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In this work, two thin hybrid composites based on organic-like fullerenes (bucky balls C60) and inorganic compounds of lithium cobalt oxide (LiCoO2) were prepared. The composites were synthesized by a combined method of ion sputtering and evaporation. The prepared samples were sandwiched between 2 gold electrodes and subjected to charging at an applied small voltage. After each charging process, the samples were analyzed using two appropriate methods—the surface morphology was monitored using AFM (Atomic Force Microscopy), and lithium depth concentration profiles were measured using NDP (Neutron Depth Profiling). The results of the measurements showed that both types of composite experienced significant changes both in the surface morphology and especially in the depth distribution of lithium. The test confirmed the expectation that the unusual hybrid combination of organic and inorganic phases is electrochemically active and exhibits characteristics of Li battery behavior. [ABSTRACT FROM AUTHOR]

A comparative study of the temperature stability of a full-formula motor oil, Mobil Ultra SAE 10W-40, doped with two carbon nanoadditives (nanotubes and fullerenes) is presented. The optimum concentrations of the compared nanoadditives in terms of friction coefficients, as well as the optimum concentrations in terms of the amount of heat released during friction, have been preliminarily established. It was found that doping the studied oil with fullerene increases the critical temperature by 10–15°C, and alloying this oil with carbon nanotubes increases the critical temperature by 20–25°C. [ABSTRACT FROM AUTHOR]

Fullerene C60 exhibits potent antioxidant anti-inflammatory activities as well as anticancer activities. In this study using 60 Wistar albino female rats (n = 60, 8 weeks old), they rats were divided into 4 groups, including 15 rats each. The groups were arranged as follows: (i) Control Group: Group fed with standard diet; (ii) C60 Group: C60 (1.7 mg/kg bw, oral gavage); (iii) DMBA (7,12-dimethylbenz[a]anthracene) Group: DMBA (45 mg/kg bw, oral gavage); (iv) C60 and DMBA Group: C60 (1.7 mg/kg bw, oral gavage) and DMBA (45 mg/kg bw, oral gavage) group. DMBA increased the malondialdehyde levels in muscle tissue, while decreasing GSH and CAT levels; however, treatment with fullerene C60 reversed these effects. In addition, the oral administration of fullerene C60 increased caspase-3 and Nrf-2 protein expression and significantly decreased Bcl-2, NF-κB, TNF-α, COX-2 and p38α (MAPK) protein expression in C60 + DMBA compared to the DMBA group. Moreover, histopathological imaging revealed that the oral administration of fullerene C60 decreases inflammatory cells, edema formation, and hydropic degeneration in the muscles. Taken together, the results of the present study indicated that fullerene C60 nanoparticle provides effective protection by preventing muscle tissue damage. [ABSTRACT FROM AUTHOR]

In this article, a comprehensive methodology has been developed to study the lubricity of oils with solid micro/nanoadditives, including mathematical models that allow estimating the temperature during shear and variable speed in the layer. The dynamic temperature gradient across the thickness, the variable thickness, the friction moment, and the temperature are calculated. [ABSTRACT FROM AUTHOR]

Results are given for a kinetic study of the synthesis of a new fullerene derivative containing a diterpene fragment obtained using HPLC and subsequent mathematical modelling. Kinetic and activation parameters were found for the cyclopropanation of fullerene using the Bingel procedure and a reaction mechanism was proposed. The optimal synthesis conditions were found to entail a slight excess of a chlorine‑containing cyclopropanation agent and carrying out the reaction at room temperature. [ABSTRACT FROM AUTHOR]

A method has been developed for the synthesis of new fused 1,4-benzoxazine monoadducts of fullerene C60 by the reaction with 2-aminophenols (2-aminophenol, 2-amino-4-methylphenol, 3-amino-[1,1′-bi-phenyl]-4-ol) in the presence of LiOH and Pb(OAc)4. A probable reaction mechanism has been proposed. [ABSTRACT FROM AUTHOR]

Fullerene C60 is known to have particularly strong antioxidant ability to protect against oxidative stress-induced dysfunctions and tissue damage. In this study, the preventive effects of C60 were investigated in rats that caused eye tissue damage with 7,12-dimethylbenz[a]anthracene (DMBA). 60 Wistar albino female rats were used in the study. Groups: (i) Control Group: Group fed with standard diet; (ii) C60 Group: Fullerene C60 (1.7 mg/kg bw, oral gavage) given group; (iii) DMBA Group: The group given DMBA (45 mg/kg bw, oral gavage); (iv) C60 + DMBA Group: Fulleren C60 (1.7 mg/kg bw, oral gavage) and DMBA (45 mg/kg bw, oral gavage) group. Each group included 15 female rats and the study continued for 16 weeks. The protein levels were determined by western blotting and the biochemistry parameters were determined with spectrophotometric assays in rat eye tissue homogenates. Compared to the DMBA given group in the eye tissue, a decrease was observed in MDA levels and IL-1α and COX-2 protein expression levels, and an increase in GSH level, CAT activity and caspase-3, HO-1, p53 and Beclin-1 expression levels in the C60 given groups. Our results show that fullerene C60 protects eye tissue from oxidative damage and reduces inflammation via trigging HO-1 expression. [ABSTRACT FROM AUTHOR]

