주강산업의 발전을 위한 제언

이필호 한국주조공학회 1996 한국주조공학회지 Vol.16 No.7

Synthesis and $SmI_{2}$-Induced Ring Expansion Reactions of Activated Cyclopyl Ketone Derivatives Containing Ester Group

이필호,이죽영,김형천,Lee, Pil Ho,Lee, Juk Yeong,Kim, Hyeong Cheon Korean Chemical Society 2000 Bulletin of the Korean Chemical Society Vol.21 No.2

이탈리아의 최근 전기통신 동향

이필호,Lee, Pil-Ho 한국전자통신연구원 1988 전자통신동향분석 Vol.3 No.2

A Facile Preparation of 2-(2-Hydroxyethyl)homoallenylsilanes Using In Situ Generated Homoallenylindium Reagent

이필호,방극찬,안효순,이구연,Lee, Pil Ho,Bang, Geuk Chan,An, Hyo Sun,Lee, Gu Yeon Korean Chemical Society 2001 Bulletin of the Korean Chemical Society Vol.22 No.12

In situ generated homoallenylindium reagents derived from the reaction of indium with 4-bromo-3-[(tri-methylsilyl) methyl]-1,2-butadiene reacted with a variety of aldehydes in DMF to produce 2-(2-hydroxy-ethyl) homoallenylsilanes at room temperatu re in good to excellent yields. 2- or 3-Hydroxybenzaldehyde that contains labile hydrogen was reacted with homoallenylindium reagent to provide the homoallenylsilanes. In the case of 4-formylbenzoic acid, the desired compound was produced in 88% yield. 4-Bromo-3-[(trimethyl-silyl) methyl]-1,2-butadiene was prepared from monoacetylation and mesylation of 2-butyn-1,4-diol, addition of trimethylsilylmethyl anion, saponification and mesylation followed by Finkelstein reaction.

A Convenient Allylation of 1,n-Dicarbonyl Compounds Using Organoindium Reagents

이필호,동서문,이구연,Lee, Pil Ho,DongSeo, Mun,Lee, Gu Yeon Korean Chemical Society 2001 Bulletin of the Korean Chemical Society Vol.22 No.12

The chemoselective reactions of 1,n-dicarbonyl compounds with allyl halides using indium metal were investigated. $\alpha-Ketoesters$ such as ethyl pyruvate, ethyl 3-methyl-2-oxobutyrate and ethyl benzoylformate reacted with a variety of allyl halides i n the presence of indium to afford hydroxy unsaturated carbonyl compounds in good to excellent yields in MeOH/HCl at $25^{\circ}C.$ For the allyl bromide, the presence of various substituents at the $\alpha$ or $\gamma$ position exhibited little effects on both the reaction rates and yields. Ethyl acetoacetate or ethyl levulinate was treated with allylindium reagent to give hydroxy unsaturated carbonyl compounds in good yield. These results mean that both reactivity and selectivity are independent of the distance between carbonyl groups. 2,3-Butanedione or 1-phenyl-1,2-propanedione reacted with allylindium to produce monoallylation product as major compound.

Regioselective Addition Reactions of the Organoindium Reagents onto α, β-Unsaturated Ketones

이필호,Hyun Kim,이구연,Dong Seomoon,Sundae Kim,Heechul Kim,Hyunseok Kim,Miae Lee,Eunkyong Shim,Seokju Lee,Misook Kim,Mijeong Han,Kwanghyun Noh,Madabhushi Sridhar 대한화학회 2004 Bulletin of the Korean Chemical Society Vol.25 No.11

Regioselectivity on the reactions of α,β-enones with organoindium such as in situ generated allylindium and allenylindium was systematically studied in the presence of TMSCl as an additive. Treatment of 2-cyclohexen- 1-one, carvone, 2-cyclohepten-1-one, and chalcone with allylindium reagent produced 1,4-addition products in good yields, while 2-cyclopenten-1-one, 2-methyl-2-cyclopenten-1-one, 4,4-dimethylcyclohexen-1-one, 3- nonen-2-one, 4-hexen-3-one, and 4-phenyl-3-buten-2-one afforded 1,2-addition products. Indium reagent derived from indium and propargyl bromide in Grignard type gave addition products in good yields, under which the successive addition of α,β-enone and TMSCl were necessary. Although organoindium reagent derived from propargyl bromide produced propargylated compound in Grignard type except 2-cyclohepten-1- one, indium reagent obtained from 1-bromo-2-butyne having γ-methyl group gave allenylated product in Barbier type.

Free Radical-mediated Ring Expansion Reactions:Endocyclic Cleavage of Cyclopropylcarbinyl Radicals

이필호,이병철,이구연,이창희,장숙복,Lee, Pil Ho,Lee, Byeong Cheol,Lee, Gu Yeon,Lee, Chang Hui,Jang, Suk Bok Korean Chemical Society 2000 Bulletin of the Korean Chemical Society Vol.21 No.6

Ring expansion reactions via endocyclic cleavage of cyclopropylcarbinyl radicals derived from the reaction of [1-benzyloxycarbonylbicyclo[n. 1.O]alk-(n+l)-yl] -1-imidazolethiocarboxylates with tributyltin hydride/AIBN proceeded to produce 3-cycloalkenecarboxylates in good yields. Benzyl (5'-phenoxypentyl) -3-cyclohepten-1 -carboxylate was obtained in 33% yield from the reaction of benzyl 5-methylenebicyclo [4. 1.0]- 1-carboxylates with 4-phenoxybutyl iodide under radical conditions. Selective cleavage of endocyclic bond in cyclopropane to the cyclohexane, results from stabilization of the resultant radical by the carbonyl groups, such as the benzyloxycarbonyl group, which lower the transition state energy for the final cyclopropane cleavage in the ring expansion.

