녹색 형광체 LaPO₄:Ce^(3+),Tb^(3+)의 발광 특성

박중철 신라대학교 자연과학연구소 2004 自然科學論文集 Vol.13 No.-

LaPO_(4) : Ce^(3+), Tb^(3+) phosphor is most commonly used in three-band lamps as the green-emitting component. We have synthesized the alkali-metal doped LaPO_(4) : Ce^(3+), Tb^(3+) by a conventional solid-state reaction. This phosphor belongs to the monazite crystal group, as determined by X - ray analysis. We discuss luminescent properties of L_(a1-x)M_(x)PO_(4) : Ce^(3+) Tb^(3+) (M = Li, Na, and K) phosphor using X - Ray Defflaction (XRD), Scanning Electro Microscopy (SEM), and Photoluminescence (PL) spectrometer.

Sr₂Ru_1-xCu_xO_4-y(0.0≤x≤0.5) 화합물의 구조 및 전달 특성에 대한 연구

박중철,Park, Jung-Chul 대한화학회 2003 대한화학회지 Vol.47 No.6

고상반응으로 $Sr_2Ru_{1-x}Cu_xO_{4-y}(0.0{\le}x{\le}0.5)$ 화합물을 합성하였다. X-선 회절 분석 결과에 대한 Rietveld 정밀화로부터 합성된 $Sr_2Ru_{1-x}Cu_xO_{4-y}$ 화합물은 $0{\le}x{\le}0.30$의 Cu 치환 범위에서는 모두 단일상의 정방정계 구조를 갖는 $K_2NiF_4$ 형태의 구조를 취하지만, $0.4{\le}x{\le}0.5$의 범위에서는 미량의 $Sr_2CuO_3$ 화합물의 회절 피이크가 관찰되는 이중상을 갖는 화합물로 존재한다는 사실을 알 수 있었다. $Sr_2RuO_4$ 화합물의 Ru자리에 Cu 이온을 부분적으로 치환할 때의 전이금속 이온인, Ru와 Cu이온의 원자가 상태는 X-선 전자 분광법으로 확인하였다. $Ru\; 3p_{3/2}$ 전자와 $Cu\; 2p_{3/2}$ 전자의 결합에너지 측정으로부터 $Ru^{4+},\;Cu^{2+}$를 갖는 것으로 확인되었다. $Sr_2RuO_4$ 화합물의 Ru 자리에 치환하는 Cu 이온의 농도를 증가할수록 $Ru-O1({\times}4)$ 와 $Ru-O_2({\times}2$)의 결합길이 차이가 ${\Delta}=0.1329 {\AA}Sr_2RuO_4$ 경우)에서 ${\Delta}=0.0383 {\AA}(Sr_Ru_{0.7}Cu_{0.3}O_{4-y}$ 경우)으로 변하며, c/a 역시 감소하는 경향을 나타내고 있다. 따라서, $Sr_2RuO_4$ 화합물의 Ru 자리에 Cu 이온을 치환함에 따라 $RuO_6$ 팔면체의 국부 대칭성의 변화에 의해 결정구조가 정방정계로의 변화를 수반하면서, 이에 따른 $Sr_2Ru_{1-x}Cu_xO_{4-y}$의 전달특성이 금속에서 반도체로 변화한다. $Sr_2Ru_{1-x}Cu_xO_{4-y}(0.0{\le}x{\le}0.5)$ compounds were prepared using a conventional solid state reaction. Based on the Rietveld refinements of X-ray diffraction results, it is revealed that $Sr_2Ru_{1-x}Cu_xO_{4-y}$ compounds are the single phases with K2NiF4 type tetragonal system in the range of 0=x=0.3, while the mixed phases of$Sr_2RuO_4$ and $Sr_2CuO_3$ in the range of $0.4{\le}x{\le}0.5$. By means of X-ray photoelectron spectroscopy, the valence states of Ru and Cu in $Sr_2Ru_{1-x}Cu_xO_{4-y}$, have been confirmed to 4+ and 2+, respectively. The bond length difference between $Ru-O_1 ({\times}4)\;and\;Ru-O_2 ({\times}2)\;in\;RuO_6$ octahedron is gradually decreased with increasing Cu content in $Sr_2Ru_{1-x}Cu_xO_{4-y}$, which results in the lower c/a ratio. So, it might be assured that the variation of local symmetry of $RuO_6$ octahedron is very closely related to the transporting property of $Sr_2Ru_{1-x}Cu_xO_{4-y}$ compounds. The behavior of resistivity discloses that the metallic property in $Sr_2RuO_4$ changes into the semiconducting one in proportion to the Cu content in $Sr_2Ru_{1-x}Cu_xO_{4-y}$.

