This paper concerns main results of research on interacting process of blade and ice during mechanical corrosion. It describes experimental research conditions and their main results. The paper shows ...argument of reasonable geometrical parameters of blades providing minimal storage density value of tested process.
The article discusses the possibility of increasing the efficiency of the working attachments of road machines and their adaptation to work in various conditions, due to the group equipping with ...single saw blades placed according to specially developed schemes. The main results of studies of the processes of interaction of a saw blade moving in space with a variable speed with ice during its mechanical destruction are presented. The conditions for conducting experimental studies, the composition and general structure of the main and auxiliary laboratory equipment used are described. The main results of laboratory research are stated. Taking these results into account, the specific energy intensity of the process under study was calculated, the graphs of the dependence of the specified parameter on the cutting speed were plotted, and conclusions were formulated on the work. The substantiation of rational operating parameters of saw blades is given, which ensure the minimum specific energy consumption of the process under study.
The MuCap experiment at the Paul Scherrer Institute has measured the rate Λ(S) of muon capture from the singlet state of the muonic hydrogen atom to a precision of 1%. A muon beam was stopped in a ...time projection chamber filled with 10-bar, ultrapure hydrogen gas. Cylindrical wire chambers and a segmented scintillator barrel detected electrons from muon decay. Λ(S) is determined from the difference between the μ(-) disappearance rate in hydrogen and the free muon decay rate. The result is based on the analysis of 1.2 × 10(10) μ(-) decays, from which we extract the capture rate Λ(S) = (714.9 ± 5.4(stat) ± 5.1(syst)) s(-1) and derive the proton's pseudoscalar coupling g(P)(q(0)(2) = -0.88 m(μ)(2)) = 8.06 ± 0.55.
Purpose
The role of genetic polymorphisms in the pathogenesis of recurrent pregnancy loss (RPL) has been studied intensively. Complex diseases, including miscarriage, are believed to have a polygenic ...basis, and gene–gene interactions can play a significant role in the etiology of the disease. This study was conducted to investigate the association of gene–gene interactions with angiogenesis, endothelial dysfunction-related gene polymorphisms, and RPL.
Methods
A case–control study was conducted with 253 unrelated RPL patients with 2 or more spontaneous pregnancy losses and 339 healthy women with no history of pregnancy complications. Genotyping of single-nucleotide polymorphisms (SNPs) was performed using real-time polymerase chain reaction (real-time PCR), restriction fragment length polymorphism (RFLP), or allele-specific polymerase chain reaction methods.
Results
The genotypes 677TT of the
MTHFR
gene, 936TT, 936CT, and 634CC, 634GC of the
VEGF
gene, and allele 894T of the
NOS3
gene were associated with a predisposition to RPL in the Russian population. A significant role of additive and epistatic effects in the gene–gene interactions of the SNPs of
SERPINE-1
,
ACE
,
NOS3
,
MTHFR
, and
VEGF
genes in RPL was demonstrated.
Conclusions
The results showed that gene–gene interactions are important for RPL susceptibility. Additionally, analysis of the genotype combinations of several allelic variants provides more information on RPL risk than analysis of independent polymorphic markers.
The present study considers an environmental analysis of gasoline and diesel fuel use in Russia. Volume dynamics of atmospheric pollutant emission from stationary and mobile sources is presented. ...Chemical composition of vehicle exhaust gases is examined and toxicity of components is estimated as well as their adverse health effects in exposed people. The changes in the concentrations of detected substances in recent years are analyzed. Prospects for the use of NGV (natural gas vehicle) fuels are defined. Comparative characterization of toxic substances emissions into the environment when using natural gas instead of petroleum fuel is provided.
The rate of nuclear muon capture by the proton has been measured using a new technique based on a time projection chamber operating in ultraclean, deuterium-depleted hydrogen gas, which is key to ...avoiding uncertainties from muonic molecule formation. The capture rate from the hyperfine singlet ground state of the microp atom was obtained from the difference between the micro(-) disappearance rate in hydrogen and the world average for the micro(+) decay rate, yielding Lambda(S)=725.0+/-17.4 s(-1), from which the induced pseudoscalar coupling of the nucleon, g(P)(q(2)=-0.88m(2)(micro))=7.3+/-1.1, is extracted.
