Structure and magnetism of copper substituted cobalt ludwigite Co₃O₂BO₃

The single crystals Co₃O₂BO₃ with partial (4%) substitution of Co by Cu ions were synthesized by the flux technique. X-ray diffraction and magnetic properties investigations were carried out. The x-ray diffraction meas-urements have shown that Cu clearly prefers only one from four nonequivalent crystallographic positions with the smallest electric field gradient. The ferrimagnetic ordering near TN = 43 K and high magnetic hardness in this magnetic phase are similar to Co₃O₂BO₃. The small reduction of the effective magnetic moment was revealed under copper substitution

APPLICATION OF DC ATMOSPHERIC PRESSURE PLASMA JETS FOR INACTIVATION OF MICROORGANISMS CONSORTIUMS

Experimental results for inactivation of microorganism test strains of S. aureus, E. coli, P. aeruginosa separately and in such consortium by air plasma jet are presented. For monocultures of S. aureus, E. coli, P. aeruginosa the characteristic D-times are practically the same and are around 1.5 min, while for the consortium these is 3 min.57-5

Spin state crossover in Co3BO5

We have investigated the spin and oxidation states of Co in Co3BO5 using x-ray magnetic circular dichroism (XMCD) and dc magnetic susceptibility measurements. At low temperatures, XMCD experiments have been performed at the Co K-edge in Co3BO5 and Co2FeBO5 single crystals in the fully ferrimagnetically ordered phase. The Co (K-edge) XMCD signal is found to be related to the Co2+ magnetic sublattices in both compounds, providing strong experimental support for the low-spin (LS) Co3+ scenario. The paramagnetic susceptibility is highly anisotropic. An estimation of the effective magnetic moment in the temperature range 100-250 K correlates well with two Co2+ ions in the high-spin (HS) state and some orbital contribution, while Co3+ remains in the LS state. The crystal structure of the Co3BO5 single crystal has been solved in detail at the T range 296-703 K. The unit cell parameters and volume show anomalies at 500 and 700 K. The octahedral environment of the Co4 site strongly changes with heating. The generalized gradient approximation with Hubbard U correction calculations have revealed that, at low-temperatures, the system is insulating with a band gap of 1.4 eV, and the Co2+ ions are in the HS state, while Co3+ are in the LS state. At high temperatures (T > 700 K), the charge ordering disappears, and the system becomes metallic with all Co ions in 3d7 electronic configuration and HS state. © 2021 American Physical Society

APPLICATION OF DC ATMOSPHERIC PRESSURE PLASMA JETS FOR INACTIVATION OF MICROORGANISMS CONSORTIUMS

57-57Experimental results for inactivation of microorganism test strains of S. aureus, E. coli, P. aeruginosa separately and in such consortium by air plasma jet are presented. For monocultures of S. aureus, E. coli, P. aeruginosa the characteristic D-times are practically the same and are around 1.5 min, while for the consortium these is 3 min

Low-temperature magnetic behavior of the rare-earth cobaltites GdCoO 3 and SmCoO3

The temperature and magnetic field dependences of the static magnetization of the polycrystalline rare-earth cobaltites GdCoO3 and SmCoO 3 have been measured. It is shown that, below room temperature, the magnetization of both compounds derives primarily from the rare-earth ion paramagnetism. The GdCoO3 and SmCoO3 compounds have been found to differ substantially in magnetic behavior, which can be traced to differences in their electronic shell structures. The magnetic behavior of GdCoO3 is close to that of an array of free Gd3+ ions, whereas in SmCoO3 the deviation from the free-ion properties is very large because of the Sm3+ ground state being crystal-field split. Van Vleck magnetic susceptibility measurements of SmCoO3 suggest that the splitting is ∼ 10 K. © 2007 Pleiades Publishing, Ltd

Effect of strontium and barium doping on the magnetic state and electrical conductivity of GdCoO3

