Study of fluctuations in secondary particles distributions in interactions of nuclei of different energies and asymmetry degree

According to the present-day conceptions, the hadron substance transits within the interactions of the nuclei, at the high energies, into a state of the quark-gluon plasma (QGP), in which the quarks and gluons stay in a quasi-free state; that is, the process of deconfinement is observed [1]. Experimentally, a deconfinement process (a process of transition of the hadronic matter into a state of the quark-gluon plasma) may be registered by analysis of the essential fluctuations within the distributions of the secondary particles..

Sensitivity to vapors of ethanol of thin films of SnO2 alloyed by fluorine after isothermal annealing

Films of tin oxide are intensively used as a sensitive element of sensors for the determination of various gases in atmospheric air [1]. The principle of operation of these sensors is based on the modulation of the near-surface space charge region and the change in the electrical resistivity of film crystals upon adsorption of gas molecules. In order for physicochemical processes to proceed quickly on the surface of the sensitive layer, providing a response time of several seconds, the sensor is heated to a temperature of 100-450 ° C, which "activates" its surface. Sensors are used by environmental services, chemical enterprises, in oil and gas industry - wherever it is necessary to make express measurements of the concentrations of such gases as: propane, methane, hydrogen, vapors of ethyl alcohol. For a long time, thin films are in a state heated to 400°C. Determining how long the film can retain its useful properties in the operating mode is an actual scientific and practical task

Influence of plasma exposure on physical characteristics of thin films of SnO2 obtained from SnCl4 solutions with additives of NH4F and NH4OH

The electrical conductivity of tin dioxide is extremely sensitive to the state of the surface in the temperature range 300-800 K, at which oxidation-reduction reactions take place on its surface. Nanocrystalline films of tin dioxide are selectively sensitive to the presence of toxic gases, organic and certain biological molecules in the surrounding atmosphere [1]. SnO2-based films are also used as transparent conductive coatings [2]. To modify the properties of the films, alloying, heat treatment, plasma treatment is used

Initial State Fluctuations and Complete Destruction of the Projectile Nucleus in Interactions of Asymmetric Nuclei at High Energies

A study of characteristics of the events of complete destruction of the projectile nucleus in the interactions between asymmetric nuclei for different initial states of the collision, is performed. In the interactions of the sulfur nuclei with heavy emulsion nuclei at energy 200 AGeV, anomalous high number of events the complete destruction of the projectile nuclei, is observed. The high probability of such events depends on the energy of interaction (it is not detected in the interactions of the sulfur nuclei with emulsion nuclei at energy of 3.7 AGeV), on the degree of asymmetry of the interacting nuclei (it is not detected in interactions of the sulfur nuclei with light emulsion nuclei) and on initial state of interaction (it is not detected in peripheral collisions). These events are characterized by high multiplicity of secondary particles and narrow angular distribution at large angles (they form narrow peak in the region of small values of average pseudorapidity)

Influence of plasma exposure on physical characteristics of thin films of SnO2 obtained from SnCl4 solutions with additives of NH4F and NH4OH

The electrical conductivity of tin dioxide is extremely sensitive to the state of the surface in the temperature range 300-800 K, at which oxidation-reduction reactions take place on its surface. Nanocrystalline films of tin dioxide are selectively sensitive to the presence of toxic gases, organic and certain biological molecules in the surrounding atmosphere [1]. SnO2-based films are also used as transparent conductive coatings [2]. To modify the properties of the films, alloying, heat treatment, plasma treatment is used

Analysis of Midrapidity <inline-formula><math display="inline"><semantics><mrow><msub><mi mathvariant="bold-italic">p</mi><mi mathvariant="bold-italic">T</mi></msub></mrow></semantics></math></inline-formula> Distributions of Identified Charged Particles in Pb + Pb Collisions at <inline-formula><math display="inline"><semantics><mrow><msqrt><mrow><msub><mi mathvariant="bold-italic">s</mi><mrow><mi mathvariant="bold-italic">n</mi><mi mathvariant="bold-italic">n</mi></mrow></msub></mrow></msqrt></mrow></semantics></math></inline-formula> = 5.02 TeV Using Tsallis Distribution with Embedded Transverse Flow

The midrapidity transverse momentum distributions of the charged pions, kaons, protons, and antiprotons, measured by ALICE Collaboration at ten centrality classes of Pb + Pb collisions at snn  = 5.02 TeV in the Large Hadron Collider (LHC, CERN, Switzerland), are successfully analyzed using combined minimum χ2 fits with a thermodynamically non-consistent, as well as thermodynamically consistent, Tsallis function with transverse flow. The extracted non-extensivity parameter q decreases systematically for all considered particle species with increasing Pb + Pb collision centrality, suggesting an increase in the degree of system thermalization with an increase in collision centrality. The results for q suggest quite a large degree of thermalization of quark–gluon plasma (QGP) created in central Pb + Pb collisions at snn = 5.02 TeV with the average number of participant nucleons ⟨Npart⟩ > 160. The obtained significantly different growth rates of transverse flow velocity, ⟨βT⟩, in regions ⟨Npart⟩ ⟨Npart⟩ > 71 ± 7 with the temperature parameter T0 remaining constant within uncertainties in region ⟨Npart⟩ > 71 ± 7 probably indicates that ⟨Npart⟩ ≈ 71 ± 7 (corresponding to ⟨dNch/dη⟩ ≈ 251 ± 20) is a threshold border value for a crossover transition from a dense hadronic state to the QGP phase (or mixed phase of QGP and hadrons) in Pb + Pb collisions at snn = 5.02 TeV. The threshold border value for transverse flow velocity ⟨βT⟩ ≈ 0.46 ± 0.03 (corresponding to ⟨Npart⟩ ≈ 71 ± 7), estimated by us in Pb + Pb collisions at snn = 5.02 TeV, agrees well with the corresponding border value ⟨βT⟩ ≈ 0.44 ± 0.02, recently obtained in Xe + Xe collisions at snn = 5.44 TeV, and with almost constant ⟨βT⟩ values extracted earlier in the Beam Energy Scan (BES) program of the Relativistic Heavy-Ion Collider (RHIC, Brookhaven, GA, USA) in central Au + Au collisions in the snn = 7.7 − 39 GeV energy range, where the threshold for QGP production is achieved. The correlations between extracted T0 and ⟨βT⟩ parameters are found to be greatly different in regions ⟨βT⟩ ⟨βT⟩ > 0.46, which further supports our result obtained for the threshold border value in Pb + Pb collisions at snn = 5.02 TeV

