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The Effect of Barrel Vibration Intensity to the Plating Thickness Distribution

  • Lee, Jun-Ho;Roselle D. Llido
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 1999년도 추계학술발표회 초록집
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    • pp.15-15
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    • 1999
  • In chip plating, several parameters must be taken into consideration. Current density, solution concentration, pH, solution temperature, components volume, chip and media ratio, barrel geometrical shape were most likely found to have an effect to the process yields. The 3 types of barrels utilized in chip plating industry are the conventional rotating barrel. vibrational barrel (vibarrel), and the centrifugal type. Conventional rotating barrel is a close type and is commonly used. The components inside the barrel are circulated by the barrel's rotation at a horizontal axis. Process yield has known to have higher thickness deviation. The vibrational barrel is an open type which offers a wide exposure to electrolyte resulting to a stable thickness deviation. It rotates in a vertical axis coupled with multi-vibration action to facilitate mixed up and easy transportation of components, The centrifugal barrel has its plated work centrifugally compacted against the cathode ring for superior electrical contact with simultaneous rotary motion. This experiment has determined the effect of barrel vibration intensity to the plating thickness distribution. The procedures carried out in the experiment involved the overall plating process., cleaning, rinse, Nickel plating, Tin-Lead plating. Plating time was adjusted to meet the required specification. All other parameters were maintained constant. Two trials were performed to confirm the consistency of the result. The thickness data of the experiment conducted showed that the average mean value obtained from higher vibrational intensity is nearer to the standard mean. The distribution curve shown has a narrower specification limits and it has a reduced variation around the target value, Generally, intensity control in vi-barrel facilitates mixed up and easy transportation of components, However, it is desirable to maintain an optimum vibration intensity to prevent solution intrusion into the chips' internal electrode. A cathodic reaction can occur in the interface of the external and internal electrode. $2HD{\;}+{\;}e{\;}{\rightarrow}20H{\;}+{\;}H_2$ Hydrogen can penetrate into the body and create pressure which can cause cracks. At high intensity, the chip's motion becomes stronger, its contact between each other is delayed and so plating action is being controlled. However, the strong impact created by its collision can damage the external electrode's structure thereby resulting to bad plating condition. 1 lot of chip was divided into two equal partion. Each portion was loaded to the same barrel one after the other. Nickel plating and tin-lead plating was performed in the same station. Portion A maintained the normal barrel vibration intensity and portion B vibration intensity was increased two steps higher. All other parameters, current, solution condition were maintained constant. Generally, plating method find procedures were carried out in a best way to maintained the best plating condition. After plating, samples were taken out from each portion. molded and polished. Plating thickness was investigated for both. To check consistency of results. 2nd trial was done now using different lot of another characteristics.

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CHARACTERISTICS OF HETEROEPITAXIALLY GROWN $Y_2$O$_3$ FILMS BY r-ICB FOR VLSI

  • Choi, S.C.;Cho, M.H.;Whangbo, S.W.;Kim, M.S.;Whang, C.N.;Kang, S.B.;Lee, S.I.;Lee, M.Y.
    • 한국표면공학회지
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    • 제29권6호
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    • pp.809-815
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    • 1996
  • $Y_2O_3$-based metal-insulator-semiconductor (MIS) structure on p-Si(100) has been studied. Films were prepared by UHV reactive ionized cluster beam deposition (r-ICBD) system. The base pressure of the system was about $1 \times 10^{-9}$ -9/ Torr and the process pressure $2 \times 10^{-5}$ Torr in oxygen ambience. Glancing X-ray diffraction(GXRD) and in-situ reflection high energy electron diffracton(RHEED) analyses were performed to investigate the crystallinity of the films. The results show phase change from amorphous state to crystalline one with increasingqr acceleration voltage and substrate temperature. It is also found that the phase transformation from $Y_2O_3$(111)//Si(100) to $Y_2O_3$(110)//Si(100) in growing directions takes place between $500^{\circ}C$ and $700^{\circ}C$. Especially as acceleration voltage is increased, preferentially oriented crystallinity was increased. Finally under the condition of above substrate temperature $700^{\circ}C$ and acceleration voltage 5kV, the $Y_2O_3$films are found to be grown epitaxially in direction of $Y_2O_3$(1l0)//Si(100) by observation of transmission electron microscope(TEM). Capacitance-voltage and current-voltage measurements were conducted to characterize Al/$Y_2O_3$/Si MIS structure with varying acceleration voltage and substrate temperature. Deposited $Y_2O_3$ films of thickness of nearly 300$\AA$ show that the breakdown field increases to 7~8MV /cm at the same conditon of epitaxial growing. These results also coincide with XPS spectra which indicate better stoichiometric characteristic in the condition of better crystalline one. After oxidation the breakdown field increases to 13MV /cm because the MIS structure contains interface silicon oxide of about 30$\AA$. In this case the dielectric constant of only $Y_2O_3$ layer is found to be $\in$15.6. These results have demonstrated the potential of using yttrium oxide for future VLSI/ULSI gate insulator applications.