[지상15]흰쥐의 발기반사궁을 구성하는 L6 후근신경절에 testosterone이 미치는 영향

박중철,박병구,송대용,이진숙,최병영,강호석,조병필 대한체질인류학회 2004 대한체질인류학회 학술대회 연제 초록 Vol.47 No.-

적색 형광체, YVO₄: Eu3+ 합성 : 적색 형광체, YVO₄: Eu3+ 합성

박중철 신라대학교 자연과학연구소 2008 自然科學論文集 Vol.17 No.-

성공노화의 실제

박중철 대한임상노인의학회 2011 대한임상노인의학회지 Vol.12 No.1

의과대학생을 위한 죽음학 수업

박중철 연세대학교 의과대학 2020 의학교육논단 Vol.22 No.3

The aim of modern medicine is to prolong life by fighting death. Doctors have traditionally believed that this was an ethical good deed. The negative connotation surrounding death has led to the avoidance of terminally ill patients. But in a modern society where death is medicalized, doctors have to see dying patients every day and are in a state of guilt from implementing meaningless life-sustaining treatments. Therefore, medical schools should allow medical students to embrace a new perspective through death education. Yonsei University Medical College has implemented death education since 2017 as an optional class for first and second year medical students. Students watch videos related to death once a week for 6 weeks and submit their reflections by e-mail. The professor reads the students’ reflections and gives them weekly feedback. Through this coursework, students realize that death is not a medical event, but rather a part of life and completion. The ultimate purpose of death education is to transform blind life-absolutist identity into narrative identity.

Growing Organized Hematomas Following Gamma Knife Radiosurgery for Cerebral Arteriovenous Malformation : Five Cases of Surgical Excision

박중철,안재성,권도훈,권병덕 대한신경외과학회 2015 Journal of Korean neurosurgical society Vol.58 No.1

Organized hematoma is a rare complication that can develop following gamma knife radiosurgery (GKS) for cerebral arteriovenous malformation (AVM). Here, we describe 5 patients with growing organized hematomas that developed from completely obliterated AVMs several years after GKS. The patients were 15, 16, 30, 36, and 38 years old at the time of GKS, respectively, and 3 patients were female. Four AVMs were located in the lobe of the brain, and the remaining AVM were in the thalamus. Between 2–12 years after GKS, patients developed progressive symptoms such intractable headache or hemiparesis and enhancing mass lesions were identified. Follow-up visits revealed the slow expansion of the hematomas and surrounding edema. Steroids were ineffective, and thus surgery was performed. Histology revealed organized hematomas with a capsule, but there was no evidence of residual AVMs or vascular malformation. After surgery, the neurological symptoms of all patients improved and the surrounding edema resolved. However, the hematoma continued to expand and intraventricular hemorrhage developed in 1 patient whose hematoma was only partially removed. GKS for cerebral AVM can be complicated by growing, organized hematomas that develop after complete obliteration. Growing hematomas should be surgically evacuated if they are symptomatic. Radical resection of the hematoma capsule is also strongly recommended.

[‘우리 사회의 의사조력자살 법제화’에 대한 논평] 무엇으로부터의 EXODUS인가?

박중철 한국의료윤리학회 2022 한국의료윤리학회지 Vol.25 No.4

South Korea has low scores on both the Happy Planet Index (HPI) and Quality of Death Index (QDI) in comparison to other countries with similar levels of economic development. As the number of hospital deaths increases, so too does the number of people experiencing miserable deaths due to the availability and perhaps misuse of life-sustaining treatment. However, given the current individualized social structure, an increasing number of people will spend the end of their lives in elderly care facilities and hospitals, experiencing miserable deaths. Although many people fear misery at the end of life, a realistic solution to this problem has not yet been found in South Korea. For this reason, a recent proposal to legalize physician-assisted suicide in South Korea has received strong public support. This article argues that past opportunities for meaningful public discussions concerning dignified dying have been squandered and that what is needed at this point is not further legislation that enables us to avoid thinking about these issues but rather mature dis-cussions concerning how we want to die.

이달의 말씀 : 6 월의 설교 ; 화평케 하는자

박중철 기독교한국문제연구회 1991 교회와 한국문제 Vol.15 No.-

만성통증의 최신 약물치료

박중철,김정현,최윤선 대한의사협회 2010 대한의사협회지 Vol.53 No.9

Chronic pain is associated with disabling physical and emotional symptoms. Patients with chronic pain utilize more health services, have an impaired sense of well-being and frequently experience anxiety or depression. Unfortunately, treatment for chronic pain is not always correctly targeted, which leads to a reduced quality of life. Treatment of chronic pain involves a comprehensive approach using medication and functional rehabilitation. The usual approach for mild to moderate pain is to start with nonopioid analgesics. Also, trying antidepressant drugs for sleep loss and gabapentin for neuropathic pain or fibromyalgia is appropriate. For moderate to severe chronic pain, opioid analgesics can be used without any serious side effects if adequately used at the right dosage. It is important to provide guidance on the safe use of analgesics and other psychoactive drugs. Dosing of acetaminophen should be limited to avoid liver toxicity, and topical analgesics are preferred for focal pain. Full-dose nonsteroidal anti-inflammatory drugs should not be used for more than short periods, in order to avoid gastrointestinal, renal, and cardiovascular complications. Mechanisms of analgesia, drug selection, and recommendations for clinical usage for the management of chronic pain are reviewed in this paper.