In this article, we present a new Co2FeSi glass-coated microwire obtained by Taylor-Ulitovsky technique with nanocrystalline structure consisting of a mixture of bcc phase (lattice parameter, ...a = 5.640 Å, crystalline grain size, Dg = 17.8 nm) in as-prepared sample. The annealing temperature was fixed at 873 K, and the annealing time was 1 and 6 h. The annealing resulted in a significant increase of such nano-grains up to (31.6 nm). Perfect square hysteresis loops have been observed in all annealed samples at a wide temperature range (55–400 K) that are not seen in the as prepared sample. The thermal magnetic behavior for the annealed samples shows dramatic magnetic behavior at low temperature. Large irreversibility magnetic behavior with a blocking temperature (Tb = 150 K) has been observed for annealed sample for 1 h. Critical temperatures of 155 K and 105 K have been detected for annealed samples for 1 h and 6 h, respectively, where the behavior of M−H loops, coercivity and remanence changed. Below the critical point the M−H shows wasp-waisted, multistep magnetic behavior and complex magnetic reversal mechanism is supposed. The anomalous magnetic behavior is due to the coexistence of the ordered and disordered phases induced by annealing conditions below the room temperature. The difference in the magnetization behaviour, remanence, and coercivity values for Co2FeSi glass-coated microwires samples indicates the influence of internal stresses created by the presence of the glass coating. These finding opens the door to design spintronic devices based on the magnetization switching.
In this paper we provide results on effect of post-processing on magnetic properties (giant magnetoimpedance, GMI, effect and domain wall dynamics) of Fe71.7B13.4Si11Nb3Ni0.9 glass-coated microwire ...with metallic nucleus diameter d = 103 μm and total diameter D = 158 μm prepared by Taylor-Ulitovsky method. Amorphous structure of as-prepared wires is confirmed by X-ray diffraction and electronic microscopy.
As-prepared glass-coated wires present relatively low GMI ratio (about 50% at 500 MHz) and relatively low coercivity (about 25 A/m). Additionally, as-prepared sample present rectangular hysteresis loop and fast single domain wall propagation with domain wall mobility of about 11,9 m2/As. After annealing (either under tensile stress or without stress) we observed considerable improvement of the GMI ratio (from 50% up to 220% at 200 MHz) and domain wall mobility up to 15,5 m2/As. Observed GMI effect and domain wall mobility improvement has been attributed to the stresses relaxation and creep anisotropy.
We demonstrated that the Taylor-Ulitovsky technique is suitable for preparation of “thick” Fe based amorphous microwires with good magnetic properties and GMI effect suitable for industrial applications.
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•Preparation of thick glass-coated amorphous microwires.•Improvement of GMI effect of microwires by -annealing.•Fast single domain wall propagation with domain wall mobility of about 11,9 m2/As.•Enhancement of domain wall propagation by annealing.•Change of Hysteresis loop of microwires from rectangular to linear after stress annealing.•Enhanced GMI ratio of thick microwires in a wide frequency range.
In this article, we studied the effect of annealing (600 °C for 1 h) and the applied magnetic field from 50 Oe to 20 kOe of Co2FeSi glass-coated microwires with ordered L21 structure prepared by ...Taylor–Ulitovsky technique on the magnetic behavior. The as-prepared and annealed samples show a ferromagnetic behavior at the range of measuring temperature (5 to 400 K) and magnetic field (50 Oe to 20 kOe). M–H loops of as prepared sample do not show a squared shape. Meanwhile, perfectly squared hysteresis loops have detected for the annealed sample. In addition, annealed sample shows high magnetization M/M5K ratio, coercivity, and anisotropy field, as-compared to the as-prepared one. The annealed sample shows considerable irreversibility when the magnetic behavior changes with temperature upon the applied magnetic field at 50 and 200 Oe. Such irreversibility does not found in the as-prepared sample measured at the same magnetic field due to mixed amorphous and crystalline structure. By increasing the external magnetic field higher than 200 Oe and up to 20 kOe a gradual changing in the magnetic behavior has been detected where the irreversibility disappeared at applying magnetic field about 1 kOe and the magnetic behavior is totally change by increasing the external magnetic field up to the maximum 20 kOe. The difference in the magnetic behavior of the annealed glass-coated Co2FeSi glass-coated microwires indicates the effect of internal stresses induced by the presence of the glass-coating and the annealing-induced recrystallization.
