Effects of Pilger Rolling and Heat Treatment on Microstructure and Corrosion Resistance of Ag-electroplated 304 Stainless Steel Tubes

Hyun Park,Woo‑Jin Lee,Jae‑Han Son,Han‑Kyun Shin,Sung‑Kyu Hong,Hyo‑Jong Lee 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.8

We introduce a cost-effective method that combines electroplating with metal cold working processes to manufacture compositetubes with robust corrosion resistance. First, a 3-step electroplating process was developed to form an adhesive anduniform Ag coating on the outer wall of a 304 stainless steel tube. The process consisted of a Ni-strike step for removing thepassivation layer of the initial 304 tube, Cu deposition for smoothing the surface by adding a buffer layer, and Ag deposition. To reinforce the interfacial adhesion between the electroplated layers and the 304 tube and increase the area of the Ag coating,a pilger rolling or pilger rolling + heat-treatment process was performed after the Ag electroplating process. Scanningelectron microscopy of the composite tubes after each process indicated that the as-deposited Ag coating changed fromhaving a rough to smooth surface after only pilger rolling and with additional heat treatment. Electron backscatter diffractionanalysis of the microstructures and textures of the tubes revealed that dynamic recrystallization occurred extensively duringpilger rolling, resulting in the formation of a relatively defect-free grain structure without heat treatment. Furthermore,electrochemical polarization curves determined that the Ag-coated composite tubes are superior to the uncoated 304 tubein terms of corrosion resistance under Cl−atmosphere, owing to the formation of a AgCl passivation layer during testing. Surface analysis of the composite tubes suggests that the properties of the AgCl passivation layer are related to the grainsize of the Ag coating and the density of plastic-deformation-induced defects.

오감(五感)적 요소를 접목한 브랜드 스페이스 연출 계획 -마임 화장품 프레쉬가든을 중심으로-

김소현,임하영,장효실,최혜원,이진민,장미정,이성애 숙명여자대학교 산업디자인연구소 2017 숙명디자인학 연구 Vol.24 No.-

인간이 갖고 있는 감각 기관은 시각, 청각, 후각, 촉각, 미각의 총 다섯 가지로, 이를 모두 활용 할 때 이상적 공간 상호작용이 가능하다. 본 연구는 화장품의 공간 연출 계획 시 오감적 요소를 접목하여 브랜드 이미지를 구축하는 일련의 프로세스를 밝히는데 목적이 있다. 이에 본 연구는 2017년 3월~6월 15주간 숙명여대 환경디자인학과 <융합연출디자인> 수업에서 진행된 수업의 결과물로서 작업물을 정리하였다. 그 결과 본 연구는 제품이나 서비스를 직접 경험할 수 있도록 다양한 엔터테인먼트적 요소를 결합하여 기능적 만족감과 더불어 체험적 만족감 제공하는 오감적 디스플레이를 제안하였다. 본 연구는 오감을 활 용한 뷰티 쇼룸으로 감각을 공간에 어떠한 방식으로 적용할 것인지에 대한 정립을 했다는 데에 의의가 있다. 아울러 다양한 매체와 공간의 개념이 일반화 되어 가는 오늘날 기업 환경 속에서 오감적 체험을 기반으로 한 공간연출은 가상의 공간속에서도 유연하게 적용 가능한 디스플레이 요소로 확인되었다. 또한 본 연구는 향후 이와 관련된 쇼룸 공간 개발에 있어서 기초 자료로 활용될 것으로 기대된다.

근적외선 분광분석법을 이용한 당화혈색소의 측정 및 혈당측정과의 관계

백주현,김효진 동덕여자대학교 종합약학연구소 2003 동덕약학연구지 Vol.7 No.-

Measurement of hemoglobin A_(1c) (glycated hemoglobin) has been recommended for the long-term assessment of glycemic control in diabetic patients. Near infrared spectroscopy and partial least square (PLS) regression were applied to the quantitative analysis of physiological hemoglobin A_(1c) (Hb A_(1c)) level from diabetics. Standard errors of calibration (SEC) and standard errors of prediction (SEP) was 0.69, 0.85, respectively. Calibration R value for calibration and prediction was 0.8882, 0.8834, respectively. We suspected Hb A_(1c) as a critical influence factor on non-invasive blood glucose measurement, because it is formed by the irreversible combination of glucose with the N-terminal of a β-chain. The study was carried out in diabetics by PDA type NIR spectrometer with a fiber optic probe. PLSR and error grid analysis (EGA) were applied to determine only blood glucose level and HbA_(1c) compensated-blood glucose level. Calibration result of glucose level including HbA_(1c) was better than the other. It showed probability of non-invasive HbA_(1c) measurement and reliability of non-invasive blood glucose monitoring accuracy.

