$(w/w) of dietary lipids. The contents of total dietary fiber in experimental grains were in following order; glutinous barley > black rice > brown rice > well-milled rice. Weekly food intake were lower in glutinous barley group among all experimental groups. Body weight gain was high in high level of fat groups ($50\%$w/w) than medium level of fat groups ($8\%$ w/w). Plasma glucose concentration was not different significantly in each groups. But brown rice group was a little lower than others. Plasma insulin concentration was lower in black rice and glutinous barley group than rice group. Plasma glucagon concentration did not differ significantly among all experimental groups. Hexokinase activities in skeletal muscle are different significantly according to level of dietary fat and grain variety factors. Brown rice group was significantly highest among all experimental groups in hexokinase activity. Plasma $TXB_2$ concentrations in black rice and glutinous barley groups were lower as compared to rice and brown rice groups. Plasma 6-keto-$PGF_{1\alpha}$ concentrations in glutinous barley group was higher as compared to others. In conclusion brown rice has a little lowering effect glucose concentration. Black rice and glutinous barley intakes enhance antithromboenic capacity. It is suggested that the intakes of mixed gains are recommend.

• 한국수소및신에너지학회논문집
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• 제35권3호
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• pp.336-344
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• 2024

In this study, a Ni_0.9Co_0.05Mn_0.05(OH)₂ precursor used as an anode active material using a black powder leaching solution of a recycled lithium ion battery was prepared through coprecipitation synthesis with co-precipitation time, NH₄OH concentration, pH, and stirring time as variables. The characteristics of the prepared powder were analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM), particle size analysis (PSA), and inductively coupled plasma optical emission spectroscopy (ICP-OES). It was confirmed that the single crystal thickness of the LiNi_1-x-yCo_xMn_yO₂ (NCM) precursor changes depending on the NH₄OH concentration and reaction pH value, and thicker single crystals are formed at 2 M NH₄OH compared to 1 M and at pH 10.8-11.8 compared to pH 11.8-12.0. NCM precursor particles increased with coprecipitation time, and it was confirmed that the 72 hours NCM precursor had the largest particle size. Through ICP-OES analysis, it was confirmed that the NCM precursor was synthesized with the target composition of Ni²⁺:Co²⁺:Mn²⁺=90:5:5.

• 한국분말재료학회지
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• 제1권2호
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• pp.135-144
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• 1994

Silicon carbide powder was prepared from mixtures of Sangdong silica sand and carbon black by SHS (Self propagating High temperature Synthesis) method which utilizes magnesiothermic reduction of silica. In the powder preparation process, the reacted powder was leached by chloric acid to remove the magnesium oxide and was subsequently roasted to remove free carbon. The impurities were mostly eliminated by hot acid treatment. The resultant SiC powder showed the mean particle size of 0.22 ${\mu}{\textrm}{m}$ and the specific surface area of $66.55 m^2/g$. The SiC powder was mixed with 1 wt% of boron and of carbon to increase densification rate. The mixed powder was pressed and sintered pressurelessly at $2100^{\circ}C$ for 30 min in argon gas. The sintered body showed the hardness of $2550 kg{\cdot}f/mm^2$ and the fracture toughness, KIC of $3.47 MN/m^{3/2}$.

• 한국식품영양과학회지
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• 제34권6호
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• pp.869-874
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• 2005

녹차 및 발효정도에 따른 약발효차, 중발효차, 홍차 가루를 첨가하여 제조한 식빵의 일반성분, 수분결합력, 무게, 부피, 색도, texture 및 관능검사 측정한 결과는 다음과 같다. 차가루 첨가식빵의 수분함량은 $36.02\~36.44\%$로 대조구 $36.98\%$와 거의 차이가 없었다. 조단백질과 회분 함량은 대조구보다 차첨가구가 높게 나타났다 수분결합력은 녹차 첨가구가 가장 높았고, 발효차 첨가구, 대조구 순으로 높게 나타났다 식빵의 부피와 비용적은 대조구가 가장 높게 나타났고, 발효 차 첨가구, 녹차첨가구 순으로 높게 나타났다. 색도는 대조구에 비하여 발효가 많이 진행된 차가루를 첨가한 식빵일수록 L값은 낮고, a값과 b값은 높게 나타났다. 식빵의 견고성은 발효가 많이 진행된 차가루 첨가구일수록 높게 나타난 반면, 응집성은 발효가 많이 진행된 차가루를 첨가할수록 낮게 나타났다 접착성과 씹힘성은 홍차가루 첨가식빵이 가장 높았다. 관능검사 결과, 색깔, 외관, 질감은 대조구가 가장 높은 기호도를 보였고, 향미와 맛은 녹차 및 약발효차 가루 첨가구의 기호도가 높았으며, 전체적인 기호도는 약발효차 가루 첨가구의 선호도가 가장 높게 나타났다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.442-443
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• 2006

Vacuum carbonization of nanometer tungsten powder was investigated in a simple designed apparatus. An X-Y recorder was used to plot differential thermal analysis (DTA) curves to determine starting temperature of carbonization of four samples with different specific surface area. The product was detected by X-ray Diffraction (XRD) and small angle X-ray scattering (SAXS). The results show that finer tungsten powder has lower starting temperature of carbonization. Tungsten powder, which BET surface area is $32.97m^2/g$, is completely carbonized to tungsten carbide at $1050^{\circ}C$, although the starting temperature is $865^{\circ}C$. Particle grows sharply before carbonization.

• 한국분말재료학회지
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• 제25권3호
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• pp.240-245
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• 2018

This study focuses on the fabrication of a WC/Co composite powder from the oxide of WC/Co hardmetal scrap using solid carbon in a hydrogen gas atmosphere for the recycling of WC/Co hardmetal. Mixed powders are manufactured by mechanically milling the oxide powder of WC-13 wt% Co hardmetal scrap and carbon black with varying powder/ball weight ratios. The oxide powder of WC-13 wt% Co hardmetal scrap consists of $WO_3$ and $CoWO_4$. The mixed powder mechanically milled at a lower powder/ball weight ratio (high mechanical milling energy) has a more rapid carbothermal reduction reaction in the formation of WC and Co phases compared with that mechanically milled at a higher powder/ball weight ratio (lower mechanical milling energy). The WC/Co composite powder is fabricated at $900^{\circ}C$ for 6 h from the oxide of WC/Co hardmetal scrap using solid carbon in a hydrogen gas atmosphere. The fabricated WC/Co composite powder has a particle size of approximately $0.25-0.5{\mu}m$.

• 한국식품과학회지
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• 제45권6호
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• pp.735-741
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• 2013

본 연구에 사용된 비열 플라즈마 처리는 양배추와 상추에 접종된 S. Typhimurium, 후춧가루에 존재하는 호기성 미생물, 그리고 고춧가루에 접종된 B. cereus 영양 세포를 효과적으로 저해시켰으나, 고춧가루에 존재하는 호기성균과 B. cereus 포자는 효과적으로 저해시키지 못했다. 양배추에 접종된 S. Typhimurium를 가장 많이 저해시키는 최적 조건은 746 W, 6.8분으로 예측되었고, 이 때 저해 정도는 1.9 log $CFU/cm^2$로 예측되었다. Fermi 모델과 Weibull 모델이 플라즈마 처리를 이용한 양배추에 접종된 S. Typhimurium 저해를 설명하는데 매우 적합하였다. 본 연구의 결과는 비열 플라즈마 처리를 채소류와 분말 식품의 미생물 안전성을 증진시키는 살균 처리 기술로 발전시키는데 유용할 것으로 사료된다.