Search results for "Phosphor"

Electrochemical Oxidative C – C Bond Formation

2021

Oxidative damages in cho-k1 cells treated with beauvericin

2013

Light Regulation of the Thylakoid LHCII Protein Phosphorylation at the Substrate Level

1998

The distribution of light energy between the two photosystems as well as the light-induced turnover of PSII proteins are regulated by the reversible phosphorylation of LHCII and the PSII-core proteins. The thylakoid protein kinase(s) is activated by a signal transduction system involving the interaction of reduced plastoquinone with the quinol oxidation site of the cytochrome bf complex [1]. Phosphorylation of the mobile pool of LHCII induces dissociation of this antenna from PSII and allows its interaction with the PSI in the stroma exposed membranes (state transition)[21. Dephosphorylation of LHCII by a membrane -bound phosphatase appears to be regulated by a cyclophilinlike protein locat…

Contributions to the application of the transferability principle and the multipolar modeling of H atoms: electron-density study of L-histidinium dih…

2006

The electron density of L-histidinium dihydrogen orthophosphate orthophosphoric acid has been determined from X-ray and neutron diffraction data at low temperature (120 K). Topological analysis of the electron density has been used to analyse the effect of the multipolar refinement strategy on the electron-density model in the hydrogen-bonding regions. The electron density at low temperature has also been used to acquire high-quality experimental thermal parameters at room temperature using the transferability principle. Molecular vibrations, TLS and normal mode analysis are discussed and studied at both temperatures.

Correlative Analysis of the Photosynthetic Capacity and Different Components of the Photosynthetic Apparatus

1984

The majority of higher plants is able to adapt to the ecological factor light in a wide range. Depending on the light intensity and the light quality during growth, plant with an equal genotype develop into so-called low light and high light forms. The photosynthetic adaptation to different light conditions involves complex, balanced changes of many leaf features. The changes of physiological factors of photosynthesis includes differences in the CO2 conductance, in the Calvin cycle enzymes, the capacity of electron transport, the photophosphorylation and the pigments (Boardman, 1977; Wild, 1979; Bjorkman, 1981; Lichtenthaler et al., 1981). The adaptation of individual plants or leaves to lo…

Organic Field Effect Transistors: Noncovalent Functionalization and Passivation of Black Phosphorus with Optimized Perylene Diimides for Hybrid Field…

2020

White Phosphorus Is Air-Stable Within a Self-Assembled Tetrahedral Capsule

2009

Molecular Fire Quencher Cage-shaped molecular assemblies can regulate the reactivity of smaller molecules trapped within them. Mal et al. (p. 1697 ) extend this approach to enable the protection of elemental white phosphorus (P 4 ), a substance that rapidly ignites on contact with oxygen. The tetrahedral cages self-assemble in aqueous solution through coordination of six ligands to four iron ions, and efficiently capture phosphorus from a suspension. The water-soluble host-guest constructs were stable in air for at least 4 months, but released intact P 4 rapidly on displacement by added benzene.

Darstellung eines reinen monomeren formaldehyds durch acidolytische depolymerisation von Trioxan. 22. Mitt. über polyoxymethylene1

1964

Trioxan wird mit nahezu quantitativem Umsatz kontinuierlich in einem Stickstoffstrom bei 200°C an einem Pyrophosphorsaure-Kontakt zu monomerem Formaldehyd depolymerisiert. Durch Vorpolymerisation von ca. 5% des gasformigen Formaldehyds werden die geringfugigen Verunreinigungen wie Methylformiat, Wasser und unumgesetztes Trioxan entfernt, so das das restliche Monomere eine Reinheit von mindestens 99,98% besitzt. Losungen dieses Formaldehyds in Toluol oder Diathylather zeigen zwischen –78 und –50°C eine sehr gute Haltbarkeit. Trioxane is depolymerized almost quantitatively to form monomeric formaldehyde in a flow system at 200°C. using pyrophosphoric acid as catalyst and nitrogen as a carrier…

Synthesis of new 2,2′-disubstituted 5,5′-dimethyl-4,4′-bitriazoles and 2-(4-Triazolyl)quinoxalines

2000

Thermal rearrangement of 3-acylisoxazole arylhydrazones allowed facile preparation of 2H-1,2,3-triazoles which were firstly reacted with isoamyl nitrite and then with an opportune arylhydrazine to produce the corresponding α-hydroxyiminohydrazones 8a-h. The reaction of compounds 8a-h with phosphorus pentachloride afforded the desired 4,4′-bitriazoles 1a-h. The α-hydroxyiminoketone derivative 7 or the α-diketone 14 reacted easily with 1,2-phenylenediamine to afford 1,2,3-triazoles 2a-c bearing the quinoxaline moiety at position 4. Improved yields of the quinoxalines 2a-c were obtained when 1,2-phenylenediamine was reacted with the dioxime 15.

Scintillation Measurements at Very High Solute Concentrations; Self Quenching-Structure Correlatios

1968

Abstract Measurements of the relative scintillation yields of some liquid organic systems were carried out with several highly soluble scintillator solutes. Self quenching was observed at high concentrations with some of the solutes, but not with others. The results were correlated with the ability of the solute molecules to come together, in a special configuration, close enough to form an association. A study of the atomic models of the solute molecules showed that those moleculeswith chromophor systems which were non-coplanar, or co-planar but shielded by substituent groups, did not produce self quenching. However, those solute molecules with unprotected co-planar chromophor systems did …