THE EFFECT OF DEPOSITION TECHNIQUE ON FORMATION OF TRANSPARENT CONDUCTIVE COATINGS OF SnO2

The producing technology of transparent conductive layers is the basis for many optoelectronic devices. To increase transparency and conductivity at low-cost and controlled methods is an important challenge. Studied samples of SnO2 coatings were obtained by sol-gel method. The deposition of films on glass substrates was carried out by dip coating, spin-coating and sprays-pyrolysis methods. According to micro-weighing, the film thickness varies from 250 nm to 290 nm. The layer with the most uniform thickness was achieved using spray pyrolysis. Films deposited by this technique exhibit the greatest transparency and lowest resistance. It is important to note that these samples have the minimum scatter of resistance values depending on the surface area. In case dip coating technique the resultant film contains open- and closed-type blisters. This confirms the fact of inhomogeneous surface morphology of these films. X-ray diffraction analysis showed that films obtained by spin-coating and dipping methods contain SnO2 crystallites, the size of which does not exceed 10.3 nm; while films obtained by spay pyrolysis are amorphous. This is because the formation of the structure in the spay pyrolysis proceeds faster due to the substrate heating

Simultaneous Analysis of Midrapidity&nbsp;pT Spectra of Identified Particle Species in Pb + Pb Collisions at snn = 2.76 TeV Using Tsallis Distribution with Transverse Flow

The midrapidity transverse momentum distributions of the charged pions, kaons, protons, and antiprotons in ten groups of centrality of Pb + Pb collisions at snn = 2.76 TeV, measured by the ALICE Collaboration, have been analyzed successfully using both thermodynamically consistent and non-consistent Tsallis distribution functions with transverse flow. The collision centrality dependencies of the extracted parameters of two kinds of Tsallis functions with transverse flow have been investigated. The significantly different behavior (growth rates) of &#10216;&beta;T&#10217; in regions &#10216;Npart&#10217; &lt; 71 and &#10216;Npart&#10217; &gt; 71 with the temperature T0 becoming constant in region &#10216;Npart&#10217; &gt; 71 has been observed. This could indicate that &#10216;Npart&#10217; = 71 &plusmn; 5 (corresponding to &#10216;dNch/d&eta;&#10217; = 205 &plusmn; 15) is a threshold border value of collision centrality for crossover phase transition from the dense hadronic state to the QGP state (or a mixed state of QGP and hadrons) in Pb + Pb collisions at snn = 2.76 TeV. This conjecture is supported further by the observed, significantly different correlations between T0 and &#10216;&beta;T&#10217; parameters in the corresponding &#10216;&beta;T&#10217; &lt; 0.44 and &#10216;&beta;T&#10217; &gt; 0.44 ranges. The strong positive linear correlation between non-extensivity parameter q for pions and kaons, between q for pions and (anti)protons, and between q for kaons and (anti)protons has been obtained. The parameter q for all studied particle species has proven to be strongly anticorrelated with the average transverse flow velocity, &#10216;&beta;T&#10217;. Quite a large positive linear correlation has been obtained between the q of the studied particle species and temperature parameter T0. Analysis of q versus &#10216;Npart&#10217; dependencies for the studied particle species suggests that the highly thermalized and equilibrated QGP is produced in central Pb + Pb collisions at snn = 2.76 TeV with &#10216;Npart&#10217; &gt; 160

Tailoring of silica nanoarchitecture to optimize Cu<inf>(2−x)</inf>S based image-guided chemodynamic therapy agent

The present work introduces various synthetic and post-synthetic modes of co-doping of oleate-oleylamine-stabilized Cu(2−x)S cores with red emitting [Ru(dipy)3]2+ into amino-modified silica nanoparticles (SNs) with the aim to combine chemodynamic therapy (CDT) with cellular uptake and imaging functions. Thereto, the ROS generation by the Cu(2−x)S embedded into the SNs was manifested by the spin trap facilitated ESR technique and correlated with such parameters as size of the embedded cores, content and oxidation extent of copper ions. The parameters were varied through the different extent of an oxidative degradation of the embedded Cu(2−x)S cores by their post-treating with histidine, polyethylenimine and citrate-stabilized carbon dots (CDs). The treating by CDs was chosen as the optimal post-synthetic modification of the composite SNs due to combination of CDT with high stability to aggregation. The green or dual green-red emission of the CD-treated composite SNs visualizes their cell internalization and intracellular localization by means of fluorescence and confocal microscopy methods. Correlation of cytotoxicity data of the differently treated composite SNs with their ability to ROS generation and the intracellular localization highlight the enhanced cell internalization and nuclear confinement of the CD-treated composite SNs as the factor enhancing their cytotoxicity in greater extent than the CDT function