Radioactivity of coals and fly ashes

The level and the behavior of the naturally occurring primordial radionuclides ²³⁸U, ²²⁶Ra, ²¹⁰Pb, ²³²Th, ²²⁸Ra and ⁴⁰K in coals and fly ashes are described. The activity concentrations of the examined coals and originated from coal mines in Greece ranged from 117 to 435 Bq·kg⁻¹ for ²³⁸U, from 44 to 255 Bq·kg⁻¹ for ²²⁶Ra, from 59 to 205 Bq·kg⁻¹ for ²¹⁰Pb, from 9 to 41 Bq·kg⁻¹ for ²²⁸Ra and from 59 to 227 Bq·kg⁻¹ for ⁴⁰K. These levels are comparable to those appeared in coals of different countries worldwide. The activity concentrations of the examined fly ashes and produced in coal-fired power plants in Greece ranged from 263 to 950 Bq·kg⁻¹ for ²³⁸U, from 142 to 605 Bq·kg⁻¹ for ²²⁶Ra, from 133 to 428 Bq·kg⁻¹ for ²¹⁰Pb, from 27 to 68 Bq·kg⁻¹ for ²²⁸Ra and from 204 to 382 Bq·kg⁻¹ for ⁴⁰K. The results showed that there is an enrichment of the radionuclides in fly ash relative to the input coal during the combustion process. The enrichment factors (EF) ranged from 0.60 to 0.76 for ²³⁸U, from 0.69 to 1.07 for ²²⁶Ra, from 0.57 to 0.75 for ²¹⁰Pb, from 0.86 to 1.11 for ²²⁸Ra and from 0.95 to 1.10 for ⁴⁰K.     

Radiological characterization of phosphate fertilizers: Comparison between alpha and gamma spectrometry

The natural radioactivity in phosphate fertilizers used in central Italy has been measured by alpha and gamma spectrometry. The results show that the specific activities of ²³⁸U, ²³⁴U and ²³⁵U ranged within interval from < 0.5 to 2628.8, from < 0.5 to 2826.3 and from < 0.9 to 138.0 Bq kg^{− 1} respectively and those of ²¹⁰Pb and ²¹⁰Po ranged within interval from < 15.0 to 401.5 and < 0.5 to 351.6 Bq kg^{− 1} respectively. The ²²⁸Th, ²³⁰Th and ²³²Th concentrations found by alpha spectrometry ranged from < 0.5 to 50.2, from 0.9 to 2727.2 and from < 0.5 to 60.8 Bq kg^{− 1} respectively. ²²⁶Ra and ²²⁸Ra activity concentrations ranged from < 14.3 to 290.9 and from < 2.9 to 24.9 respectively. ⁴⁰K specific activities ranged from 39.2 to 8263.7 Bq kg^{− 1}. A very good correlation exists between the activity concentrations found by alpha spectrometry and those found by gamma spectrometry.     

Microdistributions of Electrolytic Alloys and Their Components

Microdistributions of Cu–Ni and Cu–Co alloys electrodeposited from pyrophosphate; Ni–Cu, from sulfate–chloride and pyrophosphate–ammonium; Cu–Zn, from pyrophosphate and cyanide; Cu–Cd, from sulfate and pyrophosphate; and Ni–Cd, Ni–Co–Cd, and Zn–Cd, from sulfate, sulfate–chloride, pyrophosphate, chloride–ammonium, and acetate electrolytes are studied. The coatings' microprofile depends on the kinetics of reduction of each component and mutual influence of electrochemical processes at the cathode. Copper accelerates and cadmium inhibits the reduction of the second component of alloys, no matter the electrolyte type, reduction kinetics, and metal nature. In antileveling conditions, the diffusion-controlled Cu reduction accelerates the reduction of the second component of alloys and ensures deposition of coatings whose microprofiles are more uniform than expected from diffusion limitations only. Depolarizing action of Cu during the Cu–Zn deposition from a cyanide electrolyte can completely neutralize differences in the rates of supply of reduced metal ions; hence a constant chemical composition of the coating over its microprofile. Inhibiting action of the diffusion-controlled Cd deposition provides for leveling properties of electrolytes from which Ni–Cd, Ni–Co–Cd, and Zn–Cd alloys are deposited; the chemical composition of these deposits is nonuniform over their microprofiles.     

