Eu³⁺ doped lutetium molybdenum oxides: Synthesis, optical properties, thermal behavior, and LED packaging

Cao, Chunyan,Xie, Along,Zhou, Tianliang,Zhong, Haichang,Lu, Xiangjun,Xie, An,Noh, Hyeon Mi,Jeong, Jung Hyun Elsevier 2020 Journal of luminescence Vol.217 No.-

<P><B>Abstract</B></P> <P>Some lutetium molybdenum oxides were synthesized through a solid-state reaction method. By adjusting the molar ratios of raw materials of Lu<SUB>2</SUB>O<SUB>3</SUB> (Eu<SUB>2</SUB>O<SUB>3</SUB>) to MoO<SUB>3</SUB>, Eu<SUP>3+</SUP> doped lutetium molybdenum oxides Lu<SUB>2</SUB>MoO<SUB>6</SUB>, Lu<SUB>2</SUB>Mo<SUB>2</SUB>O<SUB>9</SUB>, Lu<SUB>2</SUB>(MoO<SUB>4</SUB>)<SUB>3</SUB>, and Lu<SUB>6</SUB>MoO<SUB>12</SUB> were obtained. The materials were characterized by X-ray diffraction (XRD) patterns, scanning electron microscope (SEM) images, energy-dispersive spectra (EDS), diffuse reflection (DR) spectra, photoluminescence (PL) excitation and emission spectra, luminescence decay curves, and temperature dependent integrated emission spectra. Enhanced excitation and emission spectra were recorded at high temperatures. Possible energy transfer processes were proposed to explain the excitation and emission spectra. By combining some phosphors with near ultraviolet (NUV) chips, the obtained light emitting diodes (LEDs) gave red light under forward bias current. The results suggest that the obtained Eu<SUP>3+</SUP> doped lutetium molybdenum oxides have potential applications in phosphor converted based NUV LEDs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Eu<SUP>3+</SUP> doped Lu<SUB>2</SUB>MoO<SUB>6</SUB>, Lu<SUB>2</SUB>Mo<SUB>2</SUB>O<SUB>9</SUB>, Lu<SUB>2</SUB>(MoO<SUB>4</SUB>)<SUB>3</SUB>, and Lu<SUB>6</SUB>MoO<SUB>12</SUB> were obtained. </LI> <LI> The materials present different structures, morphologies, optical properties, and luminescece decay behaviors. </LI> <LI> Eu<SUP>3+</SUP> concentration dependent optical properties in Lu<SUB>2</SUB>MoO<SUB>6</SUB> were researched. </LI> <LI> Enhanced excitation and emission spectra were recorded under high temperatures in some materials. </LI> <LI> Red LEDs were obtained by packaging phosphors to NUV LED chips. </LI> </UL> </P>

The observation of children`s holding position to redesign elementary school chair for easy carrying and moving

Lu’lu’ Purwaningrum,Satoshi Muraki 대한인간공학회 2014 대한인간공학회 학술대회논문집 Vol.2014 No.5

Objectives. Carrying and moving chairs enable and improve learning activities at school, which leads to better quality of education. At elementary schools in Indonesia and other developing countries, only one size of chair has been used for all ages and grades, therefore, making it heavy for younger children. The objective of the present study was to observe the motion of carrying and moving an elementary school chair by children. Methods. A total of 41 children consisting of 16 Indonesian and 25 Japanese children (17 boys and 24 girls) aged 6, 7, 8 and 9 participated in this study. We used three elementary school chairs (1 Indonesian and 2 Japanese chairs). The participants carried and moved the chairs 3 m with an ordinary speed, and were allowed to hold any part of the chair that was convenient for them. We recorded their motion when carrying and moving the chair. Results. The chair was carried at the side or in front of the child’s body, and the chair being in a lateral position is the most popular method of carrying and moving (75%). In all methods, participants showed a preference in using two particular chair parts to hold the chair. Conclusions. Careful consideration is needed on the design of elementary school chairs from the perspective of the main methods and holding pattern for carrying and moving them, especially heavy chairs that are used in elementary schools in Indonesia.