This article compares machine learning methods and a numerical method of determination of the doped lubricating layer with experimental data. Based on the sweep method, the one-dimensional Fourier heat equation with boundary and initial conditions is solved. As a result of comparing numerical and predictive data with experiments, it can be concluded that machine learning models are better at predicting results compared to numerical data. [ABSTRACT FROM AUTHOR]

The 13C NMR chemical shifts of fullerene C60 exo-derivatives were calculated using quantum chemical hybrid functionals combined with Pople, Dunning correlation-consistent, and def2-TZVP split valence basis sets taking into account the solvent effect (polarizable continuum model). A relationship between theoretical and experimental 13C NMR chemical shifts (CSs) is assessed quantitatively to select a functional/basis set combination. It is found that the CAM-B3LYP/6-31G and M06L/6-31G combinations have the best convergence with experimental data in modeling the 13С NMR CSs of sp3 fullerene carbon atoms in С60 derivatives, whereas X3LYP/6-31G and CAM-B3LYP/6-31G(d) in modeling the 13С NMR CSs of their sp2 fullerene carbon atoms. [ABSTRACT FROM AUTHOR]

The permeability of a C60 fullerite in a simple cubic phase for natural gas components is investigated. The classical molecular dynamics methods and the Monte Carlo method are used to study the physical effects appearing in the case where the particles pass through a thin layer of a crystalline fullerite. A discrete model of atom-atom interactions is used to take into account the mutual influence of the elements of the system (fullerenes and penetrating particles). The influence of the incoming particle velocities on the permeability is shown, and a characteristic factor affecting the permeability of the crystalline system is determined. [ABSTRACT FROM AUTHOR]

In this study, the impacts of different non-polar organic solvents on nonlinear optical response of fullerene C60 have been investigated. Linear properties of C60 fullerene have been synthesized with two different concentrations of 3% and 6% wt in non-polar organic solvents including toluene and xylene and then characterized using UV–VIS spectroscopy. The band gap of C60 fullerene in non-polar solvents including toluene and xylene has been found to be 2.9 eV, 2.96 eV and 2.86 eV, 2.87 eV for 3% wt and 6% concentrations, respectively. Raman spectrum for solid C60 with 272 cm−1, 430 cm−1, 496 cm−1, 704 cm−1, 772 cm−1, 1422 cm−1, 1467 cm−1, and 1573 cm−1 shifting and scanning transmission electron microscopy (STEM) were recorded for C60 in xylene with the dimension range 100–500 nm. Nonlinear optical responses of C60 fullerene in non-polar organic solvents have also been investigated using fs laser z-scan technique. Real and imaginary parts of third-order nonlinear susceptibility have been investigated and nonlinear absorption coefficient (β), nonlinear refractive index (n 2) and third-order nonlinear optical susceptibility ( χ (3) ) values for the samples have been calculated to be on the orders of 10–10 cm/W, 10–16 cm2/W and 10–13 esu, respectively. Obtained numerical results of these values can be concluded to be promising case for the optical limiters as compatibility with the literature. [ABSTRACT FROM AUTHOR]

The present study aimed to investigate the therapeutic effect of fullerene C60 nanoparticle against heart tissue damage caused by 7,12-dimethylbenz [a] anthracene (DMBA) in female rats. Female Wistar albino rats, 8 weeks old (n = 60) weighing around (150 ± 10 g) were used for the study. These rats were divided into 4 groups and each group included 15 rats. Groups: (i) Control Group: Fed with standard diet; (ii) C60 Group: C60 (1.7 mg/kg bw, oral gavage); (iii) DMBA Group: DMBA (45 mg/kg bw, oral gavage); (iv) C60 and DMBA Group: C60 (1.7 mg/kg bw, oral gavage) and DMBA (45 mg/kg bw, oral gavage) group. Malondialdehyde (MDA) analysis, catalase activity (CAT), and glutathione (GSH) in heart tissue were determined by spectrophotometer. In addition, heart tissue DNA damage was investigated. Caspase-3, p53, HO-1, COX-2, and TNF-α protein expression levels in heart tissue were determined by western blotting. As a result, Caspase-3, p53, HO-1 protein expression, GSH levels and CAT activity increased, COX-2, TNF-α protein expression, and MDA levels were significantly decreased in the C60 + DMBA group compared to the DMBA group. Therefore, the fullerene C60 nanoparticle may be a promising and effective therapy for the treatment of heart diseases associated with inflammation. [ABSTRACT FROM AUTHOR]

Using the density-functional theory (DFT) method, potential energy surfaces are calculated for M + C60 (M = He, Ne, Ar, HF) systems, where molecules M are encapsulated inside the fullerene C60 molecule. The frequencies of three-dimensional vibrations in these systems are calculated (259, 175, 340, and 109 cm–1, respectively). Vibrational rotation with moment increases these energies by value ( , 132, 170, and 96 cm–1, respectively). The Schrödinger equation is solved for the HF molecule motion inside the C60 cage. The Coriolis vibrational—rotational interaction is detected, where two types of rotational moments ( and l, where the former is the motion inside C60 and the latter is the HF rotation) are coupled and produce a total rotational moment, and these two motions are mixed. [ABSTRACT FROM AUTHOR]

