Relevant bibliographies by topics / Photochemical processes

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'Photochemical processes'

Author: Grafiati
Published: 4 June 2021
Last updated: 31 January 2023

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Journal articles on the topic "Photochemical processes"

1

Melchiorre, Paolo. "Introduction: Photochemical Catalytic Processes." Chemical Reviews 122, no. 2 (January 26, 2022): 1483–84. http://dx.doi.org/10.1021/acs.chemrev.1c00993.

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Reuther, A., A. Laubereau, and D. N. Nikogosyan. "Primary Photochemical Processes in Water." Journal of Physical Chemistry 100, no. 42 (January 1996): 16794–800. http://dx.doi.org/10.1021/jp961462v.

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Hrdlovic, Pavol. "Photochemical Reactions and Photophysical Processes." Polymer News 30, no. 12 (December 2005): 380–84. http://dx.doi.org/10.1080/00323910500402870.

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Hrdlovič, Pavol. "Photochemical Reactions and Photophysical Processes." Polymer News 30, no. 3 (April 2005): 86–89. http://dx.doi.org/10.1080/00323910500459029.

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Stroyuk, O. L., N. S. Andryushina, S. Ya Kuchmy, and V. D. Pokhodenko. "Photochemical Processes Involving Graphene Oxide." Theoretical and Experimental Chemistry 51, no. 1 (March 2015): 1–29. http://dx.doi.org/10.1007/s11237-015-9393-y.

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Legrini, O., E. Oliveros, and A. M. Braun. "Photochemical processes for water treatment." Chemical Reviews 93, no. 2 (March 1993): 671–98. http://dx.doi.org/10.1021/cr00018a003.

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Young, Douglas D., and Alexander Deiters. "Photochemical control of biological processes." Org. Biomol. Chem. 5, no. 7 (2007): 999–1005. http://dx.doi.org/10.1039/b616410m.

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Frei, H., and G. C. Pimentel. "Infrared Induced Photochemical Processes in Matrices." Annual Review of Physical Chemistry 36, no. 1 (October 1985): 491–524. http://dx.doi.org/10.1146/annurev.pc.36.100185.002423.

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Song, Pill-Soon. "Photochemical Processes in Organized Molecular Systems." Photochemistry and Photobiology 56, no. 2 (August 1992): 285. http://dx.doi.org/10.1111/j.1751-1097.1992.tb02160.x.

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Yilmaz, Gorkem, and Yusuf Yagci. "New Photochemical Processes for Macromolecular Syntheses." Journal of Photopolymer Science and Technology 29, no. 1 (2016): 91–98. http://dx.doi.org/10.2494/photopolymer.29.91.

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Dissertations / Theses on the topic "Photochemical processes"

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Cuadros, Huertas Sara. "Exploiting Organocatalysis in Photochemical Processes." Doctoral thesis, Universitat Rovira i Virgili, 2019. http://hdl.handle.net/10803/668446.

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El treball descrit en aquesta dissertació es centra en la implementació d’estratègies organocatalítiques per superar les limitacions de processos fotoquímics establerts. Específicament, dues transformacions impulsades per la llum han estat estudiades: (i) la fotoenolizació de 2-alquilbenzofenones per accedir a intermedis enòlics transitoris (fotoenols), i (ii) la ruptura homolítica fotoinduïda de derivats ditiocarbonílics per produir radicals. Per un costat, el procés de fotoenolizació acoblat amb la reactivitat de tipus Diels-Alder (seqüència fotoenolizació/ Diels-Alder) és una reacció fotoquímica històrica amb aplicacions conegudes en síntesi total. Malgrat això, una variant asimètrica d’aquest procés no ha estat encara reportada. Els Capítols II i III demostren com l’organocatàlisi asimètrica proporciona eines simples i efectives per fer participar a les espècies fotoenòliques en processos de tipus Diels-Alder i aldòlics altament estereoselectius. Per un altre costat, la ruptura fotolítica de espècies ditiocarboníliques capaces d’absorbir la llum visible, és un mètode conegut per la generació de radicals sota condicions suaus de reacció. Aquesta tecnologia fa ús de quantitats estequiomètriques de compostos ditiocarbonílics fàcilment accessibles. Encara que aquesta estratègia ha millorat considerablement les condicions per accedir a la reactivitat de tipus radicalària, aquesta requereix la síntesi prèvia de compostos que continguin la funcionalitat ditiocarbonílica. El Capítol IV detalla com aquest mètode de generació de radicals pot ser realitzat catalíticament, mitjançant el disseny d’un catalitzador
El trabajo descrito en esta disertación se centra en la implementación de estrategias organocatalíticas para superar las limitaciones de procesos fotoquímicos establecidos. Específicamente, dos transformaciones promovidas por la luz han sido estudiadas: (i) la fotoenolización de 2-alquilbenzofenonas para acceder intermedios enólicos transitorios (fotoenoles), y (ii) la ruptura homolítica fotoinducida de derivados ditiocarbonílicos para producir radicales. Por un lado, el proceso de fotoenolización acoplado con la reactividad de tipo Diels-Alder (secuencia fotoenolización/ Diels-Alder) es una histórica reacción fotoquímica con aplicaciones conocidas en síntesis total. Sin embargo, una variante asimétrica de este proceso no ha sido reportada. Los Capítulos II y III demuestran cómo la organocatálisis asimétrica proporciona herramientas simples y efectivas para hacer participar a las especies fotoenólicas en procesos de tipo Diels-Alder y aldólicos altamente esteroselectivos. Por otro lado, la ruptura fotolítica de especies ditiocarbonílicas capaces de absorber luz visible, es un conocido método para la generación de radicales bajo condiciones suaves de reacción. Esta tecnología hace uso de cantidades estequiométricas de compuestos ditiocarbonílicos fácilmente accesibles. Aunque esta estrategia ha mejorado considerablemente las condiciones para acceder a la reactividad de tipo radicalaria, ésta requiere la síntesis previa de compuestos que contentan la funcionalidad ditiocarbonílica.
The work described in this dissertation focuses on the implementation of organocatalytic strategies to overcome limitations of established photochemical processes. Specifically, two known light-driven transformations have been studied: (i) the photoenolization of 2-alkyl-benzophenones to access transient enol-intermediates (photoenols), and (ii) the photoinduced homolytic cleavage of stoichiometric dithiocarbonyl derivatives to produce radicals. On the one hand, the photoenolization process coupled with classical Diels-Alder chemistry (photoenolization/Diels- Alder sequence) is an historical photochemical reaction with known applications in total synthesis. However, an asymmetric catalytic variant of this light-driven transformation has remained elusive over the years. Chapter II and Chapter III demonstrate how asymmetric organocatalysis provides simple but effective catalytic tools to engage photoenols in highly stereoselective Diels-Alder and Aldol-type processes, respectively. On the other hand, the photolytic cleavage of visible-light-absorbing dithiocarbonyl-based compounds is a known effective method for the mild generation of radicals. This technology uses stoichiometric amounts of easy-to make dithiocarbonyl-based substrates, capable of triggering the formation of open-shell intermediates upon direct light-excitation. Although this strategy has greatly enhanced the conditions to access radical-type reactivity, it still relies on purposely designed stoichiometric reagents.
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Buzzetti, Luca. "Photochemical Strategies for Carbon–Carbon Bond Forming Processes." Doctoral thesis, Universitat Rovira i Virgili, 2018. http://hdl.handle.net/10803/668971.