The Observation of Children`s Holding Position to Redesign Elementary School Chair for Easy Carrying and Moving

( Lu`lu` Purwaningrum ),( Satoshi Muraki ) 한국감성과학회 2014 춘계학술대회 Vol.2014 No.-

Objectives. Carrying and moving chairs enable and improve learning activities at school, which leads to better quality of education. At elementary schools in Indonesia and other developing countries, only one size of chair has been used for all ages and grades, therefore, making it heavy for younger children. The objective of the present study was to observe the motion of carrying and moving an elementary school chair by children. Methods. A total of 41 children consisting of 16 Indonesian and 25 Japanese children (17 boys and 24 girls) aged 6, 7, 8 and 9 participated in this study. We used three elementary school chairs (1 Indonesian and 2 Japanese chairs). The participants carried and moved the chairs 3 m with an ordinary speed, and were allowed to hold any part of the chair that was convenient for them. We recorded their motion when carrying and moving the chair. Results. The chair was carried at the side or in front of the child`s body, and the chair being in a lateral position is the most popular method of carrying and moving (75%).

The Influence of Cigarette Smoke on the Epithelium of the Vestibule: an Electron Microscopic Study

Mukaddes E?refo?lu,Erol Selimo?lu,Muammer E?refo?lu,?zgen Vuraler 연세대학교의과대학 2003 Yonsei medical journal Vol.44 No.4

It is known that cigarette smoke induces cytological alterations on the respiratory and olfactory mucosa of the nasal cavity. We evaluated whether cigarette smoking had adverse effects on the epithelium of the vestibule, in the absence of any published ultrasutructural studies. We evaluated ten patients suffering from septum deviation, eight of whom were long-term smokers. While each layer of the epithelium obtained from the non-smokers consisted of a homogeneous cell population, each from the long-term smokers consisted of a heterogeneous cell population. The most prominent changes occurred in the shape and size of the cells and nuclei, the number and length of the cytoplasmic projections, the number and distribution pattern of the desmosomes, and the width of the intercellular spaces. We concluded that cigarette smoke produces hyperplastic and dysplastic changes, important factors related with cancer development, on the epithelium of the vestibule.

Effects of α-Si₃N₄ seeds and sintering additives on properties of porous silicon nitride ceramics fabricated by carbothermal reduction

Yuan Lu,Ji-Qiang Gao,Jian-feng Yang 한양대학교 세라믹연구소 2008 Journal of Ceramic Processing Research Vol.9 No.6

In this paper, porous Si3N4 ceramics were fabricated by carbothermal reduction between silicon dioxide and carbon [1]. The influences of α-Si3N4 seeds and sintering additives on the microstructure and mechanical properties of porous Si3N4 ceremics were investigated. XRD analysis proved the complete formation of a single-phase β-Si3N4. SEM analysis showed that the resultant porous Si3N4 ceramics had a fine microstructure and a uniform pore structure. The sintered sample with Lu2O3 as sintering additive showed finer, higher aspect ratio β-Si3N4 grains. The addition of Eu2O3 accelerated the densification of porous Si3N4 ceramics, decreased the porosity and increased the flexural strength. The addition of α-Si3N4 seeds accelerated the formation of the α-Si3N4 phase at a low temperature and the α-β phase transformation process at a high temperature. With an increase in the α-Si3N4 seeds content, the porosity decreased, and the flexural strength increased accordingly. In this paper, porous Si3N4 ceramics were fabricated by carbothermal reduction between silicon dioxide and carbon [1]. The influences of α-Si3N4 seeds and sintering additives on the microstructure and mechanical properties of porous Si3N4 ceremics were investigated. XRD analysis proved the complete formation of a single-phase β-Si3N4. SEM analysis showed that the resultant porous Si3N4 ceramics had a fine microstructure and a uniform pore structure. The sintered sample with Lu2O3 as sintering additive showed finer, higher aspect ratio β-Si3N4 grains. The addition of Eu2O3 accelerated the densification of porous Si3N4 ceramics, decreased the porosity and increased the flexural strength. The addition of α-Si3N4 seeds accelerated the formation of the α-Si3N4 phase at a low temperature and the α-β phase transformation process at a high temperature. With an increase in the α-Si3N4 seeds content, the porosity decreased, and the flexural strength increased accordingly.

Preventive Effects of Intracisternal Alphatochopherol on Cerebral Vasospasm in Experimental Subarachnoid Hamorrhage

SerdarKemalo?lu,Umit?zkan,FahriYilmaz,ErdemAK,HamitAcemo?lu,G?n?l?lmez,Ramazan?ım?ek,AbdurrahmanBakir 연세대학교의과대학 2003 Yonsei medical journal Vol.44 No.6

Dot Idea (.IDEA): A New Concept for an Incubation Program and Open Innovation Based on User Needs

Luís Felipe Maldaner,Luísa Simon,Carlos Eduardo de Souza Aranha 세계과학도시연합 2018 World Technopolis Review Vol.7 No.2