Trace metal analyses in honey samples from selected countries. A potential use in bio-monitoring

Honey is a sweet product made by bees using nectar from flowers. Concentrations of Ca, K, Mg, Fe, Zn, Mn, Cu, Pb and Cd were determined in 13 honey samples from the selected regions around the world. Levels of Ca, Mg, Cu, Fe, Zn and Mn were measured using flame atomic absorption spectrometry (FAAS). Potassium concentration was determined via flame photometry. Concentrations of Cd and Pb were determined using the electrothermal technique (ETAAS). It was estimated that the examined samples of honey from Greece, Turkey, Spain, Poland, Mexico, Argentina and Italy were of good quality in terms of metal concentrations (compliant with the norms referring to food products – WHO, Fifty-third Report of the joint FAO/WHO Expert Committee on Food Additives; Technical Report Series 776, Geneva), although the analysed samples were not free of heavy metals. The concentrations of the elements in the honey samples ranged from 2.38 to 9.31 μg · g^?1 for Zn, from 3.86 to 35.10 μg · g^?1 for Fe, from 0.19 to 21.64 μg · g^?1 for Mn, from 49.53 to 1006.90 μg · g^?1 for Ca, from 388.25 to 4761.50 μg · g^?1 for K and from 0.20 to 1.53 μg · g^?1 for Cu and regarding heavy metals from 0.11 to 2.78 μg · g^?1 for Pb and from 0.02 to 0.44 μg · g^?1 for Cd. According to these results it was found that the concentrations of heavy metals in the honey samples (except for alfalfa honey and eucalyptus honey from Italy) were under the acceptable limits for foods set out by the FAO/WHO. It was confirmed that the application of chemometric tools supports the extraction of significant information from analytical data, even though the availability of samples is not fully sufficient (this problem is often encountered in environmental analyses).     

Identification des composés phénoliques dans les feuilles de Homogyne alpina,Petasites albus,Petasites hybridus et Adenostyles alliariae

Four polyphenolheterosides have been isolated from the leaves of Homogyne alpina, Petasites albus, Petasites hybridus and Adenostyles alliariae by means of thin layer and column chromatography on polyamide. Isoquercitrine (II) has been isolated from Petasites albus, Petasites hybridus and Adenostyles alliariae; Astragaline (III) from Petasites albus and Petasites hybridus; Glucoluteoline (IV) from Adenostyles alliariae and Rutine (I) from Homogyne alpina. Piceine (V) has also been isolated from Homogyne alpina.     

HPLC Fingerprint Characteristics of Active Materials of Garlic and Other Allium Species

The bioactive molecules of garlic are classified according to their enzymatic activities as either alliinase activators or alliinase inactivators. The alliinase activation reaction system is mainly composed of sulfur-containing compounds, whereas the alliinase inactivation system is mainly composed of amino acid-based materials. The purpose of this study was to develop an effective way to digitally express features of complex active compounds of garlic as a basis for quality control. HPLC was used to develop the fingerprints of plants from different Allium species and different geographical regions according to whether the compounds were sulfur containing or based on amino acids. Using the Shannon equation, I values of sulfur-containing compounds from garlic ranged from 3.55 to 3.94, whereas I values of sulfur-containing compounds from other Allium plants, onions, leek, and Welsh onion, ranged from 3.38 to 3.53. The I values of amino acid-based compounds from garlic ranged from 3.67 to 3.91, whereas I values of these compounds from other Allium plants ranged from 3.88 to 3.99. This method effectively distinguished garlic from different species of Allium plants. This method also provided a way to digitally monitor the presence of complex active compounds of garlic and may allow evaluation of quality. This method may also provide a theoretical basis for quality control of bioactive compounds from other medicinal plants.     

Comparison of the nutritional and phytochemical composition and antioxidant activities of Aralia elata (Miq.) Seem fruits in Northeast China

