Four new compounds from the bulbs of Lycoris aurea with neuroprotective effects against CoCl2 and H2O2-induced SH-SY5Y cell injuries

An Jin,Xuelian Xiang,Yun-Yun Zhu,Heng-Yi Yu,Hui-Fang Pi,Peng Zhang,Han-Li Ruan 대한약학회 2014 Archives of Pharmacal Research Vol.37 No.3

Three new alkaloids, 2a-hydroxy-6-O-n-butyloduline,O-n-butyllycorenine, (-)-N-(chloromethyl)lycoramine(1–3), and a new phenolic compound, ((7S)-7-(4-hydroxyphenyl)-7-hydroxypropyl)-20-methylbenzene-30,60-diol (14), along with ten known alkaloids (4–13), wereisolated from the bulbs of Lycoris aurea collected fromHuaihua County of Hunan Province, China. Their structureswere elucidated by spectroscopic methods includingHRESIMS, UV, IR, and NMR. All the isolated compoundswere tested for their neuroprotective effects against CoCl2and H2O2-induced SH-SY5Y cell death. Compounds 1–7and 10 exhibited significant neuroprotective effects againstCoCl2-induced SH-SY5Y cell injury, while compounds1–5, 7, 10 and 12 showed obvious neuroprotective effectsagainst H2O2-induced SH-SY5Y cell death.

Effects of Quenching Methods and Aging Processes on the Crushing Properties and Microstructure of Al–Zn–Mg Alloy Thin-Walled Square Extrusions

Hui Guo,Jin Zhang,Cheng Wang,Yun‑lai Deng 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.8

In this study, the effects of different (online quenching and offline quenching) quenching methods and aging processes (T6and T73) on the crashworthiness and microstructural evolution of three Al–Zn–Mg alloys (G1–G3) were studied by conductingtensile test and axial compression tests at room temperature, combined with optical metallography, electron back scattereddiffraction, and transmission electron microscopy microstructural observations. The obtained results revealed that thecrushing properties of three different Al–Zn–Mg alloys subjected to different quenching methods and aging processes weresignificantly different. Their crushing energy absorption of are ranked as follows: G1 > G3 > G2. The highest total energyabsorption gap (between T6 and T73) is the G1 alloy, and the lowest one is the G3 alloy. The largest total energy absorptiongap between the two quenching methods is the G3 alloy, and the smallest one is the G1 alloy. The G2 alloy with the largesttotal amount of Zn + Mg has the highest number density of matrix precipitates, the largest precipitate gap (between T6 andT73) and the smallest precipitate gap between the two quenching methods. The G3 alloy with the largest Zn/Mg ratio hasthe smallest number density of matrix precipitates, the minimum precipitation gap (between T6 and T73) and the maximumprecipitation gap between the two quenching methods. The G1 alloy with the lowest Zn/Mg ratio has the smallest size ofgrain boundary precipitates and PFZ width, while their largest values are obtained for the G3 alloy with the maximum Zn/Mg ratio. As a crushing resistant structural material, the crushing properties is improved without reducing the strength. Theratio of Zn/Mg should be controlled within the range of 4.57–6.15, while the total amount of Zn + Mg should be controlledwithin the range of 6.18–7.01.

Effects of Cooling Rate on the Microstructure and Tensile Properties of Wire-Arc Additive Manufactured Ti–6Al–4V Alloy

Hui‑Jun Yi,Jin‑Woo Kim,Young‑Lak Kim,Sangyong Shin 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.8

Wire-arc additive manufacturing has emerged as a technology that could replace the conventional manufacturing processof titanium alloys. However, it produces a coarse β grain, which can accumulate via several deposited materials, resulting isstrong texture and anisotropy. To investigate potential solutions, the effects of the cooling rate on the resulting microstructureand tensile properties were studied. The cooling rate of the deposited materials was adjusted by interpass temperaturecontrol. Under rapid cooling, fine α + α′ grain with a low aspect ratio were observed and tensile and hardness propertieswere also improved.

