Relevant bibliographies by topics / Photochemical Properties - Organic Moleculecules

Contents

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

Academic literature on the topic 'Photochemical Properties - Organic Moleculecules'

Author: Grafiati
Published: 7 September 2023

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Photochemical Properties - Organic Moleculecules.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Photochemical Properties - Organic Moleculecules"

1

Leyva, Elisa, Denisse de Loera, Claudia G. Espinosa-González, and Saúl Noriega. "Physicochemical Properties and Photochemical Reactions in Organic Crystals." Current Organic Chemistry 23, no. 3 (May 9, 2019): 215–55. http://dx.doi.org/10.2174/1385272822666190313152105.

Full text
Abstract:
Background: Molecular organic photochemistry is concerned with the description of physical and chemical processes generated upon the absorption of photons by organic molecules. Recently, it has become an important part of many areas of science: chemistry, biology, biochemistry, medicine, biophysics, material science, analytical chemistry, among others. Many synthetic chemists are using photochemical reactions in crystals to generate different types of organic compounds since this methodology represents a green chemistry approach. Objective & Method: Chemical reactions in crystals are quite different from reactions in solution. The range of organic solid state reactions and the degree of control which could be achieved under these conditions are quite wider and subtle. Therefore, for a large number of molecular crystals, the photochemical outcome is not the expected product based on topochemical principles. To explain these experimental results, several physicochemical factors in crystal structure have been proposed such as defects, reaction cavity, dynamic preformation or photoinduced lattice instability and steric compression control. In addition, several crystal engineering strategies have been developed to bring molecules into adequate orientations with reactive groups in good proximity to synthesize complex molecules that in many cases are not available by conventional methods. Some strategies involve structural modifications like intramolecular substitution with different functional groups to modify intermolecular interactions. Other strategies involve chemical techniques such as mixed crystal formation, charge transfer complexes, ionic and organometallic interactions. Furthermore, some examples of the single crystal to single crystal transformations have also been developed showing an elegant method to achieve regio and stereoselectivity in a photochemical reaction. Conclusion: The several examples given in this review paper have shown the wide scope of photochemical reactions in organic molecular crystals. There are several advantages of carrying photochemical reaction in the solid state. Production of materials unobtainable by the traditional solution phase reactions, improved specificity, reduction of impurities, and enhancement in the yields by the reduction of side reactions. These advantages and the multidisciplinary nature of solid-state photochemistry make this discipline quite likely to develop a lot in the future.
APA, Harvard, Vancouver, ISO, and other styles
2

Porcal, P., P. J. Dillon, and L. A. Molot. "Seasonal changes in photochemical properties of dissolved organic matter." Biogeosciences Discussions 10, no. 3 (March 27, 2013): 5977–6006. http://dx.doi.org/10.5194/bgd-10-5977-2013.

Full text
Abstract:
Abstract. The fate of dissolved organic matter (DOM) in lakes and streams is significantly affected by photochemical transformation of DOM. A series of laboratory photochemical experiments was conducted to describe long-term changes in photochemical properties of DOM. The stream samples used in this study originated from three different catchments on the southern-most part of the Boreal ecozone near Dorset, Ontario, Canada. A first-order kinetics equation was used to model photochemical degradation of DOM and the kinetic rate constant, K, was used as an indicator of photochemical properties of DOM. Highest Kwas observed in samples from the catchment dominated by coniferous forest while the lowest K was measured in the deciduous catchment. Kinetic rate constants from all three catchments showed a sinusoidal pattern during the hydrological year. K increased steadily during autumn and winter and decreased during spring and summer. The highest values were observed during spring melt events when DOM was flushed from terrestrial sources by high flows. The minimum rate constants were found in summer when discharge was lowest. DOM molecular weight and specific absorbance at 254 nm also exhibited annual cycles corresponding to the seasonal cycles of terrestrial organic matter but the relationships between these properties and K was probably affected by previous exposure to solar radiation during transit from the catchment as well as pH and iron.
APA, Harvard, Vancouver, ISO, and other styles
3

Budyka, M. F., M. M. Kantor, and R. M. Fatkulbayanov. "Photochemical properties of 9-(4-azidophenyl)acridine." Chemistry of Heterocyclic Compounds 33, no. 11 (November 1997): 1301–5. http://dx.doi.org/10.1007/bf02320332.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Zakharova, Natalia, Olga Savinova, and Akmaral Utelbayeva. "Photochemical Properties of Propargylamine-based Polymers." Materiale Plastice 58, no. 3 (October 5, 2021): 32–40. http://dx.doi.org/10.37358/mp.21.3.5501.