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신비탕 및 가미신비탕이 Allergy 천식 모델 흰쥐의 BALF내 면역세포 및 혈청 IgE에 미치는 영향에 관한 연구 (The Effects of Shinbi-tang and Gamishinbi-tang on Immune Cell and Serum OA-specific IgE in BALF in Rat Asthma Model)

  • 김승수;정희재;정승기;이형구
    • 대한한의학회지
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    • 제23권2호
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    • pp.198-210
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    • 2002
  • Background : Asthma is a chronic inflammatory disorder under immunological influence. Shinbi-tang and Gamishinbi-tang are herbal decoctions used for treating asthma in traditional herbal medicine. Objective : To evaluate the effects of Shinbi-tang and Gamishinbi-tang on immune cell & serum OA-specific IgE in broncho-alveolar lavage fluid (BALF) in rat asthma model. Material and Methods : Rats were sensitized with ovalbumin (OA); at day 1 sensitized group and Shinbi-tang and Gamishinbi-tang groups were systemically immunized by subcutaneous injection of 1mg OA and 300mg of Al(OH)$_3$ in a total volume of 2ml. At the same time, 1 ml of 0.9% saline containing 6 x 10$^{9}$ B. pertussis bacilli was injected by i.p. 14 days after the systemic immunization, rats received local immunization by inhaling 0.9% saline aerosol containing 2%(wt/vol) OA. A day after local immunization, HAL fluid was collected from the rats. Rats were orally administered with each of Shinbi-tang and Gamishinbi-tang extract for 14 days from the day after local immunization. Lymphocyte, CD4+ T cell CD8+ T cell counts, CD4+/CD8+ ratio in BALF, change of serum OA-specific IgE level, CD4+ T cell CD8+ T cell percentages in the peripheral blood were measured and evaluated. Results : Shinbi-tang and Gamishinbi-tang showed an alleviating effect on asthmatic responses of rats. Shinbi-tang decreased total cell, lymphocyte, CD4+ T cell in BALF, serum OA-specific IgE level as compared with the control group. Gamishinbi-tang decreased total cell, lymphocyte, CD4+ T cell, and CD4+/CD8+ ratio in HALF as compared with the control group. CD4+/CD8+ ratio in HALF from Shinbi-tang group and serum OA-specific IgE level from Gamishinbi-tang group didn't show any significant variation from control group. CD8+ T cell in HALF, CD3+CD4+ T cell and CD3+CD8+ T cell percentages in peripheral blood showed no significant variation among groups. Conclusion : Shinbi-tang and Gamishinbi-tang alleviated asthmatic hypen-eactivity of the rat immune system through CD4+ T cell and serum IgE. Further the study of immune system modulating mechanism is expected.

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시판 된장을 이용한 식빵 제조: 1. 된장의 이화학적 특성 및 된장을 첨가한 식빵의 물리적 특성 (Development of Yeast Leavened Pan Bread Using Commercial Doenjangs (Korean Soybean Pastes): 1. Physicochemical Properties of Doenjang and Physical Properties of Bread Added with Doenjang)