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La capacitat de generar intermedis radicalaris, sota condicions suaus, ha portat a l'emergent camp de la catàlisi fotoredox al desenvolupament de noves transformacions. Tradicionalment, aquesta es basa en l'ús d'un fotocatalitzador, que absorbeix eficientment llum i indueix una transferència simple d'electrons (SET). No obstant això, la reactivitat química de les molècules excitades electrònicament difereix fonamentalment de les que es troben en el seu estat fonamental. Una molècula en estat excitat és alhora una millor donant i acceptora d'electrons que en el seu estat fonamental i es comporta respectivament com una millor reductora i una millor oxidant. El principal objectiu científic d'aquesta tesi doctoral ha estat investigar i comprendre la reactivitat de l'estat excitat d'algunes molècules orgàniques per desenvolupar nous processos fotoquímics de formació d'enllaços C-C. Per aconseguir aquest objectiu, s'ha combinat diferents eines de la química orgànica. En els primers projectes (discutits en els capítols III i IV), la fusió de la organocatàlisi i la fotoquímica han permès la funcionalització asimètrica directa en la posició β d’enals, desencadenada per l'excitació amb llum visible de sals de Imini quirals formades in situ. A la segona part d'aquests estudis doctorals (discutit en el capítol V), s'ha explotat les propietats de l'estat excitat de 4-alquil-1,4-dihidropiridines (alquil-DHP) en combinació amb la catàlisi de metalls de transició pel desenvolupament de catalitzadors de níquel en reaccions radicalàries d'acoblament creuat.
La capacidad de generar intermedios radicalarios, bajo condiciones suaves, ha llevado al emergente campo de la catálisis fotoredox al desarrollo de nuevas transformaciones. Tradicionalmente, esta se basa en el uso de un fotocatalizador, que absorbe eficientemente luz e induce una transferencia simple de electrones (SET). Sin embargo, la reactividad química de las moléculas excitadas electrónicamente difiere fundamentalmente de las que se encuentran en su estado fundamental. Una molécula en estado excitado es a la vez una mejor donante y aceptora de electrones que en su estado fundamental y se comporta respectivamente como una mejor reductora y una mejor oxidante. El principal objetivo científico de esta tesis doctoral ha sido investigar y comprender la reactividad del estado excitado de algunas moléculas orgánicas para desarrollar nuevos procesos fotoquímicos de formación de enlaces C-C. Para lograr este objetivo, se han combinado diferentes herramientas de la química orgánica. En los primeros proyectos (discutidos en los Capítulos III y IV), la fusión de la organocatálisis y la fotoquímica han permitido la funcionalización asimétrica directa en la posición β de enales, desencadenada por la excitación con luz visible de sales de iminio quirales formadas in situ. En la segunda parte de estos estudios doctorales (discutido en el Capítulo V), se ha explotado las propiedades del estado excitado de 4-alquil-1,4-dihidropiridinas (alquil-DHP) en combinación con la catálisis de metales de transición para el desarrollo de catalizadores de níquel en reacciones radicalarias de acoplamiento cruzado.
The emerging field of photoredox catalysis has led to the development of new transformations due to the ability to generate radical intermediates under mild conditions. Traditionally, this relies on the use of a photocatalyst, which efficiently absorbs light and induces a single electron transfer (SET). However, the chemical reactivity of electronically excited molecules differs fundamentally from that in the ground state. An excited-state molecule is both a better electron donor and a better electron acceptor than in the ground state and behaves respectively as a better reductant and a better oxidant. The main scientific objective of this doctoral research was to investigate and understand the excited-state reactivity of some organic molecules to develop novel photochemical C–C bond-forming processes. In order to achieve this goal, different tools of organic chemistry were combined. In the first projects (discussed in Chapter III and IV), the merger of organocatalysis and photochemistry enabled the direct asymmetric β-functionalization of enals triggered by the visible-light excitation of in situ formed chiral iminium salts. In the second part of the PhD studies (discussed in Chapter V), the excited-state properties of 4-alkyl-1,4-dihydropyridines (alkyl-DHP) were exploited in combination with transition metal catalysis for the development of nickel-catalyzed radical cross-couplings.
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Raybone, D. "Chemiluminescent and photochemical processes in the gas phase." Thesis, University of Manchester, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383197.

