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Relationship Between pH and Temperature of Electroless Nickel Plating Solution

  • Nguyen, Van Phuong;Kim, Dong-Hyun
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2018년도 춘계학술대회 논문집
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    • pp.33.1-33.1
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    • 2018
  • pH is expressed mathematically as $pH=-{\log}[H^+]$, is a measure of the hydrogen ion concentration, [$H^+$] to specify the acidity or basicity of an aqueous solution. The pH scale usually ranges from 0 to 14. Every aqueous solution can be measured to determine its pH value. The pH values below 7.0 express the acidity, above 7.0 are alkalinity and pH 7.0 is a neutral solution. The solution pH can be determined by indicator or by measurement using pH sensor, which measuring the voltage generated between a glass electrode and a reference electrode according to the Nernst Equation. The pH value of solutions depends on the temperature and the activity of contained ions. In nickel electroless plating process, the controlled pH value in some limited ranges are extremely important to achieve optimal deposition rate, phosphorus content as well as solution stability. Basically, nickel electroless plating solution contains of $Ni^{2+}ions$, reducing agent, buffer and complexing agents. The plating processes are normally carried out at $82-92^{\circ}C$. However, the change of its pH values with temperatures does not follow any rule. Thus, the purpose of study is to understand the relationship between pH and temperature of some based solutions and electroless nickel plating solutions. The change of pH with changing temperatures is explained by view of the thermal dynamic and the practical measurements.

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Antioxidant Enzymes of Strains Panax ginseng C.A. Mey. and Panax quinquefolius L.

  • Slepyan L.I.;Kirillova N.V;Strelkova M.A.
    • 고려인삼학회:학술대회논문집
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    • 고려인삼학회 2002년도 학술대회지
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    • pp.502-508
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    • 2002
  • The strains of Panax ginseng C.A. Mey., P. quinquefolius L. and selected strains P. ginseng-B, P.ginseng-A, P. quinquefolius-C were investigated. Activities of SOD, catalase and peroxydase were determined by methods of Fridovich et al. (1979), Komov et al.(1975), Bovaird et al.(1982) respectively. Activities of SOD, catalase, peroxydase were investigated every day 5 in cycle of cultivation. For P. ginseng it was the 35 days, P. quinquefolius the 70 days, P. quinquefolius-C 90 days. P. ginseng-B 90 days, P. ginseng-A 60 days. The P. quinquefolius, P. quinquefolius-C, P. ginseng-B had clear differentiation and developed tracheid elements, which are absent in strain of P. ginseng. The peaks of protein content for P. ginseng (4.5 units/g) and for P. quinquefolius (3.5 units/g) were on day 10 and remained unchanged till the last cultivation. The strain P. ginseng-A had two peaks of protein content (2.5 mg/g) on day 15 and on day 30. For P. ginseng-B strain these peaks were on day 5 and day 40 (3.5 mg/g). Peroxydase activity peak (60 units/g) in P. ginseng strain was on day 10. This activity in P. ginseng-B had two peaks on day 15 and day 35 and reached 95 units/g , increasing to 150 units/g to day 80. In strain of P. ginseng-A was only one maximum of this activity -130 units/g on day 45. In P. quinquefolius peroxydase activity was 103 units/g on day 40, increasing to 135 units/g to day 90. For P. quinquefolius-C this activity peak was 136 units/g on day 60. Peroxydase activities for the upper and lower layers of biomass was different and varied considerably from 28-35 units/g in lower to 270-290 units/g for upper layer. The SOD activity had two peaks in P. ginseng strain the 80 units/g and the 70 units/g on day 20 and day 35 respectively. Activity of SOD in P. quinquefolius strain reached 53 units/g on day 40 and increased up to 83 units/g to day 60.The similar increase of SOD activity was marked for P. ginseng-B to 85 units/g on day 90. In P. ginseng strain the 6 molecular isoforms SOD was defined. One of them with RfO,6 was determined in all days of cycle, three other (Rf-0.43; 0.54;0.80) only on day 10 and day 20. The isoform of SOD with Rf-0,29 was detected only on day 10 and with Rf-0,35 only on day 35. The catalase activity decreased in all strains to the last days of cultivation. The changes of SOD, catalase and peroxydase activities reflect the differences between the strains of Panax ginseng and Panax quinquefolius and their selected forms. The correlation between maximum life span of strains and activities of their antioxydant enzymes were detected.

