Search results for "PET"

showing 10 items of 12749 documents

Untersuchungen zur biologischen Aktivität der Phenylborsäure

1961

After 10 applications of phenylboric acid (0.03 ml of a 2·10−3 M solution) to young plants ofKalanchoe blossfeldiana the flowers were found to have a reduced number of petals or no petals at all. InCucumis sativus one application of phenylboric acid at the same strength was enough to cause abnormal flowers to develop in the axils of 8 to 10 leaves; in addition there were 1 to 2 leafles nodes and other abnormalities. The position of the abnormal flowers and leafless nodes was dependant upon the stage of development of the plant at the time of application. It seems from a parallel study of treated plants grown to maturity, and plants sectioned at the time of treatment, that phenylboric acidin…

ChemistryBotanyGeneticsParallel studyPrimordiumPetalPlant SciencePlanta
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Modelling of thermo-chemical properties over the sub-solidus MgO–FeO binary, as a function of iron spin configuration, composition and temperature

2014

Thermo-chemical properties and T–X phase relations diagram of the (Mg,Fe)O solid solution are modelled using mixing Helmholtz energy, ΔF(T,x)mixing, calculated by quantum mechanical and semi-empirical techniques. The sub-solidus MgO–FeO binary has been explored as a function of composition, with iron either in high-spin (HS) or low-spin (LS) configuration. Only the HS model provides physically sound results at room pressure, yielding a correct trend of cell edge versus composition, whereas LS’s issues are at variance with observations. Mixing Helmholtz energy has been parametrized by the following relationship: ΔF(T,x)mixing = x × y × [U0(T) + U1(T) × (x – y) + U2(T) × (x − y)2]−T × S(x,y)c…

ChemistryDegrees of freedom (physics and chemistry)(MgFe)OThermodynamicsSolidusMixing energyGibbs free energyMixing energy; Ab initio and semi-empirical modelling; (Mg; Fe)Osymbols.namesakeCrystallography(MgFe)O; Ab initio and semi-empirical modelling; Mixing energy; Geochemistry and Petrology; Materials Science (all)Geochemistry and PetrologyPhase (matter)Helmholtz free energysymbolsRelaxation (physics)General Materials ScienceMaterials Science (all)(MgFe)OAb initio and semi-empirical modellingMixing (physics)Solid solutionPhysics and Chemistry of Minerals
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FeMnOx-1: A new microanalytical reference material for the investigation of Mn–Fe rich geological samples

2016

Suitable Mn-Fe rich microanalytical reference materials (MRMs) as calibration material for laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) have not been available. The United States Geological Survey (USGS) in collaboration with the Max Planck Institute for Chemistry has prepared a synthetic MRM, FeMnOx-1, with elevated mass fractions of MnO (25 g/100 g), Fe2O3 (8.5 g/100 g) and high mass fractions of 25 trace elements varying between 200 and 5000 mg/kg. This new MRM has been designed as calibration material for a wide range of different Mn-Fe deposits, such as desert/rock varnish, ocean crusts and nodules as well as Mn accumulations in soils and lakes. Small-scale an…

ChemistryDesert varnish010401 analytical chemistryAnalytical chemistrychemistry.chemical_elementGeologyManganese010502 geochemistry & geophysicsMass spectrometryLaser01 natural sciencesMicroanalysis0104 chemical scienceslaw.inventionGeochemistry and PetrologylawHomogeneity (physics)Soil waterMass fraction0105 earth and related environmental sciencesChemical Geology
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Geochemical characteristics of waters in mineralised area of Peloritani Mountains (Sicily, Italy)

2009

Abstract This paper presents the results of a study on the geochemistry of waters circulating in the mineralised area of the south-eastern sector of Mt. Peloritani (north-eastern Sicily, Italy), aimed at basic understanding of the geochemical processes influencing their chemical composition. Chemico-physical parameters and data on 26 major and minor chemical elements are reported for 103 water samples. Water chemistry is mainly dominated by dissolution of carbonates and hydrolysis of aluminosilicate minerals. Total dissolved salts (TDS) range from 80 to 1398 mg/L. All the waters exhibit E H characteristic of an oxygenated environment. Excluding two samples, which show very high H + activity…

ChemistryDolomiteCarbonate mineralsGeochemistryTrace elementWeatheringPollutionSettore GEO/08 - Geochimica E Vulcanologiachemistry.chemical_compoundmineralised area trace elements hydrogeochemistryGeochemistry and PetrologyEnvironmental ChemistryKaoliniteCarbonateClay mineralsChemical compositionApplied Geochemistry
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Sicilian bottled natural waters: Major and trace inorganic components

2013

Sixteen bottled waters of various Sicilian brands, 11 natural mineral waters and five normal drinking waters, were analyzed for major and trace inorganic components by ion chromatography (IC) and inductively coupled plasma-mass spectrometry (ICP-MS), respectively. The bottled waters represent a variety of water types with significantly different compositions in terms of salinity, major components and trace elements. Chemically, they range from Ca–HCO3 and Ca–SO4 to Na–HCO3 types. Total dissolved solids ranges from 54 to 433 mg/L, total hardness from 25 to 238 mg/L CaCO3, and measured Na content from 5.7 to 57 mg/L. According to total dissolved ions, all the bottled waters were classified as…