Morpholine–fullerene C60 monoadducts were synthesized for the first time by reaction of C60 with biogenic amines (noradrenaline and adrenaline) under ultrasonic irradiation in toluene/DMF at room temperature on exposure to air. The key intermediate in the synthesis of the C60–adrenaline cycloadduct, C60 radical anion generated by single-electron transfer from the adrenaline molecule to C60, was detected by ESR (C60‒·, g = 2.0000, ΔH1/2 = 3.2 G). [ABSTRACT FROM AUTHOR]

The HIV (human immunodeficiency virus) attacks the immune system that, if not treated, causes AIDS. It also penetrates the central nervous system and causes HIV-related neurological disorders (HAND). In this study, fullerene C60 is proposed as a nanocarrier for Amprenavir (Amp), an anti-HIV drug. Also, some physicochemical properties of [Amp + C60] nanocomplex and its components have been theoretically investigated. The dipole moment of two components in the discussed complex (7.292 D) predicts that it will be soluble in polar solvents like water. Therefore, the process of drug delivery through the polar media will be feasible. Investigation of the formation energy and reduced density gradient of the discussed complex confirm that its components interact via weak interactions like Van der Waals forces. Thus, the release of the drug into the target tissue can be easily practical. It assumes no damage to Amp will occur. Fullerene, with unique properties as a highly delocalized conjugated π system, has shown high antioxidant capacity. The density of states and charge decomposition analysis revealed significant contribution of fullerene in the discussed complex orbitals. Amp will be preserved against adverse reactions during drug delivery due to the frontier complex orbitals that they are located on the fullerene part. Anti-HIV drugs like Amp are not able to cross the blood–brain barrier (BBB) and prevent HAND. Fullerene C60 may allow Amp to be transported across the BBB due to its small size and hydrophobicity. Examination of the Mulliken charge changes of the involved atoms, electron localization function , natural bond orbital , and electrostatic potential analyses indicate that the application of fullerene will improve the interaction of Amp with the virus protease. The photo-induced electron transfer studies have demonstrated that some electron transfer processes occurred in the discussed complex from Amp to fullerene C60 part. This feature can be utilized for monitoring and detecting the drug during the drug delivery process. [ABSTRACT FROM AUTHOR]

The influence of the introduction of 10 wt % fullerene soot containing 8.5% fullerene C60 into Litol-24 grease on the sliding friction features in the R6M5 steel–45 steel pair in the load range 0–1400 N is studied. The introduction of the additive causes a number of changes in the basic laws of sliding friction and leads to a decrease in the friction force by ~2.5 times and the coefficient of friction by ~3 times. The most pronounced improvement in the tribotechnical characteristics is detected in the load range 600–1335 N. For both the lubricant without additives and the lubricant with the addition of fullerene soot, the load dependence of the friction force has a piecewise linear form, a simple linear version of the Amonton–Coulomb law is obeyed in each of the sections, and a generalized version of the Amonton–Coulomb law is obeyed in both cases with allowance for changes in the friction interaction conditions. [ABSTRACT FROM AUTHOR]

An experimental study has been made of the influence of the concentration of a solvent and a solute on the clusterization of fullerene C60 molecules in a C60/xylol/hexane solution by refractometry methods. By the methods of dynamic light scattering and transmission electron microscopy, it has been established that when a nonequilibrium method of preparation of a fullerene C60 solution in binary mixtures (xylol + hexane) is employed negatively charged clusters of diameters ~60–70 nm are formed in the solution. It has been established that the high aggregative stability of the solution of fullerene with a concentration of C60 of ~0.036 g/L is determined by the relatively high values of the electrokinetic ζ potential of nanoclusters (ζ = –26.6–28.2 mV). [ABSTRACT FROM AUTHOR]

