Experimental study was performed on convective heat transfer in annular passage in order to clarify the condition for occurrence of turbulent to laminar reverse transition. Examined Reynolds number ranged from 6000 to 10000 and nondimensional heating parameter q^+_m from 0.2×10^ to 4.5×10^ . Although most of experimental conditions in terms of nondimensional heating parameter satisfied the criteria proposed so far for circular tube flows, no definite laminarization was observed in the present study. At the region of fully developed heating, however, Nusselt number shows maximum 10% drop from the well known heat transfer correlation of variable flow properties, and rather agrees with the correlation proposed by S. Fuji et al.
{"title":"環状流路内の層流化現象に関する研究 : 第２報 内菅加熱の場合","authors":"鳥居 修一, 清水 昭比古, 修 長谷川","doi":"10.15017/17656","DOIUrl":"https://doi.org/10.15017/17656","url":null,"abstract":"Experimental study was performed on convective heat transfer in annular passage in order to clarify the condition for occurrence of turbulent to laminar reverse transition. Examined Reynolds number ranged from 6000 to 10000 and nondimensional heating parameter q^+_m from 0.2×10^ to 4.5×10^ . Although most of experimental conditions in terms of nondimensional heating parameter satisfied the criteria proposed so far for circular tube flows, no definite laminarization was observed in the present study. At the region of fully developed heating, however, Nusselt number shows maximum 10% drop from the well known heat transfer correlation of variable flow properties, and rather agrees with the correlation proposed by S. Fuji et al.","PeriodicalId":11722,"journal":{"name":"Engineering sciences reports, Kyushu University","volume":"376 1","pages":"51-56"},"PeriodicalIF":0.0,"publicationDate":"1986-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76628367","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Starting from the partially-optical active 7-methoxybicyclo[3.2.0]hepta-3,6-dien-2-one, a photoisomer of 2-methoxytropone obtained from the B-cyclodextrin inclusion complex, bis(dehydroxy)xanthocidin methyl ester was synthesized. In 1978, we found2' a photoisomerization of troponoids under a-and P-cyclodextrin (CDX)-included conditions to give bicyclo(3.2.0]hepta-3,6-dien-2-ones with a remarkable rate enhancement and with much improved yields for proto-photoisomers in various dispersion media. The photoproducts derived from tropolone (la) and 2-methoxytropone (lb) were optically active, and by using these optically active specimens, we have carried out a mechanistic investigation of the "antara-antara"-3, 3-sigmatropy;3' the thermolysis of optically active 1-methoxybicyclo[3.2.0]hepta-3,6-dien-2-one (2) to optically active 3-methoxybicyclo[ 3.2.0 ]hepta-3, 6-dien-2-one (3), ruled out an involvement of radical intermediate.`•5•6) Obviously, the photoproduct (2) is good starting material for polysubstituted cyclopentane derivatives, and by this mean we have now synthesized a dialkyl derivative (4) of sarkomycin (B)7' which can be, in same time, designated as a bis(dehydroxyl) derivative of xanthocidin8' from 7-methoxybicyclo[3.2.0Ihepta-3, 6-dien-2-one (5). The findings will be described in this paper. An a-methylenecyclopentanone antibiotic, xanthocidin (A) was first isolated from a Streptomlces species, IVo.51--4by Asahi et al.8' and its racemic form has been synthesized by Smith9' via the key intermediate, bis(dehydroxy)-4, 5-dehydroxanthocidin (C). The above mentioned readines$ in furnishing the cyclopentene synthons prompted us to carry out the experiments on the synthesis of this methylene cyclopentanone relative, methyl ester of bis(dehydroxyl) derivative (4) of A'O' as follows. Prolonged irradiation of lb under the B-CDX-inclusion conditions in cyclohexane afforded optically active 5'i' via the proto-photoisomer (2),i2' 1-methoxyl isomer, in 470/o yield with 550/o enantiomeric excess. Optical activities of these compounds were determined by derivation to 3oxocyclopentaneacetic acid (6). By the Grignard reaction of 5 with isopropylmagnesium bromide and subsequent quenching of the resultant magnesium enolate with methyl iodide, 4-isopropyl-7-methoxy-3-methylbicyclo[3.2.0]hept-6-en-2-one (7) was obtained in 630/o yield in a one-pot operation. The direction of the attack of bulky isopropyl group to the *Department of Molecular Engineering -20Partial Asymmertric Synthesis of Xanthocidin Derivatives from Troponoids