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간호사의 이직의도, 눈치, 직무스트레스가 조직사회화에 미치는 영향 (The Effects of Nurses' Turnover Intention, Nunchi, and Job Stress on Organizational Socialization)

  • 박미라;방설영;제남주
    • 디지털융복합연구
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    • 제18권1호
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    • pp.159-168
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    • 2020
  • 본 연구는 간호사의 이직의도, 눈치, 직무스트레스가 조직사회화에 미치는 영향을 확인하기 위해 시행되었다. G도에 소재한 병원 근무간호사 180명을 대상으로 자료수집 하였다. IBM SPSS WIN/21.0을 이용하여 t-test, ANOVA, Pearson correlation coefficient, Multiple regression을 사용하였다. 조직사회화는 이직의도(r=-.52, p<.001), 직무스트레스(r=-.31, p<.001)와 역상관관계가 있으며, 눈치와 순상관관계가 있었다(r=.33, p<.001). 대상자의 조직사회화에 가장 영향을 미치는 요인은 이직의도(β=-.37, p<.001)이었고, 눈치(β=.26, p<.001), 직무스트레스(β=-.24, p<.001), 원했던 부서로의 배치 여부(β=.19, p=.001), 30세 이하의 연령(β=-.14, p=.012), 수술실 근무(β=.11, p=.050) 순이며, 설명력은 47.0%이었다(F=25.59, p<.001). 따라서 이직의도와 직무스트레스를 낮추기 위해서는 조직 사회화 향상을 위한 프로그램 마련이 필요하며, 근무부서를 배치할 때 연령과 희망부서를 고려할 필요가 있다.

Nomogram Models for Distinguishing Intraductal Carcinoma of the Prostate From Prostatic Acinar Adenocarcinoma Based on Multiparametric Magnetic Resonance Imaging

  • Ling Yang;Xue-Ming Li;Meng-Ni Zhang;Jin Yao;Bin Song
    • Korean Journal of Radiology
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    • 제24권7호
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    • pp.668-680
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    • 2023
  • Objective: To compare multiparametric magnetic resonance imaging (MRI) features of intraductal carcinoma of the prostate (IDC-P) with those of prostatic acinar adenocarcinoma (PAC) and develop prediction models to distinguish IDC-P from PAC and IDC-P with a high proportion (IDC ≥ 10%, hpIDC-P) from IDC-P with a low proportion (IDC < 10%, lpIDC-P) and PAC. Materials and Methods: One hundred and six patients with hpIDC-P, 105 with lpIDC-P and 168 with PAC, who underwent pretreatment multiparametric MRI between January 2015 and December 2020 were included in this study. Imaging parameters, including invasiveness and metastasis, were evaluated and compared between the PAC and IDC-P groups as well as between the hpIDC-P and lpIDC-P subgroups. Nomograms for distinguishing IDC-P from PAC, and hpIDC-P from lpIDC-P and PAC, were made using multivariable logistic regression analysis. The discrimination performance of the models was assessed using the receiver operating characteristic area under the curve (ROC-AUC) in the sample, where the models were derived from without an independent validation sample. Results: The tumor diameter was larger and invasive and metastatic features were more common in the IDC-P than in the PAC group (P < 0.001). The distribution of extraprostatic extension (EPE) and pelvic lymphadenopathy was even greater, and the apparent diffusion coefficient (ADC) ratio was lower in the hpIDC-P than in the lpIDC-P group (P < 0.05). The ROC-AUCs of the stepwise models based solely on imaging features for distinguishing IDC-P from PAC and hpIDC-P from lpIDC-P and PAC were 0.797 (95% confidence interval, 0.750-0.843) and 0.777 (0.727-0.827), respectively. Conclusion: IDC-P was more likely to be larger, more invasive, and more metastatic, with obviously restricted diffusion. EPE, pelvic lymphadenopathy, and a lower ADC ratio were more likely to occur in hpIDC-P, and were also the most useful variables in both nomograms for predicting IDC-P and hpIDC-P.

