In this work, the effect of ball milling of synthesized LiFe
5
O
8
ferrite powders on the microstructure and properties of ferrite ceramics was studied by XRD, laser diffraction and SEM analysis as ...well as thermal analysis. The mechanical milling of LiFe
5
O
8
was carried out in a Fritsch Pulverisette 7 planetary mill using the zirconia or steel grinding balls. The process of ferrite sintering was investigated using dilatometric analysis. In addition, ferrite ceramics electromagnetic properties, including magnetization, Curie point and electrical resistivity, were investigated. The results showed a strong difference in the structure of ferrite ceramics obtained from ferrite powders pre-milled by zirconia or steel grinding balls. Thus, the milling results in a decrease in the particle size of the ferrite powders to ultrafine range. The ferrite ceramics, obtained from powder milled by steel balls, is characterized by high density and low porosity as well as good electromagnetic properties and the main presence of a disordered β-LiFe
5
O
8
phase. However, the mechanical milling using zirconia balls leads to the contamination of ferrite by zirconia, resulting in the formation of β-LiFe
5
O
8
/ZrO
2
composite ceramics during sintering.
The speckle polarimeter is a facility instrument of the 2.5-mSAIMSU telescope that combines the features of a speckle interferometer and a polarimeter. The speckle polarimeter is designed for ...observations in several visible bands in the following modes: speckle interferometry, polarimetry, speckle polarimetry, and polaroastrometry. In this paper we describe the instrument design and the procedures for determining the angular scale of the camera and the position angle of the camera and the polarimeter. Our measurements of the parameters for the binary star HD 9165 are used as an example to demonstrate the technique of speckle interferometry. For bright objects the accuracy of astrometry is limited by the error of the correction for the distortion caused by the atmospheric dispersion compensator. At zenith distances less than 45◦ the additional relative measurement error of the separation is 0.7%, while the additional error of the position angle is 0.3°. In the absence of a dispersion compensator the accuracy of astrometry is limited by the uncertainty in the scale and position angle of the camera, which are 0.15% and 0.06°, respectively. We have performed polarimetric measurements of unpolarized stars and polarization standards. The instrumental polarization at the Cassegrain focus in the
V
band does not exceed 0.01%. The instrumental polarization for the Nasmyth focus varies between 2 and 4% within the visible range; we have constructed its model and give a method for its elimination from the measurements. For stars with an intrinsic polarization of less than 0.2% during observations at the Cassegrain focus the error is determined mainly by the photon and readout noises and can reach 5 × 10
−5
.
•A new method is developed quantitative phase control in soft ferrimagnetic materials.•The method is based on thermomagnetometric analysis of the samples in magnetic field.•This method compared to ...X-ray diffraction analysis is more precise.•The method was successfully tested on the LiTi and LiZn ferrites.
In this work, the method of quantitative ferrite phase control, which is based on thermomagnetometric analysis of the ferrite samples in magnetic field, was developed. The magneto-phase transitions in LiZn and LiTi ferrites with chemical formulas Li0.5(1x)Fe2.50.5xZnxO4 and Li0.5(1+x)Fe2.51.5xTixO4 were studied, and their phase compositions were analyzed by both the developed method and X-ray diffraction analysis. It was shown that the thermomagnetometry method compared to X-ray diffraction analysis allows to examine more precisely the magnetic phases in synthesized ferrites with inhomogeneous phase composition. However, a complex analysis, using both X-ray and thermomagnetometry methods, will be the most optimal in case of the formation of non-magnetic and poor magnetic phases.
The authors study the effect the dispersion of particles of synthesized nickel–zinc ferrite powder has on its structural and magnetic properties. Ferrite powder is fabricated using ceramic ...technology. The average particle size is varied by means of mechanical activation. The patterns of the formation of nickel–zinc ferrite’s properties are established via X-ray diffraction analysis, laser diffraction, and thermal analysis, depending on the modes of mechanical activation.
This article discusses the expected climate changes in Belarus as a result of two types of land transformation—rewetting degraded peatlands and increasing forest cover. The analysis was performed for ...the growing season (May–September) based on long-term earth remote sensing data, mesoscale modeling of atmospheric processes, and balance calculations using ERA5 reanalysis. It is shown that, as a result of waterlogging, the daytime temperature of the land surface for the southern part of Belarus (below the latitude of Minsk) decreases within 1.5°С due to increased evaporation and, for the northern part, 0.5 increased due to albedo regularity. At night, waterlogging, depending on the soil and climatic conditions, can cause both an increase and decrease a specific value of the land surface temperature (LST) within 1°C. Evapotranspiration due to waterlogging in the northern regions of Belarus decreases and it increases in the southern regions, which is associated with a significant ratio between evaporation and transpiration in these regions. During the afforestation of cropland, the daytime LST of Belarus decreases within 2°C and, at night, increase. The total evapotranspiration for the growing season due to the increase in forest cover reaches 100 mm, and potential (maximum possible) evaporation remains at the same level, which contributes to an increase in soil moisture at an increased amount of atmospheric precipitation. The above changes in the physical characteristics of the land surface as a result of reclamation cause a decrease in the surface air temperature in the reclamated region within 0.4°C and an increase in the amount of atmospheric precipitation within 2% of the climatic normals. At the same time, the maximum in the spatial distribution of secondary precipitation due to western transport shifts to the east relative to the reclaimed region.