Full text
Abstract:
Propargylamines are a promising but quite poorly studied category of organic compounds. This work aimed to study the photochemical properties of propargylamines polymers containing porphyrin fragments with electron transfer reactions. The study was carried out in 2019 at the Institute of Organic Chemistry (RAS, Moscow, Russia). The obtained polymer was irradiated with a luminous source. The absorption spectra were studied by electron paramagnetic resonance using a radio spectrometer. The presence of porphyrin and propargylamine in the polymer solution has been established to promote the reaction of complexation. This is due to the presence of double bonds in the amino groups, whereas also porphyrin and bromanil, which is an electron acceptor. The resulting data allow explaining the processes involved in photochemical reactions during the irradiation of the porphyrin complex in the presence of bromanil. In the long-wavelength part of the spectrum (above 540 nm), electron phototransfer inside the polymer molecule to the porphyrin side and between molecules from the porphyrin anion radical to the neutral polymer molecule take place.
APA, Harvard, Vancouver, ISO, and other styles
5

Zakharova, Natalia, Olga Savinova, and Akmaral Utelbayeva. "Photochemical Properties of Propargylamine-based Polymers." Materiale Plastice 58, no. 3 (October 5, 2021): 32–40. http://dx.doi.org/10.37358/mp.21.3.5501.

Full text
Abstract:
Propargylamines are a promising but quite poorly studied category of organic compounds. This work aimed to study the photochemical properties of propargylamines polymers containing porphyrin fragments with electron transfer reactions. The study was carried out in 2019 at the Institute of Organic Chemistry (RAS, Moscow, Russia). The obtained polymer was irradiated with a luminous source. The absorption spectra were studied by electron paramagnetic resonance using a radio spectrometer. The presence of porphyrin and propargylamine in the polymer solution has been established to promote the reaction of complexation. This is due to the presence of double bonds in the amino groups, whereas also porphyrin and bromanil, which is an electron acceptor. The resulting data allow explaining the processes involved in photochemical reactions during the irradiation of the porphyrin complex in the presence of bromanil. In the long-wavelength part of the spectrum (above 540 nm), electron phototransfer inside the polymer molecule to the porphyrin side and between molecules from the porphyrin anion radical to the neutral polymer molecule take place.
APA, Harvard, Vancouver, ISO, and other styles
6

Lastovoy, Anton P., Nina A. Kuznetsova, Ludmila K. Slivka, and Elena A. Makarova. "Photochemical properties of substituted tetraazachlorins." Journal of Porphyrins and Phthalocyanines 18, no. 06 (June 2014): 457–64. http://dx.doi.org/10.1142/s1088424614500187.

Full text
Abstract:
The photochemical properties of water-insoluble metal-free tetraazachlorin derivatives in organic solvents and aqueous micellar solutions of nonionic surfactants were investigated. The quantum yields of fluorescence, singlet oxygen generation and photodegradation were evaluated in benzene. The highest photostability and singlet oxygen quantum yield (ΦΔ = 0.7) was found for 2,2,3,3-tetramethyl-7,8,12,13,17,18-hexaphenyltetraazachlorin. The moderate ΦΔ values (0.21–0.35) of triarenotetraazachlorins in benzene were established. Expansion of tetraazachlorin π-system by fusion of three aromatic rings leads to reduction of efficiency of singlet oxygen generation. The study of photodegradation mechanism shows that radical photooxidation apparently is most plausible, though 1 O 2 may partly contribute to photodestruction of some tetraazachlorins. In aqueous colloidal solution of nonionic surfactant (Cremophor EL) the same, as in benzene, effect of sensitizer structure upon efficacy of singlet oxygen production was observed. It was shown that 1 O 2 diffusion from micelle core into solution and then to target slows its oxidation rate substantially in comparison to the case where sensitizer and target are localized in the same micelle.
APA, Harvard, Vancouver, ISO, and other styles
7

Rybkin, Alexander Yu, Alexandra Yu Belik, Pavel A. Tarakanov, Kamil R. Taziev, Alexei V. Kozlov, Nikolay S. Goryachev, Ilya V. Sulimenkov, et al. "Pyropheophorbide-Fullerene Dyad: Synthesis and Photochemical Properties." Macroheterocycles 12, no. 2 (2019): 181–86. http://dx.doi.org/10.6060/mhc190446r.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Porcal, P., P. J. Dillon, and L. A. Molot. "Seasonal changes in photochemical properties of dissolved organic matter in small boreal streams." Biogeosciences 10, no. 8 (August 16, 2013): 5533–43. http://dx.doi.org/10.5194/bg-10-5533-2013.