Aralia elata (Miq.) Seem is a wild medicinal and culinary plant. The newly grown shoots are edible, and the stem and root bark are traditional materials used for medicinal extraction. However, few studies have examined the quality and biological activity of the fruit. In this study, we compared the nutritional and phytochemical composition and antioxidant activity of A. elata fruit (AF) picked from five regions (Harbin, Benxi, Raohe, Jiaohe, and Mudanjiang) in Northeast China. AF picked from Harbin had the highest saponin, anthocyanin, and flavonoid contents. UHPLC-MS/MS analyses showed that araloside A was one of the main saponin monomers in AF. The highest arloside A concentration was detected in fruits picked from Harbin and the lowest concentration was detected in fruits picked from Benxi. The relative reactive oxygen species production in cells after pretreatment with AFs from Harbin (50 μg/mL) was 0.78 ± 0.01, second only to those from Raohe. AFs (50 μg/mL) from Harbin had the highest catalase activity (43.61 ± 0.44 U/mg protein), followed by that of the AF collected from Jiaohe, Benxi, Mudanjiang and Raohe. The malondialdehyde levels of the AFs (50 μg/mL) obtained from Benxi, Raohe, Jiaohe, and Mudanjiang were significantly higher than those of the AF obtained from Harbin (2.67 ± 0.15 nmol/mg protein). Compared with AFs from Benxi, Raohe, Jiaohe, and Mudanjiang, the strongest H₂O₂ scavenging ability (144.95 ± 2.89 mmol TE/100 g dm) was observed for AF from Harbin. The ferric reducing antioxidant power of AFs ranged from 7.70 to 4.52 mmol TE/100 g dm in the order of Harbin > Mudanjiang > Raohe > Jiaohe > Benxi. The results provided support for the selection of the best quality AF and the expanded cultivation of A. elata.     

Separation of Anions and Cations on Thorium Tellurite-A New Amphoteric Ion Exchanger

Abstract

A new amphoteric ion exchanger, thorium tellurite has been synthesized. Its chemical stability, composition determination and potentiometric titration have been performed. K_d values for various anions and cations have been determined. The material was found useful for separation of NO₃ ^? from NO₂ ^?; MoO₄ ^2? from PO₄ ^3?, VO₃ ^? from MeO₄ ^2?, SO₄ ^2? from S₂O₃ ^2? and BrO₃ ^? from Br^? and also of Cu(II) from Hg(II), Cu(II) from Ni(II), Pb(II) from Cd(II) and UO₂(I) from Hg(II).     

Stable nitroxide radicals. Reaction between 2-cyano- and 4-cyanobenzoquinoline N-oxides and the grignard reagent

2,2-Diphenylbenzoquinolinenitroxide radicals were obtained starting from 2-phenyl-, 2-cyano, 4-cyano-benzoquinoline N-oxides, or from unsubstituted benzoquinoline N-oxides with phenylmagnesium bromide. The elimination of bromomagnesium hydride from the 2-unsubstituted benzoquinoline N-oxides and cyanomagnesium bromide from the 2- or 4-cyanobenzoquinoline N-oxides is discussed.     

Mechanism of dehydrodimerization of aromatic substrates by aluminium chloride-cupric chloride

The following results were obtained from oxidation of the appropriate aromatic hydrocarbons with AlCl₃-CuCl₂: 1-(2,4,6-trimethylphenyl)naphthalene from naphthalene-meistylene, 2,2'-bifluorene from nuorene, 2,2'-bifluorene from fluorene-mesitylene, and bimesityl and 3,3'-dichlorobimesityl from mesitylene. Mechanistically, radical cations are presumed to function as intermediates. Generally, coupling seems to proceed by cation attack on an aromatic molecule. Other pathways may pertain in certain cases, e.g. radical dimerization of radical cations.     

Uncertainty of decay heat calculations originating from errors in the nuclear data and the yields of individual fission products

The calculation of the abundance pattern of the fission products with due account taken of feeding from the fission of²³⁵U,²³⁸U, and²³⁹Pu, from the decay of parent nuclei, from neutron capture, and from delayed-neutron emission is described. By means of the abundances and the average beta and gamma energies the decay heat in nuclear fuel is evaluated along with its error derived from the uncertainties of fission yields and nuclear properties of the individual fission products.     

Synergic effect studies of the bi-enzymatic system laccase-peroxidase in a voltammetric biosensor for catecholamines

Several bi-enzymatic carbon paste biosensors modified with enzymes laccase from Pleurotus ostreatus fungi and peroxidase from zucchini (Cucurbita pepo) were constructed for evaluating the synergic effect of the two enzymes on the voltammetric biosensor response for various catecholamines. Initially was investigated the effect of pH from 5.0 to 7.5, temperature from 25 to 50 °C, initial stirring time from 30 to 150 s, scan rate from 10 to 60 mV s⁻¹ and potential pulse amplitude from 10 to 60 mV on the biosensor response for several catecholamines such as dopamine, adrenaline, isoprenaline and l-dopa. It was observed a biosensor signal increase employing both enzymes, indicating thus there is a synergic effect between laccase and peroxidase, verified also in spectrophotometric studies, in the determination of these catecholamines.     