A
bstract
The cross section of the process
e
+
e
−
→
π
+
π
−
has been measured in the Spherical Neutral Detector (SND) experiment at the VEPP-2000
e
+
e
−
collider VEPP-2000 in the energy region 525
...<
s
<
883 MeV. The measurement is based on data with an integrated luminosity of about 4.6 pb
−
1
. The systematic uncertainty of the cross section determination is 0.8% at
s
>
0
.
600 GeV. The
ρ
meson parameters are obtained as
m
ρ
= 775
.
3 ± 0
.
5 ± 0
.
6 MeV, Γ
ρ
= 145
.
6 ± 0
.
6 ± 0
.
8 MeV,
B
ρ
→
e
+
e−
×
B
ρ
→
π
+
π−
= (4
.
89 ± 0
.
02 ± 0
.
04) × 10
−
5
, and the parameters of the
e
+
e
−
→
ω
→
π
+
π
−
process, suppressed by
G
-parity, as
B
ω
→
e
+
e−
×
B
ω
→
π
+
π−
= (1
.
32 ± 0
.
06 ± 0
.
02) × 10
−
6
and and
ϕ
ρω
= 110
.
7 ± 1
.
5 ± 1
.
0 degrees.
Abstract
Myelofibrosis is a hematopoietic stem cell disorder belonging to the myeloproliferative neoplasms. Myelofibrosis patients frequently carry driver mutations in either
JAK2
or Calreticulin (
...CALR
) and have limited therapeutic options. Here, we integrate ex vivo drug response and proteotype analyses across myelofibrosis patient cohorts to discover targetable vulnerabilities and associated therapeutic strategies. Drug sensitivities of mutated and progenitor cells were measured in patient blood using high-content imaging and single-cell deep learning-based analyses. Integration with matched molecular profiling revealed three targetable vulnerabilities. First,
CALR
mutations drive BET and HDAC inhibitor sensitivity, particularly in the absence of high Ras pathway protein levels. Second, an MCM complex-high proliferative signature corresponds to advanced disease and sensitivity to drugs targeting pro-survival signaling and DNA replication. Third, homozygous
CALR
mutations result in high endoplasmic reticulum (ER) stress, responding to ER stressors and unfolded protein response inhibition. Overall, our integrated analyses provide a molecularly motivated roadmap for individualized myelofibrosis patient treatment.
The influence of the degree of dispersion of a nickel–zinc ferrite powder of a Ni
0.7
Zn
0.3
Fe
2
O
4
composition on its magnetic properties has been considered. The material has been synthesized ...using the ceramic technology with preliminary mechanical activation of precursors. The degree of dispersion has been varied using different modes of its dry grinding in a ball mill. The patterns of the changes in saturation magnetization and the coercive force as a function of grinding modes and a specific surface area of the ferrite powder have been established. The changes in the pattern of the magnetic phase transition in the region of the Curie temperature of materials with different degrees of dispersion have been determined.
The paper studies magnetization of Li
0.4
Fe
2.4
Zn
0.2
O
4
lithium-zinc ferrite sintered by electron beam heating of a mechanically activated mixture of initial Fe
2
O
3
–Li
2
CO
3
–ZnO reagents ...based on measurements of the specific saturation magnetization and Curie point. Initial reagents are mechanically activated in a planetary ball mill for different time at 1290 and 2220 rpm grinding rate. Specimens are heated by using the pulse accelerator ILU-6 at the electron energy of 2.4 MeV. The synthesis temperature is 600 and 750°C at the exposure time not over 120 minutes. It is shown that preliminary grinding at 2220 rpm and successive electron beam heating at 750°C for 120 minutes, lead to the formation of the main ferrite concentration with the chemical formula specified during the reagent mixing. This is confirmed by the data on the specific saturation magnetization of 80 emu/g and the nominal value of the Curie point of 500°C. This mode allows to significantly reduce the ferrite synthesis temperature compared to the traditional ceramic technology.
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