Due to its unique hybridization, derivatization ease, and significant properties, fullerene C60 has been extensively utilized as a drug delivery carrier and antiviral agent. Abacavir is an essential medicine used for the prevention and treatment of acquired immunodeficiency syndrome (AIDS). In the present study, the [C60 + Abacavir] nano-complex properties have been scrutinized in both ground and excited states applying density functional theory (DFT) and time-dependent density functional theory (TD-DFT). An investigation of the data by using the density of states, electron localization function, natural bond orbital, reduced density gradient, charge decomposition analysis, and the electrostatic potential map, revealed that the type of the intermolecular interaction between abacavir and C60 is Van der Waals force. This type of interaction would be useful in the release of abacavir into the target tissue. Also, the changes in the electron configuration before and after the complexation have been studied. The umpolung phenomenon index of the complex is equaled to 0.5 by calculating the partial accumulated Mulliken charges of the atoms involved. The complex dipole moment value of 1.07D proposes that the [C60 + Abacavir] complex may be soluble in polar solvents, such as physiological media, contrary to the pure fullerene. Therefore, it can transfer through blood. The ability of fullerene to cross, penetrate, and localize in hydrophobic domains makes it useful for drug delivery to lipid-rich regions. Besides, the complexation of abacavir with fullerene C60 would make abacavir more reactive in phosphorylation reaction for inhibiting HIV protease. Based on the results, the use of fullerene C60 nano-carrier can improve the efficacy of abacavir. Photo-electron transfer also has been investigated according to electron–hole and Marcus theories. The charge transfer process between two components may cause quenching fluorescence emission. Subsequently, tracing and detecting the nano-complex will be possible during the drug delivery. These electron transfer processes can bring about by applying external potentials. The results show that the H-atoms in the anisotropic field of fullerene have significantly changed in the chemical shifts. Therefore, fullerene C60 can be proposed as an organic chemical shift reagent in some NMR studies. [ABSTRACT FROM AUTHOR]

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The kinetic characteristics, mechanisms of activity, and relationship between the antioxidant activity and the molecular and supramolecular structure of fullerene C60 and some of its N-monosubstituted amino acid derivatives have been studied. The introduction of an amino acid substituent in the C60 fullerene molecule led to an increase in its antiradical activity in the free radical oxidation of a water-soluble target (fluorescein). The mechanism of the antioxidant activity of amino acid derivatives of fullerene is not associated with the hydrogen atom transfer, electron donation, or catalysis of peroxide decomposition. It was demonstrated that the structure of the amino acid substituent does not affect the antiradical properties, which are thus determined only by the effective total surface area of ​​the nanoparticles of the fullerene C60 derivatives and increase when their size decreases. This surface can be characterized as nanowalls on which the radical death occurs. A change in the concentration of the compounds in solution does not lead to a change in the relative antiradical activity and hence in the nanoparticle size. The results of this study are important for understanding the biological activity of this group of compounds. [ABSTRACT FROM AUTHOR]

We developed amperometric biosensors for the determination of diclofenac based on screen-printed platinum electrodes modified by carbon nanotubes in chitosan, fullerene C60 in Boltorn H20, gold nanoparticles in chitosan, and immobilized tyrosinase enzyme. Diclofenac is a reversible tyrosinase inhibitor, which enables its determination using appropriate biosensors modified by nanomaterials in the concentration range from 10 pM to 1 μM with cl = 5 pM. Kinetic studies of the reaction of the enzymatic conversion of phenol showed that, in the presence of diclofenac, noncompetitive inhibition is observed on a tyrosinase biosensor. We tested the procedures for the determination of diclofenac in cow's milk using the proposed biosensors. [ABSTRACT FROM AUTHOR]

A quantum chemical simulation of the sixfold addition of 2-cyano-iso-propyl radical to fullerene C60 and the formation of a number of isomeric adducts is carried out. The thermodynamic characteristics of the elementary acts and the pattern of the spin density delocalization in fullerene C60 adducts containing an odd number of addends are determined. It is shown that the addition of up to four 2-cyano-iso-propyl radicals to fullerene C60 leads to the attachment of radicals to the tops of the radilene of the fullerenyl part of the adducts. The addition of the fifth 2-cyano-iso-propyl radical proceeds to the atoms more distant from the previously attached addends in the tetrakisadduct. [ABSTRACT FROM AUTHOR]

Long-chain alka-2,3-dienoates were synthesized via the Wittig reaction from the corresponding fatty acids, and the subsequent triphenylphosphine-catalyzed [3+2]-cycloaddition to fullerene C60 afforded new lipophilic cyclopentafullerenes. [ABSTRACT FROM AUTHOR]

In recent years, the impact of ultrafine nanomaterials on the aquatic organisms and their ecosystems contributed much concern due to their abundance in environment. Several toxicity studies have reported that nanoparticles induced reproductive stress and resulted in reproductive impairment of fishes. The present study was aimed to investigate the stress-induced toxicity of C60 fullerene nanomaterial on various reproductive parameters of the freshwater fish, Anabas testudineus. Fish were exposed to two sublethal concentrations of fullerene C60, one-tenth (5 mg/L) and one-fifth (10 mg/L) of LC50–96 h, for 4, 7, 15, 30, and 60-day durations. At the end of exposure period, the activities of steroidogenic enzymes, 3β-, and 17β-hydroxysteroid dehydrogenase decreased in the testis and ovary thereby indicated that the nanomaterial affected gonadal steroidogenesis. The level of serum testosterone decreased significantly (p < 0.05) in male whereas the level of estradiol showed significant (p < 0.05) reduction in female fish with significant (p < 0.05) increase in the level of serum cortisol in both sexes in concentration- and time-dependent manner. The analysis of the levels of alkali-labile phosphates, plasma calcium, and total protein showed significant (p < 0.05) reduction in female fish without significant changes in male fish, and this could be due to the antiestrogenic action of fullerene C60 nanomaterial. The activity of aromatase enzyme decreased significantly (p < 0.05) in the ovary and brain of female fish, and the decline in the enzyme activity was prominent only in the brain tissue of male fish. The present results suggested that the stress-induced by fullerene C60 exposure provoked reproductive toxicity in the fish, Anabas testudineus. [ABSTRACT FROM AUTHOR]

