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Introduction Linear alkylbenzenes (LABs) are used in the production of the detergents. The formation of the LABs is carried out by the alkylation of benzene with long chain olefins (C 10 –C 14 ), in the presence of AlCl 3 , HF

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Abstract  

A radioanalytical procedure for the determination of the chemical forms of35S in reactor irradiated crystals AlCl3, FeCl3 and AlCl3−FeCl3 is described. The method includes:35S extraction with trichloroethylene, precipitation of35S2− as iron sulfide and of (35SO 4 2− +35SO 3 2− ) as Ba-salts. All fractions are converted to, and measured as, BaSO4.

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Abstract  

The influence of Al on the absorption of various elements by a carrot (U.S. harumakigosun) was investigated using a multitracer technique. An uptake experiment was conducted within the range of 0.0–2.0 ppm AlCl3 in culture solution. By the addition of AlCl3, uptake of elements such as Be, V, Zn and rare earth elements (REE) into roots was increased. For Be and V an approximately three-fold increase was observed. The degree of uptake enhancement of nonessential elements by AlCl3 was generally very high, whereas some of the essential or beneficial elements exhibited a decrease in uptake with the increase of AlCl3 concentration. This suggests that the uptake of nonessential elements might be increased through transporters with decreased selectivity due to Al. From the viewpoint of the acid rain problem, it is suggested that one of the detrimental effects of Al on plants is the imbalanced elemental absorption.

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Abstract  

In the present work an attempt was made to obtain mineral–carbon sorbents by thermal decompositon. The mineral matrix for the sorbents (aluminium hydroxide) was based on petrochemical waste stream containing considerable amounts of aluminium chloride. Reference tests were carried out with a model solution prepared with the use of analytical grade AlCl3. Atactic polypropylene and hydrocarbon mixtures obtained in the flotation of petrochemical waste waters were used as carbon-containing raw materials. The aim of this work was to determine the adsorption and structural characteristics of the complex sorbents and to check the possibility of evaluation of their hydrophobic-hydrophilic properties.

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Abstract  

Phase transition and thermal decomposition of hexadimethylsulfoxidealuminium chloride were studied by differential scanning calorimetry (DSC), thermogravimetry (TG) and simultaneous differential thermal analysis (SDTA). The gaseous products of the decomposition were on-line identified by a quadrupole mass spectrometer (QMS). In the temperature range of 95–300 K, [Al(DMSO)6]Cl3 indicates one phase transition at T c h=244.96 K (on heating) and at T c c=220.87 K (on cooling). Large thermal hysteresis of the phase transition (∼24 K) indicates its first order character. Large value of transition entropy (ΔS≈40 J mol−1 K−1) suggests its configurational character. Thermal decomposition of the title compound proceeds in four main stages. In the first stage, which starts just above ca. 300 K, the compound loses two DMSO molecules per one formula unit and undergoes into [Al(DMSO)4]Cl3. In the second stage, the next three DMSO ligands are released and simultaneously decomposed. The third stage, which continues up to ca. 552 K, is connected with a loss of the last DMSO ligand and the formation of AlCl3. In the fourth stage AlCl3 reacts with carbon monoxide that originates from the decomposition of DMSO, and first aluminium oxychloride and next solid Al2O3 plus carbon are created.

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To assess the alternative responses to aluminum toxicity, maize (Zea mays L. cv Karadeniz yıldızı) roots were exposed to different concentrations of AlCl3 (150, 300 and 450 μM). Aluminum reduced the root elongation by 39.6% in 150 μM, 44.1% in 300 μM, 50.1% in 450 μM AlCl3 after 96 h period. To correlate the root elongation with the alternative stress responses including aluminum accumulation, lipid peroxidation, mitotic abnormalities, reduction of starch content, intracellular Ca2+ accumulation, callose formation, lignin deposition and peroxidase activity, cytochemical and biochemical tests were performed. The results indicated that aluminum accumulation and lipid peroxidation were observed more densely on the root cap and the outer cortex cells. In addition to morphological deformations, cytochemical analysis displayed cellular deformations. Furthermore, mitotic abnormalities were observed such as c-mitosis, micronuclei, bi- and trinucleated cells in aluminum treated root tips. Aluminum treatment induced starch reduction, callose formation, lignin accumulation and intracellular Ca2+ increase. Moreover, the peroxidase activity increased significantly by 3, 4.4 and 7.7 times higher than in that of control after 96 h, respectively. In conclusion, aluminum is significantly stressful in maize culminating in morphological and cellular alterations.

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Abstract  

The paper describes the synthesis of low molecular mass poly(allyl chloride) (PAC) (M n= 856-3834 g mol-1) using Lewis acid (ALCL3, FeCL3, TiCL4) and al powder. Branching in PAC was indicated on the basis of elemental analysis and 1H-NMR spectroscopy. azidation of pac could be carried out at 100°C by using NaN3 and DMSO as solvent. Curing of poly(allyl azide) (PAA) by cyclic dipolar addition reaction with EGDMA (ethylene glycol dimethacrylate, 5-45 phr) was investigated by differential scanning calorimetry and structure of cured polymer was confirmed by FTIR. A two-step mass loss was exhibited by uncured and cured PAA in nitrogen atmosphere. A mass loss of 20-28% (155-274°C) and 50-61% (330-550°C) was observed.

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Acta Alimentaria
Authors:
E. Tománková
,
J. Balík
,
I. Soural
,
P. Bednář
, and
B. Papoušková

This study presents findings from comparing the properties of anthocyanin pigments: i. malvidin-3-glucoside (Mal-3-G), the most significant anthocyanin present in young red wine; ii. Vitisin A (5-carboxypyranomalvidin-3-glucoside), a major product from a reaction induced in red wine between Mal-3-G and pyruvic acid during its ageing. These pigments were determined and compared to the absorption spectrum in 200–770 nm at various pH values, such results including the ability of cation Al3+ to change the values of absorbance. Changes in the colour parameters L* a* b* were determined in the CIELAB colour space of Mal-3-G and Vitisin A in relation to pH and the addition of AlCl3. Both coloured compounds were investigated for their resistance to discoloration by sulphur dioxide. Total antioxidant activity was evaluated by two methods (FRAP, DPPH), and the values were compared to other phenols.

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