• Title/Summary/Keyword: cracker

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A Study on the Characteristics of Spontaneous Ignition for Rice Cracker (쌀과자의 자연발화 특성에 관한 연구)

  • Kim, Hong;Kang, Young-Goo
    • Journal of the Korean Society of Safety
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    • v.10 no.4
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    • pp.75-80
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    • 1995
  • Spontaneous ignition characteristics of rice cracker were observed by preforming experiments at constant ambient temperature. As the results of the experiments, the critical spontaneous ignition temperature were exponentially decreased with the increase of ambient temperature. Type of combustion of rice cracker are smouldering combustion at low ignition temperature and flame combustion at high temperature. The rice cracker containing pam oil showed lower spontaneous ignition temperature than pure rice cracker because of oxidation heat of pam oil.

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Physico-Chemical Characteristics of Korean Red Ginseng Powder on Pulverizing Methods (분쇄방법에 따른 고려홍삼분말의 이화학적 특성)

  • 이종원;서창훈;장규섭
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.3
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    • pp.363-369
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    • 2003
  • In this study, cell cracker method as a non-collision method was evaluated for the possibility of new red ginseng grinding technique. The moisture contents were 3.16% for the powder pulverized by hammer mill (group A) and 6.30% for the powder produced by cell cracker (group B), and the difference between both groups was significant, The contents of other component such as ash, crude lipid, reducing sugar, total sugar, acidic polysaccharide, crude fiber and crude protein between both groups were not significant. There were no significant differences in phenolic compound, fatty acid, amino acid, free sugar, crude saponin and ginsenosid contents between both groups. And also the contents of mineral components were evaluated to determine the incorporation of red ginseng powder during grinding, and also the differences of those between both groups were not significant.

Se Cracker를 이용하여 제작된 Cu(In,Ga)$Se_2 $ 박막 태양전지의 특성

  • Park, Su-Jeong;Jo, Dae-Hyeong;Kim, Ju-Hui;Jo, Yu-Seok;Yun, Jong-Man;Jeong, Yong-Deok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.427-427
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    • 2012
  • Cu(In,Ga)$Se_2 $ (CIGS) 박막 태양전지는 높은 효율과 낮은 생산 단가로 인해 많은 연구가 이루어지고 있다. 특히, Se flux는 박막의 특성에 가장 중요한 CIGS의 결정성, 결정립 크기, 결정방향을 형성하는데 영향을 주는 것으로 알려져 있다. 일반적인 co-evaporation에 사용되는 Se effusion cell의 경우, 높은 분자가를 가지는 Se 분자들이 공급되기 때문에 낮은 반응성을 보이지만 Se cracker cell을 사용할 경우 Se 분자들이 열적으로 크래킹되어 낮은 분자가를 가지므로 화학적으로 높은 반응성을 가진다. 따라서 적은 양의 Se으로도 양질의 CIGS 박막 제작이 가능하다. 본 연구에서는 Se effusion cell과 cracker cell을 이용하여 CIGS 광흡수층을 제작하였으며, 각각 제작된 CIGS 박막의 특성을 비교하였다. 또한 Se cracker cell의 reservoir zone(R-zone) 온도를 통해 Se flux를 변화시켜 Se flux에 따른 CIGS 박막 태양전지의 특성에 대해 알아보았다. SEM, EDS, XRD 측정을 통해 박막의 특성을 분석하였고, J-V 측정을 통해 태양전지의 특성에 대해 알아보았다. Se cracker를 사용하여 제작된 CIGS 박막의 결정립 크기가 effusion cell로 제작된 박막보다 더 크게 나타났고, Se flux가 증가할수록 결정립의 크기는 증가하였다. Se cracker의 flux가 $0.17{\'{{\AA}}}$/s일 때 반사방지막 없이 13.14%의 효율을 나타내었다.

