Аннотация. Проведено экспериментальное исследование на лабораторных животных по изучению эффективности адресной доставки мази левомеколь с помощью магнитных наночастиц и внешнего магнитного поля при ...термических ожогах. В исследовании принимало участие 20 крыс с двумя очагами ожога. Крысы были разделены на 4 группы: без лечения, терапия с использованием мази левомеколь, лечение с использованием наночастиц, мази левомеколь и внешнего магнитного поля и только магнитотерапии. При гистологическом исследовании на 14-е сутки во всех группах в зоне термического повреждения кожи были отмечены признаки глубокого ожога III и IV степени с распространением некроза на всю глубину дермы и на мышцы. В группе с наночастицами, мазью левомеколь и магнитным полем на фоне уменьшения воспаления отмечалось очаговое появление грануляционной ткани. Таким образом, гистологические исследования ожогового раневого процесса лабораторных животных показали, что использование инновационного биологически активного ранозаживляющего средства на основе наночастиц в сочетании с мазью левомеколь улучшает регенерацию тканей и приводит к ускорению эпителизации, что в целом повышает результаты лечения ожоговой раны. Использование внешнего магнитного поля способствует адресной доставке лечебного нанокомплекса и поддержанию оптимальной концентрации препарата в ране.
The features of the FeAsS arsenopyrite crystal structure disordering occurred in geological conditions were studied by elemental analysis, X-ray diffraction and Mossbauer techniques using natural ...samples. There were selected and studied three practically single-phase polycrystalline samples of Blagodatnoe and Olimpiada ore deposits (Krasnoyarsk region) with the chemical composition close to stoichiometry (I), with excess sulfur (II) and arsenic (III). The Mossbauer (NGR) study detected the presence of the three forms of Fe(2+) in the substance. The first was associated with octahedral iron environment of As3S type, the second with S6 and third with As6 forms conventionally associated with ordered arsenopyrite and FeS2, FeAs2 minerals. According to NGR data the iron atoms at 95 % were in the main form in the sample (I). Other forms were present about in equal parts. There were detected 73 % and 56 % of iron in its basic form for samples (II) and (III) respectively with FeS2, FeAs2 dominated as by-forms. X-ray powder crystal structure refinement was carried out in Space group P21/c. It was established that the iron atoms were in cationic positions of the arsenopyrite. Additional crystallographic positions of iron were not detected. The structure variation mainly occurred in the anion sublattice disordering the primary iron coordination from FeAs3S3 to the condition described as Fe(As3-x4 Sx)(S3-yAsy). It was established that the mutual substitution of anions was accompanied by a small shift of the atomic positions due to the difference in the interatomic distances of Fe-S and Fe-As. Disordered condition admits the predominance of one of the anions. As a result, there are the set of the iron atom states with different composition and spatial configuration of the substituents in the coordination sphere in the real crystal. The disordering coordination of iron atoms obtained from X-ray diffracted data quantitatively corresponds to the data of NGR spectroscopy.
Electronic and magnetic states of Fe ions in CoFeBO Knyazev, Yurii V; Kazak, Natalia V; Zhandun, Vyacheslav S ...
Dalton transactions : an international journal of inorganic chemistry,
07/2021, Letnik:
5, Številka:
28
Journal Article
The ludwigite Co
2
FeBO
5
has been studied experimentally using
57
Fe Mössbauer spectroscopy and theoretically using DFT + GGA calculations. The room-temperature Mössbauer spectra are composed of ...four quadrupole doublets corresponding to the high-spin Fe
3+
ions in octahedral oxygen coordination. All components undergo splitting below 117 K due to the magnetic hyperfine fields. The DFT + GGA calculations performed for three models of Fe ion distributions have revealed that the ground state corresponds to the "Fe4(HS)" model with the high-spin Fe
3+
ions located at the M4 site and the high-spin Co
2+
ions located at the M1, M2, and M3 sites. A ferrimagnetic ground state, with the Co and Fe magnetic moments being nearly parallel to the
b
-axis and a total magnetic moment of
circa
1.1
μ
B
f.u.
−1
, was found. The other Fe distributions cause an increase in the local octahedral distortions and transformation of the spin state. The calculated quadrupole splitting values are in good agreement with the experimental values obtained by Mössbauer spectroscopy.
The ferrimagnet Co
2
FeBO
5
has been studied experimentally using
57
Fe Mössbauer spectroscopy and theoretically using DFT + GGA calculations.
β-Cu3Fe4(VO4)6 single crystals were synthesized. The X-ray, magnetic, Mössbauer, and EPR investigations of the crystals were fulfilled. It is established that single-crystal β-Cu3Fe4(VO4)6 is a spin ...glass at low temperatures. Freezing temperature varies considerably depending on the orientation of the magnetic field relative to the crystal axes. Spin-glass state is confirmed by the relaxation of the magnetization.
Physicochemical properties of two calcium aluminosilicate materials, after reducing in the hydrodynamic rotary generator in supercavitation mode, were studied. The samples are the crystal ceramic ...foam, based on Kansko-Achinsk, lignite-ash and the porous glass material obtained from low-manganese, nonmetallic feed. X-ray phase analysis, EPR-method, NPR-method (the Mossbauer Effect) and optical microscopy were used. It was found that the material is changing its stucrure in a hydrodynamic dispersion process, caused by high-cavitation. The nature of the changes depends on its initial state.
A series of Fe sub(1-x) Co sub(x) Se sub(1.09)(x= 0 to 1) nanoparticles were synthesized by thermal decomposition method. Particles in composition range Fe sub(0.5) Co sub(0.5) Se sub(1.09) to CoSe ...sub(1.09) crystallized in monoclinic structure of Co sub(6.8) Se sub(8), while FeSe sub(1.09) crystallized in hexagonal structure of FeSe achavalite. Magnetization dependences on temperature and external magnetic field reveal complicated magnetic behavior and correspond to the sum of paramagnetic and superparamagnetic response. Mossbauer spectra contain several paramagnetic doublets with parameters corresponding to nonequivalent positions of divalent and trivalent iron cations with low spin. The nonequivalent positions appeared due to inhomogeneous distribution of Co ions or metal vacancies in iron surrounding.
β-Cu3Fe4(VO4)6 single crystals were synthesized. The X-ray, magnetic, Mössbauer, and EPR investigations of the crystals were fulfilled. It is established that single-crystal β-Cu3Fe4(VO4)6 is a spin ...glass at low temperatures. Freezing temperature varies considerably depending on the orientation of the magnetic field relative to the crystal axes. Spin-glass state is confirmed by the relaxation of the magnetization.
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