Pub Date : 1987-06-01DOI: 10.1016/0047-2670(87)87013-2
A. Seret, E. Gandin, A. Van De Vorst
The paramagnetism loss of nitroxide, photosensitized by eosin, was analysed in basic aqueous and micellar media using electron paramagnetic resonance (EPR) spectroscopy. In cetyltrimethylammonium bromide micelles and sodium bis(2-ethylhexyl)sulphosuccinate—n-heptane microemulsions, the paramagnetism decay curves are monoexponential. This is not the case in neat water and sodium dodecylsulphate micelles, for which more complex decays were recorded. It is concluded from flash photolysis measurements that the eosin triplet state is physically quenched by nitroxide and that the latter can be reduced by electron transfer either from the triplet state or from the semireduced form of eosin. This sequence of reactions was confirmed by experiments in micellar media and leads to an understanding of the EPR results.
{"title":"Nitroxide reduction by electron transfer from the eosin triplet state: electron paramagnetic resonance and flash photolysis studies","authors":"A. Seret, E. Gandin, A. Van De Vorst","doi":"10.1016/0047-2670(87)87013-2","DOIUrl":"10.1016/0047-2670(87)87013-2","url":null,"abstract":"<div><p>The paramagnetism loss of nitroxide, photosensitized by eosin, was analysed in basic aqueous and micellar media using electron paramagnetic resonance (EPR) spectroscopy. In cetyltrimethylammonium bromide micelles and sodium bis(2-ethylhexyl)sulphosuccinate—<em>n</em>-heptane microemulsions, the paramagnetism decay curves are monoexponential. This is not the case in neat water and sodium dodecylsulphate micelles, for which more complex decays were recorded. It is concluded from flash photolysis measurements that the eosin triplet state is physically quenched by nitroxide and that the latter can be reduced by electron transfer either from the triplet state or from the semireduced form of eosin. This sequence of reactions was confirmed by experiments in micellar media and leads to an understanding of the EPR results.</p></div>","PeriodicalId":16771,"journal":{"name":"Journal of Photochemistry","volume":"38 ","pages":"Pages 145-155"},"PeriodicalIF":0.0,"publicationDate":"1987-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0047-2670(87)87013-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85237756","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}
Pub Date : 1987-06-01DOI: 10.1016/0047-2670(87)87018-1
Guy J. Collin, George R. De Maré
The photochemical ring cleavage and ring contraction reactions of cyclic olefins are reviewed. The retro Diels-Alder processes cannot be unambiguously linked to a particular electronic state. Although there seem to be some differences between the bicycloalkane products observed in the photosensitization (triplet) and the direct photolysis (singlet) of cyclo-olefins, these differences do not warrant assignment of the formation of a given bicycloalkane to a particular electronic state. Ring contraction to the corresponding vinylcycloalkane can occur from either the triplet or the “hot” ground state. The formation of methylenecycloalkanes appears to be a reaction specific to a Rydberg singlet state of the cycloalkenes.
{"title":"Ring contraction of cyclic olefins: chemical processes specific to electronically excited states?","authors":"Guy J. Collin, George R. De Maré","doi":"10.1016/0047-2670(87)87018-1","DOIUrl":"https://doi.org/10.1016/0047-2670(87)87018-1","url":null,"abstract":"<div><p>The photochemical ring cleavage and ring contraction reactions of cyclic olefins are reviewed. The retro Diels-Alder processes cannot be unambiguously linked to a particular electronic state. Although there seem to be some differences between the bicycloalkane products observed in the photosensitization (triplet) and the direct photolysis (singlet) of cyclo-olefins, these differences do not warrant assignment of the formation of a given bicycloalkane to a particular electronic state. Ring contraction to the corresponding vinylcycloalkane can occur from either the triplet or the “hot” ground state. The formation of methylenecycloalkanes appears to be a reaction specific to a Rydberg singlet state of the cycloalkenes.</p></div>","PeriodicalId":16771,"journal":{"name":"Journal of Photochemistry","volume":"38 ","pages":"Pages 205-215"},"PeriodicalIF":0.0,"publicationDate":"1987-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0047-2670(87)87018-1","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72261014","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}
Pub Date : 1987-06-01DOI: 10.1016/0047-2670(87)87033-8
F. Wilkinson, C. Willsher, J. Bourdelande, J. Font, J. Greuges