Full text
Abstract:
Abstract. The fate of dissolved organic matter (DOM) in lakes and streams is significantly affected by photochemical transformation of DOM. A series of laboratory photochemical experiments was conducted to describe seasonal changes in photochemical properties of DOM. The stream samples used in this study originated from three different catchments in the southernmost part of the Boreal ecozone near Dorset, Ontario, Canada. A first-order kinetics equation was used to model photochemical degradation of DOM and the kinetic rate constant, K, was used as an indicator of photochemical properties of DOM. Kinetic rate constants from all three catchments showed a sinusoidal pattern during the hydrological year. K increased steadily during autumn and winter and decreased during spring and summer with a more than 3-fold range in each stream. The highest values were observed during spring melt events when DOM was flushed from terrestrial sources by high flows. The minimum rate constants were found in summer when discharge was lowest. K was strongly correlated with pH and iron. DOM molecular weight and specific absorbance at 254 nm also exhibited annual cycles corresponding to the seasonal cycles of terrestrial organic matter, but the relationships between these properties and K differed between seasons and may have been affected by previous exposure to solar radiation during transit from the catchment.
APA, Harvard, Vancouver, ISO, and other styles
9

Grishin, I. Yu, Yu M. Chunaev, N. M. Przhiylgovskaya, I. I. Levina, and A. V. Metelitsa. "Synthesis and photochemical properties of the indoline series fulgides." Chemistry of Heterocyclic Compounds 28, no. 1 (January 1992): 48–52. http://dx.doi.org/10.1007/bf00529478.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Katakami, Chiaki, Shogo Kamo, Ayame Torii, Nobuyuki Hara, Yoshitane Imai, Tohru Taniguchi, Kenji Monde, et al. "Synthesis and Photochemical Properties of Axially Chiral Bis(dinaphthofuran)." Journal of Organic Chemistry 83, no. 23 (October 30, 2018): 14610–16. http://dx.doi.org/10.1021/acs.joc.8b02424.

Full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Photochemical Properties - Organic Moleculecules"

1

Kelly, Graeme P. "Photochemical and photophysical properties of various triaryl-2-pyrazolines." Thesis, Loughborough University, 1987. https://dspace.lboro.ac.uk/2134/28194.

Full text
Abstract:
The main aim of the research was to obtain a detailed insight into the photochemical and photophysical properties of various triaryl-2- pyrazolines, with a view to understanding better their role in photoconductive materials. The technique of laser flash photolysis, in both transmission and diffuse reflectance mode, was employed to study the compounds as microcrystalline powders, within polymer films, on fabrics and in solution. In those media where the triplet state was not directly observed it was sensitized with a suitable triplet energy donor such as benzophenone.
APA, Harvard, Vancouver, ISO, and other styles
2

Chen, Xing. "Theoretical Studies on Magnetic and Photochemical Properties of Organic Molecules." Doctoral thesis, KTH, Teoretisk kemi och biologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-52818.