A coordinated investigation of the magnetic and electrical properties of polycrystalline cobalt oxide compounds CdCoO3, Gd 0.9Ba0.1CoO3, and Gd0.9Sr 0.1CoO3 is carried out. Undoped GdCoO3 reveals a low conductivity; a magnetic moment of 7.4 μB per molecule, which is less than the theoretical value for the Gd3+ ion; and an asymptotic Curie temperature of -6 K. Doping GdCoO3 with barium and strontium to substitution of 10 at. % Gd brings about an increase in the conductivity and magnetic transitions at T = 300 K for Gd0.9Ba 0.1CoO3 and T = 170 K for Gd0.9Sr 0.1CoO3. The magnetization anomalies imply the formation of magnetic clusters. The behavior of the electrical conductivity at high temperatures suggests a variable activation energy. At low temperatures, Mott hopping conduction sets in. © 2007 Pleiades Publishing, Ltd

Effect of small doses of naloxone on the pulsatile secretion of prolactin in the crossbreed ewe during the non-breeding season

A coordinated investigation of the magnetic and electrical properties of polycrystalline cobalt oxide compounds CdCoO3, Gd 0.9Ba0.1CoO3, and Gd0.9Sr 0.1CoO3 is carried out. Undoped GdCoO3 reveals a low conductivity; a magnetic moment of 7.4 ?B per molecule, which is less than the theoretical value for the Gd3+ ion; and an asymptotic Curie temperature of -6 K. Doping GdCoO3 with barium and strontium to substitution of 10 at. % Gd brings about an increase in the conductivity and magnetic transitions at T = 300 K for Gd0.9Ba 0.1CoO3 and T = 170 K for Gd0.9Sr 0.1CoO3. The magnetization anomalies imply the formation of magnetic clusters. The behavior of the electrical conductivity at high temperatures suggests a variable activation energy. At low temperatures, Mott hopping conduction sets in. " 2007 Pleiades Publishing, Ltd.",,,,,,"10.1134/S1063783407080161",,,"http://hdl.handle.net/20.500.12104/41011","http://www.scopus.com/inward/record.url?eid=2-s2.0-34548088088&partnerID=40&md5=e3e41326b40e3f6a7fda1d057dcf655f",,,,,,"8",,"Physics of the Solid State",,"149

Contribution of Co 3+ ions to the high-temperature magnetic and electrical properties of GdCoO 3

The temperature dependence of the static magnetization of polycrystalline rare-earth cobaltite GdCoO 3 is measured in the temperature range 2-800 K. The magnetic behaviors of GdCoO 3 and Gd 3+ are found to be different at temperatures above room temperature, which is caused by the appearance of a contribution from Co 3+ ions at high temperatures. The temperature dependence of the magnetic susceptibility of GdCoO 3 is determined by the magnetization of rare-earth gadolinium ions and the additional paramagnetic contribution induced by the thermally excited magnetic terms of Co 3+ ions. The LDA + GTB method is used to calculate the electronic structure of GdCoO 3 in the temperature range 0-300 K with allowance for strong electron correlations. The energy spectrum of GdCoO 3 is found to have intragap states that decrease the dielectric gap width with increasing temperature. � Pleiades Publishing, Inc., 2012

Magnetic fields in Proto Planetary Nebulae

The X-ray diffraction, magnetization and electrical conductivity measurements for Gd0.9A0.1CoO3-? (A=Ba, Sr) have been made. The complicated magnetic behavior, including the paramagnetic-ferromagnetic-antiferromagnetic and paramagnetic-ferromagnetic transitions, was found for Ba- and Sr-doped samples. The gradual insulator-metal transitions were observed in a wide temperature range T=600-800 K. The complex magnetic and transport data could be explained on the basis of the structural phase separation. " 2009 Elsevier B.V. All rights reserved.",,,,,,"10.1016/j.jmmm.2008.11.087",,,"http://hdl.handle.net/20.500.12104/42640","http://www.scopus.com/inward/record.url?eid=2-s2.0-61849143325&partnerID=40&md5=90f25c0a8cff31749916101a9d8284bb",,,,,,"9",,"Journal of Magnetism and Magnetic Materials",,"126