벼 Small HSP의 발현에 의한 대장균의 고온 stress 하에서의 내성의 증가

이병현,이효신,원성혜,조진기 경북대학교 농업과학기술연구소 1999 慶北大農學誌 Vol.17 No.-

This study was conducted to detect the allelopathic effect of water and ethanol extracts from 4 plant species (Lactuca sativa L., Ambrosia elatior L., Oenothenra odorata Jasp., Ginkgo biloba L.) on germination and growth of lettuce seeds. A little bit higher inhibitory effect was obtained in ethanol extracts rather than water extracts. Allelopathic effects varied in the source of extracts and concentrations of 4 plant species and the highest allelopathic effect appeared in 10% solution, regardless of plant species.

전기품질비용시스템의 구축에 관한 연구

서현진,고성효,이경찬 제주대학교 관광산업연구소 2001 産經論集 Vol.15 No.2

EPx 자동생화학분석기와 컴퓨터간의 양방향 통신 시스템 구축

박기현,전효진 啓明大學校 醫科大學 1995 계명의대학술지 Vol.14 No.4

It has been understand that a laboratory information system(LIS) plays an important role in a hospital information system(HIS). However, few HIS has been equipped with a fully automated LIS. This is partly because, in order to achieve a fully automated LIS, there are many testing equipment has its own communication protocol. In this paper, a bi-directional communication system between an ABBOTT SPECTRUM EPx auto-chemical analyzer and a PC is constructed. With the communication system, it is possible that a PC controls an EPx's operations and that the PC receives test results form the EPx automatically. RS-232C serial ports are used in order to make bi-directional communication possible between them

Inhibitory Effect of Clavicepitaceae on Serotonin Release out of Human Platelets and Human Platelet Aggregation

박화진,--,--,--,--,--,-- THE KOREAN SOCIETY FOR BIOMEDICAL LABORATORY SCIEN 2004 Journal of biomedical laboratory sciences Vol.10 No.1

We have investigated the effects of hypha-water extracts (HWE), fruit body-water extracts (FWE) and cordycepin from Cordyceps militaris on serotonin release out of human platelets and human platelet aggregation. HWE and FWE inhibited the release of [^(3)H]-serotonin from human platelet stimulated by thrombin (2 U/ml) or collagen (20 ㎍/ml) in a dose-dependent manner. Furthermore, cordycepin, a major component of Cordyceps militaris, inhibited the human platelet aggregation induced by collagen (10 ㎍/ml) in a dose-dependent manner. These results suggest that cordycepin containing in HWE and FWE may inhibit the serotonin release by suppressing the collagen-induced human platelet aggregation. Accordingly, our data demonstrate that HWE and FWE containing much cordycepin might have antithrombotic and antimigrainous functions.

역형성 핍지교세포종의 임상 분석에 대한 연구

이현성,최우진,고영초,이채혁,박효일 인제대학교 백병원 2002 仁濟醫學 Vol.23 No.5

Objectives : In this study, the author reviewed the clinical features of the patients with anaplastic oligodendroglioma and evaluated the efficacy of surgery, radiation therapy and chemotherapy as a treatment modality. The study was intended to provide the standardized treatment option for this rare disease. Methods : The author present ten cases of pathologically proven anaplastic oligodendrogliomas from 1988 to 2002. A retrospective analysis of clinical presentation. radiological and pathological features, and the effectiveness of treatment was performed and the factors affecting prognosis were investigated. Fesults : The ten patients comprised of four males and six females. The mean age at diagnosis was 34.4 (8-70). The mean follow-up duration was 40.5 months. and two patents died of tumor progression during the follow-up(70, 86 months, respectively). The most common presenting symptom was seizure(70%). All patients underwent surgery and the tumors were removed as much as possible. Postoperatively, Radiation therapy was applied to seven patients. and PCV(procarbazine CCNU-vincristine) based chemotherapeutic agent was administered to five patients. Total removal was achieved in five cases and subtotal removal was possible in the rest. In the group with PCV therapy, complete remission was observed in two, partial remission, stable disease, and disease progression to death in one, respectively. The patients well tolerated the toxicity of chemotherapy. During the follow-up, tumor recurrences were observed in four patients, and they were treated with additional operations and/or chemotherapy. Mixed anaplastic oligoastrocytoma showed earlier recurrence than anaplastic oligodendrogliomas in this study(P=0.014), but the other clinical factors and treatment modalities were not related to the time of recurrence of the tumor. Conclusions : In this study, the authors confirmed the good response of postoperative radiological treatment and chemotherapy in patients with anaplastic oligodendroglioma. PCV chemotherapy should be considered as primary treatment method for the patients with anaplastic oligodendroglioma.