Sol-Gel법을 이용한 다공성 Silica Ceramic 합성에 있어서 물이 겔화시간 및 평형농도에 미치는 영향에 관한 연구

이진휘,김화중,이준 서울産業大學校 1992 논문집 Vol.35 No.1

본 연구에서는 sol-gel process에 의하여 silcon계 다공성 ceramic물질을 합성하고, 합성 과정에서 중요하게 작용하는 인자들을 조사하였다. 중요한 인자들로 여러가지를 들수 있는데, 본 연구에서는 gelation time과 FT-IR을 이용한 최종 생성물의 화학 구조 조사에 의하여, 반응이 평형 상태에 도달하는 데 요구되는 물의 영향에 대하여 조사하였다. 실험 결과 EtOH/TEOS molar ratio가 7.6일 때, 반응이 평형에 도달하는데 소요되는 물의 양은 약 11mole인 것으로 사료되었다. The synthesis of porous silica ceramic material using sol-gel process was performed and the influencing factors during the synthesis were evaluated. Among several influencing factors, however, in this research program, the equilibrium concentrations of H₂O during hydrolysis and poly-condensation were studied based on the investigations of gelation time and chemical structures for the final porous ceramic materials using FT-IR. The results suggested that the equilibrium concentration of H₂O was about 11 moles for 7.6 of EtOH/TEOS molar ratio.

식이 단백질의 급원에 따른 당뇨쥐의 혈당 및 혈청지질에 미치는 영향

이수진,김영진,박수정,김희정,이윤희,유영상 동아시아식생활학회 1997 동아시아식생활학회지 Vol.7 No.2

This study was designed to find out the effects of soybean protein and milk protein between nondiabetic and diabetic rats. The experimental results are summarized as follows. 1. Total food intake was higher in diabetic soybean protein group than other groups but it was not significant. 2. The change of body weight was lower in diabetic soybean protein group than other groups and the soybean protein was effective to maintain the ideal body weight. 3. The effects of lowering total cholesterol and glucose in serum was higher in soybean protein groups than the milk protein groups.

효과적인 다차원 분석을 지원하는 스프레드시트 방식의 OLAP 인터페이스 설계 및 구현

윤민희,김진호,문양세 강원대학교 정보통신연구소 2006 정보통신논문지 Vol.10 No.-

OLAP systems support effectively data analysis over a large volume of business data to make decisions for an enterprise. In order to process data analysis efficiently, OLAP systems pre-compute the summary of business data over various dimensions and store them into data warehouses. Several specialized tools have been developed to display and to browse the results of complex analytical queries on data warehouses. In this paper, we developed a spreadsheet-like tool to support OLAP operations and to browse the results of analytical queries. Spreadsheet is one of the most popular and user-friendly data analysis tool. It also has lots of advantages, which is interactive, easy to learn, etc. Thus this paper implemented an OLAP tool using spreadsheet-style interface to analyze large OLAP data on World-Wide Web. Through this tool, users can process OLAP activities easily and effectively by using the same ways as well-known shreadsheet tools like Microsoft Excel.