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Sutton, Paul David. "Studies in infrared multiple photon excitations." Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.291598.

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Alandini, Nurtalya. "1,4-Dihydropyridines as Versatile Reagents in Photochemical Carbon-Carbon Bond-Forming Processes." Doctoral thesis, Universitat Rovira i Virgili, 2020. http://hdl.handle.net/10803/669606.

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Les transformacions fotoquímiques es basen en la capacitat de molècules o catalitzadors orgànics d’absorbir llum i arribar als estats electrònicament excitats. Atès que les propietats físiques i químiques de les molècules en estat excitat difereixen significativament de l'estat fonamental, la química intervinguda per la llum pot oferir nous patrons interessants de reactivitat que no estan disponibles amb l'activació tèrmica. L’objectiu principal d’aquests estudis de doctorat va ser implementar estratègies fotoquímiques adequades per desenvolupar transformacions sintètiques útils no assolibles mitjançant processos tèrmics ja coneguts. En particular, he pogut investigar i explotar la capacitat única de les 4-substit-1,4-dihidropiridines (DHPs) per formar radicals de carboni centrats en condicions suaus. En el primer projecte (capítol III), es van utilitzar 4-alquil-1,4-dihidropiridines (alquil-DHPs) com a precursors del radical alquil en l'alquilació enantioselectiva d’enals desencadenada per l'excitació amb llum visible de sals d’iminium quirals generades in situ. En la segona part d’aquests estudis de doctorat (analitzats al capítol IV), es van emprar 4-carbamoil-1,4-dihidropiridines (carbamoil-DHP) com a font de radicals de carbamoil i es van aplicar en reaccions d’acoblament creuat de radicals catalitzats amb níquel per a la síntesi d’una àmplia gamma de (hetero) aril amides.
Las reacciones fotoquímicas se basan en la capacidad de moléculas orgánicas o catalizadores para absorber luz y alcanzar a un estado electrónicamente excitado. Dado que tanto las propiedades químicas como físicas de las moléculas en su estado excitado se diferencian de aquellas en su estado fundamental, la fotoquímica puede ofrecer acceso a interesante nueva reactividad no disponible por la vía térmica. El principal objetivo de esta tesis doctoral fue la implementación de estrategias fotoquímicas para el desarrollo de reacciones sintéticamente útiles no accesibles mediante el empleo de métodos térmicos ya establecidos. En particular, la investigación y explotación de la capacidad única de las 1,4-dihidropiridinas-4-substituidas (DHPs) para formar radicales de tipo carbono usando condiciones suaves. En el primer proyecto, 1,4-dihidropiridinas-4-alquilo (DHP-alquilo) se emplearon como precursores de radicales para la alquilación enantioselectiva de enales desencadenada por excitación mediante luz visible de una sal de iminio quiral formada in situ. En la segunda parte de la tesis doctoral (desarrollada en el capítulo 4), 1,4-dihidropiridinas-4-carbamoil (DHP-carbamoil) fueron empleadas como fuente de radicales de tipo carbamoil y aplicadas en reacciones de acoplamiento de radicales catalizadas por niquel para la síntesis de un amplio rango de (hetero)aril amidas.
Photochemical transformations rely on the ability of organic molecules or catalysts to absorb light and reach the electronically excited states. Since the chemical and physical properties of excited-state molecules significantly differ from the ground state, light-mediated chemistry can offer interesting new reactivity patterns that are unavailable under thermal activation. The main objective of this doctoral studies was to implement photochemical strategies suitable for developing useful synthetic transformations not achievable using established thermal approaches. In particular, I investigated and exploited the unique ability of 4-substituted-1,4-dihydropyridines (DHPs) to form carbon-centered radicals under mild conditions. In the first project (Chapter III), 4-alkyl-1,4-dihydropyridines (alkyl-DHPs) were employed as alkyl radical precursors in the enantioselective alkylation of enals triggered by the visible-light excitation of in situ generated chiral iminium salts. In the second part of the doctoral studies (discussed in Chapter IV), 4-carbamoyl-1,4-dihydropyridines (carbamoyl-DHP) were employed as carbamoyl radical sources and applied in nickel-catalyzed radical cross-coupling reactions for the synthesis of a wide range of (hetero)aryl amides.
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Filippini, Giacomo. "Development of radical processes triggered by the photochemical activity of transient organic intermediates." Doctoral thesis, Universitat Rovira i Virgili, 2017. http://hdl.handle.net/10803/461090.

