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A green, scalable, and sustainable approach to prepare aqueous fullerene dispersions (AFD) C 60 , C 70 , endohedral metallofullerene Gd@C 82 , and their derivatives C 60 Cl 6 , C 70 Cl 10 , and supramolecular and ester-like derivatives, 10 fullerene species total, is proposed. For the first time, an immersed ultrasonic probe was used to preparing dispersions for pristine fullerenes without addends. Both ultrasound-assisted solvent-exchange and direct sonication techniques for AFD preparation using an immersed probe were tested. The average time for AFD preparation decreases 10-15 times compared to an ultrasound-bath-assisted technique, while final fullerene concentrations in AFDs remained at tens of ppm (up to 80 ppm). The aqueous dispersions showed long-term stability, a negatively charged surface with a zeta potential up to -32 mV with an average nanocluster diameter of no more than 180 nm. The total anionic and cationic compositions of samples were found by inductively coupled plasma atomic emission spectroscopy and chromatographic techniques. The highlights and challenges of using an ultrasound probe for AFD production are discussed., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

We show that electron transfer from the perchlorotriphenylmethide anion (PTM(-)) to Y@C82(C2v) is an instantaneous process, suggesting potential applications for using PTM(-) to perform redox titrations of numerous endohedral metallofullerenes. The first representative of a Y@C82-based salt containing the complex cation was prepared by treating Y@C82(C2v) with the [K(+)([18]crown-6)]PTM(-) salt. The synthesis developed involves the use of the [K(+)([18]crown-6)]PTM(-) salt as a provider of both a complex cation and an electron-donating anion that is able to reduce Y@C82 C2v). For the first time, the molar absorption coefficients for neutral and anionic forms of the pure isomer of Y@C82(C2v) were determined in organic solvents with significantly different polarities., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The EPR spectrum of the Y@C(82) molecules isolated in solid argon matrix was recorded for the first time at a temperature of 5 K. The isotropic hyperfine coupling constant (hfcc) A(iso) = 0.12 +/- 0.02 mT on the nucleus (89)Y as derived from the EPR spectrum is found in more than two times greater than that obtained in previous EPR measurements in liquid solutions. Comparison of the measured hfcc on a metal atom with that predicted by density-functional theory calculations (PBE/L22) indicate that relativistic method provides good agreement between experiment in solid argon and theory. Analysis of the DFT calculated dipole-dipole hf-interaction tensor and electron spin distribution in the endometallofullerenes with encaged group 3 metal atoms Sc, Y and La has been performed. It shows that spin density on the scandium atom represents the Sc d(yz) orbital lying in the symmetry plane of the C(2v) fullerene isomer and interacting with two carbon atoms located in the para-position on the fullerene hexagon. In contrast, the configuration of electron spin density on the heavier atoms, Y and La, is associated with the hybridized orbital formed by interaction of the metal d(yz) and p(y) electronic orbitals.