Sol-gel법을 이용한 미세공 실리카 세라믹의 기공구조 변화에 관한 연구

이진휘,연만형,정은정,박노혁 서울産業大學校 1996 논문집 Vol.43 No.1

솔-젤법에 의하여 제조된 미세공 실리카 세라믹에 대하여 N₂-adsorption isotherm 및 TEM에 의하여 기공구조 변화를 조사하였다. Group 1, 2 및 3의 경우 물의 양이 각각 11, 5.5 및 3.8mole까지는 급격히 surface area의 증가를 보이다가 그 이후에는 완만한 상승을 보이는데, 이것은 앞의 실험에서 보인[4.5]gelation time 및 FT-IR의 실험결과와 일치하는 것이다. 서로 다른 물의 양에 대하여 BET surface area와 Cumulative surface area의 차이가 Group 1서 Group 3으로 옮아감에 따라 커지는 것은 용매의 양은 감소하는 반면 TEOS의 양 증가로 인하여 물과 TEOS의 반응이 원활하지 못한 결과로 덜 발달된 polymer에 기인한 작은 particle에 의하여 형성된 작은 기공들에 기인한 것으로 사료된다. 이와같은 기공구조는 TEM의 결과에 의하여 확인할 수 있다. Group A에서 E쪽으로 갈수록 물의 양의 증가에 기인하여 surface area는 증가하며, Group a에서 d쪽으로 갈수록 물의 양의 감소에 기인하여 surface area는 감소한다. N₂-adsorption isotherm and TEM were used to investigate the micro-porous silica ceramic prepared by sol-gel process to find the structural changes of pores. In the case of Group 1, 2 and 3, the drift of the surface area increased steeply till the amount of water 11, 5.5 and 3.8 moles individually and after that showed increased smoothly. It is the same results as the gelation time and the FT-IR[4.5]. It is the reason that the differences of BET and Cumulative surface area become larger proportionally as moving from Group 3 that the reaction of water and TEOS is less active, caused by using decreased quantity of water but increased TEOS, and therefore the smaller pores by the smaller particles were formed. It was identified by TEM. The surface area is increased by the increased water as moving from Group A to Group E, and decreased by the decreased water as moving from a to e.

고속의 GaAs SRAM 을 위한 새로운 센스 앰프의 설계 연구

조희철,김선옥,이웅호,윤진섭,이진구 동국대학교 산업기술대학원 1993 산업기술논문집 Vol.1 No.-

A new sense amplifier is designed in order to realize high-speed GaAs SRAM's. The Schematics are similar to "a source coupled differential amplifier" execept that two analyzed using basic FET current equations. The transconductance of the new sense amplifier is approximately 3.5 times larger than that of the conventional sense amplifier. Output high voltage is reduced to about 0.64V, therefore, the time which reached V_(max) are reduced also. The simulation results show that the access time of 0.9ns and the power dissipation of 12.2mW are achieved in GaAs 16bit SRAM's.

실리콘 웨이퍼 공정용 알루미나 정전척의 제작과 특성에 관한 연구

천희곤,조동율,이영섭,박용균,최성호,정광진,Serguei Spoutai 울산대학교 기계부품 및 소재 특성평가연구센터 1999 연구보고서 Vol.1999 No.-

정전척의 유전체 물질로 열전도도와 유전특성 그리고 기계적 특성이 우수한 알루미나에 TiO₂첨가하여 유전체의 비저항을 변화시켜서 정전척(electrostatic chuck)에서 발생하는 정전력인 쿨롱힘(coulomb force)과 존슨-라벡힘(Johnsen-Fahbeck firce_의 영향을 규명하려 하였다. 그리고 비저항, 인가전압, 온도, 습도가 정전력에 어떠한 영향을 주는지 고찰하였으며, 인가전압에 따른 응답 특성에 관하여 고찰하였다. Alumina electrostatic chucks for silicon wafer process with wide range of electrical resistivity were fabricated by controlling the amount of TiO₂ addition (0 wt%, 1.3 wt%, 2 wt%, 2.8 wt%). The dependence of electrostatic force on applied voltage, temperature and humidity was investigated. In addition, response characteristics on applied voltage and relationship between electrical resistivity and electrostatic force characteristics such as Coulomb force and Johnsen-Rahbeck force were discussed

하약골 수조작술에 의한 폐구성 과두걸림 환자의 치료

김진환,김희정 大韓顎顔面成形再建外科學會 2000 Maxillofacial Plastic Reconstructive Surgery Vol.22 No.1

In general, treatment of the patients with closed lock divides into a conservative and a surgical treatment. Surgical treatment has been often applied in case that occlusal splint therapy was not effective on the patient with closed lock. In recent, some clinicians reported good results with mandibular manipulation. Three patients complained limitation of month opening-(mean mouth opening was 22.3mm) and TMJ pain. Articular discs were displaced anteriorly on MRI. Two patients didn't improve the symptoms with long term occlusal splint therapy. We applied mandibular manipulation after injection with 2% lidocaine into the upper joint space of the affected TMJ and directly inserted occlusal splint to all patients. At the follow-up check, mean mouth opening was 41.7mm. TMJ pain decreased, condyle and disc relationship was improved functionally on MRI.