Full text
Abstract:
The present thesis is concerned with the theoretical studies on magnetic and photochemical properties of organic molecules. The ab initio and first principles theories were employed to investigate the vibrational effects on the isotropic hyperfine coupling constant (HFCC) known as the critical parameter in electron paramagnetic resonance spectrum, the theoretical simulations of the vibronically resolved molecular spectra, the photo-induced reaction mechanism of α-santonin and the spin-forbidden reaction of triplet-state dioxygen with cofactor-free enzyme. The theoretical predictions shed light on the interpretation of experimental observations, the understanding of reaction mechanism, and importantly the guideline and perspective in respect of the popularized applications. We focused on the vibrational corrections to the isotropic HFCCs of hydrogen and carbon atoms in organic radicals. The calculations indicate that the vibrational contributions induce or enhance the effect of spin polarization. A set of rules were stated to guide experimentalist and theoretician in identification of the contributions from the molecular vibrations to HFCCs. And the coupling of spin density with vibrational modes in the backbone is significant and provides the insight into the spin density transfer mechanism in organic π radicals. The spectral characters of the intermediates in solid-state photoarrangement of α-santonin were investigated in order to well understand the underlying experimental spectra. The molecular spectra simulated with Franck-Condon principle show that the positions of the absorption and emission bands of photosantonic acid well match with the experimental observations and the absorption spectrum has a vibrationally resolved character. α-Santonin is the first found organic molecule that has the photoreaction activities. The photorearrangement mechanism is theoretically predicted that the low-lying excited state 1(nπ*) undergoing an intersystem crossing process decays to 3(ππ*) state in the Franck-Condon region. A pathway which is favored in the solid-state reaction requires less space and dynamic advantage on the excited-state potential energy surface (PES). And the other pathway is predominant in the weak polar solvent due to the thermodynamical and dynamical preferences. Lumisantonin is a critical intermediate derived from α-santonin photoreaction. The 3(ππ*) state plays a key role in lumisantonin photolysis. The photolytic pathway is in advantage of dynamics and thermodynamics on the triplet-state PES. In contrast, the other reaction pathway is facile for pyrolysis ascribed to a stable intermediate formed on the ground-state PES.  The mechanism of the oxidation reaction involving cofactor-free enzyme and triplet-state dioxygen were studied. The theoretical calculations show that the charge-transfer mechanism is not a sole way to make a spin-forbidden oxidation allowed. It is more likely to take place in the reactant consisting of a non-conjugated substrate. The other mechanism involving the surface hopping between the triplet- and singlet-state PESs via a minimum energy crossing point (MECP) without a significant charge migration. The electronic state of MECP exhibits a mixed characteristic of the singlet and triplet states. The enhanced conjugation of the substrate slows down the spin-flip rate, and this step can in fact control the rate of the reaction that a dioxygen attaches to a substrate.
QC 20111220
APA, Harvard, Vancouver, ISO, and other styles
3

Reichwagen, Jens. "Synthesis of acene based organic gelators examination of the spectroscopical, photochemical and rheological properties /." [S.l.] : [s.n.], 2005. http://deposit.ddb.de/cgi-bin/dokserv?idn=974938688.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

El-Bjeirami, Oussama. "Photochemical and Photophysical Properties of Gold(I) Complexes and Phosphorescence Sensitization of Organic Luminophores." Thesis, University of North Texas, 2006. https://digital.library.unt.edu/ark:/67531/metadc5375/.

Full text
Abstract:
Two major topics that involve synthetic strategies to enhance the phosphorescence of organic and inorganic luminophores have been investigated. The first topic involves, the photophysical and photochemical properties of the gold (I) complexes LAuIX (L = CO, RNC where R = alkyl or aryl group; X = halide or pseudohalide), which have been investigated and found to exhibit Au-centered phosphorescence and tunable photochemical reactivity. The investigations have shown a clear relationship between the luminescence energies and association modes. We have also demonstrated for the first time that aurophilic bonding and the ligand p-acceptance can sensitize the photoreactivity of Au(I) complexes. The second topic involves conventional organic fluorophores (arenes), which are made to exhibit room-temperature phosphorescence that originates from spin-orbit coupling owing to either an external or internal heavy atom effect in systematically designed systems that contain d10 metals. Facial complexation of polycyclic arenes to tris[{m-(3,4,5,6-tetrafluorophenylene)}mercury(II)], C18F12Hg3 (1) results in crystalline adducts that exhibit bright RGB (red-green-blue) phosphorescence bands at room temperature. This arene-centered phosphorescence is always accompanied by a reduction of the triplet excited state lifetime due to its sensitization by accelerating the radiative instead of the non-radiative decay. The results of both topics are significant for rational design of efficient metal and arene-centered phosphors for molecular light emitting diodes in addition to the fundamental novelties in inorganic chemistry and molecular spectroscopy.
APA, Harvard, Vancouver, ISO, and other styles
5

Tian, Fang. "Studies of LPCVD and anodised TiO←2 thin films and their photoelectrocatalytic photochemical properties for destruction of organic effluents." Thesis, University of Strathclyde, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366874.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Wex, Brigitte. "Photochemical, Photophysical, and Electronic Properties of Fused Ring Systems with Alternating Benzene and Thiophene Units." Bowling Green State University / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1128617994.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Shamaev, Alexei E. "Synthesis, Photochemical Properties and DNA Binding Studies of DNA Cleaving Agents Based on Chiral Dipyridine Dihydrodioxins Salts." Bowling Green State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1445859853.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Blacker, Andrew John. "Recepteurs cyclointercalants et reactifs de photocoupure d'acides nucleiques." Université Louis Pasteur (Strasbourg) (1971-2008), 1988. http://www.theses.fr/1988STR13119.