The Positional δ(18O) Values of Extracted and Synthetic Vanillin

The positional δ(¹⁸O) values of vanillin ( 1 ) of different origins have been determined from the global values of 2‐methoxy‐4‐methylphenol ( 4 ), obtained from 1 upon Clemensen reduction, and of 3‐methylanisole ( 5 ), obtained from 4 by removal of the phenolic O‐atom. By these means, it is possible to differentiate samples of 1 of synthetic origin from those extracted from Vanilla plants or produced from lignin by chemical oxidation. The main difference between the samples derived from guaiacol and those possessing the aromatic moiety of natural origin is in the enrichment values of the O‐atoms at C(3) and C(4), while the extractive materials from the pods are distinguished from the product from lignin on the basis of the carbonyl oxygen δ(¹⁸O) values, ranging from +25.5 and +26.2 in the natural material to +19.7‰ in the lignan‐based sample. The values for the phenolic O‐atom vary from +8.9 and +12‰ of the synthetic materials to +6.5, +5.3, and +6.3‰, respectively, of the sample from lignin and the two samples from Vanilla pods,whereas the MeO O‐atoms show the following values for the same compounds: −2.9, −3.2, +3.5, +3.1, and +2.3‰, respectively. This study indicates the significance of the positional δ(¹⁸O) values of polyoxygenated compounds for the definition of their origin.     

Uranium isotopes as a tracer of groundwater transport studies

The activity concentrations of ²³⁴U and ²³⁸U in thermal groundwater, deep well water and river water samples from Central Poland were determined. Concentration of ²³⁴U and ²³⁸U in the examined waters varied from <0.013 (LLD) to 16.8 mBq/dm³ and from <0.013 (LLD) to 45.5 mBq/dm³ respectively. The highest uranium activity concentrations were measured in the thermal groundwater from Mszczonow and Cieplice, while the lowest were observed in thermal ground water from Uniejow and Poddebice. In thermal groundwater from Skierniewice, uranium activity concentrations were below lower limit of detection (0.013 mBq/dm³). The ²³⁴U/²³⁸U activity ratio varied from 0.37 (Cieplice) to 1.30 (Poddebice well water).     

Observation of the phosphorescence spectra from the spin sublevels of low emissivity: quinoxaline

A method to observe the phosphorescence emissions from the spin sublevels of low emissivity is proposed, and its application to quinoxaline is attempted. The newly observed phosphorescence spectra from the T_x and T_y sublevels differ considerably in vibrational structures from the usually observed phosphorescence from the T_z sublevel.     

A Rapid Method for the Analysis of Ten Compounds in Psoralea corylifolia L. by UPLC

The objective of this study was to develop a simple, efficient and reliable method for routine quantitative analysis for Psoralea corylifolia L. An ultra performance liquid chromatography with DAD detector system was employed for simultaneous quantification of ten compounds. The chromatographic analysis was performed by UPLC with C₁₈ column and gradient elution of 0.05% formic acid aqueous solution and acetonitrile in 16 min. All calibration curves were linear (R ² ≥ 0.9990) over the tested ranges. The LOD and LOQ were lower to 13.07 and 39.22 ng mL^?1 with 2 μL of injection volume, respectively. The intra- and inter-day precisions as determined from sample solutions were below 4.1 and 4.2%. The average recoveries were ranged from 94.2 to 108.8% with RSDs ≤ 4.6%. This validated method was applied for the analysis of ten analytes in P. corylifolia L. from different origins. The variation of the content of ten compounds was remarkable among the tested samples: psoralenoside increased from 7.42 to 17.04 mg g^?1, isopsoralenoside from 6.05 to 14.34 mg g^?1, psoralen from 2.37 to 3.90 mg g^?1, isopsoralen from 2.53 to 3.65 mg g^?1, neobavaisoflavone from 1.59 to 2.96 mg g^?1, bavachin from 1.02 to 2.35 mg g^?1, psoralidin from 0.45 to 1.91 mg g^?1, isobavachalcone from 1.33 to 4.71 mg g^?1, corylifol A from 1.02 to 2.40 mg g^?1 and bakuchiol from 28.10 to 63.89 mg g^?1.     