The paper presents the geological setting, structure, lithology, and placer-controlling factors in the Krasnokutsk placer rare metal–titanium deposit located in Miocene sediments on the northeastern ...slope of the Dnieper-Donets Depression. The identified lithofacies (alluvial-deltaic, coastal- and shallow-marine, eolian) complexes correspond to the lower (Aquitanian), middle (Burdigalian), and upper (Langian) subformations of the Miocene Novopetrovsk Formation. Placer bodies are confined to the littoral coastal-marine complexes of the middle Novopetrovsk subformation. Placer formation is related to coastline stabilization phases at the regressive stage of the Sub-Paratethys Basin existence. The main prospecting criteria for the identification of promising sectors in the Kharkov–Sumy placer zone are: coastline stabilization areas of the regressive stage of the middle Novopetrovsk basin evolution and development of transverse alluvial-deltaic structures that delivered into the basin low-metalliferous sediments, which distorted the monotonous pattern of alongshore transport and played the role of structural-sedimentational traps. The developed digital lithostructural model of the Krasnokutsk deposit makes it possible to propose a criterion complex for a comparative assessment of different sectors of the deposit to define the priority order of their development. The mineral composition of productive rocks is typical of placers for the study region and rare metal–titanium placers in general. Increased rutile and zircon contents, which augment the industrial value of placers in this zone, are related to the influence of crystalline rocks of the Voronezh Massif.
Search for Muon Catalyzed 3Hed Fusion Fotev, V. D.; Ganzha, V. A.; Ivshin, K. A. ...
Physics of particles and nuclei,
06/2024, Letnik:
55, Številka:
3
Journal Article
Recenzirano
—This report presents the results of an experiment aimed at observation of the muon catalyzed
3
He
d
fusion reaction
3
He +
(3.66 MeV) +
p
(14.64 MeV) + μ which might occur after a negative muon stop ...in the D
2
+
3
He gas mixture. The basic element of the experimental setup is a Time Projection Chamber (TPC) which can detect the incoming muons and the products of the fusion reaction. The TPC operated with the D
2
+
3
He (5%) gas mixture at 31 K temperature. About
3
Heμ
d
molecules were produced with only 2 registered candidates for the muon catalyzed
3
He
d
fusion with the expected background
events. This gives an upper limit for the probability of the fusion decay of the
3
Heμ
d
molecule
at 90% C.L. Also presented are the measured formation rate of the
3
Heμ
d
molecule
and the probability of the fast muon transfer from the excited to the ground state of the
atom
. The obtained results are compared with the previously published data.
The paper analyzes the structural features of perovskite-like ABO3 type materials responsible for the formation of antiferroelectric phases. For this purpose, the descriptions of some single crystals ...have been compared using three models: the adapted Slater dipole model (I), the Cowley shell model (II) and the Born – Karman model supplemented with consideration dipole-dipole forces and parameterized basing on ab initio calculations by Ghosez (III). The parameters of model I were found at which qualitative agreement with the data on inelastic X-ray scattering obtained by experiments with lead hafnate was observed. An analysis of all the results led to the conclusion that model I and the Ghosez parameterization confirmed the hypothesis about the key role of the lateral component of the oxygen atoms’ polarizability over its axial component for the antiferroelectricity formation. However, model II data did not support this.
Muon catalyzed
dd
fusion in D
2
and HD gases in the temperature range from 28 to 350 K was investigated in a series of experiments based on a time-projection ionization chamber operating with pure ...hydrogen. All main observables in this reaction chain were measured with high absolute precision including the resonant and non-resonant
dd
μ formation rates, the rate for hyperfine transitions in
d
μ atoms, the branching ratio of the two charge symmetric fusion channels
3
He +
n
and
t
+
p
and the muon sticking probability. The report presents the final analysis of the data together with a comprehensive comparison with calculations based on recent μCF theories. The energy of the loosely bound
dd
μ state with quantum numbers
J
= 1,
ν
= 1, which is central to the mechanism of resonant molecule formation, is extracted with precision ɛ
11
(fit) = −1.9651(7) eV. in impressive agreement with the latest theoretical results ɛ
11
(theory) = −1.9646 eV.
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