Search results for "Concentration"
showing 10 items of 1906 documents
Synthesis, Characterization, and Cu(2+) Coordination Studies of a 3-Hydroxy-4-pyridinone Aza Scorpiand Derivative.
2016
The synthesis, acid-base behavior, and Cu(2+) coordination chemistry of a new ligand (L1) consisting of an azamacrocyclic core appended with a lateral chain containing a 3-hydroxy-2-methyl-4(1H)-pyridinone group have been studied by potentiometry, cyclic voltammetry, and NMR and UV-vis spectroscopy. UV-vis and NMR studies showed that phenolate group was protonated at the highest pH values [log K = 9.72(1)]. Potentiometric studies point out the formation of Cu(2+) complexes of 1:2, 2:2, 4:3, 1:1, and 2:1 Cu(2+)/L1 stoichiometries. UV-vis analysis and electrochemical studies evidence the implication of the pyridinone moieties in the metal coordination of the 1:2 Cu(2+)/L1 complexes. L1 shows …
Determination of boron concentration in blood and tissue samples from patients with liver metastases of colorectal carcinoma using Prompt Gamma Ray A…
2010
As part of the studies on Boron Neutron Capture Therapy at the University of Mainz, Germany, a clinical trial has been started, in which our patients suffering from liver metastases of colorectal carcinoma, have been enrolled. Specimens of blood and healthy tissue samples taken from the patients were measured at the PGAA facilities at the HFR in Petten, The Netherlands, and at the FRM II in Munich, Germany. From the measured boron concentrations, pharmacokinetic curves and blood-to-tissue concentration ratios were produced.
Effect of gases on biochemical stabilization
2019
International audience; Lipid or protein are sensitive to peroxidation and inert gas limit or stop adulterations. Unsaturated lipids are peroxided by ground state dioxygen in presence of catalysts (iron, enzymes) or after thermal dissociation of C=C bond, and by excited state dioxygen without any assistance (photo-oxidation). Inerting fragile oils by bubbling with dinitrogen or carbon dioxide that are soluble gas in oil slows oxidation process during storage or frying. In a same way, limit the oxidation of the tryptophan residues of protein is possible by reducing oxygen content. Oxidation leads also to oxidation of thiol in disulfide, which induced protein cross-linked and decay of functio…
Synthesis, characterization and antimicrobial activity of palladium(II) complexes with some alkyl derivates of thiosalicylic acids: Crystal structure…
2012
Abstract S-Alkyl (R = benzyl, methyl, ethyl, propyl and butyl) derivatives of thiosalicylic acid and the corresponding palladium(II) complexes were prepared and their structures were proposed on the basis of infrared, 1H and 13C NMR spectroscopy. The cis geometrical configurations of the isolated complexes were proposed on the basis of an X-ray structural study of the bis(S-benzyl-thiosalicylate)–palladium(II), [Pd(S-bz-thiosal)2] complex. Antimicrobial activity of the tested compounds was evaluated by determining the minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) in relation to 26 species of microorganisms. The tested ligands, with a few exceptions, sho…
Novel supramolecular affinity materials based on (−)-isosteviol as molecular templates
2013
The readily available ex-chiral-pool building block (−)-isosteviol was combined with the C3-symmetric platforms hexahydroxytriphenylene and hexaaminotriptycene providing large and rigid molecular architectures. Because of the persistent cavities these scaffolds are very potent supramolecular affinity materials for head space analysis by quartz crystal microbalances. The scaffolds serve in particular as templates for tracing air-borne arenes at low concentration. The affinities of the synthesized materials towards different air-borne arenes were determined by 200 MHz quartz crystal microbalances.
Milk as an Essential Source of Iodine in Latvian Population
2017
Abstract Milk and dairy products are studied as alternative iodine sources, because salt iodisation is controversial due to high salt consumption leading to cardiovascular diseases. However, the iodine concentration in milk markedly varies. This study evaluated the iodine concentration in cow’s milk available in the Latvian market. Iodine and fat concentration was analysed with a spectrophotometer “Varian Cary 50” based ISO 2446:2008 in 20 milk samples. Data from the Central Statistical Bureau and survey among pregnant women were used to analyse milk product consumption and its impact on iodine status. Average iodine concentration in milk samples was 457.6 (179.6) μg/L, winter samples had a…
MEASURING REGIONAL CONVERGENCE - AN APPLICATION TO THE EUROPEAN UNION AND ROMANIA
2012
Attention of regional economic convergence has a great place in economics literature. The application of spatially explicit methods of data analysis to the convergence question has yielded important insights on regional economic growth. The literature on regional income inequality, although somewhat older than the convergence literature, has been slower to adopt new spatially explicit methods of data analysis. Application of recently developed methods of spatial econometrics to the question of regional convergence has yielded a more comprehensive and multidimensional view of regional economic growth. This article aims to identify the techniques and methods use for regional convergence and i…
Joda deficīts grūtniecēm teritoriālā griezumā un tā ietekme uz intelektuālo attīstību bērniem Latvijā
2015
Latvijā ilgstoši pastāv joda deficīts, kas ir bīstams sabiedrības veselībai un intelektuālajai attīstībai. Pat neliels joda deficīts grūtniecības periodā izraisa bērna IQ pazemināšanos, līdz ar to vēlāk arī iespējamu valsts IKP per capita samazināšanos. Uzdevumi: izvērtēt joda pietiekamību Latvijas grūtniecēm reģionālā griezumā, sakarības ar saistītiem faktoriem, kā arī censties identificēt sakarību starp joda koncentrāciju urīnā (JU) skolēniem un atzīmēm valsts eksāmenos. Visos Latvijas reģionos grūtniecēm konstatēts joda deficīts (mediānā JU 64.5-89.9 µg/g Cr). Starp grūtnieču JU un jodu saturošu vitamīnu lietošanu statistiski ticama sakarība atrasta tikai Zemgalē, bet ar jodsāls lietošan…
EXPERIMENTAL INVESTIGATION OF DILUTE SOLID-LIQUID SUSPENSION IN AN UNBAFFLED STIRRED VESSELS BY A NOVEL PULSED LASER BASED IMAGE ANALYSIS TECHNIQUE
2009
The availability of experimental information on solid distribution inside stirred tanks is a topic of great importance in several industrial applications. The measurement of solid particle distribution in turbulent multiphase flow is not simple and the development of suitable measurement techniques is still in progress. In this work a novel non-intrusive technique for measuring particle concentration fields in solid-liquid systems is employed. The technique makes use of a laser sheet, a high sensitivity digital camera for image acquisition and a Matlab procedure for post-processing the acquired images. Experimental data are here obtained for the case of an unbaffled stirred tank. Stable tor…
An Approach to Delineate Groundwater Bodies at Risk: Seawater Intrusion in Liepāja (Latvia)
2018
Groundwater quality in coastal areas is frequently affected by seawater intrusion as a consequence of intensive water consumption. To achieve “good chemical status” of a groundwater body according to Water Framework Directive the effects of saline or other intrusions should not be observed. Groundwater pumping in former decades has caused a significant seawater intrusion into confined aquifer in Liepāja and has led to deterioration of relatively wide coastal area of the third largest city in Latvia. However, the area affected by seawater intrusion is a small part of groundwater body F1 which overall chemical status is good. Thus, no specific management measures have been applied to explore …