Determination of Natural Vitamin E from Italian Hazelnut Leaves

A new potential source of natural vitamin E from thirteen samples of Corylus avellana L. leaves was screened: the major Italian cultivar — Tonda romana (collected from Latium and Sardinia localities); ten local genotypes from Sardinia — Moro seme, Suconcale, Moro, Sarda grossa, Sarda grossa seme, Sarda schiacciata, Coccoredda, Sarda lunga, Sarda piccola and Sarda tardiva; wild genotype — Selvatico from Latium. The determination was performed after optimizing the high-efficiency pressurized liquid extraction (PLE) conditions of α-tocopherol from Italian hazelnut tree green leaves. Moro from Sardinia showed the highest content of α-tocopherol (237.4±0.3 μg/g d.w). Leaves of this genotype may be considered as a potential new source for natural α-tocopherol. __________ Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 538–540, November–December, 2005.     

Determination of uranium and thorium in complex samples using chromatographic separation, ICP-MS and spectrophotometric detection

The paper describes a research of possible application of UTEVA and TRU resins and anion exchanger AMBERLITE CG-400 in nitrate form for the isolation of uranium and thorium from natural samples. The results of determination of distribution coefficient have shown that uranium and thorium bind on TRU and UTEVA resins from the solutions of nitric and hydrochloric acids, and binding strength increases proportionally to increase the concentration of acids. Uranium and thorium bind rather strongly to TRU resin from the nitric acid in concentration ranging from 0.5 to 5 mol L⁻¹, while large quantities of other ions present in the sample do not influence on the binding strength. Due to the difference in binding strength in HCl and HNO₃ respectively, uranium and thorium can be easily separated from each other on the columns filled with TRU resin. Furthermore, thorium binds to anion exchanger in nitrate form from alcohol solutions of nitric acid very strongly, while uranium does not, so they can be easily separated. Based on these results, we have created the procedures of preconcentration and separation of uranium and thorium from the soil, drinking water and seawater samples by using TRU and UTEVA resins and strong base anion exchangers in nitrate form. In one of the procedures, uranium and thorium bind directly from the samples of drinking water and seawater on the column filled with TRU resin from 0.5 mol L⁻¹ HNO₃ in a water sample. After binding, thorium is separated from uranium with 0.5 mol L⁻¹ HCl, and uranium is eluted with deionised water. By applying the described procedure, it is possible to achieve the concentration factor of over 1000 for the column filled with 1 g of resin and splashed with 2 L of the sample. Spectrophotometric determination with Arsenazo III, with this concentration factor results in detection limits below 1 μg L⁻¹ for uranium and thorium. In the second procedure, uranium and thorium are isolated from the soil samples with TRU resin, while they are separated from each other on the column filled with anion exchanger in alcohol solutions. Anion exchanger combined with alcohol solutions enables isolation of thorium from soil samples and its separation from a wide range of elements, as well as spectrophotometric determination, ICP-MS determination, and other determination techniques.     

Analysis of high molecular weight esters and ketones in thymus

A crystalline mixture of esters from Thymus chamaedris is analyzed by mass spectrometry, and after hydrolysis, by gas chromatography. Two series of straight chain even aliphatic acids from C₁₆ to C₂₆, and from C₄₀ to C₄₈, and a series of straight chain even saturated primary alcohols, from C₈ to C₃₀, are its main constituents. Another crystalline mixture, isolated from Thymus caespititius, is shown by mass spectrometry and gas chromatography to be composed of a straight chain series of aliphatic ketones, from C₂₅ to C₃₇.     

Natural radioactivity in soil samples of Kocaeli basin, Turkey

The city of Kocaeli is in the western part of Anatolia in Turkey and has a population of approximately 1.000.000. There is no information about radioactivity in the Kocaeli soils samples so far. For this reason, the concentrations of the natural radionuclides in soil samples from 27 different sampling stations in Kocaeli Basin and its surroundings have been determined. The results have been compared with other radioactivity measurements in different country"s soils. The typical concentrations of ¹³⁷Cs, ²³⁸U, ⁴⁰K, ²²⁶Ra, ²³²Th found in surface soil samples ranged from 2±0.6 to 25±6 Bq/kg, from 11±4 to 49±10 Bq/kg, from 161±30 to 964±127 Bq/kg, from 10±4 to 58±11 Bq/kg, and from 11±3 to 65±13 Bq/kg, respectively.