  • 오현주;문혜경;김창순
    • 한국식품영양과학회지
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    • 제32권7호
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    • pp.1002-1010
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    • 2003
  • 생리활성이 우수하다고 알려진 된장의 소비확대를 위하여 시판 된장을 이스트 발효 식빵 제조에 이용하고자 식빵 배합비에 7종(A; 재래식 된장, B∼E; 시판 개량식 된장, F;시판 Miso type 된장, G; Japanese Miso)의 동결건조한 된장분말을 2.5∼10.0% 첨가하여 발효력과 오븐팽창력을 관찰하고 빵품질을 물리적 측면에서 조사하였다. 사용된 시판된장 7종의 이화학적 특성치로는 일반성분을 비롯하여 아미노태질소, 총산도, 환원당, 유리당, 염도, 유기산 함량 및 단백질분산지수(PDI)를 제시하였다. 빵 배합비에 된장분말 5.0% 이하의 첨가는 오븐팽창력의 현저한 증가로 모든 된장 첨가식빵 부피가 증가하여 무첨가구에 비하여 최대 13%까지 높게 나타났다. 또한 된장첨가로 기계적 조직감 측정치인 경도(hardness), 검성 (gumminess), 씹힘성(chewiness) 등이 감소하여 전반적으로 부드러워졌고, 빵의 색은 어두워졌다. 그러므로 식빵제조에 시판된장의 사용은 빵의 물리적 품질 향상에 매우 긍정적인 효과를 가져왔다. 이때 식빵의 부피나 조직감은 된장 종류나 첨가수준에 의하여 독립적으로 영향을 받을 뿐만 아니라 이들 처리조합의 상호작용에 의하여도 크게 영향을 받는 것으로 나타났다.

일부 시판 즙장의 품질 특성 및 항산화 활성 (Quality Characteristics and Antioxidant Activities of Commercial Jeupjang)

  • 김하윤;황인국;유선미;황영;차성미;김행란
    • 한국지역사회생활과학회지
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    • 제21권4호
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    • pp.571-579
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    • 2010
  • Jeupjang has long been considered only a local delicacy. So, it has gradually been forgotten because its name and definition have not been established. This study was performed in order to provide some basic data by comparing the general components, color, free amino acids, free sugar, organic acids and antioxidant activities between commercial Jeupjang(GG, GD, JM, NJ, NS). Moisture contents, crude protein, crude fat and crude ash contents of Jeupjang were 48.07~61.77%, 4.08~10.53%, 3.92~4.64%, and 3.63~9.95%. pH, titrable acidity and salt in Jeupjang were 4.32~5.50, 9.37~14.82 mL(1N-NaOHmL), and 3.27~8.90%. Amino-type nitrogen content is 42.05~ 138.83mg%. Lightness(L), redness(a) and yellowness(b) values in color of Jeupjang were10.04~21.89, 18.92~28.80, and 17.16~37.56. The total content of free amino acids in commercial Jeupjang ranged from 35.22mg% to 306.02mg% in which it showed wide variation among samples. The major free amino acids were glutamic acid, aspartic acid, alanine and proline. The major free sugars were fructose(0.31~1.60%), glucose(6.20~ 13.61%) and maltose(7.34~10.01%). The major organic acids were succinic acid(29.08~ 103.62 mg%) and citric acid(3.08~108.69 mg%). Total polyphenol contents were from 1.16 mg/g to 1.78 mg/g, DPPH radical scavenging activity is from 0.57 AEAC to 1.53 AEAC and ABTS radical scavenging activity is from 1.58 AEAC to 2.85 AEAC. This result might cause the differences of soybean composition, processing methods and brewing periods. For the succession of traditional fermented food such as Jeupjang, quality standards are required. To this end, the standardization of manufacturing processes must be followed.

Stress-Governed Expression and Purification of Human Type II Hexokinase in Escherichia coli

  • Jeong, Eun-Ju;Park, Kyoung-Sook;Yi, So-Yeon;Kang, Hyo-Jin;Chung, Sang-J.;Lee, Chang-Soo;Chung, Jin-Woong;Seol, Dai-Wu;Chung, Bong-Hyun;Kim, Moon-Il
    • Journal of Microbiology and Biotechnology
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    • 제17권4호
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    • pp.638-643
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    • 2007
  • The full encoding sequence for human type II hexokinase (HXK II) was cloned into the E. coli expression vector pET 21b and expressed as a C-terminally hexahistidine-tagged protein in the BL2l (DE3) strain. The IPTG-induced HXK II approximately accounted for 17% of the total E. coli proteins, and 81% of HXK $II_{6{\times}His}$ existed in inclusion bodies. To improve the production of soluble recombinant HXK II protein, in the functionally active form, we used low temperature, and the osmotic stress expression method. When expressed at $18^{\circ}C$, about 83% of HXK $II_{6{\times}His}$ existed in the soluble fraction, which amounted to a 4.1-fold yield over that expressed at $37^{\circ}C$. The soluble form of HXK $II_{6{\times}His}$ was also highly produced in the presence of 1M sorbitol under the standard condition $(37^{\circ}C)$, which indicated that temperature downshift and low water potentials were required to improve the yield of active recombinant HXK II protein. The expressed protein was purified by metal chelate affinity chromatography performed in an IDA Excellose column charged with $Ni^{2+}$ ions, resulting in about 40mg recombinant HXK II protein obtained with purity over 89% from 51 of E. coli culture. The identity of HXK $II_{6{\times}His}$ was confirmed by Western blotting analysis. Taken together, using the stress-governed expression described in this study, human active HXK II can be purified in sufficient amounts for biochemical and biomedical studies.