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La química desenvolupada durant la meva tesi doctoral ha estat impulsada per la capacitat d'intermedis rics en electrons (anions fenolat i enamines quirals), generats transitòriament a partir de precursors fotoquímicament inactius (fenols i aldèhids), per arribar directament a un estat electrònicament excitat després de l'absorció de llum i, posteriorment, promovent la formació d'espècies radicalàries reactives a partir dels iodurs d'alquil adequats. En les transformacions estudiades, la formació dels radicals és a través de l'escissió reductora de l'enllaç carboni-iode del precursor de iodur d'alquil mitjançant mecanismes de transferència d'un sol electró (SET). Inicialment, he desenvolupat un nou enfocament per a la perfluoroalquilació fotoquímica directa de fenols substituïts. L'ús de llum visible simple, sense la necessitat de cap fotocatalitzador o iniciador de radicals, pot promoure la perfluoroalquilació o trifluorometilació aromàtica de fenols a temperatura ambient. En un segon projecte, he desenvolupat una nova metodologia per a la metilació o bencilació en α d'aldèhids mitjançant la fotoorganocatálisi. En aquest cas, la reacció es produeix en absència de catalitzadors fotoredox externs, i els compostos desitjats s'obtenen amb bons rendiments aïllats i elevada enantioselectivitat.
La química desarrollada durante mi tesis doctoral ha sido impulsada por la capacidad de intermedios ricos en electrones (aniones fenolato y enaminas quirales), generados transitoriamente a partir de precursores fotoquímicamente inactivos (fenoles y aldehídos), para alcanzar directamente un estado electrónicamente excitado tras la absorción de luz y, posteriormente, promover la formación de especies radicalarias reactivas a partir de los yoduros de alquilo adecuados. En las transformaciones estudiadas, la formación de los radicales es a través de la escisión reductora del enlace carbono-yodo del precursor de yoduro de alquilo mediante mecanismos de transferencia de un solo electrón (SET). Inicialmente, he desarrollado un nuevo enfoque para la perfluoroalquilación fotoquímica directa de fenoles sustituidos. El uso de luz visible simple, sin necesidad de ningún fotocatalizador o iniciador de radicales, puede promover la perfluoroalquilación o trifluorometilación aromática de fenoles a temperatura ambiente. En un segundo proyecto, he desarrollado una nueva metodología para la metilación o bencilación en α de aldehídos mediante fotoorganocatálisis. En este caso, la reacción se produce en ausencia de catalizadores fotoredox externos, y los compuestos deseados se obtienen con buenos rendimientos aislados y elevada enantioselectividad.
The chemistry developed during my doctoral thesis was driven by the ability of electron rich intermediates (phenolate anions and chiral enamines), transiently generated from photochemically inactive precursors (phenols and aldehydes), to directly reach an electronically excited state upon light absorption and subsequently promoting the formation of reactive radical species from suitable alkyl iodides. In the studied transformations, the radicals are formed through the reductive cleavage of the carbon-iodine bond within the alkyl iodide precursor via single-electron transfer (SET) mechanisms. Initially, I developed a new approach for the photochemical direct perfluoroalkylation of substituted phenols. The use of simple visible light, without the need of any photocatalyst or radical initiator, can promote an aromatic perfluoroalkylation or trifluoromethylation of phenols at ambient temperature. In a second project, I developed a new methodology for the enantioselective formal α-methylation and α-benzylation of aldehydes by means of photo-organocatalysis. The reaction occurs in the absence of external photoredox catalysts, and the desired compounds were obtained in good isolated yields with high enantioselectivity.
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Shrestha, Sweta. "Application of Transition Metal Coordination for Energy Efficient Processes: Catalysis and Separation." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1502975499629018.

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Zeng, Tao. "Three-Dimensional Model Analysis of Tropospheric Photochemical Processes in the Arctic and Northern Mid_Latitudes." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7648.

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Halogen-driven ozone and nonmethane hydrocarbon losses in springtime Arctic boundary layer are investigated using a regional chemical transport model (CTM). Surface observation of O3 at Alert and Barrow and aircraft observations of O3 and hydrocarbons during the TOPSE experiment from February to May in 2000 are analyzed. We prescribe halogen radical distributions based on GOME BrO observations and calculated or observed other halogen radical to BrO ratios. GOME BrO shows an apparent anti-correlation with surface temperature over high BrO regions. At its peak, area of simulated near-surface O3 depletions (O3 LT 20ppbv) covers GT 50% of the north high latitudes. Model simulated O3 losses are in agreement with surface and aircraft O3 observations. Simulation of halogen distributions are constrained using aircraft hydrocarbon measurements. We find the currently chemical mechanism overestimate the Cl/BrO ratios. The model can reproduce the observed halogen loss of NMHCs using the empirical Cl/BrO ratios. We find that the hydrocarbon loss is not as sensitive to the prescribed boundary layer height of halogen as that of O3, therefore producing a more robust measure for evaluating satellite column measurement. Tropospheric tracer transport and chemical oxidation processes are examined on the basis of the observations at northern mid-high latitudes and over the tropical Pacific and the corresponding global 3D CTM (GEOS-CHEM) simulations. The correlation between propane and ethane/propane ratio is employed using a finite mixing model to examine the mixing in addition to the OH oxidations. At northern mid-high latitudes the model agrees with the observations before March. The model appears to overestimate the transport from lower to middle latitudes and the horizontal transport and mixing at high latitudes in May. Over the tropical Pacific the model reproduces the observed two-branch slope values reflecting an underestimate of continental convective transport at northern mid-latitudes and an overestimate of latitudinal transport into the tropics. Inverse modeling using the subsets of observed and simulated data is more reliable by reducing (systematic) biases introduced by systematic model transport model transport errors. On the basis of this subset we find the model underestimates the emissions of ethane and propane by 14 5%.
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Malpass, Simon. "Oxidant, particle and photochemical processes in the atmosphere above a Southeast Asian rain forest." Thesis, University of York, 2011. http://etheses.whiterose.ac.uk/2366/.