This paper discussed the application process of the Dot Idea program. The Dot Idea program is an incubation and open innovation program co-created by Unitec, an incubator at Tecnosinos Tech Park, and an SAP innovation team. The main objective of this study was to cover an existing gap in the literature regarding the practical application of an open innovation methodology. Many companies seek interaction with external parties to enable advancement toward identified innovation opportunities. Technology clusters, parks, and incubators have played an important role in promoting connections and interaction. Consequently, the Dot Idea program emerged as a result of a joint effort to create a program using a design science research methodology aiming to foster new businesses and strengthen Brazil and Latin America as a hub to develop new solutions for traditional organizations. In regards to lessons learned, the Dot.health trial had some success but also experienced difficulties; these related to the relationships between startups and a hospital’s internal teams, and startups’ needs to be funded from the beginning in order to be fully dedicated to a project.

Syntheses, Structures, and Characterization of Quaternary Tellurites, Li₃MTe₄O₁₁ (M = Al, Ga, and Fe)

Lü,, Minfeng,Jo, Hongil,Oh, Seung-Jin,Lee, Suheon,Choi, Kwang-Yong,Yu, Yang,Ok, Kang Min ACS AMERICAN CHEMICAL SOCIETY 2017 Inorganic Chemistry Vol.56 No.10

<P>Three new quaternary lithium metal tellurites, Li3MTe4O11 (M = Al, Ga, and Fe), have been synthesized through hydrothermal and solid-state reactions by heating a mixture of LiOH center dot H2O, TeO2, and M2O3. The structures of the title compounds have been determined by single-crystal and powder X-ray diffraction. Li3MTe4O11 reveal three-dimensional (3D) frameworks that consist of MO6 octahedra, TeO3 trigonal pyramids, and TeO4 polyhedra. The variable coordination mode of Te4+ within the framework leads to the formation of 1D channels that host Li+ cations on both tetrahedral and octahedral sites. The bulk and grain boundary Li+ ion conductivities for a Li3FeTe4O11 pellet in open air are estimated to be 1.0 x 10(-4) and 2.7 x 10(-6) S cm(-1), respectively, at room temperature from the impedance profile analysis. A lower activation energy of 19.9 kJ mol(-1) is obtained for the system, which is similar to that of Li10GeP2S12 (24 kJ mol(-1)). Detailed characterizations such as thermal, spectroscopic, and magnetic properties for the reported materials are also reported.</P>

Litigation in Vietnamese Criminal Procedure and the Judicial Reform

Lu’o’ng Thi My Quỳnh 전남대학교 법학연구소 2014 법학논총 Vol.34 No.1

Vietnam is actively implementing judicial reform strategy to 2020. To fit the generaltrend of the world integration, including orientation to complement the legal system,one of the priorities of judicial reform in Vietnam is: “Improving the quality of theprosecutors at trial, guaranteeing democratic litigation with lawyer, defense counsel andpeople involving in the proceedings…. The judgment of the Court must be basedprimarily on the results of litigation at the trial…”. By pointing out and analyzingspecific rules of Vietnam Criminal Procedure law, the author made comments andreviews on the role of litigation in Vietnam criminal proceedings in the context ofimplementing the judicial reform strategy.