The unique physico-chemical properties of fullerene C60 have aided in its application in various fields along with several ecological impacts as an emerging pollutant. So, there is a significant need to demonstrate the ecological risk and toxic impact of fullerene C60 in the freshwater ecosystem. The present study focused on the toxic impact of fullerene C60 on behavioral and hematological changes in the freshwater fish, Anabas testudineus. The acute toxicity of fullerene C60 in Anabas testudineus determined by Probit analysis was found to be 50 mg/L. For the analysis, the fish were exposed to two sublethal concentrations of 5 mg/L (one-tenth of LC50-96 h) and 10 mg/L (one-fifth of LC50-96 h) for short-term (24, 48, 72 and 96 h) and long-term (7, 15, 30 and 60 days) durations. Fullerene C60 exposure showed prominent changes in behavior of the fish that comprises changes in swimming activity, disruption of schooling behavior, air engulping and surfacing along with morphological alterations such as descaling, slight hemorrhage and mucous secretion on the body surface, which was correlated to significant (P < 0.05) decrease in the activity of acetylcholinesterase enzyme in brain tissue. Hematological changes includes significant (P < 0.05) reduction in the erythrocyte and leukocyte counts, hemoglobin concentration, percentage of the packed cell volume (hematocrit) and the levels of serum albumin, globulin and total protein, whereas serum glucose concentration and the activities of the serum alanine and aspartate aminotransferases were significantly (P < 0.05) increased during the sublethal exposures. Severe degeneration in the columnar epithelial cells and lamina propria, along with increased number of mucous cells observed in the intestine of the fish indicates sublethal toxicity of fullerene C60. The present findings led to the conclusion that the sublethal concentrations of fullerene C60 have a toxic impact on the fish A. testudineus by affecting the normal physiology, and thus the presence of this nanomaterial in the environment may affect the health status of the ecosystem. [ABSTRACT FROM AUTHOR]

New polymer composites were obtained by incorporating hybrid carbon modifiers into the poly(m-phenyleneisophthalamide) matrix consisting of a branch center (C60 fullerene) and 12 grafted hydrophobic chains: 6 polystyrene chains and 6 poly(tert-butyl methacrylate) chains. The physico-chemical and transport properties of the membranes were studied for the purification of butan-1-ol from water impurities. [ABSTRACT FROM AUTHOR]

The electric field can change the absorption of fullerene C60 to different wavelengths of light by affecting the vibrational modes and electronic transitions. The IR spectrum of fullerene C60 under the strong electric field is studied on B3LYP/6-31G* basis set using density function theory. With the external electric field decreasing, silent modes Hg(1), Ag(1), Gu(2), Hg(5), Ag(2), Hu(7) become active. Meanwhile, UV-Vis spectrum, the excitation energy, excitation wavelength and oscillator strength of first fourteen excited states of fullerene C60 under the field are also studied in B3LYP/6-31G* basis set using time-dependent density functional theory. With the electric field increasing, the absorption peak of fullerene C60 occurs then shifts towards the long-wave region. The excitation energy decrease and the excitation wavelength increase correspondingly, and external electric field makes fullerene C60 absorb energy from 1.01 to 2.31 eV in theory. The energy gap decreases drastically from 2.74 to 1.38 eV, which contributed to tune the energy gap of fullerene C60 by the effect of the electric field in a wide range. It is possible to use electric field to tune fullerene C60 into new energy storage material. [ABSTRACT FROM AUTHOR]

Three-component condensation of substituted 4-oxochromene-3-carbaldehydes with sarcosine and fullerene C60 afforded 2′-(4-oxochromen-3-yl)-1′-methyl-2′,5′-dihydro-1′H-pyrrolo[3′,4′:1,9](C60-Ih)[5,6]fullerenes. The structure of the synthesized compounds was studied by 1H and 13C NMR spectroscopy, including 1H–1H COSY and 1H–13C HMQC experiments. [ABSTRACT FROM AUTHOR]

The bi-functional carbazole-based photorefractive polyphosphazenes with different content of C60-doped were fabricated. The glass transition temperature (Tg) of these polymer composite materials was determined using a differential scanning calorimetric (DSC) method. According to the DSC measurement results with different heating rates, the variation of Tg and the active energy of glass transition (Eg) were analyzed in detail. The analysis results indicate that the transition region shifts to higher temperatures with increasing heating rate, and C60 content (below 1.0wt%) can influence the Tg of photorefractive polyphosphazenes. The Tg first increases and then decreases with the C60 content (below 1.0wt%). The probable causes of the influence of C60 on Tg was proposed. [ABSTRACT FROM AUTHOR]