ChemistryIon chromatographyBottled waterMass spectrometryTotal dissolved solidsPollutionSettore GEO/08 - Geochimica E VulcanologiaSalinityNutrientGeochemistry and PetrologyEnvironmental chemistryEnvironmental ChemistryWater qualitybottled natural waters major and trace elements municipal watersChemical compositionApplied Geochemistry
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Mn3+ in garnets III. Absence of Jahn-Teller distorition in synthetic Mn3+-bearing garnet

1985

The crystal structure of a ternary Mn3+-bearing garnet, close to the composition Gross34 Spess26 CaMnGt40 has been refined to a weighted R-value of 0.051 for 440 unique reflections. The lattice constant is 11.867(1) A, fractional atomic parameters for oxygen are x=0.0374 (2), y=0.0470 (2), and z=0.6532 (2). Refinement of site occupancies gave 0.81 (3) Ca+0.19 (3) Mn2+ in the eight coordinated site 24c and 0.64 (2) Al+0.36 (2) Mn3+ in the octahedral site 16a. No deviation from the cubic space group Ia3d has been observed, the Mn3+-bearing YO6 octahedron is nearly regular. Thus, the presence of the 3d 4-configurated ion Mn3+ does not cause Jahn-Teller distortion in this garnet structure.

ChemistryJahn–Teller effectMineralogychemistry.chemical_elementCrystal structureOxygenIonCrystallographyLattice constantOctahedronGeochemistry and PetrologyGroup (periodic table)General Materials ScienceTernary operationPhysics and Chemistry of Minerals
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Structure and stability of hexadentate complexes of ligands based on AAZTA for efficient PET labelling with gallium-68

2012

Pre-organised tricarboxylate ligands based on 6-amino-perhydro-1,4-diazepine bind (68)Ga rapidly and selectively in acetate buffer at pH 4 to 7, forming kinetically stable complexes suitable for use in PET imaging.

ChemistryMetals and Alloyschemistry.chemical_elementGeneral ChemistryPet imagingTricarboxylateCombinatorial chemistryCatalysisSurfaces Coatings and FilmsElectronic Optical and Magnetic MaterialsLabellingMaterials ChemistryCeramics and CompositesOrganic chemistryGalliumChem. Commun.
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Comparison of different phosphorus-containing ligands complexing 68Ga for PET-imaging of bone metabolism

2010

Abstract 99mTc-phosphonate structures are well established tracers for bone tumour imaging. Our objective was to investigate different 68Ga-labelled phosphonate ligands concerning labelling kinetics, binding to hydroxyapatite and bone imaging using μ-PET. Seven macrocyclic phosphorus-containing ligands and EDTMP were labelled in nanomolar scale with n.c.a. 68Ga in Na-HEPES buffer at pH∼4. Except for DOTP, all ligands were labelled with >92% yield. Binding of the 68Ga-ligand complexes on hydroxyapatite was analysed to evaluate the effect of the number of the phosphorus acid groups on adsorption parameters. Adsorption of 68Ga-EDTMP and 68Ga-DOTP was >83%. For the 68Ga-NOTA-phosphonates …

ChemistryPhosphorus containingComplex formationOrganic chemistryPet imagingPhysical and Theoretical ChemistryBone remodelingRadiochimica Acta
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Contrasting evolution of iron phase composition in soils exposed to redox fluctuations

2018

Abstract Ferric iron (FeIII) solid phases serve many functions in soils and sediments, which include providing sorption sites for soil organic matter, nutrients, and pollutants. The reactivity of Fe solid phases depends on the mineral structure, including the overall crystallinity. In redox-active soils and sediments, repeated reductive dissolution with subsequent exposure to aqueous ferrous iron (Fe2+) and oxidative re-precipitation can alter Fe phase crystallinity and reactivity. However, the trajectory of Fe mineral transformation under redox fluctuations is unclear and has been reported to result in both increases and decreases in Fe phase crystallinity. Several factors such as water bu…

ChemistrySoil organic matterSoil classification04 agricultural and veterinary sciences010501 environmental sciences01 natural sciencesFerrousAndosolCrystallinityGeochemistry and PetrologyEnvironmental chemistrySoil water040103 agronomy & agriculture0401 agriculture forestry and fisheriesLeaching (agriculture)Dissolution0105 earth and related environmental sciencesGeochimica et Cosmochimica Acta
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Size variation and cell proliferation in chemosensory brain areas of a lizard (Podarcis hispanica): effects of sex and season

2008

Many lizards rely on chemoreception for crucial aspects of their biology, including exploration, prey and predator detection, and intraspecific communication. Here we investigate sex and seasonal variation in size and proliferative activity in chemosensory areas of the lizard brain. We captured adult Iberian wall lizards (Podarcis hispanica) of either sex in the breeding (April) and non-breeding (November) season, injected them with 5-bromo-2'-deoxyuridine (BrdU) and killed them 3 weeks later. We removed the brains, measured the length of the olfactory bulbs, and counted BrdU-labelled cells in the main and accessory olfactory bulbs (MOB, AOB), lateral cortex (LC) and nucleus sphericus (NS).…

ChemoreceptorbiologyLizardGeneral NeuroscienceZoologyAnatomybiology.organism_classificationPodarcis hispanicaIntraspecific competitionSexual dimorphismbiology.animalBrain sizePredatorSex characteristicsEuropean Journal of Neuroscience
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