{"title":"Synthetic Photochemistry. XXXV. A Synthesis of Bis (dehydroxy) xanthocidin Methyl Ester from the Partially Optical Active Photoisomer of β-Cyclodextrin-included 2-Methoxytropone","authors":"A. Mori, Yasuhiro Shimada, H. Takeshita","doi":"10.15017/17651","DOIUrl":"https://doi.org/10.15017/17651","url":null,"abstract":"Starting from the partially-optical active 7-methoxybicyclo[3.2.0]hepta-3,6-dien-2-one, a photoisomer of 2-methoxytropone obtained from the B-cyclodextrin inclusion complex, bis(dehydroxy)xanthocidin methyl ester was synthesized. In 1978, we found2' a photoisomerization of troponoids under a-and P-cyclodextrin (CDX)-included conditions to give bicyclo(3.2.0]hepta-3,6-dien-2-ones with a remarkable rate enhancement and with much improved yields for proto-photoisomers in various dispersion media. The photoproducts derived from tropolone (la) and 2-methoxytropone (lb) were optically active, and by using these optically active specimens, we have carried out a mechanistic investigation of the \"antara-antara\"-3, 3-sigmatropy;3' the thermolysis of optically active 1-methoxybicyclo[3.2.0]hepta-3,6-dien-2-one (2) to optically active 3-methoxybicyclo[ 3.2.0 ]hepta-3, 6-dien-2-one (3), ruled out an involvement of radical intermediate.`•5•6) Obviously, the photoproduct (2) is good starting material for polysubstituted cyclopentane derivatives, and by this mean we have now synthesized a dialkyl derivative (4) of sarkomycin (B)7' which can be, in same time, designated as a bis(dehydroxyl) derivative of xanthocidin8' from 7-methoxybicyclo[3.2.0Ihepta-3, 6-dien-2-one (5). The findings will be described in this paper. An a-methylenecyclopentanone antibiotic, xanthocidin (A) was first isolated from a Streptomlces species, IVo.51--4by Asahi et al.8' and its racemic form has been synthesized by Smith9' via the key intermediate, bis(dehydroxy)-4, 5-dehydroxanthocidin (C). The above mentioned readines$ in furnishing the cyclopentene synthons prompted us to carry out the experiments on the synthesis of this methylene cyclopentanone relative, methyl ester of bis(dehydroxyl) derivative (4) of A'O' as follows. Prolonged irradiation of lb under the B-CDX-inclusion conditions in cyclohexane afforded optically active 5'i' via the proto-photoisomer (2),i2' 1-methoxyl isomer, in 470/o yield with 550/o enantiomeric excess. Optical activities of these compounds were determined by derivation to 3oxocyclopentaneacetic acid (6). By the Grignard reaction of 5 with isopropylmagnesium bromide and subsequent quenching of the resultant magnesium enolate with methyl iodide, 4-isopropyl-7-methoxy-3-methylbicyclo[3.2.0]hept-6-en-2-one (7) was obtained in 630/o yield in a one-pot operation. The direction of the attack of bulky isopropyl group to the *Department of Molecular Engineering -20Partial Asymmertric Synthesis of Xanthocidin Derivatives from Troponoids","PeriodicalId":11722,"journal":{"name":"Engineering sciences reports, Kyushu University","volume":"3 1","pages":"19-24"},"PeriodicalIF":0.0,"publicationDate":"1986-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84961726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Numerical analysis has been carried out to explain and predict the choking phenomena and the occurence of a shock wave in subsonic and supersonic Faraday type MHD generators, using a quasi-one-dimensional theory. This study is intended to provide one of data bases for a large-scale MHD generator. The steady one-dimensional conservation equations, coupled with the Ampere's law and the generalized Ohm's law, are solved. It has been shown that, in the case of a divergent channel and that a loading factor is constant, the limiting length of channel for choking decreases with an increase in an interaction parameter. A shock wave appears in a divergent channel for a certain range of the interaction parameter. The minimum value increases with an increase in the loading factor and with a decrease in the friction coefficient, but it is almost independent of the inlet Mach number of the channel. On the other hand, the maximum value increases with increases in the loading factor and in the inlet Mach number, but it is almost independent of the friction coefficient.
