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81.
82.
A Synthetic Transcriptional Activator of Genes Associated with the Retina in Human Dermal Fibroblasts 下载免费PDF全文
83.
P.Y. Raval P.R. Pansara A.R. Makadiya N.H. Vasoya S.N. Dolia K.B. Modi 《Ceramics International》2018,44(15):17667-17674
The consequences of high energy mechanical milling, microwave-assisted heating and rapid thermal cooling on magnetic ordering in polycrystalline CaCu3Ti4O12 cubic perovskite have been investigated by means of X-ray powder diffractometry (300?K), dc magnetization in field – cooled and zero – field cooled modes (H = 100?Oe and 1000?Oe, T?=?5–300?K) (M – T curves) and M – H loop characteristics (T?=?5?K and 300?K, Hmax = 70?kOe). The M – T curves of unmilled and 16?h milled samples show pure antiferromagnetic and weak ferromagnetic ordering, respectively, 1?h and 6?h milled samples demonstrate the coexistence of both the phases while microwave-assisted and quenched samples exhibit classic antiferromagnetic transition and a low temperature paramagnetic–like contribution with different weights, well supported by the M – H loop characteristics. The observed transformations in the magnetic ordering are attributed to the ball-milling induced stress which curtails hybridization of empty Ti-3d orbitals with Cu-3d and O-2p orbitals and secondary phase formation. Oxygen vacancies associated with bound magnetic polarons originate ferromagnetism in the milled samples while unpaired electrons inhabited at the empty sites are the cause of paramagnetic centers. The low-temperature Curie – tail in M – T curve for quenched and microwave assisted samples is attributed to Ti3+ cations. 相似文献
84.
V.I. Popkov O.V. Almjasheva V.N. Nevedomskiy V.V. Panchuk V.G. Semenov V.V. Gusarov 《Ceramics International》2018,44(17):20906-20912
Formation and structural transformations of yttrium orthoferrite crystals have been studied using X-ray diffractometry, Mössbauer spectroscopy and transmission electron microscopy combined with electron microdiffraction. Said processes have been studied under heat treatment of glycine-nitrate combustion products. There have been identified formations of three structural yttrium orthoferrite modifications – amorphized hexagonal <h1>-YFeO3 (P63cm) and nanocrystalline hexagonal h2-YFeO3 (P63/mmc), as well as nanocrystalline orthorhombic o-YFeO3 (Pbnm), which are selectively formed depending on available three-dimensional confinements. Based on the analysis of changes in the fluid and size composition formulation, it has been proposed mechanism for formation and transformation of YFeO3 nanocrystals, including growth stage of h2-YFeO3 crystals due to amorphized phase of <h1>-YFeO3 up to critical size of about 15?nm and their subsequent transformation into orthorhombic form o-YFeO3. 相似文献
85.
Semiconductors - Long-wavelength acoustic phonon-assisted relaxation rates for the excited 1s(T), 2p0, 2s, 3p0, 2p±, 4p0, and 3p± states of antimony donors in a germanium crystal are... 相似文献
86.
87.
Technical Physics Letters - Specific features of monitoring the state of a flowing medium by method of nuclear magnetic resonance (NMR) are considered. An approach to studying the state of a... 相似文献
88.
Fominski V. Yu. Nevolin V. N. Fominski D. V. Romanov R. I. Gritskevich M. D. 《Technical Physics Letters》2020,46(1):83-86
Technical Physics Letters - We present the results of a comparative investigation of the friction and wear characteristics of MoSx and MoSex coatings in an oxidizing medium (argon–air... 相似文献
89.
Kovchavtsev A. P. Aksenov M. S. Nastov’yak A. E. Valisheva N. A. Gorshkov D. V. Sidorov G. Yu. Dmitriev D. V. 《Technical Physics Letters》2020,46(5):469-472
Technical Physics Letters - The C–V characteristics of Au/Al2O3/In0.52Al0.48As and Au/SiO2/In0.52Al0.48As metal–insulator–semiconductor structures have been studied. It has been... 相似文献
90.