Full text
Abstract:
Nous avons etudie: les proprietes d'electrochimie, de photochimie et de complexation d'anions d'une serie de recepteurs bases sur un motif ressemblant au methylviologene, le cation 2,7-diazapyrenium; les syntheses et les proprietes de complexation d'une serie de cyclointercalants, incorporant l'element plan, le naphthalene diimide; les proprietes photophysiques d'un recepteur heteroditopique, contenant un groupement intercalant et un element macrocyclique polyammonium et sa capacite de complexer des nucleotides phosphates dans une orientation preferentielle. La photocoupure des acides nucleiques par des cations diazapyreniums a ete clairement demontree par des methodes biochimiques. Deux reactifs cyclointercalants ayant des sus-unites porphyriniques montrent une photocoupure preferentielle des acides nucleiques simple brin. Ces memes composes sont capables d'inactiver certains virus sans endommager leurs cellules hotes
APA, Harvard, Vancouver, ISO, and other styles
9

Chao, Ting-Han, and 趙庭漢. "Synthesis of Dipolar Organic Molecules and Their Photochemical Properties." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/34359752223302602109.

Full text
Abstract:
碩士
中國文化大學
應用化學研究所
93
We starting from Heptcyclotetradecane , we were able to synthesize donor-bridge-acceptor substituted derivatives by condensation reaction . The components for the condensations were Catechol for the donor part , and Acetophenone , 2,4-Dichloroacetophenone , 2,3,4-Trichloroacetophenone , 2,3,4,5,6-Pentafluoroacetophenone for the acceptor part . We used the Diels-Alder reaction and Aldol condensation . Fluorescence spectra provided evidence for efficient photoinduce electron transfer in the different solvent . And from emission spectra we can see the CT band , who can proved photoinduce electron transfer .
APA, Harvard, Vancouver, ISO, and other styles
10

Reichwagen, Jens [Verfasser]. "Synthesis of acene based organic gelators : examination of the spectroscopical, photochemical and rheological properties / von Jens Reichwagen." 2005. http://d-nb.info/974938688/34.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Photochemical Properties - Organic Moleculecules"

1

Nicholls, Colin H., and Peter A. Leermakers. "Photochemical and Spectroscopic Properties of Organic Molecules in Adsorbed or Other Perturbing Polar Environments." In Advances in Photochemistry, 315–36. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470133385.ch7.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Park, Hyeong Ho, Hyung Ho Park, Ho Jung Chang, and Hyeong Tag Jeon. "Study on the Electrical Properties of Direct-Patternable SBT Films Formed by Photochemical Metal-Organic Deposition." In Materials Science Forum, 1061–64. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-431-6.1061.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Das, Suresh, K. George Thomas, and Manapurathu V. George. "Photophysical and Photochemical Properties of Squaraines in Homogeneous and Heterogeneous Media." In Organic Photochemistry, 467–518. CRC Press, 1997. http://dx.doi.org/10.1201/b16837-11.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

S. Patil, Santosh, Lakshmana Reddy Nagappagari, Ganesh Kamble, Diksha E. Shinde, and Kiyoung Lee. "Graphene Related Materials and Composites: Strategies and Their Photocatalytic Applications in Environmental Remediation." In Nanocomposite Materials [Working Title]. IntechOpen, 2022. http://dx.doi.org/10.5772/intechopen.102404.

Full text
Abstract:
Photochemical reactions hold great promise in solving energy and environment related problems and likely contribute towards development of sustainable society. Despite of recent advancements, the inherent catalytic efficiency of conventional photocatalyst has been severely limited by myriad complexity associated with (i) ineffective light absorption in visible region, (ii) unproductive recombination’s of e−/h+ pair in excited state, and (iii) low chemical stability. Contemporary researches on photocatalysts that can be viable for commercial applications has yet to be realized. Graphene has attracted an immense research interests to enhancing the photocatalysts efficiency endowing from their unique optical and electronic properties and salient features such as surface area, mechanical strength and photochemical stability. In this book chapter, we discussed graphene related material (GRMs) to produce hybrid architectures or nanocomposites that can be used as efficient photocatalysts for the degradation of organic pollutants (dyes, pharmaceutical wastes, pesticides etc.) in wastewater. Lastly, we summarize the key insights in photocatalytic electron transfer mechanism, challenges and future perspective which help understand the rationale of GRMs in this field.
APA, Harvard, Vancouver, ISO, and other styles
5

Bernstein, Joel. "Polymorphism and structure–property relations." In Polymorphism in Molecular Crystals, 273–341. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780199655441.003.0006.