대형 3D프린팅 부품 제작을 위한 이축 압출 스크류 헤드 기반 적층제조 시스템 개발

이필호,하태호,정민교,최준필,양창근 한국생산제조학회 2023 한국생산제조학회지 Vol.32 No.3

Large-scale material extrusion additive manufacturing is a promising alternative to the wooden mold industry, which faces challenges such as poor working conditions and an aging workforce. However, the current commercial single-screw extrusion heads have limitations owing to their weight and volume, requiring the use of expensive equipment. This study proposes the development of a twin-screw extrusion head that can be easily installed on an existing large-scale CNC milling machine, creating a prototype for additive manufacturing based on screw extrusion. The developed prototype is used to evaluate the extrusion additive manufacturing of ABS polymer composite material impregnated with glass fiber, the mechanical properties of printed specimens, the microstructure of the specimen fracture surface, and the performance of additive manufacturing shape implementation. The experiment confirmed that the proposed system achieved precision in the laminated shape and mechanical performance and could replace the wood pattern process in the existing wooden mold industry.

노인의 여가 및 자원봉사활동이 생활만족도에 미치는 상대적 영향력

이필호,조용하 한국성인교육학회 2012 Andragogy Today : International Journal of Adult & Vol.15 No.2

The purpose of this study is to investigate differences in leisure activity, volunteer service activity and life satisfaction. Data obtained from the study were statistically processed through t-test, One-Way ANOVA and Scheffe test. In addition, correlations among relevant factors were examined through correlation and regression analyses. Findings of this study can be summarized as follows. First, correlations between old people's life satisfaction and leisure activity participation were examined to find that of the leisure activities in which those people were participating, most or 56.5% were health and sport activities and that the aged persons were higher in life satisfaction when they were higher in the frequency of leisure activity participation, longer in the period of the participation and higher in leisure activity satisfaction. Second, correlations between old people's volunteer service activity participation and life satisfaction were investigated to find that of the volunteer service activities those people were participating, most or 36.9% were volunteer services at halls and nursing homes for the aged and that the people were higher in life satisfaction when they were longer in the period of the participation and higher in volunteer service activity satisfaction. Third, factors affecting old people's life satisfaction were analyzed in terms of relative predictability to find that there were statistically significant static correlations between those people's life satisfaction and their having a spouse or not, educational background, health state, standard of living, family relations, allowance, engaging in a profitable work or not, leisure activity participation and volunteer service activity participation. Fourth, those predictive factors were compared in terms of relative influence to find that old people's life satisfaction were most influenced by their participation in both volunteer service and leisure activities, followed by participation in volunteer service activity only, standard of living, health state, family relations, age, engaging in a profitable work or not and participation in leisure activity only in order. 본 연구의 목적은 **지역 거주 55세(고령자 고용촉진법 기준)이상의 노인을 대상으로 노인의 여가 및 자원봉사활동 참여형태가 생활만족에 미치는 상대적 영향력을 고찰하고 실증적으로 분석하는 데 있다. 표본선정을 위해 **시 통계연보(2009)를 모집단으로 하여 유층표집과 집락표집을 하였다. 목표 표본 수는 1000명을 설정하였으며 유효한 표본 수는 865명이다. 연구를 위한 측정도구는 생활만족도, 여가활동만족도, 자원봉사활동만족도, 여가활동참여, 자원봉사활동참여 등이다. 자료 분석방법으로는 t-test와 일원변량분석(Scheffe검증), 그리고 변인 간 관계를 알아보기 위하여 상관관계 및 회귀분석을 실시하였다. 연구결과를 요약하면 다음과 같다. 첫째, 인구학적 특성에 따른 생활만족도에서는 교육수준이 낮을수록 생활만족도가 높으며, 가족관계적 특성에서는 배우자가 있는 노인들이 없는 노인들보다 생활만족도가 높은 것으로 나타났다. 사회경제적 특성에서는 생활수준이 높을수록, 수입이 되는 일(취업여부)을 할수록, 가족의 한 달 수입이 많을수록, 여가활동과 자원봉사활동 모두 참여하고 있을 때 생활만족도가 높게 나타났다. 둘째, 노인의 생활만족도를 설명하는 관련변인들의 변수 중에서는 성별, 연령, 건강상태, 생활수준, 현재 가족관계, 수입이 되는 일 유․무 변수가 통계적으로 유의한 것으로 나타났다. 셋째, 노인의 여가 및 자원봉사활동 참여형태가 노인의 생활만족도에 미치는 상대적 영향력을 살펴보면 여가 및 자원봉사활동 모두 참여하지 않는 노인보다는 여가활동에만 참여<자원봉사활동에만 참여<자원봉사활동과 여가활동 모두 참여하는 노인들의 순으로 생활만족도가 높게 나타나 세 변수 모두 통계적으로 유의한 것으로 나타났다.

인듐을 매개로한 천연물인 Methyl 2,4,5-Tetradecatrienoate의 합성

이필호,심준환 강원대학교 기초과학연구소 2005 기초과학연구 Vol.16 No.-

  인듐을 이용한 cross-coupling 반응을 통해 Acanthosccelides obtectus의 페로몬으로부터 분리된 천연물인 methyl 2,4,5-tetradecatrienoate의 효과적인 합성법을 개발하였다. 4 mol%의 Pd(PPh3)4 존재하에서 인듐과 3-bromo-1-undecyne의 반응으로부터 얻어진 인듐 시약을 (E)-methyl 3-bromopropenoate와의 cross-coupling 반응을 통해 생성물을 좋은 수율로 얻을 수 있었다.