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A major source of radical species in the atmosphere is through the oxidation reactions of biogenic volatile organic compounds that are emitted from vegetation. Tropical rainforests are responsible for over half of such biogenic species that are emitted into the atmosphere and the local, regional and global impacts of their subsequent oxidation mechanisms are currently not well understood. Further, with tropical forests being removed to make way for new land uses (such as oil palm plantations), the subsequent change in the quantity and type of biogenic emissions into the atmosphere could have far-reaching impacts. The Oxidant, Particle and Photochemical Processes (OP3) field campaign conducted at Bukit Atur in Malaysian Borneo in 2008, aimed to address some of the uncertainties that currently exist surrounding the impact of forested regions on atmospheric chemistry. In particular, this project aims to predict the concentrations of OH, HO2 and RO2 radicals at Bukit Atur in Borneo during April and July of 2008, using a near-explicit photochemical box model with 15,000 reactions and 7,200 species. The model is constrained using observations made during the two experimental campaigns, and used to compare with radical measurements. In agreement with previous studies involving tropical forests, it was found that the standard model based on the Master Chemical Mechanism (MCM v3.1) underestimates the observed concentrations of OH by a factor of 0.5 on average and overestimates HO2 concentrations by a factor of 2. The results for RO2 were mixed with some days over-predicted and some under-predicted. The implementation of some new theoretically derived reaction pathways without the isoprene degradation scheme improved the predicted OH concentration (modelled:measured ratio improved to 0.3), but did not improve the HO2 estimation (modelled: measured ratio changed to 2.5). It was found that the modelled: measured discrepancy was better on days when the VOC:NOX ratio was lower, suggesting that even with the updated isoprene scheme, days with high biogenic concentrations are not well represented in the model. A rate of production analysis also confirmed that days where modelled OH agreed best with measurements were dominated more by NOX reactions, and less by for instance, Criegee biradical reactions, the latter an indication of biogenic influence. It seems likely from the results from this study (and others) that the suggested alterations to the isoprene chemistry scheme are incomplete, as they do not completely remove the model discrepancy in the predicted OH and HO2 concentrations. This work provides a useful contribution to the understanding of radical species production in tropical forests and provides more data in this area of research. However, this project also identifies that more research is required, particularly in the elucidation of isoprene degradation in the atmosphere, but also with issues such as the dry deposition rates of key intermediates in the model mechanism.
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Yamazaki, Shohei. "A method for locating conical intersection in solvated molecules and application to photochemical processes." 京都大学 (Kyoto University), 2007. http://hdl.handle.net/2433/136734.

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Books on the topic "Photochemical processes"

1

Ramamurthy, V. Supramolecular photochemistry: Controlling photochemical processes. Hoboken, NJ: Wiley, 2011.

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Supramolecular photochemistry: Controlling photochemical processes. Hoboken, NJ: Wiley, 2011.

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Gardner, Edward P. The primary photochemical processes of acrolein. Research Triangle Park, NC: U.S. Environmental Protection Agency, Atmospheric Sciences Research Laboratory, 1986.

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Hess, Peter. Photoacoustic, Photothermal and Photochemical Processes in Gases. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989.

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Hess, Peter, ed. Photoacoustic, Photothermal and Photochemical Processes in Gases. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-83851-4.

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Joint Workshop COST 611/Working Party 2 and EUROTRAC (1990 Madrid, Spain). Joint Workshop COST 611/Working Party 2 and EUROTRAC: Atmospheric oxidation processes, September 25-27, 1990, Madrid/Spain. Brussel: E. Guyot, 1991.

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Hess, Peter. Photoacoustic, Photothermal and Photochemical Processes at Surfaces and in Thin Films. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989.

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Hess, Peter, ed. Photoacoustic, Photothermal and Photochemical Processes at Surfaces and in Thin Films. Berlin, Heidelberg: Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/978-3-642-83945-0.

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P, Hess, Boccara A. C, and Physikzentrum (Bad Honnef Germany), eds. Photoacoustic, photothermal, and photochemical processes at surfaces and in thin films. Berlin: Springer-Verlag, 1989.

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Mechanisms of photophysical processes and photochemical reactions in polymers: Theory and applications. Chichester [West Sussex]: Wiley, 1987.

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Book chapters on the topic "Photochemical processes"

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Rodgers, M. A. J. "Primary Photochemical Processes." In Photosensitisation, 11–18. Berlin, Heidelberg: Springer Berlin Heidelberg, 1988. http://dx.doi.org/10.1007/978-3-642-73151-8_2.

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Moortgat, Geert K. "PhotoChemical Processes in the Atmosphere." In Global Atmospheric Change and its Impact on Regional Air Quality, 115–20. Dordrecht: Springer Netherlands, 2002. http://dx.doi.org/10.1007/978-94-010-0082-6_18.

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Bäuerle, Dieter. "Thermal, Photophysical, and Photochemical Processes." In Laser Processing and Chemistry, 13–38. Berlin, Heidelberg: Springer Berlin Heidelberg, 2011. http://dx.doi.org/10.1007/978-3-642-17613-5_2.

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Majer, J. R., and J. P. Simons. "Photochemical Processes in Halogenated Compounds." In Advances in Photochemistry, 137–81. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470133323.ch4.