Full text
Abstract:
Chapter 6 deals with the connection between the structure and properties of solids as revealed and studied in polymorphic systems. The subject is divided into properties that depend on the one hand on the bulk—that is, the three-dimensional arrangement of the molecules and the interactions among them—and on the other hand the consideration of the crystal as an “oriented gas” serving to act as a matrix for the molecules to permit the study of molecular properties. Among the properties described in the former category are electrical conductivity, organic magnetic materials, photovoltaicity and photoconductivity, second harmonic generation, chromoisomerism, photochromism, thermochromism and mechanochromism, and the mechanosalient effect. The latter category includes a discussion of spectroscopic studies (infrared, Raman, and ultraviolet/visible), excimer phenomena, time-resolved studies of excited states, photochemical reactions and thermal and gas reactions, along with a variety of emission phenomena. The chapter closes with a brief survey of rapidly emerging and developing high pressure studies
APA, Harvard, Vancouver, ISO, and other styles
6

Ramezani, Zahra, Fatemeh Kiani Ghalehsardi, and Siamak Noorizadeh. "Classifications of Quantum Dots and Their Detection Principles in Sensing." In Quantum Dots in Bioanalytical Chemistry and Medicine, 1–36. Royal Society of Chemistry, 2023. http://dx.doi.org/10.1039/9781839169564-00001.

Full text
Abstract:
Quantum dots (QDs) are highly bright fluorescent nanoparticles with high resistance to photobleaching compared to organic fluorophores. They are used extensively as fluorophores in many types of fluorescence sensing; in imaging, phototherapy, and optoelectronic devices; and as catalysts in biochemical and chemical reactions. The use of QDs in the field of sensing is currently a research hotspot, and the synthesis and characterization of newly developed QDs are subjects of active research in many fields. Knowledge of different QDs, their unique properties, and their limitations helps scientists to select appropriate QDs for various applications. This chapter gives a brief history of QD development and discusses its principles and classification. We also provide an overview of development trends that show improvements in QDs’ photochemical and chemical stability as well as reductions in their toxicity. Last but not least, this chapter discusses various sensing mechanisms in QD-based probes in order to provide deep insights into the nature of assembled biosensors and their detection principles in biomedical systems.
APA, Harvard, Vancouver, ISO, and other styles
7

Alexander, Cameron, and Nicole Kirsch. "New methodologies in the preparation of imprinted polymers." In Polymer Chemistry. Oxford University Press, 2004. http://dx.doi.org/10.1093/oso/9780198503095.003.0013.

Full text
Abstract:
Molecular imprinting is a rapidly emerging method for the creation of recognition sites in synthetic polymers, and the resultant materials offer considerable promise as selective adsorbents in a number of applications. The technique exploits the principle of using elements of a target molecule to create its own recognition site. This is achieved by the formation of a highly cross-linked polymeric matrix around a template, which can be the target molecule itself or a close structural analogue. The key to this procedure is to ensure that, during the polymerization, functional groups of the template molecule are fully engaged in interactions with ‘complementary functionality’ of polymer-forming components. These interactions are then ‘locked in’ by the incorporation of the whole assembly into the polymer structure. Subsequent removal of the template reveals the newly created binding sites containing functional groups in the precise stereochemical arrangement to ensure recognition of the target in a highly selective manner (Scheme 1). The first reports of molecular imprinting in organic polymers involved the templating of protected sugars, in the form of esters with a polymerizable boronic acid (however, see Ref. 18 for an earlier example of the imprinting concept) into a cross-linked polymer ‘scaffold’, and variations of the basic technique have now been adopted by many research groups around the world. In general, molecularly imprinted polymers (MIPs) are prepared by thermal or photochemical free-radical routes, employing acrylic or vinylic monomers in a solvent chosen to ensure that the final matrix is microporous. The numbers and types of molecules which have now been imprinted is very large, but a key factor in the preparation of MIP materials with the desired recognition properties is still the chemical nature of the link between the template and the polymer backbone. Consequently, strategies by which the template can be securely fixed in space as the growing matrix forms around it, yet be readily removed to generate the recognition site after polymer synthesis is complete, are of particular interest.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Photochemical Properties - Organic Moleculecules"