Lactobacillus casei Secreting ${\alpha}$-MSH Induces the Therapeutic Effect on DSS-Induced Acute Colitis in Balb/c Mice

  • Yoon, Sun-Woo;Lee, Chul-Ho;Kim, Jeong-Yoon;Kim, Jie-Youn;Sung, Moon-Hee;Poo, Har-Young
    • Journal of Microbiology and Biotechnology
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    • 제18권12호
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    • pp.1975-1983
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    • 2008
  • The neuropeptide ${\alpha}$-melanocyte-stimulating hormone (${\alpha}$-MSH) has anti-inflammatory property by down regulating the expressions of proinflammatory cytokines. Because ${\alpha}$-MSH elicits the anti-inflammatory effect in various inflammatory disease models, we examined the therapeutic effect of oral administration of recombinant Lactobacillus casei, which secretes ${\alpha}$-MSH (L. casei-${\alpha}$-MSH), on dextran sulfate sodium (DSS)-induced colitis in Balb/c mice. Thus, we constructed the ${\alpha}$-MSH-secreting Lactobacillus casei by the basic plasmid, pLUAT-ss, which was composed of a PldhUTLS promoter and ${\alpha}$-amylase signal sequence from Streptococcus bovis strain. Acute colitis was induced by oral administration of 5% DSS in drinking water for 7 days. To investigate the effect of L. casei-${\alpha}$-MSH on the colitis, L. casei or L. casei-${\alpha}$-MSH was orally administered for 7 days and their effects on body weight, mortality rate, cytokine production, and tissue myeloperoxidase (MPO) activity were observed. Administration of L. casei-${\alpha}$-MSH reduced the symptom of acute colitis as assessed by body weight loss (DSS alone: $14.45{\pm}0.2\;g$; L. casei-${\alpha}$-MSH: $18.2{\pm}0.12\;g$), colitis score (DSS alone: $3.6{\pm}0.4$; L. casei-${\alpha}$-MSH: $1.4{\pm}0.6$), MPO activity (DSS alone: $42.7{\pm}4.5\;U/g$; L. casei-${\alpha}$-MSH: $10.25{\pm}0.5\;U/g$), survival rate, and histological damage compared with the DSS alone mice. L. casei-${\alpha}$-MSH-administered entire colon showed reduced in vitro production of proinflammatory cytokines and $NF-{\kappa}B$ activation. The ${\alpha}$-MSH-secreting recombinant L. casei showed significant anti-inflammatory effects in the murine model of acute colitis and suggests a potential therapeutic role for this agent in clinical inflammatory bowel diseases.

Proteomics를 이용한 콩의 발아 전 침종처리에 따른 단백질 발현 양상 비교 분석 (Characterization of Protein Function and Differential Protein Expression in Soybean under Soaking Condition)

  • 조성우;김태선;권수정;;이철원;김홍식;우선희
    • 한국작물학회지
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    • 제60권1호
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    • pp.114-122
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    • 2015
  • 침종 기간과 침종 후 발아의 유무에 따른 단백질 발현을 이차원전기영동을 이용하여 단백질 발현양상을 확인하고 비교 분석한 결과, 침종 기간과 침종 후 발아의 유무에 따른 단백질 발현 양상은 전반적으로 매우 유사하였으며, 주요 단백질의 발현에는 차이가 없었다. 침종 기간에 따른 품종별 단백질 발현 양상은 침종 기간이 길어짐에 따라 단백질 발현정도가 점차 증가되는 것을 확인할 수 있었다. 공시품종들 중 황금콩, 단엽콩, Peking이 다른 품종들에 비하여 침종 4일후에 단백질 발현정도가 급격히 증가하는 것을 알 수 있었다. 침종 후 발아 유무에 따른 단백질 발현양상은 소수의 단백질 spot들을 제외하고는 전반적으로 모든 공시 품종들에서 발아한 종자에서의 단백질 발현정도는 미발아 종자에서보다 높게 확인되었다.