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Santarelli, Francesco. "Radiative Transfer in Photochemical Processes." In Photoelectrochemistry, Photocatalysis and Photoreactors, 549–59. Dordrecht: Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-015-7725-0_24.

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Bäuerle, Dieter. "Thermal, Photophysical, and Photochemical Processes." In Advanced Texts in Physics, 13–37. Berlin, Heidelberg: Springer Berlin Heidelberg, 2000. http://dx.doi.org/10.1007/978-3-662-04074-4_2.

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Bäuerle, Dieter. "Thermal, Photophysical, and Photochemical Processes." In Laser Processing and Chemistry, 13–38. Berlin, Heidelberg: Springer Berlin Heidelberg, 1996. http://dx.doi.org/10.1007/978-3-662-03253-4_2.

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Vione, Davide. "Photochemical Transformation Processes of Environmental Significance." In Tomorrow's Chemistry Today, 395–419. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2010. http://dx.doi.org/10.1002/9783527628902.ch17.

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Richard, Claire, and Norbert Hoffmann. "Chapter 4. Direct Photolysis Processes." In Comprehensive Series in Photochemical & Photobiological Sciences, 61–75. Cambridge: Royal Society of Chemistry, 2015. http://dx.doi.org/10.1039/9781782622154-00061.

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Wang, Ying. "Photophysical and Photochemical Processes of Semiconductor Nanoclusters." In Advances in Photochemistry, 179–234. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470133507.ch3.

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Conference papers on the topic "Photochemical processes"

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Jaber, Jad, James Hamzik, Nicholas Filipancic, Justin Brewster, and Annie Xia. "Addressing metallic contaminants in the photochemical supply chain." In Advances in Patterning Materials and Processes XXXVII, edited by Roel Gronheid and Daniel P. Sanders. SPIE, 2020. http://dx.doi.org/10.1117/12.2551646.

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Grishina, Antonina D., Anatoly V. Vannikov, Galina O. Khazova, Marine G. Tedoradze, and Yurij I. Koltsov. "Photochemical processes in photoresists containing electron donor molecules." In Optical Information Science and Technology, edited by Andrei L. Mikaelian. SPIE, 1998. http://dx.doi.org/10.1117/12.301424.

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Akselrod, L., H. J. Byrne, C. Thomsen, and S. Roth. "A spectroscopic analysis of photochemical processes in fullerenes." In International Conference on Science and Technology of Synthetic Metals. IEEE, 1994. http://dx.doi.org/10.1109/stsm.1994.834646.

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Maharjan, Kusum, Iou-Sheng Ke, Sabrina Wong, Aiwen Wu, Ying Qi, James Hamzik, and Lawrence Chen. "Removing metallic contaminants from photochemical solvents using advanced purification technologies." In Advances in Patterning Materials and Processes XXXIX, edited by Douglas Guerrero and Daniel P. Sanders. SPIE, 2022. http://dx.doi.org/10.1117/12.2614308.

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Ogura, T., Y. Yamakage, T. Inoue, and M. Hirose. "Surface Processes in Fluorine-Based Photochemical Etching of Silicon." In 1986 International Conference on Solid State Devices and Materials. The Japan Society of Applied Physics, 1986. http://dx.doi.org/10.7567/ssdm.1986.a-4-3.

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Luey, Kenneth T., and Dianne J. Coleman. "Photochemical processes in a two-component molecular contaminant film." In Optical Engineering + Applications, edited by Sharon A. Straka. SPIE, 2008. http://dx.doi.org/10.1117/12.793502.

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Melzer, Madeline E., Priscilla Lopez, Gary Noojin, Amanda Tijerina, Harvey Hodnett, Matthew A. Macasadia, and Michael L. Denton. "Distinguishing photothermal from photochemical damage processes at 447 nm." In Optical Interactions with Tissue and Cells XXXIII and Advanced Photonics in Urology, edited by Hyun Wook Kang, Ronald Sroka, Bennett L. Ibey, and Norbert Linz. SPIE, 2022. http://dx.doi.org/10.1117/12.2609049.

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Danilova, E. D., L. V. Коlomeichuk, and M. V. Efimova. "Influence of chloride salinity on primary photosynthetic processes in potato leaves." In 2nd International Scientific Conference "Plants and Microbes: the Future of Biotechnology". PLAMIC2020 Organizing committee, 2020. http://dx.doi.org/10.28983/plamic2020.056.

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Raddi, S. "Remote Sensing Of Photosynthetic Processes By Photochemical Reflectance Index (PRI)." In EARTH OBSERVATION FOR VEGETATION MONITORING AND WATER MANAGEMENT. AIP, 2006. http://dx.doi.org/10.1063/1.2349348.

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Sekiguchi, Atsushi, Mikio Kadoi, Yasuhiro Miyake, Toshiharu Matsuzawa, and Chris A. Mack. "Development of analysis system for F 2 -excimer laser photochemical processes." In Microlithography 2000, edited by Francis M. Houlihan. SPIE, 2000. http://dx.doi.org/10.1117/12.388324.

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Reports on the topic "Photochemical processes"

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Walker, David, Craig Baker-Austin, Andy Smith, Karen Thorpe, Adil Bakir, Tamara Galloway, Sharron Ganther, et al. A critical review of microbiological colonisation of nano- and microplastics (NMP) and their significance to the food chain. Food Standards Agency, April 2022. http://dx.doi.org/10.46756/sci.fsa.xdx112.