•Improvement of GMI effect of Fe-rich microwires by stress-annealing.•Improvement of magnetic softness of Fe-rich microwires by stress-annealing.•Dependence of transverse magnetic anisotropy on ...stress, time and temperature of stress-annealing.•An increase in the outer domain sheath volume with transverse magnetic anisotropy upon stress-annealing.
Stress-annealing allows considerably modify magnetic properties of Fe-rich glass-coated microwires. Varying the stress-annealing conditions (temperature, time and stress applied during the annealing) we can observe either remarkable improvement of magnetic softness and giant magnetoimpedance (GMI) effect. Observed changes have been attributed to the transverse magnetic anisotropy. An improvement of the circumferential permeability in the surface layer of metallic nucleus is evidenced from observed magnetic softening and remarkable GMI effect rising. We assumed that stress-annealing leads to an increase in the outer domain sheath with transverse magnetic anisotropy rise in expense of inner axially magnetized core typically existing in as-prepared Fe-rich microwires. Consequently, stress annealing enabled us to design the magnetic anisotropy distribution beneficial for optimization of the GMI effect and magnetic softness of Fe-rich magnetic microwires.
Cytostatic chemotherapeutics provide a classical means to treat cancer, but conventional treatments have not increased in efficacy in the past years, warranting a search for new approaches to ...therapy. The aim of the study was, therefore, to obtain methacrylic acid (MAA) (co)polymers and to study their immunopharmacological properties. 4-Cyano-4-(dodecylsulfanylthiocarbonyl)sulfanyl pentanoic acid (CDSPA) and 2-cyano-2-propyl dodecyl trithiocarbonate (CPDT) were used as reversible chain transfer agents. Experiments were carried out in Wistar rats. The MTT assay was used to evaluate the cytotoxic effect of the polymeric systems on peritoneal macrophages. An experimental tumor model was obtained by grafting RMK-1 breast cancer cells. Serum cytokine levels of tumor-bearing rats were analyzed. The chain transfer agents employed in classical radical polymerization substantially reduced the molecular weight of the resulting polymers, but a narrow molecular weight distribution was achieved only with CDSPA and high CPDT concentrations. Toxicity was not observed when incubating peritoneal macrophages with polymeric systems. In tumor-bearing rats, the IL-10 concentration was 1.7 times higher and the IL-17 concentration was less than half that of intact rats. Polymeric systems decreased the IL-10 concentration and normalized the IL-17 concentration in tumor-bearing rats. The maximum effect was observed for a MAA homopolymer with a high molecular weight. The anion-active polymers proposed as carrier constituents are promising for further studies and designs of carrier constituents of drug derivatives.
This study provides new data on the whole-exome sequencing of a cohort of children with autistic spectrum disorders (ASD) from an underexplored Russian population. Using both a cross-sectional ...approach involving a control cohort of the same ancestry and an annotation-based approach involving relevant public databases, we explored exonic single nucleotide variants and copy-number variation potentially involved in the manifestation of ASD. The study results reveal new potential ASD candidate-variants found in the studied Russian cohort and show a high prevalence of common ASD-associated genomic variants, especially those in the genes known to be associated with the manifestation of intellectual disabilities. Our screening of an ASD cohort from a previously understudied population allowed us to flag at least a few novel genes (
,
,
,
,
, and
) regarding their potential involvement in ASD.