HMG-CoA 환원효소 억제제에 의한 ICAM-1 유전자의 발현조절

김현진,정효균,홍우정,김군순,조영석,김도희,채수흥,구본정,송민호,노흥규,김영건 충남대학교 의과대학 지역사회의학연구소 2001 충남의대잡지 Vol.28 No.1

Background : ICAM-1 act as one of major adhesion molecules in the atherosclerotic lesion. ICAM-1 expression is mainly regulated at the level of transcription and depend on IFN-γ signal transduction pathway in which the STAT1 transcrption factor is a critical intermediate. IFN-γreceptor not only initiates tyrosine 701 phosphorylation of STAT1 by Jak1 and Jak2, but also phosphorylates serine 727 through the activation of Raf-1/MAP kinases. HMG-CoA reductase inhibitors have anti-atherosclertic effects, beyond normalization of hypercholesterolemia, by directly acting on endothelial cells, macrophages and vascular smooth muscle cells. HMG-CoA reductase inhibitors suppress the synthesis of isoprenoid intermediates such as geranylgeranyl-pyrophosphate or farnesylpyrophosphate. These effects results inhibitors suppress the synthesis of isoprenoid intermediates such as geranylgeranyl-pyrophosphate or farnesylpyrophosphate. These effects results inhibition posttranslational farnesylation and geranyl-geranylation processing of small GTP-binding preoteins and inhibition of normal signaling activities. Method : We made several 5'-deletion constructs of rat ICAM-1 promoter and analyzed the promoter activities by measuring the luciferase activity after transfection into ECV304 cells and smooth muscle cells. We checked the level of total and phosphorylated STAT1 protein by immunoblot analysis using specific antibodies. Results : Lovastatin inhibits IFN-γ-induced ICAM-1 gene expression in the ECV304cell. The cells pretreated with PD98059, MEKK inhibitor showed significantly low ICAM-1 RNA induction with IFN-γ stimulatio. IFN-γ induced phosphorylation of tyrosine 701 was not significantly changed by the pretreatment of lovastatin. But lovastatin suppresses IFN-γ-induced phosphorylation of ERK1/ERK2 which are responsible for the seine 727 phosphorylation in STAT1. Conclusion : We showed that HMG-CoA reductase inhibitors, lovastatin, suppresses IFN-γ mediated ICAM-1 gene expression through the inhibition of transcription. HMG-CoA reductase inhibitor suppresses IFN-γ-induced phosphorylation of serine 727 in STAT1 through the modulation of MAP kinases.

矢狀分割骨切斷術에 依한 顎矯正術의 統計學的 硏究

辛曉根,陳宇政,李俊禮,金晤煥,李炫尙 大韓顎顔面成形再建外科學會 1997 Maxillofacial Plastic Reconstructive Surgery Vol.19 No.2

Recently, combined with social complexity, increment of medical demand and supply and the change of esthetic category, admission and operation of the patients of facial deformity have been changed with annual change. This study was conducted in the concept of helping the overall character of orthognathic surgery in future understood and being an important index in the establishment of better treatment course, through the patient, on whom was operated orthognathic surgery via sagittal split ramal osteotomy in our Dept. of Oral & Maxillofacial Surgery, Chonbuk National University Hospital from 1991. 1. 1 to 1995. 12. 31. The results were obtained as follows. 1. The ratio of male to female was 1 : 1.33 and the ages between 16 and 25 year was 73.6%, and the mean age was 20.4 years. 2. The ratio of setback amount between 6 to 15mm was 84.6% and the advancement amount between 1 to 10mm was 89% and the mean amount of movement was 9.0mm in setback, and 3.6mm in advancement. 3. After removal of maxillomandibular fixation(MMF), the distinction of sex was not statistically significant in ROM. 4. The ROM following methods of fixation was statistically significant in 3rd(P<0.05), 8th, and 12th week(each P<0.01), with faster rehabilitation in rigid fixation which had shorter MMF period. 5. The rehabilitation of ROM following the operation methods was statistically significant in 1st(P<0.05), 2nd, 3rd, 4th, 6th, 8th, and 12th week(each P<0.01) with faster rehabilitation in the case of SSRO than Lefort I / SSRO (Two jaw surgery). 6. The rehabilitation of ROM following directions of mandibular movement did not manifest a statistically significant difference in both setback and advancement.