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Microplastics are extremely small mixed shaped plastic debris in the environment. These plastics are manufactured (primary microplastics) or formed from the breakdown of larger plastics once they enter the terrestrial, freshwater and marine environments (secondary microplastics). Over time, a combination of physical, photochemical and biological processes can reduce the structural integrity of plastic debris to produce microplastics and even further to produce nanoplastics. NMPs have been detected in both the aquatic and terrestrial environments and can be easily spread by water, soil and air and can be ingested by a wide range of organisms. For example, NMPs have been found in the guts of fish and bivalve shellfish. Microplastics have also been detected in food and in human faeces. Therefore, NMPs are not only found in the environment, but they may contaminate the food supply chain and be ingested by consumers. There is evidence suggesting that microorganisms are able to colonise the surfaces of microplastics and aggregates of nanoplastics. However, the risk to consumers posed by NMPs colonised with microorganisms (including those that are AMR) which enter the food supply chain is currently unknown.
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Wurl, Oliver. Biofilm-like habitat at the sea-surface: A mesocosm study, Cruise No. POS537, 14.09.2019 – 04.10.2019, Malaga (Spain) – Cartagena (Spain) - BIOFILM. University of Oldenburg, November 2020. http://dx.doi.org/10.3289/cr_pos537.

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OceanRep OceanRep Startseite Kontakt Schnellsuche Einfache Suche Erweiterte Suche Blättern Autor Forschungsbereich Publikationsart Jahr Studiengang Neuzugänge Artikel – begutachtet Alle Über uns GEOMAR Bibliothek Open Access Policies Grundsätze Hilfe FAQs Statistik Impressum Biofilm-like habitat at the sea-surface: A mesocosm study, Cruise No. POS537, 14.09.2019 – 04.10.2019, Malaga (Spain) – Cartagena (Spain) - BIOFILM . Logged in as Heidi Düpow Einträge verwaltenManage recordsManage shelvesProfilGespeicherte SuchenBegutachtungAdminLogout - Tools Wurl, Oliver, Mustaffa, Nur Ili Hamizah, Robinson, Tiera-Brandy, Hoppe, Jennifer, Jaeger, Leonie, Striebel, Maren, Heinrichs, Anna-Lena, Hennings, Laura Margarethe, Goncalves, Rodrigo, Ruiz Gazulla, Carlota und Ferrera, Isabel (2020) Biofilm-like habitat at the sea-surface: A mesocosm study, Cruise No. POS537, 14.09.2019 – 04.10.2019, Malaga (Spain) – Cartagena (Spain) - BIOFILM . Open Access . POSEIDON Berichte . University of Oldenburg, Oldenburg, 35 pp. [img] Text Cruise_Reports_POS537_final.pdf - publizierte Version Available under License Creative Commons: Attribution 4.0. Download (2417Kb) | Vorschau Abstract Biofilm-like properties can form on sea surfaces, but an understanding of the underlying processes leading to the development of these biofilms is not available. We used approaches to study the development of biofilm-like properties at the sea surface, i.e. the number, abundance and diversity of bacterial communities and phytoplankton, the accumulation of gel-like particles and dissolved tracers. During the expedition POS537 we used newly developed and free drifting mesocosms and performed incubation experiments. With these approaches we aim to investigate the role of light and UV radiation as well as the microbes themselves, which lead to the formation of biofilms. With unique microbial interactions and photochemical reactions, sea surface biofilms could be biochemical reactors with significant implications for ocean and climate research, e.g. with respect to the marine carbon cycle, diversity of organisms and oceanatmosphere interactions.
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LONG, KRISTY M., GORDON D. JARVINEN, and DORIS K. FORD. PHOTOCHEMICAL OXIDATION OF OXALATE, UREA, AND HYDROXYLAMMONIUM IN PU-238 PROCESS STREAMS. Office of Scientific and Technical Information (OSTI), August 2006. http://dx.doi.org/10.2172/1087619.

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Nelson, Nathan, and Charles F. Yocum. Structure, Function and Utilization of Plant Photosynthetic Reaction Centers. United States Department of Agriculture, September 2012. http://dx.doi.org/10.32747/2012.7699846.bard.

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Light capturing and energy conversion by PSI is one of the most fundamental processes in nature. In the heart of these adaptations stand PSI, PSII and their light harvesting antenna complexes. The main goal of this grant proposal was to obtain by X-ray crystallography information on the structure of plant photosystem I (PSI) and photosystem II (PSII) supercomplexes. We achieved several milestones along this line but as yet, like several strong laboratories around the world, we have no crystal structure of plant PSII. We have redesigned the purification and crystallization procedures and recently solved the crystal structure of the PSI supercomplex at 3.3 Å resolution. Even though this advance in resolution appears to be relatively small, we obtained a significantly improved model of the supercomplex. The work was published in J. Biol. Chem. (Amunts et al., 2010). The improved electron density map yielded identification and tracing of the PsaK subunit. The location of an additional 10 ß-carotenes, as well as 5 chlorophylls and several loop regions that were previously uninterruptable have been modeled. This represents the most complete plant PSI structure obtained thus far, revealing the locations of and interactions among 17 protein subunits and 193 non-covalently bound photochemical cofactors. We have continued extensive experimental efforts to improve the structure of plant PSI and to obtain PSII preparation amenable to crystallization. Most of our efforts were devoted to obtain well-defined subcomplexes of plant PSII preparations that are amenable to crystallization. We studied the apparent paradox of the high sensitivity of oxygen evolution of isolated thylakoids while BBY particles exhibit remarkable resilience to the same treatment. The integrity of the photosystem II (PSII) extrinsic protein complement as well as calcium effects arise from the Ca2+ atom associated with the site of photosynthetic water oxidation were investigated. This work provides deeper insights into the interaction of PsbO with PSII. Sight-directed mutagenesis indicated the location of critical sites involved in the stability of the water oxidation reaction. When combined with previous results, the data lead to a more detailed model for PsbO binding in eukaryotic PSII.
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Ohad, Itzhak, and Himadri Pakrasi. Role of Cytochrome B559 in Photoinhibition. United States Department of Agriculture, December 1995. http://dx.doi.org/10.32747/1995.7613031.bard.