1

Karpushenkova, Veronika S., Liliya I. Glinskaya, Yaroslav V. Faletrov, Kseniia N. Bardakova, Yuliya A. Piskun, Sergei V. Kostjuk, and Vladimir M. Shkumatov. "New Photochemical Properties of Azidoaniline and Ciprofloxacin." In International Electronic Conference on Synthetic Organic Chemistry. Basel Switzerland: MDPI, 2022. http://dx.doi.org/10.3390/ecsoc-26-13571.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Katin, Dmitriy, and Sergey Zelentsov. "SYNTHESIS AND PHOTOCHEMICAL PROPERTIES OF POLYOXOMETALATES CONTAINING para – NITROBENZENE PHOSPHOROUS ACID FRAGMENT." In The 14th International Electronic Conference on Synthetic Organic Chemistry. Basel, Switzerland: MDPI, 2010. http://dx.doi.org/10.3390/ecsoc-14-00387.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Morino, S., T. Yamazaki, S. Machida, T. Yamashita, and K. Horie. "Photoinduced Refractive Index Changes in PMMA Films Including a Photochromic Fugide." In Organic Thin Films for Photonic Applications. Washington, D.C.: Optica Publishing Group, 1995. http://dx.doi.org/10.1364/otfa.1995.wtt.5.

Full text
Abstract:
Photochemical reactions such as photochromic reactions, photodegradation and photocrosslinking, change optical properties of the samples during their reactions, and are applicable for optical memories, optical switching devices, and so on[1~3].
APA, Harvard, Vancouver, ISO, and other styles
4

Twieg, R. J., V. Y. Lee, R. D. Miller, C. R. Moylan, W. Volksen, A. Knoesen, R. A. Hill, and D. R. Yankelevich. "Photochemical Stability and Performance of Second Order Nonlinear Optical Chromophores and Polymers." In Organic Thin Films for Photonic Applications. Washington, D.C.: Optica Publishing Group, 1995. http://dx.doi.org/10.1364/otfa.1995.tue.5.

Full text
Abstract:
The performance of χ(2) poled polymer nonlinear optical media is influenced by numerous intrinsic materials properties as well as the specific conditions of subsequent processing and use of the materials. The origins of microscopic optical nonlinearity have now become much better understood and some highly optimized nonlinear optical chromophores have been prepared. The processing to create polar thin polymer films containing these chromophores by application of an electric field is also now much better optimized. Once the polar order is created the influence of temperature (thermal history) on its magnitude has also been studied in great detail and much progress has been made on design of materials with enhanced temporal stability of poled order. In conjunction with this latter effort chromophores with enhanced thermal stability were identified to permit use of high glass transition temperature media.
APA, Harvard, Vancouver, ISO, and other styles
5

Inoue, Hiroyuki, Takashi Iwamoto, Akio Makishima, Makoto Ikemoto, and Kazuyuki Horie. "Preparation and properties of sol-gel thin films with Porphins." In Persistent Spectral Hole Burning: Science and Applications. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/pshb.1991.the7.

Full text
Abstract:
Recently the sol-gel process for preparing amorphous materials has been studied. The low processing temperatures enable us to dope the gel with functional organic molecules. Such molecules have poor thermal stability and cannot be included in traditional oxide glasses. Avnir et al.1,2) have been reported the preparation and optical properties of amorphous silica doped with rhodamine 6G and pyrene. Makishima and Tani3,4) have doped one with 1,4-dihydr-oxy-9,10-anthraquinone (DAQ) and showed photochemical hole burning (PHB) at 4.8 K. They have also demonstrated that other organic molecules can be successfully incorporated into sol-gel matrices. The number of potential applications of such materials is expected to be substantial.
APA, Harvard, Vancouver, ISO, and other styles
6

Rebane, Alexander, Olavi Ollikainen, Heinrich Schwoerer, and Urs P. Wild. "Femtosecond Time-Space Holograms: Diffraction on the Edge of Time." In Spectral Hole-Burning and Related Spectroscopies: Science and Applications. Washington, D.C.: Optica Publishing Group, 1994. http://dx.doi.org/10.1364/shbs.1994.fd3.