A strictly aerobic, Gram-stain-negative, rod-shaped, and motile bacterium, designated strain 16-SW-7, isolated from a seawater sample, was investigated in detail due to its ability to produce a ...unique α-galactosidase converting B red blood cells into the universal type blood cells. The phylogenetic analysis based on 16S rRNA gene sequences revealed that the strain 16-SW-7 is a member of the
genus
. The closest relatives of the environmental isolate were
KMM 638
and
KMM 3548
, with the plural paralogous 16S rRNA genes of 99.87-100% similarity. The strain 16-SW-7 grew with 1-10% NaCl and at 4-34°C, and hydrolyzed casein, gelatin, tyrosine, and DNA. The genomic DNA G+C content was 39.3 mol%. The prevalent fatty acids were C
ω7
, C
, C
ω8
, C
ω7
, C
, and C
3-OH. The polar lipid profile was characterized by the presence of phosphatidylethanolamine, phosphatidylglycerol, two unidentified amino lipids, and three unidentified lipids. The major respiratory quinone was Q-8. The finished genome of the strain 16-SW-7 (GenBank assembly accession number: GCA_005877035.1) has a size of 4,531,445 bp and comprises two circular chromosomes L1 and S1, deposited in the GenBank under the accession numbers CP040558 and CP040559, respectively. The strain 16-SW-7 has the ANI values of 98.2% with KMM 638
and KMM 3548
and the DDH values of 84.4 and 83.5%, respectively, indicating clearly that the three strains belonged to a single species. According to phylogenetic evidence and similarity for the chemotaxonomic and genotypic properties, the strain 16-SW-7 (= KCTC 52772 = KMM 701) represents a novel member of the species
. Also, we have proposed to reclassify
as a later heterotypic synonym of
based on the rules of priority with the emendation of the species.
The results of measurements of the exclusive cross section for the
e
+
e
−
→
D
(*)±
D
*∓
process near the open charm threshold with initial-state radiation are presented. The analysis is based on the ...experimental data collected with the Belle detector at energies
s
equal to ϒ(4S), ϒ(5S) production energies, and energies of the nearby continuum corresponding to an integrated luminosity of 951 fb
−1
. The accuracy of the measurements of the cross sections is twice higher in comparison with the previous results of the Belle collaboration. An angular analysis is performed for the final state
D
*
+
D
*
−
for the first time with the result that the cross section is decomposed into three components corresponding to the possible combinations of
D
*-meson polarizations in the final state.
•Correlation of the heat capacity at Curie temperature and the magnetostriction value.•Evaluation of activation energy of relaxation process from Curie temperature kinetics.•Improvement of GMI effect ...upon nanocrystallization of Finemet-type alloys.•Gradual degradation of the Tc peak upon nanocrystallizaton of amorphous phase.•Tc increase and ΔCpTc decrease upon relaxation of atomic structure of amorphous phase.
We studied the influence of annealing conditions on magnetic and thermal properties of Finemet-type alloys. The evolution of the Curie temperature, Tc, and the change of heat capacity in the vicinity of this magnetic transformation, ΔCpTc, were investigated using Differential Scanning Calorimetry, DSC. Relaxation of atomic structure of amorphous phase during the annealing was accompanied by an increase in Tc and decrease in ΔCpTc. Two relaxation processes with different mechanisms take place in amorphous state: topological ordering and chemical ordering. The study of the kinetics of relaxation process allows to estimate the apparent values of activation energy of both relaxation processes: 29 and 87 kJ/mol for ribbon, 37 and 112 kJ/mol for microwire. Precipitation of α-Fe nanocrystallites in amorphous phase leads to gradual degradation of the Tc peak. The Tc peak reduction is correlated to decrease of the amorphous phase as well as lowering of its magnetostriction. The influence of internal stress on the position and shape of the Curie peak was determined by comparing data for the ribbon-shaped alloys and glass coated microwires.
Considerable magnetic softening and giant magnetoimpedance effect under heat treatment is observed in the studied Finemet-type microwires. Changes in magnetic properties after heating are associated with devitrification and stresses relaxation. We also study the influence of internal stresses induced by glass coating on the magnetic properties of as-prepared and annealed microwires.
The results confirm the previously made conclusion that changes in the thermal and magnetic properties of Finemet-type alloys during heating are interrelated, since they are reflections of the fundamental characteristics of the material.
The numerical simulation approach of heat carrier mixing regimes in the T-junction shows that the RANS approach is beneficial for a qualitative flow analysis to obtain relatively agreed averaged ...velocity and temperature. Moreover, traditionally, the RANS approach only predicts the averaged temperature distribution. This mathematical model did not consider the temperature fluctuation variations important for the thermal fatigue task. It should also be emphasized that unlike the LES approach, the steady RANS approach cannot express a local flow structure in intense mixing zones. Nevertheless, apparently the adopted RANS approach should be used for assessing the quality of computational meshes, boundary conditions with the purpose to take LES for further numerical simulation.
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