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Cracker Cell을 이용한 $CuInSe_2$ 박막의 셀렌화 공정 연구

  • Go, Hang-Ju;Kim, Hyo-Jin;Han, Myeong-Su;Kim, Dae-Yeong;Park, Gwang-Hun;Park, Jae-Hyeong;Jo, Yu-Seok;Ha, Jun-Seok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.08a
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    • pp.163-163
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    • 2011
  • 셀레늄(Selenium: Se) cracker cell을 이용하여 셀렌화한 $CuInSe_2$ (CIS)박막에 대해 연구한 결과를 발표하고자 한다. 화석연료의 과도한 사용으로 지구온난화라는 환경문제가 대두되면서 영구적이고 무상의 태양에너지 이용에 대한 필요성이 점차 높아지고 있다. 빛에너지를 전기에너지로 변화시키기 위한 태양전지는 재료에 따라 다양하게 개발되고 있으며 그 중 가장 주목을 받고 있는 것 중의 하나가 $CuInSe_2$을 광흡수층으로 하는 CIS 박막 태양전지이다. CIS 박막은 태양전지의 광흡수층으로 사용되는데 직접천이형 밴드구조를 가지고 있고, 약 $10^5$ $cm^{-1}$의 높은 광흡수계수를 가지고 있어 태양전지 광흡수층으로 적합한 물질로 각광받고 있다. CIS는 에너지 밴드갭이 ~1 eV로 실리콘과 유사한 밴드갭을 가지고 있으나 이는 Ga, Al을 In 대신 치환함으로 조절할 할 수 있다. 무엇보다도 sodalime 유리와 같은 저가의 기판위에 스퍼터와 같은 장치로 대면적 CIS 박막태양전지를 만들 수 있다는 것이 산업적인 면에서 장점으로 알려져 있다. 본 연구에서는 sodalime 유리기판 위에 스퍼터 방법으로 CIS 박막을 증착하고 Se cracker cell로 셀렌화하여 CIS 박막을 제조하는 것을 조사연구 하였다. 스퍼터를 이용하여 유리기판위에 Mo (Molybdenum)을 증착하고 그 위에 Cu-In-Se박막을 증착하였다. Cu-In-Se/Mo/유리기판 시료는 동일 챔버에서 Se cracker cell을 이용하여 셀렌화 처리 하였다. 물성비교를 위하여 Knudson-cell을 이용한 셀렌화도 시행하였다. Se cracker cell은 고체 Se를 가열하는 부분(R-zone)과 Se flux를 cracking 하는 부분(C-zone)으로 나누어져 있으며 C-zone은 700$^{\circ}C$로 고정하였다. 셀렌화 기판 온도는 425$^{\circ}C$로 고정하였고 Se cracker 온도는 330~375$^{\circ}C$까지 변화시켜 가며 CIS 박막을 제조하였다. 제조된 CIS 박막의 물성 조사는 사진, 현미경, SEM, EDX, XRD, Hall effects를 이용하였다. Se cracker cell로 셀렌화한 CIS 박막은 island 구조를 하고 있음을 알 수 있었다. CIS 박막의 island의 크기와 모양은 셀렌화시 R-zone 온도(Cu-In-Se 박막에 조사되는 셀레늄의 량)에 큰 영향을 받았다. 셀렌화시 셀레늄량이 적을 때는 island가 커지며 불균일해지고 셀레늄량이 많을 때 island가 작고 균일해지는 경향을 SEM을 통해 관찰할 수 있었다. X-ray 회절을 통해 셀레늄량이 적을 경우 CIS 결정이외의 결정이 박막내에 형성됨을 알 수 있었다. 학술회의에서 Se cracker cell을 이용한 셀렌화에 관한 보다 깊은 연구결과를 발표하고자 한다.