Nanostructured composite materials (NCMs) based on Al-Mg alloy AMg6 (1560) modified with fullerene C60 are obtained by milling of initial materials in a high-energy planetary ball mill and the subsequent hot extrusion of powder mixtures. The structure, phase composition, and physical and mechanical properties of NCMs obtained are studied. It is shown that introduction of 0.3 wt % of fullerene C60 into NCMs prevents agglomeration of the particles during milling, intensifies the particle size reduction, and makes it possible to obtain an average aluminum crystallite size less than 50 nm. After consolidation of the powder mixtures by direct hot extrusion, the obtained materials demonstrate an increase in tensile strength up to 820 MPa and in bending strength up to 1.11 GPa. In this case, the density of NCMs is 2.61 g/cm3, which provides a value of the specific strength on the level of titanium alloys and fiberglass. [ABSTRACT FROM AUTHOR]

Cu-C60 nanocomposite thin films are synthesized by co-deposition restive heating method on glass, silicon, and TEM grid substrates. Rutherford backscattering spectroscopy (RBS) analysis is used for determining the composition of Cu and thickness of thin film which one found to be ∼13 at% and ∼28 nm, respectively. The deposited thin films are irradiated with 100 keV Ag ion at different fluences ranging from 1 × 1014 to 3 × 1016 ions/cm2. Being of low energy, Ag ions got implanted in SiO2 substrate up to a depth of 30-40 nm that results in wide surface plasmon resonance (SPR) band in combination with SPR of Cu nanoparticles. UV-visible absorption spectroscopy demonstrates the SPR peak arises due to copper nanoparticles embedded in fullerene C60 matrix on irradiation of nanocomposite thin film and its variation under implantation of Ag nanoparticles in SiO2 substrate. Structural modifications due to ion irradiation are analyzed by Raman and transmission electron microscopy (TEM). Raman spectroscopy study reveals the transformation of fullerene C60 into amorphous carbon (a-C) with increasing fluence. Variation in particle distribution is observed under TEM. The average particle sizes are found to be ∼4 ± 0.7 and ∼6 ± 0.4 nm for pristine and 100 keV Ag ion-irradiated thin films, respectively. Atomic force microscopy (AFM) confirms the increase in grain size with increase in roughness of nanocomposite thin films under the effect of implantation. X-ray photoelectron spectroscopy (XPS) confirms the presence of Cu and C from their chemical bonding in Cu-C60 nanocomposite thin films. [ABSTRACT FROM AUTHOR]

Raman and photoluminescence spectra of nanostructured ZnO films with adsorbed C60 molecules were studied. The possibility of intensive C60-ZnO electronic coupling forming in this composite was investigated. It is shown that such an electron coupling can be significantly enhanced by irradiating the composite with high intensity UV laser radiation (λ = 325 nm). [ABSTRACT FROM AUTHOR]

A complex of fullerene C and dihydroquercetin (DHQC) was synthesized. Its biological activity in a model system was studied using chemiluminometry. It was established that the C/DHQC complex possessed antioxidant activity, which prompted further investigation of its biological effects. The structure of the complex will be elucidated in a continuation of this work using analytical HPLC and NMR spectroscopy. [ABSTRACT FROM AUTHOR]

The properties of carbon films deposited by the radio frequency plasma sputtering of a fullerene C60 target were investigated to elucidate the dependence on the plasma power. A radio frequency argon plasma power ranging from 50 to 300W at a pressure of 1.3 Pa was applied for sputtering. This corresponds to a self-bias potential on the target ranging from −95 to −250 V and a maximum argon ion energy ranging from 240 to 575 eV. The analysis of the G and D peaks in the Raman spectra shows that the films are similar to tetragonal hydrogenated amorphous carbon annealed at 600–1,000 °C. The electron band structure of the carbon films deposited by the sputtering of C60 depends on the plasma power. The coating effect of these carbon films on the capacity performance of the silicon film electrode of lithium secondary batteries was significant in our experimental range. An electrochemical test revealed that such carbon thin film on the silicon electrode plays an important role in mitigating the capacity fading during the charge and discharge processes. The test revealed that the film formed at a plasma power of 300 W is the most effective. [ABSTRACT FROM AUTHOR]

To purify the mammalian cell membrane porphyrin binding proteins (PBP), an original affinity chromatographic technique is proposed. The method is based on the application of an agarose attached fullerene-porphyrin ligand connected to a polysaccharide gel matrix through the epoxy-cyclohexyl residue interface. A selective PBP-stationary phase coupling has been managed in a single column chromatographic run leading to a complete purification of the 17.6 kDa monomer protein from the rat myocardium mitochondria membranes. A synchronous pH and ionic strength linear gradients were used to separate this protein with a high specific affinity to the porphyrin K related structures from all non-specific sorption retained membrane proteins. [ABSTRACT FROM AUTHOR]

The introduction of pin-up oxygen on C60, such as in the oxidized fullerenes C60O and C60On, induced noticeable increase in the antioxidant activity as compared to pristine C60. The water-soluble inclusion complexes of fullerenes C60O and C60On reacted with linoleic acid peroxyl radical 1.7 and 2.4 times faster, respectively. [ABSTRACT FROM AUTHOR]