{"title":"Photophysical evidence for intramolecular energy transfer in insoluble polymeric benzophenone (benzoylated polystyrene beads)","authors":"F. Wilkinson, C. Willsher, J. Bourdelande, J. Font, J. Greuges","doi":"10.1016/0047-2670(87)87033-8","DOIUrl":"https://doi.org/10.1016/0047-2670(87)87033-8","url":null,"abstract":"","PeriodicalId":16771,"journal":{"name":"Journal of Photochemistry","volume":"15 1","pages":"381-384"},"PeriodicalIF":0.0,"publicationDate":"1987-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73420399","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}
Pub Date : 1987-06-01DOI: 10.1016/0047-2670(87)87016-8
M. Lamotte, J. Pereyre, J. Joussot‐Dubien, R. Lapouyade
{"title":"The photolysis of pyrene and perylene in cyclohexane liquid solution from highly excited electronic states","authors":"M. Lamotte, J. Pereyre, J. Joussot‐Dubien, R. Lapouyade","doi":"10.1016/0047-2670(87)87016-8","DOIUrl":"https://doi.org/10.1016/0047-2670(87)87016-8","url":null,"abstract":"","PeriodicalId":16771,"journal":{"name":"Journal of Photochemistry","volume":"37 1","pages":"177-188"},"PeriodicalIF":0.0,"publicationDate":"1987-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91314071","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}
Pub Date : 1987-06-01DOI: 10.1016/0047-2670(87)87033-8
F. Wilkinson, C.J. Willsher, J.L. Bourdelande, J. Font, J. Greuges
{"title":"Photophysical evidence for intramolecular energy transfer in insoluble polymeric benzophenone (benzoylated polystyrene beads)","authors":"F. Wilkinson, C.J. Willsher, J.L. Bourdelande, J. Font, J. Greuges","doi":"10.1016/0047-2670(87)87033-8","DOIUrl":"https://doi.org/10.1016/0047-2670(87)87033-8","url":null,"abstract":"","PeriodicalId":16771,"journal":{"name":"Journal of Photochemistry","volume":"38 ","pages":"Pages 381-384"},"PeriodicalIF":0.0,"publicationDate":"1987-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0047-2670(87)87033-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72261010","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}
Pub Date : 1987-06-01DOI: 10.1016/0047-2670(87)87029-6
Michel Julliard, Alain Luciani, Jean-Louis Chevalier, Georges Cecchi, Eugène Ucciani
The conjugation of methyl 9,12-octadecadienoate (DH) is a reaction of industrial interest. It has been photochemically performed with iodine as photosensitizer (λ=520nm). The reaction is a radical chain process which is inhibited by galvinoxyl, the overall quantum yield decreasing from 1.9 to 1.3 with the irradiation time. The rate is given by the empirical expression k [i]0.56 [ DH]1.22 [I2]0.40 where i is the light intensity. The reaction leads to a mixture of methyl 9,11-octadecadienoate and methyl 10,12-octadecadienoate with E,E:Z,E:Z,Z in the molar ratio of 0.72:0.26:0.02 in 80% yield.
This study illustrates the possibility of applying solar radiation to an industrial process.
{"title":"Photosensitized conjugation of methyl 9,12-octadecadienoate","authors":"Michel Julliard, Alain Luciani, Jean-Louis Chevalier, Georges Cecchi, Eugène Ucciani","doi":"10.1016/0047-2670(87)87029-6","DOIUrl":"https://doi.org/10.1016/0047-2670(87)87029-6","url":null,"abstract":"<div><p>The conjugation of methyl 9,12-octadecadienoate (DH) is a reaction of industrial interest. It has been photochemically performed with iodine as photosensitizer (λ=520nm). The reaction is a radical chain process which is inhibited by galvinoxyl, the overall quantum yield decreasing from 1.9 to 1.3 with the irradiation time. The rate is given by the empirical expression <em>k</em> [<em>i</em>]<sup>0.56</sup> [ DH]<sup>1.22</sup> [I<sub>2</sub>]<sup>0.40</sup> where <em>i</em> is the light intensity. The reaction leads to a mixture of methyl 9,11-octadecadienoate and methyl 10,12-octadecadienoate with <em>E,E</em>:<em>Z,E</em>:<em>Z,Z</em> in the molar ratio of 0.72:0.26:0.02 in 80% yield.</p><p>This study illustrates the possibility of applying solar radiation to an industrial process.</p></div>","PeriodicalId":16771,"journal":{"name":"Journal of Photochemistry","volume":"38 ","pages":"Pages 345-355"},"PeriodicalIF":0.0,"publicationDate":"1987-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0047-2670(87)87029-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72260982","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}
Pub Date : 1987-06-01DOI: 10.1016/0047-2670(87)87034-X
J. Mayer, M. Szadkowska-Nicze, J. Kroh
The fluorescence lifetime-temperature dependences for naphthalene and pyrene in 3-methylpentane were investigated in the temperature range 92 - 298 K using Čerenkov light as the source of photochemical excitation. The results are explained in terms of temperature-dependent intersystem crossing from S1 to the adjacent triplet levels.