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Quality Characteristics of Korean Red Ginsneg Powder on Pulverizing Methods (분쇄방법에 따른 고려홍삼분말의 품질특성)

  • Seo, Chang-Hoon;Lee, Jong-Won;Do, Jae-Ho;Chang, Kyu-Seob
    • Journal of Ginseng Research
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    • v.26 no.2
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    • pp.79-84
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    • 2002
  • In this study, cell cracker method as a non-collision method was evaluated for the possibility in manufacturing red ginseng powder. In color value of red ginseng powder, the L values indicating brightness were 68.18 for hammer mill (group A) and 72.08 for cell cracker (group B). The a values (redness) and b values (yellowness) were 4.21 26.56 for group A and 5.73, 28.36 for group B, respectively. As an extraction time increased, the absorbances at 420 nm of water extract of both groups were increased. In the loose bulk density, tapped bulk density and volume reduction radio indication the of powder in group A were less than those in group B. In both groups, the angles of side of red ginseng powder were shown less value than the angles of side of the powder. These two angles in group A were lets than those in group B. In sensory evaluation, the touchness between both groups was, not observed significant difference. In the contrary, the color and flavor, main factors affecting the overall quality of red ginseng powder product of group B were shown superior to those of group A. The overall preference of group B was shown higher than that of group A.

Cracker 황화법에 의한 ZnS 버퍼층의 특성과 Cu(In,Ga)$Se_2$ 박막 태양전지 제작

  • Park, Sang-U;Jo, Dae-Hyeong;Lee, U-Jeong;Wi, Jae-Hyeong;Han, Won-Seok;Jeong, Chi-Seop;Kim, Je-Ha;Jeong, Yong-Deok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.08a
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    • pp.309.1-309.1
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    • 2013
  • 현재까지 CIGS 박막 태양전지는 습식공정인 화학적 용액성장법을 사용하여 형성된 CdS버퍼층을 적용할 경우에 가장 높은 효율을 보이고 있다. 그러나, Cd의 독성 문제와 진공 공정과 호환되지 않는 습식공정 때문에 비독성 건식 공정 버퍼층에 대한 연구가 활발히 진행되고 있다. 습식 공정 CdS 버퍼층을 대체하기 위하여 CdS에 비해 밴드갭이 커서 단파장에서 광 손실이 적은 ZnS 버퍼층을 cracker 황화법을 이용하여 제작하여 CIGS 박막 태양전지에 적용하였다. ZnS 버퍼층을 성장시키기 위해 DC 스퍼터를 사용하여 Zn 박막을 증착한 후, cracker를 사용하여 황화반응을 시켰다. cracker의 cracking zone 온도에 따른 S 반응성을 ZnS 박막의 투과도 변화를 통하여 관찰하였다. 성장된 ZnS 박막은 X-ray diffraction와 Rutherford backscattering spectrometry을 이용하여 박막의 결정성과 조성을 분석하였고, SEM 측정을 통하여 박막의 단면 및 표면 형상을 관찰하였다. 그리고 reflection electron energy loss spectroscopy 분석을 통해 밴드갭을 측정하였다. $700^{\circ}C$의 cracking zone 온도, 3 nm의 Zn 두께, 1 분의 황화공정 조건에서 제작된 ZnS 박막을 CIGS 태양전지의 버퍼층으로 적용한 결과, 반사방지막 없이 12.6%의 변환효율을 얻었다.

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Effect of Concentrations of Wheat Flour and Sugar on Sponge Fermentation of Soda Cracker (밀가루 및 당 농도가 소다크랙커의 스폰지 발효에 미치는 영향)

  • Kim, Sang-Yong;Lee, Byung-Don;Kim, Jung-Min;Oh, Deok-Kun
    • Korean Journal of Food Science and Technology
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    • v.29 no.2
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    • pp.387-389
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    • 1997
  • Effect of concentrations of wheat flour and glucose on the sponge fermentation of soda cracker by the mixed lactic acid bacteria of L. brevis, L. fermentum and L. plantarum was investigated. When glucose was added to the wheat flour solution, pH was higher and TTA (total titrable acid) was lower as compared with the medium without glucose. This results suggested that glucose in the solution stimulate cell growth but inhibit the production of organic acids. With increasing of wheat flour concentration, pH decreased and TTA increased during the sponge fermentation of soda cracker.