The literature data on the Gibbs energy of C60 fullerene dissolution in organic solvents of different classes are analyzed. The contributions of the functional groups (-CH3,-CH2-, >CH-, >C<,-OH,-Ph,-Napht, etc.) of solvent molecules to the Gibbs energy of C60 fullerene solution were calculated based on the additive group model. The effects of different functional groups on the solution process are discussed. [ABSTRACT FROM AUTHOR]

The formation of secondary fullerene ozonides (SFOs) in the ozonolysis of C60 solutions in CCl4 has reliably been determined for the first time; SFOs are accumulated during the whole ozonolysis time as a suspension in CCl4. Hydrolysis of the SFOs results in chemiluminescence (CL) ( I max = 2.65·108 photon s−1 mL−1), whose spectra contain maxima at 558, 608, and 685 nm. The most probable CL emitters are excited fullerene polyketones. Hydrogen peroxide was identified as a stable hydrolysis product of the SFOs by the color reaction with diphenylcarbazide and CL arisen upon the addition of an aqueous solution of FeSO4·9H2O to the hydrolyzate of the SFO. Chemiluminescence upon hydrolysis is a selective test for SFOs and allows one to find them in a complex mixture of the ozonolysis products of C60. The rate constant and activation energy of SFO hydrolysis were determined from the kinetic measurements of CL. For SFO hydrolysis several probable reactions were proposed, including the formation of the CL emitters, and their heat effects were estimated using the PM3/RHF and AM1/RHF semiempirical methods for one-and two-cage model structures of SFOs. [ABSTRACT FROM AUTHOR]

Quenching of electronically excited states of Ln3+* ions generated upon photoexcitation of toluene solutions of Ln(acac)3·H2O (Ln = Tb, Eu) complexes by C60 fullerene at 293 K was detected and investigated. The dependences of quenching efficiency on C60 concentration obtained from data on the decrease in the photoluminescence intensity and Ln3+* lifetimes obey the Stern-Volmer law. Quenching is due to inductive-resonant energy transfer from Ln3+* to C60 fullerene. The bimolecular rate constants for quenching, the overlap integrals of the Ln3+* photoluminescence spectra with the C60 absorption spectra, and the critical energy transfer distances were determined. No sensitized luminescence of C60 in the system studied was detected. [ABSTRACT FROM AUTHOR]

The reduction of fullerene C60 by Zn and Mg in DMF was studied both in the presence and absence of KOH. Fullerene C60 was reduced in these systems to form the C60 n– ( n = 1, 2, and 3) anions. The anions were detected by optical and ESR spectroscopies. It was found that Mg reduced C60 to the monoanion, Mg/KOH and Zn reduced C60 to the dianion, and Zn/KOH reduced C60 to the trianion. Like KCN, potassium hydroxide adds to fullerene upon interaction with C60 in DMF. The reaction of C60 with KOH in benzonitrile was accompanied by the generation of the fullerene monoanion. A possible mechanism of the formation of fullerene monoanions in the presence of KOH is discussed. The degradation of the C60 n– anions in air was studied. [ABSTRACT FROM AUTHOR]

New fullerenopyrrolidines were synthesized by the three-component reactions of fullerene C60, N-methylglycine, and aromatic aldehydes, viz., N, N-bis(2-chloroethyl)-4-aminobenzaldehyde, N-(2-chloroethyl)- N-methyl-4-aminobenzaldehyde, indole-3-carbaldehyde, 4-phenylbenzaldehyde, and anthracene-9-carbaldehyde. The structures of the resulting compounds were established by spectroscopic methods. [ABSTRACT FROM AUTHOR]

Paramagnetic products of chemical (by diazabicycloene derivatives) and electrochemical reduction of the dicarbethoxy derivative and phosphorylated methane[60]fullerenes were studied by ESR. In all cases, one-electron reduction affords radical anions ( g = 1.9998—1.9999, Δ H = 0.20—0.28 mT), and further reduction produces the secondary radicals ( g = 2.0004—2.0010, Δ H = 0.020—0.028 mT). The rate constants for formation and decay of the radical anions in chemical reduction depend slightly on the nature of the reducing agent and substituents in the methanofullerenes. The retro-Bingel reaction occurs during two-electron reduction. [ABSTRACT FROM AUTHOR]

The products of reaction of fullerene C60 with fuming sulfuric acid were precipitated from a solution with water and triethylamine and studied by IR and ESR spectroscopies. A comparison of the obtained data with the spectra of fullerene, dimers C120 and C120O, and fullerene polymers produced by photopolymerization allowed the conclusion that fullerene polymers were formed by fullerene oxidation with fuming sulfuric acid. [ABSTRACT FROM AUTHOR]