{"title":"Low temperature fluorescence lifetime of aromatic solutes in 3-methylpentane: investigation using Čerenkov radiation","authors":"J. Mayer, M. Szadkowska-Nicze, J. Kroh","doi":"10.1016/0047-2670(87)87034-X","DOIUrl":"https://doi.org/10.1016/0047-2670(87)87034-X","url":null,"abstract":"<div><p>The fluorescence lifetime-temperature dependences for naphthalene and pyrene in 3-methylpentane were investigated in the temperature range 92 - 298 K using Čerenkov light as the source of photochemical excitation. The results are explained in terms of temperature-dependent intersystem crossing from S<sub>1</sub> to the adjacent triplet levels.</p></div>","PeriodicalId":16771,"journal":{"name":"Journal of Photochemistry","volume":"38 ","pages":"Pages 385-389"},"PeriodicalIF":0.0,"publicationDate":"1987-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0047-2670(87)87034-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72261009","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}
Pub Date : 1987-06-01DOI: 10.1016/0047-2670(87)87020-X
D. Birch, A. Dutch, R. Imhof, B. Nadolski, I. Soutar
{"title":"The effect of transient quenching on the excimer kinetics of 2,5-diphenyloxazole","authors":"D. Birch, A. Dutch, R. Imhof, B. Nadolski, I. Soutar","doi":"10.1016/0047-2670(87)87020-X","DOIUrl":"https://doi.org/10.1016/0047-2670(87)87020-X","url":null,"abstract":"","PeriodicalId":16771,"journal":{"name":"Journal of Photochemistry","volume":"100 1","pages":"239-254"},"PeriodicalIF":0.0,"publicationDate":"1987-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77566054","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}
Pub Date : 1987-06-01DOI: 10.1016/0047-2670(87)87003-X
L.F. Phillips
Molar absorption coefficients of NONH2 have been measured for bands at 285 nm, 365 nm and 550 nm, and the bands assigned to the tautomeric species HNNOH, NH2NO and HNNHO respectively. Solutions of NO in liquid ammonia have an absorption band at 425 nm which is assigned to a charge transfer complex of NO with NH3. It is suggested that coloured solutions of NONH2 and NO in liquid ammonia may contribute to the colours observed in the atmosphere of Jupiter.
{"title":"Absorption spectra of NONH2 isomers and NO in liquid ammonia solution: possible implications for Jupiter","authors":"L.F. Phillips","doi":"10.1016/0047-2670(87)87003-X","DOIUrl":"10.1016/0047-2670(87)87003-X","url":null,"abstract":"<div><p>Molar absorption coefficients of NONH<sub>2</sub> have been measured for bands at 285 nm, 365 nm and 550 nm, and the bands assigned to the tautomeric species HNNOH, NH<sub>2</sub>NO and HNNHO respectively. Solutions of NO in liquid ammonia have an absorption band at 425 nm which is assigned to a charge transfer complex of NO with NH<sub>3</sub>. It is suggested that coloured solutions of NONH<sub>2</sub> and NO in liquid ammonia may contribute to the colours observed in the atmosphere of Jupiter.</p></div>","PeriodicalId":16771,"journal":{"name":"Journal of Photochemistry","volume":"38 ","pages":"Pages 35-41"},"PeriodicalIF":0.0,"publicationDate":"1987-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0047-2670(87)87003-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78913578","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}
Pub Date : 1987-06-01DOI: 10.1016/0047-2670(87)87028-4
E. Lipczynska‐kochany, J. Kochany
{"title":"Chemistry of hydroxamic acid XII: Photochemistry of N-phenylbenzenecarbo-hydroxamic acid—studies on the mechanism of reaction","authors":"E. Lipczynska‐kochany, J. Kochany","doi":"10.1016/0047-2670(87)87028-4","DOIUrl":"https://doi.org/10.1016/0047-2670(87)87028-4","url":null,"abstract":"","PeriodicalId":16771,"journal":{"name":"Journal of Photochemistry","volume":"32 1","pages":"331-343"},"PeriodicalIF":0.0,"publicationDate":"1987-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83099332","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}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号