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The aim of this research project was to obtain information on the role of the cytochrome b559 in the function of Photosystem-II (PSII) with special emphasis on the light induced photo inactivation of PSII and turnover of the photochemical reaction center II protein subunit RCII-D1. The major goals of this project were: 1) Isolation and sequencing of the Chlamydomonas chloroplast psbE and psbF genes encoding the cytochrome b559 a and b subunits respectively; 2) Generation of site directed mutants and testing the effect of such mutation on the function of PSII under various light conditions; 3) To obtain further information on the mechanism of the light induced degradation and replacement of the PSII core proteins. This information shall serve as a basis for the understanding of the role of the cytochrome b559 in the process of photoinhibition and recovery of photosynthetic activity as well as during low light induced turnover of the D1 protein. Unlike in other organisms in which the psbE and psbF genes encoding the a and b subunits of cytochrome b559, are part of an operon which also includes the psbL and psbJ genes, in Chlamydomonas these genes are transcribed from different regions of the chloroplast chromosome. The charge distribution of the derived amino-acid sequences of psbE and psbF gene products differs from that of the corresponding genes in other organisms as far as the rule of "positive charge in" is concerned relative to the process of the polypeptide insertion in the thylakoid membrane. However, the sum of the charges of both subunits corresponds to the above rule possibly indicating co-insertion of both subunits in the process of cytochrome b559 assembly. A plasmid designed for the introduction of site-specific mutations into the psbF gene of C. reinhardtii. was constructed. The vector consists of a DNA fragment from the chromosome of C. reinhardtii which spans the region of the psbF gene, upstream of which the spectinomycin-resistance-conferring aadA cassette was inserted. This vector was successfully used to transform wild type C. reinhardtii cells. The spectinomycin resistant strain thus obtained can grow autotrophically and does not show significant changes as compared to the wild-type strain in PSII activity. The following mutations have been introduced in the psbF gene: H23M; H23Y; W19L and W19. The replacement of H23 involved in the heme binding to M and Y was meant to permit heme binding but eventually alter some or all of the electron transport properties of the mutated cytochrome. Tryptophane W19, a strictly conserved residue, is proximal to the heme and may interact with the tetrapyrole ring. Therefore its replacement may effect the heme properties. A change to tyrosine may have a lesser affect on the potential or electron transfer rate while a replacement of W19 by leucine is meant to introduce a more prominent disturbance in these parameters. Two of the mutants, FW19L and FH23M have segregated already and are homoplasmic. The rest are still grown under selection conditions until complete segregation will be obtained. All mutants contain assembled and functional PSII exhibiting an increased sensitivity of PSII to the light. Work is still in progress for the detailed characterization of the mutants PSII properties. A tobacco mutant, S6, obtained by Maliga and coworkers harboring the F26S mutation in the b subunit was made available to us and was characterized. Measurements of PSII charge separation and recombination, polypeptide content and electron flow indicates that this mutation indeed results in light sensitivity. Presently further work is in progress in the detailed characterization of the properties of all the above mutants. Information was obtained demonstrating that photoinactivation of PSII in vivo initiates a series of progressive changes in the properties of RCII which result in an irreversible modification of the RCII-D1 protein leading to its degradation and replacement. The cleavage process of the modified RCII-D1 protein is regulated by the occupancy of the QB site of RCII by plastoquinone. Newly synthesized D1 protein is not accumulated in a stable form unless integrated in reassembled RCII. Thus the degradation of the irreversibly modified RCII-D1 protein is essential for the recovery process. The light induced degradation of the RCII-D1 protein is rapid in mutants lacking the pD1 processing protease such as in the LF-1 mutant of the unicellular alga Scenedesmus obliquus. In this case the Mn binding site of PSII is abolished, the water oxidation process is inhibited and harmful cation radicals are formed following light induced electron flow in PSII. In such mutants photo-inactivation of PSII is rapid, it is not protected by ligands binding at the QB site and the degradation of the inactivated RCII-D1 occurs rapidly also in the dark. Furthermore the degraded D1 protein can be replaced in the dark in absence of light driven redox controlled reactions. The replacement of the RCII-D1 protein involves the de novo synthesis of the precursor protein, pD1, and its processing at the C-terminus end by an unknown processing protease. In the frame of this work, a gene previously isolated and sequenced by Dr. Pakrasi's group has been identified as encoding the RCII-pD1 C-terminus processing protease in the cyanobacterium Synechocystis sp. PCC 6803. The deduced sequence of the ctpA protein shows significant similarity to the bovine, human and insect interphotoreceptor retinoid-binding proteins. Results obtained using C. reinhardtii cells exposes to low light or series of single turnover light flashes have been also obtained indicating that the process of RCII-D1 protein turnover under non-photoinactivating conditions (low light) may be related to charge recombination in RCII due to back electron flow from the semiquinone QB- to the oxidised S2,3 states of the Mn cluster involved in the water oxidation process.
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