Cilj rada bio je utvrditi koncentraciju joda u sirovom kravljem mlijeku proizvedenom u Federaciji Bosne i Hercegovine (BiH) te procijeniti udio mlijeka u ukupnoj konzumaciji joda kod BiH populacije. ...Uzorci mlijeka prikupljeni su iz pet različitih regija tijekom proljeća, ljeta i zime. Koncentracija joda u uzorcima određena je metodom ICP-MS. Srednja vrijednost (± standardna devijacija) sadržaja joda u mlijeku iznosila je 60,9±67,5 μg/kg i varirala od 4,4 do 378,7 μg/kg. Zimsko mlijeko sadržavalo je više joda (84,0±88,2 μg/kg) nego proljetno (45,3±46,7 μg/kg) i ljetno mlijeko (51,3±51,0 μg/kg), iako u dvije od pet istraživanih regija nije postojala ovakva tendencija a sadržaj joda u mlijeku bio je sličan u sve tri sezone. Vrlo niske koncentracije joda (ispod 20 μg/kg) utvrđene su u 41 uzorku, ukazujući na raširen deficit joda kod muznih krava. Mlijeko iz sjeveroistočnog dijela zemlje imalo je znatno veći sadržaj joda nego mlijeko iz preostale četiri regije u sve tri sezone. U svim uzorcima iz te regije sadržaj joda bio je veći od 20 μg/kg. Uz trenutno postojeću prosječnu konzumaciju od 0,4 L dnevno, mlijeko sudjeluje s 20 % u preporučenom dnevnom unosu joda za ljude, varirajući od 6 % do 72 %, ovisno o sezoni godine i dijelu zemlje. Rezultati ukazuju na potrebu dodatnog obogaćivanja obroka životinja jodom, kao i na potrebu povećanja konzumacije mlijeka kod ljudske populacije.
Oxidative carbonylation of aniline to
N,N′diphenyl urea was achieved at 100°C and atmospheric pressure conditions. The screening of several homogeneous transition metal complexes was carried out. The ...best catalytic activity was shown by Ru(CO)
3I
3NBu
4 catalyst. The effect of solvents, temperature, aniline and promoter concentration etc. on the activity and selectivity of this catalyst was studied. The activation energy of the reaction is evaluated as 26.6 kcal/mol. A plausible mechanistic pathway for oxidative carbonylation of aniline to diphenyl urea has also been proposed.
This paper describes the application of an anode-support system to the electrolytic production of cuprous iodide by the anodic dissolution of metallic copper in an acidic potassium iodide solution. ...At the cathode the reduction of iodine to iodide is carried out. It has been determined that it is possible to utilize in the process an AISI-316 L stainless steel mesh basket loaded with small pieces of high-grade copper scrap. Under the operating conditions used the AISI-316 L stainless steel remains passive and acts only as an electrical contact between the copper pieces and the external current source. As cathode system, an AISI-316 L stainless steel mesh surrounded by a polypropylene diaphragm was utilized. As recommended operating conditions, a solution of KI: 40 g dm
−3 and I
2 : 20 g dm
−3, pH: 1.8±0.2, current density: 1.0 A dm
−2, T: 20±1°C, can be used. Good quality cuprous iodide powder (99.8% purity) was obtained. The energy consumption was 0.21 kWh (kg CuI)
−1.
Halogenated organic substances are among the main environmental concerns. A number of micro‐organisms are able to dehalogenate these compounds. However, the methods for the assessment of ...micro‐organismal ability to dehalogenate are expensive and require complex instrumentation. Here, an easy colorimetric assay for the screening and assessment of the ability of bacterial cultures to deiodinate, and potentially dehalogenate, chemical substances is proposed. The method is based on the oxidation of iodide, released due to biotransformation, to iodine followed by a subsequent detection of iodine by a classical reaction with starch.
Provider: Czech digital library/Česká digitální knihovna - Institution: National Medical Library/Národní lékařská knihovna - Data provided by Europeana Collections- Jaroslav Kříž- All metadata ...published by Europeana are available free of restriction under the Creative Commons CC0 1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
The leaching kinetics of chalcopyrite (CuFeS sub 2 ) in ammonium iodide solutions with iodine has been studied using the rotating disk method. The variables studied include the concentrations of ...lixiviants, rotation speed, pH of the solution, reaction temperature, and reaction product layer. The leaching rate was found to be independent of the disk rotating speed. The apparent activation energy was measured to be approx50 kJ/mole from 16-35 deg C, and 30.3 kJ/mole from 35-60 deg C. The experimental findings were described by an electrochemical reaction-controlled kinetic model: rate= kappa NH sub 3 exp 0.69 OH exp - exp 0.42 I sub 3 exp - exp 0.5 .
Der hier beschriebene Versuch kombiniert ganz verschiedene Lehrinhalte wie Extraktion und Nernstsches Verteilungsgesetz, Komplexbildung und Massewirkungsgesetz, Chemie des Iods, iodometrische ...Titration, Fehlerbetrachtung von Meßwerten sowie fachgerechte Aufbereitung von Versuchsresten. Er eignet sich besonders für ein anorganisch-analytisches Anfängerpraktikum. (Orig.).
Provider: - Institution: - Data provided by Europeana Collections- Marburg, Univ., Diss., 2009- All metadata published by Europeana are available free of restriction under the Creative Commons CC0 ...1.0 Universal Public Domain Dedication. However, Europeana requests that you actively acknowledge and give attribution to all metadata sources including Europeana
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