인돌이 인체 전립선암세포 PC3 Cell 전이 관련 Matrix Metalloproteinases (MMPs) 활성과 발현에 미치는 영향 (Effect of Indole-3-Carbinol on Inhibition of MMP Activity via MAPK Signaling Pathway in Human Prostate Cancer Cell Line, PC3 Cells)

  • 김성옥
    • Journal of Nutrition and Health
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    • 제41권3호
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    • pp.224-231
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    • 2008
  • 본 연구는 십자화과 채소의 섭취로 체내유용 물질인 인돌이 전립선암 세포 PC3 cell의 항전이 효과 기전에 미치는 영향에 대하여 알아보았다. 인돌은 전립선암 세포중식을 농도 의존적으로 억제하였으며 인돌에 의한 세포 사멸의 영향과 관계없이 MMP-2, -9의 활성과 전사수준 및 단백질 발현을 억제하였다. 역으로 MMP활성 억제 물질인 TIMP-1,-2의 발현이 인돌 첨가에 의해 증가하였다. $NF{-\kappa}B$의 upstream에 존재하는 MAPK signaling 유전자인 ERK1/2, p38, JNK 발현이 인돌처리로 인산화를 억제하였다. 그리고 전립선암 세포 PC3 침윤성이 인돌 처리 시 유의적으로 감소하였다. 결론적으로 인돌은 PC3 인체 전립선암 세포의 전이 과정을 MAPK phthway를 통한 MMP 활성과 발현 억제, TIMP 발현 증가로 암 세포 전이 억제를 하는 것 으로 나타나 암 전이 억제 식품으로 가능성을 제시한다.

한국 학생들의 영어 철자 인지와 발화에 대한 훈련효과 (Training Effect on the Perception and Production of English Grapheme by Korean Learners of English)

  • 초미희
    • 한국콘텐츠학회논문지
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    • 제19권11호
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    • pp.226-233
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    • 2019
  • 다섯 가지 미국 영어 모음 [ʌ, ju, ʊ, u, ə]으로 실현되는 영어 철자 를 어떻게 듣고 발음하는지 그리고 훈련의 효과는 어떠한지 살펴보기 위해서 31명의 한국 대학생들을 대상으로 철자 를 포함한 24개의 영어 단어들에 대하여 사전 시험-훈련-사후 시험의 형태로 인지와 발화 시험을 실시하였다. 전체적 결과를 살펴보면, 사후 시험에서 인지와 발화 점수가 모두 사전 시험보다 유의하게 향상되었으나 다섯 가지 모음 소리가 모두 향상된 것은 아니었다. 인지에서는 긴장 모음 [u]와 이완 모음 [ʊ]을 제외한 모음 소리들의 점수가 유의하게 상승되어서 훈련의 효과를 보였으며 발화에서는 [ʌ], [u], [ʊ]를 제외한 모음들이 훈련의 효과를 보였다. 이는 인지와 발화에서 모두 한국 학생들이 영어의 긴장 모음과 이완 모음의 차이를 구별하기 어려워 한다는 것을 보여주고 있다. 특히 발화에서 이완 모음 [ʊ]를 한국어 [우]와 가장 비슷한 음향적 성질을 가진 긴장 모음 [u]로 대치하여 발음하는 오류를 우세하게 보였으며 [ʌ]의 경우에는 [u]-비슷한 소리들로 대치함으로써 철자의 영향을 실증적으로 보여주었다. 또한 인지와 발화 시험의 오류 유형을 통해서 목표 모음이 [t, d, n, s]같은 혀끝소리 뒤에서는 미국 영어에서 [j]-탈락이 일어난다는 것을 한국 학생들이 모르고 [j] 삽입하는 경우가 기회 수준이상으로 발생하였다. 반대로, 입술소리 ([p, b, f, v, m])나 연구개소리 ([k, g]) 뒤에서는 [j] 소리가 있지만 철자에는 구현되지 않아서 [j]를 탈락시키는 오류도 보였다. 본 연구의 발견점들을 바탕으로 교실 현장에서 학생들에게 지도해야 할 교육적인 함축점도 논의하였다.