ITS2 부위의 염기서열 및 RAPC-PCR에 의한 Pseudo-nitzschia 4종의 유연관계 (Phylogenetic Relationships Using ITS2 Sequence and RAPD-PCR Data from Four Species of Korean Pseudo-nitzschia (Bacillariophyceae))

  • Cho, Eun-Seob;Lee, Young-Sik
    • 생명과학회지
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    • 제14권1호
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    • pp.32-37
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    • 2004
  • ITS2 부위를 시퀀싱하여 Pseudo-nitzschia delcatissima, P. multiseries, P. pungens, P. subfraudulenta 상호간의 유전자 다양도를 조사함과 아울러 RAPD-PCR pattern을 이용하여 유사도를 구하였다. 유전자 거리를 근거로 했을 때 P. delicatissima 종은 P. multiseries와 P. pungens와는 유전적 거리가 상당히 요원하였고, 심지어 P. subfraudenlta와도 거리를 보였다. 유사도의 경 P. multiseries와 P. pungens는 0.31로 보인 반면에, P delicatissima는 다른 세종과 0.81를 나타내었다. 따라서 P. delicatissima 종은 P. multiseries, P. pungens, P. subfraudulenta와는 유전적으로 밀접하지 않는 관계로 보였다. ITS2부위는 Pseudo-nitzschia 동정에 사용될 수 있는 유용한 도구로 보이며 형태적으로 구분할 수 없는 P. multiseries와 P. pungens을 구분할 수 있다. 또한 RAPD-PCR 방법도 단시간에 Pseudo-nitzchia을 분리시키는데 사용될 것으로 보인다.

pH 나노센서로의 응용을 위한 UV-가교 P4VP 박막에 고정한 금 나노입자의 특성 (Application of AuNPs immobilized on UV Cross-linked P4VP Thin Film as pH Nanosensors)

  • 김민성;정연태
    • 한국전기전자재료학회논문지
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    • 제21권11호
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    • pp.1010-1018
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    • 2008
  • In this report, we describe the use of gold nanoparticles (AuNPs) immobilized on pH. responsive, cross-linked poly(4-vinylpyridine) (P4VP) thin films, as a potential application for pH nanosensors. The methodology is based on the variation in surface plasmon resonance of immobilized AuNPs with changing the interparticle distances, caused by the swelling/deswelling of the pH responsive P4VP polymer films. The change in optical properties of the immobilized AuNPs in response to the pH of surrounding media was investigated by a simple yet powerful tool; UV-vis absorption spectroscopy. The swelling of the P4VP chains at pH 2 causes an increase in the interparticle distances of immobilized AUNPS ($\sim20nm$) and hence leads to a blue shift of 48 nm in their surface plasmon resonance band peak. On the other hand, when the surrounding media was altered from pH 2 to 10, a red shift of absorption maxima was observed. The changes were rapid, and the effect was reversible. This system could prove to be useful in fabricating nanosensors for detecting the pH or pH changes of surrounding aqueous medium.

효모배지용 당밀의 청징법에 관하여 (Molasses clarifying method used by lime-phosphate for yeast culture)

  • 임억규
    • 미생물학회지
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    • 제19권3호
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    • pp.121-127
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    • 1981
  • The constituents of molasses and effect of pH precipitate formation in molasses solution, vary according to its producing districts. The formation of precipitation is not so changeable in the range of buffering zone of molasses solution(pH4.3-6.3) in philippine molasses according to the change of pH value. On lower or higher than the range of buffering zone, the precipitation is increased from pH 4.3 to 2.8 and from 6.3 to 8.1, it is decreased when pH value is lower or higher than the pH value range. For molasses clarifying, it had better adjust the pH of molasses solution to neutral or weak alkali range out of the alkai side of the buffering zone, with lime solution. And then, add the calcium super phosphate solution to pH value of alkali side in buffering zone, as much as the pH of clarified molasses solution can reach to middle value in buffering zone. For the equilibrium of pH value on clarifying molasses, it takes plenty of time more than 6 hours.