Adding 1% of the metallic elements cerium, lanthanum, and yttrium to graphite rod electrodes resulted in different amounts of the hollow higher fullerenes (HHFs) C76-D2(1), C78-C2v(2), and C78-C2v(3) in carbon-arc fullerene-containing soots. The reaction of trifluoroiodomethane with these and other soluble HHFs at 520-550 degrees C produced 21 new C76,78,84,90(CF3)n derivatives (n = 6, 8, 10, 12, 14). The reaction with C76-D2(1) produced an abundant isomer of C2-(C76-D2(1))(CF3)10 plus smaller amounts of an isomer of C1-(C76-D2(1))(CF3)6, two isomers of C1-(C76-D2(1))(CF3)8, four isomers of C1-(C76-D2(1))(CF3)10, and one isomer of C2-(C76-D2(1))(CF3)12. The reaction with a mixture of C78-D3(1), C78-C2v(2), and C78-C2v(3) produced the previously reported isomer C1-(C78-C2v(3))(CF3)12 (characterized by X-ray crystallography in this work) and the following new compounds: C2-(C78-C2v(3))(CF3)8; C2-(C78-D3(1))(CF3)10 and C(s)-(C78-C2v(2))(CF3)10 (both characterized by X-ray crystallography in this work); C2-(C78-C2v(2))(CF3)10; and C1-C78(CF3)14 (cage isomer unknown). The reaction of a mixture of soluble higher fullerenes including C84 and C90 produced the new compounds C1-C84(CF3)10 (cage isomer unknown), C1-(C84-C2(11))(CF3)12 (X-ray structure reported recently), D2-(C84-D2(22))(CF3)12, C2-(C84-D2(22))(CF3)12, C1-C84(CF3)14 (cage isomer unknown), C1-(C90-C1(32))(CF3)12, and another isomer of C1-C90(CF3)12 (cage isomer unknown). All compounds were studied by mass spectrometry, (19)F NMR spectroscopy, and DFT calculations. An analysis of the addition patterns of these compounds and three other HHF(X) n compounds with bulky X groups has led to the discovery of the following addition-pattern principle for HHFs: In general, the most pyramidal cage C(sp(2)) atoms in the parent HHF, which form the most electron-rich and therefore the most reactive cage C-C bonds as far as 1,2-additions are concerned, are not the cage C atoms to which bulky substituents are added. Instead, ribbons of edge-sharing p-C6(X)2 hexagons, with X groups on less pyramidal cage C atoms, are formed, and the otherwise "most reactive" fullerene double bonds remain intact.

Peculiarities of the protective effect of ciprofloxacin and lomefloxacin were studied and the optimal regimens of their use were determined in multifactor experiments on albino mice infected with finally dispersed aerosol of the virulent strain of the European subspecies of Francisella tularensis. As for protective effect, the fluoroquinolones provided high percentage of the animal survival. The optimal course of the treatment was at least 7 days. The interval of 0 to 48 hours between the infection and the start of the treatment had no statistically significant effect on chemotherapeutic efficacy of fluoroquinolones.

The protective effects of doxycycline, rifampicin and sisomicin were compared in a multifactor experiment with animal infection induced by finally dispersed aerosol of a virulent strain of the European variant of the tularemia causative agent and the optimal regimens for the antibiotic use were determined. By the values of the protective effect rifampicin and sisomicin were shown to provide a high percentage of the animal survival: more than 80 and up to 50-70 per cent of the animals survived when the aerosol infective doses were 100 and 10,000 LD50, respectively. A characteristic feature of doxycycline was its activity only in the infection induced by low doses of the biological agent. The optimal course of the antibiotic therapy in inhalation tularemia was 6 to 8 days. The interval of 1 to 3 days between the infection and the therapy start had no significant effect on the protective efficacies of the antibiotics.

The ability of Ukrain, a cytostatic and immunomodulating semisynthetic compound of thiophosphate-modified alkaloids of Chelidonium majus L., to modify the effects of irradiation was studied in CBA/J mice using the dosage of the drug from 0.2 to 10 mg/kg. Ukrain was found to increase the survival rate of mice by 50-60 percent at irradiation doses from 6.00 to 6.75 Gy with no effect at the dose of 7.5 Gy. Varying the dosage of the drug did not influence the outcome of irradiation under experimental conditions employed. Maximal increase in the survival rate of the mice was noted when the drug was administered within the interval from 6 h before to 3 h after irradiation. It is noteworthy that under no circumstances did the administration of Ukrain result in a decrease in the survival rate of irradiated animals. The main outcome of the present study is the finding that Ukrain is capable of modifying the effects of irradiation when applied in both prophylactic and curative regimens. The effects of Ukrain are evident at doses from 0.2 to 10 mg/kg over the entire time-range studied and under doses of irradiation not exceeding LD 85/30. The drug was also found to be able to modify the effects of prolonged irradiation.