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The influence of additives of alkali, alkaline-earth, and several transition metal cations, protonated amines, and quaternary ammonium on the state of the tetrahedral cobalt(II) thiocyanate complex is studied in an aqueous solution of the nonionogenic surfactant Triton X-100. It is shown that alkali and alkaline-earth metal cations and compounds containing protonated primary amino groups favor the formation of additional amounts of the micellar-bonded [Co(NCS)4]2– complex anion. This fact is explained by the interaction of these cations with the oxyethylene chains of the nonionogenic surfactant as was observed in the crown ether coordination. This provides the formation and transfer into micelles of additional amounts of their associates with [Co(NCS)4]2–. The Mn2+, Ni2+, and Cd2+ cations decompose cobalt tetrathiocyanate due to the formation of their own complexes with the ligand. This effect is not observed in the case of the quaternary ammonium compounds, which is explained by their incapability of coordinating the oxyethylene chains of the nonionogenic surfactant. 相似文献
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The decoloration yield of oxazine 720 in ethanolic solution was studied as a function of dose rate and concentration of the dye. Linear response for G values to a dose of 1.68 KGy was observed for various dye concentrations. The effect of various organic substances in the radiolysis of the dye was studied and the results were interpreted in terms of scavenging reactions. 相似文献
4.
Rabadanov K. Sh. Gafurov M. M. Kubataev Z. Yu. Amirov A. M. Akhmedov M. A. Shabanov N. S. Ataev M. B. 《Russian Journal of Electrochemistry》2019,55(6):573-578
Russian Journal of Electrochemistry - Composite solid electrolytes are synthesized on the basis of the eutectic nitrate mixture of 0.42LiNO3–0.58KNO3 doped by aluminum oxide nanosized powder.... 相似文献
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The HNO3‐mediated CH2 extrusion reactions of phenylacetic acid lead to one pot synthesis of unexpected commercially important product 4‐nitrobenzoic acid through the formation of 4‐nitrophenylacetic acid and 2‐nitrophenylacetic acid. 相似文献
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R. Kh. Amirov N. A. Vorona A. V. Gavrikov G. D. Liziakin V. P. Polistchook I. S. Samoylov V. P. Smirnov R. A. Usmanov I. M. Yartsev 《Physics of Atomic Nuclei》2015,78(14):1631-1634
One of the key problems in the development of plasma separation technology is designing a plasma source which uses condensed spent nuclear fuel (SNF) or nuclear wastes as a raw material. This paper covers the experimental study of the evaporation and ionization of model materials (gadolinium, niobium oxide, and titanium oxide). For these purposes, a vacuum arc with a heated cathode on the studied material was initiated and its parameters in different regimes were studied. During the experiment, the cathode temperature, arc current, arc voltage, and plasma radiation spectra were measured, and also probe measurements were carried out. It was found that the increase in the cathode heating power leads to the decrease in the arc voltage (to 3 V). This fact makes it possible to reduce the electron energy and achieve singly ionized plasma with a high degree of ionization to fulfill one of the requirements for plasma separation of SNF. This finding is supported by the analysis of the plasma radiation spectrum and the results of the probe diagnostics. 相似文献
9.
Shamsa Munir Afzal Shah Abdur Rauf Amin Badshah Hidayat Hussain Zia-ur-Rehman Zahoor Ahmad 《Comptes Rendus Chimie》2013,16(12):1140-1146
The present work reports the redox mechanism of 5-hydroxynaphthalene-1,4-dione (HND), commonly known as juglone, in buffered aqueous media having 50% of ethanol. HND followed different mechanistic routes depending upon the pH of the media and more than one pKa were evaluated from the changes in the slope of the Ep vs. pH plot. The change of pH from acidic to neutral conditions was found to switch the mechanism from CEC to EE mechanism. Pulse techniques were utilized to determine the number of electrons involved in the oxidation and/or the reduction step and to ensure the nature of the redox process. Based upon the obtained results, an electrode reaction mechanism was proposed. Computational studies of HND supported the experimental results. UV-Visible spectroscopy was also employed for the detailed characterization of the compound in a wide range of pH and for the determination of its pKa. 相似文献
10.
Kolb NR Rauf AW Igarashi R Hornidge DL Pywell RE Warkentin BJ Korkmaz E Feldman G O'Rielly GV 《Physical review letters》2000,85(7):1388-1391
Cross sections for quasifree Compton scattering from the deuteron were measured for incident energies of E(gamma) = 236-260 MeV at the laboratory angle straight theta(gamma(')) = -135 degrees. The recoil nucleons were detected in a liquid-scintillator array situated at straight theta(N) = 20 degrees. The measured differential cross sections were used, with the calculations of Levchuk et al., to determine the polarizabilities of the bound nucleons. For the bound proton, the extracted values were consistent with the accepted value for the free proton. Combining our results for the bound neutron with those from Rose et al., we obtain 1-sigma constraints of alpha;(n) = 7.6-14.0 and beta;(n) = 1.2-7.6. 相似文献