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$(P_{1},P_2)$-PLP 의 해법에 관한 연구 (An Efficient Solution Procedure for $(P_{1},P_2)$)

  • 손기형
    • 한국경영과학회지
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    • 제17권1호
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    • pp.17-30
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    • 1992
  • This paper concerns with (p$_{1}$, p$_{2}$)-Plant Location problem in which entire set of candidate sites for facility locations is divided by two overlapping subsets, each of which with its own number of facilities to be established. We propose an algorithm which attempts to solve the Lagrangean dual of (p$_{1}$, p$_{2}$)-PLP by dividing sub-problem into twop-Plant Location Problems and solving them based on the convexity of the Lagrangean dual problem with respect to the number of facilities to be established. In doing so, Orthogonal Move procedure is proposed to provide easy-to-obtain lower bound to the Lagrangean Dual of (p$_{1}$, p$_{2}$)-PLP. Computational experience is reported.

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Partial Purification of Factors for Differential Transcription of the rrnD Promoters for Ribosomal RNA Synthesis in Streptomyces coelicolor

  • Hahn, Mi-Young;Roe, Jung-Hye
    • Journal of Microbiology
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    • 제45권6호
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    • pp.534-540
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    • 2007
  • The Streptomyces coelicolor A3(2) genome contains six operons (rrnA to F) for ribosomal RNA synthesis. Transcription from rrnD occurs from four promoters (p1 to p4). We found that transcripts from the p1 and p3 promoters were most abundant in vivo in the early exponential phase. However, at later phases of exponential and stationary growth, transcripts from the p1 promoter decreased drastically, with the p3 and p4 transcripts constituting the major forms. Partially purified RNA polymerase supported transcription from the p3 and p4 promoters, whereas pure reconstituted RNA polymerase with core enzyme (E) and the major vegetative sigma factor ${\sigma}^{HrdB}$ ($E{\cdot}{\sigma}^{HrdB}$) did not. In order to assess any potential requirement for additional factor(s) that allow transcription from the p3 and p4 promoters, we fractionated a partially purified RNA polymerase preparation by denaturing gel filtration chromatography. We found that transcription from the p3 and p4 promoters required factor(s) of about 30-35 kDa in addition to RNAP holoenzyme ($E{\cdot}{\sigma}^{HrdB}$). Therefore, transcription from the p3 and p4 promoters, which contain a consensus -10 region but no -35 for ${\sigma}^{HrdB}$ recognition, are likely to be regulated by transcription factor(s) that modulate RNA polymerase holoenzyme activity in S. coelicolor.

까다로운 식습관을 가진 유아와 부모의 영양지수와의 관련성 (Correlation of the Nutrition Quotient between Parents and Picky Eaters in Preschoolers)

  • 염마영;최은영
    • 한국식품영양학회지
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    • 제36권2호
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    • pp.103-113
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    • 2023
  • This study investigated the correlation between parents' nutrition quotient (NQ) and the nutrition quotient of Korean preschoolers (NQ-P) of picky eaters (PE) aged five years living in Dobong-gu, Seoul. The questionnaire was conducted online by parents of 187 preschoolers between May 25 and June 5, 2020. PE was defined as an average score of 3 or more on the picky eating questionnaires; non-picky eaters (NPE, n=120) and PE (n=67). The correlation between preschoolers and their parents was assessed using the NQ-P and NQ, respectively. Compared to the NPE, picky eating (p<0.001) was significantly higher, and vegetable preference (p<0.001), NQ-P (p<0.05), moderation dimension (p<0.05), frequency of vegetable intake (p<0.05) of balance dimension, and processed beverages (p<0.01) of moderation dimension were significantly lower in the PE. The correlation between the NQ and NQ-P was related to the diversity (p<0.05), moderation (p<0.05), and environment (p<0.01) of NQ in the NPE and not related to the PE. PEs should increase their frequency of vegetable intake and reduce their intake of processed beverages. To increase the NQ-P of PE, parents should eat a balanced diet. Future studies on the NQ-P of preschoolers aged 3 to 5 are needed.