The problem of existence of η4-π-complexes of transition metal atoms with Ñ60 fullerene and its simplest bowl-shaped hydrocarbon precursor, corannulene (Ñ20H10), is discussed in the framework of the HF/3-21G and DFT/TZ2P methods. The molecular structures of corannulene and Ñ60 fullerene derivatives, namely, C20H14, C20H16, C60H4, and C60H6 were simulated. These molecules can form stable η4-π-complexes C20H14Fe(CO)3, C20H16Fe(CO)3, C60H4Fe(CO)3, and C60H6Fe(CO)3 in which the Fe atom interacts with C atoms of a fulvene-like or butadiene-like conjugated fragment of the hydrocarbon ligands. The energies of the η4-π-bonds in the complexes under study were compared with the corresponding bond energies in the classical complexes C4H6Fe(CO)3 and C5H6Fe(CO)3. The geometric parameters of C4H6Fe(CO)3 and C5H6Fe(CO)3 obtained from DFT calculations are close to the experimental values. Stabilities of the η4-π-complexes studied and their η5-π-analogs were compared. [ABSTRACT FROM AUTHOR]

The ability of cyclopentadienyl type derivatives of corannulene C20H10 and fullerene I h -C60 to form η5-π-complexes and the problem of their existence is discussed. MNDO/PM3 calculations of half-sandwich complexes η5-π-MC20H15, η5-π-MC20H, η5-π-MC60H5, η5-π-MC60H5 and sandwich complexes 2η5-π-M(C20H15)2, 2η5-π-M(C20H15)2, 2η5-π-M(C60H5)2 (M=Si, Ge, Sn, Pb) were performed. For all systems studied, local minima were found on corresponding potential energy surfaces and the heats of formation, geometric parameters, and distributions of effective atomic charges were calculated. Sandwich complexes are most likely to exist with M=Si and Ge. The energy and geometric characteristics of η5-π-complexes of corannulene were compared with those of η5-π-complexes of fullerene I h -C60. It was concluded that the results of quantum-chemical calculations of sandwich type corannulene derivatives can be used for simulation of the geometry and electronic structure of analogous complexes of fullerene I h -C60. [ABSTRACT FROM AUTHOR]

The product of the interaction of fullerene C60 with dibenzenechromium (DBC) was studied by ESR and IR spectroscopy. The ESR spectrum contains a signal of the radical cation DBC+. A signal of the C60 − anion is virtually absent, which is most likely related to its broadening. The IR spectrum contains bands characteristic of the DBC+ cation in the (DBC)I molecule and four bands characteristic of C60 −. The data obtained indicate the interaction of C60 molecules with the environment in the crystal structure of the complex. [ABSTRACT FROM AUTHOR]

An efficient catalytic method for cycloaddition of diazo amides to fullerene C 60 in the presence of the three-component catalyst Pd(acac) 2-PPh 3-Et 3Al was developed. The yields and selective formation of the target cycloadducts do not depend on the structure of the starting diazo compound. [ABSTRACT FROM AUTHOR]

An efficient catalytic method for cycloaddition of diazo amides to fullerene C 60 in the presence of the three-component catalyst Pd(acac) 2-PPh 3-Et 3Al was developed. The yields and selective formation of the target cycloadducts do not depend on the structure of the starting diazo compound. [ABSTRACT FROM AUTHOR]

The reactions of fullerene C60 with bromo(dimethoxyphosphoryl)acetates in the presence of NaH in toluene afforded alkoxycarbonyl(dimethoxyphosphoryl)methanofullerenes whose structures were established by UV, IR, and 1H, 13C, and 31P NMR spectroscopy. [ABSTRACT FROM AUTHOR]

Increased interest in fullerene C60 and derivatives in recent years implies an intensification of their environmental spread. Yet, the potential risks for living organisms are largely unknown, including the interaction of C60 with fungal organisms. This may be especially relevant for mycotoxigenic fungi since C60 may both scavenge and produce reactive oxygen species (ROS), and oxidative stress induces mycotoxin production in fungi. Therefore, this study examined effects of environmentally plausible concentrations of C60 (0, 10, 50, and 100 ng/mL) on Aspergillus flavus growth and aflatoxin production in culture media. In addition, ROS-dependent oxidative stress biomarkers—thiobarbituric acid reactive substances (TBARS), reduced and oxidised glutathione ratio, superoxide dismutase isoenzymes, catalase, glutathione peroxidase, and glutathione reductase were determined in mycelia. Nanoparticles of fullerene C60 (nC60) did not exhibit strong antifungal activity against A. flavus. At the same time, nC60 caused an antiaflatoxigenic effect at 10–100 ng/mL, and 50 ng/mL unexpectedly enhanced aflatoxin production. The TBARS content, reduced and oxidised glutathione ratio, and copper, zinc superoxide dismutase activity suggest that 10 ng/mL nC60 exerted antioxidative action and reduced aflatoxin B1 production within fungal cells. Detected prooxidative effects of 50 ng/mL fullerene exceeded cellular defenses and consequently enhanced aflatoxin B1 production. Finally, the results obtained with 100 ng/mL nC60 point to prooxidative effects, but the absence of increase in aflatoxin output may indicate additional, presumably cytotoxic effects of nC60. Thus, a range of rather low levels of nC60 in the environment has a potential to modify aflatoxin production in A. flavus. Due to possible implications, further studies should test these results in environmental conditions. [ABSTRACT FROM AUTHOR]