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Developing descriptive analysis protocol for gochujang: establishing optimal palate cleanser (고추장 묘사분석을 위한 프로토콜 개발: 입가심물질 중심으로)

  • Lee, Eun-Hye;Chung, Seo-Jin;Yu, Seon-Mi;Han, Kui-Jeong
    • Korean journal of food and cookery science
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    • v.29 no.5
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    • pp.489-500
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    • 2013
  • This study was conducted to establish an effective palate cleanser when conducting descriptive analysis for gochujang products. In addition, descriptive analysis procedure for gochujang products was optimized. A generic descriptive analysis was performed on 4 types of gochujang samples varying in hot and spicy levels. The sensory attributes developed were 9 odors, 13 flavors, 4 texture and mouth feel attributes, and 4 appearance attributes. In order to select an effective palate cleanser for gochujang, 5 types of cleansers were tested (water, water+bread, water+cucumber, water+milk, water+cracker). Correct answering rate, significant numbers of product effect on sensory attributes, and the mean hot and spicy intensity values were considered to select the optimal palate cleanser. Results showed that as the hot & spicy level increased, red pepper odor and flavor significantly increased whereas umami taste intensity decreased. When comparing the efficiencies of various palate cleanser, the correct answer rates were the highest when warm water was used with either cucumber or cracker. Additionally, the attribute intensities were better differentiated between gochujang samples when cracker, white wheat bread, or cucumber were used. Overall, warm water with cucumber or cracker were shown to be the most effective cleansers.

Quality Characteristics of Korean Red Ginseng Powder with Different Milling Methods (분쇄방법에 따른 고려홍삼분말의 품질특성)

  • 서창훈;이종원;도재호;김나미;양재원;장규원
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.3
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    • pp.370-374
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    • 2003
  • Cell cracking method using a non-collision was evaluated for the possibility of new red ginseng grinding technique. Based on particle size distribution analysis by 1size shaker, the ratios of 100 mesh penetrated particles were 94.9% for hammer mill (group A) and 95.6% for cell crack (group B). The ratio of 120 mesh penetrated particle of group A was higher than that in group B. The particle size distributions for 100 mesh non-penetrated Powder between 2 groups were not significantly different, and particle size distribution analysis by laser scattering analyzer showed that the particle size ranges were 0.77~128.07 ${\mu}{\textrm}{m}$ for group A and 4.24~180.07 ${\mu}{\textrm}{m}$ for group B. The Particle size distribution in group A was more broad than that in group B. The mean particle size in group B was larger than that in group A, while the standard deviation of particle size distribution in group B was less than that in group A. Structural surface characteristics, in group A, particle size distribution was broad and the distribution curve was amorphous. The structure of individual particles was similar to unequal stone which was roughly grinded and had soft cotton-like surface. In the contrary, in group B, particle size distribution was relatively narrow and also individual size particles were ubiquitously distributed. The structure of individual particles was unequal cut stone shape.

Interface Analysis of Cu(In,Ga)Se2 and ZnS Formed Using Sulfur Thermal Cracker

  • Cho, Dae-Hyung;Lee, Woo-Jung;Wi, Jae-Hyung;Han, Won Seok;Kim, Tae Gun;Kim, Jeong Won;Chung, Yong-Duck
    • ETRI Journal
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    • v.38 no.2
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    • pp.265-271
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    • 2016
  • We analyzed the interface characteristics of Zn-based thin-film buffer layers formed by a sulfur thermal cracker on a $Cu(In,Ga)Se_2$ (CIGS) light-absorber layer. The analyzed Zn-based thin-film buffer layers are processed by a proposed method comprising two processes - Zn-sputtering and cracker-sulfurization. The processed buffer layers are then suitable to be used in the fabrication of highly efficient CIGS solar cells. Among the various Zn-based film thicknesses, an 8 nm-thick Zn-based film shows the highest power conversion efficiency for a solar cell. The band alignment of the buffer/CIGS was investigated by measuring the band-gap energies and valence band levels across the depth direction. The conduction band difference between the near surface and interface in the buffer layer enables an efficient electron transport across the junction. We found the origin of the energy band structure by observing the chemical states. The fabricated buffer/CIGS layers have a structurally and chemically distinct interface with little elemental inter-diffusion.