Full text
Abstract:
Time- and space domain (TSD) holography [1-3] can be viewed upon as a more general case of conventional holographic process, in which the recording media re members, in addition to the spatial picture, also the spectral intensity of the illuminating light. The resolution of TSD-holograms in time is Fourier-related to the spectral properties of the recording media. The longest time interval that can be recorded is given by the inverse value of the homogeneous width of the zero-phonon line and the shortest time is given by the inverse value of the width of the inhomogeneous distribution in the frequency dimension. By using photochemical spectral hole-burning in organic dye-polymer systems with very broad inhomogeneous bands TSD-holograms of full scenes of ultrafast events with subpicosecond time resolution have been recorded [4, 5].
APA, Harvard, Vancouver, ISO, and other styles
7

Tsuchiya, Jun, Jun-ichi Takahashi, and Hiroshi Tanaka. "Free Volume Model of Thermally Induced Spectral Diffusion." In Persistent Spectral Hole Burning: Science and Applications. Washington, D.C.: Optica Publishing Group, 1991. http://dx.doi.org/10.1364/pshb.1991.the15.

Full text
Abstract:
An organic dye/polymer system, such as free base phthalocyanine (H2Pc) dispersed in polymethylmethacrylate (PMMA), has been interested in as a model material of new mass-storage for photochemical hole burning (PHB)[1]. There are, however, some unsolved problems in applying it to a plactical memory system. That is, the influence of polymers as a matrix over the static and dynamic properties of the system, such as, thermally induced spectral diffussion (TISD), homogeneous and inhomogeneous line width, burning efficiency and so on, has not been solved yet. TISD among them has a strong correlation to micro environment of a polymer dispersing a dye. The disorders in amorphous polymers are seen in wide energy range whose upper limit is determined by the glass transition of polymers. However, the lower limit is still left unknown , although some phenomena are known which are affected by low energy excitation. Recently, hole burning spectroscopy was successfully applied to investigate in the lower energy region [2]. Thermally induced conformation changes of polymers are said to have energy of same size to cause TISD in the lower energy region. Koehler et al. succeeded in explaining the the changes quantitatively from a combination of three independent processes, 1- phonon tunneling process, 2-phonon Raman scattering process and activation process [3]. The material parameters, however, that determine the changes are still unknown. We report TISD results of some dye/polymer systems and correlation between TISD and polymer properties.
APA, Harvard, Vancouver, ISO, and other styles
8

Kulkarni, Sudhir, Kunal Mitra, and Swaminathan Ramesh. "Optical Performance of a Hybrid Nano-Polymer Solar Cell." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-41509.

Full text
Abstract:
Solar energy harvesting is one of the most fundamental solutions to the energy crisis; photovoltaics are the best way to achieve it. Organic based photovoltaics have potential for application as a renewable source of energy. It is cost-effective, light weight, simple and economical to fabricate. Introduction of nanomaterials into polymers is very promising for enhancing photovoltaic conversion efficiency and can potentially improve photochemical and environmental stability. The objective of this paper is to investigate the influence of the nanocomposite film morphology on the optical performance of the hybrid nano-polymer solar cell. The efficiency of such hybrid solar cell depends mainly on the exciton dissociation efficiency and charge mobility. The exciton dissociation efficiency can be improved by increasing the interfacial area between the nanoparticles and polymer. Charge mobility can be improved by proper distribution of nanoparticles in polymer to form better percolation path of each material. Both these parameters are strongly dependant on better distribution of nanoparticles in the polymer. The approach used here is the application of star dispersant, specifically designed for conducting polymers. This dispersant will modify the arms of the conducting polymer to have a high affinity towards nanoparticles and provide better distribution. In this paper the influence on the morphology of the solar cell by the use of star dispersant and corresponding improvement in optical properties and performance is analyzed. Subsequent papers will describe the photovoltaic enhancements of such a solar cell. The solar cell structure chosen here is ITO / PEDOT:PSS / P3HT:TiO2 / Al. A number of specimens are prepared with and without introduction of the star-dispersant. For structural characterization, Scanning Electron Microscopy (SEM) is used. Absorption spectrum analysis and Photoluminescence (PL) analysis are performed to characterize the optical properties of the active layer. Structural characterization revealed that with the application of the dispersant, better mixing of the nanoparticles and the polymer can be achieved. This will in turn increase the interface area and improve exciton dissociation. Better PL quenching is observed in the dispersant modified active layer confirming an improved degree of exciton dissociation.
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Photochemical Properties - Organic Moleculecules"

1

Clark, Catherine D. Photochemical Transformations of the Structural and Optical Properties of Marine Colored Dissolved Organic Material in Coastal Waters. Fort Belvoir, VA: Defense Technical Information Center, August 2001. http://dx.doi.org/10.21236/ada627302.

Full text
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Photochemical Properties - Organic Moleculecules' for particular source types:
Journal articles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography