[en] In this article the result with malonings reagents. The structure of obtained compounds are proved by physic-chemical methods

[en] Complete text of publication follows. Mechanistic studies were made on ^·OH radical and hydrated electron reaction with Sulfanilic Acid Azochromotrop (SPADNS) as model azo dye. SPADNS contains 4,5-dihydroxynaphtalene 2,7-disulfonic acid part and 4-sulfophenylazo group. To establish the details of the reaction mechanism the reactions of two simpler molecules without 4-sulfophenylazo part were also studied: one of them contained one (in position 4, II), the other two (in positions 4 and 5, III) -OH groups. ^·OH radicals react with these molecules with radical addition to the naphthalene 2,7-disulfonic acid part. The adduct cyclohexadienyl type radical may decay in radical-radical reactions, or undergoes a (pH dependent) water elimination to naphthoxy radical, radical decay takes place on the ms timescale. ^·OH radical addition on the azo bond in dyes has low importance. Degradation efficiencies are 0.6-0.8. The hydrated electron in the case of the two simpler molecules reacts with the rings, while in the case of dye with the azo bond. Electron scavenging is followed by protonation, this reaction in the case of II and III yields cyclohexadienyl, while with the dye hydrazo radical. The efficiency of degradation with II and III is 0.2-0.6, while for the dye it is close to 1.

No abstract available

[en] The investigation was devoted to thione-thiols tautomerism equilibrium analysis at five-ring heterocycles by the UV-spectroscopy. It was shown that tautomeric equilibrium depend on different factors, such as solvents and reagents

[en] Perfluorooctanesulfonate (PFOS) and perfluorooctanesulfonic acid (PFOA) have been identified as contaminants of emerging concern in Australia. They are known to be persistent, bioaccumulative and potentially toxic, and have been found to be present at concentrations of potential concern at a number of sites, particularly where there has been historical use of fire fighting foams containing these contaminants and their precursors. Industry and public awareness of the presence of PFOS and PFOA particularly has been growing rapidly, with understanding of the effects and screening criteria being published both in Australia and internationally on a frequent basis. CRC CARE has been undertaking a project to provide guidance on the assessment, management and remediation of PFOS and PFOA, and has formed working groups comprising representatives of regulatory agencies, industry and research organisations. A draft and interim guide was published in early 2017, and this has been revised to include updated advice from the Health agencies and environmental regulatory agencies. It is intended that this guide will assist practitioners, regulators and site owners to effectively assess, manage and remediate soil and groundwater contaminated with PFOS and PFOA using a risk-based approach. It is expected that the guidance will assist remediation decision-making, and potentially reduce the cost of managing contaminated soil and groundwater. In particular, the guide includes: The extent and magnitude of PFOS/PFOA contamination in Australia; Information on toxicity, bioaccumulation and persistence; Information on the impacts on beneficial uses, with a focus on soil, groundwater and receiving waters; Ecological and human health screening levels that have been published by Australian agencies, and have been developed by CRC CARE, including information on the rationale for development, assumptions and uncertainties; Important considerations in developing conceptual site models for PFOS/PFOA, and the technologies and practicable management and remediation strategies that can be used to reduce the risks to an acceptable level. (author)

[en] Ultraviolet light (lambda > 295 nm) induced binding of sulfanilamide to cellular macromolecules has been examined. It was found that the drug bound irreversibly to native DNA, and complexes containing one drug molecule per 80 nucleotides were obtained after 60 min of irradiation under anaerobic conditions. Oxygen reduced this binding significantly. More drug was bound to RNA and heat denatured DNA under identical conditions. The binding of sulfanilamide to DNA was found to induce nicking of circular closed plasmid DNA and cross-linking of calf thymus DNA. Oxygen significantly decreased nicking and cross-linking of DNA. Irradiation of sulfanilamide and human serum albumin resulted in covalent binding of the drug to the protein and a concomitant increase in protein crosslinking. While oxygen decreased covalent binding, crosslinking increased under aerobic conditions. These reactions may be important in the photosensitization caused by sulfanilamide. (author)

[en] To avert excessive sulfuric acid exhaustion in the classical leaching procedure and to avoid leaching of other undesirable impurities, proper alkaline leaching has been achieved for dolostone of Gabal Allouga, South western Sinai, Egypt. The relevant factors for alkaline leaching of a technological sample assaying 1.2% Cu and 0.15% U were examined using a mixture of Na₂CO₃/(NH₄)HCO₃ solution upon two samples namely; roasted sample at 540 ° C and raw materials un-roasted. The leaching kinetic results showed that the leaching procedure of uranium and copper from dolostoneis controlled by shrinking core kinetic model 1-2/3(X)−(1−X)^2/3=k_dt

[en] The authors demonstrate a single-step histidine assay that is based on the use of silver nanoparticles modified with sulfanilic acid (SAA-AgNPs). The presence of histidine leads to a visually detectable gradual color change from bright yellow via orange to purple. The effect is assumed to be mainly due to strong π-π stacking, electrostatic interaction, and hydrogen bonding between SAA and histidine. The assay has a 52.7 nM detection limit and works in the 0 to 3.5 μM concentration range. It is selective over other compounds when using appropriate masking agents. The method has been successfully applied to the colorimetric determination of histidine in (spiked) serum samples. Recoveries ranged between 97 % and 107 %, and relative standard deviations are <0.92 % (for n = 3). The method was also applied to detect polyhistidine-tagged cysteine (His-His-His-His-His-His-Cys) which can be quantified in concentrations down to 5.57 nM. This finding links the method to His-tag technology. (author)

[en] The determination of base compositions of ribonucleic acids is an important step in sequence analysis. A simple, sensitive procedure for chemically labelling RNA and its derivates which uses p-hydrazinobenzene-[³⁵S]sulphonic acid as the radioactive labelling reagent was described previously, and makes use of [³⁵S]sulphanilic acid. Now a routine labelling method for determining base compositions of RNA and ribooligonucleotides is presented, using the same procedure. The procedure is simple and very sensitive requiring only 0.5 μg of the polymer for at least a triplicate determination

No abstract available