이시카와 다쿠보쿠(石川啄木)의 시 「끝없는 토론 뒤(はてしなき議論の後)」의 한ㆍ중 수용양상 비교 : 김기진과 주작인(周作人)의 경우를 중심으로

육령 ( Ling¸ Lu ) 국제비교한국학회 2020 비교한국학 Comparative Korean Studies Vol.28 No.3

이 논문은 이시카와 다쿠보쿠의 시 「끝없는 토론 뒤」(1911)의 한ㆍ중 수용양상을 고찰하는 데 초점을 맞추고 있다. 주로 한국의 김기진의 시작품 「백수의 탄식」 (1924.6), 그리고 중국의 주작인(周作人)의 시 번역 「無結果的議論之後」(1921)를 연구대상으로 삼았다. 원시의 창작배경과 의미를 분석한 다음에, 각자의 수용배경과 수용목적, 그리고 수용방법 및 영향에 대해 검토해 보았다. 그리고 다쿠보쿠 시 속의 “브나로드”에 대한 그들의 이해를 하나의 번역사건으로 인식하여 그 자체의 독자적인 의미를 고찰했다. ‘브나로드’ 운동은 국제사회에 잘 알려진 러시아의 사회운동이지만, 크로포트킨의 자서전을 통해 전파되어 전 세계의 지식인의 지적 생산물에서 끊임없이 그 영향력을 발휘했다. 이시카와 다쿠보쿠는 대역사건(大逆事件)으로 인해 죽은 일본 무정부주의자들에 대한 안타까움을 품으면서 브나로드운동을 당대의 지식인들에 대한 권고로 제시한다. 이에 창작된 것이 그의 「끝없는 토론 뒤」란 시이다. 다쿠보쿠의 이 시를 읽은 김기진은 「백수의 탄식」이란 시를 창작했다. 일본에 의해 피식민화된 조선의 현실, 특히 관동대지진 때 일어난 조선인 학살사건을 통해 느꼈던 조선 사람으로서의 무기력함에서 출발하여, 자신의 ‘생활의 예술’이라는 이념과 결합하여 프로문학자의 길을 간다는 의지도 굳히게 되었다. 그 뒤에 그는 조선의 농촌계몽운동을 적극적으로 주창했다. 주작인의 경우, 1907년부터 이미 ‘브나로드’운동과 무정부주의에 대한 글을 발표했고 노신(魯迅)과 함께 러시아문학작품을 읽고 또한 번역해서 중국에 소개했다. 그는 일본 유학 시절에 일본의 대역사건을 비롯한 사회상황과 일본문단의 변화를 유심히 지켜봤다. 그리고 다쿠보쿠의 사상과 문학적 가치에 대해서도 전반적인 지식을 가지고 있었다. 오사운동과 신문화운동이 전개됨에 따라 당시 중국의 시대적 분위기는 더욱 급진적인 방향으로 변화해 갔다. 그러나 아직 많은 청년들이 입으로만 주의를 떠들고 있고 행동으로 옮기지 못한다. 이러한 현실을 지적하면서 주작인은 1920년에 다쿠보쿠의 「끝없는 토론 뒤」를 번역했다. 이는 또한 그의 ‘브나로드’와 ‘신촌운동’에 대한 관심과 관련이 있다. ‘브나로드’에 대한 이해에 있어서, 김기진은 이를 민중에게로 간다는 것으로 이해하는데, 민속학과 문화인류학의 영향을 받은 주작인은 그것을 민간으로 간다는 것으로 이해한다. 그러면서도 그들은 20세기 초의 문학청년으로서 러시아문학에 대한 애독, 생활과 예술(문학)의 밀접한 관계를 강조하는 경향, 그리고 문학으로 사회의 개혁에 참여하려는 의지 등 많은 면에서 유사성을 지니고 있다. 이 차이점과 유사성에 대한 규명을 통해 20세기 전반기 한ㆍ중 양국의 신문학의 발전양상을 이해하는 데 도움이 되고자 한다. This paper focuses on examining the aspects of the acceptance of Takuboku’s “After an Endless Discussion” in East Asian. Especially Kim Ki-jin’s “Sigh of the White-hands” in Korea and the translation of this poem by the Chinese main author Zhou Zuoren. After analyzing the background and meaning of this poem, I reviewed the background and different purposes, and the methods and effects of acceptance. As a translation case, their various understanding of “Vnarod” in the poem is considered to have its own independent value. The “Vnarod” movement is a historic event known to the international society as Russia’s social movement, but it has been propagated through Kroportkin’s autobiography and continues to play its role in intellectual products around the world. In the case of Takuboku Ishikawa, it serves as a recommendation to intellectuals of the time, with the sorrow for the Japanese anarchists who was killed by the Japanese government Takuboku created this poem, “After an Endless Discussion”. However, Kim Ki-jin, who read Takuboku’s poem, created a poem called “Sigh of the White-hands.” Starting from the reality of Joseon, which was eroded by Japan, especially the Korean people’s helplessness felt through the massacre of Koreans during the Great East Japan Earthquake. Later, it actively promoted the rural enlightenment movement of Joseon. In the case of the Zhou Zuoren, he has already published articles on the “Vnarod” movement and anarchism since 1907, and he has been eagerly watching the social situation, including Japan’s incidents, and changes in the Japanese literary world. And he had full knowledge of Takuboku’s ideas and literary values. With the development of the student movement and the New Cultural Movement, the atmosphere of the times in China at that time bacame amore intense. Yet many young people are still only talking and not getting into action. Pointing to this reality, the author translated Takuboku’s “After the Endless Discussion” in 1920. It also has to do with his interest in ‘Vnarod’ and ‘Sinchon Movement.’ In terms of understanding ‘Vnarod’, Kim Ki-jin understands that it is going to the people, but Zhou was influenced by folklore and cultural anthropology. At the same time, they have many similarities in their fondness for Russian literature, their tendency to emphasize the close relationship between life and art (literature), and their willingness to participate in the reform of society through literature.