{"title":"ファラデー型 MHD 発電チャネル内の流動特性に関する数値解析","authors":"青木 俊之, 松尾 一泰, 近藤 信昭, 池田 利弘","doi":"10.15017/17625","DOIUrl":"https://doi.org/10.15017/17625","url":null,"abstract":"Numerical analysis has been carried out to explain and predict the choking phenomena and the occurence of a shock wave in subsonic and supersonic Faraday type MHD generators, using a quasi-one-dimensional theory. This study is intended to provide one of data bases for a large-scale MHD generator. The steady one-dimensional conservation equations, coupled with the Ampere's law and the generalized Ohm's law, are solved. It has been shown that, in the case of a divergent channel and that a loading factor is constant, the limiting length of channel for choking decreases with an increase in an interaction parameter. A shock wave appears in a divergent channel for a certain range of the interaction parameter. The minimum value increases with an increase in the loading factor and with a decrease in the friction coefficient, but it is almost independent of the inlet Mach number of the channel. On the other hand, the maximum value increases with increases in the loading factor and in the inlet Mach number, but it is almost independent of the friction coefficient.","PeriodicalId":11722,"journal":{"name":"Engineering sciences reports, Kyushu University","volume":"2 1","pages":"47-53"},"PeriodicalIF":0.0,"publicationDate":"1985-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81651023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Koya Okaishi, T. Hatsui, H. Takeshita, 岡石 幸也, 初井 敏英, 竹下 齊
Methyl 2,4-dioxopentanoate and myrcene smoothly afforded the photoadducts by irradiation with a high-pressure mercury lamp. The (2+2) rr adducts were selectively resulted from the conjugated double bond moiety. Reductive cyclization of the adduct afforded cycloneryl derivatives, whose further chemical conversion were carried out. Previously we have accomplished total syntheses of protoilludenes2' and some elemenoid sesquiterpenoids3' by means of the photocycloaddition of enolized B-diketone with appropriate olefins. Particularly, taking the advantage that the conjugated olefins are capable of forming photocycloadducts with 2,4-Dioxopentanoate (1), 3'`' we have carried out the photocycloaddition with isoprene (A) to efficiently construct the Cio-frameworks3•5' which were convertible to the correct head-to-tail monoterpenoid
{"title":"Synthetic Photochemistry. XXXI. The Cycloaddition Reaction of Myrcene with 2,4-Dioxopentanoate : A Facile Synthesis of a Versatile Intermediate for Cycloneryl Derivatives","authors":"Koya Okaishi, T. Hatsui, H. Takeshita, 岡石 幸也, 初井 敏英, 竹下 齊","doi":"10.15017/17621","DOIUrl":"https://doi.org/10.15017/17621","url":null,"abstract":"Methyl 2,4-dioxopentanoate and myrcene smoothly afforded the photoadducts by irradiation with a high-pressure mercury lamp. The (2+2) rr adducts were selectively resulted from the conjugated double bond moiety. Reductive cyclization of the adduct afforded cycloneryl derivatives, whose further chemical conversion were carried out. Previously we have accomplished total syntheses of protoilludenes2' and some elemenoid sesquiterpenoids3' by means of the photocycloaddition of enolized B-diketone with appropriate olefins. Particularly, taking the advantage that the conjugated olefins are capable of forming photocycloadducts with 2,4-Dioxopentanoate (1), 3'`' we have carried out the photocycloaddition with isoprene (A) to efficiently construct the Cio-frameworks3•5' which were convertible to the correct head-to-tail monoterpenoid <iridoids) and sesquiterpenoid (elemenoids) skeleton. Thus, the new way of versatile Cs-homologation for the terpenoid 2 + hv H 02Me 1 3 02Me + 02Me 4 + 5","PeriodicalId":11722,"journal":{"name":"Engineering sciences reports, Kyushu University","volume":"20 1","pages":"21-25"},"PeriodicalIF":0.0,"publicationDate":"1985-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82361866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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